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 "AMDGPURegisterInfo.h"
20 #include "AMDGPUSubtarget.h"
21 #include "AMDGPUTargetMachine.h"
22 #include "Utils/AMDGPUBaseInfo.h"
23 #include "R600MachineFunctionInfo.h"
24 #include "SIInstrInfo.h"
25 #include "SIMachineFunctionInfo.h"
26 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
27 #include "llvm/CodeGen/Analysis.h"
28 #include "llvm/CodeGen/CallingConvLower.h"
29 #include "llvm/CodeGen/MachineFunction.h"
30 #include "llvm/CodeGen/MachineRegisterInfo.h"
31 #include "llvm/CodeGen/SelectionDAG.h"
32 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
33 #include "llvm/IR/DataLayout.h"
34 #include "llvm/IR/DiagnosticInfo.h"
35 #include "llvm/Support/KnownBits.h"
36 #include "llvm/Support/MathExtras.h"
37 using namespace llvm;
38 
39 #include "AMDGPUGenCallingConv.inc"
40 
41 // Find a larger type to do a load / store of a vector with.
42 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
43   unsigned StoreSize = VT.getStoreSizeInBits();
44   if (StoreSize <= 32)
45     return EVT::getIntegerVT(Ctx, StoreSize);
46 
47   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
48   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
49 }
50 
51 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
52   EVT VT = Op.getValueType();
53   KnownBits Known = DAG.computeKnownBits(Op);
54   return VT.getSizeInBits() - Known.countMinLeadingZeros();
55 }
56 
57 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
58   EVT VT = Op.getValueType();
59 
60   // In order for this to be a signed 24-bit value, bit 23, must
61   // be a sign bit.
62   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
63 }
64 
65 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
66                                            const AMDGPUSubtarget &STI)
67     : TargetLowering(TM), Subtarget(&STI) {
68   // Lower floating point store/load to integer store/load to reduce the number
69   // of patterns in tablegen.
70   setOperationAction(ISD::LOAD, MVT::f32, Promote);
71   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
72 
73   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
74   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
75 
76   setOperationAction(ISD::LOAD, MVT::v3f32, Promote);
77   AddPromotedToType(ISD::LOAD, MVT::v3f32, MVT::v3i32);
78 
79   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
80   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
81 
82   setOperationAction(ISD::LOAD, MVT::v5f32, Promote);
83   AddPromotedToType(ISD::LOAD, MVT::v5f32, MVT::v5i32);
84 
85   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
86   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
87 
88   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
89   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
90 
91   setOperationAction(ISD::LOAD, MVT::v32f32, Promote);
92   AddPromotedToType(ISD::LOAD, MVT::v32f32, MVT::v32i32);
93 
94   setOperationAction(ISD::LOAD, MVT::i64, Promote);
95   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
96 
97   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
98   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
99 
100   setOperationAction(ISD::LOAD, MVT::f64, Promote);
101   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
102 
103   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
104   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
105 
106   // There are no 64-bit extloads. These should be done as a 32-bit extload and
107   // an extension to 64-bit.
108   for (MVT VT : MVT::integer_valuetypes()) {
109     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
110     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
111     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
112   }
113 
114   for (MVT VT : MVT::integer_valuetypes()) {
115     if (VT == MVT::i64)
116       continue;
117 
118     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
119     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
120     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
121     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
122 
123     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
124     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
125     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
126     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
127 
128     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
129     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
130     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
131     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
132   }
133 
134   for (MVT VT : MVT::integer_fixedlen_vector_valuetypes()) {
135     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
136     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
137     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
138     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
139     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
140     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
141     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
142     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
143     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
144     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v3i16, Expand);
145     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v3i16, Expand);
146     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v3i16, Expand);
147     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
148     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
149     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
150   }
151 
152   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
153   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
154   setLoadExtAction(ISD::EXTLOAD, MVT::v3f32, MVT::v3f16, Expand);
155   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
156   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
157   setLoadExtAction(ISD::EXTLOAD, MVT::v16f32, MVT::v16f16, Expand);
158   setLoadExtAction(ISD::EXTLOAD, MVT::v32f32, MVT::v32f16, Expand);
159 
160   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
161   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
162   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
163   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
164 
165   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
166   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
167   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
168   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
169 
170   setOperationAction(ISD::STORE, MVT::f32, Promote);
171   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
172 
173   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
174   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
175 
176   setOperationAction(ISD::STORE, MVT::v3f32, Promote);
177   AddPromotedToType(ISD::STORE, MVT::v3f32, MVT::v3i32);
178 
179   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
180   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
181 
182   setOperationAction(ISD::STORE, MVT::v5f32, Promote);
183   AddPromotedToType(ISD::STORE, MVT::v5f32, MVT::v5i32);
184 
185   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
186   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
187 
188   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
189   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
190 
191   setOperationAction(ISD::STORE, MVT::v32f32, Promote);
192   AddPromotedToType(ISD::STORE, MVT::v32f32, MVT::v32i32);
193 
194   setOperationAction(ISD::STORE, MVT::i64, Promote);
195   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
196 
197   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
198   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
199 
200   setOperationAction(ISD::STORE, MVT::f64, Promote);
201   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
202 
203   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
204   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
205 
206   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
207   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
208   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
209   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
210 
211   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
212   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
213   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
214   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
215 
216   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
217   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
218   setTruncStoreAction(MVT::v3f32, MVT::v3f16, Expand);
219   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
220   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
221   setTruncStoreAction(MVT::v16f32, MVT::v16f16, Expand);
222   setTruncStoreAction(MVT::v32f32, MVT::v32f16, Expand);
223 
224   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
225   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
226 
227   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
228   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
229 
230   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
231   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
232 
233   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
234   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
235 
236 
237   setOperationAction(ISD::Constant, MVT::i32, Legal);
238   setOperationAction(ISD::Constant, MVT::i64, Legal);
239   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
240   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
241 
242   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
243   setOperationAction(ISD::BRIND, MVT::Other, Expand);
244 
245   // This is totally unsupported, just custom lower to produce an error.
246   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
247 
248   // Library functions.  These default to Expand, but we have instructions
249   // for them.
250   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
251   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
252   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
253   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
254   setOperationAction(ISD::FABS,   MVT::f32, Legal);
255   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
256   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
257   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
258   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
259   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
260 
261   setOperationAction(ISD::FROUND, MVT::f32, Custom);
262   setOperationAction(ISD::FROUND, MVT::f64, Custom);
263 
264   setOperationAction(ISD::FLOG, MVT::f32, Custom);
265   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
266   setOperationAction(ISD::FEXP, MVT::f32, Custom);
267 
268 
269   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
270   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
271 
272   setOperationAction(ISD::FREM, MVT::f32, Custom);
273   setOperationAction(ISD::FREM, MVT::f64, Custom);
274 
275   // Expand to fneg + fadd.
276   setOperationAction(ISD::FSUB, MVT::f64, Expand);
277 
278   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3i32, Custom);
279   setOperationAction(ISD::CONCAT_VECTORS, MVT::v3f32, Custom);
280   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
281   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
282   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5i32, Custom);
283   setOperationAction(ISD::CONCAT_VECTORS, MVT::v5f32, Custom);
284   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
285   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
286   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
287   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
288   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3f32, Custom);
289   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v3i32, Custom);
290   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
291   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
292   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5f32, Custom);
293   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v5i32, Custom);
294   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
295   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
296   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16f32, Custom);
297   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v16i32, Custom);
298   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32f32, Custom);
299   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v32i32, Custom);
300 
301   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
302   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
303   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
304 
305   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
306   for (MVT VT : ScalarIntVTs) {
307     // These should use [SU]DIVREM, so set them to expand
308     setOperationAction(ISD::SDIV, VT, Expand);
309     setOperationAction(ISD::UDIV, VT, Expand);
310     setOperationAction(ISD::SREM, VT, Expand);
311     setOperationAction(ISD::UREM, VT, Expand);
312 
313     // GPU does not have divrem function for signed or unsigned.
314     setOperationAction(ISD::SDIVREM, VT, Custom);
315     setOperationAction(ISD::UDIVREM, VT, Custom);
316 
317     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
318     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
319     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
320 
321     setOperationAction(ISD::BSWAP, VT, Expand);
322     setOperationAction(ISD::CTTZ, VT, Expand);
323     setOperationAction(ISD::CTLZ, VT, Expand);
324 
325     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
326     setOperationAction(ISD::ADDC, VT, Legal);
327     setOperationAction(ISD::SUBC, VT, Legal);
328     setOperationAction(ISD::ADDE, VT, Legal);
329     setOperationAction(ISD::SUBE, VT, Legal);
330   }
331 
332   // The hardware supports 32-bit ROTR, but not ROTL.
333   setOperationAction(ISD::ROTL, MVT::i32, Expand);
334   setOperationAction(ISD::ROTL, MVT::i64, Expand);
335   setOperationAction(ISD::ROTR, MVT::i64, Expand);
336 
337   setOperationAction(ISD::MUL, MVT::i64, Expand);
338   setOperationAction(ISD::MULHU, MVT::i64, Expand);
339   setOperationAction(ISD::MULHS, MVT::i64, Expand);
340   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
341   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
342   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
343   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
344   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
345 
346   setOperationAction(ISD::SMIN, MVT::i32, Legal);
347   setOperationAction(ISD::UMIN, MVT::i32, Legal);
348   setOperationAction(ISD::SMAX, MVT::i32, Legal);
349   setOperationAction(ISD::UMAX, MVT::i32, Legal);
350 
351   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
352   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
353   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
354   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
355 
356   static const MVT::SimpleValueType VectorIntTypes[] = {
357     MVT::v2i32, MVT::v3i32, MVT::v4i32, MVT::v5i32
358   };
359 
360   for (MVT VT : VectorIntTypes) {
361     // Expand the following operations for the current type by default.
362     setOperationAction(ISD::ADD,  VT, Expand);
363     setOperationAction(ISD::AND,  VT, Expand);
364     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
365     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
366     setOperationAction(ISD::MUL,  VT, Expand);
367     setOperationAction(ISD::MULHU, VT, Expand);
368     setOperationAction(ISD::MULHS, VT, Expand);
369     setOperationAction(ISD::OR,   VT, Expand);
370     setOperationAction(ISD::SHL,  VT, Expand);
371     setOperationAction(ISD::SRA,  VT, Expand);
372     setOperationAction(ISD::SRL,  VT, Expand);
373     setOperationAction(ISD::ROTL, VT, Expand);
374     setOperationAction(ISD::ROTR, VT, Expand);
375     setOperationAction(ISD::SUB,  VT, Expand);
376     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
377     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
378     setOperationAction(ISD::SDIV, VT, Expand);
379     setOperationAction(ISD::UDIV, VT, Expand);
380     setOperationAction(ISD::SREM, VT, Expand);
381     setOperationAction(ISD::UREM, VT, Expand);
382     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
383     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
384     setOperationAction(ISD::SDIVREM, VT, Custom);
385     setOperationAction(ISD::UDIVREM, VT, Expand);
386     setOperationAction(ISD::SELECT, VT, Expand);
387     setOperationAction(ISD::VSELECT, VT, Expand);
388     setOperationAction(ISD::SELECT_CC, VT, Expand);
389     setOperationAction(ISD::XOR,  VT, Expand);
390     setOperationAction(ISD::BSWAP, VT, Expand);
391     setOperationAction(ISD::CTPOP, VT, Expand);
392     setOperationAction(ISD::CTTZ, VT, Expand);
393     setOperationAction(ISD::CTLZ, VT, Expand);
394     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
395     setOperationAction(ISD::SETCC, VT, Expand);
396   }
397 
398   static const MVT::SimpleValueType FloatVectorTypes[] = {
399      MVT::v2f32, MVT::v3f32, MVT::v4f32, MVT::v5f32
400   };
401 
402   for (MVT VT : FloatVectorTypes) {
403     setOperationAction(ISD::FABS, VT, Expand);
404     setOperationAction(ISD::FMINNUM, VT, Expand);
405     setOperationAction(ISD::FMAXNUM, VT, Expand);
406     setOperationAction(ISD::FADD, VT, Expand);
407     setOperationAction(ISD::FCEIL, VT, Expand);
408     setOperationAction(ISD::FCOS, VT, Expand);
409     setOperationAction(ISD::FDIV, VT, Expand);
410     setOperationAction(ISD::FEXP2, VT, Expand);
411     setOperationAction(ISD::FEXP, VT, Expand);
412     setOperationAction(ISD::FLOG2, VT, Expand);
413     setOperationAction(ISD::FREM, VT, Expand);
414     setOperationAction(ISD::FLOG, VT, Expand);
415     setOperationAction(ISD::FLOG10, VT, Expand);
416     setOperationAction(ISD::FPOW, VT, Expand);
417     setOperationAction(ISD::FFLOOR, VT, Expand);
418     setOperationAction(ISD::FTRUNC, VT, Expand);
419     setOperationAction(ISD::FMUL, VT, Expand);
420     setOperationAction(ISD::FMA, VT, Expand);
421     setOperationAction(ISD::FRINT, VT, Expand);
422     setOperationAction(ISD::FNEARBYINT, VT, Expand);
423     setOperationAction(ISD::FSQRT, VT, Expand);
424     setOperationAction(ISD::FSIN, VT, Expand);
425     setOperationAction(ISD::FSUB, VT, Expand);
426     setOperationAction(ISD::FNEG, VT, Expand);
427     setOperationAction(ISD::VSELECT, VT, Expand);
428     setOperationAction(ISD::SELECT_CC, VT, Expand);
429     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
430     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
431     setOperationAction(ISD::SETCC, VT, Expand);
432     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
433   }
434 
435   // This causes using an unrolled select operation rather than expansion with
436   // bit operations. This is in general better, but the alternative using BFI
437   // instructions may be better if the select sources are SGPRs.
438   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
439   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
440 
441   setOperationAction(ISD::SELECT, MVT::v3f32, Promote);
442   AddPromotedToType(ISD::SELECT, MVT::v3f32, MVT::v3i32);
443 
444   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
445   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
446 
447   setOperationAction(ISD::SELECT, MVT::v5f32, Promote);
448   AddPromotedToType(ISD::SELECT, MVT::v5f32, MVT::v5i32);
449 
450   // There are no libcalls of any kind.
451   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
452     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
453 
454   setSchedulingPreference(Sched::RegPressure);
455   setJumpIsExpensive(true);
456 
457   // FIXME: This is only partially true. If we have to do vector compares, any
458   // SGPR pair can be a condition register. If we have a uniform condition, we
459   // are better off doing SALU operations, where there is only one SCC. For now,
460   // we don't have a way of knowing during instruction selection if a condition
461   // will be uniform and we always use vector compares. Assume we are using
462   // vector compares until that is fixed.
463   setHasMultipleConditionRegisters(true);
464 
465   setMinCmpXchgSizeInBits(32);
466   setSupportsUnalignedAtomics(false);
467 
468   PredictableSelectIsExpensive = false;
469 
470   // We want to find all load dependencies for long chains of stores to enable
471   // merging into very wide vectors. The problem is with vectors with > 4
472   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
473   // vectors are a legal type, even though we have to split the loads
474   // usually. When we can more precisely specify load legality per address
475   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
476   // smarter so that they can figure out what to do in 2 iterations without all
477   // N > 4 stores on the same chain.
478   GatherAllAliasesMaxDepth = 16;
479 
480   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
481   // about these during lowering.
482   MaxStoresPerMemcpy  = 0xffffffff;
483   MaxStoresPerMemmove = 0xffffffff;
484   MaxStoresPerMemset  = 0xffffffff;
485 
486   setTargetDAGCombine(ISD::BITCAST);
487   setTargetDAGCombine(ISD::SHL);
488   setTargetDAGCombine(ISD::SRA);
489   setTargetDAGCombine(ISD::SRL);
490   setTargetDAGCombine(ISD::TRUNCATE);
491   setTargetDAGCombine(ISD::MUL);
492   setTargetDAGCombine(ISD::MULHU);
493   setTargetDAGCombine(ISD::MULHS);
494   setTargetDAGCombine(ISD::SELECT);
495   setTargetDAGCombine(ISD::SELECT_CC);
496   setTargetDAGCombine(ISD::STORE);
497   setTargetDAGCombine(ISD::FADD);
498   setTargetDAGCombine(ISD::FSUB);
499   setTargetDAGCombine(ISD::FNEG);
500   setTargetDAGCombine(ISD::FABS);
501   setTargetDAGCombine(ISD::AssertZext);
502   setTargetDAGCombine(ISD::AssertSext);
503   setTargetDAGCombine(ISD::INTRINSIC_WO_CHAIN);
504 }
505 
506 //===----------------------------------------------------------------------===//
507 // Target Information
508 //===----------------------------------------------------------------------===//
509 
510 LLVM_READNONE
511 static bool fnegFoldsIntoOp(unsigned Opc) {
512   switch (Opc) {
513   case ISD::FADD:
514   case ISD::FSUB:
515   case ISD::FMUL:
516   case ISD::FMA:
517   case ISD::FMAD:
518   case ISD::FMINNUM:
519   case ISD::FMAXNUM:
520   case ISD::FMINNUM_IEEE:
521   case ISD::FMAXNUM_IEEE:
522   case ISD::FSIN:
523   case ISD::FTRUNC:
524   case ISD::FRINT:
525   case ISD::FNEARBYINT:
526   case ISD::FCANONICALIZE:
527   case AMDGPUISD::RCP:
528   case AMDGPUISD::RCP_LEGACY:
529   case AMDGPUISD::RCP_IFLAG:
530   case AMDGPUISD::SIN_HW:
531   case AMDGPUISD::FMUL_LEGACY:
532   case AMDGPUISD::FMIN_LEGACY:
533   case AMDGPUISD::FMAX_LEGACY:
534   case AMDGPUISD::FMED3:
535     return true;
536   default:
537     return false;
538   }
539 }
540 
541 /// \p returns true if the operation will definitely need to use a 64-bit
542 /// encoding, and thus will use a VOP3 encoding regardless of the source
543 /// modifiers.
