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 ROTR, but not ROTL.
337   setOperationAction(ISD::ROTL, MVT::i32, Expand);
338   setOperationAction(ISD::ROTL, MVT::i64, Expand);
339   setOperationAction(ISD::ROTR, MVT::i64, Expand);
340 
341   setOperationAction(ISD::MUL, MVT::i64, Expand);
342   setOperationAction(ISD::MULHU, MVT::i64, Expand);
343   setOperationAction(ISD::MULHS, MVT::i64, Expand);
344   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
345   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
346   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
347   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
348   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
349 
350   setOperationAction(ISD::SMIN, MVT::i32, Legal);
351   setOperationAction(ISD::UMIN, MVT::i32, Legal);
352   setOperationAction(ISD::SMAX, MVT::i32, Legal);
353   setOperationAction(ISD::UMAX, MVT::i32, Legal);
354 
355   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
356   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
357   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
358   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
359 
360   static const MVT::SimpleValueType VectorIntTypes[] = {
361     MVT::v2i32, MVT::v3i32, MVT::v4i32, MVT::v5i32
362   };
363 
364   for (MVT VT : VectorIntTypes) {
365     // Expand the following operations for the current type by default.
366     setOperationAction(ISD::ADD,  VT, Expand);
367     setOperationAction(ISD::AND,  VT, Expand);
368     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
369     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
370     setOperationAction(ISD::MUL,  VT, Expand);
371     setOperationAction(ISD::MULHU, VT, Expand);
372     setOperationAction(ISD::MULHS, VT, Expand);
373     setOperationAction(ISD::OR,   VT, Expand);
374     setOperationAction(ISD::SHL,  VT, Expand);
375     setOperationAction(ISD::SRA,  VT, Expand);
376     setOperationAction(ISD::SRL,  VT, Expand);
377     setOperationAction(ISD::ROTL, VT, Expand);
378     setOperationAction(ISD::ROTR, VT, Expand);
379     setOperationAction(ISD::SUB,  VT, Expand);
380     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
381     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
382     setOperationAction(ISD::SDIV, VT, Expand);
383     setOperationAction(ISD::UDIV, VT, Expand);
384     setOperationAction(ISD::SREM, VT, Expand);
385     setOperationAction(ISD::UREM, VT, Expand);
386     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
387     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
388     setOperationAction(ISD::SDIVREM, VT, Custom);
389     setOperationAction(ISD::UDIVREM, VT, Expand);
390     setOperationAction(ISD::SELECT, VT, Expand);
391     setOperationAction(ISD::VSELECT, VT, Expand);
392     setOperationAction(ISD::SELECT_CC, VT, Expand);
393     setOperationAction(ISD::XOR,  VT, Expand);
394     setOperationAction(ISD::BSWAP, VT, Expand);
395     setOperationAction(ISD::CTPOP, VT, Expand);
396     setOperationAction(ISD::CTTZ, VT, Expand);
397     setOperationAction(ISD::CTLZ, VT, Expand);
398     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
399     setOperationAction(ISD::SETCC, VT, Expand);
400   }
401 
402   static const MVT::SimpleValueType FloatVectorTypes[] = {
403      MVT::v2f32, MVT::v3f32, MVT::v4f32, MVT::v5f32
404   };
405 
406   for (MVT VT : FloatVectorTypes) {
407     setOperationAction(ISD::FABS, VT, Expand);
408     setOperationAction(ISD::FMINNUM, VT, Expand);
409     setOperationAction(ISD::FMAXNUM, VT, Expand);
410     setOperationAction(ISD::FADD, VT, Expand);
411     setOperationAction(ISD::FCEIL, VT, Expand);
412     setOperationAction(ISD::FCOS, VT, Expand);
413     setOperationAction(ISD::FDIV, VT, Expand);
414     setOperationAction(ISD::FEXP2, VT, Expand);
415     setOperationAction(ISD::FEXP, VT, Expand);
416     setOperationAction(ISD::FLOG2, VT, Expand);
417     setOperationAction(ISD::FREM, VT, Expand);
418     setOperationAction(ISD::FLOG, VT, Expand);
419     setOperationAction(ISD::FLOG10, VT, Expand);
420     setOperationAction(ISD::FPOW, VT, Expand);
421     setOperationAction(ISD::FFLOOR, VT, Expand);
422     setOperationAction(ISD::FTRUNC, VT, Expand);
423     setOperationAction(ISD::FMUL, VT, Expand);
424     setOperationAction(ISD::FMA, VT, Expand);
425     setOperationAction(ISD::FRINT, VT, Expand);
426     setOperationAction(ISD::FNEARBYINT, VT, Expand);
427     setOperationAction(ISD::FSQRT, VT, Expand);
428     setOperationAction(ISD::FSIN, VT, Expand);
429     setOperationAction(ISD::FSUB, VT, Expand);
430     setOperationAction(ISD::FNEG, VT, Expand);
431     setOperationAction(ISD::VSELECT, VT, Expand);
432     setOperationAction(ISD::SELECT_CC, VT, Expand);
433     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
434     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
435     setOperationAction(ISD::SETCC, VT, Expand);
436     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
437   }
438 
439   // This causes using an unrolled select operation rather than expansion with
440   // bit operations. This is in general better, but the alternative using BFI
441   // instructions may be better if the select sources are SGPRs.
442   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
443   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
444 
445   setOperationAction(ISD::SELECT, MVT::v3f32, Promote);
446   AddPromotedToType(ISD::SELECT, MVT::v3f32, MVT::v3i32);
447 
448   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
449   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
450 
451   setOperationAction(ISD::SELECT, MVT::v5f32, Promote);
452   AddPromotedToType(ISD::SELECT, MVT::v5f32, MVT::v5i32);
453 
454   // There are no libcalls of any kind.
455   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
456     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
457 
458   setSchedulingPreference(Sched::RegPressure);
459   setJumpIsExpensive(true);
460 
461   // FIXME: This is only partially true. If we have to do vector compares, any
462   // SGPR pair can be a condition register. If we have a uniform condition, we
463   // are better off doing SALU operations, where there is only one SCC. For now,
464   // we don't have a way of knowing during instruction selection if a condition
465   // will be uniform and we always use vector compares. Assume we are using
466   // vector compares until that is fixed.
467   setHasMultipleConditionRegisters(true);
468 
469   setMinCmpXchgSizeInBits(32);
470   setSupportsUnalignedAtomics(false);
471 
472   PredictableSelectIsExpensive = false;
473 
474   // We want to find all load dependencies for long chains of stores to enable
475   // merging into very wide vectors. The problem is with vectors with > 4
476   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
477   // vectors are a legal type, even though we have to split the loads
478   // usually. When we can more precisely specify load legality per address
479   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
480   // smarter so that they can figure out what to do in 2 iterations without all
481   // N > 4 stores on the same chain.
482   GatherAllAliasesMaxDepth = 16;
483 
484   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
485   // about these during lowering.
486   MaxStoresPerMemcpy  = 0xffffffff;
487   MaxStoresPerMemmove = 0xffffffff;
488   MaxStoresPerMemset  = 0xffffffff;
489 
490   // The expansion for 64-bit division is enormous.
491   if (AMDGPUBypassSlowDiv)
492     addBypassSlowDiv(64, 32);
493 
494   setTargetDAGCombine(ISD::BITCAST);
495   setTargetDAGCombine(ISD::SHL);
496   setTargetDAGCombine(ISD::SRA);
497   setTargetDAGCombine(ISD::SRL);
498   setTargetDAGCombine(ISD::TRUNCATE);
499   setTargetDAGCombine(ISD::MUL);
500   setTargetDAGCombine(ISD::MULHU);
501   setTargetDAGCombine(ISD::MULHS);
502   setTargetDAGCombine(ISD::SELECT);
503   setTargetDAGCombine(ISD::SELECT_CC);
504   setTargetDAGCombine(ISD::STORE);
505   setTargetDAGCombine(ISD::FADD);
506   setTargetDAGCombine(ISD::FSUB);
507   setTargetDAGCombine(ISD::FNEG);
508   setTargetDAGCombine(ISD::FABS);
509   setTargetDAGCombine(ISD::AssertZext);
510   setTargetDAGCombine(ISD::AssertSext);
511   setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
512 }
513 
514 //===----------------------------------------------------------------------===//
515 // Target Information
516 //===----------------------------------------------------------------------===//
517 
518 LLVM_READNONE
519 static bool fnegFoldsIntoOp(unsigned Opc) {
520   switch (Opc) {
521   case ISD::FADD:
522   case ISD::FSUB:
523   case ISD::FMUL:
524   case ISD::FMA:
525   case ISD::FMAD:
526   case ISD::FMINNUM:
527   case ISD::FMAXNUM:
528   case ISD::FMINNUM_IEEE:
529   case ISD::FMAXNUM_IEEE:
530   case ISD::FSIN:
531   case ISD::FTRUNC:
532   case ISD::FRINT:
533   case ISD::FNEARBYINT:
534   case ISD::FCANONICALIZE:
535   case AMDGPUISD::RCP:
536   case AMDGPUISD::RCP_LEGACY:
537   case AMDGPUISD::RCP_IFLAG:
538   case AMDGPUISD::SIN_HW:
539   case AMDGPUISD::FMUL_LEGACY:
540   case AMDGPUISD::FMIN_LEGACY:
541   case AMDGPUISD::FMAX_LEGACY:
542   case AMDGPUISD::FMED3:
543     return true;
544   default:
545     return false;
546   }
547 }
548 
549 /// \p returns true if the operation will definitely need to use a 64-bit
550 /// encoding, and thus will use a VOP3 encoding regardless of the source
551 /// modifiers.
552 LLVM_READONLY
553 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
554   return N->getNumOperands() > 2 || VT == MVT::f64;
555 }
556 
557 // Most FP instructions support source modifiers, but this could be refined
558 // slightly.
559 LLVM_READONLY
560 static bool hasSourceMods(const SDNode *N) {
561   if (isa<MemSDNode>(N))
562     return false;
563 
564   switch (N->getOpcode()) {
565   case ISD::CopyToReg:
566   case ISD::SELECT:
567   case ISD::FDIV:
568   case ISD::FREM:
569   case ISD::INLINEASM:
570   case ISD::INLINEASM_BR:
571   case AMDGPUISD::DIV_SCALE:
572   case ISD::INTRINSIC_W_CHAIN:
573 
574   // TODO: Should really be looking at the users of the bitcast. These are
575   // problematic because bitcasts are used to legalize all stores to integer
576   // types.
577   case ISD::BITCAST:
578     return false;
579   case ISD::INTRINSIC_WO_CHAIN: {
580     switch (cast<ConstantSDNode>(N->getOperand(0))->getZExtValue()) {
581     case Intrinsic::amdgcn_interp_p1:
582     case Intrinsic::amdgcn_interp_p2:
583     case Intrinsic::amdgcn_interp_mov:
584     case Intrinsic::amdgcn_interp_p1_f16:
585     case Intrinsic::amdgcn_interp_p2_f16:
586       return false;
587     default:
588       return true;
589     }
590   }
591   default:
592     return true;
593   }
594 }
595 
596 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
597                                                  unsigned CostThreshold) {
598   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
599   // it is truly free to use a source modifier in all cases. If there are
600   // multiple users but for each one will necessitate using VOP3, there will be
601   // a code size increase. Try to avoid increasing code size unless we know it
602   // will save on the instruction count.
603   unsigned NumMayIncreaseSize = 0;
604   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
605 
606   // XXX - Should this limit number of uses to check?
607   for (const SDNode *U : N->uses()) {
608     if (!hasSourceMods(U))
609       return false;
610 
611     if (!opMustUseVOP3Encoding(U, VT)) {
612       if (++NumMayIncreaseSize > CostThreshold)
613         return false;
614     }
615   }
616 
617   return true;
618 }
619 
620 EVT AMDGPUTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
621                                               ISD::NodeType ExtendKind) const {
622   assert(!VT.isVector() && "only scalar expected");
623 
624   // Round to the next multiple of 32-bits.
625   unsigned Size = VT.getSizeInBits();
626   if (Size <= 32)
627     return MVT::i32;
628   return EVT::getIntegerVT(Context, 32 * ((Size + 31) / 32));
629 }
630 
631 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
632   return MVT::i32;
633 }
634 
635 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
636   return true;
637 }
638 
639 // The backend supports 32 and 64 bit floating point immediates.
640 // FIXME: Why are we reporting vectors of FP immediates as legal?
641 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
642                                         bool ForCodeSize) const {
643   EVT ScalarVT = VT.getScalarType();
644   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
645          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
646 }
647 
648 // We don't want to shrink f64 / f32 constants.
649 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
650   EVT ScalarVT = VT.getScalarType();
651   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
652 }
653 
654 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
655                                                  ISD::LoadExtType ExtTy,
656                                                  EVT NewVT) const {
657   // TODO: This may be worth removing. Check regression tests for diffs.
658   if (!TargetLoweringBase::shouldReduceLoadWidth(N, ExtTy, NewVT))
659     return false;
660 
661   unsigned NewSize = NewVT.getStoreSizeInBits();
662 
663   // If we are reducing to a 32-bit load or a smaller multi-dword load,
664   // this is always better.
665   if (NewSize >= 32)
666     return true;
667 
668   EVT OldVT = N->getValueType(0);
669   unsigned OldSize = OldVT.getStoreSizeInBits();
670 
671   MemSDNode *MN = cast<MemSDNode>(N);
672   unsigned AS = MN->getAddressSpace();
673   // Do not shrink an aligned scalar load to sub-dword.
674   // Scalar engine cannot do sub-dword loads.
675   if (OldSize >= 32 && NewSize < 32 && MN->getAlignment() >= 4 &&
676       (AS == AMDGPUAS::CONSTANT_ADDRESS ||
677        AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT ||
678        (isa<LoadSDNode>(N) &&
679         AS == AMDGPUAS::GLOBAL_ADDRESS && MN->isInvariant())) &&
680       AMDGPUInstrInfo::isUniformMMO(MN->getMemOperand()))
681     return false;
682 
683   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
684   // extloads, so doing one requires using a buffer_load. In cases where we
685   // still couldn't use a scalar load, using the wider load shouldn't really
686   // hurt anything.
687 
688   // If the old size already had to be an extload, there's no harm in continuing
689   // to reduce the width.
690   return (OldSize < 32);
691 }
692 
693 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy, EVT CastTy,
694                                                    const SelectionDAG &DAG,
695                                                    const MachineMemOperand &MMO) const {
696 
697   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
698 
699   if (LoadTy.getScalarType() == MVT::i32)
700     return false;
701 
702   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
703   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
704 
705   if ((LScalarSize >= CastScalarSize) && (CastScalarSize < 32))
706     return false;
707 
708   bool Fast = false;
709   return allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
710                                         CastTy, MMO, &Fast) &&
711          Fast;
712 }
713 
714 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
715 // profitable with the expansion for 64-bit since it's generally good to
716 // speculate things.
717 // FIXME: These should really have the size as a parameter.
718 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
719   return true;
720 }
721 
722 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
723   return true;
724 }
725 
726 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
727   switch (N->getOpcode()) {
728     default:
729     return false;
730     case ISD::EntryToken:
731     case ISD::TokenFactor:
732       return true;
733     case ISD::INTRINSIC_WO_CHAIN:
734     {
735       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
736       switch (IntrID) {
737         default:
738         return false;
739         case Intrinsic::amdgcn_readfirstlane:
740         case Intrinsic::amdgcn_readlane:
741           return true;
742       }
743     }
744     break;
745     case ISD::LOAD:
746     {
747       if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
748           AMDGPUAS::CONSTANT_ADDRESS_32BIT)
749         return true;
750       return false;
751     }
752     break;
753   }
754 }
755 
756 TargetLowering::NegatibleCost
757 AMDGPUTargetLowering::getNegatibleCost(SDValue Op, SelectionDAG &DAG,
758                                        bool LegalOperations, bool ForCodeSize,
759                                        unsigned Depth) const {
760   switch (Op.getOpcode()) {
761   case ISD::FMA:
762   case ISD::FMAD: {
763     // Negating a fma is not free if it has users without source mods.
764     if (!allUsesHaveSourceMods(Op.getNode()))
765       return NegatibleCost::Expensive;
766     break;
767   }
768   default:
769     break;
770   }
771 
772   return TargetLowering::getNegatibleCost(Op, DAG, LegalOperations, ForCodeSize,
773                                           Depth);
774 }
775 
776 //===---------------------------------------------------------------------===//
777 // Target Properties
778 //===---------------------------------------------------------------------===//
779 
780 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
781   assert(VT.isFloatingPoint());
782 
783   // Packed operations do not have a fabs modifier.
