1 //===-- AMDGPUISelLowering.cpp - AMDGPU Common DAG lowering functions -----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 /// \file
10 /// This is the parent TargetLowering class for hardware code gen
11 /// targets.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #include "AMDGPUISelLowering.h"
16 #include "AMDGPU.h"
17 #include "AMDGPUCallLowering.h"
18 #include "AMDGPUFrameLowering.h"
19 #include "AMDGPUSubtarget.h"
20 #include "AMDGPUTargetMachine.h"
21 #include "Utils/AMDGPUBaseInfo.h"
22 #include "R600MachineFunctionInfo.h"
23 #include "SIInstrInfo.h"
24 #include "SIMachineFunctionInfo.h"
25 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
26 #include "llvm/CodeGen/Analysis.h"
27 #include "llvm/CodeGen/CallingConvLower.h"
28 #include "llvm/CodeGen/MachineFunction.h"
29 #include "llvm/CodeGen/MachineRegisterInfo.h"
30 #include "llvm/CodeGen/SelectionDAG.h"
31 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
32 #include "llvm/IR/DataLayout.h"
33 #include "llvm/IR/DiagnosticInfo.h"
34 #include "llvm/Support/KnownBits.h"
35 #include "llvm/Support/MathExtras.h"
36 using namespace llvm;
37 
38 #include "AMDGPUGenCallingConv.inc"
39 
40 static cl::opt<bool> AMDGPUBypassSlowDiv(
41   "amdgpu-bypass-slow-div",
42   cl::desc("Skip 64-bit divide for dynamic 32-bit values"),
43   cl::init(true));
44 
45 // Find a larger type to do a load / store of a vector with.
46 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
47   unsigned StoreSize = VT.getStoreSizeInBits();
48   if (StoreSize <= 32)
49     return EVT::getIntegerVT(Ctx, StoreSize);
50 
51   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
52   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
53 }
54 
55 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
56   EVT VT = Op.getValueType();
57   KnownBits Known = DAG.computeKnownBits(Op);
58   return VT.getSizeInBits() - Known.countMinLeadingZeros();
59 }
60 
61 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
62   EVT VT = Op.getValueType();
63 
64   // In order for this to be a signed 24-bit value, bit 23, must
65   // be a sign bit.
66   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
67 }
68 
69 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
70                                            const AMDGPUSubtarget &STI)
71     : TargetLowering(TM), Subtarget(&STI) {
72   // Lower floating point store/load to integer store/load to reduce the number
73   // of patterns in tablegen.
74   setOperationAction(ISD::LOAD, MVT::f32, Promote);
75   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
76 
77   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
78   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
79 
80   setOperationAction(ISD::LOAD, MVT::v3f32, Promote);
81   AddPromotedToType(ISD::LOAD, MVT::v3f32, MVT::v3i32);
82 
83   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
84   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
85 
86   setOperationAction(ISD::LOAD, MVT::v5f32, Promote);
87   AddPromotedToType(ISD::LOAD, MVT::v5f32, MVT::v5i32);
88 
89   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
90   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
91 
92   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
93   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
94 
95   setOperationAction(ISD::LOAD, MVT::v32f32, Promote);
96   AddPromotedToType(ISD::LOAD, MVT::v32f32, MVT::v32i32);
97 
98   setOperationAction(ISD::LOAD, MVT::i64, Promote);
99   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
100 
101   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
102   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
103 
104   setOperationAction(ISD::LOAD, MVT::f64, Promote);
105   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
106 
107   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
108   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
109 
110   // There are no 64-bit extloads. These should be done as a 32-bit extload and
111   // an extension to 64-bit.
112   for (MVT VT : MVT::integer_valuetypes()) {
113     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
114     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
115     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
116   }
117 
118   for (MVT VT : MVT::integer_valuetypes()) {
119     if (VT == MVT::i64)
120       continue;
121 
122     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
123     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
124     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
125     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
126 
127     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
128     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
129     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
130     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
131 
132     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
133     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
134     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
135     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
136   }
137 
138   for (MVT VT : MVT::integer_fixedlen_vector_valuetypes()) {
139     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
140     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
141     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
142     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
143     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
144     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
145     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
146     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
147     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
148     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v3i16, Expand);
149     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v3i16, Expand);
150     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v3i16, Expand);
151     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
152     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
153     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
154   }
155 
156   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
157   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
158   setLoadExtAction(ISD::EXTLOAD, MVT::v3f32, MVT::v3f16, Expand);
159   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
160   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
161   setLoadExtAction(ISD::EXTLOAD, MVT::v16f32, MVT::v16f16, Expand);
162   setLoadExtAction(ISD::EXTLOAD, MVT::v32f32, MVT::v32f16, Expand);
163 
164   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
165   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
166   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
167   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
168 
169   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
170   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
171   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
172   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
173 
174   setOperationAction(ISD::STORE, MVT::f32, Promote);
175   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
176 
177   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
178   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
179 
180   setOperationAction(ISD::STORE, MVT::v3f32, Promote);
181   AddPromotedToType(ISD::STORE, MVT::v3f32, MVT::v3i32);
182 
183   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
184   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
185 
186   setOperationAction(ISD::STORE, MVT::v5f32, Promote);
187   AddPromotedToType(ISD::STORE, MVT::v5f32, MVT::v5i32);
188 
189   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
190   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
191 
192   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
193   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
194 
195   setOperationAction(ISD::STORE, MVT::v32f32, Promote);
196   AddPromotedToType(ISD::STORE, MVT::v32f32, MVT::v32i32);
197 
198   setOperationAction(ISD::STORE, MVT::i64, Promote);
199   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
200 
201   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
202   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
203 
204   setOperationAction(ISD::STORE, MVT::f64, Promote);
205   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
206 
207   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
208   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
209 
210   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
211   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
212   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
213   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
214 
215   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
216   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
217   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
218   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
219 
220   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
221   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
222   setTruncStoreAction(MVT::v3f32, MVT::v3f16, Expand);
223   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
224   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
225   setTruncStoreAction(MVT::v16f32, MVT::v16f16, Expand);
226   setTruncStoreAction(MVT::v32f32, MVT::v32f16, Expand);
227 
228   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
229   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
230 
231   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
232   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
233 
234   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
235   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
236 
237   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
238   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
239 
240 
241   setOperationAction(ISD::Constant, MVT::i32, Legal);
242   setOperationAction(ISD::Constant, MVT::i64, Legal);
243   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
244   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
245 
246   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
247   setOperationAction(ISD::BRIND, MVT::Other, Expand);
248 
249   // This is totally unsupported, just custom lower to produce an error.
250   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
251 
252   // Library functions.  These default to Expand, but we have instructions
253   // for them.
254   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
255   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
256   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
257   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
258   setOperationAction(ISD::FABS,   MVT::f32, Legal);
259   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
260   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
261   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
262   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
263   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
264 
265   setOperationAction(ISD::FROUND, MVT::f32, Custom);
266   setOperationAction(ISD::FROUND, MVT::f64, Custom);
267 
268   setOperationAction(ISD::FLOG, MVT::f32, Custom);
269   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
270   setOperationAction(ISD::FEXP, MVT::f32, Custom);
271 
272 
273   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
274   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
275 
276   setOperationAction(ISD::FREM, MVT::f32, Custom);
277   setOperationAction(ISD::FREM, MVT::f64, Custom);
278 
279   // Expand to fneg + fadd.
280   setOperationAction(ISD::FSUB, MVT::f64, Expand);
281 
282   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3i32, Custom);
283   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3f32, Custom);
284   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
285   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
286   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5i32, Custom);
287   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5f32, Custom);
288   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
289   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
290   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
291   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
292   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3f32, Custom);
293   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3i32, Custom);
294   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
295   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
296   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5f32, Custom);
297   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5i32, Custom);
298   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
299   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
300   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16f32, Custom);
301   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16i32, Custom);
302   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32f32, Custom);
303   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32i32, Custom);
304 
305   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
306   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
307   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
308 
309   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
310   for (MVT VT : ScalarIntVTs) {
311     // These should use [SU]DIVREM, so set them to expand
312     setOperationAction(ISD::SDIV, VT, Expand);
313     setOperationAction(ISD::UDIV, VT, Expand);
314     setOperationAction(ISD::SREM, VT, Expand);
315     setOperationAction(ISD::UREM, VT, Expand);
316 
317     // GPU does not have divrem function for signed or unsigned.
318     setOperationAction(ISD::SDIVREM, VT, Custom);
319     setOperationAction(ISD::UDIVREM, VT, Custom);
320 
321     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
322     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
323     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
324 
325     setOperationAction(ISD::BSWAP, VT, Expand);
326     setOperationAction(ISD::CTTZ, VT, Expand);
327     setOperationAction(ISD::CTLZ, VT, Expand);
328 
329     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
330     setOperationAction(ISD::ADDC, VT, Legal);
331     setOperationAction(ISD::SUBC, VT, Legal);
332     setOperationAction(ISD::ADDE, VT, Legal);
333     setOperationAction(ISD::SUBE, VT, Legal);
334   }
335 
336   // The hardware supports 32-bit FSHR, but not FSHL.
337   setOperationAction(ISD::FSHR, MVT::i32, Legal);
338 
339   // The hardware supports 32-bit ROTR, but not ROTL.
340   setOperationAction(ISD::ROTL, MVT::i32, Expand);
341   setOperationAction(ISD::ROTL, MVT::i64, Expand);
342   setOperationAction(ISD::ROTR, MVT::i64, Expand);
343 
344   setOperationAction(ISD::MUL, MVT::i64, Expand);
345   setOperationAction(ISD::MULHU, MVT::i64, Expand);
346   setOperationAction(ISD::MULHS, MVT::i64, Expand);
347   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
348   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
349   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
350   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
351   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
352 
353   setOperationAction(ISD::SMIN, MVT::i32, Legal);
354   setOperationAction(ISD::UMIN, MVT::i32, Legal);
355   setOperationAction(ISD::SMAX, MVT::i32, Legal);
356   setOperationAction(ISD::UMAX, MVT::i32, Legal);
357 
358   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
359   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
360   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
361   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
362 
363   static const MVT::SimpleValueType VectorIntTypes[] = {
364     MVT::v2i32, MVT::v3i32, MVT::v4i32, MVT::v5i32
365   };
366 
367   for (MVT VT : VectorIntTypes) {
368     // Expand the following operations for the current type by default.
369     setOperationAction(ISD::ADD,  VT, Expand);
370     setOperationAction(ISD::AND,  VT, Expand);
371     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
372     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
373     setOperationAction(ISD::MUL,  VT, Expand);
374     setOperationAction(ISD::MULHU, VT, Expand);
375     setOperationAction(ISD::MULHS, VT, Expand);
376     setOperationAction(ISD::OR,   VT, Expand);
377     setOperationAction(ISD::SHL,  VT, Expand);
378     setOperationAction(ISD::SRA,  VT, Expand);
379     setOperationAction(ISD::SRL,  VT, Expand);
380     setOperationAction(ISD::ROTL, VT, Expand);
381     setOperationAction(ISD::ROTR, VT, Expand);
382     setOperationAction(ISD::SUB,  VT, Expand);
383     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
384     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
385     setOperationAction(ISD::SDIV, VT, Expand);
386     setOperationAction(ISD::UDIV, VT, Expand);
387     setOperationAction(ISD::SREM, VT, Expand);
388     setOperationAction(ISD::UREM, VT, Expand);
389     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
390     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
391     setOperationAction(ISD::SDIVREM, VT, Custom);
392     setOperationAction(ISD::UDIVREM, VT, Expand);
393     setOperationAction(ISD::SELECT, VT, Expand);
394     setOperationAction(ISD::VSELECT, VT, Expand);
395     setOperationAction(ISD::SELECT_CC, VT, Expand);
396     setOperationAction(ISD::XOR,  VT, Expand);
397     setOperationAction(ISD::BSWAP, VT, Expand);
398     setOperationAction(ISD::CTPOP, VT, Expand);
399     setOperationAction(ISD::CTTZ, VT, Expand);
400     setOperationAction(ISD::CTLZ, VT, Expand);
401     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
402     setOperationAction(ISD::SETCC, VT, Expand);
403   }
404 
405   static const MVT::SimpleValueType FloatVectorTypes[] = {
406      MVT::v2f32, MVT::v3f32, MVT::v4f32, MVT::v5f32
407   };
408 
409   for (MVT VT : FloatVectorTypes) {
410     setOperationAction(ISD::FABS, VT, Expand);
411     setOperationAction(ISD::FMINNUM, VT, Expand);
412     setOperationAction(ISD::FMAXNUM, VT, Expand);
413     setOperationAction(ISD::FADD, VT, Expand);
414     setOperationAction(ISD::FCEIL, VT, Expand);
415     setOperationAction(ISD::FCOS, VT, Expand);
416     setOperationAction(ISD::FDIV, VT, Expand);
417     setOperationAction(ISD::FEXP2, VT, Expand);
418     setOperationAction(ISD::FEXP, VT, Expand);
419     setOperationAction(ISD::FLOG2, VT, Expand);
420     setOperationAction(ISD::FREM, VT, Expand);
421     setOperationAction(ISD::FLOG, VT, Expand);
422     setOperationAction(ISD::FLOG10, VT, Expand);
423     setOperationAction(ISD::FPOW, VT, Expand);
424     setOperationAction(ISD::FFLOOR, VT, Expand);
425     setOperationAction(ISD::FTRUNC, VT, Expand);
426     setOperationAction(ISD::FMUL, VT, Expand);
427     setOperationAction(ISD::FMA, VT, Expand);
428     setOperationAction(ISD::FRINT, VT, Expand);
429     setOperationAction(ISD::FNEARBYINT, VT, Expand);
430     setOperationAction(ISD::FSQRT, VT, Expand);
431     setOperationAction(ISD::FSIN, VT, Expand);
432     setOperationAction(ISD::FSUB, VT, Expand);
433     setOperationAction(ISD::FNEG, VT, Expand);
434     setOperationAction(ISD::VSELECT, VT, Expand);
435     setOperationAction(ISD::SELECT_CC, VT, Expand);
436     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
437     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
438     setOperationAction(ISD::SETCC, VT, Expand);
439     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
440   }
441 
442   // This causes using an unrolled select operation rather than expansion with
443   // bit operations. This is in general better, but the alternative using BFI
444   // instructions may be better if the select sources are SGPRs.
445   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
446   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
447 
448   setOperationAction(ISD::SELECT, MVT::v3f32, Promote);
449   AddPromotedToType(ISD::SELECT, MVT::v3f32, MVT::v3i32);
450 
451   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
452   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
453 
454   setOperationAction(ISD::SELECT, MVT::v5f32, Promote);
455   AddPromotedToType(ISD::SELECT, MVT::v5f32, MVT::v5i32);
456 
457   // There are no libcalls of any kind.
458   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
459     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
460 
461   setSchedulingPreference(Sched::RegPressure);
462   setJumpIsExpensive(true);
463 
464   // FIXME: This is only partially true. If we have to do vector compares, any
465   // SGPR pair can be a condition register. If we have a uniform condition, we
466   // are better off doing SALU operations, where there is only one SCC. For now,
467   // we don't have a way of knowing during instruction selection if a condition
468   // will be uniform and we always use vector compares. Assume we are using
469   // vector compares until that is fixed.
470   setHasMultipleConditionRegisters(true);
471 
472   setMinCmpXchgSizeInBits(32);
473   setSupportsUnalignedAtomics(false);
474 
475   PredictableSelectIsExpensive = false;
476 
477   // We want to find all load dependencies for long chains of stores to enable
478   // merging into very wide vectors. The problem is with vectors with > 4
479   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
480   // vectors are a legal type, even though we have to split the loads
481   // usually. When we can more precisely specify load legality per address
482   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
483   // smarter so that they can figure out what to do in 2 iterations without all
484   // N > 4 stores on the same chain.
485   GatherAllAliasesMaxDepth = 16;
486 
487   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
488   // about these during lowering.
489   MaxStoresPerMemcpy  = 0xffffffff;
490   MaxStoresPerMemmove = 0xffffffff;
491   MaxStoresPerMemset  = 0xffffffff;
492 
493   // The expansion for 64-bit division is enormous.
494   if (AMDGPUBypassSlowDiv)
495     addBypassSlowDiv(64, 32);
496 
497   setTargetDAGCombine(ISD::BITCAST);
498   setTargetDAGCombine(ISD::SHL);
499   setTargetDAGCombine(ISD::SRA);
500   setTargetDAGCombine(ISD::SRL);
501   setTargetDAGCombine(ISD::TRUNCATE);
502   setTargetDAGCombine(ISD::MUL);
503   setTargetDAGCombine(ISD::MULHU);
504   setTargetDAGCombine(ISD::MULHS);
505   setTargetDAGCombine(ISD::SELECT);
506   setTargetDAGCombine(ISD::SELECT_CC);
507   setTargetDAGCombine(ISD::STORE);
508   setTargetDAGCombine(ISD::FADD);
509   setTargetDAGCombine(ISD::FSUB);
510   setTargetDAGCombine(ISD::FNEG);
511   setTargetDAGCombine(ISD::FABS);
512   setTargetDAGCombine(ISD::AssertZext);
513   setTargetDAGCombine(ISD::AssertSext);
514   setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
515 }
516 
517 //===----------------------------------------------------------------------===//
518 // Target Information
519 //===----------------------------------------------------------------------===//
520 
521 LLVM_READNONE
522 static bool fnegFoldsIntoOp(unsigned Opc) {
523   switch (Opc) {
524   case ISD::FADD:
525   case ISD::FSUB:
526   case ISD::FMUL:
527   case ISD::FMA:
528   case ISD::FMAD:
529   case ISD::FMINNUM:
530   case ISD::FMAXNUM:
531   case ISD::FMINNUM_IEEE:
532   case ISD::FMAXNUM_IEEE:
533   case ISD::FSIN:
534   case ISD::FTRUNC:
535   case ISD::FRINT:
536   case ISD::FNEARBYINT:
537   case ISD::FCANONICALIZE:
538   case AMDGPUISD::RCP:
539   case AMDGPUISD::RCP_LEGACY:
540   case AMDGPUISD::RCP_IFLAG:
541   case AMDGPUISD::SIN_HW:
542   case AMDGPUISD::FMUL_LEGACY:
543   case AMDGPUISD::FMIN_LEGACY:
544   case AMDGPUISD::FMAX_LEGACY:
545   case AMDGPUISD::FMED3:
546     return true;
547   default:
548     return false;
549   }
550 }
551 
552 /// \p returns true if the operation will definitely need to use a 64-bit
553 /// encoding, and thus will use a VOP3 encoding regardless of the source
554 /// modifiers.
