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   // There are no 64-bit extloads. These should be done as a 32-bit extload and
111   // an extension to 64-bit.
112   for (MVT VT : MVT::integer_valuetypes()) {
113     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
114     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
115     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
116   }
117 
118   for (MVT VT : MVT::integer_valuetypes()) {
119     if (VT == MVT::i64)
120       continue;
121 
122     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
123     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
124     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
125     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
126 
127     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
128     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
129     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
130     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
131 
132     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
133     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
134     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
135     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
136   }
137 
138   for (MVT VT : MVT::integer_fixedlen_vector_valuetypes()) {
139     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
140     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
141     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
142     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
143     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
144     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
145     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
146     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
147     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
148     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v3i16, Expand);
149     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v3i16, Expand);
150     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v3i16, Expand);
151     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
152     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
153     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
154   }
155 
156   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
157   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
158   setLoadExtAction(ISD::EXTLOAD, MVT::v3f32, MVT::v3f16, Expand);
159   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
160   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
161   setLoadExtAction(ISD::EXTLOAD, MVT::v16f32, MVT::v16f16, Expand);
162   setLoadExtAction(ISD::EXTLOAD, MVT::v32f32, MVT::v32f16, Expand);
163 
164   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
165   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
166   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
167   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
168 
169   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
170   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
171   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
172   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
173 
174   setOperationAction(ISD::STORE, MVT::f32, Promote);
175   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
176 
177   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
178   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
179 
180   setOperationAction(ISD::STORE, MVT::v3f32, Promote);
181   AddPromotedToType(ISD::STORE, MVT::v3f32, MVT::v3i32);
182 
183   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
184   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
185 
186   setOperationAction(ISD::STORE, MVT::v5f32, Promote);
187   AddPromotedToType(ISD::STORE, MVT::v5f32, MVT::v5i32);
188 
189   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
190   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
191 
192   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
193   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
194 
195   setOperationAction(ISD::STORE, MVT::v32f32, Promote);
196   AddPromotedToType(ISD::STORE, MVT::v32f32, MVT::v32i32);
197 
198   setOperationAction(ISD::STORE, MVT::i64, Promote);
199   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
200 
201   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
202   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
203 
204   setOperationAction(ISD::STORE, MVT::f64, Promote);
205   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
206 
207   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
208   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
209 
210   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
211   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
212   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
213   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
214 
215   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
216   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
217   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
218   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
219 
220   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
221   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
222   setTruncStoreAction(MVT::v3f32, MVT::v3f16, Expand);
223   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
224   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
225   setTruncStoreAction(MVT::v16f32, MVT::v16f16, Expand);
226   setTruncStoreAction(MVT::v32f32, MVT::v32f16, Expand);
227 
228   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
229   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
230 
231   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
232   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
233 
234   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
235   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
236 
237   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
238   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
239 
240 
241   setOperationAction(ISD::Constant, MVT::i32, Legal);
242   setOperationAction(ISD::Constant, MVT::i64, Legal);
243   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
244   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
245 
246   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
247   setOperationAction(ISD::BRIND, MVT::Other, Expand);
248 
249   // This is totally unsupported, just custom lower to produce an error.
250   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
251 
252   // Library functions.  These default to Expand, but we have instructions
253   // for them.
254   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
255   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
256   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
257   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
258   setOperationAction(ISD::FABS,   MVT::f32, Legal);
259   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
260   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
261   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
262   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
263   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
264 
265   setOperationAction(ISD::FROUND, MVT::f32, Custom);
266   setOperationAction(ISD::FROUND, MVT::f64, Custom);
267 
268   setOperationAction(ISD::FLOG, MVT::f32, Custom);
269   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
270   setOperationAction(ISD::FEXP, MVT::f32, Custom);
271 
272 
273   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
274   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
275 
276   setOperationAction(ISD::FREM, MVT::f32, Custom);
277   setOperationAction(ISD::FREM, MVT::f64, Custom);
278 
279   // Expand to fneg + fadd.
280   setOperationAction(ISD::FSUB, MVT::f64, Expand);
281 
282   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3i32, Custom);
283   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3f32, Custom);
284   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
285   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
286   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5i32, Custom);
287   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5f32, Custom);
288   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
289   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
290   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
291   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
292   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3f32, Custom);
293   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3i32, Custom);
294   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
295   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
296   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5f32, Custom);
297   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5i32, Custom);
298   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
299   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
300   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16f32, Custom);
301   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16i32, Custom);
302   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32f32, Custom);
303   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32i32, Custom);
304 
305   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
306   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
307   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
308 
309   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
310   for (MVT VT : ScalarIntVTs) {
311     // These should use [SU]DIVREM, so set them to expand
312     setOperationAction(ISD::SDIV, VT, Expand);
313     setOperationAction(ISD::UDIV, VT, Expand);
314     setOperationAction(ISD::SREM, VT, Expand);
315     setOperationAction(ISD::UREM, VT, Expand);
316 
317     // GPU does not have divrem function for signed or unsigned.
318     setOperationAction(ISD::SDIVREM, VT, Custom);
319     setOperationAction(ISD::UDIVREM, VT, Custom);
320 
321     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
322     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
323     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
324 
325     setOperationAction(ISD::BSWAP, VT, Expand);
326     setOperationAction(ISD::CTTZ, VT, Expand);
327     setOperationAction(ISD::CTLZ, VT, Expand);
328 
329     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
330     setOperationAction(ISD::ADDC, VT, Legal);
331     setOperationAction(ISD::SUBC, VT, Legal);
332     setOperationAction(ISD::ADDE, VT, Legal);
333     setOperationAction(ISD::SUBE, VT, Legal);
334   }
335 
336   // The hardware supports 32-bit FSHR, but not FSHL.
337   setOperationAction(ISD::FSHR, MVT::i32, Legal);
338 
339   // The hardware supports 32-bit ROTR, but not ROTL.
340   setOperationAction(ISD::ROTL, MVT::i32, Expand);
341   setOperationAction(ISD::ROTL, MVT::i64, Expand);
342   setOperationAction(ISD::ROTR, MVT::i64, Expand);
343 
344   setOperationAction(ISD::MUL, MVT::i64, Expand);
345   setOperationAction(ISD::MULHU, MVT::i64, Expand);
346   setOperationAction(ISD::MULHS, MVT::i64, Expand);
347   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
348   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
349   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
350   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
351   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
352 
353   setOperationAction(ISD::SMIN, MVT::i32, Legal);
354   setOperationAction(ISD::UMIN, MVT::i32, Legal);
355   setOperationAction(ISD::SMAX, MVT::i32, Legal);
356   setOperationAction(ISD::UMAX, MVT::i32, Legal);
357 
358   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
359   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
360   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
361   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
362 
363   static const MVT::SimpleValueType VectorIntTypes[] = {
364     MVT::v2i32, MVT::v3i32, MVT::v4i32, MVT::v5i32
365   };
366 
367   for (MVT VT : VectorIntTypes) {
368     // Expand the following operations for the current type by default.
369     setOperationAction(ISD::ADD,  VT, Expand);
370     setOperationAction(ISD::AND,  VT, Expand);
371     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
372     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
373     setOperationAction(ISD::MUL,  VT, Expand);
374     setOperationAction(ISD::MULHU, VT, Expand);
375     setOperationAction(ISD::MULHS, VT, Expand);
376     setOperationAction(ISD::OR,   VT, Expand);
377     setOperationAction(ISD::SHL,  VT, Expand);
378     setOperationAction(ISD::SRA,  VT, Expand);
379     setOperationAction(ISD::SRL,  VT, Expand);
380     setOperationAction(ISD::ROTL, VT, Expand);
381     setOperationAction(ISD::ROTR, VT, Expand);
382     setOperationAction(ISD::SUB,  VT, Expand);
383     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
384     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
385     setOperationAction(ISD::SDIV, VT, Expand);
386     setOperationAction(ISD::UDIV, VT, Expand);
387     setOperationAction(ISD::SREM, VT, Expand);
388     setOperationAction(ISD::UREM, VT, Expand);
389     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
390     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
391     setOperationAction(ISD::SDIVREM, VT, Custom);
392     setOperationAction(ISD::UDIVREM, VT, Expand);
393     setOperationAction(ISD::SELECT, VT, Expand);
394     setOperationAction(ISD::VSELECT, VT, Expand);
395     setOperationAction(ISD::SELECT_CC, VT, Expand);
396     setOperationAction(ISD::XOR,  VT, Expand);
397     setOperationAction(ISD::BSWAP, VT, Expand);
398     setOperationAction(ISD::CTPOP, VT, Expand);
399     setOperationAction(ISD::CTTZ, VT, Expand);
400     setOperationAction(ISD::CTLZ, VT, Expand);
401     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
402     setOperationAction(ISD::SETCC, VT, Expand);
403   }
404 
405   static const MVT::SimpleValueType FloatVectorTypes[] = {
406      MVT::v2f32, MVT::v3f32, MVT::v4f32, MVT::v5f32
407   };
408 
409   for (MVT VT : FloatVectorTypes) {
410     setOperationAction(ISD::FABS, VT, Expand);
411     setOperationAction(ISD::FMINNUM, VT, Expand);
412     setOperationAction(ISD::FMAXNUM, VT, Expand);
413     setOperationAction(ISD::FADD, VT, Expand);
414     setOperationAction(ISD::FCEIL, VT, Expand);
415     setOperationAction(ISD::FCOS, VT, Expand);
416     setOperationAction(ISD::FDIV, VT, Expand);
417     setOperationAction(ISD::FEXP2, VT, Expand);
418     setOperationAction(ISD::FEXP, VT, Expand);
419     setOperationAction(ISD::FLOG2, VT, Expand);
420     setOperationAction(ISD::FREM, VT, Expand);
421     setOperationAction(ISD::FLOG, VT, Expand);
422     setOperationAction(ISD::FLOG10, VT, Expand);
423     setOperationAction(ISD::FPOW, VT, Expand);
424     setOperationAction(ISD::FFLOOR, VT, Expand);
425     setOperationAction(ISD::FTRUNC, VT, Expand);
426     setOperationAction(ISD::FMUL, VT, Expand);
427     setOperationAction(ISD::FMA, VT, Expand);
428     setOperationAction(ISD::FRINT, VT, Expand);
429     setOperationAction(ISD::FNEARBYINT, VT, Expand);
430     setOperationAction(ISD::FSQRT, VT, Expand);
431     setOperationAction(ISD::FSIN, VT, Expand);
432     setOperationAction(ISD::FSUB, VT, Expand);
433     setOperationAction(ISD::FNEG, VT, Expand);
434     setOperationAction(ISD::VSELECT, VT, Expand);
435     setOperationAction(ISD::SELECT_CC, VT, Expand);
436     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
437     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
438     setOperationAction(ISD::SETCC, VT, Expand);
439     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
440   }
441 
442   // This causes using an unrolled select operation rather than expansion with
443   // bit operations. This is in general better, but the alternative using BFI
444   // instructions may be better if the select sources are SGPRs.
445   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
446   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
447 
448   setOperationAction(ISD::SELECT, MVT::v3f32, Promote);
449   AddPromotedToType(ISD::SELECT, MVT::v3f32, MVT::v3i32);
450 
451   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
452   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
453 
454   setOperationAction(ISD::SELECT, MVT::v5f32, Promote);
455   AddPromotedToType(ISD::SELECT, MVT::v5f32, MVT::v5i32);
456 
457   // There are no libcalls of any kind.
458   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
459     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
460 
461   setSchedulingPreference(Sched::RegPressure);
462   setJumpIsExpensive(true);
463 
464   // FIXME: This is only partially true. If we have to do vector compares, any
465   // SGPR pair can be a condition register. If we have a uniform condition, we
466   // are better off doing SALU operations, where there is only one SCC. For now,
467   // we don't have a way of knowing during instruction selection if a condition
468   // will be uniform and we always use vector compares. Assume we are using
469   // vector compares until that is fixed.
470   setHasMultipleConditionRegisters(true);
471 
472   setMinCmpXchgSizeInBits(32);
473   setSupportsUnalignedAtomics(false);
474 
475   PredictableSelectIsExpensive = false;
476 
477   // We want to find all load dependencies for long chains of stores to enable
478   // merging into very wide vectors. The problem is with vectors with > 4
479   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
480   // vectors are a legal type, even though we have to split the loads
481   // usually. When we can more precisely specify load legality per address
482   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
483   // smarter so that they can figure out what to do in 2 iterations without all
484   // N > 4 stores on the same chain.
485   GatherAllAliasesMaxDepth = 16;
486 
487   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
488   // about these during lowering.
489   MaxStoresPerMemcpy  = 0xffffffff;
490   MaxStoresPerMemmove = 0xffffffff;
491   MaxStoresPerMemset  = 0xffffffff;
492 
493   // The expansion for 64-bit division is enormous.
494   if (AMDGPUBypassSlowDiv)
495     addBypassSlowDiv(64, 32);
496 
497   setTargetDAGCombine(ISD::BITCAST);
498   setTargetDAGCombine(ISD::SHL);
499   setTargetDAGCombine(ISD::SRA);
500   setTargetDAGCombine(ISD::SRL);
501   setTargetDAGCombine(ISD::TRUNCATE);
502   setTargetDAGCombine(ISD::MUL);
503   setTargetDAGCombine(ISD::MULHU);
504   setTargetDAGCombine(ISD::MULHS);
505   setTargetDAGCombine(ISD::SELECT);
506   setTargetDAGCombine(ISD::SELECT_CC);
507   setTargetDAGCombine(ISD::STORE);
508   setTargetDAGCombine(ISD::FADD);
509   setTargetDAGCombine(ISD::FSUB);
510   setTargetDAGCombine(ISD::FNEG);
511   setTargetDAGCombine(ISD::FABS);
512   setTargetDAGCombine(ISD::AssertZext);
513   setTargetDAGCombine(ISD::AssertSext);
514   setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
515 }
516 
517 //===----------------------------------------------------------------------===//
518 // Target Information
519 //===----------------------------------------------------------------------===//
520 
521 LLVM_READNONE
522 static bool fnegFoldsIntoOp(unsigned Opc) {
523   switch (Opc) {
524   case ISD::FADD:
525   case ISD::FSUB:
526   case ISD::FMUL:
527   case ISD::FMA:
528   case ISD::FMAD:
529   case ISD::FMINNUM:
530   case ISD::FMAXNUM:
531   case ISD::FMINNUM_IEEE:
532   case ISD::FMAXNUM_IEEE:
533   case ISD::FSIN:
534   case ISD::FTRUNC:
535   case ISD::FRINT:
536   case ISD::FNEARBYINT:
537   case ISD::FCANONICALIZE:
538   case AMDGPUISD::RCP:
539   case AMDGPUISD::RCP_LEGACY:
540   case AMDGPUISD::RCP_IFLAG:
541   case AMDGPUISD::SIN_HW:
542   case AMDGPUISD::FMUL_LEGACY:
543   case AMDGPUISD::FMIN_LEGACY:
544   case AMDGPUISD::FMAX_LEGACY:
545   case AMDGPUISD::FMED3:
546     return true;
547   default:
548     return false;
549   }
550 }
551 
552 /// \p returns true if the operation will definitely need to use a 64-bit
553 /// encoding, and thus will use a VOP3 encoding regardless of the source
554 /// modifiers.
555 LLVM_READONLY
556 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
557   return N->getNumOperands() > 2 || VT == MVT::f64;
558 }
559 
560 // Most FP instructions support source modifiers, but this could be refined
561 // slightly.
562 LLVM_READONLY
563 static bool hasSourceMods(const SDNode *N) {
564   if (isa<MemSDNode>(N))
565     return false;
566 
567   switch (N->getOpcode()) {
568   case ISD::CopyToReg:
569   case ISD::SELECT:
570   case ISD::FDIV:
571   case ISD::FREM:
572   case ISD::INLINEASM:
573   case ISD::INLINEASM_BR:
574   case AMDGPUISD::DIV_SCALE:
575   case ISD::INTRINSIC_W_CHAIN:
576 
577   // TODO: Should really be looking at the users of the bitcast. These are
578   // problematic because bitcasts are used to legalize all stores to integer
579   // types.
580   case ISD::BITCAST:
581     return false;
582   case ISD::INTRINSIC_WO_CHAIN: {
583     switch (cast<ConstantSDNode>(N->getOperand(0))->getZExtValue()) {
584     case Intrinsic::amdgcn_interp_p1:
585     case Intrinsic::amdgcn_interp_p2:
586     case Intrinsic::amdgcn_interp_mov:
587     case Intrinsic::amdgcn_interp_p1_f16:
588     case Intrinsic::amdgcn_interp_p2_f16:
589       return false;
590     default:
591       return true;
592     }
593   }
594   default:
595     return true;
596   }
597 }
598 
599 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
600                                                  unsigned CostThreshold) {
601   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
602   // it is truly free to use a source modifier in all cases. If there are
603   // multiple users but for each one will necessitate using VOP3, there will be
604   // a code size increase. Try to avoid increasing code size unless we know it
605   // will save on the instruction count.
606   unsigned NumMayIncreaseSize = 0;
607   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
608 
609   // XXX - Should this limit number of uses to check?
