1 //===-- AMDGPUISelLowering.cpp - AMDGPU Common DAG lowering functions -----===//
2 //
3 //                     The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 /// \file
11 /// This is the parent TargetLowering class for hardware code gen
12 /// targets.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #define AMDGPU_LOG2E_F     1.44269504088896340735992468100189214f
17 #define AMDGPU_LN2_F       0.693147180559945309417232121458176568f
18 #define AMDGPU_LN10_F      2.30258509299404568401799145468436421f
19 
20 #include "AMDGPUISelLowering.h"
21 #include "AMDGPU.h"
22 #include "AMDGPUCallLowering.h"
23 #include "AMDGPUFrameLowering.h"
24 #include "AMDGPUIntrinsicInfo.h"
25 #include "AMDGPURegisterInfo.h"
26 #include "AMDGPUSubtarget.h"
27 #include "AMDGPUTargetMachine.h"
28 #include "Utils/AMDGPUBaseInfo.h"
29 #include "R600MachineFunctionInfo.h"
30 #include "SIInstrInfo.h"
31 #include "SIMachineFunctionInfo.h"
32 #include "MCTargetDesc/AMDGPUMCTargetDesc.h"
33 #include "llvm/CodeGen/CallingConvLower.h"
34 #include "llvm/CodeGen/MachineFunction.h"
35 #include "llvm/CodeGen/MachineRegisterInfo.h"
36 #include "llvm/CodeGen/SelectionDAG.h"
37 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
38 #include "llvm/IR/DataLayout.h"
39 #include "llvm/IR/DiagnosticInfo.h"
40 #include "llvm/Support/KnownBits.h"
41 using namespace llvm;
42 
43 static bool allocateKernArg(unsigned ValNo, MVT ValVT, MVT LocVT,
44                             CCValAssign::LocInfo LocInfo,
45                             ISD::ArgFlagsTy ArgFlags, CCState &State) {
46   MachineFunction &MF = State.getMachineFunction();
47   AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
48 
49   uint64_t Offset = MFI->allocateKernArg(LocVT.getStoreSize(),
50                                          ArgFlags.getOrigAlign());
51   State.addLoc(CCValAssign::getCustomMem(ValNo, ValVT, Offset, LocVT, LocInfo));
52   return true;
53 }
54 
55 static bool allocateCCRegs(unsigned ValNo, MVT ValVT, MVT LocVT,
56                            CCValAssign::LocInfo LocInfo,
57                            ISD::ArgFlagsTy ArgFlags, CCState &State,
58                            const TargetRegisterClass *RC,
59                            unsigned NumRegs) {
60   ArrayRef<MCPhysReg> RegList = makeArrayRef(RC->begin(), NumRegs);
61   unsigned RegResult = State.AllocateReg(RegList);
62   if (RegResult == AMDGPU::NoRegister)
63     return false;
64 
65   State.addLoc(CCValAssign::getReg(ValNo, ValVT, RegResult, LocVT, LocInfo));
66   return true;
67 }
68 
69 static bool allocateSGPRTuple(unsigned ValNo, MVT ValVT, MVT LocVT,
70                               CCValAssign::LocInfo LocInfo,
71                               ISD::ArgFlagsTy ArgFlags, CCState &State) {
72   switch (LocVT.SimpleTy) {
73   case MVT::i64:
74   case MVT::f64:
75   case MVT::v2i32:
76   case MVT::v2f32: {
77     // Up to SGPR0-SGPR39
78     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
79                           &AMDGPU::SGPR_64RegClass, 20);
80   }
81   default:
82     return false;
83   }
84 }
85 
86 // Allocate up to VGPR31.
87 //
88 // TODO: Since there are no VGPR alignent requirements would it be better to
89 // split into individual scalar registers?
90 static bool allocateVGPRTuple(unsigned ValNo, MVT ValVT, MVT LocVT,
91                               CCValAssign::LocInfo LocInfo,
92                               ISD::ArgFlagsTy ArgFlags, CCState &State) {
93   switch (LocVT.SimpleTy) {
94   case MVT::i64:
95   case MVT::f64:
96   case MVT::v2i32:
97   case MVT::v2f32: {
98     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
99                           &AMDGPU::VReg_64RegClass, 31);
100   }
101   case MVT::v4i32:
102   case MVT::v4f32:
103   case MVT::v2i64:
104   case MVT::v2f64: {
105     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
106                           &AMDGPU::VReg_128RegClass, 29);
107   }
108   case MVT::v8i32:
109   case MVT::v8f32: {
110     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
111                           &AMDGPU::VReg_256RegClass, 25);
112 
113   }
114   case MVT::v16i32:
115   case MVT::v16f32: {
116     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
117                           &AMDGPU::VReg_512RegClass, 17);
118 
119   }
120   default:
121     return false;
122   }
123 }
124 
125 #include "AMDGPUGenCallingConv.inc"
126 
127 // Find a larger type to do a load / store of a vector with.
128 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
129   unsigned StoreSize = VT.getStoreSizeInBits();
130   if (StoreSize <= 32)
131     return EVT::getIntegerVT(Ctx, StoreSize);
132 
133   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
134   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
135 }
136 
137 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
138   KnownBits Known;
139   EVT VT = Op.getValueType();
140   DAG.computeKnownBits(Op, Known);
141 
142   return VT.getSizeInBits() - Known.countMinLeadingZeros();
143 }
144 
145 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
146   EVT VT = Op.getValueType();
147 
148   // In order for this to be a signed 24-bit value, bit 23, must
149   // be a sign bit.
150   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
151 }
152 
153 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
154                                            const AMDGPUSubtarget &STI)
155     : TargetLowering(TM), Subtarget(&STI) {
156   AMDGPUASI = AMDGPU::getAMDGPUAS(TM);
157   // Lower floating point store/load to integer store/load to reduce the number
158   // of patterns in tablegen.
159   setOperationAction(ISD::LOAD, MVT::f32, Promote);
160   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
161 
162   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
163   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
164 
165   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
166   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
167 
168   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
169   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
170 
171   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
172   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
173 
174   setOperationAction(ISD::LOAD, MVT::i64, Promote);
175   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
176 
177   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
178   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
179 
180   setOperationAction(ISD::LOAD, MVT::f64, Promote);
181   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
182 
183   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
184   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
185 
186   // There are no 64-bit extloads. These should be done as a 32-bit extload and
187   // an extension to 64-bit.
188   for (MVT VT : MVT::integer_valuetypes()) {
189     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
190     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
191     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
192   }
193 
194   for (MVT VT : MVT::integer_valuetypes()) {
195     if (VT == MVT::i64)
196       continue;
197 
198     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
199     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
200     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
201     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
202 
203     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
204     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
205     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
206     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
207 
208     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
209     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
210     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
211     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
212   }
213 
214   for (MVT VT : MVT::integer_vector_valuetypes()) {
215     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
216     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
217     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
218     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
219     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
220     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
221     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
222     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
223     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
224     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
225     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
226     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
227   }
228 
229   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
230   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
231   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
232   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
233 
234   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
235   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
236   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
237   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
238 
239   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
240   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
241   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
242   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
243 
244   setOperationAction(ISD::STORE, MVT::f32, Promote);
245   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
246 
247   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
248   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
249 
250   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
251   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
252 
253   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
254   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
255 
256   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
257   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
258 
259   setOperationAction(ISD::STORE, MVT::i64, Promote);
260   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
261 
262   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
263   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
264 
265   setOperationAction(ISD::STORE, MVT::f64, Promote);
266   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
267 
268   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
269   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
270 
271   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
272   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
273   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
274   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
275 
276   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
277   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
278   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
279   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
280 
281   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
282   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
283   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
284   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
285 
286   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
287   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
288 
289   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
290   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
291 
292   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
293   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
294 
295   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
296   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
297 
298 
299   setOperationAction(ISD::Constant, MVT::i32, Legal);
300   setOperationAction(ISD::Constant, MVT::i64, Legal);
301   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
302   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
303 
304   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
305   setOperationAction(ISD::BRIND, MVT::Other, Expand);
306 
307   // This is totally unsupported, just custom lower to produce an error.
308   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
309 
310   // Library functions.  These default to Expand, but we have instructions
311   // for them.
312   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
313   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
314   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
315   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
316   setOperationAction(ISD::FABS,   MVT::f32, Legal);
317   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
318   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
319   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
320   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
321   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
322 
323   setOperationAction(ISD::FROUND, MVT::f32, Custom);
324   setOperationAction(ISD::FROUND, MVT::f64, Custom);
325 
326   setOperationAction(ISD::FLOG, MVT::f32, Custom);
327   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
328 
329   if (Subtarget->has16BitInsts()) {
330     setOperationAction(ISD::FLOG, MVT::f16, Custom);
331     setOperationAction(ISD::FLOG10, MVT::f16, Custom);
332   }
333 
334   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
335   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
336 
337   setOperationAction(ISD::FREM, MVT::f32, Custom);
338   setOperationAction(ISD::FREM, MVT::f64, Custom);
339 
340   // v_mad_f32 does not support denormals according to some sources.
341   if (!Subtarget->hasFP32Denormals())
342     setOperationAction(ISD::FMAD, MVT::f32, Legal);
343 
344   // Expand to fneg + fadd.
345   setOperationAction(ISD::FSUB, MVT::f64, Expand);
346 
347   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
348   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
349   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
350   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
351   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
352   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
353   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
354   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
355   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
356   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
357 
358   if (Subtarget->getGeneration() < AMDGPUSubtarget::SEA_ISLANDS) {
359     setOperationAction(ISD::FCEIL, MVT::f64, Custom);
360     setOperationAction(ISD::FTRUNC, MVT::f64, Custom);
361     setOperationAction(ISD::FRINT, MVT::f64, Custom);
362     setOperationAction(ISD::FFLOOR, MVT::f64, Custom);
363   }
364 
365   if (!Subtarget->hasBFI()) {
366     // fcopysign can be done in a single instruction with BFI.
367     setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
368     setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
369   }
370 
371   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
372   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
373   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
374 
375   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
376   for (MVT VT : ScalarIntVTs) {
377     // These should use [SU]DIVREM, so set them to 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 
383     // GPU does not have divrem function for signed or unsigned.
384     setOperationAction(ISD::SDIVREM, VT, Custom);
385     setOperationAction(ISD::UDIVREM, VT, Custom);
386 
387     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
388     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
389     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
390 
391     setOperationAction(ISD::BSWAP, VT, Expand);
392     setOperationAction(ISD::CTTZ, VT, Expand);
393     setOperationAction(ISD::CTLZ, VT, Expand);
394   }
395 
396   if (!Subtarget->hasBCNT(32))
397     setOperationAction(ISD::CTPOP, MVT::i32, Expand);
398 
399   if (!Subtarget->hasBCNT(64))
400     setOperationAction(ISD::CTPOP, MVT::i64, Expand);
401 
402   // The hardware supports 32-bit ROTR, but not ROTL.
403   setOperationAction(ISD::ROTL, MVT::i32, Expand);
404   setOperationAction(ISD::ROTL, MVT::i64, Expand);
405   setOperationAction(ISD::ROTR, MVT::i64, Expand);
406 
407   setOperationAction(ISD::MUL, MVT::i64, Expand);
408   setOperationAction(ISD::MULHU, MVT::i64, Expand);
409   setOperationAction(ISD::MULHS, MVT::i64, Expand);
410   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
411   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
412   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
413   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
414   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
415 
416   setOperationAction(ISD::SMIN, MVT::i32, Legal);
417   setOperationAction(ISD::UMIN, MVT::i32, Legal);
418   setOperationAction(ISD::SMAX, MVT::i32, Legal);
419   setOperationAction(ISD::UMAX, MVT::i32, Legal);
420 
421   if (Subtarget->hasFFBH())
422     setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i32, Custom);
423 
424   if (Subtarget->hasFFBL())
425     setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i32, Custom);
426 
427   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
428   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
429   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
430   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
431 
432   // We only really have 32-bit BFE instructions (and 16-bit on VI).
433   //
434   // On SI+ there are 64-bit BFEs, but they are scalar only and there isn't any
435   // effort to match them now. We want this to be false for i64 cases when the
436   // extraction isn't restricted to the upper or lower half. Ideally we would
437   // have some pass reduce 64-bit extracts to 32-bit if possible. Extracts that
438   // span the midpoint are probably relatively rare, so don't worry about them
439   // for now.
440   if (Subtarget->hasBFE())
441     setHasExtractBitsInsn(true);
442 
443   static const MVT::SimpleValueType VectorIntTypes[] = {
444     MVT::v2i32, MVT::v4i32
445   };
446 
447   for (MVT VT : VectorIntTypes) {
448     // Expand the following operations for the current type by default.