555 LLVM_READONLY
556 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
557   return N->getNumOperands() > 2 || VT == MVT::f64;
558 }
559 
560 // Most FP instructions support source modifiers, but this could be refined
561 // slightly.
562 LLVM_READONLY
563 static bool hasSourceMods(const SDNode *N) {
564   if (isa<MemSDNode>(N))
565     return false;
566 
567   switch (N->getOpcode()) {
568   case ISD::CopyToReg:
569   case ISD::SELECT:
570   case ISD::FDIV:
571   case ISD::FREM:
572   case ISD::INLINEASM:
573   case ISD::INLINEASM_BR:
574   case AMDGPUISD::DIV_SCALE:
575   case ISD::INTRINSIC_W_CHAIN:
576 
577   // TODO: Should really be looking at the users of the bitcast. These are
578   // problematic because bitcasts are used to legalize all stores to integer
579   // types.
580   case ISD::BITCAST:
581     return false;
582   case ISD::INTRINSIC_WO_CHAIN: {
583     switch (cast<ConstantSDNode>(N->getOperand(0))->getZExtValue()) {
584     case Intrinsic::amdgcn_interp_p1:
585     case Intrinsic::amdgcn_interp_p2:
586     case Intrinsic::amdgcn_interp_mov:
587     case Intrinsic::amdgcn_interp_p1_f16:
588     case Intrinsic::amdgcn_interp_p2_f16:
589       return false;
590     default:
591       return true;
592     }
593   }
594   default:
595     return true;
596   }
597 }
598 
599 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
600                                                  unsigned CostThreshold) {
601   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
602   // it is truly free to use a source modifier in all cases. If there are
603   // multiple users but for each one will necessitate using VOP3, there will be
604   // a code size increase. Try to avoid increasing code size unless we know it
605   // will save on the instruction count.
606   unsigned NumMayIncreaseSize = 0;
607   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
608 
609   // XXX - Should this limit number of uses to check?
610   for (const SDNode *U : N->uses()) {
611     if (!hasSourceMods(U))
612       return false;
613 
614     if (!opMustUseVOP3Encoding(U, VT)) {
615       if (++NumMayIncreaseSize > CostThreshold)
616         return false;
617     }
618   }
619 
620   return true;
621 }
622 
623 EVT AMDGPUTargetLowering::getTypeForExtReturn(LLVMContext &Context, EVT VT,
624                                               ISD::NodeType ExtendKind) const {
625   assert(!VT.isVector() && "only scalar expected");
626 
627   // Round to the next multiple of 32-bits.
628   unsigned Size = VT.getSizeInBits();
629   if (Size <= 32)
630     return MVT::i32;
631   return EVT::getIntegerVT(Context, 32 * ((Size + 31) / 32));
632 }
633 
634 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
635   return MVT::i32;
636 }
637 
638 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
639   return true;
640 }
641 
642 // The backend supports 32 and 64 bit floating point immediates.
643 // FIXME: Why are we reporting vectors of FP immediates as legal?
644 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
645                                         bool ForCodeSize) const {
646   EVT ScalarVT = VT.getScalarType();
647   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
648          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
649 }
650 
651 // We don't want to shrink f64 / f32 constants.
652 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
653   EVT ScalarVT = VT.getScalarType();
654   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
655 }
656 
657 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
658                                                  ISD::LoadExtType ExtTy,
659                                                  EVT NewVT) const {
660   // TODO: This may be worth removing. Check regression tests for diffs.
661   if (!TargetLoweringBase::shouldReduceLoadWidth(N, ExtTy, NewVT))
662     return false;
663 
664   unsigned NewSize = NewVT.getStoreSizeInBits();
665 
666   // If we are reducing to a 32-bit load or a smaller multi-dword load,
667   // this is always better.
668   if (NewSize >= 32)
669     return true;
670 
671   EVT OldVT = N->getValueType(0);
672   unsigned OldSize = OldVT.getStoreSizeInBits();
673 
674   MemSDNode *MN = cast<MemSDNode>(N);
675   unsigned AS = MN->getAddressSpace();
676   // Do not shrink an aligned scalar load to sub-dword.
677   // Scalar engine cannot do sub-dword loads.
678   if (OldSize >= 32 && NewSize < 32 && MN->getAlignment() >= 4 &&
679       (AS == AMDGPUAS::CONSTANT_ADDRESS ||
680        AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT ||
681        (isa<LoadSDNode>(N) &&
682         AS == AMDGPUAS::GLOBAL_ADDRESS && MN->isInvariant())) &&
683       AMDGPUInstrInfo::isUniformMMO(MN->getMemOperand()))
684     return false;
685 
686   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
687   // extloads, so doing one requires using a buffer_load. In cases where we
688   // still couldn't use a scalar load, using the wider load shouldn't really
689   // hurt anything.
690 
691   // If the old size already had to be an extload, there's no harm in continuing
692   // to reduce the width.
693   return (OldSize < 32);
694 }
695 
696 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy, EVT CastTy,
697                                                    const SelectionDAG &DAG,
698                                                    const MachineMemOperand &MMO) const {
699 
700   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
701 
702   if (LoadTy.getScalarType() == MVT::i32)
703     return false;
704 
705   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
706   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
707 
708   if ((LScalarSize >= CastScalarSize) && (CastScalarSize < 32))
709     return false;
710 
711   bool Fast = false;
712   return allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
713                                         CastTy, MMO, &Fast) &&
714          Fast;
715 }
716 
717 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
718 // profitable with the expansion for 64-bit since it's generally good to
719 // speculate things.
720 // FIXME: These should really have the size as a parameter.
721 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
722   return true;
723 }
724 
725 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
726   return true;
727 }
728 
729 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
730   switch (N->getOpcode()) {
731     default:
732     return false;
733     case ISD::EntryToken:
734     case ISD::TokenFactor:
735       return true;
736     case ISD::INTRINSIC_WO_CHAIN:
737     {
738       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
739       switch (IntrID) {
740         default:
741         return false;
742         case Intrinsic::amdgcn_readfirstlane:
743         case Intrinsic::amdgcn_readlane:
744           return true;
745       }
746     }
747     break;
748     case ISD::LOAD:
749     {
750       if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
751           AMDGPUAS::CONSTANT_ADDRESS_32BIT)
752         return true;
753       return false;
754     }
755     break;
756   }
757 }
758 
759 TargetLowering::NegatibleCost
760 AMDGPUTargetLowering::getNegatibleCost(SDValue Op, SelectionDAG &DAG,
761                                        bool LegalOperations, bool ForCodeSize,
762                                        unsigned Depth) const {
763   switch (Op.getOpcode()) {
764   case ISD::FMA:
765   case ISD::FMAD: {
766     // Negating a fma is not free if it has users without source mods.
767     if (!allUsesHaveSourceMods(Op.getNode()))
768       return NegatibleCost::Expensive;
769     break;
770   }
771   default:
772     break;
773   }
774 
775   return TargetLowering::getNegatibleCost(Op, DAG, LegalOperations, ForCodeSize,
776                                           Depth);
777 }
778 
779 //===---------------------------------------------------------------------===//
780 // Target Properties
781 //===---------------------------------------------------------------------===//
782 
783 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
784   assert(VT.isFloatingPoint());
785 
786   // Packed operations do not have a fabs modifier.
787   return VT == MVT::f32 || VT == MVT::f64 ||
788          (Subtarget->has16BitInsts() && VT == MVT::f16);
789 }
790 
791 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
792   assert(VT.isFloatingPoint());
793   return VT == MVT::f32 || VT == MVT::f64 ||
794          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
795          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
796 }
797 
798 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
799                                                          unsigned NumElem,
800                                                          unsigned AS) const {
801   return true;
802 }
803 
804 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
805   // There are few operations which truly have vector input operands. Any vector
806   // operation is going to involve operations on each component, and a
807   // build_vector will be a copy per element, so it always makes sense to use a
808   // build_vector input in place of the extracted element to avoid a copy into a
809   // super register.
810   //
811   // We should probably only do this if all users are extracts only, but this
812   // should be the common case.
813   return true;
814 }
815 
816 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
817   // Truncate is just accessing a subregister.
818 
819   unsigned SrcSize = Source.getSizeInBits();
820   unsigned DestSize = Dest.getSizeInBits();
821 
822   return DestSize < SrcSize && DestSize % 32 == 0 ;
823 }
824 
825 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
826   // Truncate is just accessing a subregister.
827 
828   unsigned SrcSize = Source->getScalarSizeInBits();
829   unsigned DestSize = Dest->getScalarSizeInBits();
830 
831   if (DestSize== 16 && Subtarget->has16BitInsts())
832     return SrcSize >= 32;
833 
834   return DestSize < SrcSize && DestSize % 32 == 0;
835 }
836 
837 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
838   unsigned SrcSize = Src->getScalarSizeInBits();
839   unsigned DestSize = Dest->getScalarSizeInBits();
840 
841   if (SrcSize == 16 && Subtarget->has16BitInsts())
842     return DestSize >= 32;
843 
844   return SrcSize == 32 && DestSize == 64;
845 }
846 
847 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
848   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
849   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
850   // this will enable reducing 64-bit operations the 32-bit, which is always
851   // good.
852 
853   if (Src == MVT::i16)
854     return Dest == MVT::i32 ||Dest == MVT::i64 ;
855 
856   return Src == MVT::i32 && Dest == MVT::i64;
857 }
858 
859 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
860   return isZExtFree(Val.getValueType(), VT2);
861 }
862 
863 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
864   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
865   // limited number of native 64-bit operations. Shrinking an operation to fit
866   // in a single 32-bit register should always be helpful. As currently used,
867   // this is much less general than the name suggests, and is only used in
868   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
869   // not profitable, and may actually be harmful.
870   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
871 }
872 
873 //===---------------------------------------------------------------------===//
874 // TargetLowering Callbacks
875 //===---------------------------------------------------------------------===//
876 
877 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
878                                                   bool IsVarArg) {
879   switch (CC) {
880   case CallingConv::AMDGPU_VS:
881   case CallingConv::AMDGPU_GS:
882   case CallingConv::AMDGPU_PS:
883   case CallingConv::AMDGPU_CS:
884   case CallingConv::AMDGPU_HS:
885   case CallingConv::AMDGPU_ES:
886   case CallingConv::AMDGPU_LS:
887     return CC_AMDGPU;
888   case CallingConv::C:
889   case CallingConv::Fast:
890   case CallingConv::Cold:
891     return CC_AMDGPU_Func;
892   case CallingConv::AMDGPU_KERNEL:
893   case CallingConv::SPIR_KERNEL:
894   default:
895     report_fatal_error("Unsupported calling convention for call");
896   }
897 }
898 
899 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
900                                                     bool IsVarArg) {
901   switch (CC) {
902   case CallingConv::AMDGPU_KERNEL:
903   case CallingConv::SPIR_KERNEL:
904     llvm_unreachable("kernels should not be handled here");
905   case CallingConv::AMDGPU_VS:
906   case CallingConv::AMDGPU_GS:
907   case CallingConv::AMDGPU_PS:
908   case CallingConv::AMDGPU_CS:
909   case CallingConv::AMDGPU_HS:
910   case CallingConv::AMDGPU_ES:
911   case CallingConv::AMDGPU_LS:
912     return RetCC_SI_Shader;
913   case CallingConv::C:
914   case CallingConv::Fast:
915   case CallingConv::Cold:
916     return RetCC_AMDGPU_Func;
917   default:
918     report_fatal_error("Unsupported calling convention.");
919   }
920 }
921 
922 /// The SelectionDAGBuilder will automatically promote function arguments
923 /// with illegal types.  However, this does not work for the AMDGPU targets
924 /// since the function arguments are stored in memory as these illegal types.
925 /// In order to handle this properly we need to get the original types sizes
926 /// from the LLVM IR Function and fixup the ISD:InputArg values before
927 /// passing them to AnalyzeFormalArguments()
928 
929 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
930 /// input values across multiple registers.  Each item in the Ins array
931 /// represents a single value that will be stored in registers.  Ins[x].VT is
932 /// the value type of the value that will be stored in the register, so
933 /// whatever SDNode we lower the argument to needs to be this type.
934 ///
935 /// In order to correctly lower the arguments we need to know the size of each
936 /// argument.  Since Ins[x].VT gives us the size of the register that will
937 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
938 /// for the orignal function argument so that we can deduce the correct memory
939 /// type to use for Ins[x].  In most cases the correct memory type will be
940 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
941 /// we have a kernel argument of type v8i8, this argument will be split into
942 /// 8 parts and each part will be represented by its own item in the Ins array.
943 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
944 /// the argument before it was split.  From this, we deduce that the memory type
945 /// for each individual part is i8.  We pass the memory type as LocVT to the
946 /// calling convention analysis function and the register type (Ins[x].VT) as
947 /// the ValVT.
948 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
949   CCState &State,
950   const SmallVectorImpl<ISD::InputArg> &Ins) const {
951   const MachineFunction &MF = State.getMachineFunction();
952   const Function &Fn = MF.getFunction();
953   LLVMContext &Ctx = Fn.getParent()->getContext();
954   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
955   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
956   CallingConv::ID CC = Fn.getCallingConv();
957 
958   unsigned MaxAlign = 1;
959   uint64_t ExplicitArgOffset = 0;
960   const DataLayout &DL = Fn.getParent()->getDataLayout();
961 
962   unsigned InIndex = 0;
963 
964   for (const Argument &Arg : Fn.args()) {
965     Type *BaseArgTy = Arg.getType();
966     unsigned Align = DL.getABITypeAlignment(BaseArgTy);
967     MaxAlign = std::max(Align, MaxAlign);
968     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
969 
970     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Align) + ExplicitOffset;
971     ExplicitArgOffset = alignTo(ExplicitArgOffset, Align) + AllocSize;
972 
973     // We're basically throwing away everything passed into us and starting over
974     // to get accurate in-memory offsets. The "PartOffset" is completely useless
975     // to us as computed in Ins.
976     //
977     // We also need to figure out what type legalization is trying to do to get
978     // the correct memory offsets.
979 
980     SmallVector<EVT, 16> ValueVTs;
981     SmallVector<uint64_t, 16> Offsets;
982     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
983 
984     for (unsigned Value = 0, NumValues = ValueVTs.size();
985          Value != NumValues; ++Value) {
986       uint64_t BasePartOffset = Offsets[Value];
987 
988       EVT ArgVT = ValueVTs[Value];
989       EVT MemVT = ArgVT;
990       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
991       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
992 
993       if (NumRegs == 1) {
994         // This argument is not split, so the IR type is the memory type.
995         if (ArgVT.isExtended()) {
996           // We have an extended type, like i24, so we should just use the
997           // register type.
998           MemVT = RegisterVT;
999         } else {
1000           MemVT = ArgVT;
1001         }
1002       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
1003                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
1004         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
1005         // We have a vector value which has been split into a vector with
1006         // the same scalar type, but fewer elements.  This should handle
1007         // all the floating-point vector types.
1008         MemVT = RegisterVT;
1009       } else if (ArgVT.isVector() &&
1010                  ArgVT.getVectorNumElements() == NumRegs) {
1011         // This arg has been split so that each element is stored in a separate
1012         // register.
1013         MemVT = ArgVT.getScalarType();
1014       } else if (ArgVT.isExtended()) {
1015         // We have an extended type, like i65.
1016         MemVT = RegisterVT;
1017       } else {
1018         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
1019         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
1020         if (RegisterVT.isInteger()) {
1021           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1022         } else if (RegisterVT.isVector()) {
1023           assert(!RegisterVT.getScalarType().isFloatingPoint());
1024           unsigned NumElements = RegisterVT.getVectorNumElements();
1025           assert(MemoryBits % NumElements == 0);
1026           // This vector type has been split into another vector type with
1027           // a different elements size.
1028           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1029                                            MemoryBits / NumElements);
1030           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1031         } else {
1032           llvm_unreachable("cannot deduce memory type.");
1033         }
1034       }
1035 
1036       // Convert one element vectors to scalar.
1037       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1038         MemVT = MemVT.getScalarType();
1039 
1040       // Round up vec3/vec5 argument.
1041       if (MemVT.isVector() && !MemVT.isPow2VectorType()) {
1042         assert(MemVT.getVectorNumElements() == 3 ||
1043                MemVT.getVectorNumElements() == 5);
1044         MemVT = MemVT.getPow2VectorType(State.getContext());
1045       } else if (!MemVT.isSimple() && !MemVT.isVector()) {
1046         MemVT = MemVT.getRoundIntegerType(State.getContext());
1047       }
1048 
1049       unsigned PartOffset = 0;
1050       for (unsigned i = 0; i != NumRegs; ++i) {
1051         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1052                                                BasePartOffset + PartOffset,
1053                                                MemVT.getSimpleVT(),
1054                                                CCValAssign::Full));
1055         PartOffset += MemVT.getStoreSize();
1056       }
1057     }
1058   }
1059 }
1060 
1061 SDValue AMDGPUTargetLowering::LowerReturn(
1062   SDValue Chain, CallingConv::ID CallConv,
1063   bool isVarArg,
1064   const SmallVectorImpl<ISD::OutputArg> &Outs,
1065   const SmallVectorImpl<SDValue> &OutVals,
1066   const SDLoc &DL, SelectionDAG &DAG) const {
1067   // FIXME: Fails for r600 tests
1068   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1069   // "wave terminate should not have return values");
1070   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1071 }
1072 
1073 //===---------------------------------------------------------------------===//
1074 // Target specific lowering
1075 //===---------------------------------------------------------------------===//
1076 
1077 /// Selects the correct CCAssignFn for a given CallingConvention value.