610   for (const SDNode *U : N->uses()) {
611     if (!hasSourceMods(U))
612       return false;
613 
614     if (!opMustUseVOP3Encoding(U, VT)) {
615       if (++NumMayIncreaseSize > CostThreshold)
616         return false;
617     }
618   }
619 
620   return true;
621 }
622 
623 EVT AMDGPUTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
624                                               ISD::NodeType ExtendKind) const {
625   assert(!VT.isVector() && "only scalar expected");
626 
627   // Round to the next multiple of 32-bits.
628   unsigned Size = VT.getSizeInBits();
629   if (Size <= 32)
630     return MVT::i32;
631   return EVT::getIntegerVT(Context, 32 * ((Size + 31) / 32));
632 }
633 
634 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
635   return MVT::i32;
636 }
637 
638 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
639   return true;
640 }
641 
642 // The backend supports 32 and 64 bit floating point immediates.
643 // FIXME: Why are we reporting vectors of FP immediates as legal?
644 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
645                                         bool ForCodeSize) const {
646   EVT ScalarVT = VT.getScalarType();
647   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
648          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
649 }
650 
651 // We don't want to shrink f64 / f32 constants.
652 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
653   EVT ScalarVT = VT.getScalarType();
654   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
655 }
656 
657 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
658                                                  ISD::LoadExtType ExtTy,
659                                                  EVT NewVT) const {
660   // TODO: This may be worth removing. Check regression tests for diffs.
661   if (!TargetLoweringBase::shouldReduceLoadWidth(N, ExtTy, NewVT))
662     return false;
663 
664   unsigned NewSize = NewVT.getStoreSizeInBits();
665 
666   // If we are reducing to a 32-bit load or a smaller multi-dword load,
667   // this is always better.
668   if (NewSize >= 32)
669     return true;
670 
671   EVT OldVT = N->getValueType(0);
672   unsigned OldSize = OldVT.getStoreSizeInBits();
673 
674   MemSDNode *MN = cast<MemSDNode>(N);
675   unsigned AS = MN->getAddressSpace();
676   // Do not shrink an aligned scalar load to sub-dword.
677   // Scalar engine cannot do sub-dword loads.
678   if (OldSize >= 32 && NewSize < 32 && MN->getAlignment() >= 4 &&
679       (AS == AMDGPUAS::CONSTANT_ADDRESS ||
680        AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT ||
681        (isa<LoadSDNode>(N) &&
682         AS == AMDGPUAS::GLOBAL_ADDRESS && MN->isInvariant())) &&
683       AMDGPUInstrInfo::isUniformMMO(MN->getMemOperand()))
684     return false;
685 
686   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
687   // extloads, so doing one requires using a buffer_load. In cases where we
688   // still couldn't use a scalar load, using the wider load shouldn't really
689   // hurt anything.
690 
691   // If the old size already had to be an extload, there's no harm in continuing
692   // to reduce the width.
693   return (OldSize < 32);
694 }
695 
696 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy, EVT CastTy,
697                                                    const SelectionDAG &DAG,
698                                                    const MachineMemOperand &MMO) const {
699 
700   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
701 
702   if (LoadTy.getScalarType() == MVT::i32)
703     return false;
704 
705   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
706   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
707 
708   if ((LScalarSize >= CastScalarSize) && (CastScalarSize < 32))
709     return false;
710 
711   bool Fast = false;
712   return allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
713                                         CastTy, MMO, &Fast) &&
714          Fast;
715 }
716 
717 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
718 // profitable with the expansion for 64-bit since it's generally good to
719 // speculate things.
720 // FIXME: These should really have the size as a parameter.
721 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
722   return true;
723 }
724 
725 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
726   return true;
727 }
728 
729 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
730   switch (N->getOpcode()) {
731     default:
732     return false;
733     case ISD::EntryToken:
734     case ISD::TokenFactor:
735       return true;
736     case ISD::INTRINSIC_WO_CHAIN:
737     {
738       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
739       switch (IntrID) {
740         default:
741         return false;
742         case Intrinsic::amdgcn_readfirstlane:
743         case Intrinsic::amdgcn_readlane:
744           return true;
745       }
746     }
747     break;
748     case ISD::LOAD:
749     {
750       if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
751           AMDGPUAS::CONSTANT_ADDRESS_32BIT)
752         return true;
753       return false;
754     }
755     break;
756   }
757 }
758 
759 TargetLowering::NegatibleCost
760 AMDGPUTargetLowering::getNegatibleCost(SDValue Op, SelectionDAG &DAG,
761                                        bool LegalOperations, bool ForCodeSize,
762                                        unsigned Depth) const {
763   switch (Op.getOpcode()) {
764   case ISD::FMA:
765   case ISD::FMAD: {
766     // Negating a fma is not free if it has users without source mods.
767     if (!allUsesHaveSourceMods(Op.getNode()))
768       return NegatibleCost::Expensive;
769     break;
770   }
771   default:
772     break;
773   }
774 
775   return TargetLowering::getNegatibleCost(Op, DAG, LegalOperations, ForCodeSize,
776                                           Depth);
777 }
778 
779 //===---------------------------------------------------------------------===//
780 // Target Properties
781 //===---------------------------------------------------------------------===//
782 
783 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
784   assert(VT.isFloatingPoint());
785 
786   // Packed operations do not have a fabs modifier.
787   return VT == MVT::f32 || VT == MVT::f64 ||
788          (Subtarget->has16BitInsts() && VT == MVT::f16);
789 }
790 
791 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
792   assert(VT.isFloatingPoint());
793   return VT == MVT::f32 || VT == MVT::f64 ||
794          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
795          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
796 }
797 
798 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
799                                                          unsigned NumElem,
800                                                          unsigned AS) const {
801   return true;
802 }
803 
804 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
805   // There are few operations which truly have vector input operands. Any vector
806   // operation is going to involve operations on each component, and a
807   // build_vector will be a copy per element, so it always makes sense to use a
808   // build_vector input in place of the extracted element to avoid a copy into a
809   // super register.
810   //
811   // We should probably only do this if all users are extracts only, but this
812   // should be the common case.
813   return true;
814 }
815 
816 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
817   // Truncate is just accessing a subregister.
818 
819   unsigned SrcSize = Source.getSizeInBits();
820   unsigned DestSize = Dest.getSizeInBits();
821 
822   return DestSize < SrcSize && DestSize % 32 == 0 ;
823 }
824 
825 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
826   // Truncate is just accessing a subregister.
827 
828   unsigned SrcSize = Source->getScalarSizeInBits();
829   unsigned DestSize = Dest->getScalarSizeInBits();
830 
831   if (DestSize== 16 && Subtarget->has16BitInsts())
832     return SrcSize >= 32;
833 
834   return DestSize < SrcSize && DestSize % 32 == 0;
835 }
836 
837 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
838   unsigned SrcSize = Src->getScalarSizeInBits();
839   unsigned DestSize = Dest->getScalarSizeInBits();
840 
841   if (SrcSize == 16 && Subtarget->has16BitInsts())
842     return DestSize >= 32;
843 
844   return SrcSize == 32 && DestSize == 64;
845 }
846 
847 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
848   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
849   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
850   // this will enable reducing 64-bit operations the 32-bit, which is always
851   // good.
852 
853   if (Src == MVT::i16)
854     return Dest == MVT::i32 ||Dest == MVT::i64 ;
855 
856   return Src == MVT::i32 && Dest == MVT::i64;
857 }
858 
859 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
860   return isZExtFree(Val.getValueType(), VT2);
861 }
862 
863 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
864   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
865   // limited number of native 64-bit operations. Shrinking an operation to fit
866   // in a single 32-bit register should always be helpful. As currently used,
867   // this is much less general than the name suggests, and is only used in
868   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
869   // not profitable, and may actually be harmful.
870   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
871 }
872 
873 //===---------------------------------------------------------------------===//
874 // TargetLowering Callbacks
875 //===---------------------------------------------------------------------===//
876 
877 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
878                                                   bool IsVarArg) {
879   switch (CC) {
880   case CallingConv::AMDGPU_VS:
881   case CallingConv::AMDGPU_GS:
882   case CallingConv::AMDGPU_PS:
883   case CallingConv::AMDGPU_CS:
884   case CallingConv::AMDGPU_HS:
885   case CallingConv::AMDGPU_ES:
886   case CallingConv::AMDGPU_LS:
887     return CC_AMDGPU;
888   case CallingConv::C:
889   case CallingConv::Fast:
890   case CallingConv::Cold:
891     return CC_AMDGPU_Func;
892   case CallingConv::AMDGPU_KERNEL:
893   case CallingConv::SPIR_KERNEL:
894   default:
895     report_fatal_error("Unsupported calling convention for call");
896   }
897 }
898 
899 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
900                                                     bool IsVarArg) {
901   switch (CC) {
902   case CallingConv::AMDGPU_KERNEL:
903   case CallingConv::SPIR_KERNEL:
904     llvm_unreachable("kernels should not be handled here");
905   case CallingConv::AMDGPU_VS:
906   case CallingConv::AMDGPU_GS:
907   case CallingConv::AMDGPU_PS:
908   case CallingConv::AMDGPU_CS:
909   case CallingConv::AMDGPU_HS:
910   case CallingConv::AMDGPU_ES:
911   case CallingConv::AMDGPU_LS:
912     return RetCC_SI_Shader;
913   case CallingConv::C:
914   case CallingConv::Fast:
915   case CallingConv::Cold:
916     return RetCC_AMDGPU_Func;
917   default:
918     report_fatal_error("Unsupported calling convention.");
919   }
920 }
921 
922 /// The SelectionDAGBuilder will automatically promote function arguments
923 /// with illegal types.  However, this does not work for the AMDGPU targets
924 /// since the function arguments are stored in memory as these illegal types.
925 /// In order to handle this properly we need to get the original types sizes
926 /// from the LLVM IR Function and fixup the ISD:InputArg values before
927 /// passing them to AnalyzeFormalArguments()
928 
929 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
930 /// input values across multiple registers.  Each item in the Ins array
931 /// represents a single value that will be stored in registers.  Ins[x].VT is
932 /// the value type of the value that will be stored in the register, so
933 /// whatever SDNode we lower the argument to needs to be this type.
934 ///
935 /// In order to correctly lower the arguments we need to know the size of each
936 /// argument.  Since Ins[x].VT gives us the size of the register that will
937 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
938 /// for the orignal function argument so that we can deduce the correct memory
939 /// type to use for Ins[x].  In most cases the correct memory type will be
940 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
941 /// we have a kernel argument of type v8i8, this argument will be split into
942 /// 8 parts and each part will be represented by its own item in the Ins array.
943 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
944 /// the argument before it was split.  From this, we deduce that the memory type
945 /// for each individual part is i8.  We pass the memory type as LocVT to the
946 /// calling convention analysis function and the register type (Ins[x].VT) as
947 /// the ValVT.
948 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
949   CCState &State,
950   const SmallVectorImpl<ISD::InputArg> &Ins) const {
951   const MachineFunction &MF = State.getMachineFunction();
952   const Function &Fn = MF.getFunction();
953   LLVMContext &Ctx = Fn.getParent()->getContext();
954   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
955   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
956   CallingConv::ID CC = Fn.getCallingConv();
957 
958   unsigned MaxAlign = 1;
959   uint64_t ExplicitArgOffset = 0;
960   const DataLayout &DL = Fn.getParent()->getDataLayout();
961 
962   unsigned InIndex = 0;
963 
964   for (const Argument &Arg : Fn.args()) {
965     Type *BaseArgTy = Arg.getType();
966     unsigned Align = DL.getABITypeAlignment(BaseArgTy);
967     MaxAlign = std::max(Align, MaxAlign);
968     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
969 
970     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Align) + ExplicitOffset;
971     ExplicitArgOffset = alignTo(ExplicitArgOffset, Align) + AllocSize;
972 
973     // We're basically throwing away everything passed into us and starting over
974     // to get accurate in-memory offsets. The "PartOffset" is completely useless
975     // to us as computed in Ins.
976     //
977     // We also need to figure out what type legalization is trying to do to get
978     // the correct memory offsets.
979 
980     SmallVector<EVT, 16> ValueVTs;
981     SmallVector<uint64_t, 16> Offsets;
982     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
983 
984     for (unsigned Value = 0, NumValues = ValueVTs.size();
985          Value != NumValues; ++Value) {
986       uint64_t BasePartOffset = Offsets[Value];
987 
988       EVT ArgVT = ValueVTs[Value];
989       EVT MemVT = ArgVT;
990       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
991       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
992 
993       if (NumRegs == 1) {
994         // This argument is not split, so the IR type is the memory type.
995         if (ArgVT.isExtended()) {
996           // We have an extended type, like i24, so we should just use the
997           // register type.
998           MemVT = RegisterVT;
999         } else {
1000           MemVT = ArgVT;
1001         }
1002       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
1003                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
1004         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
1005         // We have a vector value which has been split into a vector with
1006         // the same scalar type, but fewer elements.  This should handle
1007         // all the floating-point vector types.
1008         MemVT = RegisterVT;
1009       } else if (ArgVT.isVector() &&
1010                  ArgVT.getVectorNumElements() == NumRegs) {
1011         // This arg has been split so that each element is stored in a separate
1012         // register.
1013         MemVT = ArgVT.getScalarType();
1014       } else if (ArgVT.isExtended()) {
1015         // We have an extended type, like i65.
1016         MemVT = RegisterVT;
1017       } else {
1018         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
1019         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
1020         if (RegisterVT.isInteger()) {
1021           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1022         } else if (RegisterVT.isVector()) {
1023           assert(!RegisterVT.getScalarType().isFloatingPoint());
1024           unsigned NumElements = RegisterVT.getVectorNumElements();
1025           assert(MemoryBits % NumElements == 0);
1026           // This vector type has been split into another vector type with
1027           // a different elements size.
1028           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1029                                            MemoryBits / NumElements);
1030           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1031         } else {
1032           llvm_unreachable("cannot deduce memory type.");
1033         }
1034       }
1035 
1036       // Convert one element vectors to scalar.
1037       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1038         MemVT = MemVT.getScalarType();
1039 
1040       // Round up vec3/vec5 argument.
1041       if (MemVT.isVector() && !MemVT.isPow2VectorType()) {
1042         assert(MemVT.getVectorNumElements() == 3 ||
1043                MemVT.getVectorNumElements() == 5);
1044         MemVT = MemVT.getPow2VectorType(State.getContext());
1045       } else if (!MemVT.isSimple() && !MemVT.isVector()) {
1046         MemVT = MemVT.getRoundIntegerType(State.getContext());
1047       }
1048 
1049       unsigned PartOffset = 0;
1050       for (unsigned i = 0; i != NumRegs; ++i) {
1051         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1052                                                BasePartOffset + PartOffset,
1053                                                MemVT.getSimpleVT(),
1054                                                CCValAssign::Full));
1055         PartOffset += MemVT.getStoreSize();
1056       }
1057     }
1058   }
1059 }
1060 
1061 SDValue AMDGPUTargetLowering::LowerReturn(
1062   SDValue Chain, CallingConv::ID CallConv,
1063   bool isVarArg,
1064   const SmallVectorImpl<ISD::OutputArg> &Outs,
1065   const SmallVectorImpl<SDValue> &OutVals,
1066   const SDLoc &DL, SelectionDAG &DAG) const {
1067   // FIXME: Fails for r600 tests
1068   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1069   // "wave terminate should not have return values");
1070   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1071 }
1072 
1073 //===---------------------------------------------------------------------===//
1074 // Target specific lowering
1075 //===---------------------------------------------------------------------===//
1076 
1077 /// Selects the correct CCAssignFn for a given CallingConvention value.
1078 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1079                                                     bool IsVarArg) {
1080   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1081 }
1082 
1083 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1084                                                       bool IsVarArg) {
1085   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1086 }
1087 
1088 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1089                                                   SelectionDAG &DAG,
1090                                                   MachineFrameInfo &MFI,
1091                                                   int ClobberedFI) const {
1092   SmallVector<SDValue, 8> ArgChains;
1093   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1094   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1095 
1096   // Include the original chain at the beginning of the list. When this is
1097   // used by target LowerCall hooks, this helps legalize find the
1098   // CALLSEQ_BEGIN node.
1099   ArgChains.push_back(Chain);
1100 
1101   // Add a chain value for each stack argument corresponding
1102   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1103                             UE = DAG.getEntryNode().getNode()->use_end();
1104        U != UE; ++U) {
1105     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1106       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1107         if (FI->getIndex() < 0) {
1108           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1109           int64_t InLastByte = InFirstByte;
1110           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1111 
1112           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1113               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1114             ArgChains.push_back(SDValue(L, 1));
1115         }
1116       }
1117     }
1118   }
1119 
1120   // Build a tokenfactor for all the chains.