544 LLVM_READONLY
545 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
546   return N->getNumOperands() > 2 || VT == MVT::f64;
547 }
548 
549 // Most FP instructions support source modifiers, but this could be refined
550 // slightly.
551 LLVM_READONLY
552 static bool hasSourceMods(const SDNode *N) {
553   if (isa<MemSDNode>(N))
554     return false;
555 
556   switch (N->getOpcode()) {
557   case ISD::CopyToReg:
558   case ISD::SELECT:
559   case ISD::FDIV:
560   case ISD::FREM:
561   case ISD::INLINEASM:
562   case ISD::INLINEASM_BR:
563   case AMDGPUISD::DIV_SCALE:
564   case ISD::INTRINSIC_W_CHAIN:
565 
566   // TODO: Should really be looking at the users of the bitcast. These are
567   // problematic because bitcasts are used to legalize all stores to integer
568   // types.
569   case ISD::BITCAST:
570     return false;
571   case ISD::INTRINSIC_WO_CHAIN: {
572     switch (cast<ConstantSDNode>(N->getOperand(0))->getZExtValue()) {
573     case Intrinsic::amdgcn_interp_p1:
574     case Intrinsic::amdgcn_interp_p2:
575     case Intrinsic::amdgcn_interp_mov:
576     case Intrinsic::amdgcn_interp_p1_f16:
577     case Intrinsic::amdgcn_interp_p2_f16:
578       return false;
579     default:
580       return true;
581     }
582   }
583   default:
584     return true;
585   }
586 }
587 
588 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
589                                                  unsigned CostThreshold) {
590   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
591   // it is truly free to use a source modifier in all cases. If there are
592   // multiple users but for each one will necessitate using VOP3, there will be
593   // a code size increase. Try to avoid increasing code size unless we know it
594   // will save on the instruction count.
595   unsigned NumMayIncreaseSize = 0;
596   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
597 
598   // XXX - Should this limit number of uses to check?
599   for (const SDNode *U : N->uses()) {
600     if (!hasSourceMods(U))
601       return false;
602 
603     if (!opMustUseVOP3Encoding(U, VT)) {
604       if (++NumMayIncreaseSize > CostThreshold)
605         return false;
606     }
607   }
608 
609   return true;
610 }
611 
612 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
613   return MVT::i32;
614 }
615 
616 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
617   return true;
618 }
619 
620 // The backend supports 32 and 64 bit floating point immediates.
621 // FIXME: Why are we reporting vectors of FP immediates as legal?
622 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT,
623                                         bool ForCodeSize) const {
624   EVT ScalarVT = VT.getScalarType();
625   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
626          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
627 }
628 
629 // We don't want to shrink f64 / f32 constants.
630 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
631   EVT ScalarVT = VT.getScalarType();
632   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
633 }
634 
635 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
636                                                  ISD::LoadExtType ExtTy,
637                                                  EVT NewVT) const {
638   // TODO: This may be worth removing. Check regression tests for diffs.
639   if (!TargetLoweringBase::shouldReduceLoadWidth(N, ExtTy, NewVT))
640     return false;
641 
642   unsigned NewSize = NewVT.getStoreSizeInBits();
643 
644   // If we are reducing to a 32-bit load, this is always better.
645   if (NewSize == 32)
646     return true;
647 
648   EVT OldVT = N->getValueType(0);
649   unsigned OldSize = OldVT.getStoreSizeInBits();
650 
651   MemSDNode *MN = cast<MemSDNode>(N);
652   unsigned AS = MN->getAddressSpace();
653   // Do not shrink an aligned scalar load to sub-dword.
654   // Scalar engine cannot do sub-dword loads.
655   if (OldSize >= 32 && NewSize < 32 && MN->getAlignment() >= 4 &&
656       (AS == AMDGPUAS::CONSTANT_ADDRESS ||
657        AS == AMDGPUAS::CONSTANT_ADDRESS_32BIT ||
658        (isa<LoadSDNode>(N) &&
659         AS == AMDGPUAS::GLOBAL_ADDRESS && MN->isInvariant())) &&
660       AMDGPUInstrInfo::isUniformMMO(MN->getMemOperand()))
661     return false;
662 
663   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
664   // extloads, so doing one requires using a buffer_load. In cases where we
665   // still couldn't use a scalar load, using the wider load shouldn't really
666   // hurt anything.
667 
668   // If the old size already had to be an extload, there's no harm in continuing
669   // to reduce the width.
670   return (OldSize < 32);
671 }
672 
673 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy, EVT CastTy,
674                                                    const SelectionDAG &DAG,
675                                                    const MachineMemOperand &MMO) const {
676 
677   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
678 
679   if (LoadTy.getScalarType() == MVT::i32)
680     return false;
681 
682   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
683   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
684 
685   if ((LScalarSize >= CastScalarSize) && (CastScalarSize < 32))
686     return false;
687 
688   bool Fast = false;
689   return allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
690                                         CastTy, MMO, &Fast) &&
691          Fast;
692 }
693 
694 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
695 // profitable with the expansion for 64-bit since it's generally good to
696 // speculate things.
697 // FIXME: These should really have the size as a parameter.
698 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
699   return true;
700 }
701 
702 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
703   return true;
704 }
705 
706 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
707   switch (N->getOpcode()) {
708     default:
709     return false;
710     case ISD::EntryToken:
711     case ISD::TokenFactor:
712       return true;
713     case ISD::INTRINSIC_WO_CHAIN:
714     {
715       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
716       switch (IntrID) {
717         default:
718         return false;
719         case Intrinsic::amdgcn_readfirstlane:
720         case Intrinsic::amdgcn_readlane:
721           return true;
722       }
723     }
724     break;
725     case ISD::LOAD:
726     {
727       if (cast<LoadSDNode>(N)->getMemOperand()->getAddrSpace() ==
728           AMDGPUAS::CONSTANT_ADDRESS_32BIT)
729         return true;
730       return false;
731     }
732     break;
733   }
734 }
735 
736 //===---------------------------------------------------------------------===//
737 // Target Properties
738 //===---------------------------------------------------------------------===//
739 
740 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
741   assert(VT.isFloatingPoint());
742 
743   // Packed operations do not have a fabs modifier.
744   return VT == MVT::f32 || VT == MVT::f64 ||
745          (Subtarget->has16BitInsts() && VT == MVT::f16);
746 }
747 
748 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
749   assert(VT.isFloatingPoint());
750   return VT == MVT::f32 || VT == MVT::f64 ||
751          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
752          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
753 }
754 
755 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
756                                                          unsigned NumElem,
757                                                          unsigned AS) const {
758   return true;
759 }
760 
761 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
762   // There are few operations which truly have vector input operands. Any vector
763   // operation is going to involve operations on each component, and a
764   // build_vector will be a copy per element, so it always makes sense to use a
765   // build_vector input in place of the extracted element to avoid a copy into a
766   // super register.
767   //
768   // We should probably only do this if all users are extracts only, but this
769   // should be the common case.
770   return true;
771 }
772 
773 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
774   // Truncate is just accessing a subregister.
775 
776   unsigned SrcSize = Source.getSizeInBits();
777   unsigned DestSize = Dest.getSizeInBits();
778 
779   return DestSize < SrcSize && DestSize % 32 == 0 ;
780 }
781 
782 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
783   // Truncate is just accessing a subregister.
784 
785   unsigned SrcSize = Source->getScalarSizeInBits();
786   unsigned DestSize = Dest->getScalarSizeInBits();
787 
788   if (DestSize== 16 && Subtarget->has16BitInsts())
789     return SrcSize >= 32;
790 
791   return DestSize < SrcSize && DestSize % 32 == 0;
792 }
793 
794 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
795   unsigned SrcSize = Src->getScalarSizeInBits();
796   unsigned DestSize = Dest->getScalarSizeInBits();
797 
798   if (SrcSize == 16 && Subtarget->has16BitInsts())
799     return DestSize >= 32;
800 
801   return SrcSize == 32 && DestSize == 64;
802 }
803 
804 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
805   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
806   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
807   // this will enable reducing 64-bit operations the 32-bit, which is always
808   // good.
809 
810   if (Src == MVT::i16)
811     return Dest == MVT::i32 ||Dest == MVT::i64 ;
812 
813   return Src == MVT::i32 && Dest == MVT::i64;
814 }
815 
816 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
817   return isZExtFree(Val.getValueType(), VT2);
818 }
819 
820 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
821   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
822   // limited number of native 64-bit operations. Shrinking an operation to fit
823   // in a single 32-bit register should always be helpful. As currently used,
824   // this is much less general than the name suggests, and is only used in
825   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
826   // not profitable, and may actually be harmful.
827   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
828 }
829 
830 //===---------------------------------------------------------------------===//
831 // TargetLowering Callbacks
832 //===---------------------------------------------------------------------===//
833 
834 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
835                                                   bool IsVarArg) {
836   switch (CC) {
837   case CallingConv::AMDGPU_VS:
838   case CallingConv::AMDGPU_GS:
839   case CallingConv::AMDGPU_PS:
840   case CallingConv::AMDGPU_CS:
841   case CallingConv::AMDGPU_HS:
842   case CallingConv::AMDGPU_ES:
843   case CallingConv::AMDGPU_LS:
844     return CC_AMDGPU;
845   case CallingConv::C:
846   case CallingConv::Fast:
847   case CallingConv::Cold:
848     return CC_AMDGPU_Func;
849   case CallingConv::AMDGPU_KERNEL:
850   case CallingConv::SPIR_KERNEL:
851   default:
852     report_fatal_error("Unsupported calling convention for call");
853   }
854 }
855 
856 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
857                                                     bool IsVarArg) {
858   switch (CC) {
859   case CallingConv::AMDGPU_KERNEL:
860   case CallingConv::SPIR_KERNEL:
861     llvm_unreachable("kernels should not be handled here");
862   case CallingConv::AMDGPU_VS:
863   case CallingConv::AMDGPU_GS:
864   case CallingConv::AMDGPU_PS:
865   case CallingConv::AMDGPU_CS:
866   case CallingConv::AMDGPU_HS:
867   case CallingConv::AMDGPU_ES:
868   case CallingConv::AMDGPU_LS:
869     return RetCC_SI_Shader;
870   case CallingConv::C:
871   case CallingConv::Fast:
872   case CallingConv::Cold:
873     return RetCC_AMDGPU_Func;
874   default:
875     report_fatal_error("Unsupported calling convention.");
876   }
877 }
878 
879 /// The SelectionDAGBuilder will automatically promote function arguments
880 /// with illegal types.  However, this does not work for the AMDGPU targets
881 /// since the function arguments are stored in memory as these illegal types.
882 /// In order to handle this properly we need to get the original types sizes
883 /// from the LLVM IR Function and fixup the ISD:InputArg values before
884 /// passing them to AnalyzeFormalArguments()
885 
886 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
887 /// input values across multiple registers.  Each item in the Ins array
888 /// represents a single value that will be stored in registers.  Ins[x].VT is
889 /// the value type of the value that will be stored in the register, so
890 /// whatever SDNode we lower the argument to needs to be this type.
891 ///
892 /// In order to correctly lower the arguments we need to know the size of each
893 /// argument.  Since Ins[x].VT gives us the size of the register that will
894 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
895 /// for the orignal function argument so that we can deduce the correct memory
896 /// type to use for Ins[x].  In most cases the correct memory type will be
897 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
898 /// we have a kernel argument of type v8i8, this argument will be split into
899 /// 8 parts and each part will be represented by its own item in the Ins array.
900 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
901 /// the argument before it was split.  From this, we deduce that the memory type
902 /// for each individual part is i8.  We pass the memory type as LocVT to the
903 /// calling convention analysis function and the register type (Ins[x].VT) as
904 /// the ValVT.
905 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
906   CCState &State,
907   const SmallVectorImpl<ISD::InputArg> &Ins) const {
908   const MachineFunction &MF = State.getMachineFunction();
909   const Function &Fn = MF.getFunction();
910   LLVMContext &Ctx = Fn.getParent()->getContext();
911   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
912   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
913   CallingConv::ID CC = Fn.getCallingConv();
914 
915   unsigned MaxAlign = 1;
916   uint64_t ExplicitArgOffset = 0;
917   const DataLayout &DL = Fn.getParent()->getDataLayout();
918 
919   unsigned InIndex = 0;
920 
921   for (const Argument &Arg : Fn.args()) {
922     Type *BaseArgTy = Arg.getType();
923     unsigned Align = DL.getABITypeAlignment(BaseArgTy);
924     MaxAlign = std::max(Align, MaxAlign);
925     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
926 
927     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Align) + ExplicitOffset;
928     ExplicitArgOffset = alignTo(ExplicitArgOffset, Align) + AllocSize;
929 
930     // We're basically throwing away everything passed into us and starting over
931     // to get accurate in-memory offsets. The "PartOffset" is completely useless
932     // to us as computed in Ins.
933     //
934     // We also need to figure out what type legalization is trying to do to get
935     // the correct memory offsets.
936 
937     SmallVector<EVT, 16> ValueVTs;
938     SmallVector<uint64_t, 16> Offsets;
939     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
940 
941     for (unsigned Value = 0, NumValues = ValueVTs.size();
942          Value != NumValues; ++Value) {
943       uint64_t BasePartOffset = Offsets[Value];
944 
945       EVT ArgVT = ValueVTs[Value];
946       EVT MemVT = ArgVT;
947       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
948       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
949 
950       if (NumRegs == 1) {
951         // This argument is not split, so the IR type is the memory type.
952         if (ArgVT.isExtended()) {
953           // We have an extended type, like i24, so we should just use the
954           // register type.
955           MemVT = RegisterVT;
956         } else {
957           MemVT = ArgVT;
958         }
959       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
960                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
961         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
962         // We have a vector value which has been split into a vector with
963         // the same scalar type, but fewer elements.  This should handle
964         // all the floating-point vector types.
965         MemVT = RegisterVT;
966       } else if (ArgVT.isVector() &&
967                  ArgVT.getVectorNumElements() == NumRegs) {
968         // This arg has been split so that each element is stored in a separate
969         // register.
970         MemVT = ArgVT.getScalarType();
971       } else if (ArgVT.isExtended()) {
972         // We have an extended type, like i65.
973         MemVT = RegisterVT;
974       } else {
975         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
976         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
977         if (RegisterVT.isInteger()) {
978           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
979         } else if (RegisterVT.isVector()) {
980           assert(!RegisterVT.getScalarType().isFloatingPoint());
981           unsigned NumElements = RegisterVT.getVectorNumElements();
982           assert(MemoryBits % NumElements == 0);
983           // This vector type has been split into another vector type with
984           // a different elements size.
985           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
986                                            MemoryBits / NumElements);
987           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
988         } else {
989           llvm_unreachable("cannot deduce memory type.");
990         }
991       }
992 
993       // Convert one element vectors to scalar.
994       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
995         MemVT = MemVT.getScalarType();
996 
997       // Round up vec3/vec5 argument.
998       if (MemVT.isVector() && !MemVT.isPow2VectorType()) {
999         assert(MemVT.getVectorNumElements() == 3 ||
1000                MemVT.getVectorNumElements() == 5);
1001         MemVT = MemVT.getPow2VectorType(State.getContext());
1002       }
1003 
1004       unsigned PartOffset = 0;
1005       for (unsigned i = 0; i != NumRegs; ++i) {
1006         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1007                                                BasePartOffset + PartOffset,
1008                                                MemVT.getSimpleVT(),
1009                                                CCValAssign::Full));
1010         PartOffset += MemVT.getStoreSize();
1011       }
1012     }
1013   }
1014 }
1015 
1016 SDValue AMDGPUTargetLowering::LowerReturn(
1017   SDValue Chain, CallingConv::ID CallConv,
1018   bool isVarArg,
1019   const SmallVectorImpl<ISD::OutputArg> &Outs,
1020   const SmallVectorImpl<SDValue> &OutVals,
1021   const SDLoc &DL, SelectionDAG &DAG) const {
1022   // FIXME: Fails for r600 tests
1023   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1024   // "wave terminate should not have return values");
1025   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1026 }
1027 
1028 //===---------------------------------------------------------------------===//
1029 // Target specific lowering
1030 //===---------------------------------------------------------------------===//
1031 
1032 /// Selects the correct CCAssignFn for a given CallingConvention value.
1033 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1034                                                     bool IsVarArg) {
1035   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1036 }
1037 
1038 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1039                                                       bool IsVarArg) {
1040   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1041 }
1042 
1043 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1044                                                   SelectionDAG &DAG,
1045                                                   MachineFrameInfo &MFI,
1046                                                   int ClobberedFI) const {
1047   SmallVector<SDValue, 8> ArgChains;
1048   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1049   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1050 
1051   // Include the original chain at the beginning of the list. When this is
1052   // used by target LowerCall hooks, this helps legalize find the
1053   // CALLSEQ_BEGIN node.
1054   ArgChains.push_back(Chain);
1055 
1056   // Add a chain value for each stack argument corresponding
1057   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1058                             UE = DAG.getEntryNode().getNode()->use_end();
1059        U != UE; ++U) {
1060     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1061       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1062         if (FI->getIndex() < 0) {
1063           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1064           int64_t InLastByte = InFirstByte;
1065           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1066 
1067           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1068               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1069             ArgChains.push_back(SDValue(L, 1));
1070         }
1071       }
1072     }
1073   }
1074 
1075   // Build a tokenfactor for all the chains.
