1 //===-- AMDGPUISelLowering.cpp - AMDGPU Common DAG lowering functions -----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file
10 /// This is the parent TargetLowering class for hardware code gen
11 /// targets.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "AMDGPUISelLowering.h"
16 #include "AMDGPU.h"
17 #include "AMDGPUCallLowering.h"
18 #include "AMDGPUFrameLowering.h"
19 #include "AMDGPUSubtarget.h"
20 #include "AMDGPUTargetMachine.h"
21 #include "Utils/AMDGPUBaseInfo.h"
22 #include "R600MachineFunctionInfo.h"
23 #include "SIInstrInfo.h"
24 #include "SIMachineFunctionInfo.h"
25 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
26 #include "llvm/CodeGen/Analysis.h"
27 #include "llvm/CodeGen/CallingConvLower.h"
28 #include "llvm/CodeGen/MachineFunction.h"
29 #include "llvm/CodeGen/MachineRegisterInfo.h"
30 #include "llvm/CodeGen/SelectionDAG.h"
31 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/DiagnosticInfo.h"
34 #include "llvm/Support/KnownBits.h"
35 #include "llvm/Support/MathExtras.h"
36 using namespace llvm;
37 
38 #include "AMDGPUGenCallingConv.inc"
39 
40 static cl::opt<bool> AMDGPUBypassSlowDiv(
41   "amdgpu-bypass-slow-div",
42   cl::desc("Skip 64-bit divide for dynamic 32-bit values"),
43   cl::init(true));
44 
45 // Find a larger type to do a load / store of a vector with.
46 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
47   unsigned StoreSize = VT.getStoreSizeInBits();
48   if (StoreSize <= 32)
49     return EVT::getIntegerVT(Ctx, StoreSize);
50 
51   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
52   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
53 }
54 
55 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
56   EVT VT = Op.getValueType();
57   KnownBits Known = DAG.computeKnownBits(Op);
58   return VT.getSizeInBits() - Known.countMinLeadingZeros();
59 }
60 
61 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
62   EVT VT = Op.getValueType();
63 
64   // In order for this to be a signed 24-bit value, bit 23, must
65   // be a sign bit.
66   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
67 }
68 
69 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
70                                            const AMDGPUSubtarget &STI)
71     : TargetLowering(TM), Subtarget(&STI) {
72   // Lower floating point store/load to integer store/load to reduce the number
73   // of patterns in tablegen.
74   setOperationAction(ISD::LOAD, MVT::f32, Promote);
75   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
76 
77   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
78   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
79 
80   setOperationAction(ISD::LOAD, MVT::v3f32, Promote);
81   AddPromotedToType(ISD::LOAD, MVT::v3f32, MVT::v3i32);
82 
83   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
84   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
85 
86   setOperationAction(ISD::LOAD, MVT::v5f32, Promote);
87   AddPromotedToType(ISD::LOAD, MVT::v5f32, MVT::v5i32);
88 
89   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
90   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
91 
92   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
93   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
94 
95   setOperationAction(ISD::LOAD, MVT::v32f32, Promote);
96   AddPromotedToType(ISD::LOAD, MVT::v32f32, MVT::v32i32);
97 
98   setOperationAction(ISD::LOAD, MVT::i64, Promote);
99   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
100 
101   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
102   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
103 
104   setOperationAction(ISD::LOAD, MVT::f64, Promote);
105   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
106 
107   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
108   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
109 
110   setOperationAction(ISD::LOAD, MVT::v4i64, Promote);
111   AddPromotedToType(ISD::LOAD, MVT::v4i64, MVT::v8i32);
112 
113   setOperationAction(ISD::LOAD, MVT::v4f64, Promote);
114   AddPromotedToType(ISD::LOAD, MVT::v4f64, MVT::v8i32);
115 
116   setOperationAction(ISD::LOAD, MVT::v8i64, Promote);
117   AddPromotedToType(ISD::LOAD, MVT::v8i64, MVT::v16i32);
118 
119   setOperationAction(ISD::LOAD, MVT::v8f64, Promote);
120   AddPromotedToType(ISD::LOAD, MVT::v8f64, MVT::v16i32);
121 
122   setOperationAction(ISD::LOAD, MVT::v16i64, Promote);
123   AddPromotedToType(ISD::LOAD, MVT::v16i64, MVT::v32i32);
124 
125   setOperationAction(ISD::LOAD, MVT::v16f64, Promote);
126   AddPromotedToType(ISD::LOAD, MVT::v16f64, MVT::v32i32);
127 
128   // There are no 64-bit extloads. These should be done as a 32-bit extload and
129   // an extension to 64-bit.
130   for (MVT VT : MVT::integer_valuetypes()) {
131     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
132     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
133     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
134   }
135 
136   for (MVT VT : MVT::integer_valuetypes()) {
137     if (VT == MVT::i64)
138       continue;
139 
140     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
141     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
142     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
143     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
144 
145     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
146     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
147     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
148     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
149 
150     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
151     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
152     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
153     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
154   }
155 
156   for (MVT VT : MVT::integer_fixedlen_vector_valuetypes()) {
157     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
158     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
159     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
160     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
161     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
162     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
163     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
164     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
165     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
166     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v3i16, Expand);
167     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v3i16, Expand);
168     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v3i16, Expand);
169     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
170     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
171     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
172   }
173 
174   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
175   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
176   setLoadExtAction(ISD::EXTLOAD, MVT::v3f32, MVT::v3f16, Expand);
177   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
178   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
179   setLoadExtAction(ISD::EXTLOAD, MVT::v16f32, MVT::v16f16, Expand);
180   setLoadExtAction(ISD::EXTLOAD, MVT::v32f32, MVT::v32f16, Expand);
181 
182   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
183   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
184   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
185   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
186   setLoadExtAction(ISD::EXTLOAD, MVT::v16f64, MVT::v16f32, Expand);
187 
188   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
189   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
190   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
191   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
192   setLoadExtAction(ISD::EXTLOAD, MVT::v16f64, MVT::v16f16, Expand);
193 
194   setOperationAction(ISD::STORE, MVT::f32, Promote);
195   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
196 
197   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
198   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
199 
200   setOperationAction(ISD::STORE, MVT::v3f32, Promote);
201   AddPromotedToType(ISD::STORE, MVT::v3f32, MVT::v3i32);
202 
203   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
204   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
205 
206   setOperationAction(ISD::STORE, MVT::v5f32, Promote);
207   AddPromotedToType(ISD::STORE, MVT::v5f32, MVT::v5i32);
208 
209   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
210   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
211 
212   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
213   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
214 
215   setOperationAction(ISD::STORE, MVT::v32f32, Promote);
216   AddPromotedToType(ISD::STORE, MVT::v32f32, MVT::v32i32);
217 
218   setOperationAction(ISD::STORE, MVT::i64, Promote);
219   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
220 
221   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
222   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
223 
224   setOperationAction(ISD::STORE, MVT::f64, Promote);
225   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
226 
227   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
228   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
229 
230   setOperationAction(ISD::STORE, MVT::v4i64, Promote);
231   AddPromotedToType(ISD::STORE, MVT::v4i64, MVT::v8i32);
232 
233   setOperationAction(ISD::STORE, MVT::v4f64, Promote);
234   AddPromotedToType(ISD::STORE, MVT::v4f64, MVT::v8i32);
235 
236   setOperationAction(ISD::STORE, MVT::v8i64, Promote);
237   AddPromotedToType(ISD::STORE, MVT::v8i64, MVT::v16i32);
238 
239   setOperationAction(ISD::STORE, MVT::v8f64, Promote);
240   AddPromotedToType(ISD::STORE, MVT::v8f64, MVT::v16i32);
241 
242   setOperationAction(ISD::STORE, MVT::v16i64, Promote);
243   AddPromotedToType(ISD::STORE, MVT::v16i64, MVT::v32i32);
244 
245   setOperationAction(ISD::STORE, MVT::v16f64, Promote);
246   AddPromotedToType(ISD::STORE, MVT::v16f64, MVT::v32i32);
247 
248   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
249   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
250   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
251   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
252 
253   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
254   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
255   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
256   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
257 
258   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
259   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
260   setTruncStoreAction(MVT::v3f32, MVT::v3f16, Expand);
261   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
262   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
263   setTruncStoreAction(MVT::v16f32, MVT::v16f16, Expand);
264   setTruncStoreAction(MVT::v32f32, MVT::v32f16, Expand);
265 
266   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
267   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
268 
269   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
270   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
271 
272   setTruncStoreAction(MVT::v4i64, MVT::v4i32, Expand);
273   setTruncStoreAction(MVT::v4i64, MVT::v4i16, Expand);
274   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
275   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
276 
277   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
278   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
279 
280   setTruncStoreAction(MVT::v16f64, MVT::v16f32, Expand);
281   setTruncStoreAction(MVT::v16f64, MVT::v16f16, Expand);
282   setTruncStoreAction(MVT::v16i64, MVT::v16i16, Expand);
283   setTruncStoreAction(MVT::v16i64, MVT::v16i16, Expand);
284   setTruncStoreAction(MVT::v16i64, MVT::v16i8, Expand);
285   setTruncStoreAction(MVT::v16i64, MVT::v16i8, Expand);
286   setTruncStoreAction(MVT::v16i64, MVT::v16i1, Expand);
287 
288   setOperationAction(ISD::Constant, MVT::i32, Legal);
289   setOperationAction(ISD::Constant, MVT::i64, Legal);
290   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
291   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
292 
293   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
294   setOperationAction(ISD::BRIND, MVT::Other, Expand);
295 
296   // This is totally unsupported, just custom lower to produce an error.
297   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
298 
299   // Library functions.  These default to Expand, but we have instructions
300   // for them.
301   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
302   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
303   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
304   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
305   setOperationAction(ISD::FABS,   MVT::f32, Legal);
306   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
307   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
308   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
309   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
310   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
311 
312   setOperationAction(ISD::FROUND, MVT::f32, Custom);
313   setOperationAction(ISD::FROUND, MVT::f64, Custom);
314 
315   setOperationAction(ISD::FLOG, MVT::f32, Custom);
316   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
317   setOperationAction(ISD::FEXP, MVT::f32, Custom);
318 
319 
320   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
321   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
322 
323   setOperationAction(ISD::FREM, MVT::f32, Custom);
324   setOperationAction(ISD::FREM, MVT::f64, Custom);
325 
326   // Expand to fneg + fadd.
327   setOperationAction(ISD::FSUB, MVT::f64, Expand);
328 
329   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3i32, Custom);
330   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3f32, Custom);
331   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
332   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
333   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5i32, Custom);
334   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5f32, Custom);
335   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
336   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
337   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
338   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
339   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3f32, Custom);
340   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3i32, Custom);
341   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
342   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
343   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5f32, Custom);
344   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5i32, Custom);
345   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
346   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
347   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16f32, Custom);
348   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16i32, Custom);
349   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32f32, Custom);
350   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32i32, Custom);
351   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f64, Custom);
352   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i64, Custom);
353   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f64, Custom);
354   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i64, Custom);
355   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f64, Custom);
356   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i64, Custom);
357   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16f64, Custom);
358   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16i64, Custom);
359 
360   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
361   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
362   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
363 
364   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
365   for (MVT VT : ScalarIntVTs) {
366     // These should use [SU]DIVREM, so set them to expand
367     setOperationAction(ISD::SDIV, VT, Expand);
368     setOperationAction(ISD::UDIV, VT, Expand);
369     setOperationAction(ISD::SREM, VT, Expand);
370     setOperationAction(ISD::UREM, VT, Expand);
371 
372     // GPU does not have divrem function for signed or unsigned.
373     setOperationAction(ISD::SDIVREM, VT, Custom);
374     setOperationAction(ISD::UDIVREM, VT, Custom);
375 
376     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
377     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
378     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
379 
380     setOperationAction(ISD::BSWAP, VT, Expand);
381     setOperationAction(ISD::CTTZ, VT, Expand);
382     setOperationAction(ISD::CTLZ, VT, Expand);
383 
384     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
385     setOperationAction(ISD::ADDC, VT, Legal);
386     setOperationAction(ISD::SUBC, VT, Legal);
387     setOperationAction(ISD::ADDE, VT, Legal);
388     setOperationAction(ISD::SUBE, VT, Legal);
389   }
390 
391   // The hardware supports 32-bit FSHR, but not FSHL.
392   setOperationAction(ISD::FSHR, MVT::i32, Legal);
393 
394   // The hardware supports 32-bit ROTR, but not ROTL.
395   setOperationAction(ISD::ROTL, MVT::i32, Expand);
396   setOperationAction(ISD::ROTL, MVT::i64, Expand);
397   setOperationAction(ISD::ROTR, MVT::i64, Expand);
398 
399   setOperationAction(ISD::MUL, MVT::i64, Expand);
400   setOperationAction(ISD::MULHU, MVT::i64, Expand);
401   setOperationAction(ISD::MULHS, MVT::i64, Expand);
402   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
403   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
404   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
405   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
406   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
407 
408   setOperationAction(ISD::SMIN, MVT::i32, Legal);
409   setOperationAction(ISD::UMIN, MVT::i32, Legal);
410   setOperationAction(ISD::SMAX, MVT::i32, Legal);
411   setOperationAction(ISD::UMAX, MVT::i32, Legal);
412 
413   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
414   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
415   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
416   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
417 
418   static const MVT::SimpleValueType VectorIntTypes[] = {
419     MVT::v2i32, MVT::v3i32, MVT::v4i32, MVT::v5i32
420   };
421 
422   for (MVT VT : VectorIntTypes) {
423     // Expand the following operations for the current type by default.
424     setOperationAction(ISD::ADD,  VT, Expand);
425     setOperationAction(ISD::AND,  VT, Expand);
426     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
427     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
428     setOperationAction(ISD::MUL,  VT, Expand);
429     setOperationAction(ISD::MULHU, VT, Expand);
430     setOperationAction(ISD::MULHS, VT, Expand);
431     setOperationAction(ISD::OR,   VT, Expand);
432     setOperationAction(ISD::SHL,  VT, Expand);
433     setOperationAction(ISD::SRA,  VT, Expand);
434     setOperationAction(ISD::SRL,  VT, Expand);
435     setOperationAction(ISD::ROTL, VT, Expand);
436     setOperationAction(ISD::ROTR, VT, Expand);
437     setOperationAction(ISD::SUB,  VT, Expand);
438     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
439     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
440     setOperationAction(ISD::SDIV, VT, Expand);
441     setOperationAction(ISD::UDIV, VT, Expand);
442     setOperationAction(ISD::SREM, VT, Expand);
443     setOperationAction(ISD::UREM, VT, Expand);
444     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
445     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
446     setOperationAction(ISD::SDIVREM, VT, Expand);
447     setOperationAction(ISD::UDIVREM, VT, Expand);
448     setOperationAction(ISD::SELECT, VT, Expand);
449     setOperationAction(ISD::VSELECT, VT, Expand);
450     setOperationAction(ISD::SELECT_CC, VT, Expand);
451     setOperationAction(ISD::XOR,  VT, Expand);
452     setOperationAction(ISD::BSWAP, VT, Expand);
453     setOperationAction(ISD::CTPOP, VT, Expand);
454     setOperationAction(ISD::CTTZ, VT, Expand);
455     setOperationAction(ISD::CTLZ, VT, Expand);
456     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
457     setOperationAction(ISD::SETCC, VT, Expand);
458   }
459 
460   static const MVT::SimpleValueType FloatVectorTypes[] = {
461      MVT::v2f32, MVT::v3f32, MVT::v4f32, MVT::v5f32
462   };
463 
464   for (MVT VT : FloatVectorTypes) {
465     setOperationAction(ISD::FABS, VT, Expand);
466     setOperationAction(ISD::FMINNUM, VT, Expand);
467     setOperationAction(ISD::FMAXNUM, VT, Expand);
468     setOperationAction(ISD::FADD, VT, Expand);
469     setOperationAction(ISD::FCEIL, VT, Expand);
470     setOperationAction(ISD::FCOS, VT, Expand);
471     setOperationAction(ISD::FDIV, VT, Expand);
472     setOperationAction(ISD::FEXP2, VT, Expand);
473     setOperationAction(ISD::FEXP, VT, Expand);
474     setOperationAction(ISD::FLOG2, VT, Expand);
475     setOperationAction(ISD::FREM, VT, Expand);
476     setOperationAction(ISD::FLOG, VT, Expand);
477     setOperationAction(ISD::FLOG10, VT, Expand);
478     setOperationAction(ISD::FPOW, VT, Expand);
479     setOperationAction(ISD::FFLOOR, VT, Expand);
480     setOperationAction(ISD::FTRUNC, VT, Expand);
481     setOperationAction(ISD::FMUL, VT, Expand);
482     setOperationAction(ISD::FMA, VT, Expand);
483     setOperationAction(ISD::FRINT, VT, Expand);
484     setOperationAction(ISD::FNEARBYINT, VT, Expand);
485     setOperationAction(ISD::FSQRT, VT, Expand);
486     setOperationAction(ISD::FSIN, VT, Expand);
487     setOperationAction(ISD::FSUB, VT, Expand);
488     setOperationAction(ISD::FNEG, VT, Expand);
489     setOperationAction(ISD::VSELECT, VT, Expand);
490     setOperationAction(ISD::SELECT_CC, VT, Expand);
491     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
492     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
493     setOperationAction(ISD::SETCC, VT, Expand);
494     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
495   }
496 
497   // This causes using an unrolled select operation rather than expansion with
498   // bit operations. This is in general better, but the alternative using BFI
499   // instructions may be better if the select sources are SGPRs.
500   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
501   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
502 
503   setOperationAction(ISD::SELECT, MVT::v3f32, Promote);
504   AddPromotedToType(ISD::SELECT, MVT::v3f32, MVT::v3i32);
505 
506   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
507   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
508 
509   setOperationAction(ISD::SELECT, MVT::v5f32, Promote);
510   AddPromotedToType(ISD::SELECT, MVT::v5f32, MVT::v5i32);
511 
512   // There are no libcalls of any kind.
513   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
514     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
515 
516   setSchedulingPreference(Sched::RegPressure);
517   setJumpIsExpensive(true);
518 
519   // FIXME: This is only partially true. If we have to do vector compares, any
520   // SGPR pair can be a condition register. If we have a uniform condition, we
521   // are better off doing SALU operations, where there is only one SCC. For now,
522   // we don't have a way of knowing during instruction selection if a condition
523   // will be uniform and we always use vector compares. Assume we are using
524   // vector compares until that is fixed.