1121   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1122 }
1123 
1124 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1125                                                  SmallVectorImpl<SDValue> &InVals,
1126                                                  StringRef Reason) const {
1127   SDValue Callee = CLI.Callee;
1128   SelectionDAG &DAG = CLI.DAG;
1129 
1130   const Function &Fn = DAG.getMachineFunction().getFunction();
1131 
1132   StringRef FuncName("<unknown>");
1133 
1134   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1135     FuncName = G->getSymbol();
1136   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1137     FuncName = G->getGlobal()->getName();
1138 
1139   DiagnosticInfoUnsupported NoCalls(
1140     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1141   DAG.getContext()->diagnose(NoCalls);
1142 
1143   if (!CLI.IsTailCall) {
1144     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1145       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1146   }
1147 
1148   return DAG.getEntryNode();
1149 }
1150 
1151 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1152                                         SmallVectorImpl<SDValue> &InVals) const {
1153   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1154 }
1155 
1156 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1157                                                       SelectionDAG &DAG) const {
1158   const Function &Fn = DAG.getMachineFunction().getFunction();
1159 
1160   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1161                                             SDLoc(Op).getDebugLoc());
1162   DAG.getContext()->diagnose(NoDynamicAlloca);
1163   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1164   return DAG.getMergeValues(Ops, SDLoc());
1165 }
1166 
1167 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1168                                              SelectionDAG &DAG) const {
1169   switch (Op.getOpcode()) {
1170   default:
1171     Op->print(errs(), &DAG);
1172     llvm_unreachable("Custom lowering code for this"
1173                      "instruction is not implemented yet!");
1174     break;
1175   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1176   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1177   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1178   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1179   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1180   case ISD::FREM: return LowerFREM(Op, DAG);
1181   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1182   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1183   case ISD::FRINT: return LowerFRINT(Op, DAG);
1184   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1185   case ISD::FROUND: return LowerFROUND(Op, DAG);
1186   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1187   case ISD::FLOG:
1188     return LowerFLOG(Op, DAG, 1.0F / numbers::log2ef);
1189   case ISD::FLOG10:
1190     return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
1191   case ISD::FEXP:
1192     return lowerFEXP(Op, DAG);
1193   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1194   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1195   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1196   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1197   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1198   case ISD::CTTZ:
1199   case ISD::CTTZ_ZERO_UNDEF:
1200   case ISD::CTLZ:
1201   case ISD::CTLZ_ZERO_UNDEF:
1202     return LowerCTLZ_CTTZ(Op, DAG);
1203   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1204   }
1205   return Op;
1206 }
1207 
1208 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1209                                               SmallVectorImpl<SDValue> &Results,
1210                                               SelectionDAG &DAG) const {
1211   switch (N->getOpcode()) {
1212   case ISD::SIGN_EXTEND_INREG:
1213     // Different parts of legalization seem to interpret which type of
1214     // sign_extend_inreg is the one to check for custom lowering. The extended
1215     // from type is what really matters, but some places check for custom
1216     // lowering of the result type. This results in trying to use
1217     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1218     // nothing here and let the illegal result integer be handled normally.
1219     return;
1220   default:
1221     return;
1222   }
1223 }
1224 
1225 bool AMDGPUTargetLowering::hasDefinedInitializer(const GlobalValue *GV) {
1226   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1227   if (!GVar || !GVar->hasInitializer())
1228     return false;
1229 
1230   return !isa<UndefValue>(GVar->getInitializer());
1231 }
1232 
1233 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1234                                                  SDValue Op,
1235                                                  SelectionDAG &DAG) const {
1236 
1237   const DataLayout &DL = DAG.getDataLayout();
1238   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1239   const GlobalValue *GV = G->getGlobal();
1240 
1241   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1242       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1243     if (!MFI->isEntryFunction()) {
1244       SDLoc DL(Op);
1245       const Function &Fn = DAG.getMachineFunction().getFunction();
1246       DiagnosticInfoUnsupported BadLDSDecl(
1247         Fn, "local memory global used by non-kernel function",
1248         DL.getDebugLoc(), DS_Warning);
1249       DAG.getContext()->diagnose(BadLDSDecl);
1250 
1251       // We currently don't have a way to correctly allocate LDS objects that
1252       // aren't directly associated with a kernel. We do force inlining of
1253       // functions that use local objects. However, if these dead functions are
1254       // not eliminated, we don't want a compile time error. Just emit a warning
1255       // and a trap, since there should be no callable path here.
1256       SDValue Trap = DAG.getNode(ISD::TRAP, DL, MVT::Other, DAG.getEntryNode());
1257       SDValue OutputChain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
1258                                         Trap, DAG.getRoot());
1259       DAG.setRoot(OutputChain);
1260       return DAG.getUNDEF(Op.getValueType());
1261     }
1262 
1263     // XXX: What does the value of G->getOffset() mean?
1264     assert(G->getOffset() == 0 &&
1265          "Do not know what to do with an non-zero offset");
1266 
1267     // TODO: We could emit code to handle the initialization somewhere.
1268     if (!hasDefinedInitializer(GV)) {
1269       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1270       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1271     }
1272   }
1273 
1274   const Function &Fn = DAG.getMachineFunction().getFunction();
1275   DiagnosticInfoUnsupported BadInit(
1276       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1277   DAG.getContext()->diagnose(BadInit);
1278   return SDValue();
1279 }
1280 
1281 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1282                                                   SelectionDAG &DAG) const {
1283   SmallVector<SDValue, 8> Args;
1284 
1285   EVT VT = Op.getValueType();
1286   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1287     SDLoc SL(Op);
1288     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1289     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1290 
1291     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1292     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1293   }
1294 
1295   for (const SDUse &U : Op->ops())
1296     DAG.ExtractVectorElements(U.get(), Args);
1297 
1298   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1299 }
1300 
1301 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1302                                                      SelectionDAG &DAG) const {
1303 
1304   SmallVector<SDValue, 8> Args;
1305   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1306   EVT VT = Op.getValueType();
1307   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1308                             VT.getVectorNumElements());
1309 
1310   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1311 }
1312 
1313 /// Generate Min/Max node
1314 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1315                                                    SDValue LHS, SDValue RHS,
1316                                                    SDValue True, SDValue False,
1317                                                    SDValue CC,
1318                                                    DAGCombinerInfo &DCI) const {
1319   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1320     return SDValue();
1321 
1322   SelectionDAG &DAG = DCI.DAG;
1323   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1324   switch (CCOpcode) {
1325   case ISD::SETOEQ:
1326   case ISD::SETONE:
1327   case ISD::SETUNE:
1328   case ISD::SETNE:
1329   case ISD::SETUEQ:
1330   case ISD::SETEQ:
1331   case ISD::SETFALSE:
1332   case ISD::SETFALSE2:
1333   case ISD::SETTRUE:
1334   case ISD::SETTRUE2:
1335   case ISD::SETUO:
1336   case ISD::SETO:
1337     break;
1338   case ISD::SETULE:
1339   case ISD::SETULT: {
1340     if (LHS == True)
1341       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1342     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1343   }
1344   case ISD::SETOLE:
1345   case ISD::SETOLT:
1346   case ISD::SETLE:
1347   case ISD::SETLT: {
1348     // Ordered. Assume ordered for undefined.
1349 
1350     // Only do this after legalization to avoid interfering with other combines
1351     // which might occur.
1352     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1353         !DCI.isCalledByLegalizer())
1354       return SDValue();
1355 
1356     // We need to permute the operands to get the correct NaN behavior. The
1357     // selected operand is the second one based on the failing compare with NaN,
1358     // so permute it based on the compare type the hardware uses.
1359     if (LHS == True)
1360       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1361     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1362   }
1363   case ISD::SETUGE:
1364   case ISD::SETUGT: {
1365     if (LHS == True)
1366       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1367     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1368   }
1369   case ISD::SETGT:
1370   case ISD::SETGE:
1371   case ISD::SETOGE:
1372   case ISD::SETOGT: {
1373     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1374         !DCI.isCalledByLegalizer())
1375       return SDValue();
1376 
1377     if (LHS == True)
1378       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1379     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1380   }
1381   case ISD::SETCC_INVALID:
1382     llvm_unreachable("Invalid setcc condcode!");
1383   }
1384   return SDValue();
1385 }
1386 
1387 std::pair<SDValue, SDValue>
1388 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1389   SDLoc SL(Op);
1390 
1391   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1392 
1393   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1394   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1395 
1396   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1397   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1398 
1399   return std::make_pair(Lo, Hi);
1400 }
1401 
1402 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1403   SDLoc SL(Op);
1404 
1405   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1406   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1407   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1408 }
1409 
1410 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1411   SDLoc SL(Op);
1412 
1413   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1414   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1415   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1416 }
1417 
1418 // Split a vector type into two parts. The first part is a power of two vector.
1419 // The second part is whatever is left over, and is a scalar if it would
1420 // otherwise be a 1-vector.
1421 std::pair<EVT, EVT>
1422 AMDGPUTargetLowering::getSplitDestVTs(const EVT &VT, SelectionDAG &DAG) const {
1423   EVT LoVT, HiVT;
1424   EVT EltVT = VT.getVectorElementType();
1425   unsigned NumElts = VT.getVectorNumElements();
1426   unsigned LoNumElts = PowerOf2Ceil((NumElts + 1) / 2);
1427   LoVT = EVT::getVectorVT(*DAG.getContext(), EltVT, LoNumElts);
1428   HiVT = NumElts - LoNumElts == 1
1429              ? EltVT
1430              : EVT::getVectorVT(*DAG.getContext(), EltVT, NumElts - LoNumElts);
1431   return std::make_pair(LoVT, HiVT);
1432 }
1433 
1434 // Split a vector value into two parts of types LoVT and HiVT. HiVT could be
1435 // scalar.
1436 std::pair<SDValue, SDValue>
1437 AMDGPUTargetLowering::splitVector(const SDValue &N, const SDLoc &DL,
1438                                   const EVT &LoVT, const EVT &HiVT,
1439                                   SelectionDAG &DAG) const {
1440   assert(LoVT.getVectorNumElements() +
1441                  (HiVT.isVector() ? HiVT.getVectorNumElements() : 1) <=
1442              N.getValueType().getVectorNumElements() &&
1443          "More vector elements requested than available!");
1444   SDValue Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, LoVT, N,
1445                            DAG.getVectorIdxConstant(0, DL));
1446   SDValue Hi = DAG.getNode(
1447       HiVT.isVector() ? ISD::EXTRACT_SUBVECTOR : ISD::EXTRACT_VECTOR_ELT, DL,
1448       HiVT, N, DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), DL));
1449   return std::make_pair(Lo, Hi);
1450 }
1451 
1452 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1453                                               SelectionDAG &DAG) const {
1454   LoadSDNode *Load = cast<LoadSDNode>(Op);
1455   EVT VT = Op.getValueType();
1456   SDLoc SL(Op);
1457 
1458 
1459   // If this is a 2 element vector, we really want to scalarize and not create
1460   // weird 1 element vectors.
1461   if (VT.getVectorNumElements() == 2) {
1462     SDValue Ops[2];
1463     std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(Load, DAG);
1464     return DAG.getMergeValues(Ops, SL);
1465   }
1466 
1467   SDValue BasePtr = Load->getBasePtr();
1468   EVT MemVT = Load->getMemoryVT();
1469 
1470   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1471 
1472   EVT LoVT, HiVT;
1473   EVT LoMemVT, HiMemVT;
1474   SDValue Lo, Hi;
1475 
1476   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1477   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1478   std::tie(Lo, Hi) = splitVector(Op, SL, LoVT, HiVT, DAG);
1479 
1480   unsigned Size = LoMemVT.getStoreSize();
1481   unsigned BaseAlign = Load->getAlignment();
1482   unsigned HiAlign = MinAlign(BaseAlign, Size);
1483 
1484   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1485                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1486                                   BaseAlign, Load->getMemOperand()->getFlags());
1487   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1488   SDValue HiLoad =
1489       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1490                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1491                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1492 
1493   SDValue Join;
1494   if (LoVT == HiVT) {
1495     // This is the case that the vector is power of two so was evenly split.
1496     Join = DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad);
1497   } else {
1498     Join = DAG.getNode(ISD::INSERT_SUBVECTOR, SL, VT, DAG.getUNDEF(VT), LoLoad,
1499                        DAG.getVectorIdxConstant(0, SL));
1500     Join = DAG.getNode(
1501         HiVT.isVector() ? ISD::INSERT_SUBVECTOR : ISD::INSERT_VECTOR_ELT, SL,
1502         VT, Join, HiLoad,
1503         DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), SL));
1504   }
1505 
1506   SDValue Ops[] = {Join, DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1507                                      LoLoad.getValue(1), HiLoad.getValue(1))};
1508 
1509   return DAG.getMergeValues(Ops, SL);
1510 }
1511 
1512 // Widen a vector load from vec3 to vec4.
1513 SDValue AMDGPUTargetLowering::WidenVectorLoad(SDValue Op,
1514                                               SelectionDAG &DAG) const {
1515   LoadSDNode *Load = cast<LoadSDNode>(Op);
1516   EVT VT = Op.getValueType();
1517   assert(VT.getVectorNumElements() == 3);
1518   SDValue BasePtr = Load->getBasePtr();
1519   EVT MemVT = Load->getMemoryVT();
1520   SDLoc SL(Op);
1521   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1522   unsigned BaseAlign = Load->getAlignment();
1523 
1524   EVT WideVT =
1525       EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(), 4);
1526   EVT WideMemVT =
1527       EVT::getVectorVT(*DAG.getContext(), MemVT.getVectorElementType(), 4);
1528   SDValue WideLoad = DAG.getExtLoad(
1529       Load->getExtensionType(), SL, WideVT, Load->getChain(), BasePtr, SrcValue,
1530       WideMemVT, BaseAlign, Load->getMemOperand()->getFlags());
1531   return DAG.getMergeValues(
1532       {DAG.getNode(ISD::EXTRACT_SUBVECTOR, SL, VT, WideLoad,
1533                    DAG.getVectorIdxConstant(0, SL)),
1534        WideLoad.getValue(1)},
1535       SL);
1536 }
1537 
1538 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1539                                                SelectionDAG &DAG) const {
1540   StoreSDNode *Store = cast<StoreSDNode>(Op);
1541   SDValue Val = Store->getValue();
1542   EVT VT = Val.getValueType();
1543 
1544   // If this is a 2 element vector, we really want to scalarize and not create
1545   // weird 1 element vectors.
1546   if (VT.getVectorNumElements() == 2)
1547     return scalarizeVectorStore(Store, DAG);
1548 
1549   EVT MemVT = Store->getMemoryVT();
1550   SDValue Chain = Store->getChain();
1551   SDValue BasePtr = Store->getBasePtr();
1552   SDLoc SL(Op);
1553 
1554   EVT LoVT, HiVT;
1555   EVT LoMemVT, HiMemVT;
1556   SDValue Lo, Hi;
1557 
1558   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1559   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1560   std::tie(Lo, Hi) = splitVector(Val, SL, LoVT, HiVT, DAG);
1561 
1562   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1563 
1564   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1565   unsigned BaseAlign = Store->getAlignment();
1566   unsigned Size = LoMemVT.getStoreSize();
1567   unsigned HiAlign = MinAlign(BaseAlign, Size);
1568 
1569   SDValue LoStore =
1570       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1571                         Store->getMemOperand()->getFlags());
1572   SDValue HiStore =
1573       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1574                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1575 
1576   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1577 }
1578 
1579 // This is a shortcut for integer division because we have fast i32<->f32
1580 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1581 // float is enough to accurately represent up to a 24-bit signed integer.
1582 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1583                                             bool Sign) const {
1584   SDLoc DL(Op);
1585   EVT VT = Op.getValueType();
1586   SDValue LHS = Op.getOperand(0);
1587   SDValue RHS = Op.getOperand(1);
1588   MVT IntVT = MVT::i32;
1589   MVT FltVT = MVT::f32;
1590 
1591   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1592   if (LHSSignBits < 9)
1593     return SDValue();
1594 
1595   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1596   if (RHSSignBits < 9)
1597     return SDValue();
1598 
1599   unsigned BitSize = VT.getSizeInBits();
1600   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1601   unsigned DivBits = BitSize - SignBits;
1602   if (Sign)
1603     ++DivBits;
1604 
1605   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1606   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1607 
1608   SDValue jq = DAG.getConstant(1, DL, IntVT);
1609 
1610   if (Sign) {
1611     // char|short jq = ia ^ ib;
1612     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1613 
1614     // jq = jq >> (bitsize - 2)
1615     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1616                      DAG.getConstant(BitSize - 2, DL, VT));
1617 
1618     // jq = jq | 0x1
1619     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1620   }
1621 
1622   // int ia = (int)LHS;
1623   SDValue ia = LHS;
1624 
1625   // int ib, (int)RHS;
1626   SDValue ib = RHS;
1627 
1628   // float fa = (float)ia;
1629   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1630 
1631   // float fb = (float)ib;
1632   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1633 
1634   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1635                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1636 
1637   // fq = trunc(fq);
1638   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1639 
1640   // float fqneg = -fq;
1641   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1642 
1643   MachineFunction &MF = DAG.getMachineFunction();
1644   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
1645 
1646   // float fr = mad(fqneg, fb, fa);
1647   unsigned OpCode = MFI->getMode().allFP32Denormals() ?
1648                     (unsigned)AMDGPUISD::FMAD_FTZ :
1649                     (unsigned)ISD::FMAD;
1650   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1651 
1652   // int iq = (int)fq;
1653   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1654 
1655   // fr = fabs(fr);
1656   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1657 
1658   // fb = fabs(fb);
1659   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1660 
1661   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1662 
1663   // int cv = fr >= fb;
1664   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1665 
1666   // jq = (cv ? jq : 0);
1667   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1668 
1669   // dst = iq + jq;
1670   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1671 
1672   // Rem needs compensation, it's easier to recompute it
1673   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1674   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1675 
1676   // Truncate to number of bits this divide really is.