1078 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1079                                                     bool IsVarArg) {
1080   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1081 }
1082 
1083 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1084                                                       bool IsVarArg) {
1085   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1086 }
1087 
1088 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1089                                                   SelectionDAG &DAG,
1090                                                   MachineFrameInfo &MFI,
1091                                                   int ClobberedFI) const {
1092   SmallVector<SDValue, 8> ArgChains;
1093   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1094   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1095 
1096   // Include the original chain at the beginning of the list. When this is
1097   // used by target LowerCall hooks, this helps legalize find the
1098   // CALLSEQ_BEGIN node.
1099   ArgChains.push_back(Chain);
1100 
1101   // Add a chain value for each stack argument corresponding
1102   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1103                             UE = DAG.getEntryNode().getNode()->use_end();
1104        U != UE; ++U) {
1105     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1106       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1107         if (FI->getIndex() < 0) {
1108           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1109           int64_t InLastByte = InFirstByte;
1110           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1111 
1112           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1113               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1114             ArgChains.push_back(SDValue(L, 1));
1115         }
1116       }
1117     }
1118   }
1119 
1120   // Build a tokenfactor for all the chains.
1121   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1122 }
1123 
1124 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1125                                                  SmallVectorImpl<SDValue> &InVals,
1126                                                  StringRef Reason) const {
1127   SDValue Callee = CLI.Callee;
1128   SelectionDAG &DAG = CLI.DAG;
1129 
1130   const Function &Fn = DAG.getMachineFunction().getFunction();
1131 
1132   StringRef FuncName("<unknown>");
1133 
1134   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1135     FuncName = G->getSymbol();
1136   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1137     FuncName = G->getGlobal()->getName();
1138 
1139   DiagnosticInfoUnsupported NoCalls(
1140     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1141   DAG.getContext()->diagnose(NoCalls);
1142 
1143   if (!CLI.IsTailCall) {
1144     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1145       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1146   }
1147 
1148   return DAG.getEntryNode();
1149 }
1150 
1151 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1152                                         SmallVectorImpl<SDValue> &InVals) const {
1153   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1154 }
1155 
1156 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1157                                                       SelectionDAG &DAG) const {
1158   const Function &Fn = DAG.getMachineFunction().getFunction();
1159 
1160   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1161                                             SDLoc(Op).getDebugLoc());
1162   DAG.getContext()->diagnose(NoDynamicAlloca);
1163   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1164   return DAG.getMergeValues(Ops, SDLoc());
1165 }
1166 
1167 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1168                                              SelectionDAG &DAG) const {
1169   switch (Op.getOpcode()) {
1170   default:
1171     Op->print(errs(), &DAG);
1172     llvm_unreachable("Custom lowering code for this"
1173                      "instruction is not implemented yet!");
1174     break;
1175   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1176   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1177   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1178   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1179   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1180   case ISD::FREM: return LowerFREM(Op, DAG);
1181   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1182   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1183   case ISD::FRINT: return LowerFRINT(Op, DAG);
1184   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1185   case ISD::FROUND: return LowerFROUND(Op, DAG);
1186   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1187   case ISD::FLOG:
1188     return LowerFLOG(Op, DAG, 1.0F / numbers::log2ef);
1189   case ISD::FLOG10:
1190     return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
1191   case ISD::FEXP:
1192     return lowerFEXP(Op, DAG);
1193   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1194   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1195   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1196   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1197   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1198   case ISD::CTTZ:
1199   case ISD::CTTZ_ZERO_UNDEF:
1200   case ISD::CTLZ:
1201   case ISD::CTLZ_ZERO_UNDEF:
1202     return LowerCTLZ_CTTZ(Op, DAG);
1203   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1204   }
1205   return Op;
1206 }
1207 
1208 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1209                                               SmallVectorImpl<SDValue> &Results,
1210                                               SelectionDAG &DAG) const {
1211   switch (N->getOpcode()) {
1212   case ISD::SIGN_EXTEND_INREG:
1213     // Different parts of legalization seem to interpret which type of
1214     // sign_extend_inreg is the one to check for custom lowering. The extended
1215     // from type is what really matters, but some places check for custom
1216     // lowering of the result type. This results in trying to use
1217     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1218     // nothing here and let the illegal result integer be handled normally.
1219     return;
1220   default:
1221     return;
1222   }
1223 }
1224 
1225 bool AMDGPUTargetLowering::hasDefinedInitializer(const GlobalValue *GV) {
1226   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1227   if (!GVar || !GVar->hasInitializer())
1228     return false;
1229 
1230   return !isa<UndefValue>(GVar->getInitializer());
1231 }
1232 
1233 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1234                                                  SDValue Op,
1235                                                  SelectionDAG &DAG) const {
1236 
1237   const DataLayout &DL = DAG.getDataLayout();
1238   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1239   const GlobalValue *GV = G->getGlobal();
1240 
1241   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1242       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1243     if (!MFI->isEntryFunction()) {
1244       SDLoc DL(Op);
1245       const Function &Fn = DAG.getMachineFunction().getFunction();
1246       DiagnosticInfoUnsupported BadLDSDecl(
1247         Fn, "local memory global used by non-kernel function",
1248         DL.getDebugLoc(), DS_Warning);
1249       DAG.getContext()->diagnose(BadLDSDecl);
1250 
1251       // We currently don't have a way to correctly allocate LDS objects that
1252       // aren't directly associated with a kernel. We do force inlining of
1253       // functions that use local objects. However, if these dead functions are
1254       // not eliminated, we don't want a compile time error. Just emit a warning
1255       // and a trap, since there should be no callable path here.
1256       SDValue Trap = DAG.getNode(ISD::TRAP, DL, MVT::Other, DAG.getEntryNode());
1257       SDValue OutputChain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other,
1258                                         Trap, DAG.getRoot());
1259       DAG.setRoot(OutputChain);
1260       return DAG.getUNDEF(Op.getValueType());
1261     }
1262 
1263     // XXX: What does the value of G->getOffset() mean?
1264     assert(G->getOffset() == 0 &&
1265          "Do not know what to do with an non-zero offset");
1266 
1267     // TODO: We could emit code to handle the initialization somewhere.
1268     if (!hasDefinedInitializer(GV)) {
1269       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1270       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1271     }
1272   }
1273 
1274   const Function &Fn = DAG.getMachineFunction().getFunction();
1275   DiagnosticInfoUnsupported BadInit(
1276       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1277   DAG.getContext()->diagnose(BadInit);
1278   return SDValue();
1279 }
1280 
1281 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1282                                                   SelectionDAG &DAG) const {
1283   SmallVector<SDValue, 8> Args;
1284 
1285   EVT VT = Op.getValueType();
1286   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1287     SDLoc SL(Op);
1288     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1289     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1290 
1291     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1292     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1293   }
1294 
1295   for (const SDUse &U : Op->ops())
1296     DAG.ExtractVectorElements(U.get(), Args);
1297 
1298   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1299 }
1300 
1301 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1302                                                      SelectionDAG &DAG) const {
1303 
1304   SmallVector<SDValue, 8> Args;
1305   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1306   EVT VT = Op.getValueType();
1307   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1308                             VT.getVectorNumElements());
1309 
1310   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1311 }
1312 
1313 /// Generate Min/Max node
1314 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1315                                                    SDValue LHS, SDValue RHS,
1316                                                    SDValue True, SDValue False,
1317                                                    SDValue CC,
1318                                                    DAGCombinerInfo &DCI) const {
1319   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1320     return SDValue();
1321 
1322   SelectionDAG &DAG = DCI.DAG;
1323   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1324   switch (CCOpcode) {
1325   case ISD::SETOEQ:
1326   case ISD::SETONE:
1327   case ISD::SETUNE:
1328   case ISD::SETNE:
1329   case ISD::SETUEQ:
1330   case ISD::SETEQ:
1331   case ISD::SETFALSE:
1332   case ISD::SETFALSE2:
1333   case ISD::SETTRUE:
1334   case ISD::SETTRUE2:
1335   case ISD::SETUO:
1336   case ISD::SETO:
1337     break;
1338   case ISD::SETULE:
1339   case ISD::SETULT: {
1340     if (LHS == True)
1341       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1342     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1343   }
1344   case ISD::SETOLE:
1345   case ISD::SETOLT:
1346   case ISD::SETLE:
1347   case ISD::SETLT: {
1348     // Ordered. Assume ordered for undefined.
1349 
1350     // Only do this after legalization to avoid interfering with other combines
1351     // which might occur.
1352     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1353         !DCI.isCalledByLegalizer())
1354       return SDValue();
1355 
1356     // We need to permute the operands to get the correct NaN behavior. The
1357     // selected operand is the second one based on the failing compare with NaN,
1358     // so permute it based on the compare type the hardware uses.
1359     if (LHS == True)
1360       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1361     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1362   }
1363   case ISD::SETUGE:
1364   case ISD::SETUGT: {
1365     if (LHS == True)
1366       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1367     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1368   }
1369   case ISD::SETGT:
1370   case ISD::SETGE:
1371   case ISD::SETOGE:
1372   case ISD::SETOGT: {
1373     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1374         !DCI.isCalledByLegalizer())
1375       return SDValue();
1376 
1377     if (LHS == True)
1378       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1379     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1380   }
1381   case ISD::SETCC_INVALID:
1382     llvm_unreachable("Invalid setcc condcode!");
1383   }
1384   return SDValue();
1385 }
1386 
1387 std::pair<SDValue, SDValue>
1388 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1389   SDLoc SL(Op);
1390 
1391   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1392 
1393   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1394   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1395 
1396   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1397   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1398 
1399   return std::make_pair(Lo, Hi);
1400 }
1401 
1402 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1403   SDLoc SL(Op);
1404 
1405   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1406   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1407   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1408 }
1409 
1410 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1411   SDLoc SL(Op);
1412 
1413   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1414   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1415   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1416 }
1417 
1418 // Split a vector type into two parts. The first part is a power of two vector.
1419 // The second part is whatever is left over, and is a scalar if it would
1420 // otherwise be a 1-vector.
1421 std::pair<EVT, EVT>
1422 AMDGPUTargetLowering::getSplitDestVTs(const EVT &VT, SelectionDAG &DAG) const {
1423   EVT LoVT, HiVT;
1424   EVT EltVT = VT.getVectorElementType();
1425   unsigned NumElts = VT.getVectorNumElements();
1426   unsigned LoNumElts = PowerOf2Ceil((NumElts + 1) / 2);
1427   LoVT = EVT::getVectorVT(*DAG.getContext(), EltVT, LoNumElts);
1428   HiVT = NumElts - LoNumElts == 1
1429              ? EltVT
1430              : EVT::getVectorVT(*DAG.getContext(), EltVT, NumElts - LoNumElts);
1431   return std::make_pair(LoVT, HiVT);
1432 }
1433 
1434 // Split a vector value into two parts of types LoVT and HiVT. HiVT could be
1435 // scalar.
1436 std::pair<SDValue, SDValue>
1437 AMDGPUTargetLowering::splitVector(const SDValue &N, const SDLoc &DL,
1438                                   const EVT &LoVT, const EVT &HiVT,
1439                                   SelectionDAG &DAG) const {
1440   assert(LoVT.getVectorNumElements() +
1441                  (HiVT.isVector() ? HiVT.getVectorNumElements() : 1) <=
1442              N.getValueType().getVectorNumElements() &&
1443          "More vector elements requested than available!");
1444   SDValue Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, LoVT, N,
1445                            DAG.getVectorIdxConstant(0, DL));
1446   SDValue Hi = DAG.getNode(
1447       HiVT.isVector() ? ISD::EXTRACT_SUBVECTOR : ISD::EXTRACT_VECTOR_ELT, DL,
1448       HiVT, N, DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), DL));
1449   return std::make_pair(Lo, Hi);
1450 }
1451 
1452 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1453                                               SelectionDAG &DAG) const {
1454   LoadSDNode *Load = cast<LoadSDNode>(Op);
1455   EVT VT = Op.getValueType();
1456   SDLoc SL(Op);
1457 
1458 
1459   // If this is a 2 element vector, we really want to scalarize and not create
1460   // weird 1 element vectors.
1461   if (VT.getVectorNumElements() == 2) {
1462     SDValue Ops[2];
1463     std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(Load, DAG);
1464     return DAG.getMergeValues(Ops, SL);
1465   }
1466 
1467   SDValue BasePtr = Load->getBasePtr();
1468   EVT MemVT = Load->getMemoryVT();
1469 
1470   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1471 
1472   EVT LoVT, HiVT;
1473   EVT LoMemVT, HiMemVT;
1474   SDValue Lo, Hi;
1475 
1476   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1477   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1478   std::tie(Lo, Hi) = splitVector(Op, SL, LoVT, HiVT, DAG);
1479 
1480   unsigned Size = LoMemVT.getStoreSize();
1481   unsigned BaseAlign = Load->getAlignment();
1482   unsigned HiAlign = MinAlign(BaseAlign, Size);
1483 
1484   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1485                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1486                                   BaseAlign, Load->getMemOperand()->getFlags());
1487   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1488   SDValue HiLoad =
1489       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1490                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1491                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1492 
1493   SDValue Join;
1494   if (LoVT == HiVT) {
1495     // This is the case that the vector is power of two so was evenly split.
1496     Join = DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad);
1497   } else {
1498     Join = DAG.getNode(ISD::INSERT_SUBVECTOR, SL, VT, DAG.getUNDEF(VT), LoLoad,
1499                        DAG.getVectorIdxConstant(0, SL));
1500     Join = DAG.getNode(
1501         HiVT.isVector() ? ISD::INSERT_SUBVECTOR : ISD::INSERT_VECTOR_ELT, SL,
1502         VT, Join, HiLoad,
1503         DAG.getVectorIdxConstant(LoVT.getVectorNumElements(), SL));
1504   }
1505 
1506   SDValue Ops[] = {Join, DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1507                                      LoLoad.getValue(1), HiLoad.getValue(1))};
1508 
1509   return DAG.getMergeValues(Ops, SL);
1510 }
1511 
1512 // Widen a vector load from vec3 to vec4.
1513 SDValue AMDGPUTargetLowering::WidenVectorLoad(SDValue Op,
1514                                               SelectionDAG &DAG) const {
1515   LoadSDNode *Load = cast<LoadSDNode>(Op);
1516   EVT VT = Op.getValueType();
1517   assert(VT.getVectorNumElements() == 3);
1518   SDValue BasePtr = Load->getBasePtr();
1519   EVT MemVT = Load->getMemoryVT();
1520   SDLoc SL(Op);
1521   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1522   unsigned BaseAlign = Load->getAlignment();
1523 
1524   EVT WideVT =
1525       EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(), 4);
1526   EVT WideMemVT =
1527       EVT::getVectorVT(*DAG.getContext(), MemVT.getVectorElementType(), 4);
1528   SDValue WideLoad = DAG.getExtLoad(
1529       Load->getExtensionType(), SL, WideVT, Load->getChain(), BasePtr, SrcValue,
1530       WideMemVT, BaseAlign, Load->getMemOperand()->getFlags());
1531   return DAG.getMergeValues(
1532       {DAG.getNode(ISD::EXTRACT_SUBVECTOR, SL, VT, WideLoad,
1533                    DAG.getVectorIdxConstant(0, SL)),
1534        WideLoad.getValue(1)},
1535       SL);
1536 }
1537 
1538 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1539                                                SelectionDAG &DAG) const {
1540   StoreSDNode *Store = cast<StoreSDNode>(Op);
1541   SDValue Val = Store->getValue();
1542   EVT VT = Val.getValueType();
1543 
1544   // If this is a 2 element vector, we really want to scalarize and not create
1545   // weird 1 element vectors.
1546   if (VT.getVectorNumElements() == 2)
1547     return scalarizeVectorStore(Store, DAG);
1548 
1549   EVT MemVT = Store->getMemoryVT();
1550   SDValue Chain = Store->getChain();
1551   SDValue BasePtr = Store->getBasePtr();
1552   SDLoc SL(Op);
1553 
1554   EVT LoVT, HiVT;
1555   EVT LoMemVT, HiMemVT;
1556   SDValue Lo, Hi;
1557 
1558   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1559   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1560   std::tie(Lo, Hi) = splitVector(Val, SL, LoVT, HiVT, DAG);
1561 
1562   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1563 
1564   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1565   unsigned BaseAlign = Store->getAlignment();
1566   unsigned Size = LoMemVT.getStoreSize();
1567   unsigned HiAlign = MinAlign(BaseAlign, Size);
1568 
1569   SDValue LoStore =
1570       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1571                         Store->getMemOperand()->getFlags());
1572   SDValue HiStore =
1573       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1574                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1575 
1576   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1577 }
1578 
1579 // This is a shortcut for integer division because we have fast i32<->f32
1580 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1581 // float is enough to accurately represent up to a 24-bit signed integer.