784   return VT == MVT::f32 || VT == MVT::f64 ||
785          (Subtarget->has16BitInsts() && VT == MVT::f16);
786 }
787 
788 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
789   assert(VT.isFloatingPoint());
790   return VT == MVT::f32 || VT == MVT::f64 ||
791          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
792          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
793 }
794 
795 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
796                                                          unsigned NumElem,
797                                                          unsigned AS) const {
798   return true;
799 }
800 
801 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
802   // There are few operations which truly have vector input operands. Any vector
803   // operation is going to involve operations on each component, and a
804   // build_vector will be a copy per element, so it always makes sense to use a
805   // build_vector input in place of the extracted element to avoid a copy into a
806   // super register.
807   //
808   // We should probably only do this if all users are extracts only, but this
809   // should be the common case.
810   return true;
811 }
812 
813 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
814   // Truncate is just accessing a subregister.
815 
816   unsigned SrcSize = Source.getSizeInBits();
817   unsigned DestSize = Dest.getSizeInBits();
818 
819   return DestSize < SrcSize && DestSize % 32 == 0 ;
820 }
821 
822 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
823   // Truncate is just accessing a subregister.
824 
825   unsigned SrcSize = Source->getScalarSizeInBits();
826   unsigned DestSize = Dest->getScalarSizeInBits();
827 
828   if (DestSize== 16 && Subtarget->has16BitInsts())
829     return SrcSize >= 32;
830 
831   return DestSize < SrcSize && DestSize % 32 == 0;
832 }
833 
834 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
835   unsigned SrcSize = Src->getScalarSizeInBits();
836   unsigned DestSize = Dest->getScalarSizeInBits();
837 
838   if (SrcSize == 16 && Subtarget->has16BitInsts())
839     return DestSize >= 32;
840 
841   return SrcSize == 32 && DestSize == 64;
842 }
843 
844 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
845   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
846   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
847   // this will enable reducing 64-bit operations the 32-bit, which is always
848   // good.
849 
850   if (Src == MVT::i16)
851     return Dest == MVT::i32 ||Dest == MVT::i64 ;
852 
853   return Src == MVT::i32 && Dest == MVT::i64;
854 }
855 
856 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
857   return isZExtFree(Val.getValueType(), VT2);
858 }
859 
860 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
861   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
862   // limited number of native 64-bit operations. Shrinking an operation to fit
863   // in a single 32-bit register should always be helpful. As currently used,
864   // this is much less general than the name suggests, and is only used in
865   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
866   // not profitable, and may actually be harmful.
867   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
868 }
869 
870 //===---------------------------------------------------------------------===//
871 // TargetLowering Callbacks
872 //===---------------------------------------------------------------------===//
873 
874 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
875                                                   bool IsVarArg) {
876   switch (CC) {
877   case CallingConv::AMDGPU_VS:
878   case CallingConv::AMDGPU_GS:
879   case CallingConv::AMDGPU_PS:
880   case CallingConv::AMDGPU_CS:
881   case CallingConv::AMDGPU_HS:
882   case CallingConv::AMDGPU_ES:
883   case CallingConv::AMDGPU_LS:
884     return CC_AMDGPU;
885   case CallingConv::C:
886   case CallingConv::Fast:
887   case CallingConv::Cold:
888     return CC_AMDGPU_Func;
889   case CallingConv::AMDGPU_KERNEL:
890   case CallingConv::SPIR_KERNEL:
891   default:
892     report_fatal_error("Unsupported calling convention for call");
893   }
894 }
895 
896 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
897                                                     bool IsVarArg) {
898   switch (CC) {
899   case CallingConv::AMDGPU_KERNEL:
900   case CallingConv::SPIR_KERNEL:
901     llvm_unreachable("kernels should not be handled here");
902   case CallingConv::AMDGPU_VS:
903   case CallingConv::AMDGPU_GS:
904   case CallingConv::AMDGPU_PS:
905   case CallingConv::AMDGPU_CS:
906   case CallingConv::AMDGPU_HS:
907   case CallingConv::AMDGPU_ES:
908   case CallingConv::AMDGPU_LS:
909     return RetCC_SI_Shader;
910   case CallingConv::C:
911   case CallingConv::Fast:
912   case CallingConv::Cold:
913     return RetCC_AMDGPU_Func;
914   default:
915     report_fatal_error("Unsupported calling convention.");
916   }
917 }
918 
919 /// The SelectionDAGBuilder will automatically promote function arguments
920 /// with illegal types.  However, this does not work for the AMDGPU targets
921 /// since the function arguments are stored in memory as these illegal types.
922 /// In order to handle this properly we need to get the original types sizes
923 /// from the LLVM IR Function and fixup the ISD:InputArg values before
924 /// passing them to AnalyzeFormalArguments()
925 
926 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
927 /// input values across multiple registers.  Each item in the Ins array
928 /// represents a single value that will be stored in registers.  Ins[x].VT is
929 /// the value type of the value that will be stored in the register, so
930 /// whatever SDNode we lower the argument to needs to be this type.
931 ///
932 /// In order to correctly lower the arguments we need to know the size of each
933 /// argument.  Since Ins[x].VT gives us the size of the register that will
934 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
935 /// for the orignal function argument so that we can deduce the correct memory
936 /// type to use for Ins[x].  In most cases the correct memory type will be
937 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
938 /// we have a kernel argument of type v8i8, this argument will be split into
939 /// 8 parts and each part will be represented by its own item in the Ins array.
940 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
941 /// the argument before it was split.  From this, we deduce that the memory type
942 /// for each individual part is i8.  We pass the memory type as LocVT to the
943 /// calling convention analysis function and the register type (Ins[x].VT) as
944 /// the ValVT.
945 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
946   CCState &State,
947   const SmallVectorImpl<ISD::InputArg> &Ins) const {
948   const MachineFunction &MF = State.getMachineFunction();
949   const Function &Fn = MF.getFunction();
950   LLVMContext &Ctx = Fn.getParent()->getContext();
951   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
952   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
953   CallingConv::ID CC = Fn.getCallingConv();
954 
955   unsigned MaxAlign = 1;
956   uint64_t ExplicitArgOffset = 0;
957   const DataLayout &DL = Fn.getParent()->getDataLayout();
958 
959   unsigned InIndex = 0;
960 
961   for (const Argument &Arg : Fn.args()) {
962     Type *BaseArgTy = Arg.getType();
963     unsigned Align = DL.getABITypeAlignment(BaseArgTy);
964     MaxAlign = std::max(Align, MaxAlign);
965     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
966 
967     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Align) + ExplicitOffset;
968     ExplicitArgOffset = alignTo(ExplicitArgOffset, Align) + AllocSize;
969 
970     // We're basically throwing away everything passed into us and starting over
971     // to get accurate in-memory offsets. The "PartOffset" is completely useless
972     // to us as computed in Ins.
973     //
974     // We also need to figure out what type legalization is trying to do to get
975     // the correct memory offsets.
976 
977     SmallVector<EVT, 16> ValueVTs;
978     SmallVector<uint64_t, 16> Offsets;
979     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
980 
981     for (unsigned Value = 0, NumValues = ValueVTs.size();
982          Value != NumValues; ++Value) {
983       uint64_t BasePartOffset = Offsets[Value];
984 
985       EVT ArgVT = ValueVTs[Value];
986       EVT MemVT = ArgVT;
987       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
988       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
989 
990       if (NumRegs == 1) {
991         // This argument is not split, so the IR type is the memory type.
992         if (ArgVT.isExtended()) {
993           // We have an extended type, like i24, so we should just use the
994           // register type.
995           MemVT = RegisterVT;
996         } else {
997           MemVT = ArgVT;
998         }
999       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
1000                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
1001         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
1002         // We have a vector value which has been split into a vector with
1003         // the same scalar type, but fewer elements.  This should handle
1004         // all the floating-point vector types.
1005         MemVT = RegisterVT;
1006       } else if (ArgVT.isVector() &&
1007                  ArgVT.getVectorNumElements() == NumRegs) {
1008         // This arg has been split so that each element is stored in a separate
1009         // register.
1010         MemVT = ArgVT.getScalarType();
1011       } else if (ArgVT.isExtended()) {
1012         // We have an extended type, like i65.
1013         MemVT = RegisterVT;
1014       } else {
1015         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
1016         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
1017         if (RegisterVT.isInteger()) {
1018           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1019         } else if (RegisterVT.isVector()) {
1020           assert(!RegisterVT.getScalarType().isFloatingPoint());
1021           unsigned NumElements = RegisterVT.getVectorNumElements();
1022           assert(MemoryBits % NumElements == 0);
1023           // This vector type has been split into another vector type with
1024           // a different elements size.
1025           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1026                                            MemoryBits / NumElements);
1027           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1028         } else {
1029           llvm_unreachable("cannot deduce memory type.");
1030         }
1031       }
1032 
1033       // Convert one element vectors to scalar.
1034       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1035         MemVT = MemVT.getScalarType();
1036 
1037       // Round up vec3/vec5 argument.
1038       if (MemVT.isVector() && !MemVT.isPow2VectorType()) {
1039         assert(MemVT.getVectorNumElements() == 3 ||
1040                MemVT.getVectorNumElements() == 5);
1041         MemVT = MemVT.getPow2VectorType(State.getContext());
1042       } else if (!MemVT.isSimple() && !MemVT.isVector()) {
1043         MemVT = MemVT.getRoundIntegerType(State.getContext());
1044       }
1045 
1046       unsigned PartOffset = 0;
1047       for (unsigned i = 0; i != NumRegs; ++i) {
1048         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1049                                                BasePartOffset + PartOffset,
1050                                                MemVT.getSimpleVT(),
1051                                                CCValAssign::Full));
1052         PartOffset += MemVT.getStoreSize();
1053       }
1054     }
1055   }
1056 }
1057 
1058 SDValue AMDGPUTargetLowering::LowerReturn(
1059   SDValue Chain, CallingConv::ID CallConv,
1060   bool isVarArg,
1061   const SmallVectorImpl<ISD::OutputArg> &Outs,
1062   const SmallVectorImpl<SDValue> &OutVals,
1063   const SDLoc &DL, SelectionDAG &DAG) const {
1064   // FIXME: Fails for r600 tests
1065   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1066   // "wave terminate should not have return values");
1067   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1068 }
1069 
1070 //===---------------------------------------------------------------------===//
1071 // Target specific lowering
1072 //===---------------------------------------------------------------------===//
1073 
1074 /// Selects the correct CCAssignFn for a given CallingConvention value.
1075 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1076                                                     bool IsVarArg) {
1077   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1078 }
1079 
1080 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1081                                                       bool IsVarArg) {
1082   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1083 }
1084 
1085 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1086                                                   SelectionDAG &DAG,
1087                                                   MachineFrameInfo &MFI,
1088                                                   int ClobberedFI) const {
1089   SmallVector<SDValue, 8> ArgChains;
1090   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1091   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1092 
1093   // Include the original chain at the beginning of the list. When this is
1094   // used by target LowerCall hooks, this helps legalize find the
1095   // CALLSEQ_BEGIN node.
1096   ArgChains.push_back(Chain);
1097 
1098   // Add a chain value for each stack argument corresponding
1099   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1100                             UE = DAG.getEntryNode().getNode()->use_end();
1101        U != UE; ++U) {
1102     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1103       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1104         if (FI->getIndex() < 0) {
1105           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1106           int64_t InLastByte = InFirstByte;
1107           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1108 
1109           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1110               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1111             ArgChains.push_back(SDValue(L, 1));
1112         }
1113       }
1114     }
1115   }
1116 
1117   // Build a tokenfactor for all the chains.
1118   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1119 }
1120 
1121 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1122                                                  SmallVectorImpl<SDValue> &InVals,
1123                                                  StringRef Reason) const {
1124   SDValue Callee = CLI.Callee;
1125   SelectionDAG &DAG = CLI.DAG;
1126 
1127   const Function &Fn = DAG.getMachineFunction().getFunction();
1128 
1129   StringRef FuncName("<unknown>");
1130 
1131   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1132     FuncName = G->getSymbol();
1133   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1134     FuncName = G->getGlobal()->getName();
1135 
1136   DiagnosticInfoUnsupported NoCalls(
1137     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1138   DAG.getContext()->diagnose(NoCalls);
1139 
1140   if (!CLI.IsTailCall) {
1141     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1142       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1143   }
1144 
1145   return DAG.getEntryNode();
1146 }
1147 
1148 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1149                                         SmallVectorImpl<SDValue> &InVals) const {
1150   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1151 }
1152 
1153 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1154                                                       SelectionDAG &DAG) const {
1155   const Function &Fn = DAG.getMachineFunction().getFunction();
1156 
1157   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1158                                             SDLoc(Op).getDebugLoc());
1159   DAG.getContext()->diagnose(NoDynamicAlloca);
1160   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1161   return DAG.getMergeValues(Ops, SDLoc());
1162 }
1163 
1164 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1165                                              SelectionDAG &DAG) const {
1166   switch (Op.getOpcode()) {
1167   default:
1168     Op->print(errs(), &DAG);
1169     llvm_unreachable("Custom lowering code for this"
1170                      "instruction is not implemented yet!");
1171     break;
1172   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1173   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1174   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1175   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1176   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1177   case ISD::FREM: return LowerFREM(Op, DAG);
1178   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1179   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1180   case ISD::FRINT: return LowerFRINT(Op, DAG);
1181   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1182   case ISD::FROUND: return LowerFROUND(Op, DAG);
1183   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1184   case ISD::FLOG:
1185     return LowerFLOG(Op, DAG, 1.0F / numbers::log2ef);
1186   case ISD::FLOG10:
1187     return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
1188   case ISD::FEXP:
1189     return lowerFEXP(Op, DAG);
1190   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1191   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1192   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1193   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1194   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1195   case ISD::CTTZ:
1196   case ISD::CTTZ_ZERO_UNDEF:
1197   case ISD::CTLZ:
1198   case ISD::CTLZ_ZERO_UNDEF:
1199     return LowerCTLZ_CTTZ(Op, DAG);
1200   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1201   }
1202   return Op;
1203 }
1204 
1205 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1206                                               SmallVectorImpl<SDValue> &Results,
1207                                               SelectionDAG &DAG) const {
1208   switch (N->getOpcode()) {
1209   case ISD::SIGN_EXTEND_INREG:
1210     // Different parts of legalization seem to interpret which type of
1211     // sign_extend_inreg is the one to check for custom lowering. The extended
1212     // from type is what really matters, but some places check for custom
1213     // lowering of the result type. This results in trying to use
1214     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1215     // nothing here and let the illegal result integer be handled normally.
1216     return;
1217   default:
1218     return;
1219   }
1220 }
1221 
1222 bool AMDGPUTargetLowering::hasDefinedInitializer(const GlobalValue *GV) {
1223   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1224   if (!GVar || !GVar->hasInitializer())
1225     return false;
1226 
1227   return !isa<UndefValue>(GVar->getInitializer());
1228 }
1229 
1230 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1231                                                  SDValue Op,
1232                                                  SelectionDAG &DAG) const {
1233 
1234   const DataLayout &DL = DAG.getDataLayout();
1235   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1236   const GlobalValue *GV = G->getGlobal();
1237 
1238   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1239       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1240     if (!MFI->isEntryFunction()) {
1241       const Function &Fn = DAG.getMachineFunction().getFunction();
1242       DiagnosticInfoUnsupported BadLDSDecl(
1243         Fn, "local memory global used by non-kernel function", SDLoc(Op).getDebugLoc());
1244       DAG.getContext()->diagnose(BadLDSDecl);
1245     }
1246 
1247     // XXX: What does the value of G->getOffset() mean?
1248     assert(G->getOffset() == 0 &&
1249          "Do not know what to do with an non-zero offset");
1250 
1251     // TODO: We could emit code to handle the initialization somewhere.