1677   if (Sign) {
1678     SDValue InRegSize
1679       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1680     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1681     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1682   } else {
1683     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1684     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1685     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1686   }
1687 
1688   return DAG.getMergeValues({ Div, Rem }, DL);
1689 }
1690 
1691 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1692                                       SelectionDAG &DAG,
1693                                       SmallVectorImpl<SDValue> &Results) const {
1694   SDLoc DL(Op);
1695   EVT VT = Op.getValueType();
1696 
1697   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1698 
1699   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1700 
1701   SDValue One = DAG.getConstant(1, DL, HalfVT);
1702   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1703 
1704   //HiLo split
1705   SDValue LHS = Op.getOperand(0);
1706   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1707   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1708 
1709   SDValue RHS = Op.getOperand(1);
1710   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1711   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1712 
1713   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1714       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1715 
1716     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1717                               LHS_Lo, RHS_Lo);
1718 
1719     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1720     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1721 
1722     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1723     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1724     return;
1725   }
1726 
1727   if (isTypeLegal(MVT::i64)) {
1728     MachineFunction &MF = DAG.getMachineFunction();
1729     const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1730 
1731     // Compute denominator reciprocal.
1732     unsigned FMAD = MFI->getMode().allFP32Denormals() ?
1733                     (unsigned)AMDGPUISD::FMAD_FTZ :
1734                     (unsigned)ISD::FMAD;
1735 
1736     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1737     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1738     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1739       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1740       Cvt_Lo);
1741     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1742     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1743       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1744     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1745       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1746     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1747     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1748       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1749       Mul1);
1750     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1751     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1752     SDValue Rcp64 = DAG.getBitcast(VT,
1753                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1754 
1755     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1756     SDValue One64  = DAG.getConstant(1, DL, VT);
1757     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1758     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1759 
1760     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1761     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1762     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1763     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1764                                     Zero);
1765     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1766                                     One);
1767 
1768     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1769                                   Mulhi1_Lo, Zero1);
1770     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1771                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1772     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1773     SDValue Add1 = DAG.getBitcast(VT,
1774                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1775 
1776     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1777     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1778     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1779                                     Zero);
1780     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1781                                     One);
1782 
1783     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1784                                   Mulhi2_Lo, Zero1);
1785     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1786                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1787     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1788                                   Zero, Add2_Lo.getValue(1));
1789     SDValue Add2 = DAG.getBitcast(VT,
1790                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1791     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1792 
1793     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1794 
1795     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1796     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1797     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1798                                   Mul3_Lo, Zero1);
1799     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1800                                   Mul3_Hi, Sub1_Lo.getValue(1));
1801     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1802     SDValue Sub1 = DAG.getBitcast(VT,
1803                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1804 
1805     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1806     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1807                                  ISD::SETUGE);
1808     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1809                                  ISD::SETUGE);
1810     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1811 
1812     // TODO: Here and below portions of the code can be enclosed into if/endif.
1813     // Currently control flow is unconditional and we have 4 selects after
1814     // potential endif to substitute PHIs.
1815 
1816     // if C3 != 0 ...
1817     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1818                                   RHS_Lo, Zero1);
1819     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1820                                   RHS_Hi, Sub1_Lo.getValue(1));
1821     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1822                                   Zero, Sub2_Lo.getValue(1));
1823     SDValue Sub2 = DAG.getBitcast(VT,
1824                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1825 
1826     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1827 
1828     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1829                                  ISD::SETUGE);
1830     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1831                                  ISD::SETUGE);
1832     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1833 
1834     // if (C6 != 0)
1835     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1836 
1837     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1838                                   RHS_Lo, Zero1);
1839     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1840                                   RHS_Hi, Sub2_Lo.getValue(1));
1841     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1842                                   Zero, Sub3_Lo.getValue(1));
1843     SDValue Sub3 = DAG.getBitcast(VT,
1844                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1845 
1846     // endif C6
1847     // endif C3
1848 
1849     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1850     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1851 
1852     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1853     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1854 
1855     Results.push_back(Div);
1856     Results.push_back(Rem);
1857 
1858     return;
1859   }
1860 
1861   // r600 expandion.
1862   // Get Speculative values
1863   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1864   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1865 
1866   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1867   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1868   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1869 
1870   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1871   SDValue DIV_Lo = Zero;
1872 
1873   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1874 
1875   for (unsigned i = 0; i < halfBitWidth; ++i) {
1876     const unsigned bitPos = halfBitWidth - i - 1;
1877     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1878     // Get value of high bit
1879     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1880     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1881     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1882 
1883     // Shift
1884     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1885     // Add LHS high bit
1886     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1887 
1888     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1889     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1890 
1891     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1892 
1893     // Update REM
1894     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1895     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1896   }
1897 
1898   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1899   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1900   Results.push_back(DIV);
1901   Results.push_back(REM);
1902 }
1903 
1904 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1905                                            SelectionDAG &DAG) const {
1906   SDLoc DL(Op);
1907   EVT VT = Op.getValueType();
1908 
1909   if (VT == MVT::i64) {
1910     SmallVector<SDValue, 2> Results;
1911     LowerUDIVREM64(Op, DAG, Results);
1912     return DAG.getMergeValues(Results, DL);
1913   }
1914 
1915   if (VT == MVT::i32) {
1916     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1917       return Res;
1918   }
1919 
1920   SDValue Num = Op.getOperand(0);
1921   SDValue Den = Op.getOperand(1);
1922 
1923   // RCP =  URECIP(Den) = 2^32 / Den + e
1924   // e is rounding error.
1925   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1926 
1927   // RCP_LO = mul(RCP, Den) */
1928   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1929 
1930   // RCP_HI = mulhu (RCP, Den) */
1931   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1932 
1933   // NEG_RCP_LO = -RCP_LO
1934   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1935                                                      RCP_LO);
1936 
1937   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1938   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1939                                            NEG_RCP_LO, RCP_LO,
1940                                            ISD::SETEQ);
1941   // Calculate the rounding error from the URECIP instruction
1942   // E = mulhu(ABS_RCP_LO, RCP)
1943   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1944 
1945   // RCP_A_E = RCP + E
1946   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1947 
1948   // RCP_S_E = RCP - E
1949   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1950 
1951   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1952   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1953                                      RCP_A_E, RCP_S_E,
1954                                      ISD::SETEQ);
1955   // Quotient = mulhu(Tmp0, Num)
1956   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1957 
1958   // Num_S_Remainder = Quotient * Den
1959   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1960 
1961   // Remainder = Num - Num_S_Remainder
1962   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1963 
1964   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1965   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1966                                                  DAG.getConstant(-1, DL, VT),
1967                                                  DAG.getConstant(0, DL, VT),
1968                                                  ISD::SETUGE);
1969   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1970   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1971                                                   Num_S_Remainder,
1972                                                   DAG.getConstant(-1, DL, VT),
1973                                                   DAG.getConstant(0, DL, VT),
1974                                                   ISD::SETUGE);
1975   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1976   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1977                                                Remainder_GE_Zero);
1978 
1979   // Calculate Division result:
1980 
1981   // Quotient_A_One = Quotient + 1
1982   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1983                                        DAG.getConstant(1, DL, VT));
1984 
1985   // Quotient_S_One = Quotient - 1
1986   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1987                                        DAG.getConstant(1, DL, VT));
1988 
1989   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1990   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1991                                      Quotient, Quotient_A_One, ISD::SETEQ);
1992 
1993   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1994   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1995                             Quotient_S_One, Div, ISD::SETEQ);
1996 
1997   // Calculate Rem result:
1998 
1999   // Remainder_S_Den = Remainder - Den
2000   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
2001 
2002   // Remainder_A_Den = Remainder + Den
2003   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
2004 
2005   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
2006   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
2007                                     Remainder, Remainder_S_Den, ISD::SETEQ);
2008 
2009   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
2010   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
2011                             Remainder_A_Den, Rem, ISD::SETEQ);
2012   SDValue Ops[2] = {
2013     Div,
2014     Rem
2015   };
2016   return DAG.getMergeValues(Ops, DL);
2017 }
2018 
2019 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
2020                                            SelectionDAG &DAG) const {
2021   SDLoc DL(Op);
2022   EVT VT = Op.getValueType();
2023 
2024   SDValue LHS = Op.getOperand(0);
2025   SDValue RHS = Op.getOperand(1);
2026 
2027   SDValue Zero = DAG.getConstant(0, DL, VT);
2028   SDValue NegOne = DAG.getConstant(-1, DL, VT);
2029 
2030   if (VT == MVT::i32) {
2031     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
2032       return Res;
2033   }
2034 
2035   if (VT == MVT::i64 &&
2036       DAG.ComputeNumSignBits(LHS) > 32 &&
2037       DAG.ComputeNumSignBits(RHS) > 32) {
2038     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
2039 
2040     //HiLo split
2041     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
2042     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
2043     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
2044                                  LHS_Lo, RHS_Lo);
2045     SDValue Res[2] = {
2046       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
2047       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
2048     };
2049     return DAG.getMergeValues(Res, DL);
2050   }
2051 
2052   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
2053   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
2054   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
2055   SDValue RSign = LHSign; // Remainder sign is the same as LHS
2056 
2057   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
2058   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
2059 
2060   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
2061   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
2062 
2063   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
2064   SDValue Rem = Div.getValue(1);
2065 
2066   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
2067   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
2068 
2069   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
2070   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
2071 
2072   SDValue Res[2] = {
2073     Div,
2074     Rem
2075   };
2076   return DAG.getMergeValues(Res, DL);
2077 }
2078 
2079 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2080 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2081   SDLoc SL(Op);
2082   EVT VT = Op.getValueType();
2083   SDValue X = Op.getOperand(0);
2084   SDValue Y = Op.getOperand(1);
2085 
2086   // TODO: Should this propagate fast-math-flags?
2087 
2088   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2089   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2090   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2091 
2092   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2093 }
2094 
2095 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2096   SDLoc SL(Op);
2097   SDValue Src = Op.getOperand(0);
2098 
2099   // result = trunc(src)
2100   // if (src > 0.0 && src != result)
2101   //   result += 1.0
2102 
2103   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2104 
2105   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2106   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2107 
2108   EVT SetCCVT =
2109       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2110 
2111   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2112   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2113   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2114 
2115   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2116   // TODO: Should this propagate fast-math-flags?
2117   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2118 }
2119 
2120 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2121                                   SelectionDAG &DAG) {
2122   const unsigned FractBits = 52;
2123   const unsigned ExpBits = 11;
2124 
2125   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2126                                 Hi,
2127                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2128                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2129   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2130                             DAG.getConstant(1023, SL, MVT::i32));
2131 
2132   return Exp;
2133 }
2134 
2135 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2136   SDLoc SL(Op);
2137   SDValue Src = Op.getOperand(0);
2138 
2139   assert(Op.getValueType() == MVT::f64);
2140 
2141   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2142   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2143 
2144   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2145 
2146   // Extract the upper half, since this is where we will find the sign and
2147   // exponent.
2148   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2149 
2150   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2151 
2152   const unsigned FractBits = 52;
2153 
2154   // Extract the sign bit.
2155   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2156   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2157 
2158   // Extend back to 64-bits.
2159   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2160   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2161 
2162   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2163   const SDValue FractMask
2164     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2165 
2166   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2167   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2168   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2169 
2170   EVT SetCCVT =
2171       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2172 
2173   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2174 
2175   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2176   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2177 
2178   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2179   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2180 
2181   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2182 }
2183 
2184 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2185   SDLoc SL(Op);
2186   SDValue Src = Op.getOperand(0);
2187 
2188   assert(Op.getValueType() == MVT::f64);
2189 
2190   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2191   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2192   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2193 
2194   // TODO: Should this propagate fast-math-flags?
2195 
2196   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2197   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2198 
2199   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2200 
2201   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2202   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2203 
2204   EVT SetCCVT =
2205       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2206   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2207 
2208   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2209 }
2210 
2211 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2212   // FNEARBYINT and FRINT are the same, except in their handling of FP
2213   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2214   // rint, so just treat them as equivalent.
2215   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2216 }
2217 
2218 // XXX - May require not supporting f32 denormals?
2219 
2220 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2221 // compare and vselect end up producing worse code than scalarizing the whole
2222 // operation.
2223 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2224   SDLoc SL(Op);
2225   SDValue X = Op.getOperand(0);
2226   EVT VT = Op.getValueType();
2227 
2228   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2229 
2230   // TODO: Should this propagate fast-math-flags?
2231 
2232   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2233 
2234   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2235 
2236   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2237   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2238   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2239 
2240   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2241 
2242   EVT SetCCVT =
2243       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2244 
2245   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2246 
2247   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2248 
2249   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2250 }
2251 
2252 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2253   SDLoc SL(Op);
2254   SDValue Src = Op.getOperand(0);
2255 
2256   // result = trunc(src);
2257   // if (src < 0.0 && src != result)
2258   //   result += -1.0.
2259 
2260   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2261 
2262   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2263   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2264 
2265   EVT SetCCVT =
2266       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2267 
2268   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2269   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2270   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2271 
2272   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2273   // TODO: Should this propagate fast-math-flags?
2274   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2275 }
2276 
2277 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2278                                         double Log2BaseInverted) const {
2279   EVT VT = Op.getValueType();
2280 
2281   SDLoc SL(Op);
2282   SDValue Operand = Op.getOperand(0);
2283   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2284   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2285 
2286   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2287 }
2288 
2289 // exp2(M_LOG2E_F * f);
2290 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2291   EVT VT = Op.getValueType();
2292   SDLoc SL(Op);
2293   SDValue Src = Op.getOperand(0);
2294 
2295   const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
2296   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2297   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2298 }
2299 
2300 static bool isCtlzOpc(unsigned Opc) {
2301   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2302 }
2303 
2304 static bool isCttzOpc(unsigned Opc) {
2305   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2306 }
2307 
2308 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2309   SDLoc SL(Op);
2310   SDValue Src = Op.getOperand(0);
2311   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2312                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2313 
2314   unsigned ISDOpc, NewOpc;
2315   if (isCtlzOpc(Op.getOpcode())) {
2316     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2317     NewOpc = AMDGPUISD::FFBH_U32;
2318   } else if (isCttzOpc(Op.getOpcode())) {
2319     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2320     NewOpc = AMDGPUISD::FFBL_B32;
2321   } else
2322     llvm_unreachable("Unexpected OPCode!!!");
2323 
2324 
2325   if (ZeroUndef && Src.getValueType() == MVT::i32)
2326     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2327 
2328   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2329 
2330   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2331   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2332 
2333   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2334   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2335 
2336   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2337                                    *DAG.getContext(), MVT::i32);
2338 
2339   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2340   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2341 
2342   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2343   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2344 
2345   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2346   SDValue Add, NewOpr;
2347   if (isCtlzOpc(Op.getOpcode())) {
2348     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2349     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2350     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2351   } else {
2352     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2353     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2354     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2355   }
2356 
2357   if (!ZeroUndef) {
2358     // Test if the full 64-bit input is zero.
2359 
2360     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2361     // which we probably don't want.
2362     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2363     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2364     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2365 
2366     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2367     // with the same cycles, otherwise it is slower.
2368     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2369     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2370 
2371     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2372 
2373     // The instruction returns -1 for 0 input, but the defined intrinsic
2374     // behavior is to return the number of bits.
2375     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2376                          SrcIsZero, Bits32, NewOpr);
2377   }
2378 
2379   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2380 }
2381 
2382 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2383                                                bool Signed) const {
2384   // Unsigned
2385   // cul2f(ulong u)
2386   //{
2387   //  uint lz = clz(u);
2388   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2389   //  u = (u << lz) & 0x7fffffffffffffffUL;
2390   //  ulong t = u & 0xffffffffffUL;
2391   //  uint v = (e << 23) | (uint)(u >> 40);
2392   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2393   //  return as_float(v + r);
2394   //}
2395   // Signed
2396   // cl2f(long l)
2397   //{
2398   //  long s = l >> 63;
2399   //  float r = cul2f((l + s) ^ s);
2400   //  return s ? -r : r;
2401   //}
2402 
2403   SDLoc SL(Op);
2404   SDValue Src = Op.getOperand(0);
2405   SDValue L = Src;
2406 
2407   SDValue S;
2408   if (Signed) {
2409     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2410     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2411 
2412     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2413     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2414   }
2415 
2416   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2417                                    *DAG.getContext(), MVT::f32);
2418 
2419 
2420   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2421   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2422   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2423   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2424 
2425   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2426   SDValue E = DAG.getSelect(SL, MVT::i32,
2427     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2428     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2429     ZeroI32);
2430 
2431   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2432     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2433     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2434 
2435   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2436                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2437 
2438   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2439                              U, DAG.getConstant(40, SL, MVT::i64));
2440 
2441   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2442     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2443     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2444 
2445   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2446   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2447   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2448 
2449   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2450 
2451   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2452 
2453   SDValue R = DAG.getSelect(SL, MVT::i32,
2454     RCmp,
2455     One,
2456     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2457   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2458   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2459 
2460   if (!Signed)
2461     return R;
2462 
2463   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2464   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2465 }
2466 
2467 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2468                                                bool Signed) const {
2469   SDLoc SL(Op);
2470   SDValue Src = Op.getOperand(0);
2471 
2472   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2473 
2474   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2475                            DAG.getConstant(0, SL, MVT::i32));
2476   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2477                            DAG.getConstant(1, SL, MVT::i32));
2478 
2479   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2480                               SL, MVT::f64, Hi);
2481 
2482   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2483 
2484   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2485                               DAG.getConstant(32, SL, MVT::i32));
2486   // TODO: Should this propagate fast-math-flags?