1582 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1583                                             bool Sign) const {
1584   SDLoc DL(Op);
1585   EVT VT = Op.getValueType();
1586   SDValue LHS = Op.getOperand(0);
1587   SDValue RHS = Op.getOperand(1);
1588   MVT IntVT = MVT::i32;
1589   MVT FltVT = MVT::f32;
1590 
1591   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1592   if (LHSSignBits < 9)
1593     return SDValue();
1594 
1595   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1596   if (RHSSignBits < 9)
1597     return SDValue();
1598 
1599   unsigned BitSize = VT.getSizeInBits();
1600   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1601   unsigned DivBits = BitSize - SignBits;
1602   if (Sign)
1603     ++DivBits;
1604 
1605   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1606   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1607 
1608   SDValue jq = DAG.getConstant(1, DL, IntVT);
1609 
1610   if (Sign) {
1611     // char|short jq = ia ^ ib;
1612     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1613 
1614     // jq = jq >> (bitsize - 2)
1615     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1616                      DAG.getConstant(BitSize - 2, DL, VT));
1617 
1618     // jq = jq | 0x1
1619     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1620   }
1621 
1622   // int ia = (int)LHS;
1623   SDValue ia = LHS;
1624 
1625   // int ib, (int)RHS;
1626   SDValue ib = RHS;
1627 
1628   // float fa = (float)ia;
1629   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1630 
1631   // float fb = (float)ib;
1632   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1633 
1634   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1635                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1636 
1637   // fq = trunc(fq);
1638   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1639 
1640   // float fqneg = -fq;
1641   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1642 
1643   MachineFunction &MF = DAG.getMachineFunction();
1644   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
1645 
1646   // float fr = mad(fqneg, fb, fa);
1647   unsigned OpCode = !MFI->getMode().allFP32Denormals() ?
1648                     (unsigned)ISD::FMAD :
1649                     (unsigned)AMDGPUISD::FMAD_FTZ;
1650 
1651   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1652 
1653   // int iq = (int)fq;
1654   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1655 
1656   // fr = fabs(fr);
1657   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1658 
1659   // fb = fabs(fb);
1660   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1661 
1662   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1663 
1664   // int cv = fr >= fb;
1665   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1666 
1667   // jq = (cv ? jq : 0);
1668   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1669 
1670   // dst = iq + jq;
1671   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1672 
1673   // Rem needs compensation, it's easier to recompute it
1674   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1675   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1676 
1677   // Truncate to number of bits this divide really is.
1678   if (Sign) {
1679     SDValue InRegSize
1680       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1681     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1682     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1683   } else {
1684     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1685     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1686     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1687   }
1688 
1689   return DAG.getMergeValues({ Div, Rem }, DL);
1690 }
1691 
1692 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1693                                       SelectionDAG &DAG,
1694                                       SmallVectorImpl<SDValue> &Results) const {
1695   SDLoc DL(Op);
1696   EVT VT = Op.getValueType();
1697 
1698   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1699 
1700   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1701 
1702   SDValue One = DAG.getConstant(1, DL, HalfVT);
1703   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1704 
1705   //HiLo split
1706   SDValue LHS = Op.getOperand(0);
1707   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1708   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1709 
1710   SDValue RHS = Op.getOperand(1);
1711   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1712   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1713 
1714   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1715       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1716 
1717     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1718                               LHS_Lo, RHS_Lo);
1719 
1720     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1721     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1722 
1723     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1724     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1725     return;
1726   }
1727 
1728   if (isTypeLegal(MVT::i64)) {
1729     MachineFunction &MF = DAG.getMachineFunction();
1730     const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1731 
1732     // Compute denominator reciprocal.
1733     unsigned FMAD = !MFI->getMode().allFP32Denormals() ?
1734                     (unsigned)ISD::FMAD :
1735                     (unsigned)AMDGPUISD::FMAD_FTZ;
1736 
1737 
1738     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1739     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1740     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1741       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1742       Cvt_Lo);
1743     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1744     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1745       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1746     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1747       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1748     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1749     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1750       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1751       Mul1);
1752     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1753     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1754     SDValue Rcp64 = DAG.getBitcast(VT,
1755                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1756 
1757     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1758     SDValue One64  = DAG.getConstant(1, DL, VT);
1759     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1760     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1761 
1762     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1763     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1764     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1765     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1766                                     Zero);
1767     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1768                                     One);
1769 
1770     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1771                                   Mulhi1_Lo, Zero1);
1772     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1773                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1774     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1775     SDValue Add1 = DAG.getBitcast(VT,
1776                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1777 
1778     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1779     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1780     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1781                                     Zero);
1782     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1783                                     One);
1784 
1785     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1786                                   Mulhi2_Lo, Zero1);
1787     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1788                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1789     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1790                                   Zero, Add2_Lo.getValue(1));
1791     SDValue Add2 = DAG.getBitcast(VT,
1792                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1793     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1794 
1795     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1796 
1797     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1798     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1799     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1800                                   Mul3_Lo, Zero1);
1801     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1802                                   Mul3_Hi, Sub1_Lo.getValue(1));
1803     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1804     SDValue Sub1 = DAG.getBitcast(VT,
1805                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1806 
1807     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1808     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1809                                  ISD::SETUGE);
1810     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1811                                  ISD::SETUGE);
1812     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1813 
1814     // TODO: Here and below portions of the code can be enclosed into if/endif.
1815     // Currently control flow is unconditional and we have 4 selects after
1816     // potential endif to substitute PHIs.
1817 
1818     // if C3 != 0 ...
1819     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1820                                   RHS_Lo, Zero1);
1821     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1822                                   RHS_Hi, Sub1_Lo.getValue(1));
1823     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1824                                   Zero, Sub2_Lo.getValue(1));
1825     SDValue Sub2 = DAG.getBitcast(VT,
1826                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1827 
1828     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1829 
1830     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1831                                  ISD::SETUGE);
1832     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1833                                  ISD::SETUGE);
1834     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1835 
1836     // if (C6 != 0)
1837     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1838 
1839     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1840                                   RHS_Lo, Zero1);
1841     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1842                                   RHS_Hi, Sub2_Lo.getValue(1));
1843     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1844                                   Zero, Sub3_Lo.getValue(1));
1845     SDValue Sub3 = DAG.getBitcast(VT,
1846                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1847 
1848     // endif C6
1849     // endif C3
1850 
1851     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1852     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1853 
1854     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1855     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1856 
1857     Results.push_back(Div);
1858     Results.push_back(Rem);
1859 
1860     return;
1861   }
1862 
1863   // r600 expandion.
1864   // Get Speculative values
1865   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1866   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1867 
1868   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1869   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1870   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1871 
1872   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1873   SDValue DIV_Lo = Zero;
1874 
1875   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1876 
1877   for (unsigned i = 0; i < halfBitWidth; ++i) {
1878     const unsigned bitPos = halfBitWidth - i - 1;
1879     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1880     // Get value of high bit
1881     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1882     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1883     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1884 
1885     // Shift
1886     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1887     // Add LHS high bit
1888     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1889 
1890     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1891     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1892 
1893     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1894 
1895     // Update REM
1896     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1897     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1898   }
1899 
1900   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1901   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1902   Results.push_back(DIV);
1903   Results.push_back(REM);
1904 }
1905 
1906 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1907                                            SelectionDAG &DAG) const {
1908   SDLoc DL(Op);
1909   EVT VT = Op.getValueType();
1910 
1911   if (VT == MVT::i64) {
1912     SmallVector<SDValue, 2> Results;
1913     LowerUDIVREM64(Op, DAG, Results);
1914     return DAG.getMergeValues(Results, DL);
1915   }
1916 
1917   if (VT == MVT::i32) {
1918     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1919       return Res;
1920   }
1921 
1922   SDValue Num = Op.getOperand(0);
1923   SDValue Den = Op.getOperand(1);
1924 
1925   // RCP =  URECIP(Den) = 2^32 / Den + e
1926   // e is rounding error.
1927   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1928 
1929   // RCP_LO = mul(RCP, Den) */
1930   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1931 
1932   // RCP_HI = mulhu (RCP, Den) */
1933   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1934 
1935   // NEG_RCP_LO = -RCP_LO
1936   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1937                                                      RCP_LO);
1938 
1939   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1940   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1941                                            NEG_RCP_LO, RCP_LO,
1942                                            ISD::SETEQ);
1943   // Calculate the rounding error from the URECIP instruction
1944   // E = mulhu(ABS_RCP_LO, RCP)
1945   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1946 
1947   // RCP_A_E = RCP + E
1948   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1949 
1950   // RCP_S_E = RCP - E
1951   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1952 
1953   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1954   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1955                                      RCP_A_E, RCP_S_E,
1956                                      ISD::SETEQ);
1957   // Quotient = mulhu(Tmp0, Num)
1958   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1959 
1960   // Num_S_Remainder = Quotient * Den
1961   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1962 
1963   // Remainder = Num - Num_S_Remainder
1964   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1965 
1966   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1967   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1968                                                  DAG.getConstant(-1, DL, VT),
1969                                                  DAG.getConstant(0, DL, VT),
1970                                                  ISD::SETUGE);
1971   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1972   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1973                                                   Num_S_Remainder,
1974                                                   DAG.getConstant(-1, DL, VT),
1975                                                   DAG.getConstant(0, DL, VT),
1976                                                   ISD::SETUGE);
1977   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1978   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1979                                                Remainder_GE_Zero);
1980 
1981   // Calculate Division result:
1982 
1983   // Quotient_A_One = Quotient + 1
1984   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1985                                        DAG.getConstant(1, DL, VT));
1986 
1987   // Quotient_S_One = Quotient - 1
1988   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1989                                        DAG.getConstant(1, DL, VT));
1990 
1991   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1992   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1993                                      Quotient, Quotient_A_One, ISD::SETEQ);
1994 
1995   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1996   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1997                             Quotient_S_One, Div, ISD::SETEQ);
1998 
1999   // Calculate Rem result:
2000 
2001   // Remainder_S_Den = Remainder - Den
2002   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
2003 
2004   // Remainder_A_Den = Remainder + Den
2005   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
2006 
2007   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
2008   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
2009                                     Remainder, Remainder_S_Den, ISD::SETEQ);
2010 
2011   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
2012   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
2013                             Remainder_A_Den, Rem, ISD::SETEQ);
2014   SDValue Ops[2] = {
2015     Div,
2016     Rem
2017   };
2018   return DAG.getMergeValues(Ops, DL);
2019 }
2020 
2021 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
2022                                            SelectionDAG &DAG) const {
2023   SDLoc DL(Op);
2024   EVT VT = Op.getValueType();
2025 
2026   SDValue LHS = Op.getOperand(0);
2027   SDValue RHS = Op.getOperand(1);
2028 
2029   SDValue Zero = DAG.getConstant(0, DL, VT);
2030   SDValue NegOne = DAG.getConstant(-1, DL, VT);
2031 
2032   if (VT == MVT::i32) {
2033     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
2034       return Res;
2035   }
2036 
2037   if (VT == MVT::i64 &&
2038       DAG.ComputeNumSignBits(LHS) > 32 &&
2039       DAG.ComputeNumSignBits(RHS) > 32) {
2040     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
2041 
2042     //HiLo split
2043     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
2044     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
2045     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
2046                                  LHS_Lo, RHS_Lo);
2047     SDValue Res[2] = {
2048       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
2049       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
2050     };
2051     return DAG.getMergeValues(Res, DL);
2052   }
2053 
2054   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
2055   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
2056   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
2057   SDValue RSign = LHSign; // Remainder sign is the same as LHS
2058 
2059   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
2060   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
2061 
2062   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
2063   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
2064 
2065   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
2066   SDValue Rem = Div.getValue(1);
2067 
2068   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
2069   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
2070 
2071   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
2072   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
2073 
2074   SDValue Res[2] = {
2075     Div,
2076     Rem
2077   };
2078   return DAG.getMergeValues(Res, DL);
2079 }
2080 
2081 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2082 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2083   SDLoc SL(Op);
2084   EVT VT = Op.getValueType();
2085   SDValue X = Op.getOperand(0);
2086   SDValue Y = Op.getOperand(1);
2087 
2088   // TODO: Should this propagate fast-math-flags?
2089 
2090   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2091   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2092   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2093 
2094   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2095 }
2096 
2097 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2098   SDLoc SL(Op);
2099   SDValue Src = Op.getOperand(0);
2100 
2101   // result = trunc(src)
2102   // if (src > 0.0 && src != result)
2103   //   result += 1.0
2104 
2105   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2106 
2107   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2108   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2109 
2110   EVT SetCCVT =
2111       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2112 
2113   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2114   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2115   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2116 
2117   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2118   // TODO: Should this propagate fast-math-flags?
2119   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2120 }
2121 
2122 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2123                                   SelectionDAG &DAG) {
2124   const unsigned FractBits = 52;
2125   const unsigned ExpBits = 11;
2126 
2127   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2128                                 Hi,
2129                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2130                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2131   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2132                             DAG.getConstant(1023, SL, MVT::i32));
2133 
2134   return Exp;
2135 }
2136 
2137 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2138   SDLoc SL(Op);
2139   SDValue Src = Op.getOperand(0);
2140 
2141   assert(Op.getValueType() == MVT::f64);
2142 
2143   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2144   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2145 
2146   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2147 
2148   // Extract the upper half, since this is where we will find the sign and
2149   // exponent.
2150   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2151 
2152   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2153 
2154   const unsigned FractBits = 52;
2155 
2156   // Extract the sign bit.
2157   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2158   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2159 
2160   // Extend back to 64-bits.
2161   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2162   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2163 
2164   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2165   const SDValue FractMask
2166     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2167 
2168   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2169   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2170   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2171 
2172   EVT SetCCVT =
2173       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2174 
2175   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2176 
2177   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2178   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2179 
2180   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2181   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2182 
2183   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2184 }
2185 
2186 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2187   SDLoc SL(Op);
2188   SDValue Src = Op.getOperand(0);
2189 
2190   assert(Op.getValueType() == MVT::f64);
2191 
2192   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2193   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2194   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2195 
2196   // TODO: Should this propagate fast-math-flags?
2197 
2198   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2199   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2200 
2201   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2202 
2203   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2204   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2205 
2206   EVT SetCCVT =
2207       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2208   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2209 
2210   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2211 }
2212 
2213 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2214   // FNEARBYINT and FRINT are the same, except in their handling of FP
2215   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2216   // rint, so just treat them as equivalent.
2217   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2218 }
2219 
2220 // XXX - May require not supporting f32 denormals?
2221 
2222 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2223 // compare and vselect end up producing worse code than scalarizing the whole
2224 // operation.
2225 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2226   SDLoc SL(Op);
2227   SDValue X = Op.getOperand(0);
2228   EVT VT = Op.getValueType();
2229 
2230   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2231 
2232   // TODO: Should this propagate fast-math-flags?
2233 
2234   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2235 
2236   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2237 
2238   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2239   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2240   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2241 
2242   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2243 
2244   EVT SetCCVT =
2245       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2246 
2247   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2248 
2249   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2250 
2251   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2252 }
2253 
2254 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2255   SDLoc SL(Op);
2256   SDValue Src = Op.getOperand(0);
2257 
2258   // result = trunc(src);
2259   // if (src < 0.0 && src != result)
2260   //   result += -1.0.
2261 
2262   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2263 
2264   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2265   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2266 
2267   EVT SetCCVT =
2268       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2269 
2270   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2271   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2272   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2273 
2274   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2275   // TODO: Should this propagate fast-math-flags?
2276   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2277 }
2278 
2279 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2280                                         double Log2BaseInverted) const {
2281   EVT VT = Op.getValueType();
2282 
2283   SDLoc SL(Op);
2284   SDValue Operand = Op.getOperand(0);
2285   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2286   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2287 
2288   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2289 }
2290 
2291 // exp2(M_LOG2E_F * f);
2292 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2293   EVT VT = Op.getValueType();
2294   SDLoc SL(Op);
2295   SDValue Src = Op.getOperand(0);
2296 
2297   const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
2298   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2299   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2300 }
2301 
2302 static bool isCtlzOpc(unsigned Opc) {
2303   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2304 }
2305 
2306 static bool isCttzOpc(unsigned Opc) {
2307   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2308 }
2309 
2310 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2311   SDLoc SL(Op);
2312   SDValue Src = Op.getOperand(0);
2313   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2314                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2315 
2316   unsigned ISDOpc, NewOpc;
2317   if (isCtlzOpc(Op.getOpcode())) {
2318     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2319     NewOpc = AMDGPUISD::FFBH_U32;
2320   } else if (isCttzOpc(Op.getOpcode())) {
2321     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2322     NewOpc = AMDGPUISD::FFBL_B32;
2323   } else
2324     llvm_unreachable("Unexpected OPCode!!!");
2325 
2326 
2327   if (ZeroUndef && Src.getValueType() == MVT::i32)
2328     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2329 
2330   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2331 
2332   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2333   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2334 
2335   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2336   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2337 
2338   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2339                                    *DAG.getContext(), MVT::i32);
2340 
2341   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2342   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2343 
2344   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2345   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2346 
2347   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2348   SDValue Add, NewOpr;
2349   if (isCtlzOpc(Op.getOpcode())) {
2350     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2351     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2352     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2353   } else {
2354     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2355     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2356     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2357   }
2358 
2359   if (!ZeroUndef) {
2360     // Test if the full 64-bit input is zero.
2361 
2362     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2363     // which we probably don't want.
2364     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2365     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2366     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2367 
2368     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2369     // with the same cycles, otherwise it is slower.
2370     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2371     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2372 
2373     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2374 
2375     // The instruction returns -1 for 0 input, but the defined intrinsic
2376     // behavior is to return the number of bits.