1252     if (!hasDefinedInitializer(GV)) {
1253       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1254       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1255     }
1256   }
1257 
1258   const Function &Fn = DAG.getMachineFunction().getFunction();
1259   DiagnosticInfoUnsupported BadInit(
1260       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1261   DAG.getContext()->diagnose(BadInit);
1262   return SDValue();
1263 }
1264 
1265 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1266                                                   SelectionDAG &DAG) const {
1267   SmallVector<SDValue, 8> Args;
1268 
1269   EVT VT = Op.getValueType();
1270   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1271     SDLoc SL(Op);
1272     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1273     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1274 
1275     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1276     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1277   }
1278 
1279   for (const SDUse &U : Op->ops())
1280     DAG.ExtractVectorElements(U.get(), Args);
1281 
1282   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1283 }
1284 
1285 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1286                                                      SelectionDAG &DAG) const {
1287 
1288   SmallVector<SDValue, 8> Args;
1289   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1290   EVT VT = Op.getValueType();
1291   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1292                             VT.getVectorNumElements());
1293 
1294   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1295 }
1296 
1297 /// Generate Min/Max node
1298 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1299                                                    SDValue LHS, SDValue RHS,
1300                                                    SDValue True, SDValue False,
1301                                                    SDValue CC,
1302                                                    DAGCombinerInfo &DCI) const {
1303   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1304     return SDValue();
1305 
1306   SelectionDAG &DAG = DCI.DAG;
1307   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1308   switch (CCOpcode) {
1309   case ISD::SETOEQ:
1310   case ISD::SETONE:
1311   case ISD::SETUNE:
1312   case ISD::SETNE:
1313   case ISD::SETUEQ:
1314   case ISD::SETEQ:
1315   case ISD::SETFALSE:
1316   case ISD::SETFALSE2:
1317   case ISD::SETTRUE:
1318   case ISD::SETTRUE2:
1319   case ISD::SETUO:
1320   case ISD::SETO:
1321     break;
1322   case ISD::SETULE:
1323   case ISD::SETULT: {
1324     if (LHS == True)
1325       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1326     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1327   }
1328   case ISD::SETOLE:
1329   case ISD::SETOLT:
1330   case ISD::SETLE:
1331   case ISD::SETLT: {
1332     // Ordered. Assume ordered for undefined.
1333 
1334     // Only do this after legalization to avoid interfering with other combines
1335     // which might occur.
1336     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1337         !DCI.isCalledByLegalizer())
1338       return SDValue();
1339 
1340     // We need to permute the operands to get the correct NaN behavior. The
1341     // selected operand is the second one based on the failing compare with NaN,
1342     // so permute it based on the compare type the hardware uses.
1343     if (LHS == True)
1344       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1345     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1346   }
1347   case ISD::SETUGE:
1348   case ISD::SETUGT: {
1349     if (LHS == True)
1350       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1351     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1352   }
1353   case ISD::SETGT:
1354   case ISD::SETGE:
1355   case ISD::SETOGE:
1356   case ISD::SETOGT: {
1357     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1358         !DCI.isCalledByLegalizer())
1359       return SDValue();
1360 
1361     if (LHS == True)
1362       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1363     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1364   }
1365   case ISD::SETCC_INVALID:
1366     llvm_unreachable("Invalid setcc condcode!");
1367   }
1368   return SDValue();
1369 }
1370 
1371 std::pair<SDValue, SDValue>
1372 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1373   SDLoc SL(Op);
1374 
1375   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1376 
1377   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1378   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1379 
1380   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1381   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1382 
1383   return std::make_pair(Lo, Hi);
1384 }
1385 
1386 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1387   SDLoc SL(Op);
1388 
1389   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1390   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1391   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1392 }
1393 
1394 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1395   SDLoc SL(Op);
1396 
1397   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1398   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1399   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1400 }
1401 
1402 // Split a vector type into two parts. The first part is a power of two vector.
1403 // The second part is whatever is left over, and is a scalar if it would
1404 // otherwise be a 1-vector.
1405 std::pair<EVT, EVT>
1406 AMDGPUTargetLowering::getSplitDestVTs(const EVT &VT, SelectionDAG &DAG) const {
1407   EVT LoVT, HiVT;
1408   EVT EltVT = VT.getVectorElementType();
1409   unsigned NumElts = VT.getVectorNumElements();
1410   unsigned LoNumElts = PowerOf2Ceil((NumElts + 1) / 2);
1411   LoVT = EVT::getVectorVT(*DAG.getContext(), EltVT, LoNumElts);
1412   HiVT = NumElts - LoNumElts == 1
1413              ? EltVT
1414              : EVT::getVectorVT(*DAG.getContext(), EltVT, NumElts - LoNumElts);
1415   return std::make_pair(LoVT, HiVT);
1416 }
1417 
1418 // Split a vector value into two parts of types LoVT and HiVT. HiVT could be
1419 // scalar.
1420 std::pair<SDValue, SDValue>
1421 AMDGPUTargetLowering::splitVector(const SDValue &N, const SDLoc &DL,
1422                                   const EVT &LoVT, const EVT &HiVT,
1423                                   SelectionDAG &DAG) const {
1424   assert(LoVT.getVectorNumElements() +
1425                  (HiVT.isVector() ? HiVT.getVectorNumElements() : 1) <=
1426              N.getValueType().getVectorNumElements() &&
1427          "More vector elements requested than available!");
1428   SDValue Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, LoVT, N,
1429                            DAG.getVectorIdxConstant(0, DL));
1430   SDValue Hi = DAG.getNode(
1431       HiVT.isVector() ? ISD::EXTRACT_SUBVECTOR : ISD::EXTRACT_VECTOR_ELT, DL,
1432       HiVT, N, DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), DL));
1433   return std::make_pair(Lo, Hi);
1434 }
1435 
1436 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1437                                               SelectionDAG &DAG) const {
1438   LoadSDNode *Load = cast<LoadSDNode>(Op);
1439   EVT VT = Op.getValueType();
1440   SDLoc SL(Op);
1441 
1442 
1443   // If this is a 2 element vector, we really want to scalarize and not create
1444   // weird 1 element vectors.
1445   if (VT.getVectorNumElements() == 2) {
1446     SDValue Ops[2];
1447     std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(Load, DAG);
1448     return DAG.getMergeValues(Ops, SL);
1449   }
1450 
1451   SDValue BasePtr = Load->getBasePtr();
1452   EVT MemVT = Load->getMemoryVT();
1453 
1454   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1455 
1456   EVT LoVT, HiVT;
1457   EVT LoMemVT, HiMemVT;
1458   SDValue Lo, Hi;
1459 
1460   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1461   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1462   std::tie(Lo, Hi) = splitVector(Op, SL, LoVT, HiVT, DAG);
1463 
1464   unsigned Size = LoMemVT.getStoreSize();
1465   unsigned BaseAlign = Load->getAlignment();
1466   unsigned HiAlign = MinAlign(BaseAlign, Size);
1467 
1468   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1469                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1470                                   BaseAlign, Load->getMemOperand()->getFlags());
1471   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1472   SDValue HiLoad =
1473       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1474                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1475                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1476 
1477   SDValue Join;
1478   if (LoVT == HiVT) {
1479     // This is the case that the vector is power of two so was evenly split.
1480     Join = DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad);
1481   } else {
1482     Join = DAG.getNode(ISD::INSERT_SUBVECTOR, SL, VT, DAG.getUNDEF(VT), LoLoad,
1483                        DAG.getVectorIdxConstant(0, SL));
1484     Join = DAG.getNode(
1485         HiVT.isVector() ? ISD::INSERT_SUBVECTOR : ISD::INSERT_VECTOR_ELT, SL,
1486         VT, Join, HiLoad,
1487         DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), SL));
1488   }
1489 
1490   SDValue Ops[] = {Join, DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1491                                      LoLoad.getValue(1), HiLoad.getValue(1))};
1492 
1493   return DAG.getMergeValues(Ops, SL);
1494 }
1495 
1496 // Widen a vector load from vec3 to vec4.
1497 SDValue AMDGPUTargetLowering::WidenVectorLoad(SDValue Op,
1498                                               SelectionDAG &DAG) const {
1499   LoadSDNode *Load = cast<LoadSDNode>(Op);
1500   EVT VT = Op.getValueType();
1501   assert(VT.getVectorNumElements() == 3);
1502   SDValue BasePtr = Load->getBasePtr();
1503   EVT MemVT = Load->getMemoryVT();
1504   SDLoc SL(Op);
1505   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1506   unsigned BaseAlign = Load->getAlignment();
1507 
1508   EVT WideVT =
1509       EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(), 4);
1510   EVT WideMemVT =
1511       EVT::getVectorVT(*DAG.getContext(), MemVT.getVectorElementType(), 4);
1512   SDValue WideLoad = DAG.getExtLoad(
1513       Load->getExtensionType(), SL, WideVT, Load->getChain(), BasePtr, SrcValue,
1514       WideMemVT, BaseAlign, Load->getMemOperand()->getFlags());
1515   return DAG.getMergeValues(
1516       {DAG.getNode(ISD::EXTRACT_SUBVECTOR, SL, VT, WideLoad,
1517                    DAG.getVectorIdxConstant(0, SL)),
1518        WideLoad.getValue(1)},
1519       SL);
1520 }
1521 
1522 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1523                                                SelectionDAG &DAG) const {
1524   StoreSDNode *Store = cast<StoreSDNode>(Op);
1525   SDValue Val = Store->getValue();
1526   EVT VT = Val.getValueType();
1527 
1528   // If this is a 2 element vector, we really want to scalarize and not create
1529   // weird 1 element vectors.
1530   if (VT.getVectorNumElements() == 2)
1531     return scalarizeVectorStore(Store, DAG);
1532 
1533   EVT MemVT = Store->getMemoryVT();
1534   SDValue Chain = Store->getChain();
1535   SDValue BasePtr = Store->getBasePtr();
1536   SDLoc SL(Op);
1537 
1538   EVT LoVT, HiVT;
1539   EVT LoMemVT, HiMemVT;
1540   SDValue Lo, Hi;
1541 
1542   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1543   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1544   std::tie(Lo, Hi) = splitVector(Val, SL, LoVT, HiVT, DAG);
1545 
1546   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1547 
1548   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1549   unsigned BaseAlign = Store->getAlignment();
1550   unsigned Size = LoMemVT.getStoreSize();
1551   unsigned HiAlign = MinAlign(BaseAlign, Size);
1552 
1553   SDValue LoStore =
1554       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1555                         Store->getMemOperand()->getFlags());
1556   SDValue HiStore =
1557       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1558                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1559 
1560   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1561 }
1562 
1563 // This is a shortcut for integer division because we have fast i32<->f32
1564 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1565 // float is enough to accurately represent up to a 24-bit signed integer.
1566 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1567                                             bool Sign) const {
1568   SDLoc DL(Op);
1569   EVT VT = Op.getValueType();
1570   SDValue LHS = Op.getOperand(0);
1571   SDValue RHS = Op.getOperand(1);
1572   MVT IntVT = MVT::i32;
1573   MVT FltVT = MVT::f32;
1574 
1575   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1576   if (LHSSignBits < 9)
1577     return SDValue();
1578 
1579   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1580   if (RHSSignBits < 9)
1581     return SDValue();
1582 
1583   unsigned BitSize = VT.getSizeInBits();
1584   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1585   unsigned DivBits = BitSize - SignBits;
1586   if (Sign)
1587     ++DivBits;
1588 
1589   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1590   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1591 
1592   SDValue jq = DAG.getConstant(1, DL, IntVT);
1593 
1594   if (Sign) {
1595     // char|short jq = ia ^ ib;
1596     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1597 
1598     // jq = jq >> (bitsize - 2)
1599     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1600                      DAG.getConstant(BitSize - 2, DL, VT));
1601 
1602     // jq = jq | 0x1
1603     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1604   }
1605 
1606   // int ia = (int)LHS;
1607   SDValue ia = LHS;
1608 
1609   // int ib, (int)RHS;
1610   SDValue ib = RHS;
1611 
1612   // float fa = (float)ia;
1613   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1614 
1615   // float fb = (float)ib;
1616   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1617 
1618   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1619                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1620 
1621   // fq = trunc(fq);
1622   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1623 
1624   // float fqneg = -fq;
1625   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1626 
1627   MachineFunction &MF = DAG.getMachineFunction();
1628   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
1629 
1630   // float fr = mad(fqneg, fb, fa);
1631   unsigned OpCode = MFI->getMode().allFP32Denormals() ?
1632                     (unsigned)AMDGPUISD::FMAD_FTZ :
1633                     (unsigned)ISD::FMAD;
1634   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1635 
1636   // int iq = (int)fq;
1637   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1638 
1639   // fr = fabs(fr);
1640   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1641 
1642   // fb = fabs(fb);
1643   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1644 
1645   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1646 
1647   // int cv = fr >= fb;
1648   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1649 
1650   // jq = (cv ? jq : 0);
1651   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1652 
1653   // dst = iq + jq;
1654   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1655 
1656   // Rem needs compensation, it's easier to recompute it
1657   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1658   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1659 
1660   // Truncate to number of bits this divide really is.
1661   if (Sign) {
1662     SDValue InRegSize
1663       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1664     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1665     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1666   } else {
1667     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1668     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1669     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1670   }
1671 
1672   return DAG.getMergeValues({ Div, Rem }, DL);
1673 }
1674 
1675 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1676                                       SelectionDAG &DAG,
1677                                       SmallVectorImpl<SDValue> &Results) const {
1678   SDLoc DL(Op);
1679   EVT VT = Op.getValueType();
1680 
1681   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1682 
1683   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1684 
1685   SDValue One = DAG.getConstant(1, DL, HalfVT);
1686   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1687 
1688   //HiLo split
1689   SDValue LHS = Op.getOperand(0);
1690   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1691   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1692 
1693   SDValue RHS = Op.getOperand(1);
1694   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1695   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1696 
1697   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1698       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1699 
1700     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1701                               LHS_Lo, RHS_Lo);
1702 
1703     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1704     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1705 
1706     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1707     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1708     return;
1709   }
1710 
1711   if (isTypeLegal(MVT::i64)) {
1712     MachineFunction &MF = DAG.getMachineFunction();
1713     const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1714 
1715     // Compute denominator reciprocal.
1716     unsigned FMAD = MFI->getMode().allFP32Denormals() ?
1717                     (unsigned)AMDGPUISD::FMAD_FTZ :
1718                     (unsigned)ISD::FMAD;
1719 
1720     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1721     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1722     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1723       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1724       Cvt_Lo);
1725     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1726     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1727       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1728     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1729       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1730     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1731     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1732       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1733       Mul1);
1734     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1735     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1736     SDValue Rcp64 = DAG.getBitcast(VT,
1737                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1738 
1739     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1740     SDValue One64  = DAG.getConstant(1, DL, VT);
1741     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1742     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1743 
1744     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1745     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1746     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1747     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1748                                     Zero);
1749     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1750                                     One);
1751 
1752     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1753                                   Mulhi1_Lo, Zero1);
1754     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1755                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1756     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1757     SDValue Add1 = DAG.getBitcast(VT,
1758                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1759 
1760     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1761     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1762     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1763                                     Zero);
1764     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1765                                     One);
1766 
1767     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1768                                   Mulhi2_Lo, Zero1);
1769     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1770                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1771     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1772                                   Zero, Add2_Lo.getValue(1));
1773     SDValue Add2 = DAG.getBitcast(VT,
1774                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1775     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1776 
1777     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1778 
1779     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1780     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1781     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1782                                   Mul3_Lo, Zero1);
1783     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1784                                   Mul3_Hi, Sub1_Lo.getValue(1));
1785     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1786     SDValue Sub1 = DAG.getBitcast(VT,
1787                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1788 
1789     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1790     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1791                                  ISD::SETUGE);
1792     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1793                                  ISD::SETUGE);
1794     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1795 
1796     // TODO: Here and below portions of the code can be enclosed into if/endif.
1797     // Currently control flow is unconditional and we have 4 selects after
1798     // potential endif to substitute PHIs.
1799 
1800     // if C3 != 0 ...
1801     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1802                                   RHS_Lo, Zero1);
1803     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1804                                   RHS_Hi, Sub1_Lo.getValue(1));
1805     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1806                                   Zero, Sub2_Lo.getValue(1));
1807     SDValue Sub2 = DAG.getBitcast(VT,
1808                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1809 
1810     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1811 
1812     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1813                                  ISD::SETUGE);
1814     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1815                                  ISD::SETUGE);
1816     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1817 
1818     // if (C6 != 0)
1819     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1820 
1821     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1822                                   RHS_Lo, Zero1);
1823     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1824                                   RHS_Hi, Sub2_Lo.getValue(1));
1825     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1826                                   Zero, Sub3_Lo.getValue(1));
1827     SDValue Sub3 = DAG.getBitcast(VT,
1828                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1829 
1830     // endif C6
1831     // endif C3
1832 
1833     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1834     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1835 
1836     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1837     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1838 
1839     Results.push_back(Div);
1840     Results.push_back(Rem);
1841 
1842     return;
1843   }
1844 
1845   // r600 expandion.
1846   // Get Speculative values
1847   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1848   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1849 
1850   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1851   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1852   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1853 
1854   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1855   SDValue DIV_Lo = Zero;
1856 
1857   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1858 
1859   for (unsigned i = 0; i < halfBitWidth; ++i) {
1860     const unsigned bitPos = halfBitWidth - i - 1;
1861     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1862     // Get value of high bit
1863     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1864     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1865     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1866 
1867     // Shift
1868     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1869     // Add LHS high bit
1870     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1871 
1872     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1873     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1874 
1875     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1876 
1877     // Update REM
1878     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1879     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1880   }
1881 
1882   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1883   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1884   Results.push_back(DIV);
1885   Results.push_back(REM);
1886 }
1887 
1888 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1889                                            SelectionDAG &DAG) const {
1890   SDLoc DL(Op);
1891   EVT VT = Op.getValueType();
1892 
1893   if (VT == MVT::i64) {
1894     SmallVector<SDValue, 2> Results;
1895     LowerUDIVREM64(Op, DAG, Results);
1896     return DAG.getMergeValues(Results, DL);
1897   }
1898 
1899   if (VT == MVT::i32) {
1900     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1901       return Res;
1902   }
1903 
1904   SDValue Num = Op.getOperand(0);
1905   SDValue Den = Op.getOperand(1);
1906 
1907   // RCP =  URECIP(Den) = 2^32 / Den + e
1908   // e is rounding error.