1076   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1077 }
1078 
1079 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1080                                                  SmallVectorImpl<SDValue> &InVals,
1081                                                  StringRef Reason) const {
1082   SDValue Callee = CLI.Callee;
1083   SelectionDAG &DAG = CLI.DAG;
1084 
1085   const Function &Fn = DAG.getMachineFunction().getFunction();
1086 
1087   StringRef FuncName("<unknown>");
1088 
1089   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1090     FuncName = G->getSymbol();
1091   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1092     FuncName = G->getGlobal()->getName();
1093 
1094   DiagnosticInfoUnsupported NoCalls(
1095     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1096   DAG.getContext()->diagnose(NoCalls);
1097 
1098   if (!CLI.IsTailCall) {
1099     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1100       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1101   }
1102 
1103   return DAG.getEntryNode();
1104 }
1105 
1106 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1107                                         SmallVectorImpl<SDValue> &InVals) const {
1108   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1109 }
1110 
1111 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1112                                                       SelectionDAG &DAG) const {
1113   const Function &Fn = DAG.getMachineFunction().getFunction();
1114 
1115   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1116                                             SDLoc(Op).getDebugLoc());
1117   DAG.getContext()->diagnose(NoDynamicAlloca);
1118   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1119   return DAG.getMergeValues(Ops, SDLoc());
1120 }
1121 
1122 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1123                                              SelectionDAG &DAG) const {
1124   switch (Op.getOpcode()) {
1125   default:
1126     Op->print(errs(), &DAG);
1127     llvm_unreachable("Custom lowering code for this"
1128                      "instruction is not implemented yet!");
1129     break;
1130   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1131   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1132   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1133   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1134   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1135   case ISD::FREM: return LowerFREM(Op, DAG);
1136   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1137   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1138   case ISD::FRINT: return LowerFRINT(Op, DAG);
1139   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1140   case ISD::FROUND: return LowerFROUND(Op, DAG);
1141   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1142   case ISD::FLOG:
1143     return LowerFLOG(Op, DAG, 1.0F / numbers::log2ef);
1144   case ISD::FLOG10:
1145     return LowerFLOG(Op, DAG, numbers::ln2f / numbers::ln10f);
1146   case ISD::FEXP:
1147     return lowerFEXP(Op, DAG);
1148   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1149   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1150   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1151   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1152   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1153   case ISD::CTTZ:
1154   case ISD::CTTZ_ZERO_UNDEF:
1155   case ISD::CTLZ:
1156   case ISD::CTLZ_ZERO_UNDEF:
1157     return LowerCTLZ_CTTZ(Op, DAG);
1158   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1159   }
1160   return Op;
1161 }
1162 
1163 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1164                                               SmallVectorImpl<SDValue> &Results,
1165                                               SelectionDAG &DAG) const {
1166   switch (N->getOpcode()) {
1167   case ISD::SIGN_EXTEND_INREG:
1168     // Different parts of legalization seem to interpret which type of
1169     // sign_extend_inreg is the one to check for custom lowering. The extended
1170     // from type is what really matters, but some places check for custom
1171     // lowering of the result type. This results in trying to use
1172     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1173     // nothing here and let the illegal result integer be handled normally.
1174     return;
1175   default:
1176     return;
1177   }
1178 }
1179 
1180 bool AMDGPUTargetLowering::hasDefinedInitializer(const GlobalValue *GV) {
1181   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1182   if (!GVar || !GVar->hasInitializer())
1183     return false;
1184 
1185   return !isa<UndefValue>(GVar->getInitializer());
1186 }
1187 
1188 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1189                                                  SDValue Op,
1190                                                  SelectionDAG &DAG) const {
1191 
1192   const DataLayout &DL = DAG.getDataLayout();
1193   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1194   const GlobalValue *GV = G->getGlobal();
1195 
1196   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1197       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1198     if (!MFI->isEntryFunction()) {
1199       const Function &Fn = DAG.getMachineFunction().getFunction();
1200       DiagnosticInfoUnsupported BadLDSDecl(
1201         Fn, "local memory global used by non-kernel function", SDLoc(Op).getDebugLoc());
1202       DAG.getContext()->diagnose(BadLDSDecl);
1203     }
1204 
1205     // XXX: What does the value of G->getOffset() mean?
1206     assert(G->getOffset() == 0 &&
1207          "Do not know what to do with an non-zero offset");
1208 
1209     // TODO: We could emit code to handle the initialization somewhere.
1210     if (!hasDefinedInitializer(GV)) {
1211       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1212       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1213     }
1214   }
1215 
1216   const Function &Fn = DAG.getMachineFunction().getFunction();
1217   DiagnosticInfoUnsupported BadInit(
1218       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1219   DAG.getContext()->diagnose(BadInit);
1220   return SDValue();
1221 }
1222 
1223 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1224                                                   SelectionDAG &DAG) const {
1225   SmallVector<SDValue, 8> Args;
1226 
1227   EVT VT = Op.getValueType();
1228   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1229     SDLoc SL(Op);
1230     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1231     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1232 
1233     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1234     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1235   }
1236 
1237   for (const SDUse &U : Op->ops())
1238     DAG.ExtractVectorElements(U.get(), Args);
1239 
1240   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1241 }
1242 
1243 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1244                                                      SelectionDAG &DAG) const {
1245 
1246   SmallVector<SDValue, 8> Args;
1247   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1248   EVT VT = Op.getValueType();
1249   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1250                             VT.getVectorNumElements());
1251 
1252   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1253 }
1254 
1255 /// Generate Min/Max node
1256 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1257                                                    SDValue LHS, SDValue RHS,
1258                                                    SDValue True, SDValue False,
1259                                                    SDValue CC,
1260                                                    DAGCombinerInfo &DCI) const {
1261   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1262     return SDValue();
1263 
1264   SelectionDAG &DAG = DCI.DAG;
1265   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1266   switch (CCOpcode) {
1267   case ISD::SETOEQ:
1268   case ISD::SETONE:
1269   case ISD::SETUNE:
1270   case ISD::SETNE:
1271   case ISD::SETUEQ:
1272   case ISD::SETEQ:
1273   case ISD::SETFALSE:
1274   case ISD::SETFALSE2:
1275   case ISD::SETTRUE:
1276   case ISD::SETTRUE2:
1277   case ISD::SETUO:
1278   case ISD::SETO:
1279     break;
1280   case ISD::SETULE:
1281   case ISD::SETULT: {
1282     if (LHS == True)
1283       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1284     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1285   }
1286   case ISD::SETOLE:
1287   case ISD::SETOLT:
1288   case ISD::SETLE:
1289   case ISD::SETLT: {
1290     // Ordered. Assume ordered for undefined.
1291 
1292     // Only do this after legalization to avoid interfering with other combines
1293     // which might occur.
1294     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1295         !DCI.isCalledByLegalizer())
1296       return SDValue();
1297 
1298     // We need to permute the operands to get the correct NaN behavior. The
1299     // selected operand is the second one based on the failing compare with NaN,
1300     // so permute it based on the compare type the hardware uses.
1301     if (LHS == True)
1302       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1303     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1304   }
1305   case ISD::SETUGE:
1306   case ISD::SETUGT: {
1307     if (LHS == True)
1308       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1309     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1310   }
1311   case ISD::SETGT:
1312   case ISD::SETGE:
1313   case ISD::SETOGE:
1314   case ISD::SETOGT: {
1315     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1316         !DCI.isCalledByLegalizer())
1317       return SDValue();
1318 
1319     if (LHS == True)
1320       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1321     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1322   }
1323   case ISD::SETCC_INVALID:
1324     llvm_unreachable("Invalid setcc condcode!");
1325   }
1326   return SDValue();
1327 }
1328 
1329 std::pair<SDValue, SDValue>
1330 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1331   SDLoc SL(Op);
1332 
1333   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1334 
1335   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1336   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1337 
1338   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1339   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1340 
1341   return std::make_pair(Lo, Hi);
1342 }
1343 
1344 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1345   SDLoc SL(Op);
1346 
1347   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1348   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1349   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1350 }
1351 
1352 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1353   SDLoc SL(Op);
1354 
1355   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1356   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1357   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1358 }
1359 
1360 // Split a vector type into two parts. The first part is a power of two vector.
1361 // The second part is whatever is left over, and is a scalar if it would
1362 // otherwise be a 1-vector.
1363 std::pair<EVT, EVT>
1364 AMDGPUTargetLowering::getSplitDestVTs(const EVT &VT, SelectionDAG &DAG) const {
1365   EVT LoVT, HiVT;
1366   EVT EltVT = VT.getVectorElementType();
1367   unsigned NumElts = VT.getVectorNumElements();
1368   unsigned LoNumElts = PowerOf2Ceil((NumElts + 1) / 2);
1369   LoVT = EVT::getVectorVT(*DAG.getContext(), EltVT, LoNumElts);
1370   HiVT = NumElts - LoNumElts == 1
1371              ? EltVT
1372              : EVT::getVectorVT(*DAG.getContext(), EltVT, NumElts - LoNumElts);
1373   return std::make_pair(LoVT, HiVT);
1374 }
1375 
1376 // Split a vector value into two parts of types LoVT and HiVT. HiVT could be
1377 // scalar.
1378 std::pair<SDValue, SDValue>
1379 AMDGPUTargetLowering::splitVector(const SDValue &N, const SDLoc &DL,
1380                                   const EVT &LoVT, const EVT &HiVT,
1381                                   SelectionDAG &DAG) const {
1382   assert(LoVT.getVectorNumElements() +
1383                  (HiVT.isVector() ? HiVT.getVectorNumElements() : 1) <=
1384              N.getValueType().getVectorNumElements() &&
1385          "More vector elements requested than available!");
1386   auto IdxTy = getVectorIdxTy(DAG.getDataLayout());
1387   SDValue Lo = DAG.getNode(ISD::EXTRACT_SUBVECTOR, DL, LoVT, N,
1388                            DAG.getConstant(0, DL, IdxTy));
1389   SDValue Hi = DAG.getNode(
1390       HiVT.isVector() ? ISD::EXTRACT_SUBVECTOR : ISD::EXTRACT_VECTOR_ELT, DL,
1391       HiVT, N, DAG.getConstant(LoVT.getVectorNumElements(), DL, IdxTy));
1392   return std::make_pair(Lo, Hi);
1393 }
1394 
1395 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1396                                               SelectionDAG &DAG) const {
1397   LoadSDNode *Load = cast<LoadSDNode>(Op);
1398   EVT VT = Op.getValueType();
1399   SDLoc SL(Op);
1400 
1401 
1402   // If this is a 2 element vector, we really want to scalarize and not create
1403   // weird 1 element vectors.
1404   if (VT.getVectorNumElements() == 2) {
1405     SDValue Ops[2];
1406     std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(Load, DAG);
1407     return DAG.getMergeValues(Ops, SL);
1408   }
1409 
1410   SDValue BasePtr = Load->getBasePtr();
1411   EVT MemVT = Load->getMemoryVT();
1412 
1413   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1414 
1415   EVT LoVT, HiVT;
1416   EVT LoMemVT, HiMemVT;
1417   SDValue Lo, Hi;
1418 
1419   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1420   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1421   std::tie(Lo, Hi) = splitVector(Op, SL, LoVT, HiVT, DAG);
1422 
1423   unsigned Size = LoMemVT.getStoreSize();
1424   unsigned BaseAlign = Load->getAlignment();
1425   unsigned HiAlign = MinAlign(BaseAlign, Size);
1426 
1427   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1428                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1429                                   BaseAlign, Load->getMemOperand()->getFlags());
1430   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1431   SDValue HiLoad =
1432       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1433                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1434                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1435 
1436   auto IdxTy = getVectorIdxTy(DAG.getDataLayout());
1437   SDValue Join;
1438   if (LoVT == HiVT) {
1439     // This is the case that the vector is power of two so was evenly split.
1440     Join = DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad);
1441   } else {
1442     Join = DAG.getNode(ISD::INSERT_SUBVECTOR, SL, VT, DAG.getUNDEF(VT), LoLoad,
1443                        DAG.getConstant(0, SL, IdxTy));
1444     Join = DAG.getNode(HiVT.isVector() ? ISD::INSERT_SUBVECTOR
1445                                        : ISD::INSERT_VECTOR_ELT,
1446                        SL, VT, Join, HiLoad,
1447                        DAG.getConstant(LoVT.getVectorNumElements(), SL, IdxTy));
1448   }
1449 
1450   SDValue Ops[] = {Join, DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1451                                      LoLoad.getValue(1), HiLoad.getValue(1))};
1452 
1453   return DAG.getMergeValues(Ops, SL);
1454 }
1455 
1456 // Widen a vector load from vec3 to vec4.
1457 SDValue AMDGPUTargetLowering::WidenVectorLoad(SDValue Op,
1458                                               SelectionDAG &DAG) const {
1459   LoadSDNode *Load = cast<LoadSDNode>(Op);
1460   EVT VT = Op.getValueType();
1461   assert(VT.getVectorNumElements() == 3);
1462   SDValue BasePtr = Load->getBasePtr();
1463   EVT MemVT = Load->getMemoryVT();
1464   SDLoc SL(Op);
1465   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1466   unsigned BaseAlign = Load->getAlignment();
1467 
1468   EVT WideVT =
1469       EVT::getVectorVT(*DAG.getContext(), VT.getVectorElementType(), 4);
1470   EVT WideMemVT =
1471       EVT::getVectorVT(*DAG.getContext(), MemVT.getVectorElementType(), 4);
1472   SDValue WideLoad = DAG.getExtLoad(
1473       Load->getExtensionType(), SL, WideVT, Load->getChain(), BasePtr, SrcValue,
1474       WideMemVT, BaseAlign, Load->getMemOperand()->getFlags());
1475   return DAG.getMergeValues(
1476       {DAG.getNode(ISD::EXTRACT_SUBVECTOR, SL, VT, WideLoad,
1477                    DAG.getConstant(0, SL, getVectorIdxTy(DAG.getDataLayout()))),
1478        WideLoad.getValue(1)},
1479       SL);
1480 }
1481 
1482 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1483                                                SelectionDAG &DAG) const {
1484   StoreSDNode *Store = cast<StoreSDNode>(Op);
1485   SDValue Val = Store->getValue();
1486   EVT VT = Val.getValueType();
1487 
1488   // If this is a 2 element vector, we really want to scalarize and not create
1489   // weird 1 element vectors.
1490   if (VT.getVectorNumElements() == 2)
1491     return scalarizeVectorStore(Store, DAG);
1492 
1493   EVT MemVT = Store->getMemoryVT();
1494   SDValue Chain = Store->getChain();
1495   SDValue BasePtr = Store->getBasePtr();
1496   SDLoc SL(Op);
1497 
1498   EVT LoVT, HiVT;
1499   EVT LoMemVT, HiMemVT;
1500   SDValue Lo, Hi;
1501 
1502   std::tie(LoVT, HiVT) = getSplitDestVTs(VT, DAG);
1503   std::tie(LoMemVT, HiMemVT) = getSplitDestVTs(MemVT, DAG);
1504   std::tie(Lo, Hi) = splitVector(Val, SL, LoVT, HiVT, DAG);
1505 
1506   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1507 
1508   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1509   unsigned BaseAlign = Store->getAlignment();
1510   unsigned Size = LoMemVT.getStoreSize();
1511   unsigned HiAlign = MinAlign(BaseAlign, Size);
1512 
1513   SDValue LoStore =
1514       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1515                         Store->getMemOperand()->getFlags());
1516   SDValue HiStore =
1517       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1518                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1519 
1520   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1521 }
1522 
1523 // This is a shortcut for integer division because we have fast i32<->f32
1524 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1525 // float is enough to accurately represent up to a 24-bit signed integer.
1526 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1527                                             bool Sign) const {
1528   SDLoc DL(Op);
1529   EVT VT = Op.getValueType();
1530   SDValue LHS = Op.getOperand(0);
1531   SDValue RHS = Op.getOperand(1);
1532   MVT IntVT = MVT::i32;
1533   MVT FltVT = MVT::f32;
1534 
1535   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1536   if (LHSSignBits < 9)
1537     return SDValue();
1538 
1539   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1540   if (RHSSignBits < 9)
1541     return SDValue();
1542 
1543   unsigned BitSize = VT.getSizeInBits();
1544   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1545   unsigned DivBits = BitSize - SignBits;
1546   if (Sign)
1547     ++DivBits;
1548 
1549   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1550   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1551 
1552   SDValue jq = DAG.getConstant(1, DL, IntVT);
1553 
1554   if (Sign) {
1555     // char|short jq = ia ^ ib;
1556     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1557 
1558     // jq = jq >> (bitsize - 2)
1559     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1560                      DAG.getConstant(BitSize - 2, DL, VT));
1561 
1562     // jq = jq | 0x1
1563     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1564   }
1565 
1566   // int ia = (int)LHS;
1567   SDValue ia = LHS;
1568 
1569   // int ib, (int)RHS;
1570   SDValue ib = RHS;
1571 
1572   // float fa = (float)ia;
1573   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1574 
1575   // float fb = (float)ib;
1576   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1577 
1578   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1579                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1580 
1581   // fq = trunc(fq);
1582   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1583 
1584   // float fqneg = -fq;
1585   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1586 
1587   MachineFunction &MF = DAG.getMachineFunction();
1588   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
1589 
1590   // float fr = mad(fqneg, fb, fa);
1591   unsigned OpCode = MFI->getMode().FP32Denormals ?
1592                     (unsigned)AMDGPUISD::FMAD_FTZ :
1593                     (unsigned)ISD::FMAD;
1594   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1595 
1596   // int iq = (int)fq;
1597   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1598 
1599   // fr = fabs(fr);
1600   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1601 
1602   // fb = fabs(fb);
1603   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1604 
1605   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1606 
1607   // int cv = fr >= fb;
1608   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1609 
1610   // jq = (cv ? jq : 0);
1611   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1612 
1613   // dst = iq + jq;
1614   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1615 
1616   // Rem needs compensation, it's easier to recompute it
1617   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1618   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1619 
1620   // Truncate to number of bits this divide really is.