525   setHasMultipleConditionRegisters(true);
526 
527   setMinCmpXchgSizeInBits(32);
528   setSupportsUnalignedAtomics(false);
529 
530   PredictableSelectIsExpensive = false;
531 
532   // We want to find all load dependencies for long chains of stores to enable
533   // merging into very wide vectors. The problem is with vectors with > 4
534   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
535   // vectors are a legal type, even though we have to split the loads
536   // usually. When we can more precisely specify load legality per address
537   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
538   // smarter so that they can figure out what to do in 2 iterations without all
539   // N > 4 stores on the same chain.
540   GatherAllAliasesMaxDepth = 16;
541 
542   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
543   // about these during lowering.
544   MaxStoresPerMemcpy  = 0xffffffff;
545   MaxStoresPerMemmove = 0xffffffff;
546   MaxStoresPerMemset  = 0xffffffff;
547 
548   // The expansion for 64-bit division is enormous.
549   if (AMDGPUBypassSlowDiv)
550     addBypassSlowDiv(64, 32);
551 
552   setTargetDAGCombine(ISD::BITCAST);
553   setTargetDAGCombine(ISD::SHL);
554   setTargetDAGCombine(ISD::SRA);
555   setTargetDAGCombine(ISD::SRL);
556   setTargetDAGCombine(ISD::TRUNCATE);
557   setTargetDAGCombine(ISD::MUL);
558   setTargetDAGCombine(ISD::MULHU);
559   setTargetDAGCombine(ISD::MULHS);
560   setTargetDAGCombine(ISD::SELECT);
561   setTargetDAGCombine(ISD::SELECT_CC);
562   setTargetDAGCombine(ISD::STORE);
563   setTargetDAGCombine(ISD::FADD);
564   setTargetDAGCombine(ISD::FSUB);
565   setTargetDAGCombine(ISD::FNEG);
566   setTargetDAGCombine(ISD::FABS);
567   setTargetDAGCombine(ISD::AssertZext);
568   setTargetDAGCombine(ISD::AssertSext);
569   setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
570 }
571 
572 //===----------------------------------------------------------------------===//
573 // Target Information
574 //===----------------------------------------------------------------------===//
575 
576 LLVM_READNONE
577 static bool fnegFoldsIntoOp(unsigned Opc) {
578   switch (Opc) {
579   case ISD::FADD:
580   case ISD::FSUB:
581   case ISD::FMUL:
582   case ISD::FMA:
583   case ISD::FMAD:
584   case ISD::FMINNUM:
585   case ISD::FMAXNUM:
586   case ISD::FMINNUM_IEEE:
587   case ISD::FMAXNUM_IEEE:
588   case ISD::FSIN:
589   case ISD::FTRUNC:
590   case ISD::FRINT:
591   case ISD::FNEARBYINT:
592   case ISD::FCANONICALIZE:
593   case AMDGPUISD::RCP:
594   case AMDGPUISD::RCP_LEGACY:
595   case AMDGPUISD::RCP_IFLAG:
596   case AMDGPUISD::SIN_HW:
597   case AMDGPUISD::FMUL_LEGACY:
598   case AMDGPUISD::FMIN_LEGACY:
599   case AMDGPUISD::FMAX_LEGACY:
600   case AMDGPUISD::FMED3:
601     return true;
602   default:
603     return false;
604   }
605 }
606 
607 /// \p returns true if the operation will definitely need to use a 64-bit
608 /// encoding, and thus will use a VOP3 encoding regardless of the source
609 /// modifiers.
610 LLVM_READONLY
611 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
612   return N->getNumOperands() > 2 || VT == MVT::f64;
613 }
614 
615 // Most FP instructions support source modifiers, but this could be refined
616 // slightly.
617 LLVM_READONLY
618 static bool hasSourceMods(const SDNode *N) {
619   if (isa<MemSDNode>(N))
620     return false;
621 
622   switch (N->getOpcode()) {
623   case ISD::CopyToReg:
624   case ISD::SELECT:
625   case ISD::FDIV:
626   case ISD::FREM:
627   case ISD::INLINEASM:
628   case ISD::INLINEASM_BR:
629   case AMDGPUISD::DIV_SCALE:
630   case ISD::INTRINSIC_W_CHAIN:
631 
632   // TODO: Should really be looking at the users of the bitcast. These are
633   // problematic because bitcasts are used to legalize all stores to integer
634   // types.
635   case ISD::BITCAST:
636     return false;
637   case ISD::INTRINSIC_WO_CHAIN: {
638     switch (cast<ConstantSDNode>(N->getOperand(0))->getZExtValue()) {
639     case Intrinsic::amdgcn_interp_p1:
640     case Intrinsic::amdgcn_interp_p2:
641     case Intrinsic::amdgcn_interp_mov:
642     case Intrinsic::amdgcn_interp_p1_f16:
643     case Intrinsic::amdgcn_interp_p2_f16:
644       return false;
645     default:
646       return true;
647     }
648   }
649   default:
650     return true;
651   }
652 }
653 
654 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
655                                                  unsigned CostThreshold) {
656   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
657   // it is truly free to use a source modifier in all cases. If there are
658   // multiple users but for each one will necessitate using VOP3, there will be
659   // a code size increase. Try to avoid increasing code size unless we know it
660   // will save on the instruction count.
661   unsigned NumMayIncreaseSize = 0;
662   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
663 
664   // XXX - Should this limit number of uses to check?
665   for (const SDNode *U : N->uses()) {
666     if (!hasSourceMods(U))
667       return false;
668 
669     if (!opMustUseVOP3Encoding(U, VT)) {
670       if (++NumMayIncreaseSize > CostThreshold)
671         return false;
672     }
673   }
674 
675   return true;
676 }
677 
678 EVT AMDGPUTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
679                                               ISD::NodeType ExtendKind) const {
680   assert(!VT.isVector() && "only scalar expected");
681 
682   // Round to the next multiple of 32-bits.
683   unsigned Size = VT.getSizeInBits();
684   if (Size <= 32)
685     return MVT::i32;
686   return EVT::getIntegerVT(Context, 32 * ((Size + 31) / 32));
687 }
688 
689 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
690   return MVT::i32;
691 }
692 
693 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
694   return true;
695 }
696 
697 // The backend supports 32 and 64 bit floating point immediates.
698 // FIXME: Why are we reporting vectors of FP immediates as legal?
699 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
700                                         bool ForCodeSize) const {
701   EVT ScalarVT = VT.getScalarType();
702   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
703          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
704 }
705 
706 // We don't want to shrink f64 / f32 constants.
707 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
708   EVT ScalarVT = VT.getScalarType();
709   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
710 }
711 
712 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
713                                                  ISD::LoadExtType ExtTy,
714                                                  EVT NewVT) const {
715   // TODO: This may be worth removing. Check regression tests for diffs.
716   if (!TargetLoweringBase::shouldReduceLoadWidth(N, ExtTy, NewVT))
717     return false;
718 
719   unsigned NewSize = NewVT.getStoreSizeInBits();
720 
721   // If we are reducing to a 32-bit load or a smaller multi-dword load,
722   // this is always better.
723   if (NewSize >= 32)
724     return true;
725 
726   EVT OldVT = N->getValueType(0);
727   unsigned OldSize = OldVT.getStoreSizeInBits();
728 
729   MemSDNode *MN = cast<MemSDNode>(N);
730   unsigned AS = MN->getAddressSpace();
731   // Do not shrink an aligned scalar load to sub-dword.
732   // Scalar engine cannot do sub-dword loads.
733   if (OldSize >= 32 && NewSize < 32 && MN->getAlignment() >= 4 &&
734       (AS == AMDGPUAS::CONSTANT_ADDRESS ||
735        AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT ||
736        (isa<LoadSDNode>(N) &&
737         AS == AMDGPUAS::GLOBAL_ADDRESS && MN->isInvariant())) &&
738       AMDGPUInstrInfo::isUniformMMO(MN->getMemOperand()))
739     return false;
740 
741   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
742   // extloads, so doing one requires using a buffer_load. In cases where we
743   // still couldn't use a scalar load, using the wider load shouldn't really
744   // hurt anything.
745 
746   // If the old size already had to be an extload, there's no harm in continuing
747   // to reduce the width.
748   return (OldSize < 32);
749 }
750 
751 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy, EVT CastTy,
752                                                    const SelectionDAG &DAG,
753                                                    const MachineMemOperand &MMO) const {
754 
755   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
756 
757   if (LoadTy.getScalarType() == MVT::i32)
758     return false;
759 
760   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
761   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
762 
763   if ((LScalarSize >= CastScalarSize) && (CastScalarSize < 32))
764     return false;
765 
766   bool Fast = false;
767   return allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
768                                         CastTy, MMO, &Fast) &&
769          Fast;
770 }
771 
772 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
773 // profitable with the expansion for 64-bit since it's generally good to
774 // speculate things.
775 // FIXME: These should really have the size as a parameter.
776 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
777   return true;
778 }
779 
780 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
781   return true;
782 }
783 
784 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
785   switch (N->getOpcode()) {
786     default:
787     return false;
788     case ISD::EntryToken:
789     case ISD::TokenFactor:
790       return true;
791     case ISD::INTRINSIC_WO_CHAIN:
792     {
793       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
794       switch (IntrID) {
795         default:
796         return false;
797         case Intrinsic::amdgcn_readfirstlane:
798         case Intrinsic::amdgcn_readlane:
799           return true;
800       }
801     }
802     break;
803     case ISD::LOAD:
804     {
805       if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
806           AMDGPUAS::CONSTANT_ADDRESS_32BIT)
807         return true;
808       return false;
809     }
810     break;
811   }
812 }
813 
814 SDValue AMDGPUTargetLowering::getNegatedExpression(
815     SDValue Op, SelectionDAG &DAG, bool LegalOperations, bool ForCodeSize,
816     NegatibleCost &Cost, unsigned Depth) const {
817 
818   switch (Op.getOpcode()) {
819   case ISD::FMA:
820   case ISD::FMAD: {
821     // Negating a fma is not free if it has users without source mods.
822     if (!allUsesHaveSourceMods(Op.getNode()))
823       return SDValue();
824     break;
825   }
826   default:
827     break;
828   }
829 
830   return TargetLowering::getNegatedExpression(Op, DAG, LegalOperations,
831                                               ForCodeSize, Cost, Depth);
832 }
833 
834 //===---------------------------------------------------------------------===//
835 // Target Properties
836 //===---------------------------------------------------------------------===//
837 
838 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
839   assert(VT.isFloatingPoint());
840 
841   // Packed operations do not have a fabs modifier.
842   return VT == MVT::f32 || VT == MVT::f64 ||
843          (Subtarget->has16BitInsts() && VT == MVT::f16);
844 }
845 
846 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
847   assert(VT.isFloatingPoint());
848   return VT == MVT::f32 || VT == MVT::f64 ||
849          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
850          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
851 }
852 
853 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
854                                                          unsigned NumElem,
855                                                          unsigned AS) const {
856   return true;
857 }
858 
859 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
860   // There are few operations which truly have vector input operands. Any vector
861   // operation is going to involve operations on each component, and a
862   // build_vector will be a copy per element, so it always makes sense to use a
863   // build_vector input in place of the extracted element to avoid a copy into a
864   // super register.
865   //
866   // We should probably only do this if all users are extracts only, but this
867   // should be the common case.
868   return true;
869 }
870 
871 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
872   // Truncate is just accessing a subregister.
873 
874   unsigned SrcSize = Source.getSizeInBits();
875   unsigned DestSize = Dest.getSizeInBits();
876 
877   return DestSize < SrcSize && DestSize % 32 == 0 ;
878 }
879 
880 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
881   // Truncate is just accessing a subregister.
882 
883   unsigned SrcSize = Source->getScalarSizeInBits();
884   unsigned DestSize = Dest->getScalarSizeInBits();
885 
886   if (DestSize== 16 && Subtarget->has16BitInsts())
887     return SrcSize >= 32;
888 
889   return DestSize < SrcSize && DestSize % 32 == 0;
890 }
891 
892 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
893   unsigned SrcSize = Src->getScalarSizeInBits();
894   unsigned DestSize = Dest->getScalarSizeInBits();
895 
896   if (SrcSize == 16 && Subtarget->has16BitInsts())
897     return DestSize >= 32;
898 
899   return SrcSize == 32 && DestSize == 64;
900 }
901 
902 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
903   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
904   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
905   // this will enable reducing 64-bit operations the 32-bit, which is always
906   // good.
907 
908   if (Src == MVT::i16)
909     return Dest == MVT::i32 ||Dest == MVT::i64 ;
910 
911   return Src == MVT::i32 && Dest == MVT::i64;
912 }
913 
914 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
915   return isZExtFree(Val.getValueType(), VT2);
916 }
917 
918 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
919   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
920   // limited number of native 64-bit operations. Shrinking an operation to fit
921   // in a single 32-bit register should always be helpful. As currently used,
922   // this is much less general than the name suggests, and is only used in
923   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
924   // not profitable, and may actually be harmful.
925   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
926 }
927 
928 //===---------------------------------------------------------------------===//
929 // TargetLowering Callbacks
930 //===---------------------------------------------------------------------===//
931 
932 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
933                                                   bool IsVarArg) {
934   switch (CC) {
935   case CallingConv::AMDGPU_VS:
936   case CallingConv::AMDGPU_GS:
937   case CallingConv::AMDGPU_PS:
938   case CallingConv::AMDGPU_CS:
939   case CallingConv::AMDGPU_HS:
940   case CallingConv::AMDGPU_ES:
941   case CallingConv::AMDGPU_LS:
942     return CC_AMDGPU;
943   case CallingConv::C:
944   case CallingConv::Fast:
945   case CallingConv::Cold:
946     return CC_AMDGPU_Func;
947   case CallingConv::AMDGPU_KERNEL:
948   case CallingConv::SPIR_KERNEL:
949   default:
950     report_fatal_error("Unsupported calling convention for call");
951   }
952 }
953 
954 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
955                                                     bool IsVarArg) {
956   switch (CC) {
957   case CallingConv::AMDGPU_KERNEL:
958   case CallingConv::SPIR_KERNEL:
959     llvm_unreachable("kernels should not be handled here");
960   case CallingConv::AMDGPU_VS:
961   case CallingConv::AMDGPU_GS:
962   case CallingConv::AMDGPU_PS:
963   case CallingConv::AMDGPU_CS:
964   case CallingConv::AMDGPU_HS:
965   case CallingConv::AMDGPU_ES:
966   case CallingConv::AMDGPU_LS:
967     return RetCC_SI_Shader;
968   case CallingConv::C:
969   case CallingConv::Fast:
970   case CallingConv::Cold:
971     return RetCC_AMDGPU_Func;
972   default:
973     report_fatal_error("Unsupported calling convention.");
974   }
975 }
976 
977 /// The SelectionDAGBuilder will automatically promote function arguments
978 /// with illegal types.  However, this does not work for the AMDGPU targets
979 /// since the function arguments are stored in memory as these illegal types.
980 /// In order to handle this properly we need to get the original types sizes
981 /// from the LLVM IR Function and fixup the ISD:InputArg values before
982 /// passing them to AnalyzeFormalArguments()
983 
984 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
985 /// input values across multiple registers.  Each item in the Ins array
986 /// represents a single value that will be stored in registers.  Ins[x].VT is
987 /// the value type of the value that will be stored in the register, so
988 /// whatever SDNode we lower the argument to needs to be this type.
989 ///
990 /// In order to correctly lower the arguments we need to know the size of each
991 /// argument.  Since Ins[x].VT gives us the size of the register that will
992 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
993 /// for the orignal function argument so that we can deduce the correct memory
994 /// type to use for Ins[x].  In most cases the correct memory type will be
995 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
996 /// we have a kernel argument of type v8i8, this argument will be split into
997 /// 8 parts and each part will be represented by its own item in the Ins array.
998 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
999 /// the argument before it was split.  From this, we deduce that the memory type
1000 /// for each individual part is i8.  We pass the memory type as LocVT to the
1001 /// calling convention analysis function and the register type (Ins[x].VT) as
1002 /// the ValVT.
1003 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
1004   CCState &State,
1005   const SmallVectorImpl<ISD::InputArg> &Ins) const {
1006   const MachineFunction &MF = State.getMachineFunction();
1007   const Function &Fn = MF.getFunction();
1008   LLVMContext &Ctx = Fn.getParent()->getContext();
1009   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
1010   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
1011   CallingConv::ID CC = Fn.getCallingConv();
1012 
1013   Align MaxAlign = Align(1);
1014   uint64_t ExplicitArgOffset = 0;
1015   const DataLayout &DL = Fn.getParent()->getDataLayout();
1016 
1017   unsigned InIndex = 0;
1018 
1019   for (const Argument &Arg : Fn.args()) {
1020     Type *BaseArgTy = Arg.getType();
1021     Align Alignment = DL.getABITypeAlign(BaseArgTy);
1022     MaxAlign = std::max(Alignment, MaxAlign);
1023     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
1024 
1025     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Alignment) + ExplicitOffset;
1026     ExplicitArgOffset = alignTo(ExplicitArgOffset, Alignment) + AllocSize;
1027 
1028     // We're basically throwing away everything passed into us and starting over
1029     // to get accurate in-memory offsets. The "PartOffset" is completely useless
1030     // to us as computed in Ins.
1031     //
1032     // We also need to figure out what type legalization is trying to do to get
1033     // the correct memory offsets.
1034 
1035     SmallVector<EVT, 16> ValueVTs;
1036     SmallVector<uint64_t, 16> Offsets;
1037     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
1038 
1039     for (unsigned Value = 0, NumValues = ValueVTs.size();
1040          Value != NumValues; ++Value) {
1041       uint64_t BasePartOffset = Offsets[Value];
1042 
1043       EVT ArgVT = ValueVTs[Value];
1044       EVT MemVT = ArgVT;
1045       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
1046       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
1047 
1048       if (NumRegs == 1) {
1049         // This argument is not split, so the IR type is the memory type.
1050         if (ArgVT.isExtended()) {
1051           // We have an extended type, like i24, so we should just use the
1052           // register type.
1053           MemVT = RegisterVT;
1054         } else {
1055           MemVT = ArgVT;
1056         }
1057       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
1058                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
1059         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
1060         // We have a vector value which has been split into a vector with
1061         // the same scalar type, but fewer elements.  This should handle
1062         // all the floating-point vector types.
1063         MemVT = RegisterVT;
1064       } else if (ArgVT.isVector() &&
1065                  ArgVT.getVectorNumElements() == NumRegs) {
1066         // This arg has been split so that each element is stored in a separate
1067         // register.
1068         MemVT = ArgVT.getScalarType();
1069       } else if (ArgVT.isExtended()) {
1070         // We have an extended type, like i65.