449     setOperationAction(ISD::ADD,  VT, Expand);
450     setOperationAction(ISD::AND,  VT, Expand);
451     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
452     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
453     setOperationAction(ISD::MUL,  VT, Expand);
454     setOperationAction(ISD::MULHU, VT, Expand);
455     setOperationAction(ISD::MULHS, VT, Expand);
456     setOperationAction(ISD::OR,   VT, Expand);
457     setOperationAction(ISD::SHL,  VT, Expand);
458     setOperationAction(ISD::SRA,  VT, Expand);
459     setOperationAction(ISD::SRL,  VT, Expand);
460     setOperationAction(ISD::ROTL, VT, Expand);
461     setOperationAction(ISD::ROTR, VT, Expand);
462     setOperationAction(ISD::SUB,  VT, Expand);
463     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
464     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
465     setOperationAction(ISD::SDIV, VT, Expand);
466     setOperationAction(ISD::UDIV, VT, Expand);
467     setOperationAction(ISD::SREM, VT, Expand);
468     setOperationAction(ISD::UREM, VT, Expand);
469     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
470     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
471     setOperationAction(ISD::SDIVREM, VT, Custom);
472     setOperationAction(ISD::UDIVREM, VT, Expand);
473     setOperationAction(ISD::ADDC, VT, Expand);
474     setOperationAction(ISD::SUBC, VT, Expand);
475     setOperationAction(ISD::ADDE, VT, Expand);
476     setOperationAction(ISD::SUBE, VT, Expand);
477     setOperationAction(ISD::SELECT, VT, Expand);
478     setOperationAction(ISD::VSELECT, VT, Expand);
479     setOperationAction(ISD::SELECT_CC, VT, Expand);
480     setOperationAction(ISD::XOR,  VT, Expand);
481     setOperationAction(ISD::BSWAP, VT, Expand);
482     setOperationAction(ISD::CTPOP, VT, Expand);
483     setOperationAction(ISD::CTTZ, VT, Expand);
484     setOperationAction(ISD::CTLZ, VT, Expand);
485     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
486     setOperationAction(ISD::SETCC, VT, Expand);
487   }
488 
489   static const MVT::SimpleValueType FloatVectorTypes[] = {
490     MVT::v2f32, MVT::v4f32
491   };
492 
493   for (MVT VT : FloatVectorTypes) {
494     setOperationAction(ISD::FABS, VT, Expand);
495     setOperationAction(ISD::FMINNUM, VT, Expand);
496     setOperationAction(ISD::FMAXNUM, VT, Expand);
497     setOperationAction(ISD::FADD, VT, Expand);
498     setOperationAction(ISD::FCEIL, VT, Expand);
499     setOperationAction(ISD::FCOS, VT, Expand);
500     setOperationAction(ISD::FDIV, VT, Expand);
501     setOperationAction(ISD::FEXP2, VT, Expand);
502     setOperationAction(ISD::FLOG2, VT, Expand);
503     setOperationAction(ISD::FREM, VT, Expand);
504     setOperationAction(ISD::FLOG, VT, Expand);
505     setOperationAction(ISD::FLOG10, VT, Expand);
506     setOperationAction(ISD::FPOW, VT, Expand);
507     setOperationAction(ISD::FFLOOR, VT, Expand);
508     setOperationAction(ISD::FTRUNC, VT, Expand);
509     setOperationAction(ISD::FMUL, VT, Expand);
510     setOperationAction(ISD::FMA, VT, Expand);
511     setOperationAction(ISD::FRINT, VT, Expand);
512     setOperationAction(ISD::FNEARBYINT, VT, Expand);
513     setOperationAction(ISD::FSQRT, VT, Expand);
514     setOperationAction(ISD::FSIN, VT, Expand);
515     setOperationAction(ISD::FSUB, VT, Expand);
516     setOperationAction(ISD::FNEG, VT, Expand);
517     setOperationAction(ISD::VSELECT, VT, Expand);
518     setOperationAction(ISD::SELECT_CC, VT, Expand);
519     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
520     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
521     setOperationAction(ISD::SETCC, VT, Expand);
522   }
523 
524   // This causes using an unrolled select operation rather than expansion with
525   // bit operations. This is in general better, but the alternative using BFI
526   // instructions may be better if the select sources are SGPRs.
527   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
528   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
529 
530   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
531   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
532 
533   // There are no libcalls of any kind.
534   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
535     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
536 
537   setBooleanContents(ZeroOrNegativeOneBooleanContent);
538   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
539 
540   setSchedulingPreference(Sched::RegPressure);
541   setJumpIsExpensive(true);
542 
543   // FIXME: This is only partially true. If we have to do vector compares, any
544   // SGPR pair can be a condition register. If we have a uniform condition, we
545   // are better off doing SALU operations, where there is only one SCC. For now,
546   // we don't have a way of knowing during instruction selection if a condition
547   // will be uniform and we always use vector compares. Assume we are using
548   // vector compares until that is fixed.
549   setHasMultipleConditionRegisters(true);
550 
551   // SI at least has hardware support for floating point exceptions, but no way
552   // of using or handling them is implemented. They are also optional in OpenCL
553   // (Section 7.3)
554   setHasFloatingPointExceptions(Subtarget->hasFPExceptions());
555 
556   PredictableSelectIsExpensive = false;
557 
558   // We want to find all load dependencies for long chains of stores to enable
559   // merging into very wide vectors. The problem is with vectors with > 4
560   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
561   // vectors are a legal type, even though we have to split the loads
562   // usually. When we can more precisely specify load legality per address
563   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
564   // smarter so that they can figure out what to do in 2 iterations without all
565   // N > 4 stores on the same chain.
566   GatherAllAliasesMaxDepth = 16;
567 
568   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
569   // about these during lowering.
570   MaxStoresPerMemcpy  = 0xffffffff;
571   MaxStoresPerMemmove = 0xffffffff;
572   MaxStoresPerMemset  = 0xffffffff;
573 
574   setTargetDAGCombine(ISD::BITCAST);
575   setTargetDAGCombine(ISD::SHL);
576   setTargetDAGCombine(ISD::SRA);
577   setTargetDAGCombine(ISD::SRL);
578   setTargetDAGCombine(ISD::TRUNCATE);
579   setTargetDAGCombine(ISD::MUL);
580   setTargetDAGCombine(ISD::MULHU);
581   setTargetDAGCombine(ISD::MULHS);
582   setTargetDAGCombine(ISD::SELECT);
583   setTargetDAGCombine(ISD::SELECT_CC);
584   setTargetDAGCombine(ISD::STORE);
585   setTargetDAGCombine(ISD::FADD);
586   setTargetDAGCombine(ISD::FSUB);
587   setTargetDAGCombine(ISD::FNEG);
588   setTargetDAGCombine(ISD::FABS);
589   setTargetDAGCombine(ISD::AssertZext);
590   setTargetDAGCombine(ISD::AssertSext);
591 }
592 
593 //===----------------------------------------------------------------------===//
594 // Target Information
595 //===----------------------------------------------------------------------===//
596 
597 LLVM_READNONE
598 static bool fnegFoldsIntoOp(unsigned Opc) {
599   switch (Opc) {
600   case ISD::FADD:
601   case ISD::FSUB:
602   case ISD::FMUL:
603   case ISD::FMA:
604   case ISD::FMAD:
605   case ISD::FMINNUM:
606   case ISD::FMAXNUM:
607   case ISD::FSIN:
608   case ISD::FTRUNC:
609   case ISD::FRINT:
610   case ISD::FNEARBYINT:
611   case AMDGPUISD::RCP:
612   case AMDGPUISD::RCP_LEGACY:
613   case AMDGPUISD::SIN_HW:
614   case AMDGPUISD::FMUL_LEGACY:
615   case AMDGPUISD::FMIN_LEGACY:
616   case AMDGPUISD::FMAX_LEGACY:
617     return true;
618   default:
619     return false;
620   }
621 }
622 
623 /// \p returns true if the operation will definitely need to use a 64-bit
624 /// encoding, and thus will use a VOP3 encoding regardless of the source
625 /// modifiers.
626 LLVM_READONLY
627 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
628   return N->getNumOperands() > 2 || VT == MVT::f64;
629 }
630 
631 // Most FP instructions support source modifiers, but this could be refined
632 // slightly.
633 LLVM_READONLY
634 static bool hasSourceMods(const SDNode *N) {
635   if (isa<MemSDNode>(N))
636     return false;
637 
638   switch (N->getOpcode()) {
639   case ISD::CopyToReg:
640   case ISD::SELECT:
641   case ISD::FDIV:
642   case ISD::FREM:
643   case ISD::INLINEASM:
644   case AMDGPUISD::INTERP_P1:
645   case AMDGPUISD::INTERP_P2:
646   case AMDGPUISD::DIV_SCALE:
647 
648   // TODO: Should really be looking at the users of the bitcast. These are
649   // problematic because bitcasts are used to legalize all stores to integer
650   // types.
651   case ISD::BITCAST:
652     return false;
653   default:
654     return true;
655   }
656 }
657 
658 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
659                                                  unsigned CostThreshold) {
660   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
661   // it is truly free to use a source modifier in all cases. If there are
662   // multiple users but for each one will necessitate using VOP3, there will be
663   // a code size increase. Try to avoid increasing code size unless we know it
664   // will save on the instruction count.
665   unsigned NumMayIncreaseSize = 0;
666   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
667 
668   // XXX - Should this limit number of uses to check?
669   for (const SDNode *U : N->uses()) {
670     if (!hasSourceMods(U))
671       return false;
672 
673     if (!opMustUseVOP3Encoding(U, VT)) {
674       if (++NumMayIncreaseSize > CostThreshold)
675         return false;
676     }
677   }
678 
679   return true;
680 }
681 
682 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
683   return MVT::i32;
684 }
685 
686 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
687   return true;
688 }
689 
690 // The backend supports 32 and 64 bit floating point immediates.
691 // FIXME: Why are we reporting vectors of FP immediates as legal?
692 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
693   EVT ScalarVT = VT.getScalarType();
694   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
695          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
696 }
697 
698 // We don't want to shrink f64 / f32 constants.
699 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
700   EVT ScalarVT = VT.getScalarType();
701   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
702 }
703 
704 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
705                                                  ISD::LoadExtType,
706                                                  EVT NewVT) const {
707 
708   unsigned NewSize = NewVT.getStoreSizeInBits();
709 
710   // If we are reducing to a 32-bit load, this is always better.
711   if (NewSize == 32)
712     return true;
713 
714   EVT OldVT = N->getValueType(0);
715   unsigned OldSize = OldVT.getStoreSizeInBits();
716 
717   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
718   // extloads, so doing one requires using a buffer_load. In cases where we
719   // still couldn't use a scalar load, using the wider load shouldn't really
720   // hurt anything.
721 
722   // If the old size already had to be an extload, there's no harm in continuing
723   // to reduce the width.
724   return (OldSize < 32);
725 }
726 
727 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy,
728                                                    EVT CastTy) const {
729 
730   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
731 
732   if (LoadTy.getScalarType() == MVT::i32)
733     return false;
734 
735   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
736   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
737 
738   return (LScalarSize < CastScalarSize) ||
739          (CastScalarSize >= 32);
740 }
741 
742 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
743 // profitable with the expansion for 64-bit since it's generally good to
744 // speculate things.
745 // FIXME: These should really have the size as a parameter.
746 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
747   return true;
748 }
749 
750 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
751   return true;
752 }
753 
754 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
755   switch (N->getOpcode()) {
756     default:
757     return false;
758     case ISD::EntryToken:
759     case ISD::TokenFactor:
760       return true;
761     case ISD::INTRINSIC_WO_CHAIN:
762     {
763       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
764       switch (IntrID) {
765         default:
766         return false;
767         case Intrinsic::amdgcn_readfirstlane:
768         case Intrinsic::amdgcn_readlane:
769           return true;
770       }
771     }
772     break;
773     case ISD::LOAD:
774     {
775       const LoadSDNode * L = dyn_cast<LoadSDNode>(N);
776       if (L->getMemOperand()->getAddrSpace()
777       == Subtarget->getAMDGPUAS().CONSTANT_ADDRESS_32BIT)
778         return true;
779       return false;
780     }
781     break;
782   }
783 }
784 
785 bool AMDGPUTargetLowering::isSDNodeSourceOfDivergence(const SDNode * N,
786   FunctionLoweringInfo * FLI, DivergenceAnalysis * DA) const
787 {
788   switch (N->getOpcode()) {
789     case ISD::Register:
790     case ISD::CopyFromReg:
791     {
792       const RegisterSDNode *R = nullptr;
793       if (N->getOpcode() == ISD::Register) {
794         R = dyn_cast<RegisterSDNode>(N);
795       }
796       else {
797         R = dyn_cast<RegisterSDNode>(N->getOperand(1));
798       }
799       if (R)
800       {
801         const MachineFunction * MF = FLI->MF;
802         const SISubtarget &ST = MF->getSubtarget<SISubtarget>();
803         const MachineRegisterInfo &MRI = MF->getRegInfo();
804         const SIRegisterInfo &TRI = ST.getInstrInfo()->getRegisterInfo();
805         unsigned Reg = R->getReg();
806         if (TRI.isPhysicalRegister(Reg))
807           return TRI.isVGPR(MRI, Reg);
808 
809         if (MRI.isLiveIn(Reg)) {
810           // workitem.id.x workitem.id.y workitem.id.z
811           // Any VGPR formal argument is also considered divergent
812           if ((MRI.getLiveInPhysReg(Reg) == AMDGPU::T0_X) ||
813               (MRI.getLiveInPhysReg(Reg) == AMDGPU::T0_Y) ||
814               (MRI.getLiveInPhysReg(Reg) == AMDGPU::T0_Z) ||
815               (TRI.isVGPR(MRI, Reg)))
816               return true;
817           // Formal arguments of non-entry functions
818           // are conservatively considered divergent
819           else if (!AMDGPU::isEntryFunctionCC(FLI->Fn->getCallingConv()))
820             return true;
821         }
822         return !DA || DA->isDivergent(FLI->getValueFromVirtualReg(Reg));
823       }
824     }
825     break;
826     case ISD::LOAD: {
827       const LoadSDNode *L = dyn_cast<LoadSDNode>(N);
828       if (L->getMemOperand()->getAddrSpace() ==
829           Subtarget->getAMDGPUAS().PRIVATE_ADDRESS)
830         return true;
831     } break;
832     case ISD::CALLSEQ_END:
833     return true;
834     break;
835     case ISD::INTRINSIC_WO_CHAIN:
836     {
837 
838     }
839       return AMDGPU::isIntrinsicSourceOfDivergence(
840       cast<ConstantSDNode>(N->getOperand(0))->getZExtValue());
841     case ISD::INTRINSIC_W_CHAIN:
842       return AMDGPU::isIntrinsicSourceOfDivergence(
843       cast<ConstantSDNode>(N->getOperand(1))->getZExtValue());
844     // In some cases intrinsics that are a source of divergence have been
845     // lowered to AMDGPUISD so we also need to check those too.
846     case AMDGPUISD::INTERP_MOV:
847     case AMDGPUISD::INTERP_P1:
848     case AMDGPUISD::INTERP_P2:
849       return true;
850   }
851   return false;
852 }
853 
854 //===---------------------------------------------------------------------===//
855 // Target Properties
856 //===---------------------------------------------------------------------===//
857 
858 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
859   assert(VT.isFloatingPoint());
860 
861   // Packed operations do not have a fabs modifier.
862   return VT == MVT::f32 || VT == MVT::f64 ||
863          (Subtarget->has16BitInsts() && VT == MVT::f16);
864 }
865 
866 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
867   assert(VT.isFloatingPoint());
868   return VT == MVT::f32 || VT == MVT::f64 ||
869          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
870          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
871 }
872 
873 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
874                                                          unsigned NumElem,
875                                                          unsigned AS) const {
876   return true;
877 }
878 
879 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
880   // There are few operations which truly have vector input operands. Any vector
881   // operation is going to involve operations on each component, and a
882   // build_vector will be a copy per element, so it always makes sense to use a
883   // build_vector input in place of the extracted element to avoid a copy into a
884   // super register.
885   //
886   // We should probably only do this if all users are extracts only, but this
887   // should be the common case.
888   return true;
889 }
890 
891 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
892   // Truncate is just accessing a subregister.