1621   if (Sign) {
1622     SDValue InRegSize
1623       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1624     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1625     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1626   } else {
1627     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1628     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1629     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1630   }
1631 
1632   return DAG.getMergeValues({ Div, Rem }, DL);
1633 }
1634 
1635 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1636                                       SelectionDAG &DAG,
1637                                       SmallVectorImpl<SDValue> &Results) const {
1638   SDLoc DL(Op);
1639   EVT VT = Op.getValueType();
1640 
1641   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1642 
1643   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1644 
1645   SDValue One = DAG.getConstant(1, DL, HalfVT);
1646   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1647 
1648   //HiLo split
1649   SDValue LHS = Op.getOperand(0);
1650   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1651   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1652 
1653   SDValue RHS = Op.getOperand(1);
1654   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1655   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1656 
1657   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1658       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1659 
1660     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1661                               LHS_Lo, RHS_Lo);
1662 
1663     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1664     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1665 
1666     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1667     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1668     return;
1669   }
1670 
1671   if (isTypeLegal(MVT::i64)) {
1672     MachineFunction &MF = DAG.getMachineFunction();
1673     const SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
1674 
1675     // Compute denominator reciprocal.
1676     unsigned FMAD = MFI->getMode().FP32Denormals ?
1677                     (unsigned)AMDGPUISD::FMAD_FTZ :
1678                     (unsigned)ISD::FMAD;
1679 
1680     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1681     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1682     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1683       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1684       Cvt_Lo);
1685     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1686     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1687       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1688     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1689       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1690     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1691     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1692       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1693       Mul1);
1694     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1695     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1696     SDValue Rcp64 = DAG.getBitcast(VT,
1697                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1698 
1699     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1700     SDValue One64  = DAG.getConstant(1, DL, VT);
1701     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1702     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1703 
1704     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1705     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1706     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1707     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1708                                     Zero);
1709     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1710                                     One);
1711 
1712     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1713                                   Mulhi1_Lo, Zero1);
1714     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1715                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1716     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1717     SDValue Add1 = DAG.getBitcast(VT,
1718                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1719 
1720     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1721     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1722     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1723                                     Zero);
1724     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1725                                     One);
1726 
1727     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1728                                   Mulhi2_Lo, Zero1);
1729     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1730                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1731     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1732                                   Zero, Add2_Lo.getValue(1));
1733     SDValue Add2 = DAG.getBitcast(VT,
1734                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1735     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1736 
1737     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1738 
1739     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1740     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1741     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1742                                   Mul3_Lo, Zero1);
1743     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1744                                   Mul3_Hi, Sub1_Lo.getValue(1));
1745     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1746     SDValue Sub1 = DAG.getBitcast(VT,
1747                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1748 
1749     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1750     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1751                                  ISD::SETUGE);
1752     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1753                                  ISD::SETUGE);
1754     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1755 
1756     // TODO: Here and below portions of the code can be enclosed into if/endif.
1757     // Currently control flow is unconditional and we have 4 selects after
1758     // potential endif to substitute PHIs.
1759 
1760     // if C3 != 0 ...
1761     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1762                                   RHS_Lo, Zero1);
1763     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1764                                   RHS_Hi, Sub1_Lo.getValue(1));
1765     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1766                                   Zero, Sub2_Lo.getValue(1));
1767     SDValue Sub2 = DAG.getBitcast(VT,
1768                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1769 
1770     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1771 
1772     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1773                                  ISD::SETUGE);
1774     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1775                                  ISD::SETUGE);
1776     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1777 
1778     // if (C6 != 0)
1779     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1780 
1781     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1782                                   RHS_Lo, Zero1);
1783     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1784                                   RHS_Hi, Sub2_Lo.getValue(1));
1785     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1786                                   Zero, Sub3_Lo.getValue(1));
1787     SDValue Sub3 = DAG.getBitcast(VT,
1788                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1789 
1790     // endif C6
1791     // endif C3
1792 
1793     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1794     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1795 
1796     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1797     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1798 
1799     Results.push_back(Div);
1800     Results.push_back(Rem);
1801 
1802     return;
1803   }
1804 
1805   // r600 expandion.
1806   // Get Speculative values
1807   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1808   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1809 
1810   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1811   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1812   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1813 
1814   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1815   SDValue DIV_Lo = Zero;
1816 
1817   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1818 
1819   for (unsigned i = 0; i < halfBitWidth; ++i) {
1820     const unsigned bitPos = halfBitWidth - i - 1;
1821     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1822     // Get value of high bit
1823     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1824     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1825     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1826 
1827     // Shift
1828     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1829     // Add LHS high bit
1830     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1831 
1832     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1833     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1834 
1835     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1836 
1837     // Update REM
1838     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1839     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1840   }
1841 
1842   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1843   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1844   Results.push_back(DIV);
1845   Results.push_back(REM);
1846 }
1847 
1848 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1849                                            SelectionDAG &DAG) const {
1850   SDLoc DL(Op);
1851   EVT VT = Op.getValueType();
1852 
1853   if (VT == MVT::i64) {
1854     SmallVector<SDValue, 2> Results;
1855     LowerUDIVREM64(Op, DAG, Results);
1856     return DAG.getMergeValues(Results, DL);
1857   }
1858 
1859   if (VT == MVT::i32) {
1860     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1861       return Res;
1862   }
1863 
1864   SDValue Num = Op.getOperand(0);
1865   SDValue Den = Op.getOperand(1);
1866 
1867   // RCP =  URECIP(Den) = 2^32 / Den + e
1868   // e is rounding error.
1869   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1870 
1871   // RCP_LO = mul(RCP, Den) */
1872   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1873 
1874   // RCP_HI = mulhu (RCP, Den) */
1875   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1876 
1877   // NEG_RCP_LO = -RCP_LO
1878   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1879                                                      RCP_LO);
1880 
1881   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1882   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1883                                            NEG_RCP_LO, RCP_LO,
1884                                            ISD::SETEQ);
1885   // Calculate the rounding error from the URECIP instruction
1886   // E = mulhu(ABS_RCP_LO, RCP)
1887   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1888 
1889   // RCP_A_E = RCP + E
1890   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1891 
1892   // RCP_S_E = RCP - E
1893   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1894 
1895   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1896   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1897                                      RCP_A_E, RCP_S_E,
1898                                      ISD::SETEQ);
1899   // Quotient = mulhu(Tmp0, Num)
1900   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1901 
1902   // Num_S_Remainder = Quotient * Den
1903   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1904 
1905   // Remainder = Num - Num_S_Remainder
1906   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1907 
1908   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1909   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1910                                                  DAG.getConstant(-1, DL, VT),
1911                                                  DAG.getConstant(0, DL, VT),
1912                                                  ISD::SETUGE);
1913   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1914   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1915                                                   Num_S_Remainder,
1916                                                   DAG.getConstant(-1, DL, VT),
1917                                                   DAG.getConstant(0, DL, VT),
1918                                                   ISD::SETUGE);
1919   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1920   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1921                                                Remainder_GE_Zero);
1922 
1923   // Calculate Division result:
1924 
1925   // Quotient_A_One = Quotient + 1
1926   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1927                                        DAG.getConstant(1, DL, VT));
1928 
1929   // Quotient_S_One = Quotient - 1
1930   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1931                                        DAG.getConstant(1, DL, VT));
1932 
1933   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1934   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1935                                      Quotient, Quotient_A_One, ISD::SETEQ);
1936 
1937   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1938   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1939                             Quotient_S_One, Div, ISD::SETEQ);
1940 
1941   // Calculate Rem result:
1942 
1943   // Remainder_S_Den = Remainder - Den
1944   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1945 
1946   // Remainder_A_Den = Remainder + Den
1947   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1948 
1949   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1950   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1951                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1952 
1953   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1954   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1955                             Remainder_A_Den, Rem, ISD::SETEQ);
1956   SDValue Ops[2] = {
1957     Div,
1958     Rem
1959   };
1960   return DAG.getMergeValues(Ops, DL);
1961 }
1962 
1963 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
1964                                            SelectionDAG &DAG) const {
1965   SDLoc DL(Op);
1966   EVT VT = Op.getValueType();
1967 
1968   SDValue LHS = Op.getOperand(0);
1969   SDValue RHS = Op.getOperand(1);
1970 
1971   SDValue Zero = DAG.getConstant(0, DL, VT);
1972   SDValue NegOne = DAG.getConstant(-1, DL, VT);
1973 
1974   if (VT == MVT::i32) {
1975     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
1976       return Res;
1977   }
1978 
1979   if (VT == MVT::i64 &&
1980       DAG.ComputeNumSignBits(LHS) > 32 &&
1981       DAG.ComputeNumSignBits(RHS) > 32) {
1982     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1983 
1984     //HiLo split
1985     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1986     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1987     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1988                                  LHS_Lo, RHS_Lo);
1989     SDValue Res[2] = {
1990       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
1991       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
1992     };
1993     return DAG.getMergeValues(Res, DL);
1994   }
1995 
1996   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
1997   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
1998   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
1999   SDValue RSign = LHSign; // Remainder sign is the same as LHS
2000 
2001   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
2002   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
2003 
2004   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
2005   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
2006 
2007   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
2008   SDValue Rem = Div.getValue(1);
2009 
2010   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
2011   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
2012 
2013   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
2014   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
2015 
2016   SDValue Res[2] = {
2017     Div,
2018     Rem
2019   };
2020   return DAG.getMergeValues(Res, DL);
2021 }
2022 
2023 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2024 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2025   SDLoc SL(Op);
2026   EVT VT = Op.getValueType();
2027   SDValue X = Op.getOperand(0);
2028   SDValue Y = Op.getOperand(1);
2029 
2030   // TODO: Should this propagate fast-math-flags?
2031 
2032   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2033   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2034   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2035 
2036   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2037 }
2038 
2039 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2040   SDLoc SL(Op);
2041   SDValue Src = Op.getOperand(0);
2042 
2043   // result = trunc(src)
2044   // if (src > 0.0 && src != result)
2045   //   result += 1.0
2046 
2047   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2048 
2049   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2050   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2051 
2052   EVT SetCCVT =
2053       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2054 
2055   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2056   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2057   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2058 
2059   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2060   // TODO: Should this propagate fast-math-flags?
2061   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2062 }
2063 
2064 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2065                                   SelectionDAG &DAG) {
2066   const unsigned FractBits = 52;
2067   const unsigned ExpBits = 11;
2068 
2069   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2070                                 Hi,
2071                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2072                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2073   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2074                             DAG.getConstant(1023, SL, MVT::i32));
2075 
2076   return Exp;
2077 }
2078 
2079 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2080   SDLoc SL(Op);
2081   SDValue Src = Op.getOperand(0);
2082 
2083   assert(Op.getValueType() == MVT::f64);
2084 
2085   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2086   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2087 
2088   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2089 
2090   // Extract the upper half, since this is where we will find the sign and
2091   // exponent.
2092   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2093 
2094   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2095 
2096   const unsigned FractBits = 52;
2097 
2098   // Extract the sign bit.
2099   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2100   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2101 
2102   // Extend back to 64-bits.
2103   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2104   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2105 
2106   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2107   const SDValue FractMask
2108     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2109 
2110   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2111   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2112   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2113 
2114   EVT SetCCVT =
2115       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2116 
2117   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2118 
2119   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2120   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2121 
2122   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2123   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2124 
2125   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2126 }
2127 
2128 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2129   SDLoc SL(Op);
2130   SDValue Src = Op.getOperand(0);
2131 
2132   assert(Op.getValueType() == MVT::f64);
2133 
2134   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2135   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2136   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2137 
2138   // TODO: Should this propagate fast-math-flags?
2139 
2140   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2141   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2142 
2143   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2144 
2145   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2146   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2147 
2148   EVT SetCCVT =
2149       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2150   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2151 
2152   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2153 }
2154 
2155 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2156   // FNEARBYINT and FRINT are the same, except in their handling of FP
2157   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2158   // rint, so just treat them as equivalent.
2159   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2160 }
2161 
2162 // XXX - May require not supporting f32 denormals?
2163 
2164 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2165 // compare and vselect end up producing worse code than scalarizing the whole
2166 // operation.
2167 SDValue AMDGPUTargetLowering::LowerFROUND_LegalFTRUNC(SDValue Op,
2168                                                       SelectionDAG &DAG) const {
2169   SDLoc SL(Op);
2170   SDValue X = Op.getOperand(0);
2171   EVT VT = Op.getValueType();
2172 
2173   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2174 
2175   // TODO: Should this propagate fast-math-flags?
2176 
2177   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2178 
2179   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2180 
2181   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2182   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2183   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2184 
2185   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2186 
2187   EVT SetCCVT =
2188       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2189 
2190   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2191 
2192   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2193 
2194   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2195 }
2196 
2197 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
2198   SDLoc SL(Op);
2199   SDValue X = Op.getOperand(0);
2200 
2201   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
2202 
2203   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2204   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2205   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
2206   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
2207   EVT SetCCVT =
2208       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2209 
2210   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
2211 
2212   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
2213 
2214   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2215 
2216   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
2217                                        MVT::i64);
2218 
2219   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
2220   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
2221                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
2222                                           MVT::i64),
2223                           Exp);
2224 
2225   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
2226   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
2227                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
2228                               ISD::SETNE);
2229 
2230   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
2231                              D, DAG.getConstant(0, SL, MVT::i64));
2232   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
2233 
2234   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
2235   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
2236 
2237   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2238   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2239   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
2240 
2241   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
2242                             ExpEqNegOne,
2243                             DAG.getConstantFP(1.0, SL, MVT::f64),
2244                             DAG.getConstantFP(0.0, SL, MVT::f64));
2245 
2246   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
2247 
2248   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
2249   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
2250 
2251   return K;
2252 }
2253 
2254 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2255   EVT VT = Op.getValueType();
2256 
2257   if (isOperationLegal(ISD::FTRUNC, VT))
2258     return LowerFROUND_LegalFTRUNC(Op, DAG);
2259 
2260   if (VT == MVT::f64)
2261     return LowerFROUND64(Op, DAG);
2262 
2263   llvm_unreachable("unhandled type");
2264 }
2265 
2266 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2267   SDLoc SL(Op);
2268   SDValue Src = Op.getOperand(0);
2269 
2270   // result = trunc(src);
2271   // if (src < 0.0 && src != result)
2272   //   result += -1.0.
2273 
2274   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2275 
2276   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2277   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2278 
2279   EVT SetCCVT =
2280       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2281 
2282   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2283   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2284   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2285 
2286   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2287   // TODO: Should this propagate fast-math-flags?
2288   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2289 }
2290 
2291 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2292                                         double Log2BaseInverted) const {
2293   EVT VT = Op.getValueType();
2294 
2295   SDLoc SL(Op);
2296   SDValue Operand = Op.getOperand(0);
2297   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2298   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2299 
2300   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2301 }
2302 
2303 // exp2(M_LOG2E_F * f);
2304 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2305   EVT VT = Op.getValueType();
2306   SDLoc SL(Op);
2307   SDValue Src = Op.getOperand(0);
2308 
2309   const SDValue K = DAG.getConstantFP(numbers::log2e, SL, VT);
2310   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2311   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2312 }
2313 
2314 static bool isCtlzOpc(unsigned Opc) {
2315   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2316 }
2317 
2318 static bool isCttzOpc(unsigned Opc) {
2319   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2320 }
2321 
2322 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2323   SDLoc SL(Op);
2324   SDValue Src = Op.getOperand(0);
2325   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2326                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2327 
2328   unsigned ISDOpc, NewOpc;
2329   if (isCtlzOpc(Op.getOpcode())) {
2330     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2331     NewOpc = AMDGPUISD::FFBH_U32;
2332   } else if (isCttzOpc(Op.getOpcode())) {
2333     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2334     NewOpc = AMDGPUISD::FFBL_B32;
2335   } else
2336     llvm_unreachable("Unexpected OPCode!!!");
2337 
2338 
2339   if (ZeroUndef && Src.getValueType() == MVT::i32)
2340     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2341 
2342   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2343 
2344   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2345   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2346 
2347   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2348   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2349 
2350   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2351                                    *DAG.getContext(), MVT::i32);
2352 
2353   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2354   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2355 
2356   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2357   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2358 
2359   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2360   SDValue Add, NewOpr;
2361   if (isCtlzOpc(Op.getOpcode())) {
2362     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2363     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2364     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2365   } else {
2366     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2367     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2368     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2369   }
2370 
2371   if (!ZeroUndef) {
2372     // Test if the full 64-bit input is zero.
2373 
2374     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2375     // which we probably don't want.
2376     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2377     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2378     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2379 
2380     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2381     // with the same cycles, otherwise it is slower.
2382     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2383     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2384 
2385     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2386 
2387     // The instruction returns -1 for 0 input, but the defined intrinsic
2388     // behavior is to return the number of bits.