1909   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1910 
1911   // RCP_LO = mul(RCP, Den) */
1912   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1913 
1914   // RCP_HI = mulhu (RCP, Den) */
1915   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1916 
1917   // NEG_RCP_LO = -RCP_LO
1918   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1919                                                      RCP_LO);
1920 
1921   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1922   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1923                                            NEG_RCP_LO, RCP_LO,
1924                                            ISD::SETEQ);
1925   // Calculate the rounding error from the URECIP instruction
1926   // E = mulhu(ABS_RCP_LO, RCP)
1927   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1928 
1929   // RCP_A_E = RCP + E
1930   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1931 
1932   // RCP_S_E = RCP - E
1933   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1934 
1935   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1936   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1937                                      RCP_A_E, RCP_S_E,
1938                                      ISD::SETEQ);
1939   // Quotient = mulhu(Tmp0, Num)
1940   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1941 
1942   // Num_S_Remainder = Quotient * Den
1943   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1944 
1945   // Remainder = Num - Num_S_Remainder
1946   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1947 
1948   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1949   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1950                                                  DAG.getConstant(-1, DL, VT),
1951                                                  DAG.getConstant(0, DL, VT),
1952                                                  ISD::SETUGE);
1953   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1954   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1955                                                   Num_S_Remainder,
1956                                                   DAG.getConstant(-1, DL, VT),
1957                                                   DAG.getConstant(0, DL, VT),
1958                                                   ISD::SETUGE);
1959   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1960   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1961                                                Remainder_GE_Zero);
1962 
1963   // Calculate Division result:
1964 
1965   // Quotient_A_One = Quotient + 1
1966   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1967                                        DAG.getConstant(1, DL, VT));
1968 
1969   // Quotient_S_One = Quotient - 1
1970   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1971                                        DAG.getConstant(1, DL, VT));
1972 
1973   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1974   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1975                                      Quotient, Quotient_A_One, ISD::SETEQ);
1976 
1977   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1978   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1979                             Quotient_S_One, Div, ISD::SETEQ);
1980 
1981   // Calculate Rem result:
1982 
1983   // Remainder_S_Den = Remainder - Den
1984   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1985 
1986   // Remainder_A_Den = Remainder + Den
1987   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1988 
1989   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1990   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1991                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1992 
1993   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1994   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1995                             Remainder_A_Den, Rem, ISD::SETEQ);
1996   SDValue Ops[2] = {
1997     Div,
1998     Rem
1999   };
2000   return DAG.getMergeValues(Ops, DL);
2001 }
2002 
2003 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
2004                                            SelectionDAG &DAG) const {
2005   SDLoc DL(Op);
2006   EVT VT = Op.getValueType();
2007 
2008   SDValue LHS = Op.getOperand(0);
2009   SDValue RHS = Op.getOperand(1);
2010 
2011   SDValue Zero = DAG.getConstant(0, DL, VT);
2012   SDValue NegOne = DAG.getConstant(-1, DL, VT);
2013 
2014   if (VT == MVT::i32) {
2015     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
2016       return Res;
2017   }
2018 
2019   if (VT == MVT::i64 &&
2020       DAG.ComputeNumSignBits(LHS) > 32 &&
2021       DAG.ComputeNumSignBits(RHS) > 32) {
2022     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
2023 
2024     //HiLo split
2025     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
2026     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
2027     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
2028                                  LHS_Lo, RHS_Lo);
2029     SDValue Res[2] = {
2030       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
2031       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
2032     };
2033     return DAG.getMergeValues(Res, DL);
2034   }
2035 
2036   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
2037   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
2038   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
2039   SDValue RSign = LHSign; // Remainder sign is the same as LHS
2040 
2041   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
2042   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
2043 
2044   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
2045   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
2046 
2047   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
2048   SDValue Rem = Div.getValue(1);
2049 
2050   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
2051   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
2052 
2053   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
2054   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
2055 
2056   SDValue Res[2] = {
2057     Div,
2058     Rem
2059   };
2060   return DAG.getMergeValues(Res, DL);
2061 }
2062 
2063 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2064 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2065   SDLoc SL(Op);
2066   EVT VT = Op.getValueType();
2067   SDValue X = Op.getOperand(0);
2068   SDValue Y = Op.getOperand(1);
2069 
2070   // TODO: Should this propagate fast-math-flags?
2071 
2072   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2073   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2074   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2075 
2076   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2077 }
2078 
2079 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2080   SDLoc SL(Op);
2081   SDValue Src = Op.getOperand(0);
2082 
2083   // result = trunc(src)
2084   // if (src > 0.0 && src != result)
2085   //   result += 1.0
2086 
2087   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2088 
2089   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2090   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2091 
2092   EVT SetCCVT =
2093       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2094 
2095   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2096   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2097   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2098 
2099   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2100   // TODO: Should this propagate fast-math-flags?
2101   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2102 }
2103 
2104 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2105                                   SelectionDAG &DAG) {
2106   const unsigned FractBits = 52;
2107   const unsigned ExpBits = 11;
2108 
2109   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2110                                 Hi,
2111                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2112                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2113   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2114                             DAG.getConstant(1023, SL, MVT::i32));
2115 
2116   return Exp;
2117 }
2118 
2119 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2120   SDLoc SL(Op);
2121   SDValue Src = Op.getOperand(0);
2122 
2123   assert(Op.getValueType() == MVT::f64);
2124 
2125   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2126   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2127 
2128   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2129 
2130   // Extract the upper half, since this is where we will find the sign and
2131   // exponent.
2132   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2133 
2134   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2135 
2136   const unsigned FractBits = 52;
2137 
2138   // Extract the sign bit.
2139   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2140   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2141 
2142   // Extend back to 64-bits.
2143   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2144   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2145 
2146   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2147   const SDValue FractMask
2148     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2149 
2150   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2151   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2152   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2153 
2154   EVT SetCCVT =
2155       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2156 
2157   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2158 
2159   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2160   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2161 
2162   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2163   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2164 
2165   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2166 }
2167 
2168 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2169   SDLoc SL(Op);
2170   SDValue Src = Op.getOperand(0);
2171 
2172   assert(Op.getValueType() == MVT::f64);
2173 
2174   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2175   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2176   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2177 
2178   // TODO: Should this propagate fast-math-flags?
2179 
2180   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2181   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2182 
2183   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2184 
2185   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2186   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2187 
2188   EVT SetCCVT =
2189       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2190   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2191 
2192   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2193 }
2194 
2195 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2196   // FNEARBYINT and FRINT are the same, except in their handling of FP
2197   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2198   // rint, so just treat them as equivalent.
2199   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2200 }
2201 
2202 // XXX - May require not supporting f32 denormals?
2203 
2204 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2205 // compare and vselect end up producing worse code than scalarizing the whole
2206 // operation.
2207 SDValue AMDGPUTargetLowering::LowerFROUND_LegalFTRUNC(SDValue Op,
2208                                                       SelectionDAG &DAG) const {
2209   SDLoc SL(Op);
2210   SDValue X = Op.getOperand(0);
2211   EVT VT = Op.getValueType();
2212 
2213   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2214 
2215   // TODO: Should this propagate fast-math-flags?
2216 
2217   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2218 
2219   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2220 
2221   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2222   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2223   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2224 
2225   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2226 
2227   EVT SetCCVT =
2228       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2229 
2230   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2231 
2232   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2233 
2234   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2235 }
2236 
2237 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
2238   SDLoc SL(Op);
2239   SDValue X = Op.getOperand(0);
2240 
2241   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
2242 
2243   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2244   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2245   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
2246   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
2247   EVT SetCCVT =
2248       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2249 
2250   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
2251 
2252   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
2253 
2254   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2255 
2256   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
2257                                        MVT::i64);
2258 
2259   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
2260   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
2261                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
2262                                           MVT::i64),
2263                           Exp);
2264 
2265   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
2266   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
2267                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
2268                               ISD::SETNE);
2269 
2270   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
2271                              D, DAG.getConstant(0, SL, MVT::i64));
2272   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
2273 
2274   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
2275   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
2276 
2277   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2278   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2279   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
2280 
2281   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
2282                             ExpEqNegOne,
2283                             DAG.getConstantFP(1.0, SL, MVT::f64),
2284                             DAG.getConstantFP(0.0, SL, MVT::f64));
2285 
2286   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
2287 
2288   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
2289   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
2290 
2291   return K;
2292 }
2293 
2294 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2295   EVT VT = Op.getValueType();
2296 
2297   if (isOperationLegal(ISD::FTRUNC, VT))
2298     return LowerFROUND_LegalFTRUNC(Op, DAG);
2299 
2300   if (VT == MVT::f64)
2301     return LowerFROUND64(Op, DAG);
2302 
2303   llvm_unreachable("unhandled type");
2304 }
2305 
2306 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2307   SDLoc SL(Op);
2308   SDValue Src = Op.getOperand(0);
2309 
2310   // result = trunc(src);
2311   // if (src < 0.0 && src != result)
2312   //   result += -1.0.
2313 
2314   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2315 
2316   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2317   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2318 
2319   EVT SetCCVT =
2320       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2321 
2322   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2323   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2324   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2325 
2326   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2327   // TODO: Should this propagate fast-math-flags?
2328   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2329 }
2330 
2331 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2332                                         double Log2BaseInverted) const {
2333   EVT VT = Op.getValueType();
2334 
2335   SDLoc SL(Op);
2336   SDValue Operand = Op.getOperand(0);
2337   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2338   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2339 
2340   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2341 }
2342 
2343 // exp2(M_LOG2E_F * f);
2344 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2345   EVT VT = Op.getValueType();
2346   SDLoc SL(Op);
2347   SDValue Src = Op.getOperand(0);
2348 
2349   const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
2350   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2351   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2352 }
2353 
2354 static bool isCtlzOpc(unsigned Opc) {
2355   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2356 }
2357 
2358 static bool isCttzOpc(unsigned Opc) {
2359   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2360 }
2361 
2362 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2363   SDLoc SL(Op);
2364   SDValue Src = Op.getOperand(0);
2365   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2366                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2367 
2368   unsigned ISDOpc, NewOpc;
2369   if (isCtlzOpc(Op.getOpcode())) {
2370     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2371     NewOpc = AMDGPUISD::FFBH_U32;
2372   } else if (isCttzOpc(Op.getOpcode())) {
2373     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2374     NewOpc = AMDGPUISD::FFBL_B32;
2375   } else
2376     llvm_unreachable("Unexpected OPCode!!!");
2377 
2378 
2379   if (ZeroUndef && Src.getValueType() == MVT::i32)
2380     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2381 
2382   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2383 
2384   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2385   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2386 
2387   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2388   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2389 
2390   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2391                                    *DAG.getContext(), MVT::i32);
2392 
2393   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2394   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2395 
2396   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2397   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2398 
2399   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2400   SDValue Add, NewOpr;
2401   if (isCtlzOpc(Op.getOpcode())) {
2402     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2403     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2404     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2405   } else {
2406     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2407     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2408     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2409   }
2410 
2411   if (!ZeroUndef) {
2412     // Test if the full 64-bit input is zero.
2413 
2414     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2415     // which we probably don't want.
2416     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2417     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2418     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2419 
2420     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2421     // with the same cycles, otherwise it is slower.
2422     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2423     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2424 
2425     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2426 
2427     // The instruction returns -1 for 0 input, but the defined intrinsic
2428     // behavior is to return the number of bits.
2429     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2430                          SrcIsZero, Bits32, NewOpr);
2431   }
2432 
2433   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2434 }
2435 
2436 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2437                                                bool Signed) const {
2438   // Unsigned
2439   // cul2f(ulong u)
2440   //{
2441   //  uint lz = clz(u);
2442   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2443   //  u = (u << lz) & 0x7fffffffffffffffUL;
2444   //  ulong t = u & 0xffffffffffUL;
2445   //  uint v = (e << 23) | (uint)(u >> 40);
2446   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2447   //  return as_float(v + r);
2448   //}
2449   // Signed
2450   // cl2f(long l)
2451   //{
2452   //  long s = l >> 63;
2453   //  float r = cul2f((l + s) ^ s);
2454   //  return s ? -r : r;
2455   //}
2456 
2457   SDLoc SL(Op);
2458   SDValue Src = Op.getOperand(0);
2459   SDValue L = Src;
2460 
2461   SDValue S;
2462   if (Signed) {
2463     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2464     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2465 
2466     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2467     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2468   }
2469 
2470   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2471                                    *DAG.getContext(), MVT::f32);
2472 
2473 
2474   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2475   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2476   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2477   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2478 
2479   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2480   SDValue E = DAG.getSelect(SL, MVT::i32,
2481     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2482     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2483     ZeroI32);
2484 
2485   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2486     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2487     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2488 
2489   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2490                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2491 
2492   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2493                              U, DAG.getConstant(40, SL, MVT::i64));
2494 
2495   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2496     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2497     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2498 
2499   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2500   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2501   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2502 
2503   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2504 
2505   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2506 
2507   SDValue R = DAG.getSelect(SL, MVT::i32,
2508     RCmp,
2509     One,
2510     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2511   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2512   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2513 
2514   if (!Signed)
2515     return R;
2516 
2517   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2518   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2519 }
2520 
2521 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2522                                                bool Signed) const {
2523   SDLoc SL(Op);
2524   SDValue Src = Op.getOperand(0);
2525 
2526   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2527 
2528   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2529                            DAG.getConstant(0, SL, MVT::i32));
2530   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2531                            DAG.getConstant(1, SL, MVT::i32));
2532 
2533   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2534                               SL, MVT::f64, Hi);
2535 
2536   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2537 
2538   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2539                               DAG.getConstant(32, SL, MVT::i32));
2540   // TODO: Should this propagate fast-math-flags?
2541   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2542 }
2543 
2544 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2545                                                SelectionDAG &DAG) const {
2546   // TODO: Factor out code common with LowerSINT_TO_FP.
2547   EVT DestVT = Op.getValueType();
2548   SDValue Src = Op.getOperand(0);
2549   EVT SrcVT = Src.getValueType();
2550 
2551   if (SrcVT == MVT::i16) {
2552     if (DestVT == MVT::f16)
2553       return Op;
2554     SDLoc DL(Op);
2555 
2556     // Promote src to i32
2557     SDValue Ext = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Src);
2558     return DAG.getNode(ISD::UINT_TO_FP, DL, DestVT, Ext);
2559   }
2560 
2561   assert(SrcVT == MVT::i64 && "operation should be legal");
2562 
2563   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2564     SDLoc DL(Op);
2565 
2566     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2567     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2568     SDValue FPRound =
2569         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2570 
2571     return FPRound;
2572   }
2573 
2574   if (DestVT == MVT::f32)
2575     return LowerINT_TO_FP32(Op, DAG, false);
2576 
2577   assert(DestVT == MVT::f64);
2578   return LowerINT_TO_FP64(Op, DAG, false);
2579 }
2580 
2581 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2582                                               SelectionDAG &DAG) const {
2583   EVT DestVT = Op.getValueType();
2584 
2585   SDValue Src = Op.getOperand(0);
2586   EVT SrcVT = Src.getValueType();
2587 
2588   if (SrcVT == MVT::i16) {
2589     if (DestVT == MVT::f16)
2590       return Op;
2591 
2592     SDLoc DL(Op);
2593     // Promote src to i32
2594     SDValue Ext = DAG.getNode(ISD::SIGN_EXTEND, DL, MVT::i32, Src);
2595     return DAG.getNode(ISD::SINT_TO_FP, DL, DestVT, Ext);
2596   }
2597 
2598   assert(SrcVT == MVT::i64 && "operation should be legal");
2599 
2600   // TODO: Factor out code common with LowerUINT_TO_FP.
2601 
2602   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2603     SDLoc DL(Op);
2604     SDValue Src = Op.getOperand(0);
2605 
2606     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2607     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2608     SDValue FPRound =
2609         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2610 
2611     return FPRound;
2612   }
2613 
2614   if (DestVT == MVT::f32)
2615     return LowerINT_TO_FP32(Op, DAG, true);
2616 
2617   assert(DestVT == MVT::f64);
2618   return LowerINT_TO_FP64(Op, DAG, true);
2619 }
2620 
2621 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2622                                                bool Signed) const {
2623   SDLoc SL(Op);
2624 
2625   SDValue Src = Op.getOperand(0);
2626 
2627   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2628 
2629   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2630                                  MVT::f64);
2631   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2632                                  MVT::f64);
2633   // TODO: Should this propagate fast-math-flags?