1071         MemVT = RegisterVT;
1072       } else {
1073         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
1074         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
1075         if (RegisterVT.isInteger()) {
1076           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1077         } else if (RegisterVT.isVector()) {
1078           assert(!RegisterVT.getScalarType().isFloatingPoint());
1079           unsigned NumElements = RegisterVT.getVectorNumElements();
1080           assert(MemoryBits % NumElements == 0);
1081           // This vector type has been split into another vector type with
1082           // a different elements size.
1083           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1084                                            MemoryBits / NumElements);
1085           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1086         } else {
1087           llvm_unreachable("cannot deduce memory type.");
1088         }
1089       }
1090 
1091       // Convert one element vectors to scalar.
1092       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1093         MemVT = MemVT.getScalarType();
1094 
1095       // Round up vec3/vec5 argument.
1096       if (MemVT.isVector() && !MemVT.isPow2VectorType()) {
1097         assert(MemVT.getVectorNumElements() == 3 ||
1098                MemVT.getVectorNumElements() == 5);
1099         MemVT = MemVT.getPow2VectorType(State.getContext());
1100       } else if (!MemVT.isSimple() && !MemVT.isVector()) {
1101         MemVT = MemVT.getRoundIntegerType(State.getContext());
1102       }
1103 
1104       unsigned PartOffset = 0;
1105       for (unsigned i = 0; i != NumRegs; ++i) {
1106         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1107                                                BasePartOffset + PartOffset,
1108                                                MemVT.getSimpleVT(),
1109                                                CCValAssign::Full));
1110         PartOffset += MemVT.getStoreSize();
1111       }
1112     }
1113   }
1114 }
1115 
1116 SDValue AMDGPUTargetLowering::LowerReturn(
1117   SDValue Chain, CallingConv::ID CallConv,
1118   bool isVarArg,
1119   const SmallVectorImpl<ISD::OutputArg> &Outs,
1120   const SmallVectorImpl<SDValue> &OutVals,
1121   const SDLoc &DL, SelectionDAG &DAG) const {
1122   // FIXME: Fails for r600 tests
1123   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1124   // "wave terminate should not have return values");
1125   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1126 }
1127 
1128 //===---------------------------------------------------------------------===//
1129 // Target specific lowering
1130 //===---------------------------------------------------------------------===//
1131 
1132 /// Selects the correct CCAssignFn for a given CallingConvention value.
1133 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1134                                                     bool IsVarArg) {
1135   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1136 }
1137 
1138 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1139                                                       bool IsVarArg) {
1140   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1141 }
1142 
1143 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1144                                                   SelectionDAG &DAG,
1145                                                   MachineFrameInfo &MFI,
1146                                                   int ClobberedFI) const {
1147   SmallVector<SDValue, 8> ArgChains;
1148   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1149   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1150 
1151   // Include the original chain at the beginning of the list. When this is
1152   // used by target LowerCall hooks, this helps legalize find the
1153   // CALLSEQ_BEGIN node.
1154   ArgChains.push_back(Chain);
1155 
1156   // Add a chain value for each stack argument corresponding
1157   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1158                             UE = DAG.getEntryNode().getNode()->use_end();
1159        U != UE; ++U) {
1160     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1161       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1162         if (FI->getIndex() < 0) {
1163           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1164           int64_t InLastByte = InFirstByte;
1165           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1166 
1167           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1168               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1169             ArgChains.push_back(SDValue(L, 1));
1170         }
1171       }
1172     }
1173   }
1174 
1175   // Build a tokenfactor for all the chains.
1176   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1177 }
1178 
1179 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1180                                                  SmallVectorImpl<SDValue> &InVals,
1181                                                  StringRef Reason) const {
1182   SDValue Callee = CLI.Callee;
1183   SelectionDAG &DAG = CLI.DAG;
1184 
1185   const Function &Fn = DAG.getMachineFunction().getFunction();
1186 
1187   StringRef FuncName("<unknown>");
1188 
1189   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1190     FuncName = G->getSymbol();
1191   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1192     FuncName = G->getGlobal()->getName();
1193 
1194   DiagnosticInfoUnsupported NoCalls(
1195     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1196   DAG.getContext()->diagnose(NoCalls);
1197 
1198   if (!CLI.IsTailCall) {
1199     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1200       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1201   }
1202 
1203   return DAG.getEntryNode();
1204 }
1205 
1206 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1207                                         SmallVectorImpl<SDValue> &InVals) const {
1208   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1209 }
1210 
1211 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1212                                                       SelectionDAG &DAG) const {
1213   const Function &Fn = DAG.getMachineFunction().getFunction();
1214 
1215   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1216                                             SDLoc(Op).getDebugLoc());
1217   DAG.getContext()->diagnose(NoDynamicAlloca);
1218   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1219   return DAG.getMergeValues(Ops, SDLoc());
1220 }
1221 
1222 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1223                                              SelectionDAG &DAG) const {
1224   switch (Op.getOpcode()) {
1225   default:
1226     Op->print(errs(), &DAG);
1227     llvm_unreachable("Custom lowering code for this"
1228                      "instruction is not implemented yet!");
1229     break;
1230   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1231   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1232   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1233   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1234   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1235   case ISD::FREM: return LowerFREM(Op, DAG);
1236   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1237   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1238   case ISD::FRINT: return LowerFRINT(Op, DAG);
1239   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1240   case ISD::FROUND: return LowerFROUND(Op, DAG);
1241   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1242   case ISD::FLOG:
1243     return LowerFLOG(Op, DAG, numbers::ln2f);
1244   case ISD::FLOG10:
1245     return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
1246   case ISD::FEXP:
1247     return lowerFEXP(Op, DAG);
1248   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1249   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1250   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1251   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1252   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1253   case ISD::CTTZ:
1254   case ISD::CTTZ_ZERO_UNDEF:
1255   case ISD::CTLZ:
1256   case ISD::CTLZ_ZERO_UNDEF:
1257     return LowerCTLZ_CTTZ(Op, DAG);
1258   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1259   }
1260   return Op;
1261 }
1262 
1263 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1264                                               SmallVectorImpl<SDValue> &Results,
1265                                               SelectionDAG &DAG) const {
1266   switch (N->getOpcode()) {
1267   case ISD::SIGN_EXTEND_INREG:
1268     // Different parts of legalization seem to interpret which type of
1269     // sign_extend_inreg is the one to check for custom lowering. The extended
1270     // from type is what really matters, but some places check for custom
1271     // lowering of the result type. This results in trying to use
1272     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1273     // nothing here and let the illegal result integer be handled normally.
1274     return;
1275   default:
1276     return;
1277   }
1278 }
1279 
1280 bool AMDGPUTargetLowering::hasDefinedInitializer(const GlobalValue *GV) {
1281   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1282   if (!GVar || !GVar->hasInitializer())
1283     return false;
1284 
1285   return !isa<UndefValue>(GVar->getInitializer());
1286 }
1287 
1288 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1289                                                  SDValue Op,
1290                                                  SelectionDAG &DAG) const {
1291 
1292   const DataLayout &DL = DAG.getDataLayout();
1293   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1294   const GlobalValue *GV = G->getGlobal();
1295 
1296   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1297       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1298     if (!MFI->isEntryFunction()) {
1299       SDLoc DL(Op);
1300       const Function &Fn = DAG.getMachineFunction().getFunction();
1301       DiagnosticInfoUnsupported BadLDSDecl(
1302         Fn, "local memory global used by non-kernel function",
1303         DL.getDebugLoc(), DS_Warning);
1304       DAG.getContext()->diagnose(BadLDSDecl);
1305 
1306       // We currently don't have a way to correctly allocate LDS objects that
1307       // aren't directly associated with a kernel. We do force inlining of
1308       // functions that use local objects. However, if these dead functions are
1309       // not eliminated, we don't want a compile time error. Just emit a warning
1310       // and a trap, since there should be no callable path here.
1311       SDValue Trap = DAG.getNode(ISD::TRAP, DL, MVT::Other, DAG.getEntryNode());
1312       SDValue OutputChain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
1313                                         Trap, DAG.getRoot());
1314       DAG.setRoot(OutputChain);
1315       return DAG.getUNDEF(Op.getValueType());
1316     }
1317 
1318     // XXX: What does the value of G->getOffset() mean?
1319     assert(G->getOffset() == 0 &&
1320          "Do not know what to do with an non-zero offset");
1321 
1322     // TODO: We could emit code to handle the initialization somewhere.
1323     if (!hasDefinedInitializer(GV)) {
1324       unsigned Offset = MFI->allocateLDSGlobal(DL, *cast<GlobalVariable>(GV));
1325       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1326     }
1327   }
1328 
1329   const Function &Fn = DAG.getMachineFunction().getFunction();
1330   DiagnosticInfoUnsupported BadInit(
1331       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1332   DAG.getContext()->diagnose(BadInit);
1333   return SDValue();
1334 }
1335 
1336 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1337                                                   SelectionDAG &DAG) const {
1338   SmallVector<SDValue, 8> Args;
1339 
1340   EVT VT = Op.getValueType();
1341   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1342     SDLoc SL(Op);
1343     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1344     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1345 
1346     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1347     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1348   }
1349 
1350   for (const SDUse &U : Op->ops())
1351     DAG.ExtractVectorElements(U.get(), Args);
1352 
1353   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1354 }
1355 
1356 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1357                                                      SelectionDAG &DAG) const {
1358 
1359   SmallVector<SDValue, 8> Args;
1360   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1361   EVT VT = Op.getValueType();
1362   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1363                             VT.getVectorNumElements());
1364 
1365   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1366 }
1367 
1368 /// Generate Min/Max node
1369 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1370                                                    SDValue LHS, SDValue RHS,
1371                                                    SDValue True, SDValue False,
1372                                                    SDValue CC,
1373                                                    DAGCombinerInfo &DCI) const {
1374   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1375     return SDValue();
1376 
1377   SelectionDAG &DAG = DCI.DAG;
1378   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1379   switch (CCOpcode) {
1380   case ISD::SETOEQ:
1381   case ISD::SETONE:
1382   case ISD::SETUNE:
1383   case ISD::SETNE:
1384   case ISD::SETUEQ:
1385   case ISD::SETEQ:
1386   case ISD::SETFALSE:
1387   case ISD::SETFALSE2:
1388   case ISD::SETTRUE:
1389   case ISD::SETTRUE2:
1390   case ISD::SETUO:
1391   case ISD::SETO:
1392     break;
1393   case ISD::SETULE:
1394   case ISD::SETULT: {
1395     if (LHS == True)
1396       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1397     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1398   }
1399   case ISD::SETOLE:
1400   case ISD::SETOLT:
1401   case ISD::SETLE:
1402   case ISD::SETLT: {
1403     // Ordered. Assume ordered for undefined.
1404 
1405     // Only do this after legalization to avoid interfering with other combines
1406     // which might occur.
1407     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1408         !DCI.isCalledByLegalizer())
1409       return SDValue();
1410 
1411     // We need to permute the operands to get the correct NaN behavior. The
1412     // selected operand is the second one based on the failing compare with NaN,
1413     // so permute it based on the compare type the hardware uses.
1414     if (LHS == True)
1415       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1416     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1417   }
1418   case ISD::SETUGE:
1419   case ISD::SETUGT: {
1420     if (LHS == True)
1421       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1422     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1423   }
1424   case ISD::SETGT:
1425   case ISD::SETGE:
1426   case ISD::SETOGE:
1427   case ISD::SETOGT: {
1428     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1429         !DCI.isCalledByLegalizer())
1430       return SDValue();
1431 
1432     if (LHS == True)
1433       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1434     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1435   }
1436   case ISD::SETCC_INVALID:
1437     llvm_unreachable("Invalid setcc condcode!");
1438   }
1439   return SDValue();
1440 }
1441 
1442 std::pair<SDValue, SDValue>
1443 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1444   SDLoc SL(Op);
1445 
1446   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1447 
1448   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1449   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1450 
1451   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1452   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1453 
1454   return std::make_pair(Lo, Hi);
1455 }
1456 
1457 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1458   SDLoc SL(Op);
1459 
1460   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1461   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1462   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1463 }
1464 
1465 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1466   SDLoc SL(Op);
1467 
1468   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1469   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1470   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1471 }
1472 
1473 // Split a vector type into two parts. The first part is a power of two vector.
1474 // The second part is whatever is left over, and is a scalar if it would
1475 // otherwise be a 1-vector.
1476 std::pair<EVT, EVT>
1477 AMDGPUTargetLowering::getSplitDestVTs(const EVT &VT, SelectionDAG &DAG) const {
1478   EVT LoVT, HiVT;
1479   EVT EltVT = VT.getVectorElementType();
1480   unsigned NumElts = VT.getVectorNumElements();
1481   unsigned LoNumElts = PowerOf2Ceil((NumElts + 1) / 2);
1482   LoVT = EVT::getVectorVT(*DAG.getContext(), EltVT, LoNumElts);
1483   HiVT = NumElts - LoNumElts == 1
1484              ? EltVT
1485              : EVT::getVectorVT(*DAG.getContext(), EltVT, NumElts - LoNumElts);
1486   return std::make_pair(LoVT, HiVT);
1487 }
1488 
1489 // Split a vector value into two parts of types LoVT and HiVT. HiVT could be
1490 // scalar.
1491 std::pair<SDValue, SDValue>
1492 AMDGPUTargetLowering::splitVector(const SDValue &N, const SDLoc &DL,
1493                                   const EVT &LoVT, const EVT &HiVT,
1494                                   SelectionDAG &DAG) const {
1495   assert(LoVT.getVectorNumElements() +
1496                  (HiVT.isVector() ? HiVT.getVectorNumElements() : 1) <=
1497              N.getValueType().getVectorNumElements() &&
1498          "More vector elements requested than available!");
1499   SDValue Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, LoVT, N,
1500                            DAG.getVectorIdxConstant(0, DL));
1501   SDValue Hi = DAG.getNode(
1502       HiVT.isVector() ? ISD::EXTRACT_SUBVECTOR : ISD::EXTRACT_VECTOR_ELT, DL,
1503       HiVT, N, DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), DL));
1504   return std::make_pair(Lo, Hi);
1505 }
1506 
1507 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1508                                               SelectionDAG &DAG) const {
1509   LoadSDNode *Load = cast<LoadSDNode>(Op);
1510   EVT VT = Op.getValueType();
1511   SDLoc SL(Op);
1512 
1513 
1514   // If this is a 2 element vector, we really want to scalarize and not create
1515   // weird 1 element vectors.
1516   if (VT.getVectorNumElements() == 2) {
1517     SDValue Ops[2];
1518     std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(Load, DAG);
1519     return DAG.getMergeValues(Ops, SL);
1520   }
1521 
1522   SDValue BasePtr = Load->getBasePtr();
1523   EVT MemVT = Load->getMemoryVT();
1524 
1525   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1526 
1527   EVT LoVT, HiVT;
1528   EVT LoMemVT, HiMemVT;
1529   SDValue Lo, Hi;
1530 
1531   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1532   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1533   std::tie(Lo, Hi) = splitVector(Op, SL, LoVT, HiVT, DAG);
1534 
1535   unsigned Size = LoMemVT.getStoreSize();
1536   unsigned BaseAlign = Load->getAlignment();
1537   unsigned HiAlign = MinAlign(BaseAlign, Size);
1538 
1539   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1540                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1541                                   BaseAlign, Load->getMemOperand()->getFlags());
1542   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1543   SDValue HiLoad =
1544       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1545                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1546                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1547 
1548   SDValue Join;
1549   if (LoVT == HiVT) {
1550     // This is the case that the vector is power of two so was evenly split.
1551     Join = DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad);
1552   } else {
1553     Join = DAG.getNode(ISD::INSERT_SUBVECTOR, SL, VT, DAG.getUNDEF(VT), LoLoad,
1554                        DAG.getVectorIdxConstant(0, SL));
1555     Join = DAG.getNode(
1556         HiVT.isVector() ? ISD::INSERT_SUBVECTOR : ISD::INSERT_VECTOR_ELT, SL,
1557         VT, Join, HiLoad,
1558         DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), SL));
1559   }
1560 
1561   SDValue Ops[] = {Join, DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1562                                      LoLoad.getValue(1), HiLoad.getValue(1))};
1563 
1564   return DAG.getMergeValues(Ops, SL);
1565 }
1566 
1567 // Widen a vector load from vec3 to vec4.
1568 SDValue AMDGPUTargetLowering::WidenVectorLoad(SDValue Op,
1569                                               SelectionDAG &DAG) const {
1570   LoadSDNode *Load = cast<LoadSDNode>(Op);
1571   EVT VT = Op.getValueType();
1572   assert(VT.getVectorNumElements() == 3);
1573   SDValue BasePtr = Load->getBasePtr();
1574   EVT MemVT = Load->getMemoryVT();
1575   SDLoc SL(Op);
1576   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1577   unsigned BaseAlign = Load->getAlignment();
1578 
1579   EVT WideVT =
1580       EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(), 4);
1581   EVT WideMemVT =
1582       EVT::getVectorVT(*DAG.getContext(), MemVT.getVectorElementType(), 4);
1583   SDValue WideLoad = DAG.getExtLoad(
1584       Load->getExtensionType(), SL, WideVT, Load->getChain(), BasePtr, SrcValue,
1585       WideMemVT, BaseAlign, Load->getMemOperand()->getFlags());
1586   return DAG.getMergeValues(
1587       {DAG.getNode(ISD::EXTRACT_SUBVECTOR, SL, VT, WideLoad,
1588                    DAG.getVectorIdxConstant(0, SL)),
1589        WideLoad.getValue(1)},
1590       SL);
1591 }
1592 
1593 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1594                                                SelectionDAG &DAG) const {
1595   StoreSDNode *Store = cast<StoreSDNode>(Op);
1596   SDValue Val = Store->getValue();
1597   EVT VT = Val.getValueType();
1598 
1599   // If this is a 2 element vector, we really want to scalarize and not create
1600   // weird 1 element vectors.
1601   if (VT.getVectorNumElements() == 2)
1602     return scalarizeVectorStore(Store, DAG);
1603 
1604   EVT MemVT = Store->getMemoryVT();
1605   SDValue Chain = Store->getChain();
1606   SDValue BasePtr = Store->getBasePtr();
1607   SDLoc SL(Op);
1608 
1609   EVT LoVT, HiVT;
1610   EVT LoMemVT, HiMemVT;
1611   SDValue Lo, Hi;
1612 
1613   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1614   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1615   std::tie(Lo, Hi) = splitVector(Val, SL, LoVT, HiVT, DAG);
1616 
1617   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1618 
1619   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1620   unsigned BaseAlign = Store->getAlignment();
1621   unsigned Size = LoMemVT.getStoreSize();
1622   unsigned HiAlign = MinAlign(BaseAlign, Size);
1623 
1624   SDValue LoStore =
1625       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1626                         Store->getMemOperand()->getFlags());
1627   SDValue HiStore =
1628       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1629                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1630 
1631   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1632 }
1633 
1634 // This is a shortcut for integer division because we have fast i32<->f32
1635 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1636 // float is enough to accurately represent up to a 24-bit signed integer.