2389     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2390                          SrcIsZero, Bits32, NewOpr);
2391   }
2392 
2393   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2394 }
2395 
2396 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2397                                                bool Signed) const {
2398   // Unsigned
2399   // cul2f(ulong u)
2400   //{
2401   //  uint lz = clz(u);
2402   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2403   //  u = (u << lz) & 0x7fffffffffffffffUL;
2404   //  ulong t = u & 0xffffffffffUL;
2405   //  uint v = (e << 23) | (uint)(u >> 40);
2406   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2407   //  return as_float(v + r);
2408   //}
2409   // Signed
2410   // cl2f(long l)
2411   //{
2412   //  long s = l >> 63;
2413   //  float r = cul2f((l + s) ^ s);
2414   //  return s ? -r : r;
2415   //}
2416 
2417   SDLoc SL(Op);
2418   SDValue Src = Op.getOperand(0);
2419   SDValue L = Src;
2420 
2421   SDValue S;
2422   if (Signed) {
2423     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2424     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2425 
2426     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2427     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2428   }
2429 
2430   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2431                                    *DAG.getContext(), MVT::f32);
2432 
2433 
2434   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2435   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2436   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2437   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2438 
2439   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2440   SDValue E = DAG.getSelect(SL, MVT::i32,
2441     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2442     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2443     ZeroI32);
2444 
2445   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2446     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2447     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2448 
2449   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2450                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2451 
2452   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2453                              U, DAG.getConstant(40, SL, MVT::i64));
2454 
2455   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2456     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2457     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2458 
2459   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2460   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2461   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2462 
2463   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2464 
2465   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2466 
2467   SDValue R = DAG.getSelect(SL, MVT::i32,
2468     RCmp,
2469     One,
2470     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2471   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2472   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2473 
2474   if (!Signed)
2475     return R;
2476 
2477   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2478   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2479 }
2480 
2481 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2482                                                bool Signed) const {
2483   SDLoc SL(Op);
2484   SDValue Src = Op.getOperand(0);
2485 
2486   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2487 
2488   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2489                            DAG.getConstant(0, SL, MVT::i32));
2490   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2491                            DAG.getConstant(1, SL, MVT::i32));
2492 
2493   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2494                               SL, MVT::f64, Hi);
2495 
2496   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2497 
2498   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2499                               DAG.getConstant(32, SL, MVT::i32));
2500   // TODO: Should this propagate fast-math-flags?
2501   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2502 }
2503 
2504 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2505                                                SelectionDAG &DAG) const {
2506   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2507          "operation should be legal");
2508 
2509   // TODO: Factor out code common with LowerSINT_TO_FP.
2510 
2511   EVT DestVT = Op.getValueType();
2512   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2513     SDLoc DL(Op);
2514     SDValue Src = Op.getOperand(0);
2515 
2516     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2517     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2518     SDValue FPRound =
2519         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2520 
2521     return FPRound;
2522   }
2523 
2524   if (DestVT == MVT::f32)
2525     return LowerINT_TO_FP32(Op, DAG, false);
2526 
2527   assert(DestVT == MVT::f64);
2528   return LowerINT_TO_FP64(Op, DAG, false);
2529 }
2530 
2531 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2532                                               SelectionDAG &DAG) const {
2533   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2534          "operation should be legal");
2535 
2536   // TODO: Factor out code common with LowerUINT_TO_FP.
2537 
2538   EVT DestVT = Op.getValueType();
2539   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2540     SDLoc DL(Op);
2541     SDValue Src = Op.getOperand(0);
2542 
2543     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2544     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2545     SDValue FPRound =
2546         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2547 
2548     return FPRound;
2549   }
2550 
2551   if (DestVT == MVT::f32)
2552     return LowerINT_TO_FP32(Op, DAG, true);
2553 
2554   assert(DestVT == MVT::f64);
2555   return LowerINT_TO_FP64(Op, DAG, true);
2556 }
2557 
2558 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2559                                                bool Signed) const {
2560   SDLoc SL(Op);
2561 
2562   SDValue Src = Op.getOperand(0);
2563 
2564   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2565 
2566   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2567                                  MVT::f64);
2568   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2569                                  MVT::f64);
2570   // TODO: Should this propagate fast-math-flags?
2571   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2572 
2573   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2574 
2575 
2576   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2577 
2578   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2579                            MVT::i32, FloorMul);
2580   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2581 
2582   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2583 
2584   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2585 }
2586 
2587 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2588   SDLoc DL(Op);
2589   SDValue N0 = Op.getOperand(0);
2590 
2591   // Convert to target node to get known bits
2592   if (N0.getValueType() == MVT::f32)
2593     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2594 
2595   if (getTargetMachine().Options.UnsafeFPMath) {
2596     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2597     return SDValue();
2598   }
2599 
2600   assert(N0.getSimpleValueType() == MVT::f64);
2601 
2602   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2603   const unsigned ExpMask = 0x7ff;
2604   const unsigned ExpBiasf64 = 1023;
2605   const unsigned ExpBiasf16 = 15;
2606   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2607   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2608   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2609   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2610                            DAG.getConstant(32, DL, MVT::i64));
2611   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2612   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2613   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2614                           DAG.getConstant(20, DL, MVT::i64));
2615   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2616                   DAG.getConstant(ExpMask, DL, MVT::i32));
2617   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2618   // add the f16 bias (15) to get the biased exponent for the f16 format.
2619   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2620                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2621 
2622   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2623                           DAG.getConstant(8, DL, MVT::i32));
2624   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2625                   DAG.getConstant(0xffe, DL, MVT::i32));
2626 
2627   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2628                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2629   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2630 
2631   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2632   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2633 
2634   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2635   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2636       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2637                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2638 
2639   // N = M | (E << 12);
2640   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2641       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2642                   DAG.getConstant(12, DL, MVT::i32)));
2643 
2644   // B = clamp(1-E, 0, 13);
2645   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2646                                   One, E);
2647   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2648   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2649                   DAG.getConstant(13, DL, MVT::i32));
2650 
2651   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2652                                    DAG.getConstant(0x1000, DL, MVT::i32));
2653 
2654   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2655   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2656   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2657   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2658 
2659   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2660   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2661                               DAG.getConstant(0x7, DL, MVT::i32));
2662   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2663                   DAG.getConstant(2, DL, MVT::i32));
2664   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2665                                One, Zero, ISD::SETEQ);
2666   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2667                                One, Zero, ISD::SETGT);
2668   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2669   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2670 
2671   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2672                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2673   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2674                       I, V, ISD::SETEQ);
2675 
2676   // Extract the sign bit.
2677   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2678                             DAG.getConstant(16, DL, MVT::i32));
2679   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2680                      DAG.getConstant(0x8000, DL, MVT::i32));
2681 
2682   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2683   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2684 }
2685 
2686 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2687                                               SelectionDAG &DAG) const {
2688   SDValue Src = Op.getOperand(0);
2689 
2690   // TODO: Factor out code common with LowerFP_TO_UINT.
2691 
2692   EVT SrcVT = Src.getValueType();
2693   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2694     SDLoc DL(Op);
2695 
2696     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2697     SDValue FpToInt32 =
2698         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2699 
2700     return FpToInt32;
2701   }
2702 
2703   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2704     return LowerFP64_TO_INT(Op, DAG, true);
2705 
2706   return SDValue();
2707 }
2708 
2709 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2710                                               SelectionDAG &DAG) const {
2711   SDValue Src = Op.getOperand(0);
2712 
2713   // TODO: Factor out code common with LowerFP_TO_SINT.
2714 
2715   EVT SrcVT = Src.getValueType();
2716   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2717     SDLoc DL(Op);
2718 
2719     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2720     SDValue FpToInt32 =
2721         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2722 
2723     return FpToInt32;
2724   }
2725 
2726   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2727     return LowerFP64_TO_INT(Op, DAG, false);
2728 
2729   return SDValue();
2730 }
2731 
2732 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2733                                                      SelectionDAG &DAG) const {
2734   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2735   MVT VT = Op.getSimpleValueType();
2736   MVT ScalarVT = VT.getScalarType();
2737 
2738   assert(VT.isVector());
2739 
2740   SDValue Src = Op.getOperand(0);
2741   SDLoc DL(Op);
2742 
2743   // TODO: Don't scalarize on Evergreen?
2744   unsigned NElts = VT.getVectorNumElements();
2745   SmallVector<SDValue, 8> Args;
2746   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2747 
2748   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2749   for (unsigned I = 0; I < NElts; ++I)
2750     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2751 
2752   return DAG.getBuildVector(VT, DL, Args);
2753 }
2754 
2755 //===----------------------------------------------------------------------===//
2756 // Custom DAG optimizations
2757 //===----------------------------------------------------------------------===//
2758 
2759 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2760   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2761 }
2762 
2763 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2764   EVT VT = Op.getValueType();
2765   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2766                                      // as unsigned 24-bit values.
2767     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2768 }
2769 
2770 static SDValue simplifyI24(SDNode *Node24,
2771                            TargetLowering::DAGCombinerInfo &DCI) {
2772   SelectionDAG &DAG = DCI.DAG;
2773   bool IsIntrin = Node24->getOpcode() == ISD::INTRINSIC_WO_CHAIN;
2774 
2775   SDValue LHS = IsIntrin ? Node24->getOperand(1) : Node24->getOperand(0);
2776   SDValue RHS = IsIntrin ? Node24->getOperand(2) : Node24->getOperand(1);
2777   unsigned NewOpcode = Node24->getOpcode();
2778   if (IsIntrin) {
2779     unsigned IID = cast<ConstantSDNode>(Node24->getOperand(0))->getZExtValue();
2780     NewOpcode = IID == Intrinsic::amdgcn_mul_i24 ?
2781       AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
2782   }
2783 
2784   APInt Demanded = APInt::getLowBitsSet(LHS.getValueSizeInBits(), 24);
2785 
2786   // First try to simplify using GetDemandedBits which allows the operands to
2787   // have other uses, but will only perform simplifications that involve
2788   // bypassing some nodes for this user.
2789   SDValue DemandedLHS = DAG.GetDemandedBits(LHS, Demanded);
2790   SDValue DemandedRHS = DAG.GetDemandedBits(RHS, Demanded);
2791   if (DemandedLHS || DemandedRHS)
2792     return DAG.getNode(NewOpcode, SDLoc(Node24), Node24->getVTList(),
2793                        DemandedLHS ? DemandedLHS : LHS,
2794                        DemandedRHS ? DemandedRHS : RHS);
2795 
2796   // Now try SimplifyDemandedBits which can simplify the nodes used by our
2797   // operands if this node is the only user.
2798   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2799   if (TLI.SimplifyDemandedBits(LHS, Demanded, DCI))
2800     return SDValue(Node24, 0);
2801   if (TLI.SimplifyDemandedBits(RHS, Demanded, DCI))
2802     return SDValue(Node24, 0);
2803 
2804   return SDValue();
2805 }
2806 
2807 template <typename IntTy>
2808 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2809                                uint32_t Width, const SDLoc &DL) {
2810   if (Width + Offset < 32) {
2811     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2812     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2813     return DAG.getConstant(Result, DL, MVT::i32);
2814   }
2815 
2816   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2817 }
2818 
2819 static bool hasVolatileUser(SDNode *Val) {
2820   for (SDNode *U : Val->uses()) {
2821     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2822       if (M->isVolatile())
2823         return true;
2824     }
2825   }
2826 
2827   return false;
2828 }
2829 
2830 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2831   // i32 vectors are the canonical memory type.
2832   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2833     return false;
2834 
2835   if (!VT.isByteSized())
2836     return false;
2837 
2838   unsigned Size = VT.getStoreSize();
2839 
2840   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2841     return false;
2842 
2843   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2844     return false;
2845 
2846   return true;
2847 }
2848 
2849 // Replace load of an illegal type with a store of a bitcast to a friendlier
2850 // type.
2851 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2852                                                  DAGCombinerInfo &DCI) const {
2853   if (!DCI.isBeforeLegalize())
2854     return SDValue();
2855 
2856   LoadSDNode *LN = cast<LoadSDNode>(N);
2857   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2858     return SDValue();
2859 
2860   SDLoc SL(N);
2861   SelectionDAG &DAG = DCI.DAG;
2862   EVT VT = LN->getMemoryVT();
2863 
2864   unsigned Size = VT.getStoreSize();
2865   unsigned Align = LN->getAlignment();
2866   if (Align < Size && isTypeLegal(VT)) {
2867     bool IsFast;
2868     unsigned AS = LN->getAddressSpace();
2869 
2870     // Expand unaligned loads earlier than legalization. Due to visitation order
2871     // problems during legalization, the emitted instructions to pack and unpack
2872     // the bytes again are not eliminated in the case of an unaligned copy.
2873     if (!allowsMisalignedMemoryAccesses(
2874             VT, AS, Align, LN->getMemOperand()->getFlags(), &IsFast)) {
2875       SDValue Ops[2];
2876 
2877       if (VT.isVector())
2878         std::tie(Ops[0], Ops[1]) = scalarizeVectorLoad(LN, DAG);
2879       else
2880         std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2881 
2882       return DAG.getMergeValues(Ops, SDLoc(N));
2883     }
2884 
2885     if (!IsFast)
2886       return SDValue();
2887   }
2888 
2889   if (!shouldCombineMemoryType(VT))
2890     return SDValue();
2891 
2892   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2893 
2894   SDValue NewLoad
2895     = DAG.getLoad(NewVT, SL, LN->getChain(),
2896                   LN->getBasePtr(), LN->getMemOperand());
2897 
2898   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2899   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2900   return SDValue(N, 0);
2901 }
2902 
2903 // Replace store of an illegal type with a store of a bitcast to a friendlier
2904 // type.
2905 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2906                                                   DAGCombinerInfo &DCI) const {
2907   if (!DCI.isBeforeLegalize())
2908     return SDValue();
2909 
2910   StoreSDNode *SN = cast<StoreSDNode>(N);
2911   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2912     return SDValue();
2913 
2914   EVT VT = SN->getMemoryVT();
2915   unsigned Size = VT.getStoreSize();
2916 
2917   SDLoc SL(N);
2918   SelectionDAG &DAG = DCI.DAG;
2919   unsigned Align = SN->getAlignment();
2920   if (Align < Size && isTypeLegal(VT)) {
2921     bool IsFast;
2922     unsigned AS = SN->getAddressSpace();
2923 
2924     // Expand unaligned stores earlier than legalization. Due to visitation
2925     // order problems during legalization, the emitted instructions to pack and
2926     // unpack the bytes again are not eliminated in the case of an unaligned
2927     // copy.
2928     if (!allowsMisalignedMemoryAccesses(
2929             VT, AS, Align, SN->getMemOperand()->getFlags(), &IsFast)) {
2930       if (VT.isVector())
2931         return scalarizeVectorStore(SN, DAG);
2932 
2933       return expandUnalignedStore(SN, DAG);
2934     }
2935 
2936     if (!IsFast)
2937       return SDValue();
2938   }
2939 
2940   if (!shouldCombineMemoryType(VT))
2941     return SDValue();
2942 
2943   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2944   SDValue Val = SN->getValue();
2945 
2946   //DCI.AddToWorklist(Val.getNode());
2947 
2948   bool OtherUses = !Val.hasOneUse();
2949   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2950   if (OtherUses) {
2951     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2952     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2953   }
2954 
2955   return DAG.getStore(SN->getChain(), SL, CastVal,
2956                       SN->getBasePtr(), SN->getMemOperand());
2957 }
2958 
2959 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2960 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2961 // issues.
2962 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2963                                                         DAGCombinerInfo &DCI) const {
2964   SelectionDAG &DAG = DCI.DAG;
2965   SDValue N0 = N->getOperand(0);
2966 
2967   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2968   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2969   if (N0.getOpcode() == ISD::TRUNCATE) {
2970     SDValue N1 = N->getOperand(1);
2971     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2972     SDLoc SL(N);
2973 
2974     SDValue Src = N0.getOperand(0);
2975     EVT SrcVT = Src.getValueType();
2976     if (SrcVT.bitsGE(ExtVT)) {
2977       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2978       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2979     }
2980   }
2981 
2982   return SDValue();
2983 }
2984 
2985 SDValue AMDGPUTargetLowering::performIntrinsicWOChainCombine(
2986   SDNode *N, DAGCombinerInfo &DCI) const {
2987   unsigned IID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
2988   switch (IID) {
2989   case Intrinsic::amdgcn_mul_i24:
2990   case Intrinsic::amdgcn_mul_u24:
2991     return simplifyI24(N, DCI);
2992   default:
2993     return SDValue();
2994   }
2995 }
2996 
2997 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
2998 /// binary operation \p Opc to it with the corresponding constant operands.
2999 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
3000   DAGCombinerInfo &DCI, const SDLoc &SL,
3001   unsigned Opc, SDValue LHS,
3002   uint32_t ValLo, uint32_t ValHi) const {
3003   SelectionDAG &DAG = DCI.DAG;
3004   SDValue Lo, Hi;
3005   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
3006 
3007   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
3008   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
3009 
3010   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
3011   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
3012 
3013   // Re-visit the ands. It's possible we eliminated one of them and it could
3014   // simplify the vector.
3015   DCI.AddToWorklist(Lo.getNode());
3016   DCI.AddToWorklist(Hi.getNode());
3017 
3018   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
3019   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3020 }
3021 
3022 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
3023                                                 DAGCombinerInfo &DCI) const {
3024   EVT VT = N->getValueType(0);
3025 
3026   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3027   if (!RHS)
3028     return SDValue();
3029 
3030   SDValue LHS = N->getOperand(0);
3031   unsigned RHSVal = RHS->getZExtValue();
3032   if (!RHSVal)
3033     return LHS;
3034 
3035   SDLoc SL(N);
3036   SelectionDAG &DAG = DCI.DAG;
3037 
3038   switch (LHS->getOpcode()) {
3039   default:
3040     break;
3041   case ISD::ZERO_EXTEND:
3042   case ISD::SIGN_EXTEND:
3043   case ISD::ANY_EXTEND: {
3044     SDValue X = LHS->getOperand(0);
3045 
3046     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
3047         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
3048       // Prefer build_vector as the canonical form if packed types are legal.