893 
894   unsigned SrcSize = Source.getSizeInBits();
895   unsigned DestSize = Dest.getSizeInBits();
896 
897   return DestSize < SrcSize && DestSize % 32 == 0 ;
898 }
899 
900 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
901   // Truncate is just accessing a subregister.
902 
903   unsigned SrcSize = Source->getScalarSizeInBits();
904   unsigned DestSize = Dest->getScalarSizeInBits();
905 
906   if (DestSize== 16 && Subtarget->has16BitInsts())
907     return SrcSize >= 32;
908 
909   return DestSize < SrcSize && DestSize % 32 == 0;
910 }
911 
912 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
913   unsigned SrcSize = Src->getScalarSizeInBits();
914   unsigned DestSize = Dest->getScalarSizeInBits();
915 
916   if (SrcSize == 16 && Subtarget->has16BitInsts())
917     return DestSize >= 32;
918 
919   return SrcSize == 32 && DestSize == 64;
920 }
921 
922 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
923   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
924   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
925   // this will enable reducing 64-bit operations the 32-bit, which is always
926   // good.
927 
928   if (Src == MVT::i16)
929     return Dest == MVT::i32 ||Dest == MVT::i64 ;
930 
931   return Src == MVT::i32 && Dest == MVT::i64;
932 }
933 
934 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
935   return isZExtFree(Val.getValueType(), VT2);
936 }
937 
938 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
939   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
940   // limited number of native 64-bit operations. Shrinking an operation to fit
941   // in a single 32-bit register should always be helpful. As currently used,
942   // this is much less general than the name suggests, and is only used in
943   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
944   // not profitable, and may actually be harmful.
945   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
946 }
947 
948 //===---------------------------------------------------------------------===//
949 // TargetLowering Callbacks
950 //===---------------------------------------------------------------------===//
951 
952 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
953                                                   bool IsVarArg) {
954   switch (CC) {
955   case CallingConv::AMDGPU_KERNEL:
956   case CallingConv::SPIR_KERNEL:
957     return CC_AMDGPU_Kernel;
958   case CallingConv::AMDGPU_VS:
959   case CallingConv::AMDGPU_GS:
960   case CallingConv::AMDGPU_PS:
961   case CallingConv::AMDGPU_CS:
962   case CallingConv::AMDGPU_HS:
963   case CallingConv::AMDGPU_ES:
964   case CallingConv::AMDGPU_LS:
965     return CC_AMDGPU;
966   case CallingConv::C:
967   case CallingConv::Fast:
968   case CallingConv::Cold:
969     return CC_AMDGPU_Func;
970   default:
971     report_fatal_error("Unsupported calling convention.");
972   }
973 }
974 
975 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
976                                                     bool IsVarArg) {
977   switch (CC) {
978   case CallingConv::AMDGPU_KERNEL:
979   case CallingConv::SPIR_KERNEL:
980     return CC_AMDGPU_Kernel;
981   case CallingConv::AMDGPU_VS:
982   case CallingConv::AMDGPU_GS:
983   case CallingConv::AMDGPU_PS:
984   case CallingConv::AMDGPU_CS:
985   case CallingConv::AMDGPU_HS:
986   case CallingConv::AMDGPU_ES:
987   case CallingConv::AMDGPU_LS:
988     return RetCC_SI_Shader;
989   case CallingConv::C:
990   case CallingConv::Fast:
991   case CallingConv::Cold:
992     return RetCC_AMDGPU_Func;
993   default:
994     report_fatal_error("Unsupported calling convention.");
995   }
996 }
997 
998 /// The SelectionDAGBuilder will automatically promote function arguments
999 /// with illegal types.  However, this does not work for the AMDGPU targets
1000 /// since the function arguments are stored in memory as these illegal types.
1001 /// In order to handle this properly we need to get the original types sizes
1002 /// from the LLVM IR Function and fixup the ISD:InputArg values before
1003 /// passing them to AnalyzeFormalArguments()
1004 
1005 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
1006 /// input values across multiple registers.  Each item in the Ins array
1007 /// represents a single value that will be stored in registers.  Ins[x].VT is
1008 /// the value type of the value that will be stored in the register, so
1009 /// whatever SDNode we lower the argument to needs to be this type.
1010 ///
1011 /// In order to correctly lower the arguments we need to know the size of each
1012 /// argument.  Since Ins[x].VT gives us the size of the register that will
1013 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
1014 /// for the orignal function argument so that we can deduce the correct memory
1015 /// type to use for Ins[x].  In most cases the correct memory type will be
1016 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
1017 /// we have a kernel argument of type v8i8, this argument will be split into
1018 /// 8 parts and each part will be represented by its own item in the Ins array.
1019 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
1020 /// the argument before it was split.  From this, we deduce that the memory type
1021 /// for each individual part is i8.  We pass the memory type as LocVT to the
1022 /// calling convention analysis function and the register type (Ins[x].VT) as
1023 /// the ValVT.
1024 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(CCState &State,
1025                              const SmallVectorImpl<ISD::InputArg> &Ins) const {
1026   for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
1027     const ISD::InputArg &In = Ins[i];
1028     EVT MemVT;
1029 
1030     unsigned NumRegs = getNumRegisters(State.getContext(), In.ArgVT);
1031 
1032     if (!Subtarget->isAmdHsaOS() &&
1033         (In.ArgVT == MVT::i16 || In.ArgVT == MVT::i8 || In.ArgVT == MVT::f16)) {
1034       // The ABI says the caller will extend these values to 32-bits.
1035       MemVT = In.ArgVT.isInteger() ? MVT::i32 : MVT::f32;
1036     } else if (NumRegs == 1) {
1037       // This argument is not split, so the IR type is the memory type.
1038       assert(!In.Flags.isSplit());
1039       if (In.ArgVT.isExtended()) {
1040         // We have an extended type, like i24, so we should just use the register type
1041         MemVT = In.VT;
1042       } else {
1043         MemVT = In.ArgVT;
1044       }
1045     } else if (In.ArgVT.isVector() && In.VT.isVector() &&
1046                In.ArgVT.getScalarType() == In.VT.getScalarType()) {
1047       assert(In.ArgVT.getVectorNumElements() > In.VT.getVectorNumElements());
1048       // We have a vector value which has been split into a vector with
1049       // the same scalar type, but fewer elements.  This should handle
1050       // all the floating-point vector types.
1051       MemVT = In.VT;
1052     } else if (In.ArgVT.isVector() &&
1053                In.ArgVT.getVectorNumElements() == NumRegs) {
1054       // This arg has been split so that each element is stored in a separate
1055       // register.
1056       MemVT = In.ArgVT.getScalarType();
1057     } else if (In.ArgVT.isExtended()) {
1058       // We have an extended type, like i65.
1059       MemVT = In.VT;
1060     } else {
1061       unsigned MemoryBits = In.ArgVT.getStoreSizeInBits() / NumRegs;
1062       assert(In.ArgVT.getStoreSizeInBits() % NumRegs == 0);
1063       if (In.VT.isInteger()) {
1064         MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1065       } else if (In.VT.isVector()) {
1066         assert(!In.VT.getScalarType().isFloatingPoint());
1067         unsigned NumElements = In.VT.getVectorNumElements();
1068         assert(MemoryBits % NumElements == 0);
1069         // This vector type has been split into another vector type with
1070         // a different elements size.
1071         EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1072                                          MemoryBits / NumElements);
1073         MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1074       } else {
1075         llvm_unreachable("cannot deduce memory type.");
1076       }
1077     }
1078 
1079     // Convert one element vectors to scalar.
1080     if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1081       MemVT = MemVT.getScalarType();
1082 
1083     if (MemVT.isExtended()) {
1084       // This should really only happen if we have vec3 arguments
1085       assert(MemVT.isVector() && MemVT.getVectorNumElements() == 3);
1086       MemVT = MemVT.getPow2VectorType(State.getContext());
1087     }
1088 
1089     assert(MemVT.isSimple());
1090     allocateKernArg(i, In.VT, MemVT.getSimpleVT(), CCValAssign::Full, In.Flags,
1091                     State);
1092   }
1093 }
1094 
1095 SDValue AMDGPUTargetLowering::LowerReturn(
1096   SDValue Chain, CallingConv::ID CallConv,
1097   bool isVarArg,
1098   const SmallVectorImpl<ISD::OutputArg> &Outs,
1099   const SmallVectorImpl<SDValue> &OutVals,
1100   const SDLoc &DL, SelectionDAG &DAG) const {
1101   // FIXME: Fails for r600 tests
1102   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1103   // "wave terminate should not have return values");
1104   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1105 }
1106 
1107 //===---------------------------------------------------------------------===//
1108 // Target specific lowering
1109 //===---------------------------------------------------------------------===//
1110 
1111 /// Selects the correct CCAssignFn for a given CallingConvention value.
1112 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1113                                                     bool IsVarArg) {
1114   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1115 }
1116 
1117 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1118                                                       bool IsVarArg) {
1119   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1120 }
1121 
1122 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1123                                                   SelectionDAG &DAG,
1124                                                   MachineFrameInfo &MFI,
1125                                                   int ClobberedFI) const {
1126   SmallVector<SDValue, 8> ArgChains;
1127   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1128   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1129 
1130   // Include the original chain at the beginning of the list. When this is
1131   // used by target LowerCall hooks, this helps legalize find the
1132   // CALLSEQ_BEGIN node.
1133   ArgChains.push_back(Chain);
1134 
1135   // Add a chain value for each stack argument corresponding
1136   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1137                             UE = DAG.getEntryNode().getNode()->use_end();
1138        U != UE; ++U) {
1139     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1140       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1141         if (FI->getIndex() < 0) {
1142           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1143           int64_t InLastByte = InFirstByte;
1144           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1145 
1146           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1147               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1148             ArgChains.push_back(SDValue(L, 1));
1149         }
1150       }
1151     }
1152   }
1153 
1154   // Build a tokenfactor for all the chains.
1155   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1156 }
1157 
1158 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1159                                                  SmallVectorImpl<SDValue> &InVals,
1160                                                  StringRef Reason) const {
1161   SDValue Callee = CLI.Callee;
1162   SelectionDAG &DAG = CLI.DAG;
1163 
1164   const Function &Fn = DAG.getMachineFunction().getFunction();
1165 
1166   StringRef FuncName("<unknown>");
1167 
1168   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1169     FuncName = G->getSymbol();
1170   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1171     FuncName = G->getGlobal()->getName();
1172 
1173   DiagnosticInfoUnsupported NoCalls(
1174     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1175   DAG.getContext()->diagnose(NoCalls);
1176 
1177   if (!CLI.IsTailCall) {
1178     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1179       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1180   }
1181 
1182   return DAG.getEntryNode();
1183 }
1184 
1185 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1186                                         SmallVectorImpl<SDValue> &InVals) const {
1187   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1188 }
1189 
1190 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1191                                                       SelectionDAG &DAG) const {
1192   const Function &Fn = DAG.getMachineFunction().getFunction();
1193 
1194   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1195                                             SDLoc(Op).getDebugLoc());
1196   DAG.getContext()->diagnose(NoDynamicAlloca);
1197   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1198   return DAG.getMergeValues(Ops, SDLoc());
1199 }
1200 
1201 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1202                                              SelectionDAG &DAG) const {
1203   switch (Op.getOpcode()) {
1204   default:
1205     Op->print(errs(), &DAG);
1206     llvm_unreachable("Custom lowering code for this"
1207                      "instruction is not implemented yet!");
1208     break;
1209   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1210   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1211   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1212   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1213   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1214   case ISD::FREM: return LowerFREM(Op, DAG);
1215   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1216   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1217   case ISD::FRINT: return LowerFRINT(Op, DAG);
1218   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1219   case ISD::FROUND: return LowerFROUND(Op, DAG);
1220   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1221   case ISD::FLOG:
1222     return LowerFLOG(Op, DAG, 1 / AMDGPU_LOG2E_F);
1223   case ISD::FLOG10:
1224     return LowerFLOG(Op, DAG, AMDGPU_LN2_F / AMDGPU_LN10_F);
1225   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1226   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1227   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1228   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1229   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1230   case ISD::CTTZ:
1231   case ISD::CTTZ_ZERO_UNDEF:
1232   case ISD::CTLZ:
1233   case ISD::CTLZ_ZERO_UNDEF:
1234     return LowerCTLZ_CTTZ(Op, DAG);
1235   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1236   }
1237   return Op;
1238 }
1239 
1240 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1241                                               SmallVectorImpl<SDValue> &Results,
1242                                               SelectionDAG &DAG) const {
1243   switch (N->getOpcode()) {
1244   case ISD::SIGN_EXTEND_INREG:
1245     // Different parts of legalization seem to interpret which type of
1246     // sign_extend_inreg is the one to check for custom lowering. The extended
1247     // from type is what really matters, but some places check for custom
1248     // lowering of the result type. This results in trying to use
1249     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1250     // nothing here and let the illegal result integer be handled normally.
1251     return;
1252   default:
1253     return;
1254   }
1255 }
1256 
1257 static bool hasDefinedInitializer(const GlobalValue *GV) {
1258   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1259   if (!GVar || !GVar->hasInitializer())
1260     return false;
1261 
1262   return !isa<UndefValue>(GVar->getInitializer());
1263 }
1264 
1265 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1266                                                  SDValue Op,
1267                                                  SelectionDAG &DAG) const {
1268 
1269   const DataLayout &DL = DAG.getDataLayout();
1270   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1271   const GlobalValue *GV = G->getGlobal();
1272 
1273   if  (G->getAddressSpace() == AMDGPUASI.LOCAL_ADDRESS) {
1274     // XXX: What does the value of G->getOffset() mean?
1275     assert(G->getOffset() == 0 &&
1276          "Do not know what to do with an non-zero offset");
1277 
1278     // TODO: We could emit code to handle the initialization somewhere.