1637 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1638                                             bool Sign) const {
1639   SDLoc DL(Op);
1640   EVT VT = Op.getValueType();
1641   SDValue LHS = Op.getOperand(0);
1642   SDValue RHS = Op.getOperand(1);
1643   MVT IntVT = MVT::i32;
1644   MVT FltVT = MVT::f32;
1645 
1646   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1647   if (LHSSignBits < 9)
1648     return SDValue();
1649 
1650   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1651   if (RHSSignBits < 9)
1652     return SDValue();
1653 
1654   unsigned BitSize = VT.getSizeInBits();
1655   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1656   unsigned DivBits = BitSize - SignBits;
1657   if (Sign)
1658     ++DivBits;
1659 
1660   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1661   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1662 
1663   SDValue jq = DAG.getConstant(1, DL, IntVT);
1664 
1665   if (Sign) {
1666     // char|short jq = ia ^ ib;
1667     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1668 
1669     // jq = jq >> (bitsize - 2)
1670     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1671                      DAG.getConstant(BitSize - 2, DL, VT));
1672 
1673     // jq = jq | 0x1
1674     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1675   }
1676 
1677   // int ia = (int)LHS;
1678   SDValue ia = LHS;
1679 
1680   // int ib, (int)RHS;
1681   SDValue ib = RHS;
1682 
1683   // float fa = (float)ia;
1684   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1685 
1686   // float fb = (float)ib;
1687   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1688 
1689   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1690                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1691 
1692   // fq = trunc(fq);
1693   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1694 
1695   // float fqneg = -fq;
1696   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1697 
1698   MachineFunction &MF = DAG.getMachineFunction();
1699   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
1700 
1701   // float fr = mad(fqneg, fb, fa);
1702   unsigned OpCode = !Subtarget->hasMadMacF32Insts() ?
1703                     (unsigned)ISD::FMA :
1704                     !MFI->getMode().allFP32Denormals() ?
1705                     (unsigned)ISD::FMAD :
1706                     (unsigned)AMDGPUISD::FMAD_FTZ;
1707   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1708 
1709   // int iq = (int)fq;
1710   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1711 
1712   // fr = fabs(fr);
1713   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1714 
1715   // fb = fabs(fb);
1716   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1717 
1718   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1719 
1720   // int cv = fr >= fb;
1721   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1722 
1723   // jq = (cv ? jq : 0);
1724   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1725 
1726   // dst = iq + jq;
1727   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1728 
1729   // Rem needs compensation, it's easier to recompute it
1730   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1731   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1732 
1733   // Truncate to number of bits this divide really is.
1734   if (Sign) {
1735     SDValue InRegSize
1736       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1737     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1738     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1739   } else {
1740     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1741     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1742     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1743   }
1744 
1745   return DAG.getMergeValues({ Div, Rem }, DL);
1746 }
1747 
1748 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1749                                       SelectionDAG &DAG,
1750                                       SmallVectorImpl<SDValue> &Results) const {
1751   SDLoc DL(Op);
1752   EVT VT = Op.getValueType();
1753 
1754   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1755 
1756   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1757 
1758   SDValue One = DAG.getConstant(1, DL, HalfVT);
1759   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1760 
1761   //HiLo split
1762   SDValue LHS = Op.getOperand(0);
1763   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1764   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1765 
1766   SDValue RHS = Op.getOperand(1);
1767   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1768   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1769 
1770   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1771       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1772 
1773     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1774                               LHS_Lo, RHS_Lo);
1775 
1776     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1777     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1778 
1779     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1780     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1781     return;
1782   }
1783 
1784   if (isTypeLegal(MVT::i64)) {
1785     MachineFunction &MF = DAG.getMachineFunction();
1786     const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1787 
1788     // Compute denominator reciprocal.
1789     unsigned FMAD = !Subtarget->hasMadMacF32Insts() ?
1790                     (unsigned)ISD::FMA :
1791                     !MFI->getMode().allFP32Denormals() ?
1792                     (unsigned)ISD::FMAD :
1793                     (unsigned)AMDGPUISD::FMAD_FTZ;
1794 
1795     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1796     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1797     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1798       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1799       Cvt_Lo);
1800     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1801     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1802       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1803     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1804       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1805     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1806     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1807       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1808       Mul1);
1809     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1810     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1811     SDValue Rcp64 = DAG.getBitcast(VT,
1812                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1813 
1814     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1815     SDValue One64  = DAG.getConstant(1, DL, VT);
1816     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1817     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1818 
1819     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1820     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1821     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1822     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1823                                     Zero);
1824     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1825                                     One);
1826 
1827     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1828                                   Mulhi1_Lo, Zero1);
1829     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1830                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1831     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1832     SDValue Add1 = DAG.getBitcast(VT,
1833                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1834 
1835     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1836     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1837     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1838                                     Zero);
1839     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1840                                     One);
1841 
1842     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1843                                   Mulhi2_Lo, Zero1);
1844     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1845                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1846     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1847                                   Zero, Add2_Lo.getValue(1));
1848     SDValue Add2 = DAG.getBitcast(VT,
1849                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1850     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1851 
1852     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1853 
1854     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1855     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1856     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1857                                   Mul3_Lo, Zero1);
1858     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1859                                   Mul3_Hi, Sub1_Lo.getValue(1));
1860     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1861     SDValue Sub1 = DAG.getBitcast(VT,
1862                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1863 
1864     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1865     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1866                                  ISD::SETUGE);
1867     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1868                                  ISD::SETUGE);
1869     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1870 
1871     // TODO: Here and below portions of the code can be enclosed into if/endif.
1872     // Currently control flow is unconditional and we have 4 selects after
1873     // potential endif to substitute PHIs.
1874 
1875     // if C3 != 0 ...
1876     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1877                                   RHS_Lo, Zero1);
1878     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1879                                   RHS_Hi, Sub1_Lo.getValue(1));
1880     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1881                                   Zero, Sub2_Lo.getValue(1));
1882     SDValue Sub2 = DAG.getBitcast(VT,
1883                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1884 
1885     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1886 
1887     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1888                                  ISD::SETUGE);
1889     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1890                                  ISD::SETUGE);
1891     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1892 
1893     // if (C6 != 0)
1894     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1895 
1896     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1897                                   RHS_Lo, Zero1);
1898     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1899                                   RHS_Hi, Sub2_Lo.getValue(1));
1900     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1901                                   Zero, Sub3_Lo.getValue(1));
1902     SDValue Sub3 = DAG.getBitcast(VT,
1903                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1904 
1905     // endif C6
1906     // endif C3
1907 
1908     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1909     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1910 
1911     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1912     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1913 
1914     Results.push_back(Div);
1915     Results.push_back(Rem);
1916 
1917     return;
1918   }
1919 
1920   // r600 expandion.
1921   // Get Speculative values
1922   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1923   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1924 
1925   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1926   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1927   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1928 
1929   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1930   SDValue DIV_Lo = Zero;
1931 
1932   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1933 
1934   for (unsigned i = 0; i < halfBitWidth; ++i) {
1935     const unsigned bitPos = halfBitWidth - i - 1;
1936     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1937     // Get value of high bit
1938     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1939     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1940     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1941 
1942     // Shift
1943     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1944     // Add LHS high bit
1945     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1946 
1947     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1948     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1949 
1950     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1951 
1952     // Update REM
1953     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1954     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1955   }
1956 
1957   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1958   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1959   Results.push_back(DIV);
1960   Results.push_back(REM);
1961 }
1962 
1963 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1964                                            SelectionDAG &DAG) const {
1965   SDLoc DL(Op);
1966   EVT VT = Op.getValueType();
1967 
1968   if (VT == MVT::i64) {
1969     SmallVector<SDValue, 2> Results;
1970     LowerUDIVREM64(Op, DAG, Results);
1971     return DAG.getMergeValues(Results, DL);
1972   }
1973 
1974   if (VT == MVT::i32) {
1975     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1976       return Res;
1977   }
1978 
1979   SDValue Num = Op.getOperand(0);
1980   SDValue Den = Op.getOperand(1);
1981 
1982   // RCP =  URECIP(Den) = 2^32 / Den + e
1983   // e is rounding error.
1984   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1985 
1986   // RCP_LO = mul(RCP, Den) */
1987   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1988 
1989   // RCP_HI = mulhu (RCP, Den) */
1990   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1991 
1992   // NEG_RCP_LO = -RCP_LO
1993   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1994                                                      RCP_LO);
1995 
1996   const SDValue Zero = DAG.getConstant(0, DL, VT);
1997   const EVT CCVT = getSetCCResultType(DAG.getDataLayout(),
1998                                       *DAG.getContext(), VT);
1999 
2000   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
2001   SDValue CmpRcpHiZero = DAG.getSetCC(DL, CCVT, RCP_HI, Zero, ISD::SETEQ);
2002   SDValue ABS_RCP_LO = DAG.getNode(ISD::SELECT,
2003                                    DL, VT, CmpRcpHiZero, NEG_RCP_LO, RCP_LO);
2004 
2005   // Calculate the rounding error from the URECIP instruction
2006   // E = mulhu(ABS_RCP_LO, RCP)
2007   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
2008 
2009   // RCP_A_E = RCP + E
2010   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
2011 
2012   // RCP_S_E = RCP - E
2013   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
2014 
2015   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
2016   SDValue Tmp0 = DAG.getNode(ISD::SELECT, DL, VT,
2017                              CmpRcpHiZero, RCP_A_E, RCP_S_E);
2018 
2019   // Quotient = mulhu(Tmp0, Num)
2020   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
2021 
2022   // Num_S_Remainder = Quotient * Den
2023   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
2024 
2025   // Remainder = Num - Num_S_Remainder
2026   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
2027 
2028   // Remainder_GE_Den = (Remainder >= Den)
2029   SDValue Remainder_GE_Den = DAG.getSetCC(DL, CCVT, Remainder, Den, ISD::SETUGE);
2030 
2031   // Remainder_GE_Zero = (Num >= Num_S_Remainder)
2032   SDValue Remainder_GE_Zero = DAG.getSetCC(DL, CCVT, Num, Num_S_Remainder,
2033                                            ISD::SETUGE);
2034 
2035   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
2036   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, CCVT, Remainder_GE_Den,
2037                              Remainder_GE_Zero);
2038 
2039   // Calculate Division result:
2040 
2041   // Quotient_A_One = Quotient + 1
2042   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
2043                                        DAG.getConstant(1, DL, VT));
2044 
2045   // Quotient_S_One = Quotient - 1
2046   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
2047                                        DAG.getConstant(1, DL, VT));
2048 
2049   // Div = (Tmp1 ? Quotient_A_One : Quotient)
2050   SDValue Div = DAG.getNode(ISD::SELECT, DL, VT, Tmp1,
2051                             Quotient_A_One, Quotient);
2052 
2053   // Div = (Remainder_GE_Zero ? Div : Quotient_S_One)
2054   Div = DAG.getNode(ISD::SELECT, DL, VT, Remainder_GE_Zero,
2055                     Div, Quotient_S_One);
2056 
2057   // Calculate Rem result:
2058 
2059   // Remainder_S_Den = Remainder - Den
2060   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
2061 
2062   // Remainder_A_Den = Remainder + Den
2063   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
2064 
2065   // Rem = (Tmp1 ? Remainder_S_Den : Remainder)
2066   SDValue Rem = DAG.getNode(ISD::SELECT, DL, VT, Tmp1,
2067                             Remainder_S_Den, Remainder);
2068 
2069   // Rem = (Remainder_GE_Zero ? Rem : Remainder_A_Den)
2070   Rem = DAG.getNode(ISD::SELECT, DL, VT,
2071                     Remainder_GE_Zero, Rem, Remainder_A_Den);
2072   SDValue Ops[2] = {
2073     Div,
2074     Rem
2075   };
2076   return DAG.getMergeValues(Ops, DL);
2077 }
2078 
2079 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
2080                                            SelectionDAG &DAG) const {
2081   SDLoc DL(Op);
2082   EVT VT = Op.getValueType();
2083 
2084   SDValue LHS = Op.getOperand(0);
2085   SDValue RHS = Op.getOperand(1);
2086 
2087   SDValue Zero = DAG.getConstant(0, DL, VT);
2088   SDValue NegOne = DAG.getConstant(-1, DL, VT);
2089 
2090   if (VT == MVT::i32) {
2091     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
2092       return Res;
2093   }
2094 
2095   if (VT == MVT::i64 &&
2096       DAG.ComputeNumSignBits(LHS) > 32 &&
2097       DAG.ComputeNumSignBits(RHS) > 32) {
2098     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
2099 
2100     //HiLo split
2101     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
2102     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
2103     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
2104                                  LHS_Lo, RHS_Lo);
2105     SDValue Res[2] = {
2106       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
2107       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
2108     };
2109     return DAG.getMergeValues(Res, DL);
2110   }
2111 
2112   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
2113   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
2114   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
2115   SDValue RSign = LHSign; // Remainder sign is the same as LHS
2116 
2117   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
2118   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
2119 
2120   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
2121   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
2122 
2123   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
2124   SDValue Rem = Div.getValue(1);
2125 
2126   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
2127   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
2128 
2129   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
2130   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
2131 
2132   SDValue Res[2] = {
2133     Div,
2134     Rem
2135   };
2136   return DAG.getMergeValues(Res, DL);
2137 }
2138 
2139 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2140 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2141   SDLoc SL(Op);
2142   EVT VT = Op.getValueType();
2143   SDValue X = Op.getOperand(0);
2144   SDValue Y = Op.getOperand(1);
2145 
2146   // TODO: Should this propagate fast-math-flags?
2147 
2148   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2149   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2150   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2151 
2152   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2153 }
2154 
2155 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2156   SDLoc SL(Op);
2157   SDValue Src = Op.getOperand(0);
2158 
2159   // result = trunc(src)
2160   // if (src > 0.0 && src != result)
2161   //   result += 1.0
2162 
2163   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2164 
2165   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2166   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2167 
2168   EVT SetCCVT =
2169       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2170 
2171   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2172   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2173   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2174 
2175   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2176   // TODO: Should this propagate fast-math-flags?
2177   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2178 }
2179 
2180 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2181                                   SelectionDAG &DAG) {
2182   const unsigned FractBits = 52;
2183   const unsigned ExpBits = 11;
2184 
2185   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2186                                 Hi,
2187                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2188                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2189   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2190                             DAG.getConstant(1023, SL, MVT::i32));
2191 
2192   return Exp;
2193 }
2194 
2195 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2196   SDLoc SL(Op);
2197   SDValue Src = Op.getOperand(0);
2198 
2199   assert(Op.getValueType() == MVT::f64);
2200 
2201   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2202   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2203 
2204   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2205 
2206   // Extract the upper half, since this is where we will find the sign and
2207   // exponent.
2208   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2209 
2210   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2211 
2212   const unsigned FractBits = 52;
2213 
2214   // Extract the sign bit.
2215   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2216   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2217 
2218   // Extend back to 64-bits.
2219   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2220   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2221 
2222   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2223   const SDValue FractMask
2224     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2225 
2226   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2227   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2228   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2229 
2230   EVT SetCCVT =
2231       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2232 
2233   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2234 
2235   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2236   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2237 
2238   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2239   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2240 
2241   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2242 }
2243 
2244 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2245   SDLoc SL(Op);
2246   SDValue Src = Op.getOperand(0);
2247 
2248   assert(Op.getValueType() == MVT::f64);
2249 
2250   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2251   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2252   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2253 
2254   // TODO: Should this propagate fast-math-flags?
2255 
2256   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2257   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2258 
2259   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2260 
2261   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2262   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2263 
2264   EVT SetCCVT =
2265       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2266   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2267 
2268   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2269 }
2270 
2271 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2272   // FNEARBYINT and FRINT are the same, except in their handling of FP
2273   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2274   // rint, so just treat them as equivalent.
2275   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2276 }
2277 
2278 // XXX - May require not supporting f32 denormals?
2279 
2280 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2281 // compare and vselect end up producing worse code than scalarizing the whole
2282 // operation.
2283 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2284   SDLoc SL(Op);
2285   SDValue X = Op.getOperand(0);
2286   EVT VT = Op.getValueType();
2287 
2288   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2289 
2290   // TODO: Should this propagate fast-math-flags?
2291 
2292   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2293 
2294   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2295 
2296   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2297   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2298   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2299 
2300   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2301 
2302   EVT SetCCVT =
2303       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2304 
2305   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2306 
2307   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2308 
2309   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2310 }
2311 
2312 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2313   SDLoc SL(Op);
2314   SDValue Src = Op.getOperand(0);
2315 
2316   // result = trunc(src);
2317   // if (src < 0.0 && src != result)
2318   //   result += -1.0.
2319 
2320   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2321 
2322   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2323   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2324 
2325   EVT SetCCVT =
2326       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2327 
2328   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2329   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2330   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2331 
2332   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2333   // TODO: Should this propagate fast-math-flags?
2334   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2335 }
2336 
2337 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2338                                         double Log2BaseInverted) const {
2339   EVT VT = Op.getValueType();
2340 
2341   SDLoc SL(Op);
2342   SDValue Operand = Op.getOperand(0);
2343   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2344   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2345 
2346   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2347 }
2348 
2349 // exp2(M_LOG2E_F * f);
2350 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2351   EVT VT = Op.getValueType();
2352   SDLoc SL(Op);
2353   SDValue Src = Op.getOperand(0);
2354 
2355   const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
2356   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2357   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2358 }
2359 
2360 static bool isCtlzOpc(unsigned Opc) {
2361   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2362 }
2363 
2364 static bool isCttzOpc(unsigned Opc) {
2365   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2366 }
2367 
2368 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2369   SDLoc SL(Op);
2370   SDValue Src = Op.getOperand(0);
2371   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2372                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2373 
2374   unsigned ISDOpc, NewOpc;
2375   if (isCtlzOpc(Op.getOpcode())) {
2376     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2377     NewOpc = AMDGPUISD::FFBH_U32;
2378   } else if (isCttzOpc(Op.getOpcode())) {
2379     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2380     NewOpc = AMDGPUISD::FFBL_B32;
2381   } else
2382     llvm_unreachable("Unexpected OPCode!!!");
2383 
2384 
2385   if (ZeroUndef && Src.getValueType() == MVT::i32)
2386     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2387 
2388   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2389 
2390   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2391   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2392 
2393   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2394   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2395 
2396   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2397                                    *DAG.getContext(), MVT::i32);
2398 
2399   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2400   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2401 
2402   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2403   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2404 
2405   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2406   SDValue Add, NewOpr;
2407   if (isCtlzOpc(Op.getOpcode())) {
2408     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2409     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2410     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2411   } else {
2412     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2413     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2414     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2415   }
2416 
2417   if (!ZeroUndef) {
2418     // Test if the full 64-bit input is zero.