3049       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
3050       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
3051        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
3052       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
3053     }
3054 
3055     // shl (ext x) => zext (shl x), if shift does not overflow int
3056     if (VT != MVT::i64)
3057       break;
3058     KnownBits Known = DAG.computeKnownBits(X);
3059     unsigned LZ = Known.countMinLeadingZeros();
3060     if (LZ < RHSVal)
3061       break;
3062     EVT XVT = X.getValueType();
3063     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
3064     return DAG.getZExtOrTrunc(Shl, SL, VT);
3065   }
3066   }
3067 
3068   if (VT != MVT::i64)
3069     return SDValue();
3070 
3071   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3072 
3073   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3074   // common case, splitting this into a move and a 32-bit shift is faster and
3075   // the same code size.
3076   if (RHSVal < 32)
3077     return SDValue();
3078 
3079   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3080 
3081   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3082   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3083 
3084   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3085 
3086   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3087   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3088 }
3089 
3090 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3091                                                 DAGCombinerInfo &DCI) const {
3092   if (N->getValueType(0) != MVT::i64)
3093     return SDValue();
3094 
3095   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3096   if (!RHS)
3097     return SDValue();
3098 
3099   SelectionDAG &DAG = DCI.DAG;
3100   SDLoc SL(N);
3101   unsigned RHSVal = RHS->getZExtValue();
3102 
3103   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3104   if (RHSVal == 32) {
3105     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3106     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3107                                    DAG.getConstant(31, SL, MVT::i32));
3108 
3109     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3110     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3111   }
3112 
3113   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3114   if (RHSVal == 63) {
3115     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3116     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3117                                    DAG.getConstant(31, SL, MVT::i32));
3118     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3119     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3120   }
3121 
3122   return SDValue();
3123 }
3124 
3125 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3126                                                 DAGCombinerInfo &DCI) const {
3127   auto *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3128   if (!RHS)
3129     return SDValue();
3130 
3131   EVT VT = N->getValueType(0);
3132   SDValue LHS = N->getOperand(0);
3133   unsigned ShiftAmt = RHS->getZExtValue();
3134   SelectionDAG &DAG = DCI.DAG;
3135   SDLoc SL(N);
3136 
3137   // fold (srl (and x, c1 << c2), c2) -> (and (srl(x, c2), c1)
3138   // this improves the ability to match BFE patterns in isel.
3139   if (LHS.getOpcode() == ISD::AND) {
3140     if (auto *Mask = dyn_cast<ConstantSDNode>(LHS.getOperand(1))) {
3141       if (Mask->getAPIntValue().isShiftedMask() &&
3142           Mask->getAPIntValue().countTrailingZeros() == ShiftAmt) {
3143         return DAG.getNode(
3144             ISD::AND, SL, VT,
3145             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(0), N->getOperand(1)),
3146             DAG.getNode(ISD::SRL, SL, VT, LHS.getOperand(1), N->getOperand(1)));
3147       }
3148     }
3149   }
3150 
3151   if (VT != MVT::i64)
3152     return SDValue();
3153 
3154   if (ShiftAmt < 32)
3155     return SDValue();
3156 
3157   // srl i64:x, C for C >= 32
3158   // =>
3159   //   build_pair (srl hi_32(x), C - 32), 0
3160   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3161   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3162 
3163   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, LHS);
3164   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecOp, One);
3165 
3166   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3167   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3168 
3169   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3170 
3171   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3172 }
3173 
3174 SDValue AMDGPUTargetLowering::performTruncateCombine(
3175   SDNode *N, DAGCombinerInfo &DCI) const {
3176   SDLoc SL(N);
3177   SelectionDAG &DAG = DCI.DAG;
3178   EVT VT = N->getValueType(0);
3179   SDValue Src = N->getOperand(0);
3180 
3181   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3182   if (Src.getOpcode() == ISD::BITCAST && !VT.isVector()) {
3183     SDValue Vec = Src.getOperand(0);
3184     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3185       SDValue Elt0 = Vec.getOperand(0);
3186       EVT EltVT = Elt0.getValueType();
3187       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3188         if (EltVT.isFloatingPoint()) {
3189           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3190                              EltVT.changeTypeToInteger(), Elt0);
3191         }
3192 
3193         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3194       }
3195     }
3196   }
3197 
3198   // Equivalent of above for accessing the high element of a vector as an
3199   // integer operation.
3200   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3201   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3202     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3203       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3204         SDValue BV = stripBitcast(Src.getOperand(0));
3205         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3206             BV.getValueType().getVectorNumElements() == 2) {
3207           SDValue SrcElt = BV.getOperand(1);
3208           EVT SrcEltVT = SrcElt.getValueType();
3209           if (SrcEltVT.isFloatingPoint()) {
3210             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3211                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3212           }
3213 
3214           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3215         }
3216       }
3217     }
3218   }
3219 
3220   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3221   //
3222   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3223   //     i16 (trunc (srl (i32 (trunc x), K)))
3224   if (VT.getScalarSizeInBits() < 32) {
3225     EVT SrcVT = Src.getValueType();
3226     if (SrcVT.getScalarSizeInBits() > 32 &&
3227         (Src.getOpcode() == ISD::SRL ||
3228          Src.getOpcode() == ISD::SRA ||
3229          Src.getOpcode() == ISD::SHL)) {
3230       SDValue Amt = Src.getOperand(1);
3231       KnownBits Known = DAG.computeKnownBits(Amt);
3232       unsigned Size = VT.getScalarSizeInBits();
3233       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3234           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3235         EVT MidVT = VT.isVector() ?
3236           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3237                            VT.getVectorNumElements()) : MVT::i32;
3238 
3239         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3240         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3241                                     Src.getOperand(0));
3242         DCI.AddToWorklist(Trunc.getNode());
3243 
3244         if (Amt.getValueType() != NewShiftVT) {
3245           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3246           DCI.AddToWorklist(Amt.getNode());
3247         }
3248 
3249         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3250                                           Trunc, Amt);
3251         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3252       }
3253     }
3254   }
3255 
3256   return SDValue();
3257 }
3258 
3259 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3260 // instructions. If we only match on the legalized i64 mul expansion,
3261 // SimplifyDemandedBits will be unable to remove them because there will be
3262 // multiple uses due to the separate mul + mulh[su].
3263 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3264                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3265   if (Size <= 32) {
3266     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3267     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3268   }
3269 
3270   // Because we want to eliminate extension instructions before the
3271   // operation, we need to create a single user here (i.e. not the separate
3272   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3273 
3274   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3275 
3276   SDValue Mul = DAG.getNode(MulOpc, SL,
3277                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3278 
3279   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3280                      Mul.getValue(0), Mul.getValue(1));
3281 }
3282 
3283 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3284                                                 DAGCombinerInfo &DCI) const {
3285   EVT VT = N->getValueType(0);
3286 
3287   unsigned Size = VT.getSizeInBits();
3288   if (VT.isVector() || Size > 64)
3289     return SDValue();
3290 
3291   // There are i16 integer mul/mad.
3292   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3293     return SDValue();
3294 
3295   SelectionDAG &DAG = DCI.DAG;
3296   SDLoc DL(N);
3297 
3298   SDValue N0 = N->getOperand(0);
3299   SDValue N1 = N->getOperand(1);
3300 
3301   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3302   // in the source into any_extends if the result of the mul is truncated. Since
3303   // we can assume the high bits are whatever we want, use the underlying value
3304   // to avoid the unknown high bits from interfering.
3305   if (N0.getOpcode() == ISD::ANY_EXTEND)
3306     N0 = N0.getOperand(0);
3307 
3308   if (N1.getOpcode() == ISD::ANY_EXTEND)
3309     N1 = N1.getOperand(0);
3310 
3311   SDValue Mul;
3312 
3313   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3314     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3315     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3316     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3317   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3318     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3319     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3320     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3321   } else {
3322     return SDValue();
3323   }
3324 
3325   // We need to use sext even for MUL_U24, because MUL_U24 is used
3326   // for signed multiply of 8 and 16-bit types.
3327   return DAG.getSExtOrTrunc(Mul, DL, VT);
3328 }
3329 
3330 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3331                                                   DAGCombinerInfo &DCI) const {
3332   EVT VT = N->getValueType(0);
3333 
3334   if (!Subtarget->hasMulI24() || VT.isVector())
3335     return SDValue();
3336 
3337   SelectionDAG &DAG = DCI.DAG;
3338   SDLoc DL(N);
3339 
3340   SDValue N0 = N->getOperand(0);
3341   SDValue N1 = N->getOperand(1);
3342 
3343   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3344     return SDValue();
3345 
3346   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3347   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3348 
3349   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3350   DCI.AddToWorklist(Mulhi.getNode());
3351   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3352 }
3353 
3354 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3355                                                   DAGCombinerInfo &DCI) const {
3356   EVT VT = N->getValueType(0);
3357 
3358   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3359     return SDValue();
3360 
3361   SelectionDAG &DAG = DCI.DAG;
3362   SDLoc DL(N);
3363 
3364   SDValue N0 = N->getOperand(0);
3365   SDValue N1 = N->getOperand(1);
3366 
3367   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3368     return SDValue();
3369 
3370   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3371   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3372 
3373   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3374   DCI.AddToWorklist(Mulhi.getNode());
3375   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3376 }
3377 
3378 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3379   SDNode *N, DAGCombinerInfo &DCI) const {
3380   SelectionDAG &DAG = DCI.DAG;
3381 
3382   // Simplify demanded bits before splitting into multiple users.
3383   if (SDValue V = simplifyI24(N, DCI))
3384     return V;
3385 
3386   SDValue N0 = N->getOperand(0);
3387   SDValue N1 = N->getOperand(1);
3388 
3389   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3390 
3391   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3392   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3393 
3394   SDLoc SL(N);
3395 
3396   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3397   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3398   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3399 }
3400 
3401 static bool isNegativeOne(SDValue Val) {
3402   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3403     return C->isAllOnesValue();
3404   return false;
3405 }
3406 
3407 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3408                                           SDValue Op,
3409                                           const SDLoc &DL,
3410                                           unsigned Opc) const {
3411   EVT VT = Op.getValueType();
3412   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3413   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3414                               LegalVT != MVT::i16))
3415     return SDValue();
3416 
3417   if (VT != MVT::i32)
3418     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3419 
3420   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3421   if (VT != MVT::i32)
3422     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3423 
3424   return FFBX;
3425 }
3426 
3427 // The native instructions return -1 on 0 input. Optimize out a select that
3428 // produces -1 on 0.
3429 //
3430 // TODO: If zero is not undef, we could also do this if the output is compared
3431 // against the bitwidth.
3432 //
3433 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3434 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3435                                                  SDValue LHS, SDValue RHS,
3436                                                  DAGCombinerInfo &DCI) const {
3437   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3438   if (!CmpRhs || !CmpRhs->isNullValue())
3439     return SDValue();
3440 
3441   SelectionDAG &DAG = DCI.DAG;
3442   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3443   SDValue CmpLHS = Cond.getOperand(0);
3444 
3445   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3446                                            AMDGPUISD::FFBH_U32;
3447 
3448   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3449   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3450   if (CCOpcode == ISD::SETEQ &&
3451       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3452       RHS.getOperand(0) == CmpLHS &&
3453       isNegativeOne(LHS)) {
3454     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3455   }
3456 
3457   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3458   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3459   if (CCOpcode == ISD::SETNE &&
3460       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3461       LHS.getOperand(0) == CmpLHS &&
3462       isNegativeOne(RHS)) {
3463     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3464   }
3465 
3466   return SDValue();
3467 }
3468 
3469 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3470                                          unsigned Op,
3471                                          const SDLoc &SL,
3472                                          SDValue Cond,
3473                                          SDValue N1,
3474                                          SDValue N2) {
3475   SelectionDAG &DAG = DCI.DAG;
3476   EVT VT = N1.getValueType();
3477 
3478   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3479                                   N1.getOperand(0), N2.getOperand(0));
3480   DCI.AddToWorklist(NewSelect.getNode());
3481   return DAG.getNode(Op, SL, VT, NewSelect);
3482 }
3483 
3484 // Pull a free FP operation out of a select so it may fold into uses.
3485 //
3486 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3487 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3488 //
3489 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3490 // select c, (fabs x), +k -> fabs (select c, x, k)
3491 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3492                                     SDValue N) {
3493   SelectionDAG &DAG = DCI.DAG;
3494   SDValue Cond = N.getOperand(0);
3495   SDValue LHS = N.getOperand(1);
3496   SDValue RHS = N.getOperand(2);
3497 
3498   EVT VT = N.getValueType();
3499   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3500       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3501     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3502                                      SDLoc(N), Cond, LHS, RHS);
3503   }
3504 
3505   bool Inv = false;
3506   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3507     std::swap(LHS, RHS);
3508     Inv = true;
3509   }
3510 
3511   // TODO: Support vector constants.
3512   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3513   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3514     SDLoc SL(N);
3515     // If one side is an fneg/fabs and the other is a constant, we can push the
3516     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3517     SDValue NewLHS = LHS.getOperand(0);
3518     SDValue NewRHS = RHS;
3519 
3520     // Careful: if the neg can be folded up, don't try to pull it back down.
3521     bool ShouldFoldNeg = true;
3522 
3523     if (NewLHS.hasOneUse()) {
3524       unsigned Opc = NewLHS.getOpcode();
3525       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3526         ShouldFoldNeg = false;
3527       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3528         ShouldFoldNeg = false;
3529     }
3530 
3531     if (ShouldFoldNeg) {
3532       if (LHS.getOpcode() == ISD::FNEG)
3533         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3534       else if (CRHS->isNegative())
3535         return SDValue();
3536 
3537       if (Inv)
3538         std::swap(NewLHS, NewRHS);
3539 
3540       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3541                                       Cond, NewLHS, NewRHS);
3542       DCI.AddToWorklist(NewSelect.getNode());
3543       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3544     }
3545   }
3546 
3547   return SDValue();
3548 }
3549 
3550 
3551 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3552                                                    DAGCombinerInfo &DCI) const {
3553   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3554     return Folded;
3555 
3556   SDValue Cond = N->getOperand(0);
3557   if (Cond.getOpcode() != ISD::SETCC)
3558     return SDValue();
3559 
3560   EVT VT = N->getValueType(0);
3561   SDValue LHS = Cond.getOperand(0);
3562   SDValue RHS = Cond.getOperand(1);
3563   SDValue CC = Cond.getOperand(2);
3564 
3565   SDValue True = N->getOperand(1);
3566   SDValue False = N->getOperand(2);
3567 
3568   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3569     SelectionDAG &DAG = DCI.DAG;
3570     if (DAG.isConstantValueOfAnyType(True) &&
3571         !DAG.isConstantValueOfAnyType(False)) {
3572       // Swap cmp + select pair to move constant to false input.
3573       // This will allow using VOPC cndmasks more often.
3574       // select (setcc x, y), k, x -> select (setccinv x, y), x, k
3575 
3576       SDLoc SL(N);
3577       ISD::CondCode NewCC =
3578           getSetCCInverse(cast<CondCodeSDNode>(CC)->get(), LHS.getValueType());
3579 
3580       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3581       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3582     }
3583 
3584     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3585       SDValue MinMax
3586         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3587       // Revisit this node so we can catch min3/max3/med3 patterns.
3588       //DCI.AddToWorklist(MinMax.getNode());
3589       return MinMax;
3590     }
3591   }
3592 
3593   // There's no reason to not do this if the condition has other uses.
3594   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3595 }
3596 
3597 static bool isInv2Pi(const APFloat &APF) {
3598   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3599   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3600   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3601 
3602   return APF.bitwiseIsEqual(KF16) ||
3603          APF.bitwiseIsEqual(KF32) ||
3604          APF.bitwiseIsEqual(KF64);
3605 }
3606 
3607 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3608 // additional cost to negate them.
3609 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3610   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3611     if (C->isZero() && !C->isNegative())
3612       return true;
3613 
3614     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3615       return true;
3616   }
3617 
3618   return false;
3619 }
3620 
3621 static unsigned inverseMinMax(unsigned Opc) {
3622   switch (Opc) {
3623   case ISD::FMAXNUM:
3624     return ISD::FMINNUM;
3625   case ISD::FMINNUM:
3626     return ISD::FMAXNUM;
3627   case ISD::FMAXNUM_IEEE:
3628     return ISD::FMINNUM_IEEE;
3629   case ISD::FMINNUM_IEEE:
3630     return ISD::FMAXNUM_IEEE;
3631   case AMDGPUISD::FMAX_LEGACY:
3632     return AMDGPUISD::FMIN_LEGACY;
3633   case AMDGPUISD::FMIN_LEGACY:
3634     return  AMDGPUISD::FMAX_LEGACY;
3635   default:
3636     llvm_unreachable("invalid min/max opcode");
3637   }
3638 }
3639 
3640 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3641                                                  DAGCombinerInfo &DCI) const {
3642   SelectionDAG &DAG = DCI.DAG;
3643   SDValue N0 = N->getOperand(0);
3644   EVT VT = N->getValueType(0);
3645 
3646   unsigned Opc = N0.getOpcode();
3647 
3648   // If the input has multiple uses and we can either fold the negate down, or
3649   // the other uses cannot, give up. This both prevents unprofitable
3650   // transformations and infinite loops: we won't repeatedly try to fold around
3651   // a negate that has no 'good' form.
3652   if (N0.hasOneUse()) {
3653     // This may be able to fold into the source, but at a code size cost. Don't
3654     // fold if the fold into the user is free.
3655     if (allUsesHaveSourceMods(N, 0))
3656       return SDValue();
3657   } else {
3658     if (fnegFoldsIntoOp(Opc) &&
3659         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3660       return SDValue();
3661   }
3662 
3663   SDLoc SL(N);
3664   switch (Opc) {
3665   case ISD::FADD: {
3666     if (!mayIgnoreSignedZero(N0))
3667       return SDValue();
3668 
3669     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3670     SDValue LHS = N0.getOperand(0);
3671     SDValue RHS = N0.getOperand(1);
3672 
3673     if (LHS.getOpcode() != ISD::FNEG)
3674       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3675     else
3676       LHS = LHS.getOperand(0);
3677 
3678     if (RHS.getOpcode() != ISD::FNEG)
3679       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3680     else
3681       RHS = RHS.getOperand(0);
3682 
3683     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3684     if (Res.getOpcode() != ISD::FADD)
3685       return SDValue(); // Op got folded away.