2634   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2635 
2636   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2637 
2638 
2639   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2640 
2641   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2642                            MVT::i32, FloorMul);
2643   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2644 
2645   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2646 
2647   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2648 }
2649 
2650 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2651   SDLoc DL(Op);
2652   SDValue N0 = Op.getOperand(0);
2653 
2654   // Convert to target node to get known bits
2655   if (N0.getValueType() == MVT::f32)
2656     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2657 
2658   if (getTargetMachine().Options.UnsafeFPMath) {
2659     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2660     return SDValue();
2661   }
2662 
2663   assert(N0.getSimpleValueType() == MVT::f64);
2664 
2665   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2666   const unsigned ExpMask = 0x7ff;
2667   const unsigned ExpBiasf64 = 1023;
2668   const unsigned ExpBiasf16 = 15;
2669   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2670   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2671   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2672   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2673                            DAG.getConstant(32, DL, MVT::i64));
2674   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2675   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2676   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2677                           DAG.getConstant(20, DL, MVT::i64));
2678   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2679                   DAG.getConstant(ExpMask, DL, MVT::i32));
2680   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2681   // add the f16 bias (15) to get the biased exponent for the f16 format.
2682   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2683                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2684 
2685   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2686                           DAG.getConstant(8, DL, MVT::i32));
2687   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2688                   DAG.getConstant(0xffe, DL, MVT::i32));
2689 
2690   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2691                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2692   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2693 
2694   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2695   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2696 
2697   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2698   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2699       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2700                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2701 
2702   // N = M | (E << 12);
2703   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2704       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2705                   DAG.getConstant(12, DL, MVT::i32)));
2706 
2707   // B = clamp(1-E, 0, 13);
2708   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2709                                   One, E);
2710   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2711   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2712                   DAG.getConstant(13, DL, MVT::i32));
2713 
2714   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2715                                    DAG.getConstant(0x1000, DL, MVT::i32));
2716 
2717   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2718   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2719   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2720   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2721 
2722   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2723   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2724                               DAG.getConstant(0x7, DL, MVT::i32));
2725   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2726                   DAG.getConstant(2, DL, MVT::i32));
2727   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2728                                One, Zero, ISD::SETEQ);
2729   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2730                                One, Zero, ISD::SETGT);
2731   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2732   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2733 
2734   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2735                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2736   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2737                       I, V, ISD::SETEQ);
2738 
2739   // Extract the sign bit.
2740   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2741                             DAG.getConstant(16, DL, MVT::i32));
2742   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2743                      DAG.getConstant(0x8000, DL, MVT::i32));
2744 
2745   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2746   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2747 }
2748 
2749 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2750                                               SelectionDAG &DAG) const {
2751   SDValue Src = Op.getOperand(0);
2752 
2753   // TODO: Factor out code common with LowerFP_TO_UINT.
2754 
2755   EVT SrcVT = Src.getValueType();
2756   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2757     SDLoc DL(Op);
2758 
2759     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2760     SDValue FpToInt32 =
2761         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2762 
2763     return FpToInt32;
2764   }
2765 
2766   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2767     return LowerFP64_TO_INT(Op, DAG, true);
2768 
2769   return SDValue();
2770 }
2771 
2772 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2773                                               SelectionDAG &DAG) const {
2774   SDValue Src = Op.getOperand(0);
2775 
2776   // TODO: Factor out code common with LowerFP_TO_SINT.
2777 
2778   EVT SrcVT = Src.getValueType();
2779   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2780     SDLoc DL(Op);
2781 
2782     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2783     SDValue FpToInt32 =
2784         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2785 
2786     return FpToInt32;
2787   }
2788 
2789   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2790     return LowerFP64_TO_INT(Op, DAG, false);
2791 
2792   return SDValue();
2793 }
2794 
2795 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2796                                                      SelectionDAG &DAG) const {
2797   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2798   MVT VT = Op.getSimpleValueType();
2799   MVT ScalarVT = VT.getScalarType();
2800 
2801   assert(VT.isVector());
2802 
2803   SDValue Src = Op.getOperand(0);
2804   SDLoc DL(Op);
2805 
2806   // TODO: Don't scalarize on Evergreen?
2807   unsigned NElts = VT.getVectorNumElements();
2808   SmallVector<SDValue, 8> Args;
2809   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2810 
2811   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2812   for (unsigned I = 0; I < NElts; ++I)
2813     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2814 
2815   return DAG.getBuildVector(VT, DL, Args);
2816 }
2817 
2818 //===----------------------------------------------------------------------===//
2819 // Custom DAG optimizations
2820 //===----------------------------------------------------------------------===//
2821 
2822 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2823   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2824 }
2825 
2826 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2827   EVT VT = Op.getValueType();
2828   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2829                                      // as unsigned 24-bit values.
2830     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2831 }
2832 
2833 static SDValue simplifyI24(SDNode *Node24,
2834                            TargetLowering::DAGCombinerInfo &DCI) {
2835   SelectionDAG &DAG = DCI.DAG;
2836   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2837   bool IsIntrin = Node24->getOpcode() == ISD::INTRINSIC_WO_CHAIN;
2838 
2839   SDValue LHS = IsIntrin ? Node24->getOperand(1) : Node24->getOperand(0);
2840   SDValue RHS = IsIntrin ? Node24->getOperand(2) : Node24->getOperand(1);
2841   unsigned NewOpcode = Node24->getOpcode();
2842   if (IsIntrin) {
2843     unsigned IID = cast<ConstantSDNode>(Node24->getOperand(0))->getZExtValue();
2844     NewOpcode = IID == Intrinsic::amdgcn_mul_i24 ?
2845       AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
2846   }
2847 
2848   APInt Demanded = APInt::getLowBitsSet(LHS.getValueSizeInBits(), 24);
2849 
2850   // First try to simplify using SimplifyMultipleUseDemandedBits which allows
2851   // the operands to have other uses, but will only perform simplifications that
2852   // involve bypassing some nodes for this user.
2853   SDValue DemandedLHS = TLI.SimplifyMultipleUseDemandedBits(LHS, Demanded, DAG);
2854   SDValue DemandedRHS = TLI.SimplifyMultipleUseDemandedBits(RHS, Demanded, DAG);
2855   if (DemandedLHS || DemandedRHS)
2856     return DAG.getNode(NewOpcode, SDLoc(Node24), Node24->getVTList(),
2857                        DemandedLHS ? DemandedLHS : LHS,
2858                        DemandedRHS ? DemandedRHS : RHS);
2859 
2860   // Now try SimplifyDemandedBits which can simplify the nodes used by our
2861   // operands if this node is the only user.
2862   if (TLI.SimplifyDemandedBits(LHS, Demanded, DCI))
2863     return SDValue(Node24, 0);
2864   if (TLI.SimplifyDemandedBits(RHS, Demanded, DCI))
2865     return SDValue(Node24, 0);
2866 
2867   return SDValue();
2868 }
2869 
2870 template <typename IntTy>
2871 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2872                                uint32_t Width, const SDLoc &DL) {
2873   if (Width + Offset < 32) {
2874     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2875     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2876     return DAG.getConstant(Result, DL, MVT::i32);
2877   }
2878 
2879   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2880 }
2881 
2882 static bool hasVolatileUser(SDNode *Val) {
2883   for (SDNode *U : Val->uses()) {
2884     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2885       if (M->isVolatile())
2886         return true;
2887     }
2888   }
2889 
2890   return false;
2891 }
2892 
2893 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2894   // i32 vectors are the canonical memory type.
2895   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2896     return false;
2897 
2898   if (!VT.isByteSized())
2899     return false;
2900 
2901   unsigned Size = VT.getStoreSize();
2902 
2903   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2904     return false;
2905 
2906   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2907     return false;
2908 
2909   return true;
2910 }
2911 
2912 // Replace load of an illegal type with a store of a bitcast to a friendlier
2913 // type.
2914 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2915                                                  DAGCombinerInfo &DCI) const {
2916   if (!DCI.isBeforeLegalize())
2917     return SDValue();
2918 
2919   LoadSDNode *LN = cast<LoadSDNode>(N);
2920   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2921     return SDValue();
2922 
2923   SDLoc SL(N);
2924   SelectionDAG &DAG = DCI.DAG;
2925   EVT VT = LN->getMemoryVT();
2926 
2927   unsigned Size = VT.getStoreSize();
2928   unsigned Align = LN->getAlignment();
2929   if (Align < Size && isTypeLegal(VT)) {
2930     bool IsFast;
2931     unsigned AS = LN->getAddressSpace();
2932 
2933     // Expand unaligned loads earlier than legalization. Due to visitation order
2934     // problems during legalization, the emitted instructions to pack and unpack
2935     // the bytes again are not eliminated in the case of an unaligned copy.
2936     if (!allowsMisalignedMemoryAccesses(
2937             VT, AS, Align, LN->getMemOperand()->getFlags(), &IsFast)) {
2938       SDValue Ops[2];
2939 
2940       if (VT.isVector())
2941         std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(LN, DAG);
2942       else
2943         std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2944 
2945       return DAG.getMergeValues(Ops, SDLoc(N));
2946     }
2947 
2948     if (!IsFast)
2949       return SDValue();
2950   }
2951 
2952   if (!shouldCombineMemoryType(VT))
2953     return SDValue();
2954 
2955   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2956 
2957   SDValue NewLoad
2958     = DAG.getLoad(NewVT, SL, LN->getChain(),
2959                   LN->getBasePtr(), LN->getMemOperand());
2960 
2961   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2962   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2963   return SDValue(N, 0);
2964 }
2965 
2966 // Replace store of an illegal type with a store of a bitcast to a friendlier
2967 // type.
2968 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2969                                                   DAGCombinerInfo &DCI) const {
2970   if (!DCI.isBeforeLegalize())
2971     return SDValue();
2972 
2973   StoreSDNode *SN = cast<StoreSDNode>(N);
2974   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2975     return SDValue();
2976 
2977   EVT VT = SN->getMemoryVT();
2978   unsigned Size = VT.getStoreSize();
2979 
2980   SDLoc SL(N);
2981   SelectionDAG &DAG = DCI.DAG;
2982   unsigned Align = SN->getAlignment();
2983   if (Align < Size && isTypeLegal(VT)) {
2984     bool IsFast;
2985     unsigned AS = SN->getAddressSpace();
2986 
2987     // Expand unaligned stores earlier than legalization. Due to visitation
2988     // order problems during legalization, the emitted instructions to pack and
2989     // unpack the bytes again are not eliminated in the case of an unaligned
2990     // copy.
2991     if (!allowsMisalignedMemoryAccesses(
2992             VT, AS, Align, SN->getMemOperand()->getFlags(), &IsFast)) {
2993       if (VT.isVector())
2994         return scalarizeVectorStore(SN, DAG);
2995 
2996       return expandUnalignedStore(SN, DAG);
2997     }
2998 
2999     if (!IsFast)
3000       return SDValue();
3001   }
3002 
3003   if (!shouldCombineMemoryType(VT))
3004     return SDValue();
3005 
3006   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
3007   SDValue Val = SN->getValue();
3008 
3009   //DCI.AddToWorklist(Val.getNode());
3010 
3011   bool OtherUses = !Val.hasOneUse();
3012   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
3013   if (OtherUses) {
3014     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
3015     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
3016   }
3017 
3018   return DAG.getStore(SN->getChain(), SL, CastVal,
3019                       SN->getBasePtr(), SN->getMemOperand());
3020 }
3021 
3022 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
3023 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
3024 // issues.
3025 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
3026                                                         DAGCombinerInfo &DCI) const {
3027   SelectionDAG &DAG = DCI.DAG;
3028   SDValue N0 = N->getOperand(0);
3029 
3030   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
3031   //     (vt2 (truncate (assertzext vt0:x, vt1)))
3032   if (N0.getOpcode() == ISD::TRUNCATE) {
3033     SDValue N1 = N->getOperand(1);
3034     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
3035     SDLoc SL(N);
3036 
3037     SDValue Src = N0.getOperand(0);
3038     EVT SrcVT = Src.getValueType();
3039     if (SrcVT.bitsGE(ExtVT)) {
3040       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
3041       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
3042     }
3043   }
3044 
3045   return SDValue();
3046 }
3047 
3048 SDValue AMDGPUTargetLowering::performIntrinsicWOChainCombine(
3049   SDNode *N, DAGCombinerInfo &DCI) const {
3050   unsigned IID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
3051   switch (IID) {
3052   case Intrinsic::amdgcn_mul_i24:
3053   case Intrinsic::amdgcn_mul_u24:
3054     return simplifyI24(N, DCI);
3055   default:
3056     return SDValue();
3057   }
3058 }
3059 
3060 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
3061 /// binary operation \p Opc to it with the corresponding constant operands.
3062 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
3063   DAGCombinerInfo &DCI, const SDLoc &SL,
3064   unsigned Opc, SDValue LHS,
3065   uint32_t ValLo, uint32_t ValHi) const {
3066   SelectionDAG &DAG = DCI.DAG;
3067   SDValue Lo, Hi;
3068   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
3069 
3070   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
3071   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
3072 
3073   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
3074   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
3075 
3076   // Re-visit the ands. It's possible we eliminated one of them and it could
3077   // simplify the vector.
3078   DCI.AddToWorklist(Lo.getNode());
3079   DCI.AddToWorklist(Hi.getNode());
3080 
3081   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
3082   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3083 }
3084 
3085 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
3086                                                 DAGCombinerInfo &DCI) const {
3087   EVT VT = N->getValueType(0);
3088 
3089   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3090   if (!RHS)
3091     return SDValue();
3092 
3093   SDValue LHS = N->getOperand(0);
3094   unsigned RHSVal = RHS->getZExtValue();
3095   if (!RHSVal)
3096     return LHS;
3097 
3098   SDLoc SL(N);
3099   SelectionDAG &DAG = DCI.DAG;
3100 
3101   switch (LHS->getOpcode()) {
3102   default:
3103     break;
3104   case ISD::ZERO_EXTEND:
3105   case ISD::SIGN_EXTEND:
3106   case ISD::ANY_EXTEND: {
3107     SDValue X = LHS->getOperand(0);
3108 
3109     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
3110         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
3111       // Prefer build_vector as the canonical form if packed types are legal.
3112       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
3113       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
3114        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
3115       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
3116     }
3117 
3118     // shl (ext x) => zext (shl x), if shift does not overflow int
3119     if (VT != MVT::i64)
3120       break;
3121     KnownBits Known = DAG.computeKnownBits(X);
3122     unsigned LZ = Known.countMinLeadingZeros();
3123     if (LZ < RHSVal)
3124       break;
3125     EVT XVT = X.getValueType();
3126     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
3127     return DAG.getZExtOrTrunc(Shl, SL, VT);
3128   }
3129   }
3130 
3131   if (VT != MVT::i64)
3132     return SDValue();
3133 
3134   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3135 
3136   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3137   // common case, splitting this into a move and a 32-bit shift is faster and
3138   // the same code size.
3139   if (RHSVal < 32)
3140     return SDValue();
3141 
3142   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3143 
3144   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3145   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3146 
3147   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3148 
3149   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3150   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3151 }
3152 
3153 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3154                                                 DAGCombinerInfo &DCI) const {
3155   if (N->getValueType(0) != MVT::i64)
3156     return SDValue();
3157 
3158   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3159   if (!RHS)
3160     return SDValue();
3161 
3162   SelectionDAG &DAG = DCI.DAG;
3163   SDLoc SL(N);
3164   unsigned RHSVal = RHS->getZExtValue();
3165 
3166   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3167   if (RHSVal == 32) {
3168     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3169     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3170                                    DAG.getConstant(31, SL, MVT::i32));
3171 
3172     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3173     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3174   }
3175 
3176   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3177   if (RHSVal == 63) {
3178     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3179     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3180                                    DAG.getConstant(31, SL, MVT::i32));
3181     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3182     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3183   }
3184 
3185   return SDValue();
3186 }
3187 
3188 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3189                                                 DAGCombinerInfo &DCI) const {
3190   auto *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3191   if (!RHS)
3192     return SDValue();
3193 
3194   EVT VT = N->getValueType(0);
3195   SDValue LHS = N->getOperand(0);
3196   unsigned ShiftAmt = RHS->getZExtValue();
3197   SelectionDAG &DAG = DCI.DAG;
3198   SDLoc SL(N);
3199 
3200   // fold (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1)
3201   // this improves the ability to match BFE patterns in isel.