2487   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2488 }
2489 
2490 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2491                                                SelectionDAG &DAG) const {
2492   // TODO: Factor out code common with LowerSINT_TO_FP.
2493   EVT DestVT = Op.getValueType();
2494   SDValue Src = Op.getOperand(0);
2495   EVT SrcVT = Src.getValueType();
2496 
2497   if (SrcVT == MVT::i16) {
2498     if (DestVT == MVT::f16)
2499       return Op;
2500     SDLoc DL(Op);
2501 
2502     // Promote src to i32
2503     SDValue Ext = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Src);
2504     return DAG.getNode(ISD::UINT_TO_FP, DL, DestVT, Ext);
2505   }
2506 
2507   assert(SrcVT == MVT::i64 && "operation should be legal");
2508 
2509   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2510     SDLoc DL(Op);
2511 
2512     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2513     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2514     SDValue FPRound =
2515         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2516 
2517     return FPRound;
2518   }
2519 
2520   if (DestVT == MVT::f32)
2521     return LowerINT_TO_FP32(Op, DAG, false);
2522 
2523   assert(DestVT == MVT::f64);
2524   return LowerINT_TO_FP64(Op, DAG, false);
2525 }
2526 
2527 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2528                                               SelectionDAG &DAG) const {
2529   EVT DestVT = Op.getValueType();
2530 
2531   SDValue Src = Op.getOperand(0);
2532   EVT SrcVT = Src.getValueType();
2533 
2534   if (SrcVT == MVT::i16) {
2535     if (DestVT == MVT::f16)
2536       return Op;
2537 
2538     SDLoc DL(Op);
2539     // Promote src to i32
2540     SDValue Ext = DAG.getNode(ISD::SIGN_EXTEND, DL, MVT::i32, Src);
2541     return DAG.getNode(ISD::SINT_TO_FP, DL, DestVT, Ext);
2542   }
2543 
2544   assert(SrcVT == MVT::i64 && "operation should be legal");
2545 
2546   // TODO: Factor out code common with LowerUINT_TO_FP.
2547 
2548   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2549     SDLoc DL(Op);
2550     SDValue Src = Op.getOperand(0);
2551 
2552     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2553     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2554     SDValue FPRound =
2555         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2556 
2557     return FPRound;
2558   }
2559 
2560   if (DestVT == MVT::f32)
2561     return LowerINT_TO_FP32(Op, DAG, true);
2562 
2563   assert(DestVT == MVT::f64);
2564   return LowerINT_TO_FP64(Op, DAG, true);
2565 }
2566 
2567 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2568                                                bool Signed) const {
2569   SDLoc SL(Op);
2570 
2571   SDValue Src = Op.getOperand(0);
2572 
2573   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2574 
2575   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2576                                  MVT::f64);
2577   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2578                                  MVT::f64);
2579   // TODO: Should this propagate fast-math-flags?
2580   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2581 
2582   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2583 
2584 
2585   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2586 
2587   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2588                            MVT::i32, FloorMul);
2589   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2590 
2591   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2592 
2593   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2594 }
2595 
2596 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2597   SDLoc DL(Op);
2598   SDValue N0 = Op.getOperand(0);
2599 
2600   // Convert to target node to get known bits
2601   if (N0.getValueType() == MVT::f32)
2602     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2603 
2604   if (getTargetMachine().Options.UnsafeFPMath) {
2605     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2606     return SDValue();
2607   }
2608 
2609   assert(N0.getSimpleValueType() == MVT::f64);
2610 
2611   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2612   const unsigned ExpMask = 0x7ff;
2613   const unsigned ExpBiasf64 = 1023;
2614   const unsigned ExpBiasf16 = 15;
2615   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2616   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2617   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2618   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2619                            DAG.getConstant(32, DL, MVT::i64));
2620   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2621   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2622   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2623                           DAG.getConstant(20, DL, MVT::i64));
2624   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2625                   DAG.getConstant(ExpMask, DL, MVT::i32));
2626   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2627   // add the f16 bias (15) to get the biased exponent for the f16 format.
2628   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2629                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2630 
2631   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2632                           DAG.getConstant(8, DL, MVT::i32));
2633   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2634                   DAG.getConstant(0xffe, DL, MVT::i32));
2635 
2636   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2637                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2638   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2639 
2640   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2641   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2642 
2643   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2644   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2645       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2646                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2647 
2648   // N = M | (E << 12);
2649   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2650       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2651                   DAG.getConstant(12, DL, MVT::i32)));
2652 
2653   // B = clamp(1-E, 0, 13);
2654   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2655                                   One, E);
2656   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2657   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2658                   DAG.getConstant(13, DL, MVT::i32));
2659 
2660   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2661                                    DAG.getConstant(0x1000, DL, MVT::i32));
2662 
2663   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2664   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2665   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2666   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2667 
2668   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2669   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2670                               DAG.getConstant(0x7, DL, MVT::i32));
2671   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2672                   DAG.getConstant(2, DL, MVT::i32));
2673   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2674                                One, Zero, ISD::SETEQ);
2675   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2676                                One, Zero, ISD::SETGT);
2677   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2678   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2679 
2680   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2681                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2682   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2683                       I, V, ISD::SETEQ);
2684 
2685   // Extract the sign bit.
2686   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2687                             DAG.getConstant(16, DL, MVT::i32));
2688   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2689                      DAG.getConstant(0x8000, DL, MVT::i32));
2690 
2691   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2692   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2693 }
2694 
2695 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2696                                               SelectionDAG &DAG) const {
2697   SDValue Src = Op.getOperand(0);
2698 
2699   // TODO: Factor out code common with LowerFP_TO_UINT.
2700 
2701   EVT SrcVT = Src.getValueType();
2702   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2703     SDLoc DL(Op);
2704 
2705     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2706     SDValue FpToInt32 =
2707         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2708 
2709     return FpToInt32;
2710   }
2711 
2712   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2713     return LowerFP64_TO_INT(Op, DAG, true);
2714 
2715   return SDValue();
2716 }
2717 
2718 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2719                                               SelectionDAG &DAG) const {
2720   SDValue Src = Op.getOperand(0);
2721 
2722   // TODO: Factor out code common with LowerFP_TO_SINT.
2723 
2724   EVT SrcVT = Src.getValueType();
2725   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2726     SDLoc DL(Op);
2727 
2728     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2729     SDValue FpToInt32 =
2730         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2731 
2732     return FpToInt32;
2733   }
2734 
2735   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2736     return LowerFP64_TO_INT(Op, DAG, false);
2737 
2738   return SDValue();
2739 }
2740 
2741 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2742                                                      SelectionDAG &DAG) const {
2743   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2744   MVT VT = Op.getSimpleValueType();
2745   MVT ScalarVT = VT.getScalarType();
2746 
2747   assert(VT.isVector());
2748 
2749   SDValue Src = Op.getOperand(0);
2750   SDLoc DL(Op);
2751 
2752   // TODO: Don't scalarize on Evergreen?
2753   unsigned NElts = VT.getVectorNumElements();
2754   SmallVector<SDValue, 8> Args;
2755   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2756 
2757   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2758   for (unsigned I = 0; I < NElts; ++I)
2759     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2760 
2761   return DAG.getBuildVector(VT, DL, Args);
2762 }
2763 
2764 //===----------------------------------------------------------------------===//
2765 // Custom DAG optimizations
2766 //===----------------------------------------------------------------------===//
2767 
2768 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2769   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2770 }
2771 
2772 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2773   EVT VT = Op.getValueType();
2774   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2775                                      // as unsigned 24-bit values.
2776     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2777 }
2778 
2779 static SDValue simplifyI24(SDNode *Node24,
2780                            TargetLowering::DAGCombinerInfo &DCI) {
2781   SelectionDAG &DAG = DCI.DAG;
2782   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2783   bool IsIntrin = Node24->getOpcode() == ISD::INTRINSIC_WO_CHAIN;
2784 
2785   SDValue LHS = IsIntrin ? Node24->getOperand(1) : Node24->getOperand(0);
2786   SDValue RHS = IsIntrin ? Node24->getOperand(2) : Node24->getOperand(1);
2787   unsigned NewOpcode = Node24->getOpcode();
2788   if (IsIntrin) {
2789     unsigned IID = cast<ConstantSDNode>(Node24->getOperand(0))->getZExtValue();
2790     NewOpcode = IID == Intrinsic::amdgcn_mul_i24 ?
2791       AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
2792   }
2793 
2794   APInt Demanded = APInt::getLowBitsSet(LHS.getValueSizeInBits(), 24);
2795 
2796   // First try to simplify using SimplifyMultipleUseDemandedBits which allows
2797   // the operands to have other uses, but will only perform simplifications that
2798   // involve bypassing some nodes for this user.
2799   SDValue DemandedLHS = TLI.SimplifyMultipleUseDemandedBits(LHS, Demanded, DAG);
2800   SDValue DemandedRHS = TLI.SimplifyMultipleUseDemandedBits(RHS, Demanded, DAG);
2801   if (DemandedLHS || DemandedRHS)
2802     return DAG.getNode(NewOpcode, SDLoc(Node24), Node24->getVTList(),
2803                        DemandedLHS ? DemandedLHS : LHS,
2804                        DemandedRHS ? DemandedRHS : RHS);
2805 
2806   // Now try SimplifyDemandedBits which can simplify the nodes used by our
2807   // operands if this node is the only user.
2808   if (TLI.SimplifyDemandedBits(LHS, Demanded, DCI))
2809     return SDValue(Node24, 0);
2810   if (TLI.SimplifyDemandedBits(RHS, Demanded, DCI))
2811     return SDValue(Node24, 0);
2812 
2813   return SDValue();
2814 }
2815 
2816 template <typename IntTy>
2817 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2818                                uint32_t Width, const SDLoc &DL) {
2819   if (Width + Offset < 32) {
2820     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2821     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2822     return DAG.getConstant(Result, DL, MVT::i32);
2823   }
2824 
2825   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2826 }
2827 
2828 static bool hasVolatileUser(SDNode *Val) {
2829   for (SDNode *U : Val->uses()) {
2830     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2831       if (M->isVolatile())
2832         return true;
2833     }
2834   }
2835 
2836   return false;
2837 }
2838 
2839 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2840   // i32 vectors are the canonical memory type.
2841   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2842     return false;
2843 
2844   if (!VT.isByteSized())
2845     return false;
2846 
2847   unsigned Size = VT.getStoreSize();
2848 
2849   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2850     return false;
2851 
2852   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2853     return false;
2854 
2855   return true;
2856 }
2857 
2858 // Replace load of an illegal type with a store of a bitcast to a friendlier
2859 // type.
2860 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2861                                                  DAGCombinerInfo &DCI) const {
2862   if (!DCI.isBeforeLegalize())
2863     return SDValue();
2864 
2865   LoadSDNode *LN = cast<LoadSDNode>(N);
2866   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2867     return SDValue();
2868 
2869   SDLoc SL(N);
2870   SelectionDAG &DAG = DCI.DAG;
2871   EVT VT = LN->getMemoryVT();
2872 
2873   unsigned Size = VT.getStoreSize();
2874   unsigned Align = LN->getAlignment();
2875   if (Align < Size && isTypeLegal(VT)) {
2876     bool IsFast;
2877     unsigned AS = LN->getAddressSpace();
2878 
2879     // Expand unaligned loads earlier than legalization. Due to visitation order
2880     // problems during legalization, the emitted instructions to pack and unpack
2881     // the bytes again are not eliminated in the case of an unaligned copy.
2882     if (!allowsMisalignedMemoryAccesses(
2883             VT, AS, Align, LN->getMemOperand()->getFlags(), &IsFast)) {
2884       SDValue Ops[2];
2885 
2886       if (VT.isVector())
2887         std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(LN, DAG);
2888       else
2889         std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2890 
2891       return DAG.getMergeValues(Ops, SDLoc(N));
2892     }
2893 
2894     if (!IsFast)
2895       return SDValue();
2896   }
2897 
2898   if (!shouldCombineMemoryType(VT))
2899     return SDValue();
2900 
2901   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2902 
2903   SDValue NewLoad
2904     = DAG.getLoad(NewVT, SL, LN->getChain(),
2905                   LN->getBasePtr(), LN->getMemOperand());
2906 
2907   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2908   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2909   return SDValue(N, 0);
2910 }
2911 
2912 // Replace store of an illegal type with a store of a bitcast to a friendlier
2913 // type.
2914 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2915                                                   DAGCombinerInfo &DCI) const {
2916   if (!DCI.isBeforeLegalize())
2917     return SDValue();
2918 
2919   StoreSDNode *SN = cast<StoreSDNode>(N);
2920   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2921     return SDValue();
2922 
2923   EVT VT = SN->getMemoryVT();
2924   unsigned Size = VT.getStoreSize();
2925 
2926   SDLoc SL(N);
2927   SelectionDAG &DAG = DCI.DAG;
2928   unsigned Align = SN->getAlignment();
2929   if (Align < Size && isTypeLegal(VT)) {
2930     bool IsFast;
2931     unsigned AS = SN->getAddressSpace();
2932 
2933     // Expand unaligned stores earlier than legalization. Due to visitation
2934     // order problems during legalization, the emitted instructions to pack and
2935     // unpack the bytes again are not eliminated in the case of an unaligned
2936     // copy.
2937     if (!allowsMisalignedMemoryAccesses(
2938             VT, AS, Align, SN->getMemOperand()->getFlags(), &IsFast)) {
2939       if (VT.isVector())
2940         return scalarizeVectorStore(SN, DAG);
2941 
2942       return expandUnalignedStore(SN, DAG);
2943     }
2944 
2945     if (!IsFast)
2946       return SDValue();
2947   }
2948 
2949   if (!shouldCombineMemoryType(VT))
2950     return SDValue();
2951 
2952   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2953   SDValue Val = SN->getValue();
2954 
2955   //DCI.AddToWorklist(Val.getNode());
2956 
2957   bool OtherUses = !Val.hasOneUse();
2958   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2959   if (OtherUses) {
2960     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2961     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2962   }
2963 
2964   return DAG.getStore(SN->getChain(), SL, CastVal,
2965                       SN->getBasePtr(), SN->getMemOperand());
2966 }
2967 
2968 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2969 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2970 // issues.
2971 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2972                                                         DAGCombinerInfo &DCI) const {
2973   SelectionDAG &DAG = DCI.DAG;
2974   SDValue N0 = N->getOperand(0);
2975 
2976   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2977   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2978   if (N0.getOpcode() == ISD::TRUNCATE) {
2979     SDValue N1 = N->getOperand(1);
2980     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2981     SDLoc SL(N);
2982 
2983     SDValue Src = N0.getOperand(0);
2984     EVT SrcVT = Src.getValueType();
2985     if (SrcVT.bitsGE(ExtVT)) {
2986       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2987       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2988     }
2989   }
2990 
2991   return SDValue();
2992 }
2993 
2994 SDValue AMDGPUTargetLowering::performIntrinsicWOChainCombine(
2995   SDNode *N, DAGCombinerInfo &DCI) const {
2996   unsigned IID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
2997   switch (IID) {
2998   case Intrinsic::amdgcn_mul_i24:
2999   case Intrinsic::amdgcn_mul_u24:
3000     return simplifyI24(N, DCI);
3001   default:
3002     return SDValue();
3003   }
3004 }
3005 
3006 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
3007 /// binary operation \p Opc to it with the corresponding constant operands.
3008 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
3009   DAGCombinerInfo &DCI, const SDLoc &SL,
3010   unsigned Opc, SDValue LHS,
3011   uint32_t ValLo, uint32_t ValHi) const {
3012   SelectionDAG &DAG = DCI.DAG;
3013   SDValue Lo, Hi;
3014   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
3015 
3016   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
3017   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
3018 
3019   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
3020   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
3021 
3022   // Re-visit the ands. It's possible we eliminated one of them and it could
3023   // simplify the vector.
3024   DCI.AddToWorklist(Lo.getNode());
3025   DCI.AddToWorklist(Hi.getNode());
3026 
3027   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
3028   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3029 }
3030 
3031 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
3032                                                 DAGCombinerInfo &DCI) const {
3033   EVT VT = N->getValueType(0);
3034 
3035   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3036   if (!RHS)
3037     return SDValue();
3038 
3039   SDValue LHS = N->getOperand(0);
3040   unsigned RHSVal = RHS->getZExtValue();
3041   if (!RHSVal)
3042     return LHS;
3043 
3044   SDLoc SL(N);
3045   SelectionDAG &DAG = DCI.DAG;
3046 
3047   switch (LHS->getOpcode()) {
3048   default:
3049     break;
3050   case ISD::ZERO_EXTEND:
3051   case ISD::SIGN_EXTEND:
3052   case ISD::ANY_EXTEND: {
3053     SDValue X = LHS->getOperand(0);
3054 
3055     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
3056         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
3057       // Prefer build_vector as the canonical form if packed types are legal.
3058       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
3059       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
3060        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
3061       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
3062     }
3063 
3064     // shl (ext x) => zext (shl x), if shift does not overflow int
3065     if (VT != MVT::i64)
3066       break;
3067     KnownBits Known = DAG.computeKnownBits(X);
3068     unsigned LZ = Known.countMinLeadingZeros();
3069     if (LZ < RHSVal)
3070       break;
3071     EVT XVT = X.getValueType();
3072     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
3073     return DAG.getZExtOrTrunc(Shl, SL, VT);
3074   }
3075   }
3076 
3077   if (VT != MVT::i64)
3078     return SDValue();
3079 
3080   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3081 
3082   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3083   // common case, splitting this into a move and a 32-bit shift is faster and
3084   // the same code size.