2419 
2420     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2421     // which we probably don't want.
2422     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2423     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2424     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2425 
2426     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2427     // with the same cycles, otherwise it is slower.
2428     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2429     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2430 
2431     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2432 
2433     // The instruction returns -1 for 0 input, but the defined intrinsic
2434     // behavior is to return the number of bits.
2435     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2436                          SrcIsZero, Bits32, NewOpr);
2437   }
2438 
2439   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2440 }
2441 
2442 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2443                                                bool Signed) const {
2444   // Unsigned
2445   // cul2f(ulong u)
2446   //{
2447   //  uint lz = clz(u);
2448   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2449   //  u = (u << lz) & 0x7fffffffffffffffUL;
2450   //  ulong t = u & 0xffffffffffUL;
2451   //  uint v = (e << 23) | (uint)(u >> 40);
2452   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2453   //  return as_float(v + r);
2454   //}
2455   // Signed
2456   // cl2f(long l)
2457   //{
2458   //  long s = l >> 63;
2459   //  float r = cul2f((l + s) ^ s);
2460   //  return s ? -r : r;
2461   //}
2462 
2463   SDLoc SL(Op);
2464   SDValue Src = Op.getOperand(0);
2465   SDValue L = Src;
2466 
2467   SDValue S;
2468   if (Signed) {
2469     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2470     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2471 
2472     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2473     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2474   }
2475 
2476   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2477                                    *DAG.getContext(), MVT::f32);
2478 
2479 
2480   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2481   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2482   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2483   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2484 
2485   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2486   SDValue E = DAG.getSelect(SL, MVT::i32,
2487     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2488     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2489     ZeroI32);
2490 
2491   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2492     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2493     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2494 
2495   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2496                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2497 
2498   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2499                              U, DAG.getConstant(40, SL, MVT::i64));
2500 
2501   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2502     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2503     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2504 
2505   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2506   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2507   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2508 
2509   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2510 
2511   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2512 
2513   SDValue R = DAG.getSelect(SL, MVT::i32,
2514     RCmp,
2515     One,
2516     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2517   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2518   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2519 
2520   if (!Signed)
2521     return R;
2522 
2523   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2524   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2525 }
2526 
2527 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2528                                                bool Signed) const {
2529   SDLoc SL(Op);
2530   SDValue Src = Op.getOperand(0);
2531 
2532   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2533 
2534   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2535                            DAG.getConstant(0, SL, MVT::i32));
2536   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2537                            DAG.getConstant(1, SL, MVT::i32));
2538 
2539   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2540                               SL, MVT::f64, Hi);
2541 
2542   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2543 
2544   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2545                               DAG.getConstant(32, SL, MVT::i32));
2546   // TODO: Should this propagate fast-math-flags?
2547   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2548 }
2549 
2550 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2551                                                SelectionDAG &DAG) const {
2552   // TODO: Factor out code common with LowerSINT_TO_FP.
2553   EVT DestVT = Op.getValueType();
2554   SDValue Src = Op.getOperand(0);
2555   EVT SrcVT = Src.getValueType();
2556 
2557   if (SrcVT == MVT::i16) {
2558     if (DestVT == MVT::f16)
2559       return Op;
2560     SDLoc DL(Op);
2561 
2562     // Promote src to i32
2563     SDValue Ext = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Src);
2564     return DAG.getNode(ISD::UINT_TO_FP, DL, DestVT, Ext);
2565   }
2566 
2567   assert(SrcVT == MVT::i64 && "operation should be legal");
2568 
2569   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2570     SDLoc DL(Op);
2571 
2572     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2573     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2574     SDValue FPRound =
2575         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2576 
2577     return FPRound;
2578   }
2579 
2580   if (DestVT == MVT::f32)
2581     return LowerINT_TO_FP32(Op, DAG, false);
2582 
2583   assert(DestVT == MVT::f64);
2584   return LowerINT_TO_FP64(Op, DAG, false);
2585 }
2586 
2587 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2588                                               SelectionDAG &DAG) const {
2589   EVT DestVT = Op.getValueType();
2590 
2591   SDValue Src = Op.getOperand(0);
2592   EVT SrcVT = Src.getValueType();
2593 
2594   if (SrcVT == MVT::i16) {
2595     if (DestVT == MVT::f16)
2596       return Op;
2597 
2598     SDLoc DL(Op);
2599     // Promote src to i32
2600     SDValue Ext = DAG.getNode(ISD::SIGN_EXTEND, DL, MVT::i32, Src);
2601     return DAG.getNode(ISD::SINT_TO_FP, DL, DestVT, Ext);
2602   }
2603 
2604   assert(SrcVT == MVT::i64 && "operation should be legal");
2605 
2606   // TODO: Factor out code common with LowerUINT_TO_FP.
2607 
2608   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2609     SDLoc DL(Op);
2610     SDValue Src = Op.getOperand(0);
2611 
2612     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2613     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2614     SDValue FPRound =
2615         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2616 
2617     return FPRound;
2618   }
2619 
2620   if (DestVT == MVT::f32)
2621     return LowerINT_TO_FP32(Op, DAG, true);
2622 
2623   assert(DestVT == MVT::f64);
2624   return LowerINT_TO_FP64(Op, DAG, true);
2625 }
2626 
2627 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2628                                                bool Signed) const {
2629   SDLoc SL(Op);
2630 
2631   SDValue Src = Op.getOperand(0);
2632 
2633   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2634 
2635   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2636                                  MVT::f64);
2637   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2638                                  MVT::f64);
2639   // TODO: Should this propagate fast-math-flags?
2640   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2641 
2642   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2643 
2644 
2645   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2646 
2647   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2648                            MVT::i32, FloorMul);
2649   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2650 
2651   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2652 
2653   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2654 }
2655 
2656 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2657   SDLoc DL(Op);
2658   SDValue N0 = Op.getOperand(0);
2659 
2660   // Convert to target node to get known bits
2661   if (N0.getValueType() == MVT::f32)
2662     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2663 
2664   if (getTargetMachine().Options.UnsafeFPMath) {
2665     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2666     return SDValue();
2667   }
2668 
2669   assert(N0.getSimpleValueType() == MVT::f64);
2670 
2671   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2672   const unsigned ExpMask = 0x7ff;
2673   const unsigned ExpBiasf64 = 1023;
2674   const unsigned ExpBiasf16 = 15;
2675   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2676   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2677   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2678   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2679                            DAG.getConstant(32, DL, MVT::i64));
2680   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2681   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2682   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2683                           DAG.getConstant(20, DL, MVT::i64));
2684   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2685                   DAG.getConstant(ExpMask, DL, MVT::i32));
2686   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2687   // add the f16 bias (15) to get the biased exponent for the f16 format.
2688   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2689                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2690 
2691   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2692                           DAG.getConstant(8, DL, MVT::i32));
2693   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2694                   DAG.getConstant(0xffe, DL, MVT::i32));
2695 
2696   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2697                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2698   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2699 
2700   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2701   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2702 
2703   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2704   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2705       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2706                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2707 
2708   // N = M | (E << 12);
2709   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2710       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2711                   DAG.getConstant(12, DL, MVT::i32)));
2712 
2713   // B = clamp(1-E, 0, 13);
2714   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2715                                   One, E);
2716   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2717   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2718                   DAG.getConstant(13, DL, MVT::i32));
2719 
2720   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2721                                    DAG.getConstant(0x1000, DL, MVT::i32));
2722 
2723   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2724   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2725   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2726   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2727 
2728   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2729   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2730                               DAG.getConstant(0x7, DL, MVT::i32));
2731   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2732                   DAG.getConstant(2, DL, MVT::i32));
2733   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2734                                One, Zero, ISD::SETEQ);
2735   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2736                                One, Zero, ISD::SETGT);
2737   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2738   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2739 
2740   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2741                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2742   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2743                       I, V, ISD::SETEQ);
2744 
2745   // Extract the sign bit.
2746   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2747                             DAG.getConstant(16, DL, MVT::i32));
2748   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2749                      DAG.getConstant(0x8000, DL, MVT::i32));
2750 
2751   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2752   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2753 }
2754 
2755 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2756                                               SelectionDAG &DAG) const {
2757   SDValue Src = Op.getOperand(0);
2758 
2759   // TODO: Factor out code common with LowerFP_TO_UINT.
2760 
2761   EVT SrcVT = Src.getValueType();
2762   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2763     SDLoc DL(Op);
2764 
2765     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2766     SDValue FpToInt32 =
2767         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2768 
2769     return FpToInt32;
2770   }
2771 
2772   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2773     return LowerFP64_TO_INT(Op, DAG, true);
2774 
2775   return SDValue();
2776 }
2777 
2778 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2779                                               SelectionDAG &DAG) const {
2780   SDValue Src = Op.getOperand(0);
2781 
2782   // TODO: Factor out code common with LowerFP_TO_SINT.
2783 
2784   EVT SrcVT = Src.getValueType();
2785   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2786     SDLoc DL(Op);
2787 
2788     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2789     SDValue FpToInt32 =
2790         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2791 
2792     return FpToInt32;
2793   }
2794 
2795   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2796     return LowerFP64_TO_INT(Op, DAG, false);
2797 
2798   return SDValue();
2799 }
2800 
2801 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2802                                                      SelectionDAG &DAG) const {
2803   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2804   MVT VT = Op.getSimpleValueType();
2805   MVT ScalarVT = VT.getScalarType();
2806 
2807   assert(VT.isVector());
2808 
2809   SDValue Src = Op.getOperand(0);
2810   SDLoc DL(Op);
2811 
2812   // TODO: Don't scalarize on Evergreen?
2813   unsigned NElts = VT.getVectorNumElements();
2814   SmallVector<SDValue, 8> Args;
2815   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2816 
2817   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2818   for (unsigned I = 0; I < NElts; ++I)
2819     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2820 
2821   return DAG.getBuildVector(VT, DL, Args);
2822 }
2823 
2824 //===----------------------------------------------------------------------===//
2825 // Custom DAG optimizations
2826 //===----------------------------------------------------------------------===//
2827 
2828 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2829   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2830 }
2831 
2832 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2833   EVT VT = Op.getValueType();
2834   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2835                                      // as unsigned 24-bit values.
2836     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2837 }
2838 
2839 static SDValue simplifyI24(SDNode *Node24,
2840                            TargetLowering::DAGCombinerInfo &DCI) {
2841   SelectionDAG &DAG = DCI.DAG;
2842   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2843   bool IsIntrin = Node24->getOpcode() == ISD::INTRINSIC_WO_CHAIN;
2844 
2845   SDValue LHS = IsIntrin ? Node24->getOperand(1) : Node24->getOperand(0);
2846   SDValue RHS = IsIntrin ? Node24->getOperand(2) : Node24->getOperand(1);
2847   unsigned NewOpcode = Node24->getOpcode();
2848   if (IsIntrin) {
2849     unsigned IID = cast<ConstantSDNode>(Node24->getOperand(0))->getZExtValue();
2850     NewOpcode = IID == Intrinsic::amdgcn_mul_i24 ?
2851       AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
2852   }
2853 
2854   APInt Demanded = APInt::getLowBitsSet(LHS.getValueSizeInBits(), 24);
2855 
2856   // First try to simplify using SimplifyMultipleUseDemandedBits which allows
2857   // the operands to have other uses, but will only perform simplifications that
2858   // involve bypassing some nodes for this user.
2859   SDValue DemandedLHS = TLI.SimplifyMultipleUseDemandedBits(LHS, Demanded, DAG);
2860   SDValue DemandedRHS = TLI.SimplifyMultipleUseDemandedBits(RHS, Demanded, DAG);
2861   if (DemandedLHS || DemandedRHS)
2862     return DAG.getNode(NewOpcode, SDLoc(Node24), Node24->getVTList(),
2863                        DemandedLHS ? DemandedLHS : LHS,
2864                        DemandedRHS ? DemandedRHS : RHS);
2865 
2866   // Now try SimplifyDemandedBits which can simplify the nodes used by our
2867   // operands if this node is the only user.
2868   if (TLI.SimplifyDemandedBits(LHS, Demanded, DCI))
2869     return SDValue(Node24, 0);
2870   if (TLI.SimplifyDemandedBits(RHS, Demanded, DCI))
2871     return SDValue(Node24, 0);
2872 
2873   return SDValue();
2874 }
2875 
2876 template <typename IntTy>
2877 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2878                                uint32_t Width, const SDLoc &DL) {
2879   if (Width + Offset < 32) {
2880     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2881     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2882     return DAG.getConstant(Result, DL, MVT::i32);
2883   }
2884 
2885   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2886 }
2887 
2888 static bool hasVolatileUser(SDNode *Val) {
2889   for (SDNode *U : Val->uses()) {
2890     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2891       if (M->isVolatile())
2892         return true;
2893     }
2894   }
2895 
2896   return false;
2897 }
2898 
2899 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2900   // i32 vectors are the canonical memory type.
2901   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2902     return false;
2903 
2904   if (!VT.isByteSized())
2905     return false;
2906 
2907   unsigned Size = VT.getStoreSize();
2908 
2909   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2910     return false;
2911 
2912   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2913     return false;
2914 
2915   return true;
2916 }
2917 
2918 // Replace load of an illegal type with a store of a bitcast to a friendlier
2919 // type.
2920 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2921                                                  DAGCombinerInfo &DCI) const {
2922   if (!DCI.isBeforeLegalize())
2923     return SDValue();
2924 
2925   LoadSDNode *LN = cast<LoadSDNode>(N);
2926   if (!LN->isSimple() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2927     return SDValue();
2928 
2929   SDLoc SL(N);
2930   SelectionDAG &DAG = DCI.DAG;
2931   EVT VT = LN->getMemoryVT();
2932 
2933   unsigned Size = VT.getStoreSize();
2934   Align Alignment = LN->getAlign();
2935   if (Alignment < Size && isTypeLegal(VT)) {
2936     bool IsFast;
2937     unsigned AS = LN->getAddressSpace();
2938 
2939     // Expand unaligned loads earlier than legalization. Due to visitation order
2940     // problems during legalization, the emitted instructions to pack and unpack
2941     // the bytes again are not eliminated in the case of an unaligned copy.
2942     if (!allowsMisalignedMemoryAccesses(VT, AS, Alignment.value(),
2943                                         LN->getMemOperand()->getFlags(),
2944                                         &IsFast)) {
2945       SDValue Ops[2];
2946 
2947       if (VT.isVector())
2948         std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(LN, DAG);
2949       else
2950         std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2951 
2952       return DAG.getMergeValues(Ops, SDLoc(N));
2953     }
2954 
2955     if (!IsFast)
2956       return SDValue();
2957   }
2958 
2959   if (!shouldCombineMemoryType(VT))
2960     return SDValue();
2961 
2962   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2963 
2964   SDValue NewLoad
2965     = DAG.getLoad(NewVT, SL, LN->getChain(),
2966                   LN->getBasePtr(), LN->getMemOperand());
2967 
2968   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2969   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2970   return SDValue(N, 0);
2971 }
2972 
2973 // Replace store of an illegal type with a store of a bitcast to a friendlier
2974 // type.
2975 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2976                                                   DAGCombinerInfo &DCI) const {
2977   if (!DCI.isBeforeLegalize())
2978     return SDValue();
2979 
2980   StoreSDNode *SN = cast<StoreSDNode>(N);
2981   if (!SN->isSimple() || !ISD::isNormalStore(SN))
2982     return SDValue();
2983 
2984   EVT VT = SN->getMemoryVT();
2985   unsigned Size = VT.getStoreSize();
2986 
2987   SDLoc SL(N);
2988   SelectionDAG &DAG = DCI.DAG;
2989   Align Alignment = SN->getAlign();
2990   if (Alignment < Size && isTypeLegal(VT)) {
2991     bool IsFast;
2992     unsigned AS = SN->getAddressSpace();
2993 
2994     // Expand unaligned stores earlier than legalization. Due to visitation
2995     // order problems during legalization, the emitted instructions to pack and
2996     // unpack the bytes again are not eliminated in the case of an unaligned
2997     // copy.
2998     if (!allowsMisalignedMemoryAccesses(VT, AS, Alignment.value(),
2999                                         SN->getMemOperand()->getFlags(),
3000                                         &IsFast)) {
3001       if (VT.isVector())
3002         return scalarizeVectorStore(SN, DAG);
3003 
3004       return expandUnalignedStore(SN, DAG);
3005     }
3006 
3007     if (!IsFast)
3008       return SDValue();
3009   }
3010 
3011   if (!shouldCombineMemoryType(VT))
3012     return SDValue();
3013 
3014   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
3015   SDValue Val = SN->getValue();
3016 
3017   //DCI.AddToWorklist(Val.getNode());
3018 
3019   bool OtherUses = !Val.hasOneUse();
3020   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
3021   if (OtherUses) {
3022     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
3023     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
3024   }
3025 
3026   return DAG.getStore(SN->getChain(), SL, CastVal,
3027                       SN->getBasePtr(), SN->getMemOperand());
3028 }
3029 
3030 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
3031 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
3032 // issues.
3033 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
3034                                                         DAGCombinerInfo &DCI) const {
3035   SelectionDAG &DAG = DCI.DAG;
3036   SDValue N0 = N->getOperand(0);
3037 
3038   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
3039   //     (vt2 (truncate (assertzext vt0:x, vt1)))
3040   if (N0.getOpcode() == ISD::TRUNCATE) {
3041     SDValue N1 = N->getOperand(1);
3042     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
3043     SDLoc SL(N);
3044 
3045     SDValue Src = N0.getOperand(0);
3046     EVT SrcVT = Src.getValueType();
3047     if (SrcVT.bitsGE(ExtVT)) {
3048       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
3049       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
3050     }
3051   }
3052 
3053   return SDValue();
3054 }
3055 
3056 SDValue AMDGPUTargetLowering::performIntrinsicWOChainCombine(
3057   SDNode *N, DAGCombinerInfo &DCI) const {
3058   unsigned IID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
3059   switch (IID) {
3060   case Intrinsic::amdgcn_mul_i24:
3061   case Intrinsic::amdgcn_mul_u24:
3062     return simplifyI24(N, DCI);
3063   case Intrinsic::amdgcn_fract:
3064   case Intrinsic::amdgcn_rsq:
3065   case Intrinsic::amdgcn_rcp_legacy:
3066   case Intrinsic::amdgcn_rsq_legacy:
3067   case Intrinsic::amdgcn_rsq_clamp:
3068   case Intrinsic::amdgcn_ldexp: {
3069     // FIXME: This is probably wrong. If src is an sNaN, it won't be quieted
3070     SDValue Src = N->getOperand(1);
3071     return Src.isUndef() ? Src : SDValue();
3072   }
3073   default:
3074     return SDValue();
3075   }
3076 }
3077 
3078 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
3079 /// binary operation \p Opc to it with the corresponding constant operands.