3202   if (LHS.getOpcode() == ISD::AND) {
3203     if (auto *Mask = dyn_cast<ConstantSDNode>(LHS.getOperand(1))) {
3204       if (Mask->getAPIntValue().isShiftedMask() &&
3205           Mask->getAPIntValue().countTrailingZeros() == ShiftAmt) {
3206         return DAG.getNode(
3207             ISD::AND, SL, VT,
3208             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(0), N->getOperand(1)),
3209             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(1), N->getOperand(1)));
3210       }
3211     }
3212   }
3213 
3214   if (VT != MVT::i64)
3215     return SDValue();
3216 
3217   if (ShiftAmt < 32)
3218     return SDValue();
3219 
3220   // srl i64:x, C for C >= 32
3221   // =>
3222   //   build_pair (srl hi_32(x), C - 32), 0
3223   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3224   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3225 
3226   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, LHS);
3227   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecOp, One);
3228 
3229   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3230   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3231 
3232   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3233 
3234   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3235 }
3236 
3237 SDValue AMDGPUTargetLowering::performTruncateCombine(
3238   SDNode *N, DAGCombinerInfo &DCI) const {
3239   SDLoc SL(N);
3240   SelectionDAG &DAG = DCI.DAG;
3241   EVT VT = N->getValueType(0);
3242   SDValue Src = N->getOperand(0);
3243 
3244   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3245   if (Src.getOpcode() == ISD::BITCAST && !VT.isVector()) {
3246     SDValue Vec = Src.getOperand(0);
3247     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3248       SDValue Elt0 = Vec.getOperand(0);
3249       EVT EltVT = Elt0.getValueType();
3250       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3251         if (EltVT.isFloatingPoint()) {
3252           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3253                              EltVT.changeTypeToInteger(), Elt0);
3254         }
3255 
3256         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3257       }
3258     }
3259   }
3260 
3261   // Equivalent of above for accessing the high element of a vector as an
3262   // integer operation.
3263   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3264   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3265     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3266       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3267         SDValue BV = stripBitcast(Src.getOperand(0));
3268         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3269             BV.getValueType().getVectorNumElements() == 2) {
3270           SDValue SrcElt = BV.getOperand(1);
3271           EVT SrcEltVT = SrcElt.getValueType();
3272           if (SrcEltVT.isFloatingPoint()) {
3273             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3274                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3275           }
3276 
3277           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3278         }
3279       }
3280     }
3281   }
3282 
3283   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3284   //
3285   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3286   //     i16 (trunc (srl (i32 (trunc x), K)))
3287   if (VT.getScalarSizeInBits() < 32) {
3288     EVT SrcVT = Src.getValueType();
3289     if (SrcVT.getScalarSizeInBits() > 32 &&
3290         (Src.getOpcode() == ISD::SRL ||
3291          Src.getOpcode() == ISD::SRA ||
3292          Src.getOpcode() == ISD::SHL)) {
3293       SDValue Amt = Src.getOperand(1);
3294       KnownBits Known = DAG.computeKnownBits(Amt);
3295       unsigned Size = VT.getScalarSizeInBits();
3296       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3297           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3298         EVT MidVT = VT.isVector() ?
3299           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3300                            VT.getVectorNumElements()) : MVT::i32;
3301 
3302         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3303         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3304                                     Src.getOperand(0));
3305         DCI.AddToWorklist(Trunc.getNode());
3306 
3307         if (Amt.getValueType() != NewShiftVT) {
3308           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3309           DCI.AddToWorklist(Amt.getNode());
3310         }
3311 
3312         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3313                                           Trunc, Amt);
3314         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3315       }
3316     }
3317   }
3318 
3319   return SDValue();
3320 }
3321 
3322 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3323 // instructions. If we only match on the legalized i64 mul expansion,
3324 // SimplifyDemandedBits will be unable to remove them because there will be
3325 // multiple uses due to the separate mul + mulh[su].
3326 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3327                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3328   if (Size <= 32) {
3329     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3330     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3331   }
3332 
3333   // Because we want to eliminate extension instructions before the
3334   // operation, we need to create a single user here (i.e. not the separate
3335   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3336 
3337   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3338 
3339   SDValue Mul = DAG.getNode(MulOpc, SL,
3340                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3341 
3342   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3343                      Mul.getValue(0), Mul.getValue(1));
3344 }
3345 
3346 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3347                                                 DAGCombinerInfo &DCI) const {
3348   EVT VT = N->getValueType(0);
3349 
3350   unsigned Size = VT.getSizeInBits();
3351   if (VT.isVector() || Size > 64)
3352     return SDValue();
3353 
3354   // There are i16 integer mul/mad.
3355   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3356     return SDValue();
3357 
3358   SelectionDAG &DAG = DCI.DAG;
3359   SDLoc DL(N);
3360 
3361   SDValue N0 = N->getOperand(0);
3362   SDValue N1 = N->getOperand(1);
3363 
3364   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3365   // in the source into any_extends if the result of the mul is truncated. Since
3366   // we can assume the high bits are whatever we want, use the underlying value
3367   // to avoid the unknown high bits from interfering.
3368   if (N0.getOpcode() == ISD::ANY_EXTEND)
3369     N0 = N0.getOperand(0);
3370 
3371   if (N1.getOpcode() == ISD::ANY_EXTEND)
3372     N1 = N1.getOperand(0);
3373 
3374   SDValue Mul;
3375 
3376   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3377     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3378     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3379     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3380   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3381     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3382     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3383     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3384   } else {
3385     return SDValue();
3386   }
3387 
3388   // We need to use sext even for MUL_U24, because MUL_U24 is used
3389   // for signed multiply of 8 and 16-bit types.
3390   return DAG.getSExtOrTrunc(Mul, DL, VT);
3391 }
3392 
3393 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3394                                                   DAGCombinerInfo &DCI) const {
3395   EVT VT = N->getValueType(0);
3396 
3397   if (!Subtarget->hasMulI24() || VT.isVector())
3398     return SDValue();
3399 
3400   SelectionDAG &DAG = DCI.DAG;
3401   SDLoc DL(N);
3402 
3403   SDValue N0 = N->getOperand(0);
3404   SDValue N1 = N->getOperand(1);
3405 
3406   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3407     return SDValue();
3408 
3409   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3410   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3411 
3412   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3413   DCI.AddToWorklist(Mulhi.getNode());
3414   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3415 }
3416 
3417 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3418                                                   DAGCombinerInfo &DCI) const {
3419   EVT VT = N->getValueType(0);
3420 
3421   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3422     return SDValue();
3423 
3424   SelectionDAG &DAG = DCI.DAG;
3425   SDLoc DL(N);
3426 
3427   SDValue N0 = N->getOperand(0);
3428   SDValue N1 = N->getOperand(1);
3429 
3430   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3431     return SDValue();
3432 
3433   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3434   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3435 
3436   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3437   DCI.AddToWorklist(Mulhi.getNode());
3438   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3439 }
3440 
3441 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3442   SDNode *N, DAGCombinerInfo &DCI) const {
3443   SelectionDAG &DAG = DCI.DAG;
3444 
3445   // Simplify demanded bits before splitting into multiple users.
3446   if (SDValue V = simplifyI24(N, DCI))
3447     return V;
3448 
3449   SDValue N0 = N->getOperand(0);
3450   SDValue N1 = N->getOperand(1);
3451 
3452   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3453 
3454   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3455   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3456 
3457   SDLoc SL(N);
3458 
3459   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3460   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3461   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3462 }
3463 
3464 static bool isNegativeOne(SDValue Val) {
3465   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3466     return C->isAllOnesValue();
3467   return false;
3468 }
3469 
3470 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3471                                           SDValue Op,
3472                                           const SDLoc &DL,
3473                                           unsigned Opc) const {
3474   EVT VT = Op.getValueType();
3475   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3476   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3477                               LegalVT != MVT::i16))
3478     return SDValue();
3479 
3480   if (VT != MVT::i32)
3481     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3482 
3483   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3484   if (VT != MVT::i32)
3485     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3486 
3487   return FFBX;
3488 }
3489 
3490 // The native instructions return -1 on 0 input. Optimize out a select that
3491 // produces -1 on 0.
3492 //
3493 // TODO: If zero is not undef, we could also do this if the output is compared
3494 // against the bitwidth.
3495 //
3496 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3497 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3498                                                  SDValue LHS, SDValue RHS,
3499                                                  DAGCombinerInfo &DCI) const {
3500   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3501   if (!CmpRhs || !CmpRhs->isNullValue())
3502     return SDValue();
3503 
3504   SelectionDAG &DAG = DCI.DAG;
3505   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3506   SDValue CmpLHS = Cond.getOperand(0);
3507 
3508   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3509                                            AMDGPUISD::FFBH_U32;
3510 
3511   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3512   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3513   if (CCOpcode == ISD::SETEQ &&
3514       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3515       RHS.getOperand(0) == CmpLHS &&
3516       isNegativeOne(LHS)) {
3517     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3518   }
3519 
3520   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3521   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3522   if (CCOpcode == ISD::SETNE &&
3523       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3524       LHS.getOperand(0) == CmpLHS &&
3525       isNegativeOne(RHS)) {
3526     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3527   }
3528 
3529   return SDValue();
3530 }
3531 
3532 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3533                                          unsigned Op,
3534                                          const SDLoc &SL,
3535                                          SDValue Cond,
3536                                          SDValue N1,
3537                                          SDValue N2) {
3538   SelectionDAG &DAG = DCI.DAG;
3539   EVT VT = N1.getValueType();
3540 
3541   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3542                                   N1.getOperand(0), N2.getOperand(0));
3543   DCI.AddToWorklist(NewSelect.getNode());
3544   return DAG.getNode(Op, SL, VT, NewSelect);
3545 }
3546 
3547 // Pull a free FP operation out of a select so it may fold into uses.
3548 //
3549 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3550 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3551 //
3552 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3553 // select c, (fabs x), +k -> fabs (select c, x, k)
3554 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3555                                     SDValue N) {
3556   SelectionDAG &DAG = DCI.DAG;
3557   SDValue Cond = N.getOperand(0);
3558   SDValue LHS = N.getOperand(1);
3559   SDValue RHS = N.getOperand(2);
3560 
3561   EVT VT = N.getValueType();
3562   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3563       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3564     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3565                                      SDLoc(N), Cond, LHS, RHS);
3566   }
3567 
3568   bool Inv = false;
3569   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3570     std::swap(LHS, RHS);
3571     Inv = true;
3572   }
3573 
3574   // TODO: Support vector constants.
3575   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3576   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3577     SDLoc SL(N);
3578     // If one side is an fneg/fabs and the other is a constant, we can push the
3579     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3580     SDValue NewLHS = LHS.getOperand(0);
3581     SDValue NewRHS = RHS;
3582 
3583     // Careful: if the neg can be folded up, don't try to pull it back down.
3584     bool ShouldFoldNeg = true;
3585 
3586     if (NewLHS.hasOneUse()) {
3587       unsigned Opc = NewLHS.getOpcode();
3588       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3589         ShouldFoldNeg = false;
3590       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3591         ShouldFoldNeg = false;
3592     }
3593 
3594     if (ShouldFoldNeg) {
3595       if (LHS.getOpcode() == ISD::FNEG)
3596         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3597       else if (CRHS->isNegative())
3598         return SDValue();
3599 
3600       if (Inv)
3601         std::swap(NewLHS, NewRHS);
3602 
3603       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3604                                       Cond, NewLHS, NewRHS);
3605       DCI.AddToWorklist(NewSelect.getNode());
3606       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3607     }
3608   }
3609 
3610   return SDValue();
3611 }
3612 
3613 
3614 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3615                                                    DAGCombinerInfo &DCI) const {
3616   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3617     return Folded;
3618 
3619   SDValue Cond = N->getOperand(0);
3620   if (Cond.getOpcode() != ISD::SETCC)
3621     return SDValue();
3622 
3623   EVT VT = N->getValueType(0);
3624   SDValue LHS = Cond.getOperand(0);
3625   SDValue RHS = Cond.getOperand(1);
3626   SDValue CC = Cond.getOperand(2);
3627 
3628   SDValue True = N->getOperand(1);
3629   SDValue False = N->getOperand(2);
3630 
3631   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3632     SelectionDAG &DAG = DCI.DAG;
3633     if (DAG.isConstantValueOfAnyType(True) &&
3634         !DAG.isConstantValueOfAnyType(False)) {
3635       // Swap cmp + select pair to move constant to false input.
3636       // This will allow using VOPC cndmasks more often.
3637       // select (setcc x, y), k, x -> select (setccinv x, y), x, k
3638 
3639       SDLoc SL(N);
3640       ISD::CondCode NewCC =
3641           getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), LHS.getValueType());
3642 
3643       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3644       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3645     }
3646 
3647     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3648       SDValue MinMax
3649         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3650       // Revisit this node so we can catch min3/max3/med3 patterns.
3651       //DCI.AddToWorklist(MinMax.getNode());
3652       return MinMax;
3653     }
3654   }
3655 
3656   // There's no reason to not do this if the condition has other uses.
3657   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3658 }
3659 
3660 static bool isInv2Pi(const APFloat &APF) {
3661   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3662   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3663   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3664 
3665   return APF.bitwiseIsEqual(KF16) ||
3666          APF.bitwiseIsEqual(KF32) ||
3667          APF.bitwiseIsEqual(KF64);
3668 }
3669 
3670 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3671 // additional cost to negate them.
3672 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3673   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3674     if (C->isZero() && !C->isNegative())
3675       return true;
3676 
3677     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3678       return true;
3679   }
3680 
3681   return false;
3682 }
3683 
3684 static unsigned inverseMinMax(unsigned Opc) {
3685   switch (Opc) {
3686   case ISD::FMAXNUM:
3687     return ISD::FMINNUM;
3688   case ISD::FMINNUM:
3689     return ISD::FMAXNUM;
3690   case ISD::FMAXNUM_IEEE:
3691     return ISD::FMINNUM_IEEE;
3692   case ISD::FMINNUM_IEEE:
3693     return ISD::FMAXNUM_IEEE;
3694   case AMDGPUISD::FMAX_LEGACY:
3695     return AMDGPUISD::FMIN_LEGACY;
3696   case AMDGPUISD::FMIN_LEGACY:
3697     return  AMDGPUISD::FMAX_LEGACY;
3698   default:
3699     llvm_unreachable("invalid min/max opcode");
3700   }
3701 }
3702 
3703 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3704                                                  DAGCombinerInfo &DCI) const {
3705   SelectionDAG &DAG = DCI.DAG;
3706   SDValue N0 = N->getOperand(0);
3707   EVT VT = N->getValueType(0);
3708 
3709   unsigned Opc = N0.getOpcode();
3710 
3711   // If the input has multiple uses and we can either fold the negate down, or
3712   // the other uses cannot, give up. This both prevents unprofitable
3713   // transformations and infinite loops: we won't repeatedly try to fold around
3714   // a negate that has no 'good' form.
3715   if (N0.hasOneUse()) {
3716     // This may be able to fold into the source, but at a code size cost. Don't
3717     // fold if the fold into the user is free.
3718     if (allUsesHaveSourceMods(N, 0))
3719       return SDValue();
3720   } else {
3721     if (fnegFoldsIntoOp(Opc) &&
3722         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3723       return SDValue();
3724   }
3725 
3726   SDLoc SL(N);
3727   switch (Opc) {
3728   case ISD::FADD: {
3729     if (!mayIgnoreSignedZero(N0))
3730       return SDValue();
3731 
3732     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3733     SDValue LHS = N0.getOperand(0);
3734     SDValue RHS = N0.getOperand(1);
3735 
3736     if (LHS.getOpcode() != ISD::FNEG)
3737       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3738     else
3739       LHS = LHS.getOperand(0);
3740 
3741     if (RHS.getOpcode() != ISD::FNEG)
3742       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3743     else
3744       RHS = RHS.getOperand(0);
3745 
3746     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3747     if (Res.getOpcode() != ISD::FADD)
3748       return SDValue(); // Op got folded away.
3749     if (!N0.hasOneUse())
3750       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3751     return Res;
3752   }
3753   case ISD::FMUL:
3754   case AMDGPUISD::FMUL_LEGACY: {
3755     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3756     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3757     SDValue LHS = N0.getOperand(0);
3758     SDValue RHS = N0.getOperand(1);
3759 
3760     if (LHS.getOpcode() == ISD::FNEG)
3761       LHS = LHS.getOperand(0);
3762     else if (RHS.getOpcode() == ISD::FNEG)
3763       RHS = RHS.getOperand(0);
3764     else
3765       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3766 
3767     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3768     if (Res.getOpcode() != Opc)
3769       return SDValue(); // Op got folded away.