1279     if (!hasDefinedInitializer(GV)) {
1280       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1281       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1282     }
1283   }
1284 
1285   const Function &Fn = DAG.getMachineFunction().getFunction();
1286   DiagnosticInfoUnsupported BadInit(
1287       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1288   DAG.getContext()->diagnose(BadInit);
1289   return SDValue();
1290 }
1291 
1292 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1293                                                   SelectionDAG &DAG) const {
1294   SmallVector<SDValue, 8> Args;
1295 
1296   for (const SDUse &U : Op->ops())
1297     DAG.ExtractVectorElements(U.get(), Args);
1298 
1299   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1300 }
1301 
1302 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1303                                                      SelectionDAG &DAG) const {
1304 
1305   SmallVector<SDValue, 8> Args;
1306   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1307   EVT VT = Op.getValueType();
1308   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1309                             VT.getVectorNumElements());
1310 
1311   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1312 }
1313 
1314 /// Generate Min/Max node
1315 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1316                                                    SDValue LHS, SDValue RHS,
1317                                                    SDValue True, SDValue False,
1318                                                    SDValue CC,
1319                                                    DAGCombinerInfo &DCI) const {
1320   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1321     return SDValue();
1322 
1323   SelectionDAG &DAG = DCI.DAG;
1324   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1325   switch (CCOpcode) {
1326   case ISD::SETOEQ:
1327   case ISD::SETONE:
1328   case ISD::SETUNE:
1329   case ISD::SETNE:
1330   case ISD::SETUEQ:
1331   case ISD::SETEQ:
1332   case ISD::SETFALSE:
1333   case ISD::SETFALSE2:
1334   case ISD::SETTRUE:
1335   case ISD::SETTRUE2:
1336   case ISD::SETUO:
1337   case ISD::SETO:
1338     break;
1339   case ISD::SETULE:
1340   case ISD::SETULT: {
1341     if (LHS == True)
1342       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1343     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1344   }
1345   case ISD::SETOLE:
1346   case ISD::SETOLT:
1347   case ISD::SETLE:
1348   case ISD::SETLT: {
1349     // Ordered. Assume ordered for undefined.
1350 
1351     // Only do this after legalization to avoid interfering with other combines
1352     // which might occur.
1353     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1354         !DCI.isCalledByLegalizer())
1355       return SDValue();
1356 
1357     // We need to permute the operands to get the correct NaN behavior. The
1358     // selected operand is the second one based on the failing compare with NaN,
1359     // so permute it based on the compare type the hardware uses.
1360     if (LHS == True)
1361       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1362     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1363   }
1364   case ISD::SETUGE:
1365   case ISD::SETUGT: {
1366     if (LHS == True)
1367       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1368     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1369   }
1370   case ISD::SETGT:
1371   case ISD::SETGE:
1372   case ISD::SETOGE:
1373   case ISD::SETOGT: {
1374     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1375         !DCI.isCalledByLegalizer())
1376       return SDValue();
1377 
1378     if (LHS == True)
1379       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1380     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1381   }
1382   case ISD::SETCC_INVALID:
1383     llvm_unreachable("Invalid setcc condcode!");
1384   }
1385   return SDValue();
1386 }
1387 
1388 std::pair<SDValue, SDValue>
1389 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1390   SDLoc SL(Op);
1391 
1392   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1393 
1394   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1395   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1396 
1397   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1398   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1399 
1400   return std::make_pair(Lo, Hi);
1401 }
1402 
1403 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1404   SDLoc SL(Op);
1405 
1406   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1407   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1408   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1409 }
1410 
1411 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1412   SDLoc SL(Op);
1413 
1414   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1415   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1416   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1417 }
1418 
1419 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1420                                               SelectionDAG &DAG) const {
1421   LoadSDNode *Load = cast<LoadSDNode>(Op);
1422   EVT VT = Op.getValueType();
1423 
1424 
1425   // If this is a 2 element vector, we really want to scalarize and not create
1426   // weird 1 element vectors.
1427   if (VT.getVectorNumElements() == 2)
1428     return scalarizeVectorLoad(Load, DAG);
1429 
1430   SDValue BasePtr = Load->getBasePtr();
1431   EVT MemVT = Load->getMemoryVT();
1432   SDLoc SL(Op);
1433 
1434   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1435 
1436   EVT LoVT, HiVT;
1437   EVT LoMemVT, HiMemVT;
1438   SDValue Lo, Hi;
1439 
1440   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1441   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1442   std::tie(Lo, Hi) = DAG.SplitVector(Op, SL, LoVT, HiVT);
1443 
1444   unsigned Size = LoMemVT.getStoreSize();
1445   unsigned BaseAlign = Load->getAlignment();
1446   unsigned HiAlign = MinAlign(BaseAlign, Size);
1447 
1448   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1449                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1450                                   BaseAlign, Load->getMemOperand()->getFlags());
1451   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1452   SDValue HiLoad =
1453       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1454                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1455                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1456 
1457   SDValue Ops[] = {
1458     DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad),
1459     DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1460                 LoLoad.getValue(1), HiLoad.getValue(1))
1461   };
1462 
1463   return DAG.getMergeValues(Ops, SL);
1464 }
1465 
1466 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1467                                                SelectionDAG &DAG) const {
1468   StoreSDNode *Store = cast<StoreSDNode>(Op);
1469   SDValue Val = Store->getValue();
1470   EVT VT = Val.getValueType();
1471 
1472   // If this is a 2 element vector, we really want to scalarize and not create
1473   // weird 1 element vectors.
1474   if (VT.getVectorNumElements() == 2)
1475     return scalarizeVectorStore(Store, DAG);
1476 
1477   EVT MemVT = Store->getMemoryVT();
1478   SDValue Chain = Store->getChain();
1479   SDValue BasePtr = Store->getBasePtr();
1480   SDLoc SL(Op);
1481 
1482   EVT LoVT, HiVT;
1483   EVT LoMemVT, HiMemVT;
1484   SDValue Lo, Hi;
1485 
1486   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1487   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1488   std::tie(Lo, Hi) = DAG.SplitVector(Val, SL, LoVT, HiVT);
1489 
1490   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1491 
1492   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1493   unsigned BaseAlign = Store->getAlignment();
1494   unsigned Size = LoMemVT.getStoreSize();
1495   unsigned HiAlign = MinAlign(BaseAlign, Size);
1496 
1497   SDValue LoStore =
1498       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1499                         Store->getMemOperand()->getFlags());
1500   SDValue HiStore =
1501       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1502                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1503 
1504   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1505 }
1506 
1507 // This is a shortcut for integer division because we have fast i32<->f32
1508 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1509 // float is enough to accurately represent up to a 24-bit signed integer.
1510 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1511                                             bool Sign) const {
1512   SDLoc DL(Op);
1513   EVT VT = Op.getValueType();
1514   SDValue LHS = Op.getOperand(0);
1515   SDValue RHS = Op.getOperand(1);
1516   MVT IntVT = MVT::i32;
1517   MVT FltVT = MVT::f32;
1518 
1519   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1520   if (LHSSignBits < 9)
1521     return SDValue();
1522 
1523   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1524   if (RHSSignBits < 9)
1525     return SDValue();
1526 
1527   unsigned BitSize = VT.getSizeInBits();
1528   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1529   unsigned DivBits = BitSize - SignBits;
1530   if (Sign)
1531     ++DivBits;
1532 
1533   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1534   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1535 
1536   SDValue jq = DAG.getConstant(1, DL, IntVT);
1537 
1538   if (Sign) {
1539     // char|short jq = ia ^ ib;
1540     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1541 
1542     // jq = jq >> (bitsize - 2)
1543     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1544                      DAG.getConstant(BitSize - 2, DL, VT));
1545 
1546     // jq = jq | 0x1
1547     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1548   }
1549 
1550   // int ia = (int)LHS;
1551   SDValue ia = LHS;
1552 
1553   // int ib, (int)RHS;
1554   SDValue ib = RHS;
1555 
1556   // float fa = (float)ia;
1557   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1558 
1559   // float fb = (float)ib;
1560   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1561 
1562   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1563                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1564 
1565   // fq = trunc(fq);
1566   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1567 
1568   // float fqneg = -fq;
1569   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1570 
1571   // float fr = mad(fqneg, fb, fa);
1572   unsigned OpCode = Subtarget->hasFP32Denormals() ?
1573                     (unsigned)AMDGPUISD::FMAD_FTZ :
1574                     (unsigned)ISD::FMAD;
1575   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1576 
1577   // int iq = (int)fq;
1578   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1579 
1580   // fr = fabs(fr);
1581   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1582 
1583   // fb = fabs(fb);
1584   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1585 
1586   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1587 
1588   // int cv = fr >= fb;
1589   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1590 
1591   // jq = (cv ? jq : 0);
1592   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1593 
1594   // dst = iq + jq;
1595   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1596 
1597   // Rem needs compensation, it's easier to recompute it
1598   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1599   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1600 
1601   // Truncate to number of bits this divide really is.
1602   if (Sign) {
1603     SDValue InRegSize
1604       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1605     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1606     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1607   } else {
1608     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1609     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1610     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1611   }
1612 
1613   return DAG.getMergeValues({ Div, Rem }, DL);
1614 }
1615 
1616 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1617                                       SelectionDAG &DAG,
1618                                       SmallVectorImpl<SDValue> &Results) const {
1619   SDLoc DL(Op);
1620   EVT VT = Op.getValueType();
1621 
1622   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1623 
1624   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1625 
1626   SDValue One = DAG.getConstant(1, DL, HalfVT);
1627   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1628 
1629   //HiLo split
1630   SDValue LHS = Op.getOperand(0);
1631   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1632   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1633 
1634   SDValue RHS = Op.getOperand(1);
1635   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1636   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1637 
1638   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1639       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1640 
1641     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1642                               LHS_Lo, RHS_Lo);
1643 
1644     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1645     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1646 
1647     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1648     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1649     return;
1650   }
1651 
1652   if (isTypeLegal(MVT::i64)) {
1653     // Compute denominator reciprocal.
1654     unsigned FMAD = Subtarget->hasFP32Denormals() ?
1655                     (unsigned)AMDGPUISD::FMAD_FTZ :
1656                     (unsigned)ISD::FMAD;
1657 
1658     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1659     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1660     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1661       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1662       Cvt_Lo);
1663     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1664     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1665       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1666     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1667       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1668     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1669     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1670       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1671       Mul1);
1672     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1673     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1674     SDValue Rcp64 = DAG.getBitcast(VT,
1675                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1676 
1677     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1678     SDValue One64  = DAG.getConstant(1, DL, VT);
1679     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1680     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1681 
1682     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1683     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1684     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1685     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1686                                     Zero);
1687     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1688                                     One);
1689 
1690     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1691                                   Mulhi1_Lo, Zero1);
1692     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1693                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1694     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1695     SDValue Add1 = DAG.getBitcast(VT,
1696                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1697 
1698     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1699     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1700     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1701                                     Zero);
1702     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1703                                     One);
1704 
1705     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1706                                   Mulhi2_Lo, Zero1);
1707     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1708                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1709     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1710                                   Zero, Add2_Lo.getValue(1));
1711     SDValue Add2 = DAG.getBitcast(VT,
1712                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1713     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1714 
1715     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1716 
1717     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1718     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1719     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1720                                   Mul3_Lo, Zero1);
1721     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1722                                   Mul3_Hi, Sub1_Lo.getValue(1));
1723     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1724     SDValue Sub1 = DAG.getBitcast(VT,
1725                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1726 
1727     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1728     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1729                                  ISD::SETUGE);
1730     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1731                                  ISD::SETUGE);
1732     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1733 
1734     // TODO: Here and below portions of the code can be enclosed into if/endif.
1735     // Currently control flow is unconditional and we have 4 selects after
1736     // potential endif to substitute PHIs.
1737 
1738     // if C3 != 0 ...
1739     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1740                                   RHS_Lo, Zero1);
1741     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1742                                   RHS_Hi, Sub1_Lo.getValue(1));
1743     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1744                                   Zero, Sub2_Lo.getValue(1));
1745     SDValue Sub2 = DAG.getBitcast(VT,
1746                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1747 
1748     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1749 
1750     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1751                                  ISD::SETUGE);
1752     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1753                                  ISD::SETUGE);
1754     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1755 
1756     // if (C6 != 0)
1757     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1758 
1759     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1760                                   RHS_Lo, Zero1);
1761     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1762                                   RHS_Hi, Sub2_Lo.getValue(1));
1763     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1764                                   Zero, Sub3_Lo.getValue(1));
1765     SDValue Sub3 = DAG.getBitcast(VT,
1766                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1767 
1768     // endif C6
1769     // endif C3
1770 
1771     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1772     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1773 
1774     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1775     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1776 
1777     Results.push_back(Div);
1778     Results.push_back(Rem);
1779 
1780     return;
1781   }
1782 
1783   // r600 expandion.
1784   // Get Speculative values
1785   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1786   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1787 
1788   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1789   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1790   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1791 
1792   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1793   SDValue DIV_Lo = Zero;
1794 
1795   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1796 
1797   for (unsigned i = 0; i < halfBitWidth; ++i) {
1798     const unsigned bitPos = halfBitWidth - i - 1;
1799     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1800     // Get value of high bit
1801     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1802     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1803     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1804 
1805     // Shift
1806     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1807     // Add LHS high bit
1808     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1809 
1810     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1811     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1812 
1813     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1814 
1815     // Update REM
1816     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1817     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1818   }
1819 
1820   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1821   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1822   Results.push_back(DIV);
1823   Results.push_back(REM);
1824 }
1825 
1826 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1827                                            SelectionDAG &DAG) const {
1828   SDLoc DL(Op);
1829   EVT VT = Op.getValueType();
1830 
1831   if (VT == MVT::i64) {
1832     SmallVector<SDValue, 2> Results;
1833     LowerUDIVREM64(Op, DAG, Results);
1834     return DAG.getMergeValues(Results, DL);
1835   }
1836 
1837   if (VT == MVT::i32) {
1838     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1839       return Res;
1840   }
1841 
1842   SDValue Num = Op.getOperand(0);
1843   SDValue Den = Op.getOperand(1);
1844 
1845   // RCP =  URECIP(Den) = 2^32 / Den + e
1846   // e is rounding error.