3080 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
3081   DAGCombinerInfo &DCI, const SDLoc &SL,
3082   unsigned Opc, SDValue LHS,
3083   uint32_t ValLo, uint32_t ValHi) const {
3084   SelectionDAG &DAG = DCI.DAG;
3085   SDValue Lo, Hi;
3086   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
3087 
3088   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
3089   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
3090 
3091   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
3092   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
3093 
3094   // Re-visit the ands. It's possible we eliminated one of them and it could
3095   // simplify the vector.
3096   DCI.AddToWorklist(Lo.getNode());
3097   DCI.AddToWorklist(Hi.getNode());
3098 
3099   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
3100   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3101 }
3102 
3103 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
3104                                                 DAGCombinerInfo &DCI) const {
3105   EVT VT = N->getValueType(0);
3106 
3107   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3108   if (!RHS)
3109     return SDValue();
3110 
3111   SDValue LHS = N->getOperand(0);
3112   unsigned RHSVal = RHS->getZExtValue();
3113   if (!RHSVal)
3114     return LHS;
3115 
3116   SDLoc SL(N);
3117   SelectionDAG &DAG = DCI.DAG;
3118 
3119   switch (LHS->getOpcode()) {
3120   default:
3121     break;
3122   case ISD::ZERO_EXTEND:
3123   case ISD::SIGN_EXTEND:
3124   case ISD::ANY_EXTEND: {
3125     SDValue X = LHS->getOperand(0);
3126 
3127     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
3128         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
3129       // Prefer build_vector as the canonical form if packed types are legal.
3130       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
3131       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
3132        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
3133       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
3134     }
3135 
3136     // shl (ext x) => zext (shl x), if shift does not overflow int
3137     if (VT != MVT::i64)
3138       break;
3139     KnownBits Known = DAG.computeKnownBits(X);
3140     unsigned LZ = Known.countMinLeadingZeros();
3141     if (LZ < RHSVal)
3142       break;
3143     EVT XVT = X.getValueType();
3144     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
3145     return DAG.getZExtOrTrunc(Shl, SL, VT);
3146   }
3147   }
3148 
3149   if (VT != MVT::i64)
3150     return SDValue();
3151 
3152   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3153 
3154   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3155   // common case, splitting this into a move and a 32-bit shift is faster and
3156   // the same code size.
3157   if (RHSVal < 32)
3158     return SDValue();
3159 
3160   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3161 
3162   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3163   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3164 
3165   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3166 
3167   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3168   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3169 }
3170 
3171 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3172                                                 DAGCombinerInfo &DCI) const {
3173   if (N->getValueType(0) != MVT::i64)
3174     return SDValue();
3175 
3176   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3177   if (!RHS)
3178     return SDValue();
3179 
3180   SelectionDAG &DAG = DCI.DAG;
3181   SDLoc SL(N);
3182   unsigned RHSVal = RHS->getZExtValue();
3183 
3184   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3185   if (RHSVal == 32) {
3186     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3187     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3188                                    DAG.getConstant(31, SL, MVT::i32));
3189 
3190     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3191     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3192   }
3193 
3194   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3195   if (RHSVal == 63) {
3196     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3197     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3198                                    DAG.getConstant(31, SL, MVT::i32));
3199     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3200     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3201   }
3202 
3203   return SDValue();
3204 }
3205 
3206 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3207                                                 DAGCombinerInfo &DCI) const {
3208   auto *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3209   if (!RHS)
3210     return SDValue();
3211 
3212   EVT VT = N->getValueType(0);
3213   SDValue LHS = N->getOperand(0);
3214   unsigned ShiftAmt = RHS->getZExtValue();
3215   SelectionDAG &DAG = DCI.DAG;
3216   SDLoc SL(N);
3217 
3218   // fold (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1)
3219   // this improves the ability to match BFE patterns in isel.
3220   if (LHS.getOpcode() == ISD::AND) {
3221     if (auto *Mask = dyn_cast<ConstantSDNode>(LHS.getOperand(1))) {
3222       if (Mask->getAPIntValue().isShiftedMask() &&
3223           Mask->getAPIntValue().countTrailingZeros() == ShiftAmt) {
3224         return DAG.getNode(
3225             ISD::AND, SL, VT,
3226             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(0), N->getOperand(1)),
3227             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(1), N->getOperand(1)));
3228       }
3229     }
3230   }
3231 
3232   if (VT != MVT::i64)
3233     return SDValue();
3234 
3235   if (ShiftAmt < 32)
3236     return SDValue();
3237 
3238   // srl i64:x, C for C >= 32
3239   // =>
3240   //   build_pair (srl hi_32(x), C - 32), 0
3241   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3242   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3243 
3244   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, LHS);
3245   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecOp, One);
3246 
3247   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3248   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3249 
3250   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3251 
3252   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3253 }
3254 
3255 SDValue AMDGPUTargetLowering::performTruncateCombine(
3256   SDNode *N, DAGCombinerInfo &DCI) const {
3257   SDLoc SL(N);
3258   SelectionDAG &DAG = DCI.DAG;
3259   EVT VT = N->getValueType(0);
3260   SDValue Src = N->getOperand(0);
3261 
3262   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3263   if (Src.getOpcode() == ISD::BITCAST && !VT.isVector()) {
3264     SDValue Vec = Src.getOperand(0);
3265     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3266       SDValue Elt0 = Vec.getOperand(0);
3267       EVT EltVT = Elt0.getValueType();
3268       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3269         if (EltVT.isFloatingPoint()) {
3270           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3271                              EltVT.changeTypeToInteger(), Elt0);
3272         }
3273 
3274         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3275       }
3276     }
3277   }
3278 
3279   // Equivalent of above for accessing the high element of a vector as an
3280   // integer operation.
3281   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3282   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3283     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3284       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3285         SDValue BV = stripBitcast(Src.getOperand(0));
3286         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3287             BV.getValueType().getVectorNumElements() == 2) {
3288           SDValue SrcElt = BV.getOperand(1);
3289           EVT SrcEltVT = SrcElt.getValueType();
3290           if (SrcEltVT.isFloatingPoint()) {
3291             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3292                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3293           }
3294 
3295           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3296         }
3297       }
3298     }
3299   }
3300 
3301   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3302   //
3303   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3304   //     i16 (trunc (srl (i32 (trunc x), K)))
3305   if (VT.getScalarSizeInBits() < 32) {
3306     EVT SrcVT = Src.getValueType();
3307     if (SrcVT.getScalarSizeInBits() > 32 &&
3308         (Src.getOpcode() == ISD::SRL ||
3309          Src.getOpcode() == ISD::SRA ||
3310          Src.getOpcode() == ISD::SHL)) {
3311       SDValue Amt = Src.getOperand(1);
3312       KnownBits Known = DAG.computeKnownBits(Amt);
3313       unsigned Size = VT.getScalarSizeInBits();
3314       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3315           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3316         EVT MidVT = VT.isVector() ?
3317           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3318                            VT.getVectorNumElements()) : MVT::i32;
3319 
3320         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3321         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3322                                     Src.getOperand(0));
3323         DCI.AddToWorklist(Trunc.getNode());
3324 
3325         if (Amt.getValueType() != NewShiftVT) {
3326           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3327           DCI.AddToWorklist(Amt.getNode());
3328         }
3329 
3330         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3331                                           Trunc, Amt);
3332         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3333       }
3334     }
3335   }
3336 
3337   return SDValue();
3338 }
3339 
3340 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3341 // instructions. If we only match on the legalized i64 mul expansion,
3342 // SimplifyDemandedBits will be unable to remove them because there will be
3343 // multiple uses due to the separate mul + mulh[su].
3344 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3345                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3346   if (Size <= 32) {
3347     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3348     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3349   }
3350 
3351   // Because we want to eliminate extension instructions before the
3352   // operation, we need to create a single user here (i.e. not the separate
3353   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3354 
3355   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3356 
3357   SDValue Mul = DAG.getNode(MulOpc, SL,
3358                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3359 
3360   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3361                      Mul.getValue(0), Mul.getValue(1));
3362 }
3363 
3364 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3365                                                 DAGCombinerInfo &DCI) const {
3366   EVT VT = N->getValueType(0);
3367 
3368   unsigned Size = VT.getSizeInBits();
3369   if (VT.isVector() || Size > 64)
3370     return SDValue();
3371 
3372   // There are i16 integer mul/mad.
3373   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3374     return SDValue();
3375 
3376   SelectionDAG &DAG = DCI.DAG;
3377   SDLoc DL(N);
3378 
3379   SDValue N0 = N->getOperand(0);
3380   SDValue N1 = N->getOperand(1);
3381 
3382   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3383   // in the source into any_extends if the result of the mul is truncated. Since
3384   // we can assume the high bits are whatever we want, use the underlying value
3385   // to avoid the unknown high bits from interfering.
3386   if (N0.getOpcode() == ISD::ANY_EXTEND)
3387     N0 = N0.getOperand(0);
3388 
3389   if (N1.getOpcode() == ISD::ANY_EXTEND)
3390     N1 = N1.getOperand(0);
3391 
3392   SDValue Mul;
3393 
3394   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3395     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3396     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3397     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3398   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3399     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3400     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3401     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3402   } else {
3403     return SDValue();
3404   }
3405 
3406   // We need to use sext even for MUL_U24, because MUL_U24 is used
3407   // for signed multiply of 8 and 16-bit types.
3408   return DAG.getSExtOrTrunc(Mul, DL, VT);
3409 }
3410 
3411 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3412                                                   DAGCombinerInfo &DCI) const {
3413   EVT VT = N->getValueType(0);
3414 
3415   if (!Subtarget->hasMulI24() || VT.isVector())
3416     return SDValue();
3417 
3418   SelectionDAG &DAG = DCI.DAG;
3419   SDLoc DL(N);
3420 
3421   SDValue N0 = N->getOperand(0);
3422   SDValue N1 = N->getOperand(1);
3423 
3424   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3425     return SDValue();
3426 
3427   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3428   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3429 
3430   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3431   DCI.AddToWorklist(Mulhi.getNode());
3432   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3433 }
3434 
3435 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3436                                                   DAGCombinerInfo &DCI) const {
3437   EVT VT = N->getValueType(0);
3438 
3439   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3440     return SDValue();
3441 
3442   SelectionDAG &DAG = DCI.DAG;
3443   SDLoc DL(N);
3444 
3445   SDValue N0 = N->getOperand(0);
3446   SDValue N1 = N->getOperand(1);
3447 
3448   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3449     return SDValue();
3450 
3451   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3452   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3453 
3454   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3455   DCI.AddToWorklist(Mulhi.getNode());
3456   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3457 }
3458 
3459 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3460   SDNode *N, DAGCombinerInfo &DCI) const {
3461   SelectionDAG &DAG = DCI.DAG;
3462 
3463   // Simplify demanded bits before splitting into multiple users.
3464   if (SDValue V = simplifyI24(N, DCI))
3465     return V;
3466 
3467   SDValue N0 = N->getOperand(0);
3468   SDValue N1 = N->getOperand(1);
3469 
3470   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3471 
3472   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3473   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3474 
3475   SDLoc SL(N);
3476 
3477   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3478   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3479   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3480 }
3481 
3482 static bool isNegativeOne(SDValue Val) {
3483   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3484     return C->isAllOnesValue();
3485   return false;
3486 }
3487 
3488 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3489                                           SDValue Op,
3490                                           const SDLoc &DL,
3491                                           unsigned Opc) const {
3492   EVT VT = Op.getValueType();
3493   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3494   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3495                               LegalVT != MVT::i16))
3496     return SDValue();
3497 
3498   if (VT != MVT::i32)
3499     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3500 
3501   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3502   if (VT != MVT::i32)
3503     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3504 
3505   return FFBX;
3506 }
3507 
3508 // The native instructions return -1 on 0 input. Optimize out a select that
3509 // produces -1 on 0.
3510 //
3511 // TODO: If zero is not undef, we could also do this if the output is compared
3512 // against the bitwidth.
3513 //
3514 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3515 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3516                                                  SDValue LHS, SDValue RHS,
3517                                                  DAGCombinerInfo &DCI) const {
3518   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3519   if (!CmpRhs || !CmpRhs->isNullValue())
3520     return SDValue();
3521 
3522   SelectionDAG &DAG = DCI.DAG;
3523   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3524   SDValue CmpLHS = Cond.getOperand(0);
3525 
3526   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3527                                            AMDGPUISD::FFBH_U32;
3528 
3529   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3530   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3531   if (CCOpcode == ISD::SETEQ &&
3532       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3533       RHS.getOperand(0) == CmpLHS &&
3534       isNegativeOne(LHS)) {
3535     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3536   }
3537 
3538   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3539   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3540   if (CCOpcode == ISD::SETNE &&
3541       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3542       LHS.getOperand(0) == CmpLHS &&
3543       isNegativeOne(RHS)) {
3544     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3545   }
3546 
3547   return SDValue();
3548 }
3549 
3550 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3551                                          unsigned Op,
3552                                          const SDLoc &SL,
3553                                          SDValue Cond,
3554                                          SDValue N1,
3555                                          SDValue N2) {
3556   SelectionDAG &DAG = DCI.DAG;
3557   EVT VT = N1.getValueType();
3558 
3559   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3560                                   N1.getOperand(0), N2.getOperand(0));
3561   DCI.AddToWorklist(NewSelect.getNode());
3562   return DAG.getNode(Op, SL, VT, NewSelect);
3563 }
3564 
3565 // Pull a free FP operation out of a select so it may fold into uses.
3566 //
3567 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3568 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3569 //
3570 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3571 // select c, (fabs x), +k -> fabs (select c, x, k)
3572 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3573                                     SDValue N) {
3574   SelectionDAG &DAG = DCI.DAG;
3575   SDValue Cond = N.getOperand(0);
3576   SDValue LHS = N.getOperand(1);
3577   SDValue RHS = N.getOperand(2);
3578 
3579   EVT VT = N.getValueType();
3580   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3581       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3582     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3583                                      SDLoc(N), Cond, LHS, RHS);
3584   }
3585 
3586   bool Inv = false;
3587   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3588     std::swap(LHS, RHS);
3589     Inv = true;
3590   }
3591 
3592   // TODO: Support vector constants.
3593   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3594   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3595     SDLoc SL(N);
3596     // If one side is an fneg/fabs and the other is a constant, we can push the
3597     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3598     SDValue NewLHS = LHS.getOperand(0);
3599     SDValue NewRHS = RHS;
3600 
3601     // Careful: if the neg can be folded up, don't try to pull it back down.
3602     bool ShouldFoldNeg = true;
3603 
3604     if (NewLHS.hasOneUse()) {
3605       unsigned Opc = NewLHS.getOpcode();
3606       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3607         ShouldFoldNeg = false;
3608       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3609         ShouldFoldNeg = false;
3610     }
3611 
3612     if (ShouldFoldNeg) {
3613       if (LHS.getOpcode() == ISD::FNEG)
3614         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3615       else if (CRHS->isNegative())
3616         return SDValue();
3617 
3618       if (Inv)
3619         std::swap(NewLHS, NewRHS);
3620 
3621       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3622                                       Cond, NewLHS, NewRHS);
3623       DCI.AddToWorklist(NewSelect.getNode());
3624       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3625     }
3626   }
3627 
3628   return SDValue();
3629 }
3630 
3631 
3632 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3633                                                    DAGCombinerInfo &DCI) const {
3634   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3635     return Folded;
3636 
3637   SDValue Cond = N->getOperand(0);
3638   if (Cond.getOpcode() != ISD::SETCC)
3639     return SDValue();
3640 
3641   EVT VT = N->getValueType(0);
3642   SDValue LHS = Cond.getOperand(0);
3643   SDValue RHS = Cond.getOperand(1);
3644   SDValue CC = Cond.getOperand(2);
3645 
3646   SDValue True = N->getOperand(1);
3647   SDValue False = N->getOperand(2);
3648 
3649   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3650     SelectionDAG &DAG = DCI.DAG;
3651     if (DAG.isConstantValueOfAnyType(True) &&
3652         !DAG.isConstantValueOfAnyType(False)) {
3653       // Swap cmp + select pair to move constant to false input.
3654       // This will allow using VOPC cndmasks more often.
3655       // select (setcc x, y), k, x -> select (setccinv x, y), x, k
3656 
3657       SDLoc SL(N);
3658       ISD::CondCode NewCC =
3659           getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), LHS.getValueType());
3660 
3661       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3662       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3663     }
3664 
3665     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3666       SDValue MinMax
3667         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3668       // Revisit this node so we can catch min3/max3/med3 patterns.
3669       //DCI.AddToWorklist(MinMax.getNode());
3670       return MinMax;
3671     }
3672   }
3673 
3674   // There's no reason to not do this if the condition has other uses.
3675   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3676 }
3677 
3678 static bool isInv2Pi(const APFloat &APF) {
3679   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3680   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3681   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3682 
3683   return APF.bitwiseIsEqual(KF16) ||
3684          APF.bitwiseIsEqual(KF32) ||
3685          APF.bitwiseIsEqual(KF64);
3686 }
3687 
3688 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3689 // additional cost to negate them.
3690 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3691   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3692     if (C->isZero() && !C->isNegative())
3693       return true;
3694 
3695     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3696       return true;
3697   }
3698 
3699   return false;
3700 }
3701 
3702 static unsigned inverseMinMax(unsigned Opc) {
3703   switch (Opc) {
3704   case ISD::FMAXNUM:
3705     return ISD::FMINNUM;
3706   case ISD::FMINNUM:
3707     return ISD::FMAXNUM;
3708   case ISD::FMAXNUM_IEEE:
3709     return ISD::FMINNUM_IEEE;
3710   case ISD::FMINNUM_IEEE:
3711     return ISD::FMAXNUM_IEEE;
3712   case AMDGPUISD::FMAX_LEGACY:
3713     return AMDGPUISD::FMIN_LEGACY;
3714   case AMDGPUISD::FMIN_LEGACY:
3715     return  AMDGPUISD::FMAX_LEGACY;
3716   default:
3717     llvm_unreachable("invalid min/max opcode");
3718   }
3719 }
3720 
3721 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3722                                                  DAGCombinerInfo &DCI) const {
3723   SelectionDAG &DAG = DCI.DAG;
3724   SDValue N0 = N->getOperand(0);
3725   EVT VT = N->getValueType(0);
3726 
3727   unsigned Opc = N0.getOpcode();
3728 
3729   // If the input has multiple uses and we can either fold the negate down, or
3730   // the other uses cannot, give up. This both prevents unprofitable
3731   // transformations and infinite loops: we won't repeatedly try to fold around
3732   // a negate that has no 'good' form.