3085   if (RHSVal < 32)
3086     return SDValue();
3087 
3088   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3089 
3090   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3091   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3092 
3093   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3094 
3095   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3096   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3097 }
3098 
3099 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3100                                                 DAGCombinerInfo &DCI) const {
3101   if (N->getValueType(0) != MVT::i64)
3102     return SDValue();
3103 
3104   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3105   if (!RHS)
3106     return SDValue();
3107 
3108   SelectionDAG &DAG = DCI.DAG;
3109   SDLoc SL(N);
3110   unsigned RHSVal = RHS->getZExtValue();
3111 
3112   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3113   if (RHSVal == 32) {
3114     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3115     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3116                                    DAG.getConstant(31, SL, MVT::i32));
3117 
3118     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3119     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3120   }
3121 
3122   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3123   if (RHSVal == 63) {
3124     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3125     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3126                                    DAG.getConstant(31, SL, MVT::i32));
3127     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3128     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3129   }
3130 
3131   return SDValue();
3132 }
3133 
3134 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3135                                                 DAGCombinerInfo &DCI) const {
3136   auto *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3137   if (!RHS)
3138     return SDValue();
3139 
3140   EVT VT = N->getValueType(0);
3141   SDValue LHS = N->getOperand(0);
3142   unsigned ShiftAmt = RHS->getZExtValue();
3143   SelectionDAG &DAG = DCI.DAG;
3144   SDLoc SL(N);
3145 
3146   // fold (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1)
3147   // this improves the ability to match BFE patterns in isel.
3148   if (LHS.getOpcode() == ISD::AND) {
3149     if (auto *Mask = dyn_cast<ConstantSDNode>(LHS.getOperand(1))) {
3150       if (Mask->getAPIntValue().isShiftedMask() &&
3151           Mask->getAPIntValue().countTrailingZeros() == ShiftAmt) {
3152         return DAG.getNode(
3153             ISD::AND, SL, VT,
3154             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(0), N->getOperand(1)),
3155             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(1), N->getOperand(1)));
3156       }
3157     }
3158   }
3159 
3160   if (VT != MVT::i64)
3161     return SDValue();
3162 
3163   if (ShiftAmt < 32)
3164     return SDValue();
3165 
3166   // srl i64:x, C for C >= 32
3167   // =>
3168   //   build_pair (srl hi_32(x), C - 32), 0
3169   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3170   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3171 
3172   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, LHS);
3173   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecOp, One);
3174 
3175   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3176   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3177 
3178   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3179 
3180   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3181 }
3182 
3183 SDValue AMDGPUTargetLowering::performTruncateCombine(
3184   SDNode *N, DAGCombinerInfo &DCI) const {
3185   SDLoc SL(N);
3186   SelectionDAG &DAG = DCI.DAG;
3187   EVT VT = N->getValueType(0);
3188   SDValue Src = N->getOperand(0);
3189 
3190   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3191   if (Src.getOpcode() == ISD::BITCAST && !VT.isVector()) {
3192     SDValue Vec = Src.getOperand(0);
3193     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3194       SDValue Elt0 = Vec.getOperand(0);
3195       EVT EltVT = Elt0.getValueType();
3196       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3197         if (EltVT.isFloatingPoint()) {
3198           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3199                              EltVT.changeTypeToInteger(), Elt0);
3200         }
3201 
3202         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3203       }
3204     }
3205   }
3206 
3207   // Equivalent of above for accessing the high element of a vector as an
3208   // integer operation.
3209   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3210   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3211     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3212       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3213         SDValue BV = stripBitcast(Src.getOperand(0));
3214         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3215             BV.getValueType().getVectorNumElements() == 2) {
3216           SDValue SrcElt = BV.getOperand(1);
3217           EVT SrcEltVT = SrcElt.getValueType();
3218           if (SrcEltVT.isFloatingPoint()) {
3219             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3220                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3221           }
3222 
3223           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3224         }
3225       }
3226     }
3227   }
3228 
3229   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3230   //
3231   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3232   //     i16 (trunc (srl (i32 (trunc x), K)))
3233   if (VT.getScalarSizeInBits() < 32) {
3234     EVT SrcVT = Src.getValueType();
3235     if (SrcVT.getScalarSizeInBits() > 32 &&
3236         (Src.getOpcode() == ISD::SRL ||
3237          Src.getOpcode() == ISD::SRA ||
3238          Src.getOpcode() == ISD::SHL)) {
3239       SDValue Amt = Src.getOperand(1);
3240       KnownBits Known = DAG.computeKnownBits(Amt);
3241       unsigned Size = VT.getScalarSizeInBits();
3242       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3243           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3244         EVT MidVT = VT.isVector() ?
3245           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3246                            VT.getVectorNumElements()) : MVT::i32;
3247 
3248         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3249         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3250                                     Src.getOperand(0));
3251         DCI.AddToWorklist(Trunc.getNode());
3252 
3253         if (Amt.getValueType() != NewShiftVT) {
3254           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3255           DCI.AddToWorklist(Amt.getNode());
3256         }
3257 
3258         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3259                                           Trunc, Amt);
3260         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3261       }
3262     }
3263   }
3264 
3265   return SDValue();
3266 }
3267 
3268 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3269 // instructions. If we only match on the legalized i64 mul expansion,
3270 // SimplifyDemandedBits will be unable to remove them because there will be
3271 // multiple uses due to the separate mul + mulh[su].
3272 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3273                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3274   if (Size <= 32) {
3275     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3276     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3277   }
3278 
3279   // Because we want to eliminate extension instructions before the
3280   // operation, we need to create a single user here (i.e. not the separate
3281   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3282 
3283   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3284 
3285   SDValue Mul = DAG.getNode(MulOpc, SL,
3286                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3287 
3288   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3289                      Mul.getValue(0), Mul.getValue(1));
3290 }
3291 
3292 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3293                                                 DAGCombinerInfo &DCI) const {
3294   EVT VT = N->getValueType(0);
3295 
3296   unsigned Size = VT.getSizeInBits();
3297   if (VT.isVector() || Size > 64)
3298     return SDValue();
3299 
3300   // There are i16 integer mul/mad.
3301   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3302     return SDValue();
3303 
3304   SelectionDAG &DAG = DCI.DAG;
3305   SDLoc DL(N);
3306 
3307   SDValue N0 = N->getOperand(0);
3308   SDValue N1 = N->getOperand(1);
3309 
3310   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3311   // in the source into any_extends if the result of the mul is truncated. Since
3312   // we can assume the high bits are whatever we want, use the underlying value
3313   // to avoid the unknown high bits from interfering.
3314   if (N0.getOpcode() == ISD::ANY_EXTEND)
3315     N0 = N0.getOperand(0);
3316 
3317   if (N1.getOpcode() == ISD::ANY_EXTEND)
3318     N1 = N1.getOperand(0);
3319 
3320   SDValue Mul;
3321 
3322   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3323     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3324     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3325     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3326   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3327     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3328     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3329     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3330   } else {
3331     return SDValue();
3332   }
3333 
3334   // We need to use sext even for MUL_U24, because MUL_U24 is used
3335   // for signed multiply of 8 and 16-bit types.
3336   return DAG.getSExtOrTrunc(Mul, DL, VT);
3337 }
3338 
3339 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3340                                                   DAGCombinerInfo &DCI) const {
3341   EVT VT = N->getValueType(0);
3342 
3343   if (!Subtarget->hasMulI24() || VT.isVector())
3344     return SDValue();
3345 
3346   SelectionDAG &DAG = DCI.DAG;
3347   SDLoc DL(N);
3348 
3349   SDValue N0 = N->getOperand(0);
3350   SDValue N1 = N->getOperand(1);
3351 
3352   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3353     return SDValue();
3354 
3355   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3356   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3357 
3358   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3359   DCI.AddToWorklist(Mulhi.getNode());
3360   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3361 }
3362 
3363 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3364                                                   DAGCombinerInfo &DCI) const {
3365   EVT VT = N->getValueType(0);
3366 
3367   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3368     return SDValue();
3369 
3370   SelectionDAG &DAG = DCI.DAG;
3371   SDLoc DL(N);
3372 
3373   SDValue N0 = N->getOperand(0);
3374   SDValue N1 = N->getOperand(1);
3375 
3376   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3377     return SDValue();
3378 
3379   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3380   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3381 
3382   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3383   DCI.AddToWorklist(Mulhi.getNode());
3384   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3385 }
3386 
3387 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3388   SDNode *N, DAGCombinerInfo &DCI) const {
3389   SelectionDAG &DAG = DCI.DAG;
3390 
3391   // Simplify demanded bits before splitting into multiple users.
3392   if (SDValue V = simplifyI24(N, DCI))
3393     return V;
3394 
3395   SDValue N0 = N->getOperand(0);
3396   SDValue N1 = N->getOperand(1);
3397 
3398   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3399 
3400   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3401   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3402 
3403   SDLoc SL(N);
3404 
3405   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3406   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3407   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3408 }
3409 
3410 static bool isNegativeOne(SDValue Val) {
3411   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3412     return C->isAllOnesValue();
3413   return false;
3414 }
3415 
3416 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3417                                           SDValue Op,
3418                                           const SDLoc &DL,
3419                                           unsigned Opc) const {
3420   EVT VT = Op.getValueType();
3421   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3422   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3423                               LegalVT != MVT::i16))
3424     return SDValue();
3425 
3426   if (VT != MVT::i32)
3427     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3428 
3429   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3430   if (VT != MVT::i32)
3431     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3432 
3433   return FFBX;
3434 }
3435 
3436 // The native instructions return -1 on 0 input. Optimize out a select that
3437 // produces -1 on 0.
3438 //
3439 // TODO: If zero is not undef, we could also do this if the output is compared
3440 // against the bitwidth.
3441 //
3442 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3443 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3444                                                  SDValue LHS, SDValue RHS,
3445                                                  DAGCombinerInfo &DCI) const {
3446   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3447   if (!CmpRhs || !CmpRhs->isNullValue())
3448     return SDValue();
3449 
3450   SelectionDAG &DAG = DCI.DAG;
3451   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3452   SDValue CmpLHS = Cond.getOperand(0);
3453 
3454   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3455                                            AMDGPUISD::FFBH_U32;
3456 
3457   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3458   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3459   if (CCOpcode == ISD::SETEQ &&
3460       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3461       RHS.getOperand(0) == CmpLHS &&
3462       isNegativeOne(LHS)) {
3463     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3464   }
3465 
3466   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3467   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3468   if (CCOpcode == ISD::SETNE &&
3469       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3470       LHS.getOperand(0) == CmpLHS &&
3471       isNegativeOne(RHS)) {
3472     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3473   }
3474 
3475   return SDValue();
3476 }
3477 
3478 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3479                                          unsigned Op,
3480                                          const SDLoc &SL,
3481                                          SDValue Cond,
3482                                          SDValue N1,
3483                                          SDValue N2) {
3484   SelectionDAG &DAG = DCI.DAG;
3485   EVT VT = N1.getValueType();
3486 
3487   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3488                                   N1.getOperand(0), N2.getOperand(0));
3489   DCI.AddToWorklist(NewSelect.getNode());
3490   return DAG.getNode(Op, SL, VT, NewSelect);
3491 }
3492 
3493 // Pull a free FP operation out of a select so it may fold into uses.
3494 //
3495 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3496 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3497 //
3498 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3499 // select c, (fabs x), +k -> fabs (select c, x, k)
3500 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3501                                     SDValue N) {
3502   SelectionDAG &DAG = DCI.DAG;
3503   SDValue Cond = N.getOperand(0);
3504   SDValue LHS = N.getOperand(1);
3505   SDValue RHS = N.getOperand(2);
3506 
3507   EVT VT = N.getValueType();
3508   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3509       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3510     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3511                                      SDLoc(N), Cond, LHS, RHS);
3512   }
3513 
3514   bool Inv = false;
3515   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3516     std::swap(LHS, RHS);
3517     Inv = true;
3518   }
3519 
3520   // TODO: Support vector constants.
3521   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3522   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3523     SDLoc SL(N);
3524     // If one side is an fneg/fabs and the other is a constant, we can push the
3525     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3526     SDValue NewLHS = LHS.getOperand(0);
3527     SDValue NewRHS = RHS;
3528 
3529     // Careful: if the neg can be folded up, don't try to pull it back down.
3530     bool ShouldFoldNeg = true;
3531 
3532     if (NewLHS.hasOneUse()) {
3533       unsigned Opc = NewLHS.getOpcode();
3534       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3535         ShouldFoldNeg = false;
3536       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3537         ShouldFoldNeg = false;
3538     }
3539 
3540     if (ShouldFoldNeg) {
3541       if (LHS.getOpcode() == ISD::FNEG)
3542         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3543       else if (CRHS->isNegative())
3544         return SDValue();
3545 
3546       if (Inv)
3547         std::swap(NewLHS, NewRHS);
3548 
3549       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3550                                       Cond, NewLHS, NewRHS);
3551       DCI.AddToWorklist(NewSelect.getNode());
3552       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3553     }
3554   }
3555 
3556   return SDValue();
3557 }
3558 
3559 
3560 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3561                                                    DAGCombinerInfo &DCI) const {
3562   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3563     return Folded;
3564 
3565   SDValue Cond = N->getOperand(0);
3566   if (Cond.getOpcode() != ISD::SETCC)
3567     return SDValue();
3568 
3569   EVT VT = N->getValueType(0);
3570   SDValue LHS = Cond.getOperand(0);
3571   SDValue RHS = Cond.getOperand(1);
3572   SDValue CC = Cond.getOperand(2);
3573 
3574   SDValue True = N->getOperand(1);
3575   SDValue False = N->getOperand(2);
3576 
3577   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3578     SelectionDAG &DAG = DCI.DAG;
3579     if (DAG.isConstantValueOfAnyType(True) &&
3580         !DAG.isConstantValueOfAnyType(False)) {
3581       // Swap cmp + select pair to move constant to false input.
3582       // This will allow using VOPC cndmasks more often.
3583       // select (setcc x, y), k, x -> select (setccinv x, y), x, k
3584 
3585       SDLoc SL(N);
3586       ISD::CondCode NewCC =
3587           getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), LHS.getValueType());
3588 
3589       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3590       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3591     }
3592 
3593     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3594       SDValue MinMax
3595         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3596       // Revisit this node so we can catch min3/max3/med3 patterns.
3597       //DCI.AddToWorklist(MinMax.getNode());
3598       return MinMax;
3599     }
3600   }
3601 
3602   // There's no reason to not do this if the condition has other uses.
3603   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3604 }
3605 
3606 static bool isInv2Pi(const APFloat &APF) {
3607   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3608   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3609   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3610 
3611   return APF.bitwiseIsEqual(KF16) ||
3612          APF.bitwiseIsEqual(KF32) ||
3613          APF.bitwiseIsEqual(KF64);
3614 }
3615 
3616 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3617 // additional cost to negate them.
3618 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3619   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3620     if (C->isZero() && !C->isNegative())
3621       return true;
3622 
3623     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3624       return true;
3625   }
3626 
3627   return false;
3628 }
3629 
3630 static unsigned inverseMinMax(unsigned Opc) {
3631   switch (Opc) {
3632   case ISD::FMAXNUM:
3633     return ISD::FMINNUM;
3634   case ISD::FMINNUM:
3635     return ISD::FMAXNUM;
3636   case ISD::FMAXNUM_IEEE:
3637     return ISD::FMINNUM_IEEE;
3638   case ISD::FMINNUM_IEEE:
3639     return ISD::FMAXNUM_IEEE;
3640   case AMDGPUISD::FMAX_LEGACY:
3641     return AMDGPUISD::FMIN_LEGACY;
3642   case AMDGPUISD::FMIN_LEGACY:
3643     return  AMDGPUISD::FMAX_LEGACY;
3644   default:
3645     llvm_unreachable("invalid min/max opcode");
3646   }
3647 }
3648 
3649 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3650                                                  DAGCombinerInfo &DCI) const {
3651   SelectionDAG &DAG = DCI.DAG;
3652   SDValue N0 = N->getOperand(0);
3653   EVT VT = N->getValueType(0);
3654 
3655   unsigned Opc = N0.getOpcode();
3656 
3657   // If the input has multiple uses and we can either fold the negate down, or
3658   // the other uses cannot, give up. This both prevents unprofitable
3659   // transformations and infinite loops: we won't repeatedly try to fold around
3660   // a negate that has no 'good' form.
3661   if (N0.hasOneUse()) {
3662     // This may be able to fold into the source, but at a code size cost. Don't
3663     // fold if the fold into the user is free.
3664     if (allUsesHaveSourceMods(N, 0))
3665       return SDValue();
3666   } else {
3667     if (fnegFoldsIntoOp(Opc) &&
3668         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3669       return SDValue();
3670   }
3671 
3672   SDLoc SL(N);
3673   switch (Opc) {
3674   case ISD::FADD: {
3675     if (!mayIgnoreSignedZero(N0))
3676       return SDValue();
3677 
3678     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3679     SDValue LHS = N0.getOperand(0);
3680     SDValue RHS = N0.getOperand(1);
3681 
3682     if (LHS.getOpcode() != ISD::FNEG)
3683       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3684     else
3685       LHS = LHS.getOperand(0);
3686 
3687     if (RHS.getOpcode() != ISD::FNEG)
3688       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3689     else
3690       RHS = RHS.getOperand(0);
3691 
3692     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3693     if (Res.getOpcode() != ISD::FADD)
3694       return SDValue(); // Op got folded away.