1847   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1848 
1849   // RCP_LO = mul(RCP, Den) */
1850   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1851 
1852   // RCP_HI = mulhu (RCP, Den) */
1853   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1854 
1855   // NEG_RCP_LO = -RCP_LO
1856   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1857                                                      RCP_LO);
1858 
1859   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1860   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1861                                            NEG_RCP_LO, RCP_LO,
1862                                            ISD::SETEQ);
1863   // Calculate the rounding error from the URECIP instruction
1864   // E = mulhu(ABS_RCP_LO, RCP)
1865   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1866 
1867   // RCP_A_E = RCP + E
1868   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1869 
1870   // RCP_S_E = RCP - E
1871   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1872 
1873   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1874   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1875                                      RCP_A_E, RCP_S_E,
1876                                      ISD::SETEQ);
1877   // Quotient = mulhu(Tmp0, Num)
1878   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1879 
1880   // Num_S_Remainder = Quotient * Den
1881   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1882 
1883   // Remainder = Num - Num_S_Remainder
1884   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1885 
1886   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1887   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1888                                                  DAG.getConstant(-1, DL, VT),
1889                                                  DAG.getConstant(0, DL, VT),
1890                                                  ISD::SETUGE);
1891   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1892   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1893                                                   Num_S_Remainder,
1894                                                   DAG.getConstant(-1, DL, VT),
1895                                                   DAG.getConstant(0, DL, VT),
1896                                                   ISD::SETUGE);
1897   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1898   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1899                                                Remainder_GE_Zero);
1900 
1901   // Calculate Division result:
1902 
1903   // Quotient_A_One = Quotient + 1
1904   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1905                                        DAG.getConstant(1, DL, VT));
1906 
1907   // Quotient_S_One = Quotient - 1
1908   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1909                                        DAG.getConstant(1, DL, VT));
1910 
1911   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1912   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1913                                      Quotient, Quotient_A_One, ISD::SETEQ);
1914 
1915   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1916   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1917                             Quotient_S_One, Div, ISD::SETEQ);
1918 
1919   // Calculate Rem result:
1920 
1921   // Remainder_S_Den = Remainder - Den
1922   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1923 
1924   // Remainder_A_Den = Remainder + Den
1925   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1926 
1927   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1928   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1929                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1930 
1931   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1932   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1933                             Remainder_A_Den, Rem, ISD::SETEQ);
1934   SDValue Ops[2] = {
1935     Div,
1936     Rem
1937   };
1938   return DAG.getMergeValues(Ops, DL);
1939 }
1940 
1941 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
1942                                            SelectionDAG &DAG) const {
1943   SDLoc DL(Op);
1944   EVT VT = Op.getValueType();
1945 
1946   SDValue LHS = Op.getOperand(0);
1947   SDValue RHS = Op.getOperand(1);
1948 
1949   SDValue Zero = DAG.getConstant(0, DL, VT);
1950   SDValue NegOne = DAG.getConstant(-1, DL, VT);
1951 
1952   if (VT == MVT::i32) {
1953     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
1954       return Res;
1955   }
1956 
1957   if (VT == MVT::i64 &&
1958       DAG.ComputeNumSignBits(LHS) > 32 &&
1959       DAG.ComputeNumSignBits(RHS) > 32) {
1960     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1961 
1962     //HiLo split
1963     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1964     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1965     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1966                                  LHS_Lo, RHS_Lo);
1967     SDValue Res[2] = {
1968       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
1969       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
1970     };
1971     return DAG.getMergeValues(Res, DL);
1972   }
1973 
1974   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
1975   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
1976   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
1977   SDValue RSign = LHSign; // Remainder sign is the same as LHS
1978 
1979   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
1980   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
1981 
1982   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
1983   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
1984 
1985   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
1986   SDValue Rem = Div.getValue(1);
1987 
1988   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
1989   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
1990 
1991   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
1992   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
1993 
1994   SDValue Res[2] = {
1995     Div,
1996     Rem
1997   };
1998   return DAG.getMergeValues(Res, DL);
1999 }
2000 
2001 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
2002 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
2003   SDLoc SL(Op);
2004   EVT VT = Op.getValueType();
2005   SDValue X = Op.getOperand(0);
2006   SDValue Y = Op.getOperand(1);
2007 
2008   // TODO: Should this propagate fast-math-flags?
2009 
2010   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
2011   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
2012   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
2013 
2014   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
2015 }
2016 
2017 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
2018   SDLoc SL(Op);
2019   SDValue Src = Op.getOperand(0);
2020 
2021   // result = trunc(src)
2022   // if (src > 0.0 && src != result)
2023   //   result += 1.0
2024 
2025   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2026 
2027   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2028   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
2029 
2030   EVT SetCCVT =
2031       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2032 
2033   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
2034   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2035   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2036 
2037   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
2038   // TODO: Should this propagate fast-math-flags?
2039   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2040 }
2041 
2042 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
2043                                   SelectionDAG &DAG) {
2044   const unsigned FractBits = 52;
2045   const unsigned ExpBits = 11;
2046 
2047   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2048                                 Hi,
2049                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2050                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2051   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2052                             DAG.getConstant(1023, SL, MVT::i32));
2053 
2054   return Exp;
2055 }
2056 
2057 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2058   SDLoc SL(Op);
2059   SDValue Src = Op.getOperand(0);
2060 
2061   assert(Op.getValueType() == MVT::f64);
2062 
2063   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2064   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2065 
2066   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2067 
2068   // Extract the upper half, since this is where we will find the sign and
2069   // exponent.
2070   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2071 
2072   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2073 
2074   const unsigned FractBits = 52;
2075 
2076   // Extract the sign bit.
2077   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2078   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2079 
2080   // Extend back to 64-bits.
2081   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2082   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2083 
2084   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2085   const SDValue FractMask
2086     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2087 
2088   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2089   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2090   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2091 
2092   EVT SetCCVT =
2093       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2094 
2095   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2096 
2097   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2098   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2099 
2100   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2101   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2102 
2103   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2104 }
2105 
2106 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2107   SDLoc SL(Op);
2108   SDValue Src = Op.getOperand(0);
2109 
2110   assert(Op.getValueType() == MVT::f64);
2111 
2112   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2113   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2114   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2115 
2116   // TODO: Should this propagate fast-math-flags?
2117 
2118   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2119   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2120 
2121   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2122 
2123   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2124   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2125 
2126   EVT SetCCVT =
2127       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2128   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2129 
2130   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2131 }
2132 
2133 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2134   // FNEARBYINT and FRINT are the same, except in their handling of FP
2135   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2136   // rint, so just treat them as equivalent.
2137   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2138 }
2139 
2140 // XXX - May require not supporting f32 denormals?
2141 
2142 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2143 // compare and vselect end up producing worse code than scalarizing the whole
2144 // operation.
2145 SDValue AMDGPUTargetLowering::LowerFROUND32_16(SDValue Op, SelectionDAG &DAG) const {
2146   SDLoc SL(Op);
2147   SDValue X = Op.getOperand(0);
2148   EVT VT = Op.getValueType();
2149 
2150   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2151 
2152   // TODO: Should this propagate fast-math-flags?
2153 
2154   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2155 
2156   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2157 
2158   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2159   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2160   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2161 
2162   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2163 
2164   EVT SetCCVT =
2165       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2166 
2167   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2168 
2169   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2170 
2171   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2172 }
2173 
2174 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
2175   SDLoc SL(Op);
2176   SDValue X = Op.getOperand(0);
2177 
2178   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
2179 
2180   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2181   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2182   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
2183   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
2184   EVT SetCCVT =
2185       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2186 
2187   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
2188 
2189   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
2190 
2191   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2192 
2193   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
2194                                        MVT::i64);
2195 
2196   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
2197   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
2198                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
2199                                           MVT::i64),
2200                           Exp);
2201 
2202   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
2203   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
2204                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
2205                               ISD::SETNE);
2206 
2207   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
2208                              D, DAG.getConstant(0, SL, MVT::i64));
2209   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
2210 
2211   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
2212   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
2213 
2214   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2215   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2216   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
2217 
2218   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
2219                             ExpEqNegOne,
2220                             DAG.getConstantFP(1.0, SL, MVT::f64),
2221                             DAG.getConstantFP(0.0, SL, MVT::f64));
2222 
2223   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
2224 
2225   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
2226   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
2227 
2228   return K;
2229 }
2230 
2231 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2232   EVT VT = Op.getValueType();
2233 
2234   if (VT == MVT::f32 || VT == MVT::f16)
2235     return LowerFROUND32_16(Op, DAG);
2236 
2237   if (VT == MVT::f64)
2238     return LowerFROUND64(Op, DAG);
2239 
2240   llvm_unreachable("unhandled type");
2241 }
2242 
2243 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2244   SDLoc SL(Op);
2245   SDValue Src = Op.getOperand(0);
2246 
2247   // result = trunc(src);
2248   // if (src < 0.0 && src != result)
2249   //   result += -1.0.
2250 
2251   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2252 
2253   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2254   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2255 
2256   EVT SetCCVT =
2257       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2258 
2259   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2260   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2261   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2262 
2263   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2264   // TODO: Should this propagate fast-math-flags?
2265   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2266 }
2267 
2268 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2269                                         double Log2BaseInverted) const {
2270   EVT VT = Op.getValueType();
2271 
2272   SDLoc SL(Op);
2273   SDValue Operand = Op.getOperand(0);
2274   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2275   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2276 
2277   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2278 }
2279 
2280 static bool isCtlzOpc(unsigned Opc) {
2281   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2282 }
2283 
2284 static bool isCttzOpc(unsigned Opc) {
2285   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2286 }
2287 
2288 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2289   SDLoc SL(Op);
2290   SDValue Src = Op.getOperand(0);
2291   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2292                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2293 
2294   unsigned ISDOpc, NewOpc;
2295   if (isCtlzOpc(Op.getOpcode())) {
2296     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2297     NewOpc = AMDGPUISD::FFBH_U32;
2298   } else if (isCttzOpc(Op.getOpcode())) {
2299     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2300     NewOpc = AMDGPUISD::FFBL_B32;
2301   } else
2302     llvm_unreachable("Unexpected OPCode!!!");
2303 
2304 
2305   if (ZeroUndef && Src.getValueType() == MVT::i32)
2306     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2307 
2308   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2309 
2310   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2311   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2312 
2313   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2314   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2315 
2316   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2317                                    *DAG.getContext(), MVT::i32);
2318 
2319   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2320   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2321 
2322   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2323   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2324 
2325   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2326   SDValue Add, NewOpr;
2327   if (isCtlzOpc(Op.getOpcode())) {
2328     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2329     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2330     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2331   } else {
2332     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2333     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2334     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2335   }
2336 
2337   if (!ZeroUndef) {
2338     // Test if the full 64-bit input is zero.
2339 
2340     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2341     // which we probably don't want.
2342     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2343     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2344     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2345 
2346     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2347     // with the same cycles, otherwise it is slower.
2348     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2349     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2350 
2351     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2352 
2353     // The instruction returns -1 for 0 input, but the defined intrinsic
2354     // behavior is to return the number of bits.
2355     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2356                          SrcIsZero, Bits32, NewOpr);
2357   }
2358 
2359   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2360 }
2361 
2362 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2363                                                bool Signed) const {
2364   // Unsigned
2365   // cul2f(ulong u)
2366   //{
2367   //  uint lz = clz(u);
2368   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2369   //  u = (u << lz) & 0x7fffffffffffffffUL;
2370   //  ulong t = u & 0xffffffffffUL;
2371   //  uint v = (e << 23) | (uint)(u >> 40);
2372   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2373   //  return as_float(v + r);
2374   //}
2375   // Signed
2376   // cl2f(long l)
2377   //{
2378   //  long s = l >> 63;
2379   //  float r = cul2f((l + s) ^ s);
2380   //  return s ? -r : r;
2381   //}
2382 
2383   SDLoc SL(Op);
2384   SDValue Src = Op.getOperand(0);
2385   SDValue L = Src;
2386 
2387   SDValue S;
2388   if (Signed) {
2389     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2390     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2391 
2392     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2393     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2394   }
2395 
2396   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2397                                    *DAG.getContext(), MVT::f32);
2398 
2399 
2400   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2401   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2402   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2403   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2404 
2405   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2406   SDValue E = DAG.getSelect(SL, MVT::i32,
2407     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2408     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2409     ZeroI32);
2410 
2411   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2412     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2413     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2414 
2415   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2416                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2417 
2418   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2419                              U, DAG.getConstant(40, SL, MVT::i64));
2420 
2421   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2422     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2423     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2424 
2425   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2426   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2427   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2428 
2429   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2430 
2431   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2432 
2433   SDValue R = DAG.getSelect(SL, MVT::i32,
2434     RCmp,
2435     One,
2436     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2437   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2438   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2439 
2440   if (!Signed)
2441     return R;
2442 
2443   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2444   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2445 }
2446 
2447 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2448                                                bool Signed) const {
2449   SDLoc SL(Op);
2450   SDValue Src = Op.getOperand(0);
2451 
2452   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2453 
2454   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2455                            DAG.getConstant(0, SL, MVT::i32));
2456   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2457                            DAG.getConstant(1, SL, MVT::i32));
2458 
2459   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2460                               SL, MVT::f64, Hi);
2461 
2462   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2463 
2464   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2465                               DAG.getConstant(32, SL, MVT::i32));
2466   // TODO: Should this propagate fast-math-flags?
2467   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2468 }
2469 
2470 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2471                                                SelectionDAG &DAG) const {
2472   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2473          "operation should be legal");
2474 
2475   // TODO: Factor out code common with LowerSINT_TO_FP.
2476 
2477   EVT DestVT = Op.getValueType();
2478   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2479     SDLoc DL(Op);
2480     SDValue Src = Op.getOperand(0);
2481 
2482     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2483     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2484     SDValue FPRound =
2485         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2486 
2487     return FPRound;
2488   }
2489 
2490   if (DestVT == MVT::f32)
2491     return LowerINT_TO_FP32(Op, DAG, false);
2492 
2493   assert(DestVT == MVT::f64);
2494   return LowerINT_TO_FP64(Op, DAG, false);
2495 }
2496 
2497 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2498                                               SelectionDAG &DAG) const {
2499   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2500          "operation should be legal");
2501 
2502   // TODO: Factor out code common with LowerUINT_TO_FP.
2503 
2504   EVT DestVT = Op.getValueType();
2505   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2506     SDLoc DL(Op);
2507     SDValue Src = Op.getOperand(0);
2508 
2509     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2510     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2511     SDValue FPRound =
2512         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2513 
2514     return FPRound;
2515   }
2516 
2517   if (DestVT == MVT::f32)
2518     return LowerINT_TO_FP32(Op, DAG, true);
2519 
2520   assert(DestVT == MVT::f64);
2521   return LowerINT_TO_FP64(Op, DAG, true);
2522 }
2523 
2524 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2525                                                bool Signed) const {
2526   SDLoc SL(Op);
2527 
2528   SDValue Src = Op.getOperand(0);
2529 
2530   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2531 
2532   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2533                                  MVT::f64);
2534   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2535                                  MVT::f64);
2536   // TODO: Should this propagate fast-math-flags?