3733   if (N0.hasOneUse()) {
3734     // This may be able to fold into the source, but at a code size cost. Don't
3735     // fold if the fold into the user is free.
3736     if (allUsesHaveSourceMods(N, 0))
3737       return SDValue();
3738   } else {
3739     if (fnegFoldsIntoOp(Opc) &&
3740         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3741       return SDValue();
3742   }
3743 
3744   SDLoc SL(N);
3745   switch (Opc) {
3746   case ISD::FADD: {
3747     if (!mayIgnoreSignedZero(N0))
3748       return SDValue();
3749 
3750     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3751     SDValue LHS = N0.getOperand(0);
3752     SDValue RHS = N0.getOperand(1);
3753 
3754     if (LHS.getOpcode() != ISD::FNEG)
3755       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3756     else
3757       LHS = LHS.getOperand(0);
3758 
3759     if (RHS.getOpcode() != ISD::FNEG)
3760       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3761     else
3762       RHS = RHS.getOperand(0);
3763 
3764     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3765     if (Res.getOpcode() != ISD::FADD)
3766       return SDValue(); // Op got folded away.
3767     if (!N0.hasOneUse())
3768       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3769     return Res;
3770   }
3771   case ISD::FMUL:
3772   case AMDGPUISD::FMUL_LEGACY: {
3773     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3774     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3775     SDValue LHS = N0.getOperand(0);
3776     SDValue RHS = N0.getOperand(1);
3777 
3778     if (LHS.getOpcode() == ISD::FNEG)
3779       LHS = LHS.getOperand(0);
3780     else if (RHS.getOpcode() == ISD::FNEG)
3781       RHS = RHS.getOperand(0);
3782     else
3783       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3784 
3785     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3786     if (Res.getOpcode() != Opc)
3787       return SDValue(); // Op got folded away.
3788     if (!N0.hasOneUse())
3789       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3790     return Res;
3791   }
3792   case ISD::FMA:
3793   case ISD::FMAD: {
3794     if (!mayIgnoreSignedZero(N0))
3795       return SDValue();
3796 
3797     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3798     SDValue LHS = N0.getOperand(0);
3799     SDValue MHS = N0.getOperand(1);
3800     SDValue RHS = N0.getOperand(2);
3801 
3802     if (LHS.getOpcode() == ISD::FNEG)
3803       LHS = LHS.getOperand(0);
3804     else if (MHS.getOpcode() == ISD::FNEG)
3805       MHS = MHS.getOperand(0);
3806     else
3807       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3808 
3809     if (RHS.getOpcode() != ISD::FNEG)
3810       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3811     else
3812       RHS = RHS.getOperand(0);
3813 
3814     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3815     if (Res.getOpcode() != Opc)
3816       return SDValue(); // Op got folded away.
3817     if (!N0.hasOneUse())
3818       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3819     return Res;
3820   }
3821   case ISD::FMAXNUM:
3822   case ISD::FMINNUM:
3823   case ISD::FMAXNUM_IEEE:
3824   case ISD::FMINNUM_IEEE:
3825   case AMDGPUISD::FMAX_LEGACY:
3826   case AMDGPUISD::FMIN_LEGACY: {
3827     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3828     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3829     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3830     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3831 
3832     SDValue LHS = N0.getOperand(0);
3833     SDValue RHS = N0.getOperand(1);
3834 
3835     // 0 doesn't have a negated inline immediate.
3836     // TODO: This constant check should be generalized to other operations.
3837     if (isConstantCostlierToNegate(RHS))
3838       return SDValue();
3839 
3840     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3841     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3842     unsigned Opposite = inverseMinMax(Opc);
3843 
3844     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3845     if (Res.getOpcode() != Opposite)
3846       return SDValue(); // Op got folded away.
3847     if (!N0.hasOneUse())
3848       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3849     return Res;
3850   }
3851   case AMDGPUISD::FMED3: {
3852     SDValue Ops[3];
3853     for (unsigned I = 0; I < 3; ++I)
3854       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3855 
3856     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3857     if (Res.getOpcode() != AMDGPUISD::FMED3)
3858       return SDValue(); // Op got folded away.
3859     if (!N0.hasOneUse())
3860       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3861     return Res;
3862   }
3863   case ISD::FP_EXTEND:
3864   case ISD::FTRUNC:
3865   case ISD::FRINT:
3866   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3867   case ISD::FSIN:
3868   case ISD::FCANONICALIZE:
3869   case AMDGPUISD::RCP:
3870   case AMDGPUISD::RCP_LEGACY:
3871   case AMDGPUISD::RCP_IFLAG:
3872   case AMDGPUISD::SIN_HW: {
3873     SDValue CvtSrc = N0.getOperand(0);
3874     if (CvtSrc.getOpcode() == ISD::FNEG) {
3875       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3876       // (fneg (rcp (fneg x))) -> (rcp x)
3877       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3878     }
3879 
3880     if (!N0.hasOneUse())
3881       return SDValue();
3882 
3883     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3884     // (fneg (rcp x)) -> (rcp (fneg x))
3885     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3886     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3887   }
3888   case ISD::FP_ROUND: {
3889     SDValue CvtSrc = N0.getOperand(0);
3890 
3891     if (CvtSrc.getOpcode() == ISD::FNEG) {
3892       // (fneg (fp_round (fneg x))) -> (fp_round x)
3893       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3894                          CvtSrc.getOperand(0), N0.getOperand(1));
3895     }
3896 
3897     if (!N0.hasOneUse())
3898       return SDValue();
3899 
3900     // (fneg (fp_round x)) -> (fp_round (fneg x))
3901     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3902     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3903   }
3904   case ISD::FP16_TO_FP: {
3905     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3906     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3907     // Put the fneg back as a legal source operation that can be matched later.
3908     SDLoc SL(N);
3909 
3910     SDValue Src = N0.getOperand(0);
3911     EVT SrcVT = Src.getValueType();
3912 
3913     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3914     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3915                                   DAG.getConstant(0x8000, SL, SrcVT));
3916     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3917   }
3918   default:
3919     return SDValue();
3920   }
3921 }
3922 
3923 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3924                                                  DAGCombinerInfo &DCI) const {
3925   SelectionDAG &DAG = DCI.DAG;
3926   SDValue N0 = N->getOperand(0);
3927 
3928   if (!N0.hasOneUse())
3929     return SDValue();
3930 
3931   switch (N0.getOpcode()) {
3932   case ISD::FP16_TO_FP: {
3933     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3934     SDLoc SL(N);
3935     SDValue Src = N0.getOperand(0);
3936     EVT SrcVT = Src.getValueType();
3937 
3938     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3939     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3940                                   DAG.getConstant(0x7fff, SL, SrcVT));
3941     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3942   }
3943   default:
3944     return SDValue();
3945   }
3946 }
3947 
3948 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3949                                                 DAGCombinerInfo &DCI) const {
3950   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3951   if (!CFP)
3952     return SDValue();
3953 
3954   // XXX - Should this flush denormals?
3955   const APFloat &Val = CFP->getValueAPF();
3956   APFloat One(Val.getSemantics(), "1.0");
3957   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3958 }
3959 
3960 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3961                                                 DAGCombinerInfo &DCI) const {
3962   SelectionDAG &DAG = DCI.DAG;
3963   SDLoc DL(N);
3964 
3965   switch(N->getOpcode()) {
3966   default:
3967     break;
3968   case ISD::BITCAST: {
3969     EVT DestVT = N->getValueType(0);
3970 
3971     // Push casts through vector builds. This helps avoid emitting a large
3972     // number of copies when materializing floating point vector constants.
3973     //
3974     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3975     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3976     if (DestVT.isVector()) {
3977       SDValue Src = N->getOperand(0);
3978       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3979         EVT SrcVT = Src.getValueType();
3980         unsigned NElts = DestVT.getVectorNumElements();
3981 
3982         if (SrcVT.getVectorNumElements() == NElts) {
3983           EVT DestEltVT = DestVT.getVectorElementType();
3984 
3985           SmallVector<SDValue, 8> CastedElts;
3986           SDLoc SL(N);
3987           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3988             SDValue Elt = Src.getOperand(I);
3989             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3990           }
3991 
3992           return DAG.getBuildVector(DestVT, SL, CastedElts);
3993         }
3994       }
3995     }
3996 
3997     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3998       break;
3999 
4000     // Fold bitcasts of constants.
4001     //
4002     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
4003     // TODO: Generalize and move to DAGCombiner
4004     SDValue Src = N->getOperand(0);
4005     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
4006       if (Src.getValueType() == MVT::i64) {
4007         SDLoc SL(N);
4008         uint64_t CVal = C->getZExtValue();
4009         SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
4010                                  DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
4011                                  DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
4012         return DAG.getNode(ISD::BITCAST, SL, DestVT, BV);
4013       }
4014     }
4015 
4016     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
4017       const APInt &Val = C->getValueAPF().bitcastToAPInt();
4018       SDLoc SL(N);
4019       uint64_t CVal = Val.getZExtValue();
4020       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
4021                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
4022                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
4023 
4024       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
4025     }
4026 
4027     break;
4028   }
4029   case ISD::SHL: {
4030     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4031       break;
4032 
4033     return performShlCombine(N, DCI);
4034   }
4035   case ISD::SRL: {
4036     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4037       break;
4038 
4039     return performSrlCombine(N, DCI);
4040   }
4041   case ISD::SRA: {
4042     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4043       break;
4044 
4045     return performSraCombine(N, DCI);
4046   }
4047   case ISD::TRUNCATE:
4048     return performTruncateCombine(N, DCI);
4049   case ISD::MUL:
4050     return performMulCombine(N, DCI);
4051   case ISD::MULHS:
4052     return performMulhsCombine(N, DCI);
4053   case ISD::MULHU:
4054     return performMulhuCombine(N, DCI);
4055   case AMDGPUISD::MUL_I24:
4056   case AMDGPUISD::MUL_U24:
4057   case AMDGPUISD::MULHI_I24:
4058   case AMDGPUISD::MULHI_U24: {
4059     if (SDValue V = simplifyI24(N, DCI))
4060       return V;
4061     return SDValue();
4062   }
4063   case AMDGPUISD::MUL_LOHI_I24:
4064   case AMDGPUISD::MUL_LOHI_U24:
4065     return performMulLoHi24Combine(N, DCI);
4066   case ISD::SELECT:
4067     return performSelectCombine(N, DCI);
4068   case ISD::FNEG:
4069     return performFNegCombine(N, DCI);
4070   case ISD::FABS:
4071     return performFAbsCombine(N, DCI);
4072   case AMDGPUISD::BFE_I32:
4073   case AMDGPUISD::BFE_U32: {
4074     assert(!N->getValueType(0).isVector() &&
4075            "Vector handling of BFE not implemented");
4076     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
4077     if (!Width)
4078       break;
4079 
4080     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
4081     if (WidthVal == 0)
4082       return DAG.getConstant(0, DL, MVT::i32);
4083 
4084     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
4085     if (!Offset)
4086       break;
4087 
4088     SDValue BitsFrom = N->getOperand(0);
4089     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
4090 
4091     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
4092 
4093     if (OffsetVal == 0) {
4094       // This is already sign / zero extended, so try to fold away extra BFEs.
4095       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
4096 
4097       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
4098       if (OpSignBits >= SignBits)
4099         return BitsFrom;
4100 
4101       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
4102       if (Signed) {
4103         // This is a sign_extend_inreg. Replace it to take advantage of existing
4104         // DAG Combines. If not eliminated, we will match back to BFE during
4105         // selection.
4106 
4107         // TODO: The sext_inreg of extended types ends, although we can could
4108         // handle them in a single BFE.
4109         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
4110                            DAG.getValueType(SmallVT));
4111       }
4112 
4113       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
4114     }
4115 
4116     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
4117       if (Signed) {
4118         return constantFoldBFE<int32_t>(DAG,
4119                                         CVal->getSExtValue(),
4120                                         OffsetVal,
4121                                         WidthVal,
4122                                         DL);
4123       }
4124 
4125       return constantFoldBFE<uint32_t>(DAG,
4126                                        CVal->getZExtValue(),
4127                                        OffsetVal,
4128                                        WidthVal,
4129                                        DL);
4130     }
4131 
4132     if ((OffsetVal + WidthVal) >= 32 &&
4133         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
4134       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
4135       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
4136                          BitsFrom, ShiftVal);
4137     }
4138 
4139     if (BitsFrom.hasOneUse()) {
4140       APInt Demanded = APInt::getBitsSet(32,
4141                                          OffsetVal,
4142                                          OffsetVal + WidthVal);
4143 
4144       KnownBits Known;
4145       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
4146                                             !DCI.isBeforeLegalizeOps());
4147       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
4148       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
4149           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
4150         DCI.CommitTargetLoweringOpt(TLO);
4151       }
4152     }
4153 
4154     break;
4155   }
4156   case ISD::LOAD:
4157     return performLoadCombine(N, DCI);
4158   case ISD::STORE:
4159     return performStoreCombine(N, DCI);
4160   case AMDGPUISD::RCP:
4161   case AMDGPUISD::RCP_IFLAG:
4162     return performRcpCombine(N, DCI);
4163   case ISD::AssertZext:
4164   case ISD::AssertSext:
4165     return performAssertSZExtCombine(N, DCI);
4166   case ISD::INTRINSIC_WO_CHAIN:
4167     return performIntrinsicWOChainCombine(N, DCI);
4168   }
4169   return SDValue();
4170 }
4171 
4172 //===----------------------------------------------------------------------===//
4173 // Helper functions
4174 //===----------------------------------------------------------------------===//
4175 
4176 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
4177                                                    const TargetRegisterClass *RC,
4178                                                    Register Reg, EVT VT,
4179                                                    const SDLoc &SL,
4180                                                    bool RawReg) const {
4181   MachineFunction &MF = DAG.getMachineFunction();
4182   MachineRegisterInfo &MRI = MF.getRegInfo();
4183   Register VReg;
4184 
4185   if (!MRI.isLiveIn(Reg)) {
4186     VReg = MRI.createVirtualRegister(RC);
4187     MRI.addLiveIn(Reg, VReg);
4188   } else {
4189     VReg = MRI.getLiveInVirtReg(Reg);
4190   }
4191 
4192   if (RawReg)
4193     return DAG.getRegister(VReg, VT);
4194 
4195   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
4196 }
4197 
4198 // This may be called multiple times, and nothing prevents creating multiple
4199 // objects at the same offset. See if we already defined this object.
4200 static int getOrCreateFixedStackObject(MachineFrameInfo &MFI, unsigned Size,
4201                                        int64_t Offset) {
4202   for (int I = MFI.getObjectIndexBegin(); I < 0; ++I) {
4203     if (MFI.getObjectOffset(I) == Offset) {
4204       assert(MFI.getObjectSize(I) == Size);
4205       return I;
4206     }
4207   }
4208 
4209   return MFI.CreateFixedObject(Size, Offset, true);
4210 }
4211 
4212 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
4213                                                   EVT VT,
4214                                                   const SDLoc &SL,
4215                                                   int64_t Offset) const {
4216   MachineFunction &MF = DAG.getMachineFunction();
4217   MachineFrameInfo &MFI = MF.getFrameInfo();
4218   int FI = getOrCreateFixedStackObject(MFI, VT.getStoreSize(), Offset);
4219 
4220   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4221   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4222 
4223   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4224                      MachineMemOperand::MODereferenceable |
4225                      MachineMemOperand::MOInvariant);
4226 }
4227 
4228 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4229                                                    const SDLoc &SL,
4230                                                    SDValue Chain,
4231                                                    SDValue ArgVal,
4232                                                    int64_t Offset) const {
4233   MachineFunction &MF = DAG.getMachineFunction();
4234   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4235 
4236   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4237   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4238                                MachineMemOperand::MODereferenceable);
4239   return Store;
4240 }
4241 
4242 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4243                                              const TargetRegisterClass *RC,
4244                                              EVT VT, const SDLoc &SL,
4245                                              const ArgDescriptor &Arg) const {
4246   assert(Arg && "Attempting to load missing argument");