3695     if (!N0.hasOneUse())
3696       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3697     return Res;
3698   }
3699   case ISD::FMUL:
3700   case AMDGPUISD::FMUL_LEGACY: {
3701     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3702     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3703     SDValue LHS = N0.getOperand(0);
3704     SDValue RHS = N0.getOperand(1);
3705 
3706     if (LHS.getOpcode() == ISD::FNEG)
3707       LHS = LHS.getOperand(0);
3708     else if (RHS.getOpcode() == ISD::FNEG)
3709       RHS = RHS.getOperand(0);
3710     else
3711       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3712 
3713     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3714     if (Res.getOpcode() != Opc)
3715       return SDValue(); // Op got folded away.
3716     if (!N0.hasOneUse())
3717       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3718     return Res;
3719   }
3720   case ISD::FMA:
3721   case ISD::FMAD: {
3722     if (!mayIgnoreSignedZero(N0))
3723       return SDValue();
3724 
3725     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3726     SDValue LHS = N0.getOperand(0);
3727     SDValue MHS = N0.getOperand(1);
3728     SDValue RHS = N0.getOperand(2);
3729 
3730     if (LHS.getOpcode() == ISD::FNEG)
3731       LHS = LHS.getOperand(0);
3732     else if (MHS.getOpcode() == ISD::FNEG)
3733       MHS = MHS.getOperand(0);
3734     else
3735       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3736 
3737     if (RHS.getOpcode() != ISD::FNEG)
3738       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3739     else
3740       RHS = RHS.getOperand(0);
3741 
3742     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3743     if (Res.getOpcode() != Opc)
3744       return SDValue(); // Op got folded away.
3745     if (!N0.hasOneUse())
3746       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3747     return Res;
3748   }
3749   case ISD::FMAXNUM:
3750   case ISD::FMINNUM:
3751   case ISD::FMAXNUM_IEEE:
3752   case ISD::FMINNUM_IEEE:
3753   case AMDGPUISD::FMAX_LEGACY:
3754   case AMDGPUISD::FMIN_LEGACY: {
3755     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3756     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3757     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3758     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3759 
3760     SDValue LHS = N0.getOperand(0);
3761     SDValue RHS = N0.getOperand(1);
3762 
3763     // 0 doesn't have a negated inline immediate.
3764     // TODO: This constant check should be generalized to other operations.
3765     if (isConstantCostlierToNegate(RHS))
3766       return SDValue();
3767 
3768     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3769     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3770     unsigned Opposite = inverseMinMax(Opc);
3771 
3772     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3773     if (Res.getOpcode() != Opposite)
3774       return SDValue(); // Op got folded away.
3775     if (!N0.hasOneUse())
3776       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3777     return Res;
3778   }
3779   case AMDGPUISD::FMED3: {
3780     SDValue Ops[3];
3781     for (unsigned I = 0; I < 3; ++I)
3782       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3783 
3784     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3785     if (Res.getOpcode() != AMDGPUISD::FMED3)
3786       return SDValue(); // Op got folded away.
3787     if (!N0.hasOneUse())
3788       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3789     return Res;
3790   }
3791   case ISD::FP_EXTEND:
3792   case ISD::FTRUNC:
3793   case ISD::FRINT:
3794   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3795   case ISD::FSIN:
3796   case ISD::FCANONICALIZE:
3797   case AMDGPUISD::RCP:
3798   case AMDGPUISD::RCP_LEGACY:
3799   case AMDGPUISD::RCP_IFLAG:
3800   case AMDGPUISD::SIN_HW: {
3801     SDValue CvtSrc = N0.getOperand(0);
3802     if (CvtSrc.getOpcode() == ISD::FNEG) {
3803       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3804       // (fneg (rcp (fneg x))) -> (rcp x)
3805       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3806     }
3807 
3808     if (!N0.hasOneUse())
3809       return SDValue();
3810 
3811     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3812     // (fneg (rcp x)) -> (rcp (fneg x))
3813     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3814     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3815   }
3816   case ISD::FP_ROUND: {
3817     SDValue CvtSrc = N0.getOperand(0);
3818 
3819     if (CvtSrc.getOpcode() == ISD::FNEG) {
3820       // (fneg (fp_round (fneg x))) -> (fp_round x)
3821       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3822                          CvtSrc.getOperand(0), N0.getOperand(1));
3823     }
3824 
3825     if (!N0.hasOneUse())
3826       return SDValue();
3827 
3828     // (fneg (fp_round x)) -> (fp_round (fneg x))
3829     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3830     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3831   }
3832   case ISD::FP16_TO_FP: {
3833     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3834     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3835     // Put the fneg back as a legal source operation that can be matched later.
3836     SDLoc SL(N);
3837 
3838     SDValue Src = N0.getOperand(0);
3839     EVT SrcVT = Src.getValueType();
3840 
3841     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3842     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3843                                   DAG.getConstant(0x8000, SL, SrcVT));
3844     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3845   }
3846   default:
3847     return SDValue();
3848   }
3849 }
3850 
3851 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3852                                                  DAGCombinerInfo &DCI) const {
3853   SelectionDAG &DAG = DCI.DAG;
3854   SDValue N0 = N->getOperand(0);
3855 
3856   if (!N0.hasOneUse())
3857     return SDValue();
3858 
3859   switch (N0.getOpcode()) {
3860   case ISD::FP16_TO_FP: {
3861     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3862     SDLoc SL(N);
3863     SDValue Src = N0.getOperand(0);
3864     EVT SrcVT = Src.getValueType();
3865 
3866     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3867     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3868                                   DAG.getConstant(0x7fff, SL, SrcVT));
3869     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3870   }
3871   default:
3872     return SDValue();
3873   }
3874 }
3875 
3876 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3877                                                 DAGCombinerInfo &DCI) const {
3878   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3879   if (!CFP)
3880     return SDValue();
3881 
3882   // XXX - Should this flush denormals?
3883   const APFloat &Val = CFP->getValueAPF();
3884   APFloat One(Val.getSemantics(), "1.0");
3885   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3886 }
3887 
3888 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3889                                                 DAGCombinerInfo &DCI) const {
3890   SelectionDAG &DAG = DCI.DAG;
3891   SDLoc DL(N);
3892 
3893   switch(N->getOpcode()) {
3894   default:
3895     break;
3896   case ISD::BITCAST: {
3897     EVT DestVT = N->getValueType(0);
3898 
3899     // Push casts through vector builds. This helps avoid emitting a large
3900     // number of copies when materializing floating point vector constants.
3901     //
3902     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3903     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3904     if (DestVT.isVector()) {
3905       SDValue Src = N->getOperand(0);
3906       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3907         EVT SrcVT = Src.getValueType();
3908         unsigned NElts = DestVT.getVectorNumElements();
3909 
3910         if (SrcVT.getVectorNumElements() == NElts) {
3911           EVT DestEltVT = DestVT.getVectorElementType();
3912 
3913           SmallVector<SDValue, 8> CastedElts;
3914           SDLoc SL(N);
3915           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3916             SDValue Elt = Src.getOperand(I);
3917             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3918           }
3919 
3920           return DAG.getBuildVector(DestVT, SL, CastedElts);
3921         }
3922       }
3923     }
3924 
3925     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3926       break;
3927 
3928     // Fold bitcasts of constants.
3929     //
3930     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3931     // TODO: Generalize and move to DAGCombiner
3932     SDValue Src = N->getOperand(0);
3933     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3934       if (Src.getValueType() == MVT::i64) {
3935         SDLoc SL(N);
3936         uint64_t CVal = C->getZExtValue();
3937         SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3938                                  DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3939                                  DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3940         return DAG.getNode(ISD::BITCAST, SL, DestVT, BV);
3941       }
3942     }
3943 
3944     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3945       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3946       SDLoc SL(N);
3947       uint64_t CVal = Val.getZExtValue();
3948       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3949                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3950                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3951 
3952       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3953     }
3954 
3955     break;
3956   }
3957   case ISD::SHL: {
3958     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3959       break;
3960 
3961     return performShlCombine(N, DCI);
3962   }
3963   case ISD::SRL: {
3964     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3965       break;
3966 
3967     return performSrlCombine(N, DCI);
3968   }
3969   case ISD::SRA: {
3970     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3971       break;
3972 
3973     return performSraCombine(N, DCI);
3974   }
3975   case ISD::TRUNCATE:
3976     return performTruncateCombine(N, DCI);
3977   case ISD::MUL:
3978     return performMulCombine(N, DCI);
3979   case ISD::MULHS:
3980     return performMulhsCombine(N, DCI);
3981   case ISD::MULHU:
3982     return performMulhuCombine(N, DCI);
3983   case AMDGPUISD::MUL_I24:
3984   case AMDGPUISD::MUL_U24:
3985   case AMDGPUISD::MULHI_I24:
3986   case AMDGPUISD::MULHI_U24: {
3987     if (SDValue V = simplifyI24(N, DCI))
3988       return V;
3989     return SDValue();
3990   }
3991   case AMDGPUISD::MUL_LOHI_I24:
3992   case AMDGPUISD::MUL_LOHI_U24:
3993     return performMulLoHi24Combine(N, DCI);
3994   case ISD::SELECT:
3995     return performSelectCombine(N, DCI);
3996   case ISD::FNEG:
3997     return performFNegCombine(N, DCI);
3998   case ISD::FABS:
3999     return performFAbsCombine(N, DCI);
4000   case AMDGPUISD::BFE_I32:
4001   case AMDGPUISD::BFE_U32: {
4002     assert(!N->getValueType(0).isVector() &&
4003            "Vector handling of BFE not implemented");
4004     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
4005     if (!Width)
4006       break;
4007 
4008     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
4009     if (WidthVal == 0)
4010       return DAG.getConstant(0, DL, MVT::i32);
4011 
4012     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
4013     if (!Offset)
4014       break;
4015 
4016     SDValue BitsFrom = N->getOperand(0);
4017     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
4018 
4019     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
4020 
4021     if (OffsetVal == 0) {
4022       // This is already sign / zero extended, so try to fold away extra BFEs.
4023       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
4024 
4025       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
4026       if (OpSignBits >= SignBits)
4027         return BitsFrom;
4028 
4029       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
4030       if (Signed) {
4031         // This is a sign_extend_inreg. Replace it to take advantage of existing
4032         // DAG Combines. If not eliminated, we will match back to BFE during
4033         // selection.
4034 
4035         // TODO: The sext_inreg of extended types ends, although we can could
4036         // handle them in a single BFE.
4037         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
4038                            DAG.getValueType(SmallVT));
4039       }
4040 
4041       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
4042     }
4043 
4044     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
4045       if (Signed) {
4046         return constantFoldBFE<int32_t>(DAG,
4047                                         CVal->getSExtValue(),
4048                                         OffsetVal,
4049                                         WidthVal,
4050                                         DL);
4051       }
4052 
4053       return constantFoldBFE<uint32_t>(DAG,
4054                                        CVal->getZExtValue(),
4055                                        OffsetVal,
4056                                        WidthVal,
4057                                        DL);
4058     }
4059 
4060     if ((OffsetVal + WidthVal) >= 32 &&
4061         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
4062       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
4063       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
4064                          BitsFrom, ShiftVal);
4065     }
4066 
4067     if (BitsFrom.hasOneUse()) {
4068       APInt Demanded = APInt::getBitsSet(32,
4069                                          OffsetVal,
4070                                          OffsetVal + WidthVal);
4071 
4072       KnownBits Known;
4073       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
4074                                             !DCI.isBeforeLegalizeOps());
4075       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
4076       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
4077           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
4078         DCI.CommitTargetLoweringOpt(TLO);
4079       }
4080     }
4081 
4082     break;
4083   }
4084   case ISD::LOAD:
4085     return performLoadCombine(N, DCI);
4086   case ISD::STORE:
4087     return performStoreCombine(N, DCI);
4088   case AMDGPUISD::RCP:
4089   case AMDGPUISD::RCP_IFLAG:
4090     return performRcpCombine(N, DCI);
4091   case ISD::AssertZext:
4092   case ISD::AssertSext:
4093     return performAssertSZExtCombine(N, DCI);
4094   case ISD::INTRINSIC_WO_CHAIN:
4095     return performIntrinsicWOChainCombine(N, DCI);
4096   }
4097   return SDValue();
4098 }
4099 
4100 //===----------------------------------------------------------------------===//
4101 // Helper functions
4102 //===----------------------------------------------------------------------===//
4103 
4104 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
4105                                                    const TargetRegisterClass *RC,
4106                                                    unsigned Reg, EVT VT,
4107                                                    const SDLoc &SL,
4108                                                    bool RawReg) const {
4109   MachineFunction &MF = DAG.getMachineFunction();
4110   MachineRegisterInfo &MRI = MF.getRegInfo();
4111   unsigned VReg;
4112 
4113   if (!MRI.isLiveIn(Reg)) {
4114     VReg = MRI.createVirtualRegister(RC);
4115     MRI.addLiveIn(Reg, VReg);
4116   } else {
4117     VReg = MRI.getLiveInVirtReg(Reg);
4118   }
4119 
4120   if (RawReg)
4121     return DAG.getRegister(VReg, VT);
4122 
4123   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
4124 }
4125 
4126 // This may be called multiple times, and nothing prevents creating multiple
4127 // objects at the same offset. See if we already defined this object.
4128 static int getOrCreateFixedStackObject(MachineFrameInfo &MFI, unsigned Size,
4129                                        int64_t Offset) {
4130   for (int I = MFI.getObjectIndexBegin(); I < 0; ++I) {
4131     if (MFI.getObjectOffset(I) == Offset) {
4132       assert(MFI.getObjectSize(I) == Size);
4133       return I;
4134     }
4135   }
4136 
4137   return MFI.CreateFixedObject(Size, Offset, true);
4138 }
4139 
4140 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
4141                                                   EVT VT,
4142                                                   const SDLoc &SL,
4143                                                   int64_t Offset) const {
4144   MachineFunction &MF = DAG.getMachineFunction();
4145   MachineFrameInfo &MFI = MF.getFrameInfo();
4146   int FI = getOrCreateFixedStackObject(MFI, VT.getStoreSize(), Offset);
4147 
4148   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4149   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4150 
4151   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4152                      MachineMemOperand::MODereferenceable |
4153                      MachineMemOperand::MOInvariant);
4154 }
4155 
4156 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4157                                                    const SDLoc &SL,
4158                                                    SDValue Chain,
4159                                                    SDValue ArgVal,
4160                                                    int64_t Offset) const {
4161   MachineFunction &MF = DAG.getMachineFunction();
4162   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4163 
4164   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4165   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4166                                MachineMemOperand::MODereferenceable);
4167   return Store;
4168 }
4169 
4170 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4171                                              const TargetRegisterClass *RC,
4172                                              EVT VT, const SDLoc &SL,
4173                                              const ArgDescriptor &Arg) const {
4174   assert(Arg && "Attempting to load missing argument");