2537   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2538 
2539   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2540 
2541 
2542   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2543 
2544   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2545                            MVT::i32, FloorMul);
2546   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2547 
2548   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2549 
2550   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2551 }
2552 
2553 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2554   SDLoc DL(Op);
2555   SDValue N0 = Op.getOperand(0);
2556 
2557   // Convert to target node to get known bits
2558   if (N0.getValueType() == MVT::f32)
2559     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2560 
2561   if (getTargetMachine().Options.UnsafeFPMath) {
2562     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2563     return SDValue();
2564   }
2565 
2566   assert(N0.getSimpleValueType() == MVT::f64);
2567 
2568   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2569   const unsigned ExpMask = 0x7ff;
2570   const unsigned ExpBiasf64 = 1023;
2571   const unsigned ExpBiasf16 = 15;
2572   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2573   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2574   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2575   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2576                            DAG.getConstant(32, DL, MVT::i64));
2577   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2578   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2579   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2580                           DAG.getConstant(20, DL, MVT::i64));
2581   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2582                   DAG.getConstant(ExpMask, DL, MVT::i32));
2583   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2584   // add the f16 bias (15) to get the biased exponent for the f16 format.
2585   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2586                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2587 
2588   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2589                           DAG.getConstant(8, DL, MVT::i32));
2590   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2591                   DAG.getConstant(0xffe, DL, MVT::i32));
2592 
2593   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2594                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2595   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2596 
2597   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2598   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2599 
2600   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2601   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2602       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2603                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2604 
2605   // N = M | (E << 12);
2606   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2607       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2608                   DAG.getConstant(12, DL, MVT::i32)));
2609 
2610   // B = clamp(1-E, 0, 13);
2611   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2612                                   One, E);
2613   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2614   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2615                   DAG.getConstant(13, DL, MVT::i32));
2616 
2617   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2618                                    DAG.getConstant(0x1000, DL, MVT::i32));
2619 
2620   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2621   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2622   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2623   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2624 
2625   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2626   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2627                               DAG.getConstant(0x7, DL, MVT::i32));
2628   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2629                   DAG.getConstant(2, DL, MVT::i32));
2630   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2631                                One, Zero, ISD::SETEQ);
2632   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2633                                One, Zero, ISD::SETGT);
2634   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2635   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2636 
2637   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2638                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2639   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2640                       I, V, ISD::SETEQ);
2641 
2642   // Extract the sign bit.
2643   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2644                             DAG.getConstant(16, DL, MVT::i32));
2645   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2646                      DAG.getConstant(0x8000, DL, MVT::i32));
2647 
2648   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2649   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2650 }
2651 
2652 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2653                                               SelectionDAG &DAG) const {
2654   SDValue Src = Op.getOperand(0);
2655 
2656   // TODO: Factor out code common with LowerFP_TO_UINT.
2657 
2658   EVT SrcVT = Src.getValueType();
2659   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2660     SDLoc DL(Op);
2661 
2662     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2663     SDValue FpToInt32 =
2664         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2665 
2666     return FpToInt32;
2667   }
2668 
2669   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2670     return LowerFP64_TO_INT(Op, DAG, true);
2671 
2672   return SDValue();
2673 }
2674 
2675 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2676                                               SelectionDAG &DAG) const {
2677   SDValue Src = Op.getOperand(0);
2678 
2679   // TODO: Factor out code common with LowerFP_TO_SINT.
2680 
2681   EVT SrcVT = Src.getValueType();
2682   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2683     SDLoc DL(Op);
2684 
2685     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2686     SDValue FpToInt32 =
2687         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2688 
2689     return FpToInt32;
2690   }
2691 
2692   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2693     return LowerFP64_TO_INT(Op, DAG, false);
2694 
2695   return SDValue();
2696 }
2697 
2698 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2699                                                      SelectionDAG &DAG) const {
2700   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2701   MVT VT = Op.getSimpleValueType();
2702   MVT ScalarVT = VT.getScalarType();
2703 
2704   assert(VT.isVector());
2705 
2706   SDValue Src = Op.getOperand(0);
2707   SDLoc DL(Op);
2708 
2709   // TODO: Don't scalarize on Evergreen?
2710   unsigned NElts = VT.getVectorNumElements();
2711   SmallVector<SDValue, 8> Args;
2712   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2713 
2714   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2715   for (unsigned I = 0; I < NElts; ++I)
2716     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2717 
2718   return DAG.getBuildVector(VT, DL, Args);
2719 }
2720 
2721 //===----------------------------------------------------------------------===//
2722 // Custom DAG optimizations
2723 //===----------------------------------------------------------------------===//
2724 
2725 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2726   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2727 }
2728 
2729 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2730   EVT VT = Op.getValueType();
2731   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2732                                      // as unsigned 24-bit values.
2733     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2734 }
2735 
2736 static bool simplifyI24(SDNode *Node24, unsigned OpIdx,
2737                         TargetLowering::DAGCombinerInfo &DCI) {
2738 
2739   SelectionDAG &DAG = DCI.DAG;
2740   SDValue Op = Node24->getOperand(OpIdx);
2741   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2742   EVT VT = Op.getValueType();
2743 
2744   APInt Demanded = APInt::getLowBitsSet(VT.getSizeInBits(), 24);
2745   APInt KnownZero, KnownOne;
2746   TargetLowering::TargetLoweringOpt TLO(DAG, true, true);
2747   if (TLI.SimplifyDemandedBits(Node24, OpIdx, Demanded, DCI, TLO))
2748     return true;
2749 
2750   return false;
2751 }
2752 
2753 template <typename IntTy>
2754 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2755                                uint32_t Width, const SDLoc &DL) {
2756   if (Width + Offset < 32) {
2757     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2758     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2759     return DAG.getConstant(Result, DL, MVT::i32);
2760   }
2761 
2762   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2763 }
2764 
2765 static bool hasVolatileUser(SDNode *Val) {
2766   for (SDNode *U : Val->uses()) {
2767     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2768       if (M->isVolatile())
2769         return true;
2770     }
2771   }
2772 
2773   return false;
2774 }
2775 
2776 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2777   // i32 vectors are the canonical memory type.
2778   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2779     return false;
2780 
2781   if (!VT.isByteSized())
2782     return false;
2783 
2784   unsigned Size = VT.getStoreSize();
2785 
2786   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2787     return false;
2788 
2789   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2790     return false;
2791 
2792   return true;
2793 }
2794 
2795 // Replace load of an illegal type with a store of a bitcast to a friendlier
2796 // type.
2797 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2798                                                  DAGCombinerInfo &DCI) const {
2799   if (!DCI.isBeforeLegalize())
2800     return SDValue();
2801 
2802   LoadSDNode *LN = cast<LoadSDNode>(N);
2803   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2804     return SDValue();
2805 
2806   SDLoc SL(N);
2807   SelectionDAG &DAG = DCI.DAG;
2808   EVT VT = LN->getMemoryVT();
2809 
2810   unsigned Size = VT.getStoreSize();
2811   unsigned Align = LN->getAlignment();
2812   if (Align < Size && isTypeLegal(VT)) {
2813     bool IsFast;
2814     unsigned AS = LN->getAddressSpace();
2815 
2816     // Expand unaligned loads earlier than legalization. Due to visitation order
2817     // problems during legalization, the emitted instructions to pack and unpack
2818     // the bytes again are not eliminated in the case of an unaligned copy.
2819     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2820       if (VT.isVector())
2821         return scalarizeVectorLoad(LN, DAG);
2822 
2823       SDValue Ops[2];
2824       std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2825       return DAG.getMergeValues(Ops, SDLoc(N));
2826     }
2827 
2828     if (!IsFast)
2829       return SDValue();
2830   }
2831 
2832   if (!shouldCombineMemoryType(VT))
2833     return SDValue();
2834 
2835   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2836 
2837   SDValue NewLoad
2838     = DAG.getLoad(NewVT, SL, LN->getChain(),
2839                   LN->getBasePtr(), LN->getMemOperand());
2840 
2841   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2842   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2843   return SDValue(N, 0);
2844 }
2845 
2846 // Replace store of an illegal type with a store of a bitcast to a friendlier
2847 // type.
2848 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2849                                                   DAGCombinerInfo &DCI) const {
2850   if (!DCI.isBeforeLegalize())
2851     return SDValue();
2852 
2853   StoreSDNode *SN = cast<StoreSDNode>(N);
2854   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2855     return SDValue();
2856 
2857   EVT VT = SN->getMemoryVT();
2858   unsigned Size = VT.getStoreSize();
2859 
2860   SDLoc SL(N);
2861   SelectionDAG &DAG = DCI.DAG;
2862   unsigned Align = SN->getAlignment();
2863   if (Align < Size && isTypeLegal(VT)) {
2864     bool IsFast;
2865     unsigned AS = SN->getAddressSpace();
2866 
2867     // Expand unaligned stores earlier than legalization. Due to visitation
2868     // order problems during legalization, the emitted instructions to pack and
2869     // unpack the bytes again are not eliminated in the case of an unaligned
2870     // copy.
2871     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2872       if (VT.isVector())
2873         return scalarizeVectorStore(SN, DAG);
2874 
2875       return expandUnalignedStore(SN, DAG);
2876     }
2877 
2878     if (!IsFast)
2879       return SDValue();
2880   }
2881 
2882   if (!shouldCombineMemoryType(VT))
2883     return SDValue();
2884 
2885   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2886   SDValue Val = SN->getValue();
2887 
2888   //DCI.AddToWorklist(Val.getNode());
2889 
2890   bool OtherUses = !Val.hasOneUse();
2891   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2892   if (OtherUses) {
2893     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2894     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2895   }
2896 
2897   return DAG.getStore(SN->getChain(), SL, CastVal,
2898                       SN->getBasePtr(), SN->getMemOperand());
2899 }
2900 
2901 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2902 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2903 // issues.
2904 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2905                                                         DAGCombinerInfo &DCI) const {
2906   SelectionDAG &DAG = DCI.DAG;
2907   SDValue N0 = N->getOperand(0);
2908 
2909   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2910   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2911   if (N0.getOpcode() == ISD::TRUNCATE) {
2912     SDValue N1 = N->getOperand(1);
2913     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2914     SDLoc SL(N);
2915 
2916     SDValue Src = N0.getOperand(0);
2917     EVT SrcVT = Src.getValueType();
2918     if (SrcVT.bitsGE(ExtVT)) {
2919       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2920       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2921     }
2922   }
2923 
2924   return SDValue();
2925 }
2926 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
2927 /// binary operation \p Opc to it with the corresponding constant operands.
2928 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
2929   DAGCombinerInfo &DCI, const SDLoc &SL,
2930   unsigned Opc, SDValue LHS,
2931   uint32_t ValLo, uint32_t ValHi) const {
2932   SelectionDAG &DAG = DCI.DAG;
2933   SDValue Lo, Hi;
2934   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
2935 
2936   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
2937   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
2938 
2939   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
2940   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
2941 
2942   // Re-visit the ands. It's possible we eliminated one of them and it could
2943   // simplify the vector.
2944   DCI.AddToWorklist(Lo.getNode());
2945   DCI.AddToWorklist(Hi.getNode());
2946 
2947   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
2948   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2949 }
2950 
2951 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
2952                                                 DAGCombinerInfo &DCI) const {
2953   EVT VT = N->getValueType(0);
2954 
2955   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2956   if (!RHS)
2957     return SDValue();
2958 
2959   SDValue LHS = N->getOperand(0);
2960   unsigned RHSVal = RHS->getZExtValue();
2961   if (!RHSVal)
2962     return LHS;
2963 
2964   SDLoc SL(N);
2965   SelectionDAG &DAG = DCI.DAG;
2966 
2967   switch (LHS->getOpcode()) {
2968   default:
2969     break;
2970   case ISD::ZERO_EXTEND:
2971   case ISD::SIGN_EXTEND:
2972   case ISD::ANY_EXTEND: {
2973     SDValue X = LHS->getOperand(0);
2974 
2975     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
2976         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
2977       // Prefer build_vector as the canonical form if packed types are legal.
2978       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
2979       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
2980        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
2981       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
2982     }
2983 
2984     // shl (ext x) => zext (shl x), if shift does not overflow int
2985     if (VT != MVT::i64)
2986       break;
2987     KnownBits Known;
2988     DAG.computeKnownBits(X, Known);
2989     unsigned LZ = Known.countMinLeadingZeros();
2990     if (LZ < RHSVal)
2991       break;
2992     EVT XVT = X.getValueType();
2993     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
2994     return DAG.getZExtOrTrunc(Shl, SL, VT);
2995   }
2996   }
2997 
2998   if (VT != MVT::i64)
2999     return SDValue();
3000 
3001   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
3002 
3003   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
3004   // common case, splitting this into a move and a 32-bit shift is faster and
3005   // the same code size.
3006   if (RHSVal < 32)
3007     return SDValue();
3008 
3009   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
3010 
3011   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
3012   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
3013 
3014   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3015 
3016   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
3017   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
3018 }
3019 
3020 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
3021                                                 DAGCombinerInfo &DCI) const {
3022   if (N->getValueType(0) != MVT::i64)
3023     return SDValue();
3024 
3025   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3026   if (!RHS)
3027     return SDValue();
3028 
3029   SelectionDAG &DAG = DCI.DAG;
3030   SDLoc SL(N);
3031   unsigned RHSVal = RHS->getZExtValue();
3032 
3033   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3034   if (RHSVal == 32) {
3035     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3036     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3037                                    DAG.getConstant(31, SL, MVT::i32));
3038 
3039     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3040     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3041   }
3042 
3043   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3044   if (RHSVal == 63) {
3045     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3046     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3047                                    DAG.getConstant(31, SL, MVT::i32));
3048     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3049     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3050   }
3051 
3052   return SDValue();
3053 }
3054 
3055 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3056                                                 DAGCombinerInfo &DCI) const {
3057   if (N->getValueType(0) != MVT::i64)
3058     return SDValue();
3059 
3060   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3061   if (!RHS)
3062     return SDValue();
3063 
3064   unsigned ShiftAmt = RHS->getZExtValue();
3065   if (ShiftAmt < 32)
3066     return SDValue();
3067 
3068   // srl i64:x, C for C >= 32
3069   // =>
3070   //   build_pair (srl hi_32(x), C - 32), 0
3071 
3072   SelectionDAG &DAG = DCI.DAG;
3073   SDLoc SL(N);
3074 
3075   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3076   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3077 
3078   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, N->getOperand(0));
3079   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32,
3080                            VecOp, One);
3081 
3082   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3083   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3084 
3085   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3086 
3087   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3088 }
3089 
3090 SDValue AMDGPUTargetLowering::performTruncateCombine(
3091   SDNode *N, DAGCombinerInfo &DCI) const {
3092   SDLoc SL(N);
3093   SelectionDAG &DAG = DCI.DAG;
3094   EVT VT = N->getValueType(0);
3095   SDValue Src = N->getOperand(0);
3096 
3097   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3098   if (Src.getOpcode() == ISD::BITCAST) {
3099     SDValue Vec = Src.getOperand(0);
3100     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3101       SDValue Elt0 = Vec.getOperand(0);
3102       EVT EltVT = Elt0.getValueType();
3103       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3104         if (EltVT.isFloatingPoint()) {
3105           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3106                              EltVT.changeTypeToInteger(), Elt0);
3107         }
3108 
3109         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3110       }
3111     }
3112   }
3113 
3114   // Equivalent of above for accessing the high element of a vector as an
3115   // integer operation.