4247 
4248   SDValue V = Arg.isRegister() ?
4249     CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL) :
4250     loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4251 
4252   if (!Arg.isMasked())
4253     return V;
4254 
4255   unsigned Mask = Arg.getMask();
4256   unsigned Shift = countTrailingZeros<unsigned>(Mask);
4257   V = DAG.getNode(ISD::SRL, SL, VT, V,
4258                   DAG.getShiftAmountConstant(Shift, VT, SL));
4259   return DAG.getNode(ISD::AND, SL, VT, V,
4260                      DAG.getConstant(Mask >> Shift, SL, VT));
4261 }
4262 
4263 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4264     const MachineFunction &MF, const ImplicitParameter Param) const {
4265   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4266   const AMDGPUSubtarget &ST =
4267       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4268   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4269   const Align Alignment = ST.getAlignmentForImplicitArgPtr();
4270   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4271                        ExplicitArgOffset;
4272   switch (Param) {
4273   case GRID_DIM:
4274     return ArgOffset;
4275   case GRID_OFFSET:
4276     return ArgOffset + 4;
4277   }
4278   llvm_unreachable("unexpected implicit parameter type");
4279 }
4280 
4281 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4282 
4283 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4284   switch ((AMDGPUISD::NodeType)Opcode) {
4285   case AMDGPUISD::FIRST_NUMBER: break;
4286   // AMDIL DAG nodes
4287   NODE_NAME_CASE(UMUL);
4288   NODE_NAME_CASE(BRANCH_COND);
4289 
4290   // AMDGPU DAG nodes
4291   NODE_NAME_CASE(IF)
4292   NODE_NAME_CASE(ELSE)
4293   NODE_NAME_CASE(LOOP)
4294   NODE_NAME_CASE(CALL)
4295   NODE_NAME_CASE(TC_RETURN)
4296   NODE_NAME_CASE(TRAP)
4297   NODE_NAME_CASE(RET_FLAG)
4298   NODE_NAME_CASE(RETURN_TO_EPILOG)
4299   NODE_NAME_CASE(ENDPGM)
4300   NODE_NAME_CASE(DWORDADDR)
4301   NODE_NAME_CASE(FRACT)
4302   NODE_NAME_CASE(SETCC)
4303   NODE_NAME_CASE(SETREG)
4304   NODE_NAME_CASE(DENORM_MODE)
4305   NODE_NAME_CASE(FMA_W_CHAIN)
4306   NODE_NAME_CASE(FMUL_W_CHAIN)
4307   NODE_NAME_CASE(CLAMP)
4308   NODE_NAME_CASE(COS_HW)
4309   NODE_NAME_CASE(SIN_HW)
4310   NODE_NAME_CASE(FMAX_LEGACY)
4311   NODE_NAME_CASE(FMIN_LEGACY)
4312   NODE_NAME_CASE(FMAX3)
4313   NODE_NAME_CASE(SMAX3)
4314   NODE_NAME_CASE(UMAX3)
4315   NODE_NAME_CASE(FMIN3)
4316   NODE_NAME_CASE(SMIN3)
4317   NODE_NAME_CASE(UMIN3)
4318   NODE_NAME_CASE(FMED3)
4319   NODE_NAME_CASE(SMED3)
4320   NODE_NAME_CASE(UMED3)
4321   NODE_NAME_CASE(FDOT2)
4322   NODE_NAME_CASE(URECIP)
4323   NODE_NAME_CASE(DIV_SCALE)
4324   NODE_NAME_CASE(DIV_FMAS)
4325   NODE_NAME_CASE(DIV_FIXUP)
4326   NODE_NAME_CASE(FMAD_FTZ)
4327   NODE_NAME_CASE(RCP)
4328   NODE_NAME_CASE(RSQ)
4329   NODE_NAME_CASE(RCP_LEGACY)
4330   NODE_NAME_CASE(RCP_IFLAG)
4331   NODE_NAME_CASE(FMUL_LEGACY)
4332   NODE_NAME_CASE(RSQ_CLAMP)
4333   NODE_NAME_CASE(LDEXP)
4334   NODE_NAME_CASE(FP_CLASS)
4335   NODE_NAME_CASE(DOT4)
4336   NODE_NAME_CASE(CARRY)
4337   NODE_NAME_CASE(BORROW)
4338   NODE_NAME_CASE(BFE_U32)
4339   NODE_NAME_CASE(BFE_I32)
4340   NODE_NAME_CASE(BFI)
4341   NODE_NAME_CASE(BFM)
4342   NODE_NAME_CASE(FFBH_U32)
4343   NODE_NAME_CASE(FFBH_I32)
4344   NODE_NAME_CASE(FFBL_B32)
4345   NODE_NAME_CASE(MUL_U24)
4346   NODE_NAME_CASE(MUL_I24)
4347   NODE_NAME_CASE(MULHI_U24)
4348   NODE_NAME_CASE(MULHI_I24)
4349   NODE_NAME_CASE(MUL_LOHI_U24)
4350   NODE_NAME_CASE(MUL_LOHI_I24)
4351   NODE_NAME_CASE(MAD_U24)
4352   NODE_NAME_CASE(MAD_I24)
4353   NODE_NAME_CASE(MAD_I64_I32)
4354   NODE_NAME_CASE(MAD_U64_U32)
4355   NODE_NAME_CASE(PERM)
4356   NODE_NAME_CASE(TEXTURE_FETCH)
4357   NODE_NAME_CASE(R600_EXPORT)
4358   NODE_NAME_CASE(CONST_ADDRESS)
4359   NODE_NAME_CASE(REGISTER_LOAD)
4360   NODE_NAME_CASE(REGISTER_STORE)
4361   NODE_NAME_CASE(SAMPLE)
4362   NODE_NAME_CASE(SAMPLEB)
4363   NODE_NAME_CASE(SAMPLED)
4364   NODE_NAME_CASE(SAMPLEL)
4365   NODE_NAME_CASE(CVT_F32_UBYTE0)
4366   NODE_NAME_CASE(CVT_F32_UBYTE1)
4367   NODE_NAME_CASE(CVT_F32_UBYTE2)
4368   NODE_NAME_CASE(CVT_F32_UBYTE3)
4369   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4370   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4371   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4372   NODE_NAME_CASE(CVT_PK_I16_I32)
4373   NODE_NAME_CASE(CVT_PK_U16_U32)
4374   NODE_NAME_CASE(FP_TO_FP16)
4375   NODE_NAME_CASE(FP16_ZEXT)
4376   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4377   NODE_NAME_CASE(CONST_DATA_PTR)
4378   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4379   NODE_NAME_CASE(LDS)
4380   NODE_NAME_CASE(DUMMY_CHAIN)
4381   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4382   NODE_NAME_CASE(LOAD_D16_HI)
4383   NODE_NAME_CASE(LOAD_D16_LO)
4384   NODE_NAME_CASE(LOAD_D16_HI_I8)
4385   NODE_NAME_CASE(LOAD_D16_HI_U8)
4386   NODE_NAME_CASE(LOAD_D16_LO_I8)
4387   NODE_NAME_CASE(LOAD_D16_LO_U8)
4388   NODE_NAME_CASE(STORE_MSKOR)
4389   NODE_NAME_CASE(LOAD_CONSTANT)
4390   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4391   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4392   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4393   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4394   NODE_NAME_CASE(DS_ORDERED_COUNT)
4395   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4396   NODE_NAME_CASE(ATOMIC_INC)
4397   NODE_NAME_CASE(ATOMIC_DEC)
4398   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4399   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4400   NODE_NAME_CASE(ATOMIC_LOAD_CSUB)
4401   NODE_NAME_CASE(BUFFER_LOAD)
4402   NODE_NAME_CASE(BUFFER_LOAD_UBYTE)
4403   NODE_NAME_CASE(BUFFER_LOAD_USHORT)
4404   NODE_NAME_CASE(BUFFER_LOAD_BYTE)
4405   NODE_NAME_CASE(BUFFER_LOAD_SHORT)
4406   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4407   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4408   NODE_NAME_CASE(SBUFFER_LOAD)
4409   NODE_NAME_CASE(BUFFER_STORE)
4410   NODE_NAME_CASE(BUFFER_STORE_BYTE)
4411   NODE_NAME_CASE(BUFFER_STORE_SHORT)
4412   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4413   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4414   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4415   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4416   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4417   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4418   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4419   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4420   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4421   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4422   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4423   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4424   NODE_NAME_CASE(BUFFER_ATOMIC_INC)
4425   NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
4426   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4427   NODE_NAME_CASE(BUFFER_ATOMIC_CSUB)
4428   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
4429   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)
4430   NODE_NAME_CASE(ATOMIC_PK_FADD)
4431 
4432   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4433   }
4434   return nullptr;
4435 }
4436 
4437 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4438                                               SelectionDAG &DAG, int Enabled,
4439                                               int &RefinementSteps,
4440                                               bool &UseOneConstNR,
4441                                               bool Reciprocal) const {
4442   EVT VT = Operand.getValueType();
4443 
4444   if (VT == MVT::f32) {
4445     RefinementSteps = 0;
4446     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4447   }
4448 
4449   // TODO: There is also f64 rsq instruction, but the documentation is less
4450   // clear on its precision.
4451 
4452   return SDValue();
4453 }
4454 
4455 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4456                                                SelectionDAG &DAG, int Enabled,
4457                                                int &RefinementSteps) const {
4458   EVT VT = Operand.getValueType();
4459 
4460   if (VT == MVT::f32) {
4461     // Reciprocal, < 1 ulp error.
4462     //
4463     // This reciprocal approximation converges to < 0.5 ulp error with one
4464     // newton rhapson performed with two fused multiple adds (FMAs).
4465 
4466     RefinementSteps = 0;
4467     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4468   }
4469 
4470   // TODO: There is also f64 rcp instruction, but the documentation is less
4471   // clear on its precision.
4472 
4473   return SDValue();
4474 }
4475 
4476 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4477     const SDValue Op, KnownBits &Known,
4478     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4479 
4480   Known.resetAll(); // Don't know anything.
4481 
4482   unsigned Opc = Op.getOpcode();
4483 
4484   switch (Opc) {
4485   default:
4486     break;
4487   case AMDGPUISD::CARRY:
4488   case AMDGPUISD::BORROW: {
4489     Known.Zero = APInt::getHighBitsSet(32, 31);
4490     break;
4491   }
4492 
4493   case AMDGPUISD::BFE_I32:
4494   case AMDGPUISD::BFE_U32: {
4495     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4496     if (!CWidth)
4497       return;
4498 
4499     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4500 
4501     if (Opc == AMDGPUISD::BFE_U32)
4502       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4503 
4504     break;
4505   }
4506   case AMDGPUISD::FP_TO_FP16:
4507   case AMDGPUISD::FP16_ZEXT: {
4508     unsigned BitWidth = Known.getBitWidth();
4509 
4510     // High bits are zero.
4511     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4512     break;
4513   }
4514   case AMDGPUISD::MUL_U24:
4515   case AMDGPUISD::MUL_I24: {
4516     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4517     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4518     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4519                       RHSKnown.countMinTrailingZeros();
4520     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4521     // Skip extra check if all bits are known zeros.
4522     if (TrailZ >= 32)
4523       break;
4524 
4525     // Truncate to 24 bits.
4526     LHSKnown = LHSKnown.trunc(24);
4527     RHSKnown = RHSKnown.trunc(24);
4528 
4529     if (Opc == AMDGPUISD::MUL_I24) {
4530       unsigned LHSValBits = 24 - LHSKnown.countMinSignBits();
4531       unsigned RHSValBits = 24 - RHSKnown.countMinSignBits();
4532       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4533       if (MaxValBits >= 32)
4534         break;
4535       bool LHSNegative = LHSKnown.isNegative();
4536       bool LHSNonNegative = LHSKnown.isNonNegative();
4537       bool LHSPositive = LHSKnown.isStrictlyPositive();
4538       bool RHSNegative = RHSKnown.isNegative();
4539       bool RHSNonNegative = RHSKnown.isNonNegative();
4540       bool RHSPositive = RHSKnown.isStrictlyPositive();
4541 
4542       if ((LHSNonNegative && RHSNonNegative) || (LHSNegative && RHSNegative))
4543         Known.Zero.setHighBits(32 - MaxValBits);
4544       else if ((LHSNegative && RHSPositive) || (LHSPositive && RHSNegative))
4545         Known.One.setHighBits(32 - MaxValBits);
4546     } else {
4547       unsigned LHSValBits = 24 - LHSKnown.countMinLeadingZeros();
4548       unsigned RHSValBits = 24 - RHSKnown.countMinLeadingZeros();
4549       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4550       if (MaxValBits >= 32)
4551         break;
4552       Known.Zero.setHighBits(32 - MaxValBits);
4553     }
4554     break;
4555   }
4556   case AMDGPUISD::PERM: {
4557     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4558     if (!CMask)
4559       return;
4560 
4561     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4562     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4563     unsigned Sel = CMask->getZExtValue();
4564 
4565     for (unsigned I = 0; I < 32; I += 8) {
4566       unsigned SelBits = Sel & 0xff;
4567       if (SelBits < 4) {
4568         SelBits *= 8;
4569         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4570         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4571       } else if (SelBits < 7) {
4572         SelBits = (SelBits & 3) * 8;
4573         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4574         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4575       } else if (SelBits == 0x0c) {
4576         Known.Zero |= 0xFFull << I;
4577       } else if (SelBits > 0x0c) {
4578         Known.One |= 0xFFull << I;
4579       }
4580       Sel >>= 8;
4581     }
4582     break;
4583   }
4584   case AMDGPUISD::BUFFER_LOAD_UBYTE:  {
4585     Known.Zero.setHighBits(24);
4586     break;
4587   }
4588   case AMDGPUISD::BUFFER_LOAD_USHORT: {
4589     Known.Zero.setHighBits(16);
4590     break;
4591   }
4592   case AMDGPUISD::LDS: {
4593     auto GA = cast<GlobalAddressSDNode>(Op.getOperand(0).getNode());
4594     Align Alignment = GA->getGlobal()->getPointerAlignment(DAG.getDataLayout());
4595 
4596     Known.Zero.setHighBits(16);
4597     Known.Zero.setLowBits(Log2(Alignment));
4598     break;
4599   }
4600   case ISD::INTRINSIC_WO_CHAIN: {
4601     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4602     switch (IID) {
4603     case Intrinsic::amdgcn_mbcnt_lo:
4604     case Intrinsic::amdgcn_mbcnt_hi: {
4605       const GCNSubtarget &ST =
4606           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4607       // These return at most the wavefront size - 1.
4608       unsigned Size = Op.getValueType().getSizeInBits();
4609       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4610       break;
4611     }
4612     default:
4613       break;
4614     }
4615   }
4616   }
4617 }
4618 
4619 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4620     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4621     unsigned Depth) const {
4622   switch (Op.getOpcode()) {
4623   case AMDGPUISD::BFE_I32: {
4624     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4625     if (!Width)
4626       return 1;
4627 
4628     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4629     if (!isNullConstant(Op.getOperand(1)))
4630       return SignBits;
4631 
4632     // TODO: Could probably figure something out with non-0 offsets.
4633     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4634     return std::max(SignBits, Op0SignBits);
4635   }
4636 
4637   case AMDGPUISD::BFE_U32: {
4638     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4639     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4640   }
4641 
4642   case AMDGPUISD::CARRY:
4643   case AMDGPUISD::BORROW:
4644     return 31;
4645   case AMDGPUISD::BUFFER_LOAD_BYTE:
4646     return 25;
4647   case AMDGPUISD::BUFFER_LOAD_SHORT:
4648     return 17;
4649   case AMDGPUISD::BUFFER_LOAD_UBYTE:
4650     return 24;
4651   case AMDGPUISD::BUFFER_LOAD_USHORT:
4652     return 16;
4653   case AMDGPUISD::FP_TO_FP16:
4654   case AMDGPUISD::FP16_ZEXT:
4655     return 16;
4656   default:
4657     return 1;
4658   }
4659 }
4660 
4661 unsigned AMDGPUTargetLowering::computeNumSignBitsForTargetInstr(
4662   GISelKnownBits &Analysis, Register R,
4663   const APInt &DemandedElts, const MachineRegisterInfo &MRI,
4664   unsigned Depth) const {
4665   const MachineInstr *MI = MRI.getVRegDef(R);
4666   if (!MI)
4667     return 1;
4668 
4669   // TODO: Check range metadata on MMO.
4670   switch (MI->getOpcode()) {
4671   case AMDGPU::G_AMDGPU_BUFFER_LOAD_SBYTE:
4672     return 25;
4673   case AMDGPU::G_AMDGPU_BUFFER_LOAD_SSHORT:
4674     return 17;
4675   case AMDGPU::G_AMDGPU_BUFFER_LOAD_UBYTE:
4676     return 24;
4677   case AMDGPU::G_AMDGPU_BUFFER_LOAD_USHORT:
4678     return 16;
4679   default:
4680     return 1;
4681   }
4682 }
4683 
4684 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4685                                                         const SelectionDAG &DAG,
4686                                                         bool SNaN,
4687                                                         unsigned Depth) const {
4688   unsigned Opcode = Op.getOpcode();
4689   switch (Opcode) {
4690   case AMDGPUISD::FMIN_LEGACY:
4691   case AMDGPUISD::FMAX_LEGACY: {
4692     if (SNaN)
4693       return true;
4694 
4695     // TODO: Can check no nans on one of the operands for each one, but which
4696     // one?
4697     return false;
4698   }
4699   case AMDGPUISD::FMUL_LEGACY:
4700   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4701     if (SNaN)
4702       return true;
4703     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4704            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4705   }
4706   case AMDGPUISD::FMED3:
4707   case AMDGPUISD::FMIN3:
4708   case AMDGPUISD::FMAX3:
4709   case AMDGPUISD::FMAD_FTZ: {
4710     if (SNaN)
4711       return true;
4712     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4713            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4714            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4715   }
4716   case AMDGPUISD::CVT_F32_UBYTE0:
4717   case AMDGPUISD::CVT_F32_UBYTE1:
4718   case AMDGPUISD::CVT_F32_UBYTE2:
4719   case AMDGPUISD::CVT_F32_UBYTE3:
4720     return true;
4721 
4722   case AMDGPUISD::RCP:
4723   case AMDGPUISD::RSQ:
4724   case AMDGPUISD::RCP_LEGACY:
4725   case AMDGPUISD::RSQ_CLAMP: {
4726     if (SNaN)
4727       return true;
4728 
4729     // TODO: Need is known positive check.
4730     return false;
4731   }
4732   case AMDGPUISD::LDEXP:
4733   case AMDGPUISD::FRACT: {
4734     if (SNaN)
4735       return true;
4736     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4737   }
4738   case AMDGPUISD::DIV_SCALE:
4739   case AMDGPUISD::DIV_FMAS:
4740   case AMDGPUISD::DIV_FIXUP:
4741     // TODO: Refine on operands.
4742     return SNaN;
4743   case AMDGPUISD::SIN_HW:
4744   case AMDGPUISD::COS_HW: {
4745     // TODO: Need check for infinity
4746     return SNaN;
4747   }
4748   case ISD::INTRINSIC_WO_CHAIN: {
4749     unsigned IntrinsicID
4750       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4751     // TODO: Handle more intrinsics
4752     switch (IntrinsicID) {
4753     case Intrinsic::amdgcn_cubeid:
4754       return true;
4755 
4756     case Intrinsic::amdgcn_frexp_mant: {
4757       if (SNaN)
4758         return true;
4759       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4760     }
4761     case Intrinsic::amdgcn_cvt_pkrtz: {
4762       if (SNaN)
4763         return true;
4764       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4765              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4766     }
4767     case Intrinsic::amdgcn_rcp:
4768     case Intrinsic::amdgcn_rsq:
4769     case Intrinsic::amdgcn_rcp_legacy:
4770     case Intrinsic::amdgcn_rsq_legacy:
4771     case Intrinsic::amdgcn_rsq_clamp: {
4772       if (SNaN)
4773         return true;
4774 
4775       // TODO: Need is known positive check.
4776       return false;
4777     }
4778     case Intrinsic::amdgcn_trig_preop:
4779     case Intrinsic::amdgcn_fdot2:
4780       // TODO: Refine on operand
4781       return SNaN;
4782     default:
4783       return false;
4784     }
4785   }
4786   default:
4787     return false;
4788   }
4789 }
4790 
4791 TargetLowering::AtomicExpansionKind
4792 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4793   switch (RMW->getOperation()) {
4794   case AtomicRMWInst::Nand:
4795   case AtomicRMWInst::FAdd:
4796   case AtomicRMWInst::FSub:
4797     return AtomicExpansionKind::CmpXChg;
4798   default:
4799     return AtomicExpansionKind::None;
4800   }
4801 }
4802