3686     if (!N0.hasOneUse())
3687       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3688     return Res;
3689   }
3690   case ISD::FMUL:
3691   case AMDGPUISD::FMUL_LEGACY: {
3692     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3693     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3694     SDValue LHS = N0.getOperand(0);
3695     SDValue RHS = N0.getOperand(1);
3696 
3697     if (LHS.getOpcode() == ISD::FNEG)
3698       LHS = LHS.getOperand(0);
3699     else if (RHS.getOpcode() == ISD::FNEG)
3700       RHS = RHS.getOperand(0);
3701     else
3702       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3703 
3704     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3705     if (Res.getOpcode() != Opc)
3706       return SDValue(); // Op got folded away.
3707     if (!N0.hasOneUse())
3708       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3709     return Res;
3710   }
3711   case ISD::FMA:
3712   case ISD::FMAD: {
3713     if (!mayIgnoreSignedZero(N0))
3714       return SDValue();
3715 
3716     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3717     SDValue LHS = N0.getOperand(0);
3718     SDValue MHS = N0.getOperand(1);
3719     SDValue RHS = N0.getOperand(2);
3720 
3721     if (LHS.getOpcode() == ISD::FNEG)
3722       LHS = LHS.getOperand(0);
3723     else if (MHS.getOpcode() == ISD::FNEG)
3724       MHS = MHS.getOperand(0);
3725     else
3726       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3727 
3728     if (RHS.getOpcode() != ISD::FNEG)
3729       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3730     else
3731       RHS = RHS.getOperand(0);
3732 
3733     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3734     if (Res.getOpcode() != Opc)
3735       return SDValue(); // Op got folded away.
3736     if (!N0.hasOneUse())
3737       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3738     return Res;
3739   }
3740   case ISD::FMAXNUM:
3741   case ISD::FMINNUM:
3742   case ISD::FMAXNUM_IEEE:
3743   case ISD::FMINNUM_IEEE:
3744   case AMDGPUISD::FMAX_LEGACY:
3745   case AMDGPUISD::FMIN_LEGACY: {
3746     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3747     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3748     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3749     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3750 
3751     SDValue LHS = N0.getOperand(0);
3752     SDValue RHS = N0.getOperand(1);
3753 
3754     // 0 doesn't have a negated inline immediate.
3755     // TODO: This constant check should be generalized to other operations.
3756     if (isConstantCostlierToNegate(RHS))
3757       return SDValue();
3758 
3759     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3760     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3761     unsigned Opposite = inverseMinMax(Opc);
3762 
3763     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3764     if (Res.getOpcode() != Opposite)
3765       return SDValue(); // Op got folded away.
3766     if (!N0.hasOneUse())
3767       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3768     return Res;
3769   }
3770   case AMDGPUISD::FMED3: {
3771     SDValue Ops[3];
3772     for (unsigned I = 0; I < 3; ++I)
3773       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3774 
3775     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3776     if (Res.getOpcode() != AMDGPUISD::FMED3)
3777       return SDValue(); // Op got folded away.
3778     if (!N0.hasOneUse())
3779       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3780     return Res;
3781   }
3782   case ISD::FP_EXTEND:
3783   case ISD::FTRUNC:
3784   case ISD::FRINT:
3785   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3786   case ISD::FSIN:
3787   case ISD::FCANONICALIZE:
3788   case AMDGPUISD::RCP:
3789   case AMDGPUISD::RCP_LEGACY:
3790   case AMDGPUISD::RCP_IFLAG:
3791   case AMDGPUISD::SIN_HW: {
3792     SDValue CvtSrc = N0.getOperand(0);
3793     if (CvtSrc.getOpcode() == ISD::FNEG) {
3794       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3795       // (fneg (rcp (fneg x))) -> (rcp x)
3796       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3797     }
3798 
3799     if (!N0.hasOneUse())
3800       return SDValue();
3801 
3802     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3803     // (fneg (rcp x)) -> (rcp (fneg x))
3804     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3805     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3806   }
3807   case ISD::FP_ROUND: {
3808     SDValue CvtSrc = N0.getOperand(0);
3809 
3810     if (CvtSrc.getOpcode() == ISD::FNEG) {
3811       // (fneg (fp_round (fneg x))) -> (fp_round x)
3812       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3813                          CvtSrc.getOperand(0), N0.getOperand(1));
3814     }
3815 
3816     if (!N0.hasOneUse())
3817       return SDValue();
3818 
3819     // (fneg (fp_round x)) -> (fp_round (fneg x))
3820     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3821     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3822   }
3823   case ISD::FP16_TO_FP: {
3824     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3825     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3826     // Put the fneg back as a legal source operation that can be matched later.
3827     SDLoc SL(N);
3828 
3829     SDValue Src = N0.getOperand(0);
3830     EVT SrcVT = Src.getValueType();
3831 
3832     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3833     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3834                                   DAG.getConstant(0x8000, SL, SrcVT));
3835     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3836   }
3837   default:
3838     return SDValue();
3839   }
3840 }
3841 
3842 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3843                                                  DAGCombinerInfo &DCI) const {
3844   SelectionDAG &DAG = DCI.DAG;
3845   SDValue N0 = N->getOperand(0);
3846 
3847   if (!N0.hasOneUse())
3848     return SDValue();
3849 
3850   switch (N0.getOpcode()) {
3851   case ISD::FP16_TO_FP: {
3852     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3853     SDLoc SL(N);
3854     SDValue Src = N0.getOperand(0);
3855     EVT SrcVT = Src.getValueType();
3856 
3857     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3858     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3859                                   DAG.getConstant(0x7fff, SL, SrcVT));
3860     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3861   }
3862   default:
3863     return SDValue();
3864   }
3865 }
3866 
3867 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3868                                                 DAGCombinerInfo &DCI) const {
3869   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3870   if (!CFP)
3871     return SDValue();
3872 
3873   // XXX - Should this flush denormals?
3874   const APFloat &Val = CFP->getValueAPF();
3875   APFloat One(Val.getSemantics(), "1.0");
3876   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3877 }
3878 
3879 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3880                                                 DAGCombinerInfo &DCI) const {
3881   SelectionDAG &DAG = DCI.DAG;
3882   SDLoc DL(N);
3883 
3884   switch(N->getOpcode()) {
3885   default:
3886     break;
3887   case ISD::BITCAST: {
3888     EVT DestVT = N->getValueType(0);
3889 
3890     // Push casts through vector builds. This helps avoid emitting a large
3891     // number of copies when materializing floating point vector constants.
3892     //
3893     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3894     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3895     if (DestVT.isVector()) {
3896       SDValue Src = N->getOperand(0);
3897       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3898         EVT SrcVT = Src.getValueType();
3899         unsigned NElts = DestVT.getVectorNumElements();
3900 
3901         if (SrcVT.getVectorNumElements() == NElts) {
3902           EVT DestEltVT = DestVT.getVectorElementType();
3903 
3904           SmallVector<SDValue, 8> CastedElts;
3905           SDLoc SL(N);
3906           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3907             SDValue Elt = Src.getOperand(I);
3908             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3909           }
3910 
3911           return DAG.getBuildVector(DestVT, SL, CastedElts);
3912         }
3913       }
3914     }
3915 
3916     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3917       break;
3918 
3919     // Fold bitcasts of constants.
3920     //
3921     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3922     // TODO: Generalize and move to DAGCombiner
3923     SDValue Src = N->getOperand(0);
3924     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3925       if (Src.getValueType() == MVT::i64) {
3926         SDLoc SL(N);
3927         uint64_t CVal = C->getZExtValue();
3928         SDValue BV = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3929                                  DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3930                                  DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3931         return DAG.getNode(ISD::BITCAST, SL, DestVT, BV);
3932       }
3933     }
3934 
3935     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3936       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3937       SDLoc SL(N);
3938       uint64_t CVal = Val.getZExtValue();
3939       SDValue Vec = 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 
3943       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3944     }
3945 
3946     break;
3947   }
3948   case ISD::SHL: {
3949     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3950       break;
3951 
3952     return performShlCombine(N, DCI);
3953   }
3954   case ISD::SRL: {
3955     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3956       break;
3957 
3958     return performSrlCombine(N, DCI);
3959   }
3960   case ISD::SRA: {
3961     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3962       break;
3963 
3964     return performSraCombine(N, DCI);
3965   }
3966   case ISD::TRUNCATE:
3967     return performTruncateCombine(N, DCI);
3968   case ISD::MUL:
3969     return performMulCombine(N, DCI);
3970   case ISD::MULHS:
3971     return performMulhsCombine(N, DCI);
3972   case ISD::MULHU:
3973     return performMulhuCombine(N, DCI);
3974   case AMDGPUISD::MUL_I24:
3975   case AMDGPUISD::MUL_U24:
3976   case AMDGPUISD::MULHI_I24:
3977   case AMDGPUISD::MULHI_U24: {
3978     if (SDValue V = simplifyI24(N, DCI))
3979       return V;
3980     return SDValue();
3981   }
3982   case AMDGPUISD::MUL_LOHI_I24:
3983   case AMDGPUISD::MUL_LOHI_U24:
3984     return performMulLoHi24Combine(N, DCI);
3985   case ISD::SELECT:
3986     return performSelectCombine(N, DCI);
3987   case ISD::FNEG:
3988     return performFNegCombine(N, DCI);
3989   case ISD::FABS:
3990     return performFAbsCombine(N, DCI);
3991   case AMDGPUISD::BFE_I32:
3992   case AMDGPUISD::BFE_U32: {
3993     assert(!N->getValueType(0).isVector() &&
3994            "Vector handling of BFE not implemented");
3995     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
3996     if (!Width)
3997       break;
3998 
3999     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
4000     if (WidthVal == 0)
4001       return DAG.getConstant(0, DL, MVT::i32);
4002 
4003     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
4004     if (!Offset)
4005       break;
4006 
4007     SDValue BitsFrom = N->getOperand(0);
4008     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
4009 
4010     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
4011 
4012     if (OffsetVal == 0) {
4013       // This is already sign / zero extended, so try to fold away extra BFEs.
4014       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
4015 
4016       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
4017       if (OpSignBits >= SignBits)
4018         return BitsFrom;
4019 
4020       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
4021       if (Signed) {
4022         // This is a sign_extend_inreg. Replace it to take advantage of existing
4023         // DAG Combines. If not eliminated, we will match back to BFE during
4024         // selection.
4025 
4026         // TODO: The sext_inreg of extended types ends, although we can could
4027         // handle them in a single BFE.
4028         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
4029                            DAG.getValueType(SmallVT));
4030       }
4031 
4032       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
4033     }
4034 
4035     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
4036       if (Signed) {
4037         return constantFoldBFE<int32_t>(DAG,
4038                                         CVal->getSExtValue(),
4039                                         OffsetVal,
4040                                         WidthVal,
4041                                         DL);
4042       }
4043 
4044       return constantFoldBFE<uint32_t>(DAG,
4045                                        CVal->getZExtValue(),
4046                                        OffsetVal,
4047                                        WidthVal,
4048                                        DL);
4049     }
4050 
4051     if ((OffsetVal + WidthVal) >= 32 &&
4052         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
4053       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
4054       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
4055                          BitsFrom, ShiftVal);
4056     }
4057 
4058     if (BitsFrom.hasOneUse()) {
4059       APInt Demanded = APInt::getBitsSet(32,
4060                                          OffsetVal,
4061                                          OffsetVal + WidthVal);
4062 
4063       KnownBits Known;
4064       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
4065                                             !DCI.isBeforeLegalizeOps());
4066       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
4067       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
4068           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
4069         DCI.CommitTargetLoweringOpt(TLO);
4070       }
4071     }
4072 
4073     break;
4074   }
4075   case ISD::LOAD:
4076     return performLoadCombine(N, DCI);
4077   case ISD::STORE:
4078     return performStoreCombine(N, DCI);
4079   case AMDGPUISD::RCP:
4080   case AMDGPUISD::RCP_IFLAG:
4081     return performRcpCombine(N, DCI);
4082   case ISD::AssertZext:
4083   case ISD::AssertSext:
4084     return performAssertSZExtCombine(N, DCI);
4085   case ISD::INTRINSIC_WO_CHAIN:
4086     return performIntrinsicWOChainCombine(N, DCI);
4087   }
4088   return SDValue();
4089 }
4090 
4091 //===----------------------------------------------------------------------===//
4092 // Helper functions
4093 //===----------------------------------------------------------------------===//
4094 
4095 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
4096                                                    const TargetRegisterClass *RC,
4097                                                    unsigned Reg, EVT VT,
4098                                                    const SDLoc &SL,
4099                                                    bool RawReg) const {
4100   MachineFunction &MF = DAG.getMachineFunction();
4101   MachineRegisterInfo &MRI = MF.getRegInfo();
4102   unsigned VReg;
4103 
4104   if (!MRI.isLiveIn(Reg)) {
4105     VReg = MRI.createVirtualRegister(RC);
4106     MRI.addLiveIn(Reg, VReg);
4107   } else {
4108     VReg = MRI.getLiveInVirtReg(Reg);
4109   }
4110 
4111   if (RawReg)
4112     return DAG.getRegister(VReg, VT);
4113 
4114   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
4115 }
4116 
4117 // This may be called multiple times, and nothing prevents creating multiple
4118 // objects at the same offset. See if we already defined this object.
4119 static int getOrCreateFixedStackObject(MachineFrameInfo &MFI, unsigned Size,
4120                                        int64_t Offset) {
4121   for (int I = MFI.getObjectIndexBegin(); I < 0; ++I) {
4122     if (MFI.getObjectOffset(I) == Offset) {
4123       assert(MFI.getObjectSize(I) == Size);
4124       return I;
4125     }
4126   }
4127 
4128   return MFI.CreateFixedObject(Size, Offset, true);
4129 }
4130 
4131 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
4132                                                   EVT VT,
4133                                                   const SDLoc &SL,
4134                                                   int64_t Offset) const {
4135   MachineFunction &MF = DAG.getMachineFunction();
4136   MachineFrameInfo &MFI = MF.getFrameInfo();
4137   int FI = getOrCreateFixedStackObject(MFI, VT.getStoreSize(), Offset);
4138 
4139   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4140   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4141 
4142   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4143                      MachineMemOperand::MODereferenceable |
4144                      MachineMemOperand::MOInvariant);
4145 }
4146 
4147 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4148                                                    const SDLoc &SL,
4149                                                    SDValue Chain,
4150                                                    SDValue ArgVal,
4151                                                    int64_t Offset) const {
4152   MachineFunction &MF = DAG.getMachineFunction();
4153   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4154 
4155   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4156   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4157                                MachineMemOperand::MODereferenceable);
4158   return Store;
4159 }
4160 
4161 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4162                                              const TargetRegisterClass *RC,
4163                                              EVT VT, const SDLoc &SL,
4164                                              const ArgDescriptor &Arg) const {
4165   assert(Arg && "Attempting to load missing argument");