3116   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3117   if (Src.getOpcode() == ISD::SRL) {
3118     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3119       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3120         SDValue BV = stripBitcast(Src.getOperand(0));
3121         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3122             BV.getValueType().getVectorNumElements() == 2) {
3123           SDValue SrcElt = BV.getOperand(1);
3124           EVT SrcEltVT = SrcElt.getValueType();
3125           if (SrcEltVT.isFloatingPoint()) {
3126             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3127                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3128           }
3129 
3130           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3131         }
3132       }
3133     }
3134   }
3135 
3136   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3137   //
3138   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3139   //     i16 (trunc (srl (i32 (trunc x), K)))
3140   if (VT.getScalarSizeInBits() < 32) {
3141     EVT SrcVT = Src.getValueType();
3142     if (SrcVT.getScalarSizeInBits() > 32 &&
3143         (Src.getOpcode() == ISD::SRL ||
3144          Src.getOpcode() == ISD::SRA ||
3145          Src.getOpcode() == ISD::SHL)) {
3146       SDValue Amt = Src.getOperand(1);
3147       KnownBits Known;
3148       DAG.computeKnownBits(Amt, Known);
3149       unsigned Size = VT.getScalarSizeInBits();
3150       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3151           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3152         EVT MidVT = VT.isVector() ?
3153           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3154                            VT.getVectorNumElements()) : MVT::i32;
3155 
3156         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3157         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3158                                     Src.getOperand(0));
3159         DCI.AddToWorklist(Trunc.getNode());
3160 
3161         if (Amt.getValueType() != NewShiftVT) {
3162           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3163           DCI.AddToWorklist(Amt.getNode());
3164         }
3165 
3166         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3167                                           Trunc, Amt);
3168         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3169       }
3170     }
3171   }
3172 
3173   return SDValue();
3174 }
3175 
3176 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3177 // instructions. If we only match on the legalized i64 mul expansion,
3178 // SimplifyDemandedBits will be unable to remove them because there will be
3179 // multiple uses due to the separate mul + mulh[su].
3180 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3181                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3182   if (Size <= 32) {
3183     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3184     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3185   }
3186 
3187   // Because we want to eliminate extension instructions before the
3188   // operation, we need to create a single user here (i.e. not the separate
3189   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3190 
3191   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3192 
3193   SDValue Mul = DAG.getNode(MulOpc, SL,
3194                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3195 
3196   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3197                      Mul.getValue(0), Mul.getValue(1));
3198 }
3199 
3200 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3201                                                 DAGCombinerInfo &DCI) const {
3202   EVT VT = N->getValueType(0);
3203 
3204   unsigned Size = VT.getSizeInBits();
3205   if (VT.isVector() || Size > 64)
3206     return SDValue();
3207 
3208   // There are i16 integer mul/mad.
3209   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3210     return SDValue();
3211 
3212   SelectionDAG &DAG = DCI.DAG;
3213   SDLoc DL(N);
3214 
3215   SDValue N0 = N->getOperand(0);
3216   SDValue N1 = N->getOperand(1);
3217 
3218   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3219   // in the source into any_extends if the result of the mul is truncated. Since
3220   // we can assume the high bits are whatever we want, use the underlying value
3221   // to avoid the unknown high bits from interfering.
3222   if (N0.getOpcode() == ISD::ANY_EXTEND)
3223     N0 = N0.getOperand(0);
3224 
3225   if (N1.getOpcode() == ISD::ANY_EXTEND)
3226     N1 = N1.getOperand(0);
3227 
3228   SDValue Mul;
3229 
3230   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3231     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3232     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3233     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3234   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3235     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3236     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3237     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3238   } else {
3239     return SDValue();
3240   }
3241 
3242   // We need to use sext even for MUL_U24, because MUL_U24 is used
3243   // for signed multiply of 8 and 16-bit types.
3244   return DAG.getSExtOrTrunc(Mul, DL, VT);
3245 }
3246 
3247 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3248                                                   DAGCombinerInfo &DCI) const {
3249   EVT VT = N->getValueType(0);
3250 
3251   if (!Subtarget->hasMulI24() || VT.isVector())
3252     return SDValue();
3253 
3254   SelectionDAG &DAG = DCI.DAG;
3255   SDLoc DL(N);
3256 
3257   SDValue N0 = N->getOperand(0);
3258   SDValue N1 = N->getOperand(1);
3259 
3260   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3261     return SDValue();
3262 
3263   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3264   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3265 
3266   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3267   DCI.AddToWorklist(Mulhi.getNode());
3268   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3269 }
3270 
3271 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3272                                                   DAGCombinerInfo &DCI) const {
3273   EVT VT = N->getValueType(0);
3274 
3275   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3276     return SDValue();
3277 
3278   SelectionDAG &DAG = DCI.DAG;
3279   SDLoc DL(N);
3280 
3281   SDValue N0 = N->getOperand(0);
3282   SDValue N1 = N->getOperand(1);
3283 
3284   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3285     return SDValue();
3286 
3287   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3288   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3289 
3290   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3291   DCI.AddToWorklist(Mulhi.getNode());
3292   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3293 }
3294 
3295 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3296   SDNode *N, DAGCombinerInfo &DCI) const {
3297   SelectionDAG &DAG = DCI.DAG;
3298 
3299   // Simplify demanded bits before splitting into multiple users.
3300   if (simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI))
3301     return SDValue();
3302 
3303   SDValue N0 = N->getOperand(0);
3304   SDValue N1 = N->getOperand(1);
3305 
3306   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3307 
3308   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3309   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3310 
3311   SDLoc SL(N);
3312 
3313   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3314   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3315   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3316 }
3317 
3318 static bool isNegativeOne(SDValue Val) {
3319   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3320     return C->isAllOnesValue();
3321   return false;
3322 }
3323 
3324 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3325                                           SDValue Op,
3326                                           const SDLoc &DL,
3327                                           unsigned Opc) const {
3328   EVT VT = Op.getValueType();
3329   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3330   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3331                               LegalVT != MVT::i16))
3332     return SDValue();
3333 
3334   if (VT != MVT::i32)
3335     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3336 
3337   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3338   if (VT != MVT::i32)
3339     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3340 
3341   return FFBX;
3342 }
3343 
3344 // The native instructions return -1 on 0 input. Optimize out a select that
3345 // produces -1 on 0.
3346 //
3347 // TODO: If zero is not undef, we could also do this if the output is compared
3348 // against the bitwidth.
3349 //
3350 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3351 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3352                                                  SDValue LHS, SDValue RHS,
3353                                                  DAGCombinerInfo &DCI) const {
3354   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3355   if (!CmpRhs || !CmpRhs->isNullValue())
3356     return SDValue();
3357 
3358   SelectionDAG &DAG = DCI.DAG;
3359   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3360   SDValue CmpLHS = Cond.getOperand(0);
3361 
3362   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3363                                            AMDGPUISD::FFBH_U32;
3364 
3365   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3366   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3367   if (CCOpcode == ISD::SETEQ &&
3368       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3369       RHS.getOperand(0) == CmpLHS &&
3370       isNegativeOne(LHS)) {
3371     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3372   }
3373 
3374   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3375   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3376   if (CCOpcode == ISD::SETNE &&
3377       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3378       LHS.getOperand(0) == CmpLHS &&
3379       isNegativeOne(RHS)) {
3380     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3381   }
3382 
3383   return SDValue();
3384 }
3385 
3386 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3387                                          unsigned Op,
3388                                          const SDLoc &SL,
3389                                          SDValue Cond,
3390                                          SDValue N1,
3391                                          SDValue N2) {
3392   SelectionDAG &DAG = DCI.DAG;
3393   EVT VT = N1.getValueType();
3394 
3395   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3396                                   N1.getOperand(0), N2.getOperand(0));
3397   DCI.AddToWorklist(NewSelect.getNode());
3398   return DAG.getNode(Op, SL, VT, NewSelect);
3399 }
3400 
3401 // Pull a free FP operation out of a select so it may fold into uses.
3402 //
3403 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3404 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3405 //
3406 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3407 // select c, (fabs x), +k -> fabs (select c, x, k)
3408 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3409                                     SDValue N) {
3410   SelectionDAG &DAG = DCI.DAG;
3411   SDValue Cond = N.getOperand(0);
3412   SDValue LHS = N.getOperand(1);
3413   SDValue RHS = N.getOperand(2);
3414 
3415   EVT VT = N.getValueType();
3416   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3417       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3418     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3419                                      SDLoc(N), Cond, LHS, RHS);
3420   }
3421 
3422   bool Inv = false;
3423   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3424     std::swap(LHS, RHS);
3425     Inv = true;
3426   }
3427 
3428   // TODO: Support vector constants.
3429   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3430   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3431     SDLoc SL(N);
3432     // If one side is an fneg/fabs and the other is a constant, we can push the
3433     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3434     SDValue NewLHS = LHS.getOperand(0);
3435     SDValue NewRHS = RHS;
3436 
3437     // Careful: if the neg can be folded up, don't try to pull it back down.
3438     bool ShouldFoldNeg = true;
3439 
3440     if (NewLHS.hasOneUse()) {
3441       unsigned Opc = NewLHS.getOpcode();
3442       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3443         ShouldFoldNeg = false;
3444       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3445         ShouldFoldNeg = false;
3446     }
3447 
3448     if (ShouldFoldNeg) {
3449       if (LHS.getOpcode() == ISD::FNEG)
3450         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3451       else if (CRHS->isNegative())
3452         return SDValue();
3453 
3454       if (Inv)
3455         std::swap(NewLHS, NewRHS);
3456 
3457       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3458                                       Cond, NewLHS, NewRHS);
3459       DCI.AddToWorklist(NewSelect.getNode());
3460       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3461     }
3462   }
3463 
3464   return SDValue();
3465 }
3466 
3467 
3468 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3469                                                    DAGCombinerInfo &DCI) const {
3470   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3471     return Folded;
3472 
3473   SDValue Cond = N->getOperand(0);
3474   if (Cond.getOpcode() != ISD::SETCC)
3475     return SDValue();
3476 
3477   EVT VT = N->getValueType(0);
3478   SDValue LHS = Cond.getOperand(0);
3479   SDValue RHS = Cond.getOperand(1);
3480   SDValue CC = Cond.getOperand(2);
3481 
3482   SDValue True = N->getOperand(1);
3483   SDValue False = N->getOperand(2);
3484 
3485   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3486     SelectionDAG &DAG = DCI.DAG;
3487     if ((DAG.isConstantValueOfAnyType(True) ||
3488          DAG.isConstantValueOfAnyType(True)) &&
3489         (!DAG.isConstantValueOfAnyType(False) &&
3490          !DAG.isConstantValueOfAnyType(False))) {
3491       // Swap cmp + select pair to move constant to false input.
3492       // This will allow using VOPC cndmasks more often.
3493       // select (setcc x, y), k, x -> select (setcc y, x) x, x
3494 
3495       SDLoc SL(N);
3496       ISD::CondCode NewCC = getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
3497                                             LHS.getValueType().isInteger());
3498 
3499       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3500       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3501     }
3502 
3503     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3504       SDValue MinMax
3505         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3506       // Revisit this node so we can catch min3/max3/med3 patterns.
3507       //DCI.AddToWorklist(MinMax.getNode());
3508       return MinMax;
3509     }
3510   }
3511 
3512   // There's no reason to not do this if the condition has other uses.
3513   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3514 }
3515 
3516 static bool isConstantFPZero(SDValue N) {
3517   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N))
3518     return C->isZero() && !C->isNegative();
3519   return false;
3520 }
3521 
3522 static unsigned inverseMinMax(unsigned Opc) {
3523   switch (Opc) {
3524   case ISD::FMAXNUM:
3525     return ISD::FMINNUM;
3526   case ISD::FMINNUM:
3527     return ISD::FMAXNUM;
3528   case AMDGPUISD::FMAX_LEGACY:
3529     return AMDGPUISD::FMIN_LEGACY;
3530   case AMDGPUISD::FMIN_LEGACY:
3531     return  AMDGPUISD::FMAX_LEGACY;
3532   default:
3533     llvm_unreachable("invalid min/max opcode");
3534   }
3535 }
3536 
3537 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3538                                                  DAGCombinerInfo &DCI) const {
3539   SelectionDAG &DAG = DCI.DAG;
3540   SDValue N0 = N->getOperand(0);
3541   EVT VT = N->getValueType(0);
3542 
3543   unsigned Opc = N0.getOpcode();
3544 
3545   // If the input has multiple uses and we can either fold the negate down, or
3546   // the other uses cannot, give up. This both prevents unprofitable
3547   // transformations and infinite loops: we won't repeatedly try to fold around
3548   // a negate that has no 'good' form.
3549   if (N0.hasOneUse()) {
3550     // This may be able to fold into the source, but at a code size cost. Don't
3551     // fold if the fold into the user is free.