2377     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2378                          SrcIsZero, Bits32, NewOpr);
2379   }
2380 
2381   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2382 }
2383 
2384 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2385                                                bool Signed) const {
2386   // Unsigned
2387   // cul2f(ulong u)
2388   //{
2389   //  uint lz = clz(u);
2390   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2391   //  u = (u << lz) & 0x7fffffffffffffffUL;
2392   //  ulong t = u & 0xffffffffffUL;
2393   //  uint v = (e << 23) | (uint)(u >> 40);
2394   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2395   //  return as_float(v + r);
2396   //}
2397   // Signed
2398   // cl2f(long l)
2399   //{
2400   //  long s = l >> 63;
2401   //  float r = cul2f((l + s) ^ s);
2402   //  return s ? -r : r;
2403   //}
2404 
2405   SDLoc SL(Op);
2406   SDValue Src = Op.getOperand(0);
2407   SDValue L = Src;
2408 
2409   SDValue S;
2410   if (Signed) {
2411     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2412     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2413 
2414     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2415     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2416   }
2417 
2418   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2419                                    *DAG.getContext(), MVT::f32);
2420 
2421 
2422   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2423   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2424   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2425   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2426 
2427   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2428   SDValue E = DAG.getSelect(SL, MVT::i32,
2429     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2430     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2431     ZeroI32);
2432 
2433   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2434     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2435     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2436 
2437   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2438                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2439 
2440   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2441                              U, DAG.getConstant(40, SL, MVT::i64));
2442 
2443   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2444     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2445     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2446 
2447   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2448   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2449   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2450 
2451   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2452 
2453   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2454 
2455   SDValue R = DAG.getSelect(SL, MVT::i32,
2456     RCmp,
2457     One,
2458     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2459   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2460   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2461 
2462   if (!Signed)
2463     return R;
2464 
2465   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2466   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2467 }
2468 
2469 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2470                                                bool Signed) const {
2471   SDLoc SL(Op);
2472   SDValue Src = Op.getOperand(0);
2473 
2474   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2475 
2476   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2477                            DAG.getConstant(0, SL, MVT::i32));
2478   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2479                            DAG.getConstant(1, SL, MVT::i32));
2480 
2481   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2482                               SL, MVT::f64, Hi);
2483 
2484   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2485 
2486   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2487                               DAG.getConstant(32, SL, MVT::i32));
2488   // TODO: Should this propagate fast-math-flags?
2489   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2490 }
2491 
2492 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2493                                                SelectionDAG &DAG) const {
2494   // TODO: Factor out code common with LowerSINT_TO_FP.
2495   EVT DestVT = Op.getValueType();
2496   SDValue Src = Op.getOperand(0);
2497   EVT SrcVT = Src.getValueType();
2498 
2499   if (SrcVT == MVT::i16) {
2500     if (DestVT == MVT::f16)
2501       return Op;
2502     SDLoc DL(Op);
2503 
2504     // Promote src to i32
2505     SDValue Ext = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Src);
2506     return DAG.getNode(ISD::UINT_TO_FP, DL, DestVT, Ext);
2507   }
2508 
2509   assert(SrcVT == MVT::i64 && "operation should be legal");
2510 
2511   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2512     SDLoc DL(Op);
2513 
2514     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2515     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2516     SDValue FPRound =
2517         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2518 
2519     return FPRound;
2520   }
2521 
2522   if (DestVT == MVT::f32)
2523     return LowerINT_TO_FP32(Op, DAG, false);
2524 
2525   assert(DestVT == MVT::f64);
2526   return LowerINT_TO_FP64(Op, DAG, false);
2527 }
2528 
2529 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2530                                               SelectionDAG &DAG) const {
2531   EVT DestVT = Op.getValueType();
2532 
2533   SDValue Src = Op.getOperand(0);
2534   EVT SrcVT = Src.getValueType();
2535 
2536   if (SrcVT == MVT::i16) {
2537     if (DestVT == MVT::f16)
2538       return Op;
2539 
2540     SDLoc DL(Op);
2541     // Promote src to i32
2542     SDValue Ext = DAG.getNode(ISD::SIGN_EXTEND, DL, MVT::i32, Src);
2543     return DAG.getNode(ISD::SINT_TO_FP, DL, DestVT, Ext);
2544   }
2545 
2546   assert(SrcVT == MVT::i64 && "operation should be legal");
2547 
2548   // TODO: Factor out code common with LowerUINT_TO_FP.
2549 
2550   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2551     SDLoc DL(Op);
2552     SDValue Src = Op.getOperand(0);
2553 
2554     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2555     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2556     SDValue FPRound =
2557         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2558 
2559     return FPRound;
2560   }
2561 
2562   if (DestVT == MVT::f32)
2563     return LowerINT_TO_FP32(Op, DAG, true);
2564 
2565   assert(DestVT == MVT::f64);
2566   return LowerINT_TO_FP64(Op, DAG, true);
2567 }
2568 
2569 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2570                                                bool Signed) const {
2571   SDLoc SL(Op);
2572 
2573   SDValue Src = Op.getOperand(0);
2574 
2575   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2576 
2577   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2578                                  MVT::f64);
2579   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2580                                  MVT::f64);
2581   // TODO: Should this propagate fast-math-flags?
2582   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2583 
2584   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2585 
2586 
2587   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2588 
2589   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2590                            MVT::i32, FloorMul);
2591   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2592 
2593   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2594 
2595   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2596 }
2597 
2598 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2599   SDLoc DL(Op);
2600   SDValue N0 = Op.getOperand(0);
2601 
2602   // Convert to target node to get known bits
2603   if (N0.getValueType() == MVT::f32)
2604     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2605 
2606   if (getTargetMachine().Options.UnsafeFPMath) {
2607     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2608     return SDValue();
2609   }
2610 
2611   assert(N0.getSimpleValueType() == MVT::f64);
2612 
2613   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2614   const unsigned ExpMask = 0x7ff;
2615   const unsigned ExpBiasf64 = 1023;
2616   const unsigned ExpBiasf16 = 15;
2617   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2618   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2619   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2620   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2621                            DAG.getConstant(32, DL, MVT::i64));
2622   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2623   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2624   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2625                           DAG.getConstant(20, DL, MVT::i64));
2626   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2627                   DAG.getConstant(ExpMask, DL, MVT::i32));
2628   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2629   // add the f16 bias (15) to get the biased exponent for the f16 format.
2630   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2631                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2632 
2633   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2634                           DAG.getConstant(8, DL, MVT::i32));
2635   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2636                   DAG.getConstant(0xffe, DL, MVT::i32));
2637 
2638   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2639                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2640   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2641 
2642   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2643   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2644 
2645   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2646   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2647       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2648                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2649 
2650   // N = M | (E << 12);
2651   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2652       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2653                   DAG.getConstant(12, DL, MVT::i32)));
2654 
2655   // B = clamp(1-E, 0, 13);
2656   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2657                                   One, E);
2658   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2659   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2660                   DAG.getConstant(13, DL, MVT::i32));
2661 
2662   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2663                                    DAG.getConstant(0x1000, DL, MVT::i32));
2664 
2665   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2666   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2667   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2668   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2669 
2670   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2671   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2672                               DAG.getConstant(0x7, DL, MVT::i32));
2673   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2674                   DAG.getConstant(2, DL, MVT::i32));
2675   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2676                                One, Zero, ISD::SETEQ);
2677   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2678                                One, Zero, ISD::SETGT);
2679   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2680   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2681 
2682   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2683                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2684   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2685                       I, V, ISD::SETEQ);
2686 
2687   // Extract the sign bit.
2688   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2689                             DAG.getConstant(16, DL, MVT::i32));
2690   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2691                      DAG.getConstant(0x8000, DL, MVT::i32));
2692 
2693   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2694   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2695 }
2696 
2697 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2698                                               SelectionDAG &DAG) const {
2699   SDValue Src = Op.getOperand(0);
2700 
2701   // TODO: Factor out code common with LowerFP_TO_UINT.
2702 
2703   EVT SrcVT = Src.getValueType();
2704   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2705     SDLoc DL(Op);
2706 
2707     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2708     SDValue FpToInt32 =
2709         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2710 
2711     return FpToInt32;
2712   }
2713 
2714   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2715     return LowerFP64_TO_INT(Op, DAG, true);
2716 
2717   return SDValue();
2718 }
2719 
2720 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2721                                               SelectionDAG &DAG) const {
2722   SDValue Src = Op.getOperand(0);
2723 
2724   // TODO: Factor out code common with LowerFP_TO_SINT.
2725 
2726   EVT SrcVT = Src.getValueType();
2727   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2728     SDLoc DL(Op);
2729 
2730     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2731     SDValue FpToInt32 =
2732         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2733 
2734     return FpToInt32;
2735   }
2736 
2737   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2738     return LowerFP64_TO_INT(Op, DAG, false);
2739 
2740   return SDValue();
2741 }
2742 
2743 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2744                                                      SelectionDAG &DAG) const {
2745   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2746   MVT VT = Op.getSimpleValueType();
2747   MVT ScalarVT = VT.getScalarType();
2748 
2749   assert(VT.isVector());
2750 
2751   SDValue Src = Op.getOperand(0);
2752   SDLoc DL(Op);
2753 
2754   // TODO: Don't scalarize on Evergreen?
2755   unsigned NElts = VT.getVectorNumElements();
2756   SmallVector<SDValue, 8> Args;
2757   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2758 
2759   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2760   for (unsigned I = 0; I < NElts; ++I)
2761     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2762 
2763   return DAG.getBuildVector(VT, DL, Args);
2764 }
2765 
2766 //===----------------------------------------------------------------------===//
2767 // Custom DAG optimizations
2768 //===----------------------------------------------------------------------===//
2769 
2770 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2771   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2772 }
2773 
2774 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2775   EVT VT = Op.getValueType();
2776   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2777                                      // as unsigned 24-bit values.
2778     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2779 }
2780 
2781 static SDValue simplifyI24(SDNode *Node24,
2782                            TargetLowering::DAGCombinerInfo &DCI) {
2783   SelectionDAG &DAG = DCI.DAG;
2784   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2785   bool IsIntrin = Node24->getOpcode() == ISD::INTRINSIC_WO_CHAIN;
2786 
2787   SDValue LHS = IsIntrin ? Node24->getOperand(1) : Node24->getOperand(0);
2788   SDValue RHS = IsIntrin ? Node24->getOperand(2) : Node24->getOperand(1);
2789   unsigned NewOpcode = Node24->getOpcode();
2790   if (IsIntrin) {
2791     unsigned IID = cast<ConstantSDNode>(Node24->getOperand(0))->getZExtValue();
2792     NewOpcode = IID == Intrinsic::amdgcn_mul_i24 ?
2793       AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
2794   }
2795 
2796   APInt Demanded = APInt::getLowBitsSet(LHS.getValueSizeInBits(), 24);
2797 
2798   // First try to simplify using SimplifyMultipleUseDemandedBits which allows
2799   // the operands to have other uses, but will only perform simplifications that
2800   // involve bypassing some nodes for this user.
2801   SDValue DemandedLHS = TLI.SimplifyMultipleUseDemandedBits(LHS, Demanded, DAG);
2802   SDValue DemandedRHS = TLI.SimplifyMultipleUseDemandedBits(RHS, Demanded, DAG);
2803   if (DemandedLHS || DemandedRHS)
2804     return DAG.getNode(NewOpcode, SDLoc(Node24), Node24->getVTList(),
2805                        DemandedLHS ? DemandedLHS : LHS,
2806                        DemandedRHS ? DemandedRHS : RHS);
2807 
2808   // Now try SimplifyDemandedBits which can simplify the nodes used by our
2809   // operands if this node is the only user.
2810   if (TLI.SimplifyDemandedBits(LHS, Demanded, DCI))
2811     return SDValue(Node24, 0);
2812   if (TLI.SimplifyDemandedBits(RHS, Demanded, DCI))
2813     return SDValue(Node24, 0);
2814 
2815   return SDValue();
2816 }
2817 
2818 template <typename IntTy>
2819 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2820                                uint32_t Width, const SDLoc &DL) {
2821   if (Width + Offset < 32) {
2822     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2823     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2824     return DAG.getConstant(Result, DL, MVT::i32);
2825   }
2826 
2827   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2828 }
2829 
2830 static bool hasVolatileUser(SDNode *Val) {
2831   for (SDNode *U : Val->uses()) {
2832     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2833       if (M->isVolatile())
2834         return true;
2835     }
2836   }
2837 
2838   return false;
2839 }
2840 
2841 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2842   // i32 vectors are the canonical memory type.
2843   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2844     return false;
2845 
2846   if (!VT.isByteSized())
2847     return false;
2848 
2849   unsigned Size = VT.getStoreSize();
2850 
2851   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2852     return false;
2853 
2854   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2855     return false;
2856 
2857   return true;
2858 }
2859 
2860 // Replace load of an illegal type with a store of a bitcast to a friendlier
2861 // type.
2862 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2863                                                  DAGCombinerInfo &DCI) const {
2864   if (!DCI.isBeforeLegalize())
2865     return SDValue();
2866 
2867   LoadSDNode *LN = cast<LoadSDNode>(N);
2868   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2869     return SDValue();
2870 
2871   SDLoc SL(N);
2872   SelectionDAG &DAG = DCI.DAG;
2873   EVT VT = LN->getMemoryVT();
2874 
2875   unsigned Size = VT.getStoreSize();
2876   unsigned Align = LN->getAlignment();
2877   if (Align < Size && isTypeLegal(VT)) {
2878     bool IsFast;
2879     unsigned AS = LN->getAddressSpace();
2880 
2881     // Expand unaligned loads earlier than legalization. Due to visitation order
2882     // problems during legalization, the emitted instructions to pack and unpack
2883     // the bytes again are not eliminated in the case of an unaligned copy.
2884     if (!allowsMisalignedMemoryAccesses(
2885             VT, AS, Align, LN->getMemOperand()->getFlags(), &IsFast)) {
2886       SDValue Ops[2];
2887 
2888       if (VT.isVector())
2889         std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(LN, DAG);
2890       else
2891         std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2892 
2893       return DAG.getMergeValues(Ops, SDLoc(N));
2894     }
2895 
2896     if (!IsFast)
2897       return SDValue();
2898   }
2899 
2900   if (!shouldCombineMemoryType(VT))
2901     return SDValue();
2902 
2903   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2904 
2905   SDValue NewLoad
2906     = DAG.getLoad(NewVT, SL, LN->getChain(),
2907                   LN->getBasePtr(), LN->getMemOperand());
2908 
2909   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2910   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2911   return SDValue(N, 0);
2912 }
2913 
2914 // Replace store of an illegal type with a store of a bitcast to a friendlier
2915 // type.
2916 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2917                                                   DAGCombinerInfo &DCI) const {
2918   if (!DCI.isBeforeLegalize())
2919     return SDValue();
2920 
2921   StoreSDNode *SN = cast<StoreSDNode>(N);
2922   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2923     return SDValue();
2924 
2925   EVT VT = SN->getMemoryVT();
2926   unsigned Size = VT.getStoreSize();
2927 
2928   SDLoc SL(N);
2929   SelectionDAG &DAG = DCI.DAG;
2930   unsigned Align = SN->getAlignment();
2931   if (Align < Size && isTypeLegal(VT)) {
2932     bool IsFast;
2933     unsigned AS = SN->getAddressSpace();
2934 
2935     // Expand unaligned stores earlier than legalization. Due to visitation
2936     // order problems during legalization, the emitted instructions to pack and
2937     // unpack the bytes again are not eliminated in the case of an unaligned
2938     // copy.
2939     if (!allowsMisalignedMemoryAccesses(
2940             VT, AS, Align, SN->getMemOperand()->getFlags(), &IsFast)) {
2941       if (VT.isVector())
2942         return scalarizeVectorStore(SN, DAG);
2943 
2944       return expandUnalignedStore(SN, DAG);
2945     }
2946 
2947     if (!IsFast)
2948       return SDValue();
2949   }
2950 
2951   if (!shouldCombineMemoryType(VT))
2952     return SDValue();
2953 
2954   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2955   SDValue Val = SN->getValue();
2956 
2957   //DCI.AddToWorklist(Val.getNode());
2958 
2959   bool OtherUses = !Val.hasOneUse();
2960   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2961   if (OtherUses) {
2962     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2963     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2964   }
2965 
2966   return DAG.getStore(SN->getChain(), SL, CastVal,
2967                       SN->getBasePtr(), SN->getMemOperand());
2968 }
2969 
2970 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2971 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2972 // issues.
2973 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2974                                                         DAGCombinerInfo &DCI) const {
2975   SelectionDAG &DAG = DCI.DAG;
2976   SDValue N0 = N->getOperand(0);
2977 
2978   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2979   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2980   if (N0.getOpcode() == ISD::TRUNCATE) {
2981     SDValue N1 = N->getOperand(1);
2982     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2983     SDLoc SL(N);
2984 
2985     SDValue Src = N0.getOperand(0);
2986     EVT SrcVT = Src.getValueType();
2987     if (SrcVT.bitsGE(ExtVT)) {
2988       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2989       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2990     }
2991   }
2992 
2993   return SDValue();
2994 }
2995 
2996 SDValue AMDGPUTargetLowering::performIntrinsicWOChainCombine(
2997   SDNode *N, DAGCombinerInfo &DCI) const {
2998   unsigned IID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
2999   switch (IID) {
3000   case Intrinsic::amdgcn_mul_i24:
3001   case Intrinsic::amdgcn_mul_u24:
3002     return simplifyI24(N, DCI);
3003   default:
3004     return SDValue();
3005   }
3006 }
3007 
3008 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
3009 /// binary operation \p Opc to it with the corresponding constant operands.
3010 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
3011   DAGCombinerInfo &DCI, const SDLoc &SL,
3012   unsigned Opc, SDValue LHS,
3013   uint32_t ValLo, uint32_t ValHi) const {
3014   SelectionDAG &DAG = DCI.DAG;
3015   SDValue Lo, Hi;
3016   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
3017 
3018   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
3019   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
3020 
3021   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
3022   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
3023 
3024   // Re-visit the ands. It's possible we eliminated one of them and it could
3025   // simplify the vector.
3026   DCI.AddToWorklist(Lo.getNode());
3027   DCI.AddToWorklist(Hi.getNode());
3028 
3029   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
3030   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3031 }
3032 
3033 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
3034                                                 DAGCombinerInfo &DCI) const {
3035   EVT VT = N->getValueType(0);
3036 
3037   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3038   if (!RHS)
3039     return SDValue();
3040 
3041   SDValue LHS = N->getOperand(0);
3042   unsigned RHSVal = RHS->getZExtValue();
3043   if (!RHSVal)
3044     return LHS;
3045 
3046   SDLoc SL(N);
3047   SelectionDAG &DAG = DCI.DAG;
3048 
3049   switch (LHS->getOpcode()) {
3050   default:
3051     break;
3052   case ISD::ZERO_EXTEND:
3053   case ISD::SIGN_EXTEND:
3054   case ISD::ANY_EXTEND: {
3055     SDValue X = LHS->getOperand(0);
3056 
3057     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
3058         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
3059       // Prefer build_vector as the canonical form if packed types are legal.