4166 
4167   SDValue V = Arg.isRegister() ?
4168     CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL) :
4169     loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4170 
4171   if (!Arg.isMasked())
4172     return V;
4173 
4174   unsigned Mask = Arg.getMask();
4175   unsigned Shift = countTrailingZeros<unsigned>(Mask);
4176   V = DAG.getNode(ISD::SRL, SL, VT, V,
4177                   DAG.getShiftAmountConstant(Shift, VT, SL));
4178   return DAG.getNode(ISD::AND, SL, VT, V,
4179                      DAG.getConstant(Mask >> Shift, SL, VT));
4180 }
4181 
4182 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4183     const MachineFunction &MF, const ImplicitParameter Param) const {
4184   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4185   const AMDGPUSubtarget &ST =
4186       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4187   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4188   const Align Alignment = ST.getAlignmentForImplicitArgPtr();
4189   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4190                        ExplicitArgOffset;
4191   switch (Param) {
4192   case GRID_DIM:
4193     return ArgOffset;
4194   case GRID_OFFSET:
4195     return ArgOffset + 4;
4196   }
4197   llvm_unreachable("unexpected implicit parameter type");
4198 }
4199 
4200 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4201 
4202 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4203   switch ((AMDGPUISD::NodeType)Opcode) {
4204   case AMDGPUISD::FIRST_NUMBER: break;
4205   // AMDIL DAG nodes
4206   NODE_NAME_CASE(UMUL);
4207   NODE_NAME_CASE(BRANCH_COND);
4208 
4209   // AMDGPU DAG nodes
4210   NODE_NAME_CASE(IF)
4211   NODE_NAME_CASE(ELSE)
4212   NODE_NAME_CASE(LOOP)
4213   NODE_NAME_CASE(CALL)
4214   NODE_NAME_CASE(TC_RETURN)
4215   NODE_NAME_CASE(TRAP)
4216   NODE_NAME_CASE(RET_FLAG)
4217   NODE_NAME_CASE(RETURN_TO_EPILOG)
4218   NODE_NAME_CASE(ENDPGM)
4219   NODE_NAME_CASE(DWORDADDR)
4220   NODE_NAME_CASE(FRACT)
4221   NODE_NAME_CASE(SETCC)
4222   NODE_NAME_CASE(SETREG)
4223   NODE_NAME_CASE(DENORM_MODE)
4224   NODE_NAME_CASE(FMA_W_CHAIN)
4225   NODE_NAME_CASE(FMUL_W_CHAIN)
4226   NODE_NAME_CASE(CLAMP)
4227   NODE_NAME_CASE(COS_HW)
4228   NODE_NAME_CASE(SIN_HW)
4229   NODE_NAME_CASE(FMAX_LEGACY)
4230   NODE_NAME_CASE(FMIN_LEGACY)
4231   NODE_NAME_CASE(FMAX3)
4232   NODE_NAME_CASE(SMAX3)
4233   NODE_NAME_CASE(UMAX3)
4234   NODE_NAME_CASE(FMIN3)
4235   NODE_NAME_CASE(SMIN3)
4236   NODE_NAME_CASE(UMIN3)
4237   NODE_NAME_CASE(FMED3)
4238   NODE_NAME_CASE(SMED3)
4239   NODE_NAME_CASE(UMED3)
4240   NODE_NAME_CASE(FDOT2)
4241   NODE_NAME_CASE(URECIP)
4242   NODE_NAME_CASE(DIV_SCALE)
4243   NODE_NAME_CASE(DIV_FMAS)
4244   NODE_NAME_CASE(DIV_FIXUP)
4245   NODE_NAME_CASE(FMAD_FTZ)
4246   NODE_NAME_CASE(TRIG_PREOP)
4247   NODE_NAME_CASE(RCP)
4248   NODE_NAME_CASE(RSQ)
4249   NODE_NAME_CASE(RCP_LEGACY)
4250   NODE_NAME_CASE(RSQ_LEGACY)
4251   NODE_NAME_CASE(RCP_IFLAG)
4252   NODE_NAME_CASE(FMUL_LEGACY)
4253   NODE_NAME_CASE(RSQ_CLAMP)
4254   NODE_NAME_CASE(LDEXP)
4255   NODE_NAME_CASE(FP_CLASS)
4256   NODE_NAME_CASE(DOT4)
4257   NODE_NAME_CASE(CARRY)
4258   NODE_NAME_CASE(BORROW)
4259   NODE_NAME_CASE(BFE_U32)
4260   NODE_NAME_CASE(BFE_I32)
4261   NODE_NAME_CASE(BFI)
4262   NODE_NAME_CASE(BFM)
4263   NODE_NAME_CASE(FFBH_U32)
4264   NODE_NAME_CASE(FFBH_I32)
4265   NODE_NAME_CASE(FFBL_B32)
4266   NODE_NAME_CASE(MUL_U24)
4267   NODE_NAME_CASE(MUL_I24)
4268   NODE_NAME_CASE(MULHI_U24)
4269   NODE_NAME_CASE(MULHI_I24)
4270   NODE_NAME_CASE(MUL_LOHI_U24)
4271   NODE_NAME_CASE(MUL_LOHI_I24)
4272   NODE_NAME_CASE(MAD_U24)
4273   NODE_NAME_CASE(MAD_I24)
4274   NODE_NAME_CASE(MAD_I64_I32)
4275   NODE_NAME_CASE(MAD_U64_U32)
4276   NODE_NAME_CASE(PERM)
4277   NODE_NAME_CASE(TEXTURE_FETCH)
4278   NODE_NAME_CASE(EXPORT)
4279   NODE_NAME_CASE(EXPORT_DONE)
4280   NODE_NAME_CASE(R600_EXPORT)
4281   NODE_NAME_CASE(CONST_ADDRESS)
4282   NODE_NAME_CASE(REGISTER_LOAD)
4283   NODE_NAME_CASE(REGISTER_STORE)
4284   NODE_NAME_CASE(SAMPLE)
4285   NODE_NAME_CASE(SAMPLEB)
4286   NODE_NAME_CASE(SAMPLED)
4287   NODE_NAME_CASE(SAMPLEL)
4288   NODE_NAME_CASE(CVT_F32_UBYTE0)
4289   NODE_NAME_CASE(CVT_F32_UBYTE1)
4290   NODE_NAME_CASE(CVT_F32_UBYTE2)
4291   NODE_NAME_CASE(CVT_F32_UBYTE3)
4292   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4293   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4294   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4295   NODE_NAME_CASE(CVT_PK_I16_I32)
4296   NODE_NAME_CASE(CVT_PK_U16_U32)
4297   NODE_NAME_CASE(FP_TO_FP16)
4298   NODE_NAME_CASE(FP16_ZEXT)
4299   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4300   NODE_NAME_CASE(CONST_DATA_PTR)
4301   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4302   NODE_NAME_CASE(LDS)
4303   NODE_NAME_CASE(KILL)
4304   NODE_NAME_CASE(DUMMY_CHAIN)
4305   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4306   NODE_NAME_CASE(INTERP_P1LL_F16)
4307   NODE_NAME_CASE(INTERP_P1LV_F16)
4308   NODE_NAME_CASE(INTERP_P2_F16)
4309   NODE_NAME_CASE(LOAD_D16_HI)
4310   NODE_NAME_CASE(LOAD_D16_LO)
4311   NODE_NAME_CASE(LOAD_D16_HI_I8)
4312   NODE_NAME_CASE(LOAD_D16_HI_U8)
4313   NODE_NAME_CASE(LOAD_D16_LO_I8)
4314   NODE_NAME_CASE(LOAD_D16_LO_U8)
4315   NODE_NAME_CASE(STORE_MSKOR)
4316   NODE_NAME_CASE(LOAD_CONSTANT)
4317   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4318   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4319   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4320   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4321   NODE_NAME_CASE(DS_ORDERED_COUNT)
4322   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4323   NODE_NAME_CASE(ATOMIC_INC)
4324   NODE_NAME_CASE(ATOMIC_DEC)
4325   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4326   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4327   NODE_NAME_CASE(BUFFER_LOAD)
4328   NODE_NAME_CASE(BUFFER_LOAD_UBYTE)
4329   NODE_NAME_CASE(BUFFER_LOAD_USHORT)
4330   NODE_NAME_CASE(BUFFER_LOAD_BYTE)
4331   NODE_NAME_CASE(BUFFER_LOAD_SHORT)
4332   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4333   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4334   NODE_NAME_CASE(SBUFFER_LOAD)
4335   NODE_NAME_CASE(BUFFER_STORE)
4336   NODE_NAME_CASE(BUFFER_STORE_BYTE)
4337   NODE_NAME_CASE(BUFFER_STORE_SHORT)
4338   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4339   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4340   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4341   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4342   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4343   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4344   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4345   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4346   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4347   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4348   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4349   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4350   NODE_NAME_CASE(BUFFER_ATOMIC_INC)
4351   NODE_NAME_CASE(BUFFER_ATOMIC_DEC)
4352   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4353   NODE_NAME_CASE(BUFFER_ATOMIC_FADD)
4354   NODE_NAME_CASE(BUFFER_ATOMIC_PK_FADD)
4355   NODE_NAME_CASE(ATOMIC_PK_FADD)
4356 
4357   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4358   }
4359   return nullptr;
4360 }
4361 
4362 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4363                                               SelectionDAG &DAG, int Enabled,
4364                                               int &RefinementSteps,
4365                                               bool &UseOneConstNR,
4366                                               bool Reciprocal) const {
4367   EVT VT = Operand.getValueType();
4368 
4369   if (VT == MVT::f32) {
4370     RefinementSteps = 0;
4371     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4372   }
4373 
4374   // TODO: There is also f64 rsq instruction, but the documentation is less
4375   // clear on its precision.
4376 
4377   return SDValue();
4378 }
4379 
4380 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4381                                                SelectionDAG &DAG, int Enabled,
4382                                                int &RefinementSteps) const {
4383   EVT VT = Operand.getValueType();
4384 
4385   if (VT == MVT::f32) {
4386     // Reciprocal, < 1 ulp error.
4387     //
4388     // This reciprocal approximation converges to < 0.5 ulp error with one
4389     // newton rhapson performed with two fused multiple adds (FMAs).
4390 
4391     RefinementSteps = 0;
4392     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4393   }
4394 
4395   // TODO: There is also f64 rcp instruction, but the documentation is less
4396   // clear on its precision.
4397 
4398   return SDValue();
4399 }
4400 
4401 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4402     const SDValue Op, KnownBits &Known,
4403     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4404 
4405   Known.resetAll(); // Don't know anything.
4406 
4407   unsigned Opc = Op.getOpcode();
4408 
4409   switch (Opc) {
4410   default:
4411     break;
4412   case AMDGPUISD::CARRY:
4413   case AMDGPUISD::BORROW: {
4414     Known.Zero = APInt::getHighBitsSet(32, 31);
4415     break;
4416   }
4417 
4418   case AMDGPUISD::BFE_I32:
4419   case AMDGPUISD::BFE_U32: {
4420     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4421     if (!CWidth)
4422       return;
4423 
4424     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4425 
4426     if (Opc == AMDGPUISD::BFE_U32)
4427       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4428 
4429     break;
4430   }
4431   case AMDGPUISD::FP_TO_FP16:
4432   case AMDGPUISD::FP16_ZEXT: {
4433     unsigned BitWidth = Known.getBitWidth();
4434 
4435     // High bits are zero.
4436     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4437     break;
4438   }
4439   case AMDGPUISD::MUL_U24:
4440   case AMDGPUISD::MUL_I24: {
4441     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4442     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4443     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4444                       RHSKnown.countMinTrailingZeros();
4445     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4446     // Skip extra check if all bits are known zeros.
4447     if (TrailZ >= 32)
4448       break;
4449 
4450     // Truncate to 24 bits.
4451     LHSKnown = LHSKnown.trunc(24);
4452     RHSKnown = RHSKnown.trunc(24);
4453 
4454     if (Opc == AMDGPUISD::MUL_I24) {
4455       unsigned LHSValBits = 24 - LHSKnown.countMinSignBits();
4456       unsigned RHSValBits = 24 - RHSKnown.countMinSignBits();
4457       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4458       if (MaxValBits >= 32)
4459         break;
4460       bool LHSNegative = LHSKnown.isNegative();
4461       bool LHSNonNegative = LHSKnown.isNonNegative();
4462       bool LHSPositive = LHSKnown.isStrictlyPositive();
4463       bool RHSNegative = RHSKnown.isNegative();
4464       bool RHSNonNegative = RHSKnown.isNonNegative();
4465       bool RHSPositive = RHSKnown.isStrictlyPositive();
4466 
4467       if ((LHSNonNegative && RHSNonNegative) || (LHSNegative && RHSNegative))
4468         Known.Zero.setHighBits(32 - MaxValBits);
4469       else if ((LHSNegative && RHSPositive) || (LHSPositive && RHSNegative))
4470         Known.One.setHighBits(32 - MaxValBits);
4471     } else {
4472       unsigned LHSValBits = 24 - LHSKnown.countMinLeadingZeros();
4473       unsigned RHSValBits = 24 - RHSKnown.countMinLeadingZeros();
4474       unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4475       if (MaxValBits >= 32)
4476         break;
4477       Known.Zero.setHighBits(32 - MaxValBits);
4478     }
4479     break;
4480   }
4481   case AMDGPUISD::PERM: {
4482     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4483     if (!CMask)
4484       return;
4485 
4486     KnownBits LHSKnown = DAG.computeKnownBits(Op.getOperand(0), Depth + 1);
4487     KnownBits RHSKnown = DAG.computeKnownBits(Op.getOperand(1), Depth + 1);
4488     unsigned Sel = CMask->getZExtValue();
4489 
4490     for (unsigned I = 0; I < 32; I += 8) {
4491       unsigned SelBits = Sel & 0xff;
4492       if (SelBits < 4) {
4493         SelBits *= 8;
4494         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4495         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4496       } else if (SelBits < 7) {
4497         SelBits = (SelBits & 3) * 8;
4498         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4499         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4500       } else if (SelBits == 0x0c) {
4501         Known.Zero |= 0xFFull << I;
4502       } else if (SelBits > 0x0c) {
4503         Known.One |= 0xFFull << I;
4504       }
4505       Sel >>= 8;
4506     }
4507     break;
4508   }
4509   case AMDGPUISD::BUFFER_LOAD_UBYTE:  {
4510     Known.Zero.setHighBits(24);
4511     break;
4512   }
4513   case AMDGPUISD::BUFFER_LOAD_USHORT: {
4514     Known.Zero.setHighBits(16);
4515     break;
4516   }
4517   case AMDGPUISD::LDS: {
4518     auto GA = cast<GlobalAddressSDNode>(Op.getOperand(0).getNode());
4519     unsigned Align = GA->getGlobal()->getAlignment();
4520 
4521     Known.Zero.setHighBits(16);
4522     if (Align)
4523       Known.Zero.setLowBits(Log2_32(Align));
4524     break;
4525   }
4526   case ISD::INTRINSIC_WO_CHAIN: {
4527     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4528     switch (IID) {
4529     case Intrinsic::amdgcn_mbcnt_lo:
4530     case Intrinsic::amdgcn_mbcnt_hi: {
4531       const GCNSubtarget &ST =
4532           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4533       // These return at most the wavefront size - 1.
4534       unsigned Size = Op.getValueType().getSizeInBits();
4535       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4536       break;
4537     }
4538     default:
4539       break;
4540     }
4541   }
4542   }
4543 }
4544 
4545 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4546     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4547     unsigned Depth) const {
4548   switch (Op.getOpcode()) {
4549   case AMDGPUISD::BFE_I32: {
4550     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4551     if (!Width)
4552       return 1;
4553 
4554     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4555     if (!isNullConstant(Op.getOperand(1)))
4556       return SignBits;
4557 
4558     // TODO: Could probably figure something out with non-0 offsets.
4559     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4560     return std::max(SignBits, Op0SignBits);
4561   }
4562 
4563   case AMDGPUISD::BFE_U32: {
4564     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4565     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4566   }
4567 
4568   case AMDGPUISD::CARRY:
4569   case AMDGPUISD::BORROW:
4570     return 31;
4571   case AMDGPUISD::BUFFER_LOAD_BYTE:
4572     return 25;
4573   case AMDGPUISD::BUFFER_LOAD_SHORT:
4574     return 17;
4575   case AMDGPUISD::BUFFER_LOAD_UBYTE:
4576     return 24;
4577   case AMDGPUISD::BUFFER_LOAD_USHORT:
4578     return 16;
4579   case AMDGPUISD::FP_TO_FP16:
4580   case AMDGPUISD::FP16_ZEXT:
4581     return 16;
4582   default:
4583     return 1;
4584   }
4585 }
4586 
4587 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4588                                                         const SelectionDAG &DAG,
4589                                                         bool SNaN,
4590                                                         unsigned Depth) const {
4591   unsigned Opcode = Op.getOpcode();
4592   switch (Opcode) {
4593   case AMDGPUISD::FMIN_LEGACY:
4594   case AMDGPUISD::FMAX_LEGACY: {
4595     if (SNaN)
4596       return true;
4597 
4598     // TODO: Can check no nans on one of the operands for each one, but which
4599     // one?
4600     return false;
4601   }
4602   case AMDGPUISD::FMUL_LEGACY:
4603   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4604     if (SNaN)
4605       return true;
4606     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4607            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4608   }
4609   case AMDGPUISD::FMED3:
4610   case AMDGPUISD::FMIN3:
4611   case AMDGPUISD::FMAX3:
4612   case AMDGPUISD::FMAD_FTZ: {
4613     if (SNaN)
4614       return true;
4615     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4616            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4617            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4618   }
4619   case AMDGPUISD::CVT_F32_UBYTE0:
4620   case AMDGPUISD::CVT_F32_UBYTE1:
4621   case AMDGPUISD::CVT_F32_UBYTE2:
4622   case AMDGPUISD::CVT_F32_UBYTE3:
4623     return true;
4624 
4625   case AMDGPUISD::RCP:
4626   case AMDGPUISD::RSQ:
4627   case AMDGPUISD::RCP_LEGACY:
4628   case AMDGPUISD::RSQ_LEGACY:
4629   case AMDGPUISD::RSQ_CLAMP: {
4630     if (SNaN)
4631       return true;
4632 
4633     // TODO: Need is known positive check.
4634     return false;
4635   }
4636   case AMDGPUISD::LDEXP:
4637   case AMDGPUISD::FRACT: {
4638     if (SNaN)
4639       return true;
4640     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4641   }
4642   case AMDGPUISD::DIV_SCALE:
4643   case AMDGPUISD::DIV_FMAS:
4644   case AMDGPUISD::DIV_FIXUP:
4645   case AMDGPUISD::TRIG_PREOP:
4646     // TODO: Refine on operands.
4647     return SNaN;
4648   case AMDGPUISD::SIN_HW:
4649   case AMDGPUISD::COS_HW: {
4650     // TODO: Need check for infinity
4651     return SNaN;
4652   }
4653   case ISD::INTRINSIC_WO_CHAIN: {
4654     unsigned IntrinsicID
4655       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4656     // TODO: Handle more intrinsics
4657     switch (IntrinsicID) {
4658     case Intrinsic::amdgcn_cubeid:
4659       return true;
4660 
4661     case Intrinsic::amdgcn_frexp_mant: {
4662       if (SNaN)
4663         return true;
4664       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4665     }
4666     case Intrinsic::amdgcn_cvt_pkrtz: {
4667       if (SNaN)
4668         return true;
4669       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4670              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4671     }
4672     case Intrinsic::amdgcn_fdot2:
4673       // TODO: Refine on operand
4674       return SNaN;
4675     default:
4676       return false;
4677     }
4678   }
4679   default:
4680     return false;
4681   }
4682 }
4683 
4684 TargetLowering::AtomicExpansionKind
4685 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4686   switch (RMW->getOperation()) {
4687   case AtomicRMWInst::Nand:
4688   case AtomicRMWInst::FAdd:
4689   case AtomicRMWInst::FSub:
4690     return AtomicExpansionKind::CmpXChg;
4691   default:
4692     return AtomicExpansionKind::None;
4693   }
4694 }
4695