4175 
4176   SDValue V = Arg.isRegister() ?
4177     CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL) :
4178     loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4179 
4180   if (!Arg.isMasked())
4181     return V;
4182 
4183   unsigned Mask = Arg.getMask();
4184   unsigned Shift = countTrailingZeros<unsigned>(Mask);
4185   V = DAG.getNode(ISD::SRL, SL, VT, V,
4186                   DAG.getShiftAmountConstant(Shift, VT, SL));
4187   return DAG.getNode(ISD::AND, SL, VT, V,
4188                      DAG.getConstant(Mask >> Shift, SL, VT));
4189 }
4190 
4191 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4192     const MachineFunction &MF, const ImplicitParameter Param) const {
4193   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4194   const AMDGPUSubtarget &ST =
4195       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4196   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4197   const Align Alignment = ST.getAlignmentForImplicitArgPtr();
4198   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4199                        ExplicitArgOffset;
4200   switch (Param) {
4201   case GRID_DIM:
4202     return ArgOffset;
4203   case GRID_OFFSET:
4204     return ArgOffset + 4;
4205   }
4206   llvm_unreachable("unexpected implicit parameter type");
4207 }
4208 
4209 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4210 
4211 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4212   switch ((AMDGPUISD::NodeType)Opcode) {
4213   case AMDGPUISD::FIRST_NUMBER: break;
4214   // AMDIL DAG nodes
4215   NODE_NAME_CASE(UMUL);
4216   NODE_NAME_CASE(BRANCH_COND);
4217 
4218   // AMDGPU DAG nodes
4219   NODE_NAME_CASE(IF)
4220   NODE_NAME_CASE(ELSE)
4221   NODE_NAME_CASE(LOOP)
4222   NODE_NAME_CASE(CALL)
4223   NODE_NAME_CASE(TC_RETURN)
4224   NODE_NAME_CASE(TRAP)
4225   NODE_NAME_CASE(RET_FLAG)
4226   NODE_NAME_CASE(RETURN_TO_EPILOG)
4227   NODE_NAME_CASE(ENDPGM)
4228   NODE_NAME_CASE(DWORDADDR)
4229   NODE_NAME_CASE(FRACT)
4230   NODE_NAME_CASE(SETCC)
4231   NODE_NAME_CASE(SETREG)
4232   NODE_NAME_CASE(DENORM_MODE)
4233   NODE_NAME_CASE(FMA_W_CHAIN)
4234   NODE_NAME_CASE(FMUL_W_CHAIN)
4235   NODE_NAME_CASE(CLAMP)
4236   NODE_NAME_CASE(COS_HW)
4237   NODE_NAME_CASE(SIN_HW)
4238   NODE_NAME_CASE(FMAX_LEGACY)
4239   NODE_NAME_CASE(FMIN_LEGACY)
4240   NODE_NAME_CASE(FMAX3)
4241   NODE_NAME_CASE(SMAX3)
4242   NODE_NAME_CASE(UMAX3)
4243   NODE_NAME_CASE(FMIN3)
4244   NODE_NAME_CASE(SMIN3)
4245   NODE_NAME_CASE(UMIN3)
4246   NODE_NAME_CASE(FMED3)
4247   NODE_NAME_CASE(SMED3)
4248   NODE_NAME_CASE(UMED3)
4249   NODE_NAME_CASE(FDOT2)
4250   NODE_NAME_CASE(URECIP)
4251   NODE_NAME_CASE(DIV_SCALE)
4252   NODE_NAME_CASE(DIV_FMAS)
4253   NODE_NAME_CASE(DIV_FIXUP)
4254   NODE_NAME_CASE(FMAD_FTZ)
4255   NODE_NAME_CASE(TRIG_PREOP)
4256   NODE_NAME_CASE(RCP)
4257   NODE_NAME_CASE(RSQ)
4258   NODE_NAME_CASE(RCP_LEGACY)
4259   NODE_NAME_CASE(RSQ_LEGACY)
4260   NODE_NAME_CASE(RCP_IFLAG)
4261   NODE_NAME_CASE(FMUL_LEGACY)
4262   NODE_NAME_CASE(RSQ_CLAMP)
4263   NODE_NAME_CASE(LDEXP)
4264   NODE_NAME_CASE(FP_CLASS)
4265   NODE_NAME_CASE(DOT4)
4266   NODE_NAME_CASE(CARRY)
4267   NODE_NAME_CASE(BORROW)
4268   NODE_NAME_CASE(BFE_U32)
4269   NODE_NAME_CASE(BFE_I32)
4270   NODE_NAME_CASE(BFI)
4271   NODE_NAME_CASE(BFM)
4272   NODE_NAME_CASE(FFBH_U32)
4273   NODE_NAME_CASE(FFBH_I32)
4274   NODE_NAME_CASE(FFBL_B32)
4275   NODE_NAME_CASE(MUL_U24)
4276   NODE_NAME_CASE(MUL_I24)
4277   NODE_NAME_CASE(MULHI_U24)
4278   NODE_NAME_CASE(MULHI_I24)
4279   NODE_NAME_CASE(MUL_LOHI_U24)
4280   NODE_NAME_CASE(MUL_LOHI_I24)
4281   NODE_NAME_CASE(MAD_U24)
4282   NODE_NAME_CASE(MAD_I24)
4283   NODE_NAME_CASE(MAD_I64_I32)
4284   NODE_NAME_CASE(MAD_U64_U32)
4285   NODE_NAME_CASE(PERM)
4286   NODE_NAME_CASE(TEXTURE_FETCH)
4287   NODE_NAME_CASE(R600_EXPORT)
4288   NODE_NAME_CASE(CONST_ADDRESS)
4289   NODE_NAME_CASE(REGISTER_LOAD)
4290   NODE_NAME_CASE(REGISTER_STORE)
4291   NODE_NAME_CASE(SAMPLE)
4292   NODE_NAME_CASE(SAMPLEB)
4293   NODE_NAME_CASE(SAMPLED)
4294   NODE_NAME_CASE(SAMPLEL)
4295   NODE_NAME_CASE(CVT_F32_UBYTE0)
4296   NODE_NAME_CASE(CVT_F32_UBYTE1)
4297   NODE_NAME_CASE(CVT_F32_UBYTE2)
4298   NODE_NAME_CASE(CVT_F32_UBYTE3)
4299   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4300   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4301   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4302   NODE_NAME_CASE(CVT_PK_I16_I32)
4303   NODE_NAME_CASE(CVT_PK_U16_U32)
4304   NODE_NAME_CASE(FP_TO_FP16)
4305   NODE_NAME_CASE(FP16_ZEXT)
4306   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4307   NODE_NAME_CASE(CONST_DATA_PTR)
4308   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4309   NODE_NAME_CASE(LDS)
4310   NODE_NAME_CASE(DUMMY_CHAIN)
4311   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4312   NODE_NAME_CASE(LOAD_D16_HI)
4313   NODE_NAME_CASE(LOAD_D16_LO)
4314   NODE_NAME_CASE(LOAD_D16_HI_I8)
4315   NODE_NAME_CASE(LOAD_D16_HI_U8)
4316   NODE_NAME_CASE(LOAD_D16_LO_I8)
4317   NODE_NAME_CASE(LOAD_D16_LO_U8)
4318   NODE_NAME_CASE(STORE_MSKOR)
4319   NODE_NAME_CASE(LOAD_CONSTANT)
4320   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4321   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4322   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4323   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4324   NODE_NAME_CASE(DS_ORDERED_COUNT)
4325   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4326   NODE_NAME_CASE(ATOMIC_INC)
4327   NODE_NAME_CASE(ATOMIC_DEC)
4328   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4329   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4330   NODE_NAME_CASE(BUFFER_LOAD)
4331   NODE_NAME_CASE(BUFFER_LOAD_UBYTE)
4332   NODE_NAME_CASE(BUFFER_LOAD_USHORT)
4333   NODE_NAME_CASE(BUFFER_LOAD_BYTE)
4334   NODE_NAME_CASE(BUFFER_LOAD_SHORT)
4335   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4336   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4337   NODE_NAME_CASE(SBUFFER_LOAD)
4338   NODE_NAME_CASE(BUFFER_STORE)
4339   NODE_NAME_CASE(BUFFER_STORE_BYTE)
4340   NODE_NAME_CASE(BUFFER_STORE_SHORT)
4341   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4342   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4343   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4344   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4345   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4346   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4347   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4348   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4349   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4350   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4351   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4352   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4353   NODE_NAME_CASE(BUFFER_ATOMIC_INC)
4354   NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
4355   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4356   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
4357   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)
4358   NODE_NAME_CASE(ATOMIC_PK_FADD)
4359 
4360   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4361   }
4362   return nullptr;
4363 }
4364 
4365 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4366                                               SelectionDAG &DAG, int Enabled,
4367                                               int &RefinementSteps,
4368                                               bool &UseOneConstNR,
4369                                               bool Reciprocal) const {
4370   EVT VT = Operand.getValueType();
4371 
4372   if (VT == MVT::f32) {
4373     RefinementSteps = 0;
4374     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4375   }
4376 
4377   // TODO: There is also f64 rsq instruction, but the documentation is less
4378   // clear on its precision.
4379 
4380   return SDValue();
4381 }
4382 
4383 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4384                                                SelectionDAG &DAG, int Enabled,
4385                                                int &RefinementSteps) const {
4386   EVT VT = Operand.getValueType();
4387 
4388   if (VT == MVT::f32) {
4389     // Reciprocal, < 1 ulp error.
4390     //
4391     // This reciprocal approximation converges to < 0.5 ulp error with one
4392     // newton rhapson performed with two fused multiple adds (FMAs).
4393 
4394     RefinementSteps = 0;
4395     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4396   }
4397 
4398   // TODO: There is also f64 rcp instruction, but the documentation is less
4399   // clear on its precision.
4400 
4401   return SDValue();
4402 }
4403 
4404 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4405     const SDValue Op, KnownBits &Known,
4406     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4407 
4408   Known.resetAll(); // Don't know anything.
4409 
4410   unsigned Opc = Op.getOpcode();
4411 
4412   switch (Opc) {
4413   default:
4414     break;
4415   case AMDGPUISD::CARRY:
4416   case AMDGPUISD::BORROW: {
4417     Known.Zero = APInt::getHighBitsSet(32, 31);
4418     break;
4419   }
4420 
4421   case AMDGPUISD::BFE_I32:
4422   case AMDGPUISD::BFE_U32: {
4423     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4424     if (!CWidth)
4425       return;
4426 
4427     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4428 
4429     if (Opc == AMDGPUISD::BFE_U32)
4430       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4431 
4432     break;
4433   }
4434   case AMDGPUISD::FP_TO_FP16:
4435   case AMDGPUISD::FP16_ZEXT: {
4436     unsigned BitWidth = Known.getBitWidth();
4437 
4438     // High bits are zero.
4439     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4440     break;
4441   }
4442   case AMDGPUISD::MUL_U24:
4443   case AMDGPUISD::MUL_I24: {
4444     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4445     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4446     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4447                       RHSKnown.countMinTrailingZeros();
4448     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4449     // Skip extra check if all bits are known zeros.
4450     if (TrailZ >= 32)
4451       break;
4452 
4453     // Truncate to 24 bits.
4454     LHSKnown = LHSKnown.trunc(24);
4455     RHSKnown = RHSKnown.trunc(24);
4456 
4457     if (Opc == AMDGPUISD::MUL_I24) {
4458       unsigned LHSValBits = 24 - LHSKnown.countMinSignBits();
4459       unsigned RHSValBits = 24 - RHSKnown.countMinSignBits();
4460       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4461       if (MaxValBits >= 32)
4462         break;
4463       bool LHSNegative = LHSKnown.isNegative();
4464       bool LHSNonNegative = LHSKnown.isNonNegative();
4465       bool LHSPositive = LHSKnown.isStrictlyPositive();
4466       bool RHSNegative = RHSKnown.isNegative();
4467       bool RHSNonNegative = RHSKnown.isNonNegative();
4468       bool RHSPositive = RHSKnown.isStrictlyPositive();
4469 
4470       if ((LHSNonNegative && RHSNonNegative) || (LHSNegative && RHSNegative))
4471         Known.Zero.setHighBits(32 - MaxValBits);
4472       else if ((LHSNegative && RHSPositive) || (LHSPositive && RHSNegative))
4473         Known.One.setHighBits(32 - MaxValBits);
4474     } else {
4475       unsigned LHSValBits = 24 - LHSKnown.countMinLeadingZeros();
4476       unsigned RHSValBits = 24 - RHSKnown.countMinLeadingZeros();
4477       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4478       if (MaxValBits >= 32)
4479         break;
4480       Known.Zero.setHighBits(32 - MaxValBits);
4481     }
4482     break;
4483   }
4484   case AMDGPUISD::PERM: {
4485     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4486     if (!CMask)
4487       return;
4488 
4489     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4490     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4491     unsigned Sel = CMask->getZExtValue();
4492 
4493     for (unsigned I = 0; I < 32; I += 8) {
4494       unsigned SelBits = Sel & 0xff;
4495       if (SelBits < 4) {
4496         SelBits *= 8;
4497         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4498         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4499       } else if (SelBits < 7) {
4500         SelBits = (SelBits & 3) * 8;
4501         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4502         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4503       } else if (SelBits == 0x0c) {
4504         Known.Zero |= 0xFFull << I;
4505       } else if (SelBits > 0x0c) {
4506         Known.One |= 0xFFull << I;
4507       }
4508       Sel >>= 8;
4509     }
4510     break;
4511   }
4512   case AMDGPUISD::BUFFER_LOAD_UBYTE:  {
4513     Known.Zero.setHighBits(24);
4514     break;
4515   }
4516   case AMDGPUISD::BUFFER_LOAD_USHORT: {
4517     Known.Zero.setHighBits(16);
4518     break;
4519   }
4520   case AMDGPUISD::LDS: {
4521     auto GA = cast<GlobalAddressSDNode>(Op.getOperand(0).getNode());
4522     unsigned Align = GA->getGlobal()->getAlignment();
4523 
4524     Known.Zero.setHighBits(16);
4525     if (Align)
4526       Known.Zero.setLowBits(Log2_32(Align));
4527     break;
4528   }
4529   case ISD::INTRINSIC_WO_CHAIN: {
4530     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4531     switch (IID) {
4532     case Intrinsic::amdgcn_mbcnt_lo:
4533     case Intrinsic::amdgcn_mbcnt_hi: {
4534       const GCNSubtarget &ST =
4535           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4536       // These return at most the wavefront size - 1.
4537       unsigned Size = Op.getValueType().getSizeInBits();
4538       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4539       break;
4540     }
4541     default:
4542       break;
4543     }
4544   }
4545   }
4546 }
4547 
4548 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4549     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4550     unsigned Depth) const {
4551   switch (Op.getOpcode()) {
4552   case AMDGPUISD::BFE_I32: {
4553     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4554     if (!Width)
4555       return 1;
4556 
4557     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4558     if (!isNullConstant(Op.getOperand(1)))
4559       return SignBits;
4560 
4561     // TODO: Could probably figure something out with non-0 offsets.
4562     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4563     return std::max(SignBits, Op0SignBits);
4564   }
4565 
4566   case AMDGPUISD::BFE_U32: {
4567     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4568     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4569   }
4570 
4571   case AMDGPUISD::CARRY:
4572   case AMDGPUISD::BORROW:
4573     return 31;
4574   case AMDGPUISD::BUFFER_LOAD_BYTE:
4575     return 25;
4576   case AMDGPUISD::BUFFER_LOAD_SHORT:
4577     return 17;
4578   case AMDGPUISD::BUFFER_LOAD_UBYTE:
4579     return 24;
4580   case AMDGPUISD::BUFFER_LOAD_USHORT:
4581     return 16;
4582   case AMDGPUISD::FP_TO_FP16:
4583   case AMDGPUISD::FP16_ZEXT:
4584     return 16;
4585   default:
4586     return 1;
4587   }
4588 }
4589 
4590 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4591                                                         const SelectionDAG &DAG,
4592                                                         bool SNaN,
4593                                                         unsigned Depth) const {
4594   unsigned Opcode = Op.getOpcode();
4595   switch (Opcode) {
4596   case AMDGPUISD::FMIN_LEGACY:
4597   case AMDGPUISD::FMAX_LEGACY: {
4598     if (SNaN)
4599       return true;
4600 
4601     // TODO: Can check no nans on one of the operands for each one, but which
4602     // one?
4603     return false;
4604   }
4605   case AMDGPUISD::FMUL_LEGACY:
4606   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4607     if (SNaN)
4608       return true;
4609     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4610            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4611   }
4612   case AMDGPUISD::FMED3:
4613   case AMDGPUISD::FMIN3:
4614   case AMDGPUISD::FMAX3:
4615   case AMDGPUISD::FMAD_FTZ: {
4616     if (SNaN)
4617       return true;
4618     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4619            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4620            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4621   }
4622   case AMDGPUISD::CVT_F32_UBYTE0:
4623   case AMDGPUISD::CVT_F32_UBYTE1:
4624   case AMDGPUISD::CVT_F32_UBYTE2:
4625   case AMDGPUISD::CVT_F32_UBYTE3:
4626     return true;
4627 
4628   case AMDGPUISD::RCP:
4629   case AMDGPUISD::RSQ:
4630   case AMDGPUISD::RCP_LEGACY:
4631   case AMDGPUISD::RSQ_LEGACY:
4632   case AMDGPUISD::RSQ_CLAMP: {
4633     if (SNaN)
4634       return true;
4635 
4636     // TODO: Need is known positive check.
4637     return false;
4638   }
4639   case AMDGPUISD::LDEXP:
4640   case AMDGPUISD::FRACT: {
4641     if (SNaN)
4642       return true;
4643     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4644   }
4645   case AMDGPUISD::DIV_SCALE:
4646   case AMDGPUISD::DIV_FMAS:
4647   case AMDGPUISD::DIV_FIXUP:
4648   case AMDGPUISD::TRIG_PREOP:
4649     // TODO: Refine on operands.
4650     return SNaN;
4651   case AMDGPUISD::SIN_HW:
4652   case AMDGPUISD::COS_HW: {
4653     // TODO: Need check for infinity
4654     return SNaN;
4655   }
4656   case ISD::INTRINSIC_WO_CHAIN: {
4657     unsigned IntrinsicID
4658       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4659     // TODO: Handle more intrinsics
4660     switch (IntrinsicID) {
4661     case Intrinsic::amdgcn_cubeid:
4662       return true;
4663 
4664     case Intrinsic::amdgcn_frexp_mant: {
4665       if (SNaN)
4666         return true;
4667       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4668     }
4669     case Intrinsic::amdgcn_cvt_pkrtz: {
4670       if (SNaN)
4671         return true;
4672       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4673              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4674     }
4675     case Intrinsic::amdgcn_fdot2:
4676       // TODO: Refine on operand
4677       return SNaN;
4678     default:
4679       return false;
4680     }
4681   }
4682   default:
4683     return false;
4684   }
4685 }
4686 
4687 TargetLowering::AtomicExpansionKind
4688 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4689   switch (RMW->getOperation()) {
4690   case AtomicRMWInst::Nand:
4691   case AtomicRMWInst::FAdd:
4692   case AtomicRMWInst::FSub:
4693     return AtomicExpansionKind::CmpXChg;
4694   default:
4695     return AtomicExpansionKind::None;
4696   }
4697 }
4698