3770     if (!N0.hasOneUse())
3771       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3772     return Res;
3773   }
3774   case ISD::FMA:
3775   case ISD::FMAD: {
3776     if (!mayIgnoreSignedZero(N0))
3777       return SDValue();
3778 
3779     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3780     SDValue LHS = N0.getOperand(0);
3781     SDValue MHS = N0.getOperand(1);
3782     SDValue RHS = N0.getOperand(2);
3783 
3784     if (LHS.getOpcode() == ISD::FNEG)
3785       LHS = LHS.getOperand(0);
3786     else if (MHS.getOpcode() == ISD::FNEG)
3787       MHS = MHS.getOperand(0);
3788     else
3789       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3790 
3791     if (RHS.getOpcode() != ISD::FNEG)
3792       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3793     else
3794       RHS = RHS.getOperand(0);
3795 
3796     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3797     if (Res.getOpcode() != Opc)
3798       return SDValue(); // Op got folded away.
3799     if (!N0.hasOneUse())
3800       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3801     return Res;
3802   }
3803   case ISD::FMAXNUM:
3804   case ISD::FMINNUM:
3805   case ISD::FMAXNUM_IEEE:
3806   case ISD::FMINNUM_IEEE:
3807   case AMDGPUISD::FMAX_LEGACY:
3808   case AMDGPUISD::FMIN_LEGACY: {
3809     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3810     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3811     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3812     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3813 
3814     SDValue LHS = N0.getOperand(0);
3815     SDValue RHS = N0.getOperand(1);
3816 
3817     // 0 doesn't have a negated inline immediate.
3818     // TODO: This constant check should be generalized to other operations.
3819     if (isConstantCostlierToNegate(RHS))
3820       return SDValue();
3821 
3822     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3823     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3824     unsigned Opposite = inverseMinMax(Opc);
3825 
3826     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3827     if (Res.getOpcode() != Opposite)
3828       return SDValue(); // Op got folded away.
3829     if (!N0.hasOneUse())
3830       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3831     return Res;
3832   }
3833   case AMDGPUISD::FMED3: {
3834     SDValue Ops[3];
3835     for (unsigned I = 0; I < 3; ++I)
3836       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3837 
3838     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3839     if (Res.getOpcode() != AMDGPUISD::FMED3)
3840       return SDValue(); // Op got folded away.
3841     if (!N0.hasOneUse())
3842       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3843     return Res;
3844   }
3845   case ISD::FP_EXTEND:
3846   case ISD::FTRUNC:
3847   case ISD::FRINT:
3848   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3849   case ISD::FSIN:
3850   case ISD::FCANONICALIZE:
3851   case AMDGPUISD::RCP:
3852   case AMDGPUISD::RCP_LEGACY:
3853   case AMDGPUISD::RCP_IFLAG:
3854   case AMDGPUISD::SIN_HW: {
3855     SDValue CvtSrc = N0.getOperand(0);
3856     if (CvtSrc.getOpcode() == ISD::FNEG) {
3857       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3858       // (fneg (rcp (fneg x))) -> (rcp x)
3859       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3860     }
3861 
3862     if (!N0.hasOneUse())
3863       return SDValue();
3864 
3865     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3866     // (fneg (rcp x)) -> (rcp (fneg x))
3867     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3868     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3869   }
3870   case ISD::FP_ROUND: {
3871     SDValue CvtSrc = N0.getOperand(0);
3872 
3873     if (CvtSrc.getOpcode() == ISD::FNEG) {
3874       // (fneg (fp_round (fneg x))) -> (fp_round x)
3875       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3876                          CvtSrc.getOperand(0), N0.getOperand(1));
3877     }
3878 
3879     if (!N0.hasOneUse())
3880       return SDValue();
3881 
3882     // (fneg (fp_round x)) -> (fp_round (fneg x))
3883     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3884     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3885   }
3886   case ISD::FP16_TO_FP: {
3887     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3888     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3889     // Put the fneg back as a legal source operation that can be matched later.
3890     SDLoc SL(N);
3891 
3892     SDValue Src = N0.getOperand(0);
3893     EVT SrcVT = Src.getValueType();
3894 
3895     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3896     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3897                                   DAG.getConstant(0x8000, SL, SrcVT));
3898     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3899   }
3900   default:
3901     return SDValue();
3902   }
3903 }
3904 
3905 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3906                                                  DAGCombinerInfo &DCI) const {
3907   SelectionDAG &DAG = DCI.DAG;
3908   SDValue N0 = N->getOperand(0);
3909 
3910   if (!N0.hasOneUse())
3911     return SDValue();
3912 
3913   switch (N0.getOpcode()) {
3914   case ISD::FP16_TO_FP: {
3915     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3916     SDLoc SL(N);
3917     SDValue Src = N0.getOperand(0);
3918     EVT SrcVT = Src.getValueType();
3919 
3920     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3921     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3922                                   DAG.getConstant(0x7fff, SL, SrcVT));
3923     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3924   }
3925   default:
3926     return SDValue();
3927   }
3928 }
3929 
3930 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3931                                                 DAGCombinerInfo &DCI) const {
3932   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3933   if (!CFP)
3934     return SDValue();
3935 
3936   // XXX - Should this flush denormals?
3937   const APFloat &Val = CFP->getValueAPF();
3938   APFloat One(Val.getSemantics(), "1.0");
3939   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3940 }
3941 
3942 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3943                                                 DAGCombinerInfo &DCI) const {
3944   SelectionDAG &DAG = DCI.DAG;
3945   SDLoc DL(N);
3946 
3947   switch(N->getOpcode()) {
3948   default:
3949     break;
3950   case ISD::BITCAST: {
3951     EVT DestVT = N->getValueType(0);
3952 
3953     // Push casts through vector builds. This helps avoid emitting a large
3954     // number of copies when materializing floating point vector constants.
3955     //
3956     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3957     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3958     if (DestVT.isVector()) {
3959       SDValue Src = N->getOperand(0);
3960       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3961         EVT SrcVT = Src.getValueType();
3962         unsigned NElts = DestVT.getVectorNumElements();
3963 
3964         if (SrcVT.getVectorNumElements() == NElts) {
3965           EVT DestEltVT = DestVT.getVectorElementType();
3966 
3967           SmallVector<SDValue, 8> CastedElts;
3968           SDLoc SL(N);
3969           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3970             SDValue Elt = Src.getOperand(I);
3971             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3972           }
3973 
3974           return DAG.getBuildVector(DestVT, SL, CastedElts);
3975         }
3976       }
3977     }
3978 
3979     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3980       break;
3981 
3982     // Fold bitcasts of constants.
3983     //
3984     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3985     // TODO: Generalize and move to DAGCombiner
3986     SDValue Src = N->getOperand(0);
3987     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3988       if (Src.getValueType() == MVT::i64) {
3989         SDLoc SL(N);
3990         uint64_t CVal = C->getZExtValue();
3991         SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3992                                  DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3993                                  DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3994         return DAG.getNode(ISD::BITCAST, SL, DestVT, BV);
3995       }
3996     }
3997 
3998     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3999       const APInt &Val = C->getValueAPF().bitcastToAPInt();
4000       SDLoc SL(N);
4001       uint64_t CVal = Val.getZExtValue();
4002       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
4003                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
4004                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
4005 
4006       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
4007     }
4008 
4009     break;
4010   }
4011   case ISD::SHL: {
4012     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4013       break;
4014 
4015     return performShlCombine(N, DCI);
4016   }
4017   case ISD::SRL: {
4018     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4019       break;
4020 
4021     return performSrlCombine(N, DCI);
4022   }
4023   case ISD::SRA: {
4024     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
4025       break;
4026 
4027     return performSraCombine(N, DCI);
4028   }
4029   case ISD::TRUNCATE:
4030     return performTruncateCombine(N, DCI);
4031   case ISD::MUL:
4032     return performMulCombine(N, DCI);
4033   case ISD::MULHS:
4034     return performMulhsCombine(N, DCI);
4035   case ISD::MULHU:
4036     return performMulhuCombine(N, DCI);
4037   case AMDGPUISD::MUL_I24:
4038   case AMDGPUISD::MUL_U24:
4039   case AMDGPUISD::MULHI_I24:
4040   case AMDGPUISD::MULHI_U24: {
4041     if (SDValue V = simplifyI24(N, DCI))
4042       return V;
4043     return SDValue();
4044   }
4045   case AMDGPUISD::MUL_LOHI_I24:
4046   case AMDGPUISD::MUL_LOHI_U24:
4047     return performMulLoHi24Combine(N, DCI);
4048   case ISD::SELECT:
4049     return performSelectCombine(N, DCI);
4050   case ISD::FNEG:
4051     return performFNegCombine(N, DCI);
4052   case ISD::FABS:
4053     return performFAbsCombine(N, DCI);
4054   case AMDGPUISD::BFE_I32:
4055   case AMDGPUISD::BFE_U32: {
4056     assert(!N->getValueType(0).isVector() &&
4057            "Vector handling of BFE not implemented");
4058     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
4059     if (!Width)
4060       break;
4061 
4062     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
4063     if (WidthVal == 0)
4064       return DAG.getConstant(0, DL, MVT::i32);
4065 
4066     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
4067     if (!Offset)
4068       break;
4069 
4070     SDValue BitsFrom = N->getOperand(0);
4071     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
4072 
4073     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
4074 
4075     if (OffsetVal == 0) {
4076       // This is already sign / zero extended, so try to fold away extra BFEs.
4077       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
4078 
4079       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
4080       if (OpSignBits >= SignBits)
4081         return BitsFrom;
4082 
4083       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
4084       if (Signed) {
4085         // This is a sign_extend_inreg. Replace it to take advantage of existing
4086         // DAG Combines. If not eliminated, we will match back to BFE during
4087         // selection.
4088 
4089         // TODO: The sext_inreg of extended types ends, although we can could
4090         // handle them in a single BFE.
4091         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
4092                            DAG.getValueType(SmallVT));
4093       }
4094 
4095       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
4096     }
4097 
4098     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
4099       if (Signed) {
4100         return constantFoldBFE<int32_t>(DAG,
4101                                         CVal->getSExtValue(),
4102                                         OffsetVal,
4103                                         WidthVal,
4104                                         DL);
4105       }
4106 
4107       return constantFoldBFE<uint32_t>(DAG,
4108                                        CVal->getZExtValue(),
4109                                        OffsetVal,
4110                                        WidthVal,
4111                                        DL);
4112     }
4113 
4114     if ((OffsetVal + WidthVal) >= 32 &&
4115         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
4116       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
4117       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
4118                          BitsFrom, ShiftVal);
4119     }
4120 
4121     if (BitsFrom.hasOneUse()) {
4122       APInt Demanded = APInt::getBitsSet(32,
4123                                          OffsetVal,
4124                                          OffsetVal + WidthVal);
4125 
4126       KnownBits Known;
4127       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
4128                                             !DCI.isBeforeLegalizeOps());
4129       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
4130       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
4131           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
4132         DCI.CommitTargetLoweringOpt(TLO);
4133       }
4134     }
4135 
4136     break;
4137   }
4138   case ISD::LOAD:
4139     return performLoadCombine(N, DCI);
4140   case ISD::STORE:
4141     return performStoreCombine(N, DCI);
4142   case AMDGPUISD::RCP:
4143   case AMDGPUISD::RCP_IFLAG:
4144     return performRcpCombine(N, DCI);
4145   case ISD::AssertZext:
4146   case ISD::AssertSext:
4147     return performAssertSZExtCombine(N, DCI);
4148   case ISD::INTRINSIC_WO_CHAIN:
4149     return performIntrinsicWOChainCombine(N, DCI);
4150   }
4151   return SDValue();
4152 }
4153 
4154 //===----------------------------------------------------------------------===//
4155 // Helper functions
4156 //===----------------------------------------------------------------------===//
4157 
4158 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
4159                                                    const TargetRegisterClass *RC,
4160                                                    unsigned Reg, EVT VT,
4161                                                    const SDLoc &SL,
4162                                                    bool RawReg) const {
4163   MachineFunction &MF = DAG.getMachineFunction();
4164   MachineRegisterInfo &MRI = MF.getRegInfo();
4165   unsigned VReg;
4166 
4167   if (!MRI.isLiveIn(Reg)) {
4168     VReg = MRI.createVirtualRegister(RC);
4169     MRI.addLiveIn(Reg, VReg);
4170   } else {
4171     VReg = MRI.getLiveInVirtReg(Reg);
4172   }
4173 
4174   if (RawReg)
4175     return DAG.getRegister(VReg, VT);
4176 
4177   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
4178 }
4179 
4180 // This may be called multiple times, and nothing prevents creating multiple
4181 // objects at the same offset. See if we already defined this object.
4182 static int getOrCreateFixedStackObject(MachineFrameInfo &MFI, unsigned Size,
4183                                        int64_t Offset) {
4184   for (int I = MFI.getObjectIndexBegin(); I < 0; ++I) {
4185     if (MFI.getObjectOffset(I) == Offset) {
4186       assert(MFI.getObjectSize(I) == Size);
4187       return I;
4188     }
4189   }
4190 
4191   return MFI.CreateFixedObject(Size, Offset, true);
4192 }
4193 
4194 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
4195                                                   EVT VT,
4196                                                   const SDLoc &SL,
4197                                                   int64_t Offset) const {
4198   MachineFunction &MF = DAG.getMachineFunction();
4199   MachineFrameInfo &MFI = MF.getFrameInfo();
4200   int FI = getOrCreateFixedStackObject(MFI, VT.getStoreSize(), Offset);
4201 
4202   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4203   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4204 
4205   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4206                      MachineMemOperand::MODereferenceable |
4207                      MachineMemOperand::MOInvariant);
4208 }
4209 
4210 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4211                                                    const SDLoc &SL,
4212                                                    SDValue Chain,
4213                                                    SDValue ArgVal,
4214                                                    int64_t Offset) const {
4215   MachineFunction &MF = DAG.getMachineFunction();
4216   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4217 
4218   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4219   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4220                                MachineMemOperand::MODereferenceable);
4221   return Store;
4222 }
4223 
4224 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4225                                              const TargetRegisterClass *RC,
4226                                              EVT VT, const SDLoc &SL,
4227                                              const ArgDescriptor &Arg) const {
4228   assert(Arg && "Attempting to load missing argument");