3060       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
3061       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
3062        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
3063       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
3064     }
3065 
3066     // shl (ext x) => zext (shl x), if shift does not overflow int
3067     if (VT != MVT::i64)
3068       break;
3069     KnownBits Known = DAG.computeKnownBits(X);
3070     unsigned LZ = Known.countMinLeadingZeros();
3071     if (LZ < RHSVal)
3072       break;
3073     EVT XVT = X.getValueType();
3074     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
3075     return DAG.getZExtOrTrunc(Shl, SL, VT);
3076   }
3077   }
3078 
3079   if (VT != MVT::i64)
3080     return SDValue();
3081 
3082   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3083 
3084   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3085   // common case, splitting this into a move and a 32-bit shift is faster and
3086   // the same code size.
3087   if (RHSVal < 32)
3088     return SDValue();
3089 
3090   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3091 
3092   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3093   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3094 
3095   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3096 
3097   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3098   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3099 }
3100 
3101 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3102                                                 DAGCombinerInfo &DCI) const {
3103   if (N->getValueType(0) != MVT::i64)
3104     return SDValue();
3105 
3106   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3107   if (!RHS)
3108     return SDValue();
3109 
3110   SelectionDAG &DAG = DCI.DAG;
3111   SDLoc SL(N);
3112   unsigned RHSVal = RHS->getZExtValue();
3113 
3114   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3115   if (RHSVal == 32) {
3116     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3117     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3118                                    DAG.getConstant(31, SL, MVT::i32));
3119 
3120     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3121     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3122   }
3123 
3124   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3125   if (RHSVal == 63) {
3126     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3127     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3128                                    DAG.getConstant(31, SL, MVT::i32));
3129     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3130     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3131   }
3132 
3133   return SDValue();
3134 }
3135 
3136 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3137                                                 DAGCombinerInfo &DCI) const {
3138   auto *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3139   if (!RHS)
3140     return SDValue();
3141 
3142   EVT VT = N->getValueType(0);
3143   SDValue LHS = N->getOperand(0);
3144   unsigned ShiftAmt = RHS->getZExtValue();
3145   SelectionDAG &DAG = DCI.DAG;
3146   SDLoc SL(N);
3147 
3148   // fold (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1)
3149   // this improves the ability to match BFE patterns in isel.
3150   if (LHS.getOpcode() == ISD::AND) {
3151     if (auto *Mask = dyn_cast<ConstantSDNode>(LHS.getOperand(1))) {
3152       if (Mask->getAPIntValue().isShiftedMask() &&
3153           Mask->getAPIntValue().countTrailingZeros() == ShiftAmt) {
3154         return DAG.getNode(
3155             ISD::AND, SL, VT,
3156             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(0), N->getOperand(1)),
3157             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(1), N->getOperand(1)));
3158       }
3159     }
3160   }
3161 
3162   if (VT != MVT::i64)
3163     return SDValue();
3164 
3165   if (ShiftAmt < 32)
3166     return SDValue();
3167 
3168   // srl i64:x, C for C >= 32
3169   // =>
3170   //   build_pair (srl hi_32(x), C - 32), 0
3171   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3172   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3173 
3174   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, LHS);
3175   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecOp, One);
3176 
3177   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3178   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3179 
3180   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3181 
3182   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3183 }
3184 
3185 SDValue AMDGPUTargetLowering::performTruncateCombine(
3186   SDNode *N, DAGCombinerInfo &DCI) const {
3187   SDLoc SL(N);
3188   SelectionDAG &DAG = DCI.DAG;
3189   EVT VT = N->getValueType(0);
3190   SDValue Src = N->getOperand(0);
3191 
3192   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3193   if (Src.getOpcode() == ISD::BITCAST && !VT.isVector()) {
3194     SDValue Vec = Src.getOperand(0);
3195     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3196       SDValue Elt0 = Vec.getOperand(0);
3197       EVT EltVT = Elt0.getValueType();
3198       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3199         if (EltVT.isFloatingPoint()) {
3200           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3201                              EltVT.changeTypeToInteger(), Elt0);
3202         }
3203 
3204         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3205       }
3206     }
3207   }
3208 
3209   // Equivalent of above for accessing the high element of a vector as an
3210   // integer operation.
3211   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3212   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3213     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3214       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3215         SDValue BV = stripBitcast(Src.getOperand(0));
3216         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3217             BV.getValueType().getVectorNumElements() == 2) {
3218           SDValue SrcElt = BV.getOperand(1);
3219           EVT SrcEltVT = SrcElt.getValueType();
3220           if (SrcEltVT.isFloatingPoint()) {
3221             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3222                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3223           }
3224 
3225           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3226         }
3227       }
3228     }
3229   }
3230 
3231   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3232   //
3233   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3234   //     i16 (trunc (srl (i32 (trunc x), K)))
3235   if (VT.getScalarSizeInBits() < 32) {
3236     EVT SrcVT = Src.getValueType();
3237     if (SrcVT.getScalarSizeInBits() > 32 &&
3238         (Src.getOpcode() == ISD::SRL ||
3239          Src.getOpcode() == ISD::SRA ||
3240          Src.getOpcode() == ISD::SHL)) {
3241       SDValue Amt = Src.getOperand(1);
3242       KnownBits Known = DAG.computeKnownBits(Amt);
3243       unsigned Size = VT.getScalarSizeInBits();
3244       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3245           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3246         EVT MidVT = VT.isVector() ?
3247           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3248                            VT.getVectorNumElements()) : MVT::i32;
3249 
3250         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3251         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3252                                     Src.getOperand(0));
3253         DCI.AddToWorklist(Trunc.getNode());
3254 
3255         if (Amt.getValueType() != NewShiftVT) {
3256           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3257           DCI.AddToWorklist(Amt.getNode());
3258         }
3259 
3260         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3261                                           Trunc, Amt);
3262         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3263       }
3264     }
3265   }
3266 
3267   return SDValue();
3268 }
3269 
3270 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3271 // instructions. If we only match on the legalized i64 mul expansion,
3272 // SimplifyDemandedBits will be unable to remove them because there will be
3273 // multiple uses due to the separate mul + mulh[su].
3274 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3275                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3276   if (Size <= 32) {
3277     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3278     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3279   }
3280 
3281   // Because we want to eliminate extension instructions before the
3282   // operation, we need to create a single user here (i.e. not the separate
3283   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3284 
3285   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3286 
3287   SDValue Mul = DAG.getNode(MulOpc, SL,
3288                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3289 
3290   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3291                      Mul.getValue(0), Mul.getValue(1));
3292 }
3293 
3294 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3295                                                 DAGCombinerInfo &DCI) const {
3296   EVT VT = N->getValueType(0);
3297 
3298   unsigned Size = VT.getSizeInBits();
3299   if (VT.isVector() || Size > 64)
3300     return SDValue();
3301 
3302   // There are i16 integer mul/mad.
3303   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3304     return SDValue();
3305 
3306   SelectionDAG &DAG = DCI.DAG;
3307   SDLoc DL(N);
3308 
3309   SDValue N0 = N->getOperand(0);
3310   SDValue N1 = N->getOperand(1);
3311 
3312   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3313   // in the source into any_extends if the result of the mul is truncated. Since
3314   // we can assume the high bits are whatever we want, use the underlying value
3315   // to avoid the unknown high bits from interfering.
3316   if (N0.getOpcode() == ISD::ANY_EXTEND)
3317     N0 = N0.getOperand(0);
3318 
3319   if (N1.getOpcode() == ISD::ANY_EXTEND)
3320     N1 = N1.getOperand(0);
3321 
3322   SDValue Mul;
3323 
3324   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3325     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3326     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3327     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3328   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3329     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3330     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3331     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3332   } else {
3333     return SDValue();
3334   }
3335 
3336   // We need to use sext even for MUL_U24, because MUL_U24 is used
3337   // for signed multiply of 8 and 16-bit types.
3338   return DAG.getSExtOrTrunc(Mul, DL, VT);
3339 }
3340 
3341 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3342                                                   DAGCombinerInfo &DCI) const {
3343   EVT VT = N->getValueType(0);
3344 
3345   if (!Subtarget->hasMulI24() || VT.isVector())
3346     return SDValue();
3347 
3348   SelectionDAG &DAG = DCI.DAG;
3349   SDLoc DL(N);
3350 
3351   SDValue N0 = N->getOperand(0);
3352   SDValue N1 = N->getOperand(1);
3353 
3354   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3355     return SDValue();
3356 
3357   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3358   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3359 
3360   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3361   DCI.AddToWorklist(Mulhi.getNode());
3362   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3363 }
3364 
3365 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3366                                                   DAGCombinerInfo &DCI) const {
3367   EVT VT = N->getValueType(0);
3368 
3369   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3370     return SDValue();
3371 
3372   SelectionDAG &DAG = DCI.DAG;
3373   SDLoc DL(N);
3374 
3375   SDValue N0 = N->getOperand(0);
3376   SDValue N1 = N->getOperand(1);
3377 
3378   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3379     return SDValue();
3380 
3381   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3382   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3383 
3384   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3385   DCI.AddToWorklist(Mulhi.getNode());
3386   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3387 }
3388 
3389 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3390   SDNode *N, DAGCombinerInfo &DCI) const {
3391   SelectionDAG &DAG = DCI.DAG;
3392 
3393   // Simplify demanded bits before splitting into multiple users.
3394   if (SDValue V = simplifyI24(N, DCI))
3395     return V;
3396 
3397   SDValue N0 = N->getOperand(0);
3398   SDValue N1 = N->getOperand(1);
3399 
3400   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3401 
3402   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3403   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3404 
3405   SDLoc SL(N);
3406 
3407   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3408   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3409   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3410 }
3411 
3412 static bool isNegativeOne(SDValue Val) {
3413   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3414     return C->isAllOnesValue();
3415   return false;
3416 }
3417 
3418 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3419                                           SDValue Op,
3420                                           const SDLoc &DL,
3421                                           unsigned Opc) const {
3422   EVT VT = Op.getValueType();
3423   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3424   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3425                               LegalVT != MVT::i16))
3426     return SDValue();
3427 
3428   if (VT != MVT::i32)
3429     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3430 
3431   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3432   if (VT != MVT::i32)
3433     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3434 
3435   return FFBX;
3436 }
3437 
3438 // The native instructions return -1 on 0 input. Optimize out a select that
3439 // produces -1 on 0.
3440 //
3441 // TODO: If zero is not undef, we could also do this if the output is compared
3442 // against the bitwidth.
3443 //
3444 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3445 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3446                                                  SDValue LHS, SDValue RHS,
3447                                                  DAGCombinerInfo &DCI) const {
3448   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3449   if (!CmpRhs || !CmpRhs->isNullValue())
3450     return SDValue();
3451 
3452   SelectionDAG &DAG = DCI.DAG;
3453   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3454   SDValue CmpLHS = Cond.getOperand(0);
3455 
3456   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3457                                            AMDGPUISD::FFBH_U32;
3458 
3459   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3460   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3461   if (CCOpcode == ISD::SETEQ &&
3462       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3463       RHS.getOperand(0) == CmpLHS &&
3464       isNegativeOne(LHS)) {
3465     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3466   }
3467 
3468   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3469   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3470   if (CCOpcode == ISD::SETNE &&
3471       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3472       LHS.getOperand(0) == CmpLHS &&
3473       isNegativeOne(RHS)) {
3474     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3475   }
3476 
3477   return SDValue();
3478 }
3479 
3480 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3481                                          unsigned Op,
3482                                          const SDLoc &SL,
3483                                          SDValue Cond,
3484                                          SDValue N1,
3485                                          SDValue N2) {
3486   SelectionDAG &DAG = DCI.DAG;
3487   EVT VT = N1.getValueType();
3488 
3489   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3490                                   N1.getOperand(0), N2.getOperand(0));
3491   DCI.AddToWorklist(NewSelect.getNode());
3492   return DAG.getNode(Op, SL, VT, NewSelect);
3493 }
3494 
3495 // Pull a free FP operation out of a select so it may fold into uses.
3496 //
3497 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3498 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3499 //
3500 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3501 // select c, (fabs x), +k -> fabs (select c, x, k)
3502 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3503                                     SDValue N) {
3504   SelectionDAG &DAG = DCI.DAG;
3505   SDValue Cond = N.getOperand(0);
3506   SDValue LHS = N.getOperand(1);
3507   SDValue RHS = N.getOperand(2);
3508 
3509   EVT VT = N.getValueType();
3510   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3511       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3512     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3513                                      SDLoc(N), Cond, LHS, RHS);
3514   }
3515 
3516   bool Inv = false;
3517   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3518     std::swap(LHS, RHS);
3519     Inv = true;
3520   }
3521 
3522   // TODO: Support vector constants.
3523   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3524   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3525     SDLoc SL(N);
3526     // If one side is an fneg/fabs and the other is a constant, we can push the
3527     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3528     SDValue NewLHS = LHS.getOperand(0);
3529     SDValue NewRHS = RHS;
3530 
3531     // Careful: if the neg can be folded up, don't try to pull it back down.
3532     bool ShouldFoldNeg = true;
3533 
3534     if (NewLHS.hasOneUse()) {
3535       unsigned Opc = NewLHS.getOpcode();
3536       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3537         ShouldFoldNeg = false;
3538       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3539         ShouldFoldNeg = false;
3540     }
3541 
3542     if (ShouldFoldNeg) {
3543       if (LHS.getOpcode() == ISD::FNEG)
3544         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3545       else if (CRHS->isNegative())
3546         return SDValue();
3547 
3548       if (Inv)
3549         std::swap(NewLHS, NewRHS);
3550 
3551       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3552                                       Cond, NewLHS, NewRHS);
3553       DCI.AddToWorklist(NewSelect.getNode());
3554       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3555     }
3556   }
3557 
3558   return SDValue();
3559 }
3560 
3561 
3562 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3563                                                    DAGCombinerInfo &DCI) const {
3564   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3565     return Folded;
3566 
3567   SDValue Cond = N->getOperand(0);
3568   if (Cond.getOpcode() != ISD::SETCC)
3569     return SDValue();
3570 
3571   EVT VT = N->getValueType(0);
3572   SDValue LHS = Cond.getOperand(0);
3573   SDValue RHS = Cond.getOperand(1);
3574   SDValue CC = Cond.getOperand(2);
3575 
3576   SDValue True = N->getOperand(1);
3577   SDValue False = N->getOperand(2);
3578 
3579   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3580     SelectionDAG &DAG = DCI.DAG;
3581     if (DAG.isConstantValueOfAnyType(True) &&
3582         !DAG.isConstantValueOfAnyType(False)) {
3583       // Swap cmp + select pair to move constant to false input.
3584       // This will allow using VOPC cndmasks more often.
3585       // select (setcc x, y), k, x -> select (setccinv x, y), x, k
3586 
3587       SDLoc SL(N);
3588       ISD::CondCode NewCC =
3589           getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), LHS.getValueType());
3590 
3591       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3592       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3593     }
3594 
3595     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3596       SDValue MinMax
3597         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3598       // Revisit this node so we can catch min3/max3/med3 patterns.
3599       //DCI.AddToWorklist(MinMax.getNode());
3600       return MinMax;
3601     }
3602   }
3603 
3604   // There's no reason to not do this if the condition has other uses.
3605   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3606 }
3607 
3608 static bool isInv2Pi(const APFloat &APF) {
3609   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3610   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3611   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3612 
3613   return APF.bitwiseIsEqual(KF16) ||
3614          APF.bitwiseIsEqual(KF32) ||
3615          APF.bitwiseIsEqual(KF64);
3616 }
3617 
3618 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3619 // additional cost to negate them.
3620 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3621   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3622     if (C->isZero() && !C->isNegative())
3623       return true;
3624 
3625     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3626       return true;
3627   }
3628 
3629   return false;
3630 }
3631 
3632 static unsigned inverseMinMax(unsigned Opc) {
3633   switch (Opc) {
3634   case ISD::FMAXNUM:
3635     return ISD::FMINNUM;
3636   case ISD::FMINNUM:
3637     return ISD::FMAXNUM;
3638   case ISD::FMAXNUM_IEEE:
3639     return ISD::FMINNUM_IEEE;
3640   case ISD::FMINNUM_IEEE:
3641     return ISD::FMAXNUM_IEEE;
3642   case AMDGPUISD::FMAX_LEGACY:
3643     return AMDGPUISD::FMIN_LEGACY;
3644   case AMDGPUISD::FMIN_LEGACY:
3645     return  AMDGPUISD::FMAX_LEGACY;
3646   default:
3647     llvm_unreachable("invalid min/max opcode");
3648   }
3649 }
3650 
3651 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3652                                                  DAGCombinerInfo &DCI) const {
3653   SelectionDAG &DAG = DCI.DAG;
3654   SDValue N0 = N->getOperand(0);
3655   EVT VT = N->getValueType(0);
3656 
3657   unsigned Opc = N0.getOpcode();
3658 
3659   // If the input has multiple uses and we can either fold the negate down, or
3660   // the other uses cannot, give up. This both prevents unprofitable
3661   // transformations and infinite loops: we won't repeatedly try to fold around
3662   // a negate that has no 'good' form.
3663   if (N0.hasOneUse()) {
3664     // This may be able to fold into the source, but at a code size cost. Don't
3665     // fold if the fold into the user is free.
3666     if (allUsesHaveSourceMods(N, 0))
3667       return SDValue();
3668   } else {
3669     if (fnegFoldsIntoOp(Opc) &&
3670         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3671       return SDValue();
3672   }
3673 
3674   SDLoc SL(N);
3675   switch (Opc) {
3676   case ISD::FADD: {
3677     if (!mayIgnoreSignedZero(N0))
3678       return SDValue();
3679 
3680     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3681     SDValue LHS = N0.getOperand(0);
3682     SDValue RHS = N0.getOperand(1);
3683 
3684     if (LHS.getOpcode() != ISD::FNEG)
3685       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3686     else
3687       LHS = LHS.getOperand(0);
3688 
3689     if (RHS.getOpcode() != ISD::FNEG)
3690       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3691     else
3692       RHS = RHS.getOperand(0);
3693 
3694     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3695     if (Res.getOpcode() != ISD::FADD)
3696       return SDValue(); // Op got folded away.
3697     if (!N0.hasOneUse())
3698       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3699     return Res;
3700   }
3701   case ISD::FMUL:
3702   case AMDGPUISD::FMUL_LEGACY: {
3703     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3704     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3705     SDValue LHS = N0.getOperand(0);
3706     SDValue RHS = N0.getOperand(1);
3707 
3708     if (LHS.getOpcode() == ISD::FNEG)
3709       LHS = LHS.getOperand(0);
3710     else if (RHS.getOpcode() == ISD::FNEG)
3711       RHS = RHS.getOperand(0);
3712     else
3713       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3714 
3715     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3716     if (Res.getOpcode() != Opc)
3717       return SDValue(); // Op got folded away.
3718     if (!N0.hasOneUse())
3719       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3720     return Res;
3721   }
3722   case ISD::FMA:
3723   case ISD::FMAD: {
3724     if (!mayIgnoreSignedZero(N0))
3725       return SDValue();
3726 
3727     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3728     SDValue LHS = N0.getOperand(0);
3729     SDValue MHS = N0.getOperand(1);
3730     SDValue RHS = N0.getOperand(2);
3731 
3732     if (LHS.getOpcode() == ISD::FNEG)
3733       LHS = LHS.getOperand(0);
3734     else if (MHS.getOpcode() == ISD::FNEG)
3735       MHS = MHS.getOperand(0);
3736     else
3737       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3738 
3739     if (RHS.getOpcode() != ISD::FNEG)
3740       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3741     else
3742       RHS = RHS.getOperand(0);
3743 
3744     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3745     if (Res.getOpcode() != Opc)
3746       return SDValue(); // Op got folded away.
3747     if (!N0.hasOneUse())
3748       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3749     return Res;
3750   }
3751   case ISD::FMAXNUM:
3752   case ISD::FMINNUM:
3753   case ISD::FMAXNUM_IEEE:
3754   case ISD::FMINNUM_IEEE:
3755   case AMDGPUISD::FMAX_LEGACY:
3756   case AMDGPUISD::FMIN_LEGACY: {
3757     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3758     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3759     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3760     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3761 
3762     SDValue LHS = N0.getOperand(0);
3763     SDValue RHS = N0.getOperand(1);
3764 
3765     // 0 doesn't have a negated inline immediate.
3766     // TODO: This constant check should be generalized to other operations.
3767     if (isConstantCostlierToNegate(RHS))
3768       return SDValue();
3769 
3770     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3771     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3772     unsigned Opposite = inverseMinMax(Opc);
3773 
3774     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3775     if (Res.getOpcode() != Opposite)
3776       return SDValue(); // Op got folded away.
3777     if (!N0.hasOneUse())
3778       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3779     return Res;
3780   }
3781   case AMDGPUISD::FMED3: {
3782     SDValue Ops[3];
3783     for (unsigned I = 0; I < 3; ++I)
3784       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3785 
3786     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3787     if (Res.getOpcode() != AMDGPUISD::FMED3)
3788       return SDValue(); // Op got folded away.
3789     if (!N0.hasOneUse())
3790       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3791     return Res;
3792   }
3793   case ISD::FP_EXTEND:
3794   case ISD::FTRUNC:
3795   case ISD::FRINT:
3796   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3797   case ISD::FSIN:
3798   case ISD::FCANONICALIZE:
3799   case AMDGPUISD::RCP:
3800   case AMDGPUISD::RCP_LEGACY:
3801   case AMDGPUISD::RCP_IFLAG:
3802   case AMDGPUISD::SIN_HW: {
3803     SDValue CvtSrc = N0.getOperand(0);
3804     if (CvtSrc.getOpcode() == ISD::FNEG) {
3805       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3806       // (fneg (rcp (fneg x))) -> (rcp x)
3807       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3808     }
3809 
3810     if (!N0.hasOneUse())
3811       return SDValue();
3812 
3813     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3814     // (fneg (rcp x)) -> (rcp (fneg x))
3815     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3816     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3817   }
3818   case ISD::FP_ROUND: {
3819     SDValue CvtSrc = N0.getOperand(0);
3820 
3821     if (CvtSrc.getOpcode() == ISD::FNEG) {
3822       // (fneg (fp_round (fneg x))) -> (fp_round x)
3823       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3824                          CvtSrc.getOperand(0), N0.getOperand(1));
3825     }
3826 
3827     if (!N0.hasOneUse())
3828       return SDValue();
3829 
3830     // (fneg (fp_round x)) -> (fp_round (fneg x))
3831     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3832     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3833   }
3834   case ISD::FP16_TO_FP: {
3835     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3836     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3837     // Put the fneg back as a legal source operation that can be matched later.
3838     SDLoc SL(N);
3839 
3840     SDValue Src = N0.getOperand(0);
3841     EVT SrcVT = Src.getValueType();
3842 
3843     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3844     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3845                                   DAG.getConstant(0x8000, SL, SrcVT));
3846     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3847   }
3848   default:
3849     return SDValue();
3850   }
3851 }
3852 
3853 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3854                                                  DAGCombinerInfo &DCI) const {
3855   SelectionDAG &DAG = DCI.DAG;
3856   SDValue N0 = N->getOperand(0);
3857 
3858   if (!N0.hasOneUse())
3859     return SDValue();
3860 
3861   switch (N0.getOpcode()) {
3862   case ISD::FP16_TO_FP: {
3863     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3864     SDLoc SL(N);
3865     SDValue Src = N0.getOperand(0);
3866     EVT SrcVT = Src.getValueType();
3867 
3868     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3869     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3870                                   DAG.getConstant(0x7fff, SL, SrcVT));
3871     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3872   }
3873   default:
3874     return SDValue();
3875   }
3876 }
3877 
3878 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3879                                                 DAGCombinerInfo &DCI) const {
3880   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3881   if (!CFP)
3882     return SDValue();
3883 
3884   // XXX - Should this flush denormals?
3885   const APFloat &Val = CFP->getValueAPF();
3886   APFloat One(Val.getSemantics(), "1.0");
3887   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3888 }
3889 
3890 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3891                                                 DAGCombinerInfo &DCI) const {
3892   SelectionDAG &DAG = DCI.DAG;
3893   SDLoc DL(N);
3894 
3895   switch(N->getOpcode()) {
3896   default:
3897     break;
3898   case ISD::BITCAST: {
3899     EVT DestVT = N->getValueType(0);
3900 
3901     // Push casts through vector builds. This helps avoid emitting a large
3902     // number of copies when materializing floating point vector constants.
3903     //
3904     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3905     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3906     if (DestVT.isVector()) {
3907       SDValue Src = N->getOperand(0);
3908       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3909         EVT SrcVT = Src.getValueType();
3910         unsigned NElts = DestVT.getVectorNumElements();
3911 
3912         if (SrcVT.getVectorNumElements() == NElts) {
3913           EVT DestEltVT = DestVT.getVectorElementType();
3914 
3915           SmallVector<SDValue, 8> CastedElts;
3916           SDLoc SL(N);
3917           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3918             SDValue Elt = Src.getOperand(I);
3919             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3920           }
3921 
3922           return DAG.getBuildVector(DestVT, SL, CastedElts);
3923         }
3924       }
3925     }
3926 
3927     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3928       break;
3929 
3930     // Fold bitcasts of constants.
3931     //
3932     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3933     // TODO: Generalize and move to DAGCombiner
3934     SDValue Src = N->getOperand(0);
3935     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3936       if (Src.getValueType() == MVT::i64) {
3937         SDLoc SL(N);
3938         uint64_t CVal = C->getZExtValue();
3939         SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3940                                  DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3941                                  DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3942         return DAG.getNode(ISD::BITCAST, SL, DestVT, BV);
3943       }
3944     }
3945 
3946     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3947       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3948       SDLoc SL(N);
3949       uint64_t CVal = Val.getZExtValue();
3950       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3951                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3952                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3953 
3954       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3955     }
3956 
3957     break;
3958   }
3959   case ISD::SHL: {
3960     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3961       break;
3962 
3963     return performShlCombine(N, DCI);
3964   }
3965   case ISD::SRL: {
3966     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3967       break;
3968 
3969     return performSrlCombine(N, DCI);
3970   }
3971   case ISD::SRA: {
3972     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3973       break;
3974 
3975     return performSraCombine(N, DCI);
3976   }
3977   case ISD::TRUNCATE:
3978     return performTruncateCombine(N, DCI);
3979   case ISD::MUL:
3980     return performMulCombine(N, DCI);
3981   case ISD::MULHS:
3982     return performMulhsCombine(N, DCI);
3983   case ISD::MULHU:
3984     return performMulhuCombine(N, DCI);
3985   case AMDGPUISD::MUL_I24:
3986   case AMDGPUISD::MUL_U24:
3987   case AMDGPUISD::MULHI_I24:
3988   case AMDGPUISD::MULHI_U24: {
3989     if (SDValue V = simplifyI24(N, DCI))
3990       return V;
3991     return SDValue();
3992   }
3993   case AMDGPUISD::MUL_LOHI_I24:
3994   case AMDGPUISD::MUL_LOHI_U24:
3995     return performMulLoHi24Combine(N, DCI);
3996   case ISD::SELECT:
3997     return performSelectCombine(N, DCI);
3998   case ISD::FNEG:
3999     return performFNegCombine(N, DCI);
4000   case ISD::FABS:
4001     return performFAbsCombine(N, DCI);
4002   case AMDGPUISD::BFE_I32:
4003   case AMDGPUISD::BFE_U32: {
4004     assert(!N->getValueType(0).isVector() &&
4005            "Vector handling of BFE not implemented");
4006     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
4007     if (!Width)
4008       break;
4009 
4010     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
4011     if (WidthVal == 0)
4012       return DAG.getConstant(0, DL, MVT::i32);
4013 
4014     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
4015     if (!Offset)
4016       break;
4017 
4018     SDValue BitsFrom = N->getOperand(0);
4019     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
4020 
4021     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
4022 
4023     if (OffsetVal == 0) {
4024       // This is already sign / zero extended, so try to fold away extra BFEs.
4025       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
4026 
4027       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
4028       if (OpSignBits >= SignBits)
4029         return BitsFrom;
4030 
4031       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
4032       if (Signed) {
4033         // This is a sign_extend_inreg. Replace it to take advantage of existing
4034         // DAG Combines. If not eliminated, we will match back to BFE during
4035         // selection.
4036 
4037         // TODO: The sext_inreg of extended types ends, although we can could
4038         // handle them in a single BFE.
4039         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
4040                            DAG.getValueType(SmallVT));
4041       }
4042 
4043       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
4044     }
4045 
4046     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
4047       if (Signed) {
4048         return constantFoldBFE<int32_t>(DAG,
4049                                         CVal->getSExtValue(),
4050                                         OffsetVal,
4051                                         WidthVal,
4052                                         DL);
4053       }
4054 
4055       return constantFoldBFE<uint32_t>(DAG,
4056                                        CVal->getZExtValue(),
4057                                        OffsetVal,
4058                                        WidthVal,
4059                                        DL);
4060     }
4061 
4062     if ((OffsetVal + WidthVal) >= 32 &&
4063         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
4064       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
4065       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
4066                          BitsFrom, ShiftVal);
4067     }
4068 
4069     if (BitsFrom.hasOneUse()) {
4070       APInt Demanded = APInt::getBitsSet(32,
4071                                          OffsetVal,
4072                                          OffsetVal + WidthVal);
4073 
4074       KnownBits Known;
4075       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
4076                                             !DCI.isBeforeLegalizeOps());
4077       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
4078       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
4079           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
4080         DCI.CommitTargetLoweringOpt(TLO);
4081       }
4082     }
4083 
4084     break;
4085   }
4086   case ISD::LOAD:
4087     return performLoadCombine(N, DCI);
4088   case ISD::STORE:
4089     return performStoreCombine(N, DCI);
4090   case AMDGPUISD::RCP:
4091   case AMDGPUISD::RCP_IFLAG:
4092     return performRcpCombine(N, DCI);
4093   case ISD::AssertZext:
4094   case ISD::AssertSext:
4095     return performAssertSZExtCombine(N, DCI);
4096   case ISD::INTRINSIC_WO_CHAIN:
4097     return performIntrinsicWOChainCombine(N, DCI);
4098   }
4099   return SDValue();
4100 }
4101 
4102 //===----------------------------------------------------------------------===//
4103 // Helper functions
4104 //===----------------------------------------------------------------------===//
4105 
4106 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
4107                                                    const TargetRegisterClass *RC,
4108                                                    unsigned Reg, EVT VT,
4109                                                    const SDLoc &SL,
4110                                                    bool RawReg) const {
4111   MachineFunction &MF = DAG.getMachineFunction();
4112   MachineRegisterInfo &MRI = MF.getRegInfo();
4113   unsigned VReg;
4114 
4115   if (!MRI.isLiveIn(Reg)) {
4116     VReg = MRI.createVirtualRegister(RC);
4117     MRI.addLiveIn(Reg, VReg);
4118   } else {
4119     VReg = MRI.getLiveInVirtReg(Reg);
4120   }
4121 
4122   if (RawReg)
4123     return DAG.getRegister(VReg, VT);
4124 
4125   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
4126 }
4127 
4128 // This may be called multiple times, and nothing prevents creating multiple
4129 // objects at the same offset. See if we already defined this object.
4130 static int getOrCreateFixedStackObject(MachineFrameInfo &MFI, unsigned Size,
4131                                        int64_t Offset) {
4132   for (int I = MFI.getObjectIndexBegin(); I < 0; ++I) {
4133     if (MFI.getObjectOffset(I) == Offset) {
4134       assert(MFI.getObjectSize(I) == Size);
4135       return I;
4136     }
4137   }
4138 
4139   return MFI.CreateFixedObject(Size, Offset, true);
4140 }
4141 
4142 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
4143                                                   EVT VT,
4144                                                   const SDLoc &SL,
4145                                                   int64_t Offset) const {
4146   MachineFunction &MF = DAG.getMachineFunction();
4147   MachineFrameInfo &MFI = MF.getFrameInfo();
4148   int FI = getOrCreateFixedStackObject(MFI, VT.getStoreSize(), Offset);
4149 
4150   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4151   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4152 
4153   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4154                      MachineMemOperand::MODereferenceable |
4155                      MachineMemOperand::MOInvariant);
4156 }
4157 
4158 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4159                                                    const SDLoc &SL,
4160                                                    SDValue Chain,
4161                                                    SDValue ArgVal,
4162                                                    int64_t Offset) const {
4163   MachineFunction &MF = DAG.getMachineFunction();
4164   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4165 
4166   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4167   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4168                                MachineMemOperand::MODereferenceable);
4169   return Store;
4170 }
4171 
4172 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4173                                              const TargetRegisterClass *RC,
4174                                              EVT VT, const SDLoc &SL,
4175                                              const ArgDescriptor &Arg) const {
4176   assert(Arg && "Attempting to load missing argument");