4229 
4230   SDValue V = Arg.isRegister() ?
4231     CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL) :
4232     loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4233 
4234   if (!Arg.isMasked())
4235     return V;
4236 
4237   unsigned Mask = Arg.getMask();
4238   unsigned Shift = countTrailingZeros<unsigned>(Mask);
4239   V = DAG.getNode(ISD::SRL, SL, VT, V,
4240                   DAG.getShiftAmountConstant(Shift, VT, SL));
4241   return DAG.getNode(ISD::AND, SL, VT, V,
4242                      DAG.getConstant(Mask >> Shift, SL, VT));
4243 }
4244 
4245 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4246     const MachineFunction &MF, const ImplicitParameter Param) const {
4247   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4248   const AMDGPUSubtarget &ST =
4249       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4250   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4251   const Align Alignment = ST.getAlignmentForImplicitArgPtr();
4252   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4253                        ExplicitArgOffset;
4254   switch (Param) {
4255   case GRID_DIM:
4256     return ArgOffset;
4257   case GRID_OFFSET:
4258     return ArgOffset + 4;
4259   }
4260   llvm_unreachable("unexpected implicit parameter type");
4261 }
4262 
4263 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4264 
4265 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4266   switch ((AMDGPUISD::NodeType)Opcode) {
4267   case AMDGPUISD::FIRST_NUMBER: break;
4268   // AMDIL DAG nodes
4269   NODE_NAME_CASE(UMUL);
4270   NODE_NAME_CASE(BRANCH_COND);
4271 
4272   // AMDGPU DAG nodes
4273   NODE_NAME_CASE(IF)
4274   NODE_NAME_CASE(ELSE)
4275   NODE_NAME_CASE(LOOP)
4276   NODE_NAME_CASE(CALL)
4277   NODE_NAME_CASE(TC_RETURN)
4278   NODE_NAME_CASE(TRAP)
4279   NODE_NAME_CASE(RET_FLAG)
4280   NODE_NAME_CASE(RETURN_TO_EPILOG)
4281   NODE_NAME_CASE(ENDPGM)
4282   NODE_NAME_CASE(DWORDADDR)
4283   NODE_NAME_CASE(FRACT)
4284   NODE_NAME_CASE(SETCC)
4285   NODE_NAME_CASE(SETREG)
4286   NODE_NAME_CASE(DENORM_MODE)
4287   NODE_NAME_CASE(FMA_W_CHAIN)
4288   NODE_NAME_CASE(FMUL_W_CHAIN)
4289   NODE_NAME_CASE(CLAMP)
4290   NODE_NAME_CASE(COS_HW)
4291   NODE_NAME_CASE(SIN_HW)
4292   NODE_NAME_CASE(FMAX_LEGACY)
4293   NODE_NAME_CASE(FMIN_LEGACY)
4294   NODE_NAME_CASE(FMAX3)
4295   NODE_NAME_CASE(SMAX3)
4296   NODE_NAME_CASE(UMAX3)
4297   NODE_NAME_CASE(FMIN3)
4298   NODE_NAME_CASE(SMIN3)
4299   NODE_NAME_CASE(UMIN3)
4300   NODE_NAME_CASE(FMED3)
4301   NODE_NAME_CASE(SMED3)
4302   NODE_NAME_CASE(UMED3)
4303   NODE_NAME_CASE(FDOT2)
4304   NODE_NAME_CASE(URECIP)
4305   NODE_NAME_CASE(DIV_SCALE)
4306   NODE_NAME_CASE(DIV_FMAS)
4307   NODE_NAME_CASE(DIV_FIXUP)
4308   NODE_NAME_CASE(FMAD_FTZ)
4309   NODE_NAME_CASE(TRIG_PREOP)
4310   NODE_NAME_CASE(RCP)
4311   NODE_NAME_CASE(RSQ)
4312   NODE_NAME_CASE(RCP_LEGACY)
4313   NODE_NAME_CASE(RSQ_LEGACY)
4314   NODE_NAME_CASE(RCP_IFLAG)
4315   NODE_NAME_CASE(FMUL_LEGACY)
4316   NODE_NAME_CASE(RSQ_CLAMP)
4317   NODE_NAME_CASE(LDEXP)
4318   NODE_NAME_CASE(FP_CLASS)
4319   NODE_NAME_CASE(DOT4)
4320   NODE_NAME_CASE(CARRY)
4321   NODE_NAME_CASE(BORROW)
4322   NODE_NAME_CASE(BFE_U32)
4323   NODE_NAME_CASE(BFE_I32)
4324   NODE_NAME_CASE(BFI)
4325   NODE_NAME_CASE(BFM)
4326   NODE_NAME_CASE(FFBH_U32)
4327   NODE_NAME_CASE(FFBH_I32)
4328   NODE_NAME_CASE(FFBL_B32)
4329   NODE_NAME_CASE(MUL_U24)
4330   NODE_NAME_CASE(MUL_I24)
4331   NODE_NAME_CASE(MULHI_U24)
4332   NODE_NAME_CASE(MULHI_I24)
4333   NODE_NAME_CASE(MUL_LOHI_U24)
4334   NODE_NAME_CASE(MUL_LOHI_I24)
4335   NODE_NAME_CASE(MAD_U24)
4336   NODE_NAME_CASE(MAD_I24)
4337   NODE_NAME_CASE(MAD_I64_I32)
4338   NODE_NAME_CASE(MAD_U64_U32)
4339   NODE_NAME_CASE(PERM)
4340   NODE_NAME_CASE(TEXTURE_FETCH)
4341   NODE_NAME_CASE(R600_EXPORT)
4342   NODE_NAME_CASE(CONST_ADDRESS)
4343   NODE_NAME_CASE(REGISTER_LOAD)
4344   NODE_NAME_CASE(REGISTER_STORE)
4345   NODE_NAME_CASE(SAMPLE)
4346   NODE_NAME_CASE(SAMPLEB)
4347   NODE_NAME_CASE(SAMPLED)
4348   NODE_NAME_CASE(SAMPLEL)
4349   NODE_NAME_CASE(CVT_F32_UBYTE0)
4350   NODE_NAME_CASE(CVT_F32_UBYTE1)
4351   NODE_NAME_CASE(CVT_F32_UBYTE2)
4352   NODE_NAME_CASE(CVT_F32_UBYTE3)
4353   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4354   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4355   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4356   NODE_NAME_CASE(CVT_PK_I16_I32)
4357   NODE_NAME_CASE(CVT_PK_U16_U32)
4358   NODE_NAME_CASE(FP_TO_FP16)
4359   NODE_NAME_CASE(FP16_ZEXT)
4360   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4361   NODE_NAME_CASE(CONST_DATA_PTR)
4362   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4363   NODE_NAME_CASE(LDS)
4364   NODE_NAME_CASE(DUMMY_CHAIN)
4365   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4366   NODE_NAME_CASE(LOAD_D16_HI)
4367   NODE_NAME_CASE(LOAD_D16_LO)
4368   NODE_NAME_CASE(LOAD_D16_HI_I8)
4369   NODE_NAME_CASE(LOAD_D16_HI_U8)
4370   NODE_NAME_CASE(LOAD_D16_LO_I8)
4371   NODE_NAME_CASE(LOAD_D16_LO_U8)
4372   NODE_NAME_CASE(STORE_MSKOR)
4373   NODE_NAME_CASE(LOAD_CONSTANT)
4374   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4375   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4376   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4377   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4378   NODE_NAME_CASE(DS_ORDERED_COUNT)
4379   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4380   NODE_NAME_CASE(ATOMIC_INC)
4381   NODE_NAME_CASE(ATOMIC_DEC)
4382   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4383   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4384   NODE_NAME_CASE(BUFFER_LOAD)
4385   NODE_NAME_CASE(BUFFER_LOAD_UBYTE)
4386   NODE_NAME_CASE(BUFFER_LOAD_USHORT)
4387   NODE_NAME_CASE(BUFFER_LOAD_BYTE)
4388   NODE_NAME_CASE(BUFFER_LOAD_SHORT)
4389   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4390   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4391   NODE_NAME_CASE(SBUFFER_LOAD)
4392   NODE_NAME_CASE(BUFFER_STORE)
4393   NODE_NAME_CASE(BUFFER_STORE_BYTE)
4394   NODE_NAME_CASE(BUFFER_STORE_SHORT)
4395   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4396   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4397   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4398   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4399   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4400   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4401   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4402   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4403   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4404   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4405   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4406   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4407   NODE_NAME_CASE(BUFFER_ATOMIC_INC)
4408   NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
4409   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4410   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
4411   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)
4412   NODE_NAME_CASE(ATOMIC_PK_FADD)
4413 
4414   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4415   }
4416   return nullptr;
4417 }
4418 
4419 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4420                                               SelectionDAG &DAG, int Enabled,
4421                                               int &RefinementSteps,
4422                                               bool &UseOneConstNR,
4423                                               bool Reciprocal) const {
4424   EVT VT = Operand.getValueType();
4425 
4426   if (VT == MVT::f32) {
4427     RefinementSteps = 0;
4428     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4429   }
4430 
4431   // TODO: There is also f64 rsq instruction, but the documentation is less
4432   // clear on its precision.
4433 
4434   return SDValue();
4435 }
4436 
4437 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4438                                                SelectionDAG &DAG, int Enabled,
4439                                                int &RefinementSteps) const {
4440   EVT VT = Operand.getValueType();
4441 
4442   if (VT == MVT::f32) {
4443     // Reciprocal, < 1 ulp error.
4444     //
4445     // This reciprocal approximation converges to < 0.5 ulp error with one
4446     // newton rhapson performed with two fused multiple adds (FMAs).
4447 
4448     RefinementSteps = 0;
4449     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4450   }
4451 
4452   // TODO: There is also f64 rcp instruction, but the documentation is less
4453   // clear on its precision.
4454 
4455   return SDValue();
4456 }
4457 
4458 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4459     const SDValue Op, KnownBits &Known,
4460     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4461 
4462   Known.resetAll(); // Don't know anything.
4463 
4464   unsigned Opc = Op.getOpcode();
4465 
4466   switch (Opc) {
4467   default:
4468     break;
4469   case AMDGPUISD::CARRY:
4470   case AMDGPUISD::BORROW: {
4471     Known.Zero = APInt::getHighBitsSet(32, 31);
4472     break;
4473   }
4474 
4475   case AMDGPUISD::BFE_I32:
4476   case AMDGPUISD::BFE_U32: {
4477     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4478     if (!CWidth)
4479       return;
4480 
4481     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4482 
4483     if (Opc == AMDGPUISD::BFE_U32)
4484       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4485 
4486     break;
4487   }
4488   case AMDGPUISD::FP_TO_FP16:
4489   case AMDGPUISD::FP16_ZEXT: {
4490     unsigned BitWidth = Known.getBitWidth();
4491 
4492     // High bits are zero.
4493     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4494     break;
4495   }
4496   case AMDGPUISD::MUL_U24:
4497   case AMDGPUISD::MUL_I24: {
4498     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4499     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4500     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4501                       RHSKnown.countMinTrailingZeros();
4502     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4503     // Skip extra check if all bits are known zeros.
4504     if (TrailZ >= 32)
4505       break;
4506 
4507     // Truncate to 24 bits.
4508     LHSKnown = LHSKnown.trunc(24);
4509     RHSKnown = RHSKnown.trunc(24);
4510 
4511     if (Opc == AMDGPUISD::MUL_I24) {
4512       unsigned LHSValBits = 24 - LHSKnown.countMinSignBits();
4513       unsigned RHSValBits = 24 - RHSKnown.countMinSignBits();
4514       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4515       if (MaxValBits >= 32)
4516         break;
4517       bool LHSNegative = LHSKnown.isNegative();
4518       bool LHSNonNegative = LHSKnown.isNonNegative();
4519       bool LHSPositive = LHSKnown.isStrictlyPositive();
4520       bool RHSNegative = RHSKnown.isNegative();
4521       bool RHSNonNegative = RHSKnown.isNonNegative();
4522       bool RHSPositive = RHSKnown.isStrictlyPositive();
4523 
4524       if ((LHSNonNegative && RHSNonNegative) || (LHSNegative && RHSNegative))
4525         Known.Zero.setHighBits(32 - MaxValBits);
4526       else if ((LHSNegative && RHSPositive) || (LHSPositive && RHSNegative))
4527         Known.One.setHighBits(32 - MaxValBits);
4528     } else {
4529       unsigned LHSValBits = 24 - LHSKnown.countMinLeadingZeros();
4530       unsigned RHSValBits = 24 - RHSKnown.countMinLeadingZeros();
4531       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4532       if (MaxValBits >= 32)
4533         break;
4534       Known.Zero.setHighBits(32 - MaxValBits);
4535     }
4536     break;
4537   }
4538   case AMDGPUISD::PERM: {
4539     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4540     if (!CMask)
4541       return;
4542 
4543     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4544     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4545     unsigned Sel = CMask->getZExtValue();
4546 
4547     for (unsigned I = 0; I < 32; I += 8) {
4548       unsigned SelBits = Sel & 0xff;
4549       if (SelBits < 4) {
4550         SelBits *= 8;
4551         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4552         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4553       } else if (SelBits < 7) {
4554         SelBits = (SelBits & 3) * 8;
4555         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4556         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4557       } else if (SelBits == 0x0c) {
4558         Known.Zero |= 0xFFull << I;
4559       } else if (SelBits > 0x0c) {
4560         Known.One |= 0xFFull << I;
4561       }
4562       Sel >>= 8;
4563     }
4564     break;
4565   }
4566   case AMDGPUISD::BUFFER_LOAD_UBYTE:  {
4567     Known.Zero.setHighBits(24);
4568     break;
4569   }
4570   case AMDGPUISD::BUFFER_LOAD_USHORT: {
4571     Known.Zero.setHighBits(16);
4572     break;
4573   }
4574   case AMDGPUISD::LDS: {
4575     auto GA = cast<GlobalAddressSDNode>(Op.getOperand(0).getNode());
4576     unsigned Align = GA->getGlobal()->getAlignment();
4577 
4578     Known.Zero.setHighBits(16);
4579     if (Align)
4580       Known.Zero.setLowBits(Log2_32(Align));
4581     break;
4582   }
4583   case ISD::INTRINSIC_WO_CHAIN: {
4584     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4585     switch (IID) {
4586     case Intrinsic::amdgcn_mbcnt_lo:
4587     case Intrinsic::amdgcn_mbcnt_hi: {
4588       const GCNSubtarget &ST =
4589           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4590       // These return at most the wavefront size - 1.
4591       unsigned Size = Op.getValueType().getSizeInBits();
4592       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4593       break;
4594     }
4595     default:
4596       break;
4597     }
4598   }
4599   }
4600 }
4601 
4602 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4603     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4604     unsigned Depth) const {
4605   switch (Op.getOpcode()) {
4606   case AMDGPUISD::BFE_I32: {
4607     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4608     if (!Width)
4609       return 1;
4610 
4611     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4612     if (!isNullConstant(Op.getOperand(1)))
4613       return SignBits;
4614 
4615     // TODO: Could probably figure something out with non-0 offsets.
4616     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4617     return std::max(SignBits, Op0SignBits);
4618   }
4619 
4620   case AMDGPUISD::BFE_U32: {
4621     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4622     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4623   }
4624 
4625   case AMDGPUISD::CARRY:
4626   case AMDGPUISD::BORROW:
4627     return 31;
4628   case AMDGPUISD::BUFFER_LOAD_BYTE:
4629     return 25;
4630   case AMDGPUISD::BUFFER_LOAD_SHORT:
4631     return 17;
4632   case AMDGPUISD::BUFFER_LOAD_UBYTE:
4633     return 24;
4634   case AMDGPUISD::BUFFER_LOAD_USHORT:
4635     return 16;
4636   case AMDGPUISD::FP_TO_FP16:
4637   case AMDGPUISD::FP16_ZEXT:
4638     return 16;
4639   default:
4640     return 1;
4641   }
4642 }
4643 
4644 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4645                                                         const SelectionDAG &DAG,
4646                                                         bool SNaN,
4647                                                         unsigned Depth) const {
4648   unsigned Opcode = Op.getOpcode();
4649   switch (Opcode) {
4650   case AMDGPUISD::FMIN_LEGACY:
4651   case AMDGPUISD::FMAX_LEGACY: {
4652     if (SNaN)
4653       return true;
4654 
4655     // TODO: Can check no nans on one of the operands for each one, but which
4656     // one?
4657     return false;
4658   }
4659   case AMDGPUISD::FMUL_LEGACY:
4660   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4661     if (SNaN)
4662       return true;
4663     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4664            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4665   }
4666   case AMDGPUISD::FMED3:
4667   case AMDGPUISD::FMIN3:
4668   case AMDGPUISD::FMAX3:
4669   case AMDGPUISD::FMAD_FTZ: {
4670     if (SNaN)
4671       return true;
4672     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4673            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4674            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4675   }
4676   case AMDGPUISD::CVT_F32_UBYTE0:
4677   case AMDGPUISD::CVT_F32_UBYTE1:
4678   case AMDGPUISD::CVT_F32_UBYTE2:
4679   case AMDGPUISD::CVT_F32_UBYTE3:
4680     return true;
4681 
4682   case AMDGPUISD::RCP:
4683   case AMDGPUISD::RSQ:
4684   case AMDGPUISD::RCP_LEGACY:
4685   case AMDGPUISD::RSQ_LEGACY:
4686   case AMDGPUISD::RSQ_CLAMP: {
4687     if (SNaN)
4688       return true;
4689 
4690     // TODO: Need is known positive check.
4691     return false;
4692   }
4693   case AMDGPUISD::LDEXP:
4694   case AMDGPUISD::FRACT: {
4695     if (SNaN)
4696       return true;
4697     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4698   }
4699   case AMDGPUISD::DIV_SCALE:
4700   case AMDGPUISD::DIV_FMAS:
4701   case AMDGPUISD::DIV_FIXUP:
4702   case AMDGPUISD::TRIG_PREOP:
4703     // TODO: Refine on operands.
4704     return SNaN;
4705   case AMDGPUISD::SIN_HW:
4706   case AMDGPUISD::COS_HW: {
4707     // TODO: Need check for infinity
4708     return SNaN;
4709   }
4710   case ISD::INTRINSIC_WO_CHAIN: {
4711     unsigned IntrinsicID
4712       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4713     // TODO: Handle more intrinsics
4714     switch (IntrinsicID) {
4715     case Intrinsic::amdgcn_cubeid:
4716       return true;
4717 
4718     case Intrinsic::amdgcn_frexp_mant: {
4719       if (SNaN)
4720         return true;
4721       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4722     }
4723     case Intrinsic::amdgcn_cvt_pkrtz: {
4724       if (SNaN)
4725         return true;
4726       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4727              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4728     }
4729     case Intrinsic::amdgcn_fdot2:
4730       // TODO: Refine on operand
4731       return SNaN;
4732     default:
4733       return false;
4734     }
4735   }
4736   default:
4737     return false;
4738   }
4739 }
4740 
4741 TargetLowering::AtomicExpansionKind
4742 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4743   switch (RMW->getOperation()) {
4744   case AtomicRMWInst::Nand:
4745   case AtomicRMWInst::FAdd:
4746   case AtomicRMWInst::FSub:
4747     return AtomicExpansionKind::CmpXChg;
4748   default:
4749     return AtomicExpansionKind::None;
4750   }
4751 }
4752