4177 
4178   SDValue V = Arg.isRegister() ?
4179     CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL) :
4180     loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4181 
4182   if (!Arg.isMasked())
4183     return V;
4184 
4185   unsigned Mask = Arg.getMask();
4186   unsigned Shift = countTrailingZeros<unsigned>(Mask);
4187   V = DAG.getNode(ISD::SRL, SL, VT, V,
4188                   DAG.getShiftAmountConstant(Shift, VT, SL));
4189   return DAG.getNode(ISD::AND, SL, VT, V,
4190                      DAG.getConstant(Mask >> Shift, SL, VT));
4191 }
4192 
4193 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4194     const MachineFunction &MF, const ImplicitParameter Param) const {
4195   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4196   const AMDGPUSubtarget &ST =
4197       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4198   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4199   const Align Alignment = ST.getAlignmentForImplicitArgPtr();
4200   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4201                        ExplicitArgOffset;
4202   switch (Param) {
4203   case GRID_DIM:
4204     return ArgOffset;
4205   case GRID_OFFSET:
4206     return ArgOffset + 4;
4207   }
4208   llvm_unreachable("unexpected implicit parameter type");
4209 }
4210 
4211 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4212 
4213 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4214   switch ((AMDGPUISD::NodeType)Opcode) {
4215   case AMDGPUISD::FIRST_NUMBER: break;
4216   // AMDIL DAG nodes
4217   NODE_NAME_CASE(UMUL);
4218   NODE_NAME_CASE(BRANCH_COND);
4219 
4220   // AMDGPU DAG nodes
4221   NODE_NAME_CASE(IF)
4222   NODE_NAME_CASE(ELSE)
4223   NODE_NAME_CASE(LOOP)
4224   NODE_NAME_CASE(CALL)
4225   NODE_NAME_CASE(TC_RETURN)
4226   NODE_NAME_CASE(TRAP)
4227   NODE_NAME_CASE(RET_FLAG)
4228   NODE_NAME_CASE(RETURN_TO_EPILOG)
4229   NODE_NAME_CASE(ENDPGM)
4230   NODE_NAME_CASE(DWORDADDR)
4231   NODE_NAME_CASE(FRACT)
4232   NODE_NAME_CASE(SETCC)
4233   NODE_NAME_CASE(SETREG)
4234   NODE_NAME_CASE(DENORM_MODE)
4235   NODE_NAME_CASE(FMA_W_CHAIN)
4236   NODE_NAME_CASE(FMUL_W_CHAIN)
4237   NODE_NAME_CASE(CLAMP)
4238   NODE_NAME_CASE(COS_HW)
4239   NODE_NAME_CASE(SIN_HW)
4240   NODE_NAME_CASE(FMAX_LEGACY)
4241   NODE_NAME_CASE(FMIN_LEGACY)
4242   NODE_NAME_CASE(FMAX3)
4243   NODE_NAME_CASE(SMAX3)
4244   NODE_NAME_CASE(UMAX3)
4245   NODE_NAME_CASE(FMIN3)
4246   NODE_NAME_CASE(SMIN3)
4247   NODE_NAME_CASE(UMIN3)
4248   NODE_NAME_CASE(FMED3)
4249   NODE_NAME_CASE(SMED3)
4250   NODE_NAME_CASE(UMED3)
4251   NODE_NAME_CASE(FDOT2)
4252   NODE_NAME_CASE(URECIP)
4253   NODE_NAME_CASE(DIV_SCALE)
4254   NODE_NAME_CASE(DIV_FMAS)
4255   NODE_NAME_CASE(DIV_FIXUP)
4256   NODE_NAME_CASE(FMAD_FTZ)
4257   NODE_NAME_CASE(TRIG_PREOP)
4258   NODE_NAME_CASE(RCP)
4259   NODE_NAME_CASE(RSQ)
4260   NODE_NAME_CASE(RCP_LEGACY)
4261   NODE_NAME_CASE(RSQ_LEGACY)
4262   NODE_NAME_CASE(RCP_IFLAG)
4263   NODE_NAME_CASE(FMUL_LEGACY)
4264   NODE_NAME_CASE(RSQ_CLAMP)
4265   NODE_NAME_CASE(LDEXP)
4266   NODE_NAME_CASE(FP_CLASS)
4267   NODE_NAME_CASE(DOT4)
4268   NODE_NAME_CASE(CARRY)
4269   NODE_NAME_CASE(BORROW)
4270   NODE_NAME_CASE(BFE_U32)
4271   NODE_NAME_CASE(BFE_I32)
4272   NODE_NAME_CASE(BFI)
4273   NODE_NAME_CASE(BFM)
4274   NODE_NAME_CASE(FFBH_U32)
4275   NODE_NAME_CASE(FFBH_I32)
4276   NODE_NAME_CASE(FFBL_B32)
4277   NODE_NAME_CASE(MUL_U24)
4278   NODE_NAME_CASE(MUL_I24)
4279   NODE_NAME_CASE(MULHI_U24)
4280   NODE_NAME_CASE(MULHI_I24)
4281   NODE_NAME_CASE(MUL_LOHI_U24)
4282   NODE_NAME_CASE(MUL_LOHI_I24)
4283   NODE_NAME_CASE(MAD_U24)
4284   NODE_NAME_CASE(MAD_I24)
4285   NODE_NAME_CASE(MAD_I64_I32)
4286   NODE_NAME_CASE(MAD_U64_U32)
4287   NODE_NAME_CASE(PERM)
4288   NODE_NAME_CASE(TEXTURE_FETCH)
4289   NODE_NAME_CASE(R600_EXPORT)
4290   NODE_NAME_CASE(CONST_ADDRESS)
4291   NODE_NAME_CASE(REGISTER_LOAD)
4292   NODE_NAME_CASE(REGISTER_STORE)
4293   NODE_NAME_CASE(SAMPLE)
4294   NODE_NAME_CASE(SAMPLEB)
4295   NODE_NAME_CASE(SAMPLED)
4296   NODE_NAME_CASE(SAMPLEL)
4297   NODE_NAME_CASE(CVT_F32_UBYTE0)
4298   NODE_NAME_CASE(CVT_F32_UBYTE1)
4299   NODE_NAME_CASE(CVT_F32_UBYTE2)
4300   NODE_NAME_CASE(CVT_F32_UBYTE3)
4301   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4302   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4303   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4304   NODE_NAME_CASE(CVT_PK_I16_I32)
4305   NODE_NAME_CASE(CVT_PK_U16_U32)
4306   NODE_NAME_CASE(FP_TO_FP16)
4307   NODE_NAME_CASE(FP16_ZEXT)
4308   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4309   NODE_NAME_CASE(CONST_DATA_PTR)
4310   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4311   NODE_NAME_CASE(LDS)
4312   NODE_NAME_CASE(DUMMY_CHAIN)
4313   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4314   NODE_NAME_CASE(LOAD_D16_HI)
4315   NODE_NAME_CASE(LOAD_D16_LO)
4316   NODE_NAME_CASE(LOAD_D16_HI_I8)
4317   NODE_NAME_CASE(LOAD_D16_HI_U8)
4318   NODE_NAME_CASE(LOAD_D16_LO_I8)
4319   NODE_NAME_CASE(LOAD_D16_LO_U8)
4320   NODE_NAME_CASE(STORE_MSKOR)
4321   NODE_NAME_CASE(LOAD_CONSTANT)
4322   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4323   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4324   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4325   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4326   NODE_NAME_CASE(DS_ORDERED_COUNT)
4327   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4328   NODE_NAME_CASE(ATOMIC_INC)
4329   NODE_NAME_CASE(ATOMIC_DEC)
4330   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4331   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4332   NODE_NAME_CASE(BUFFER_LOAD)
4333   NODE_NAME_CASE(BUFFER_LOAD_UBYTE)
4334   NODE_NAME_CASE(BUFFER_LOAD_USHORT)
4335   NODE_NAME_CASE(BUFFER_LOAD_BYTE)
4336   NODE_NAME_CASE(BUFFER_LOAD_SHORT)
4337   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4338   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4339   NODE_NAME_CASE(SBUFFER_LOAD)
4340   NODE_NAME_CASE(BUFFER_STORE)
4341   NODE_NAME_CASE(BUFFER_STORE_BYTE)
4342   NODE_NAME_CASE(BUFFER_STORE_SHORT)
4343   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4344   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4345   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4346   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4347   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4348   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4349   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4350   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4351   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4352   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4353   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4354   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4355   NODE_NAME_CASE(BUFFER_ATOMIC_INC)
4356   NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
4357   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4358   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
4359   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)
4360   NODE_NAME_CASE(ATOMIC_PK_FADD)
4361 
4362   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4363   }
4364   return nullptr;
4365 }
4366 
4367 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4368                                               SelectionDAG &DAG, int Enabled,
4369                                               int &RefinementSteps,
4370                                               bool &UseOneConstNR,
4371                                               bool Reciprocal) const {
4372   EVT VT = Operand.getValueType();
4373 
4374   if (VT == MVT::f32) {
4375     RefinementSteps = 0;
4376     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4377   }
4378 
4379   // TODO: There is also f64 rsq instruction, but the documentation is less
4380   // clear on its precision.
4381 
4382   return SDValue();
4383 }
4384 
4385 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4386                                                SelectionDAG &DAG, int Enabled,
4387                                                int &RefinementSteps) const {
4388   EVT VT = Operand.getValueType();
4389 
4390   if (VT == MVT::f32) {
4391     // Reciprocal, < 1 ulp error.
4392     //
4393     // This reciprocal approximation converges to < 0.5 ulp error with one
4394     // newton rhapson performed with two fused multiple adds (FMAs).
4395 
4396     RefinementSteps = 0;
4397     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4398   }
4399 
4400   // TODO: There is also f64 rcp instruction, but the documentation is less
4401   // clear on its precision.
4402 
4403   return SDValue();
4404 }
4405 
4406 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4407     const SDValue Op, KnownBits &Known,
4408     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4409 
4410   Known.resetAll(); // Don't know anything.
4411 
4412   unsigned Opc = Op.getOpcode();
4413 
4414   switch (Opc) {
4415   default:
4416     break;
4417   case AMDGPUISD::CARRY:
4418   case AMDGPUISD::BORROW: {
4419     Known.Zero = APInt::getHighBitsSet(32, 31);
4420     break;
4421   }
4422 
4423   case AMDGPUISD::BFE_I32:
4424   case AMDGPUISD::BFE_U32: {
4425     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4426     if (!CWidth)
4427       return;
4428 
4429     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4430 
4431     if (Opc == AMDGPUISD::BFE_U32)
4432       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4433 
4434     break;
4435   }
4436   case AMDGPUISD::FP_TO_FP16:
4437   case AMDGPUISD::FP16_ZEXT: {
4438     unsigned BitWidth = Known.getBitWidth();
4439 
4440     // High bits are zero.
4441     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4442     break;
4443   }
4444   case AMDGPUISD::MUL_U24:
4445   case AMDGPUISD::MUL_I24: {
4446     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4447     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4448     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4449                       RHSKnown.countMinTrailingZeros();
4450     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4451     // Skip extra check if all bits are known zeros.
4452     if (TrailZ >= 32)
4453       break;
4454 
4455     // Truncate to 24 bits.
4456     LHSKnown = LHSKnown.trunc(24);
4457     RHSKnown = RHSKnown.trunc(24);
4458 
4459     if (Opc == AMDGPUISD::MUL_I24) {
4460       unsigned LHSValBits = 24 - LHSKnown.countMinSignBits();
4461       unsigned RHSValBits = 24 - RHSKnown.countMinSignBits();
4462       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4463       if (MaxValBits >= 32)
4464         break;
4465       bool LHSNegative = LHSKnown.isNegative();
4466       bool LHSNonNegative = LHSKnown.isNonNegative();
4467       bool LHSPositive = LHSKnown.isStrictlyPositive();
4468       bool RHSNegative = RHSKnown.isNegative();
4469       bool RHSNonNegative = RHSKnown.isNonNegative();
4470       bool RHSPositive = RHSKnown.isStrictlyPositive();
4471 
4472       if ((LHSNonNegative && RHSNonNegative) || (LHSNegative && RHSNegative))
4473         Known.Zero.setHighBits(32 - MaxValBits);
4474       else if ((LHSNegative && RHSPositive) || (LHSPositive && RHSNegative))
4475         Known.One.setHighBits(32 - MaxValBits);
4476     } else {
4477       unsigned LHSValBits = 24 - LHSKnown.countMinLeadingZeros();
4478       unsigned RHSValBits = 24 - RHSKnown.countMinLeadingZeros();
4479       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4480       if (MaxValBits >= 32)
4481         break;
4482       Known.Zero.setHighBits(32 - MaxValBits);
4483     }
4484     break;
4485   }
4486   case AMDGPUISD::PERM: {
4487     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4488     if (!CMask)
4489       return;
4490 
4491     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4492     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4493     unsigned Sel = CMask->getZExtValue();
4494 
4495     for (unsigned I = 0; I < 32; I += 8) {
4496       unsigned SelBits = Sel & 0xff;
4497       if (SelBits < 4) {
4498         SelBits *= 8;
4499         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4500         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4501       } else if (SelBits < 7) {
4502         SelBits = (SelBits & 3) * 8;
4503         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4504         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4505       } else if (SelBits == 0x0c) {
4506         Known.Zero |= 0xFFull << I;
4507       } else if (SelBits > 0x0c) {
4508         Known.One |= 0xFFull << I;
4509       }
4510       Sel >>= 8;
4511     }
4512     break;
4513   }
4514   case AMDGPUISD::BUFFER_LOAD_UBYTE:  {
4515     Known.Zero.setHighBits(24);
4516     break;
4517   }
4518   case AMDGPUISD::BUFFER_LOAD_USHORT: {
4519     Known.Zero.setHighBits(16);
4520     break;
4521   }
4522   case AMDGPUISD::LDS: {
4523     auto GA = cast<GlobalAddressSDNode>(Op.getOperand(0).getNode());
4524     unsigned Align = GA->getGlobal()->getAlignment();
4525 
4526     Known.Zero.setHighBits(16);
4527     if (Align)
4528       Known.Zero.setLowBits(Log2_32(Align));
4529     break;
4530   }
4531   case ISD::INTRINSIC_WO_CHAIN: {
4532     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4533     switch (IID) {
4534     case Intrinsic::amdgcn_mbcnt_lo:
4535     case Intrinsic::amdgcn_mbcnt_hi: {
4536       const GCNSubtarget &ST =
4537           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4538       // These return at most the wavefront size - 1.
4539       unsigned Size = Op.getValueType().getSizeInBits();
4540       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4541       break;
4542     }
4543     default:
4544       break;
4545     }
4546   }
4547   }
4548 }
4549 
4550 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4551     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4552     unsigned Depth) const {
4553   switch (Op.getOpcode()) {
4554   case AMDGPUISD::BFE_I32: {
4555     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4556     if (!Width)
4557       return 1;
4558 
4559     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4560     if (!isNullConstant(Op.getOperand(1)))
4561       return SignBits;
4562 
4563     // TODO: Could probably figure something out with non-0 offsets.
4564     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4565     return std::max(SignBits, Op0SignBits);
4566   }
4567 
4568   case AMDGPUISD::BFE_U32: {
4569     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4570     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4571   }
4572 
4573   case AMDGPUISD::CARRY:
4574   case AMDGPUISD::BORROW:
4575     return 31;
4576   case AMDGPUISD::BUFFER_LOAD_BYTE:
4577     return 25;
4578   case AMDGPUISD::BUFFER_LOAD_SHORT:
4579     return 17;
4580   case AMDGPUISD::BUFFER_LOAD_UBYTE:
4581     return 24;
4582   case AMDGPUISD::BUFFER_LOAD_USHORT:
4583     return 16;
4584   case AMDGPUISD::FP_TO_FP16:
4585   case AMDGPUISD::FP16_ZEXT:
4586     return 16;
4587   default:
4588     return 1;
4589   }
4590 }
4591 
4592 unsigned AMDGPUTargetLowering::computeNumSignBitsForTargetInstr(
4593   GISelKnownBits &Analysis, Register R,
4594   const APInt &DemandedElts, const MachineRegisterInfo &MRI,
4595   unsigned Depth) const {
4596   const MachineInstr *MI = MRI.getVRegDef(R);
4597   if (!MI)
4598     return 1;
4599 
4600   // TODO: Check range metadata on MMO.
4601   switch (MI->getOpcode()) {
4602   case AMDGPU::G_AMDGPU_BUFFER_LOAD_SBYTE:
4603     return 25;
4604   case AMDGPU::G_AMDGPU_BUFFER_LOAD_SSHORT:
4605     return 17;
4606   case AMDGPU::G_AMDGPU_BUFFER_LOAD_UBYTE:
4607     return 24;
4608   case AMDGPU::G_AMDGPU_BUFFER_LOAD_USHORT:
4609     return 16;
4610   default:
4611     return 1;
4612   }
4613 }
4614 
4615 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4616                                                         const SelectionDAG &DAG,
4617                                                         bool SNaN,
4618                                                         unsigned Depth) const {
4619   unsigned Opcode = Op.getOpcode();
4620   switch (Opcode) {
4621   case AMDGPUISD::FMIN_LEGACY:
4622   case AMDGPUISD::FMAX_LEGACY: {
4623     if (SNaN)
4624       return true;
4625 
4626     // TODO: Can check no nans on one of the operands for each one, but which
4627     // one?
4628     return false;
4629   }
4630   case AMDGPUISD::FMUL_LEGACY:
4631   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4632     if (SNaN)
4633       return true;
4634     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4635            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4636   }
4637   case AMDGPUISD::FMED3:
4638   case AMDGPUISD::FMIN3:
4639   case AMDGPUISD::FMAX3:
4640   case AMDGPUISD::FMAD_FTZ: {
4641     if (SNaN)
4642       return true;
4643     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4644            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4645            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4646   }
4647   case AMDGPUISD::CVT_F32_UBYTE0:
4648   case AMDGPUISD::CVT_F32_UBYTE1:
4649   case AMDGPUISD::CVT_F32_UBYTE2:
4650   case AMDGPUISD::CVT_F32_UBYTE3:
4651     return true;
4652 
4653   case AMDGPUISD::RCP:
4654   case AMDGPUISD::RSQ:
4655   case AMDGPUISD::RCP_LEGACY:
4656   case AMDGPUISD::RSQ_LEGACY:
4657   case AMDGPUISD::RSQ_CLAMP: {
4658     if (SNaN)
4659       return true;
4660 
4661     // TODO: Need is known positive check.
4662     return false;
4663   }
4664   case AMDGPUISD::LDEXP:
4665   case AMDGPUISD::FRACT: {
4666     if (SNaN)
4667       return true;
4668     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4669   }
4670   case AMDGPUISD::DIV_SCALE:
4671   case AMDGPUISD::DIV_FMAS:
4672   case AMDGPUISD::DIV_FIXUP:
4673   case AMDGPUISD::TRIG_PREOP:
4674     // TODO: Refine on operands.
4675     return SNaN;
4676   case AMDGPUISD::SIN_HW:
4677   case AMDGPUISD::COS_HW: {
4678     // TODO: Need check for infinity
4679     return SNaN;
4680   }
4681   case ISD::INTRINSIC_WO_CHAIN: {
4682     unsigned IntrinsicID
4683       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4684     // TODO: Handle more intrinsics
4685     switch (IntrinsicID) {
4686     case Intrinsic::amdgcn_cubeid:
4687       return true;
4688 
4689     case Intrinsic::amdgcn_frexp_mant: {
4690       if (SNaN)
4691         return true;
4692       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4693     }
4694     case Intrinsic::amdgcn_cvt_pkrtz: {
4695       if (SNaN)
4696         return true;
4697       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4698              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4699     }
4700     case Intrinsic::amdgcn_fdot2:
4701       // TODO: Refine on operand
4702       return SNaN;
4703     default:
4704       return false;
4705     }
4706   }
4707   default:
4708     return false;
4709   }
4710 }
4711 
4712 TargetLowering::AtomicExpansionKind
4713 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4714   switch (RMW->getOperation()) {
4715   case AtomicRMWInst::Nand:
4716   case AtomicRMWInst::FAdd:
4717   case AtomicRMWInst::FSub:
4718     return AtomicExpansionKind::CmpXChg;
4719   default:
4720     return AtomicExpansionKind::None;
4721   }
4722 }
4723