3552     if (allUsesHaveSourceMods(N, 0))
3553       return SDValue();
3554   } else {
3555     if (fnegFoldsIntoOp(Opc) &&
3556         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3557       return SDValue();
3558   }
3559 
3560   SDLoc SL(N);
3561   switch (Opc) {
3562   case ISD::FADD: {
3563     if (!mayIgnoreSignedZero(N0))
3564       return SDValue();
3565 
3566     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3567     SDValue LHS = N0.getOperand(0);
3568     SDValue RHS = N0.getOperand(1);
3569 
3570     if (LHS.getOpcode() != ISD::FNEG)
3571       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3572     else
3573       LHS = LHS.getOperand(0);
3574 
3575     if (RHS.getOpcode() != ISD::FNEG)
3576       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3577     else
3578       RHS = RHS.getOperand(0);
3579 
3580     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3581     if (!N0.hasOneUse())
3582       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3583     return Res;
3584   }
3585   case ISD::FMUL:
3586   case AMDGPUISD::FMUL_LEGACY: {
3587     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3588     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3589     SDValue LHS = N0.getOperand(0);
3590     SDValue RHS = N0.getOperand(1);
3591 
3592     if (LHS.getOpcode() == ISD::FNEG)
3593       LHS = LHS.getOperand(0);
3594     else if (RHS.getOpcode() == ISD::FNEG)
3595       RHS = RHS.getOperand(0);
3596     else
3597       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3598 
3599     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3600     if (!N0.hasOneUse())
3601       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3602     return Res;
3603   }
3604   case ISD::FMA:
3605   case ISD::FMAD: {
3606     if (!mayIgnoreSignedZero(N0))
3607       return SDValue();
3608 
3609     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3610     SDValue LHS = N0.getOperand(0);
3611     SDValue MHS = N0.getOperand(1);
3612     SDValue RHS = N0.getOperand(2);
3613 
3614     if (LHS.getOpcode() == ISD::FNEG)
3615       LHS = LHS.getOperand(0);
3616     else if (MHS.getOpcode() == ISD::FNEG)
3617       MHS = MHS.getOperand(0);
3618     else
3619       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3620 
3621     if (RHS.getOpcode() != ISD::FNEG)
3622       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3623     else
3624       RHS = RHS.getOperand(0);
3625 
3626     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3627     if (!N0.hasOneUse())
3628       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3629     return Res;
3630   }
3631   case ISD::FMAXNUM:
3632   case ISD::FMINNUM:
3633   case AMDGPUISD::FMAX_LEGACY:
3634   case AMDGPUISD::FMIN_LEGACY: {
3635     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3636     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3637     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3638     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3639 
3640     SDValue LHS = N0.getOperand(0);
3641     SDValue RHS = N0.getOperand(1);
3642 
3643     // 0 doesn't have a negated inline immediate.
3644     // TODO: Shouldn't fold 1/2pi either, and should be generalized to other
3645     // operations.
3646     if (isConstantFPZero(RHS))
3647       return SDValue();
3648 
3649     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3650     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3651     unsigned Opposite = inverseMinMax(Opc);
3652 
3653     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3654     if (!N0.hasOneUse())
3655       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3656     return Res;
3657   }
3658   case ISD::FP_EXTEND:
3659   case ISD::FTRUNC:
3660   case ISD::FRINT:
3661   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3662   case ISD::FSIN:
3663   case AMDGPUISD::RCP:
3664   case AMDGPUISD::RCP_LEGACY:
3665   case AMDGPUISD::SIN_HW: {
3666     SDValue CvtSrc = N0.getOperand(0);
3667     if (CvtSrc.getOpcode() == ISD::FNEG) {
3668       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3669       // (fneg (rcp (fneg x))) -> (rcp x)
3670       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3671     }
3672 
3673     if (!N0.hasOneUse())
3674       return SDValue();
3675 
3676     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3677     // (fneg (rcp x)) -> (rcp (fneg x))
3678     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3679     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3680   }
3681   case ISD::FP_ROUND: {
3682     SDValue CvtSrc = N0.getOperand(0);
3683 
3684     if (CvtSrc.getOpcode() == ISD::FNEG) {
3685       // (fneg (fp_round (fneg x))) -> (fp_round x)
3686       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3687                          CvtSrc.getOperand(0), N0.getOperand(1));
3688     }
3689 
3690     if (!N0.hasOneUse())
3691       return SDValue();
3692 
3693     // (fneg (fp_round x)) -> (fp_round (fneg x))
3694     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3695     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3696   }
3697   case ISD::FP16_TO_FP: {
3698     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3699     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3700     // Put the fneg back as a legal source operation that can be matched later.
3701     SDLoc SL(N);
3702 
3703     SDValue Src = N0.getOperand(0);
3704     EVT SrcVT = Src.getValueType();
3705 
3706     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3707     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3708                                   DAG.getConstant(0x8000, SL, SrcVT));
3709     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3710   }
3711   default:
3712     return SDValue();
3713   }
3714 }
3715 
3716 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3717                                                  DAGCombinerInfo &DCI) const {
3718   SelectionDAG &DAG = DCI.DAG;
3719   SDValue N0 = N->getOperand(0);
3720 
3721   if (!N0.hasOneUse())
3722     return SDValue();
3723 
3724   switch (N0.getOpcode()) {
3725   case ISD::FP16_TO_FP: {
3726     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3727     SDLoc SL(N);
3728     SDValue Src = N0.getOperand(0);
3729     EVT SrcVT = Src.getValueType();
3730 
3731     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3732     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3733                                   DAG.getConstant(0x7fff, SL, SrcVT));
3734     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3735   }
3736   default:
3737     return SDValue();
3738   }
3739 }
3740 
3741 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3742                                                 DAGCombinerInfo &DCI) const {
3743   SelectionDAG &DAG = DCI.DAG;
3744   SDLoc DL(N);
3745 
3746   switch(N->getOpcode()) {
3747   default:
3748     break;
3749   case ISD::BITCAST: {
3750     EVT DestVT = N->getValueType(0);
3751 
3752     // Push casts through vector builds. This helps avoid emitting a large
3753     // number of copies when materializing floating point vector constants.
3754     //
3755     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3756     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3757     if (DestVT.isVector()) {
3758       SDValue Src = N->getOperand(0);
3759       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3760         EVT SrcVT = Src.getValueType();
3761         unsigned NElts = DestVT.getVectorNumElements();
3762 
3763         if (SrcVT.getVectorNumElements() == NElts) {
3764           EVT DestEltVT = DestVT.getVectorElementType();
3765 
3766           SmallVector<SDValue, 8> CastedElts;
3767           SDLoc SL(N);
3768           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3769             SDValue Elt = Src.getOperand(I);
3770             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3771           }
3772 
3773           return DAG.getBuildVector(DestVT, SL, CastedElts);
3774         }
3775       }
3776     }
3777 
3778     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3779       break;
3780 
3781     // Fold bitcasts of constants.
3782     //
3783     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3784     // TODO: Generalize and move to DAGCombiner
3785     SDValue Src = N->getOperand(0);
3786     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3787       if (Src.getValueType() == MVT::i64) {
3788         SDLoc SL(N);
3789         uint64_t CVal = C->getZExtValue();
3790         return DAG.getNode(ISD::BUILD_VECTOR, SL, DestVT,
3791                            DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3792                            DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3793       }
3794     }
3795 
3796     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3797       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3798       SDLoc SL(N);
3799       uint64_t CVal = Val.getZExtValue();
3800       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3801                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3802                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3803 
3804       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3805     }
3806 
3807     break;
3808   }
3809   case ISD::SHL: {
3810     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3811       break;
3812 
3813     return performShlCombine(N, DCI);
3814   }
3815   case ISD::SRL: {
3816     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3817       break;
3818 
3819     return performSrlCombine(N, DCI);
3820   }
3821   case ISD::SRA: {
3822     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3823       break;
3824 
3825     return performSraCombine(N, DCI);
3826   }
3827   case ISD::TRUNCATE:
3828     return performTruncateCombine(N, DCI);
3829   case ISD::MUL:
3830     return performMulCombine(N, DCI);
3831   case ISD::MULHS:
3832     return performMulhsCombine(N, DCI);
3833   case ISD::MULHU:
3834     return performMulhuCombine(N, DCI);
3835   case AMDGPUISD::MUL_I24:
3836   case AMDGPUISD::MUL_U24:
3837   case AMDGPUISD::MULHI_I24:
3838   case AMDGPUISD::MULHI_U24: {
3839     // If the first call to simplify is successfull, then N may end up being
3840     // deleted, so we shouldn't call simplifyI24 again.
3841     simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI);
3842     return SDValue();
3843   }
3844   case AMDGPUISD::MUL_LOHI_I24:
3845   case AMDGPUISD::MUL_LOHI_U24:
3846     return performMulLoHi24Combine(N, DCI);
3847   case ISD::SELECT:
3848     return performSelectCombine(N, DCI);
3849   case ISD::FNEG:
3850     return performFNegCombine(N, DCI);
3851   case ISD::FABS:
3852     return performFAbsCombine(N, DCI);
3853   case AMDGPUISD::BFE_I32:
3854   case AMDGPUISD::BFE_U32: {
3855     assert(!N->getValueType(0).isVector() &&
3856            "Vector handling of BFE not implemented");
3857     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
3858     if (!Width)
3859       break;
3860 
3861     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
3862     if (WidthVal == 0)
3863       return DAG.getConstant(0, DL, MVT::i32);
3864 
3865     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
3866     if (!Offset)
3867       break;
3868 
3869     SDValue BitsFrom = N->getOperand(0);
3870     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
3871 
3872     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
3873 
3874     if (OffsetVal == 0) {
3875       // This is already sign / zero extended, so try to fold away extra BFEs.
3876       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
3877 
3878       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
3879       if (OpSignBits >= SignBits)
3880         return BitsFrom;
3881 
3882       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
3883       if (Signed) {
3884         // This is a sign_extend_inreg. Replace it to take advantage of existing
3885         // DAG Combines. If not eliminated, we will match back to BFE during
3886         // selection.
3887 
3888         // TODO: The sext_inreg of extended types ends, although we can could
3889         // handle them in a single BFE.
3890         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
3891                            DAG.getValueType(SmallVT));
3892       }
3893 
3894       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
3895     }
3896 
3897     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
3898       if (Signed) {
3899         return constantFoldBFE<int32_t>(DAG,
3900                                         CVal->getSExtValue(),
3901                                         OffsetVal,
3902                                         WidthVal,
3903                                         DL);
3904       }
3905 
3906       return constantFoldBFE<uint32_t>(DAG,
3907                                        CVal->getZExtValue(),
3908                                        OffsetVal,
3909                                        WidthVal,
3910                                        DL);
3911     }
3912 
3913     if ((OffsetVal + WidthVal) >= 32 &&
3914         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
3915       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
3916       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
3917                          BitsFrom, ShiftVal);
3918     }
3919 
3920     if (BitsFrom.hasOneUse()) {
3921       APInt Demanded = APInt::getBitsSet(32,
3922                                          OffsetVal,
3923                                          OffsetVal + WidthVal);
3924 
3925       KnownBits Known;
3926       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
3927                                             !DCI.isBeforeLegalizeOps());
3928       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
3929       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
3930           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
3931         DCI.CommitTargetLoweringOpt(TLO);
3932       }
3933     }
3934 
3935     break;
3936   }
3937   case ISD::LOAD:
3938     return performLoadCombine(N, DCI);
3939   case ISD::STORE:
3940     return performStoreCombine(N, DCI);
3941   case AMDGPUISD::RCP: {
3942     if (const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0))) {
3943       // XXX - Should this flush denormals?
3944       const APFloat &Val = CFP->getValueAPF();
3945       APFloat One(Val.getSemantics(), "1.0");
3946       return DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3947     }
3948 
3949     break;
3950   }
3951   case ISD::AssertZext:
3952   case ISD::AssertSext:
3953     return performAssertSZExtCombine(N, DCI);
3954   }
3955   return SDValue();
3956 }
3957 
3958 //===----------------------------------------------------------------------===//
3959 // Helper functions
3960 //===----------------------------------------------------------------------===//
3961 
3962 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
3963                                                    const TargetRegisterClass *RC,
3964                                                    unsigned Reg, EVT VT,
3965                                                    const SDLoc &SL,
3966                                                    bool RawReg) const {
3967   MachineFunction &MF = DAG.getMachineFunction();
3968   MachineRegisterInfo &MRI = MF.getRegInfo();
3969   unsigned VReg;
3970 
3971   if (!MRI.isLiveIn(Reg)) {
3972     VReg = MRI.createVirtualRegister(RC);
3973     MRI.addLiveIn(Reg, VReg);
3974   } else {
3975     VReg = MRI.getLiveInVirtReg(Reg);
3976   }
3977 
3978   if (RawReg)
3979     return DAG.getRegister(VReg, VT);
3980 
3981   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
3982 }
3983 
3984 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
3985                                                   EVT VT,
3986                                                   const SDLoc &SL,
3987                                                   int64_t Offset) const {
3988   MachineFunction &MF = DAG.getMachineFunction();
3989   MachineFrameInfo &MFI = MF.getFrameInfo();
3990 
3991   int FI = MFI.CreateFixedObject(VT.getStoreSize(), Offset, true);
3992   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
3993   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
3994 
3995   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
3996                      MachineMemOperand::MODereferenceable |
3997                      MachineMemOperand::MOInvariant);
3998 }
3999 
4000 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4001                                                    const SDLoc &SL,
4002                                                    SDValue Chain,
4003                                                    SDValue StackPtr,
4004                                                    SDValue ArgVal,
4005                                                    int64_t Offset) const {
4006   MachineFunction &MF = DAG.getMachineFunction();
4007   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4008 
4009   SDValue Ptr = DAG.getObjectPtrOffset(SL, StackPtr, Offset);
4010   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4011                                MachineMemOperand::MODereferenceable);
4012   return Store;
4013 }
4014 
4015 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4016                                              const TargetRegisterClass *RC,
4017                                              EVT VT, const SDLoc &SL,
4018                                              const ArgDescriptor &Arg) const {
4019   assert(Arg && "Attempting to load missing argument");
4020 
4021   if (Arg.isRegister())
4022     return CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL);
4023   return loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4024 }
4025 
4026 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4027     const AMDGPUMachineFunction *MFI, const ImplicitParameter Param) const {
4028   unsigned Alignment = Subtarget->getAlignmentForImplicitArgPtr();
4029   uint64_t ArgOffset = alignTo(MFI->getABIArgOffset(), Alignment);
4030   switch (Param) {
4031   case GRID_DIM:
4032     return ArgOffset;
4033   case GRID_OFFSET:
4034     return ArgOffset + 4;
4035   }
4036   llvm_unreachable("unexpected implicit parameter type");
4037 }
4038 
4039 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4040 
4041 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4042   switch ((AMDGPUISD::NodeType)Opcode) {
4043   case AMDGPUISD::FIRST_NUMBER: break;
4044   // AMDIL DAG nodes
4045   NODE_NAME_CASE(UMUL);
4046   NODE_NAME_CASE(BRANCH_COND);
4047 
4048   // AMDGPU DAG nodes
4049   NODE_NAME_CASE(IF)
4050   NODE_NAME_CASE(ELSE)
4051   NODE_NAME_CASE(LOOP)
4052   NODE_NAME_CASE(CALL)
4053   NODE_NAME_CASE(TC_RETURN)
4054   NODE_NAME_CASE(TRAP)
4055   NODE_NAME_CASE(RET_FLAG)
4056   NODE_NAME_CASE(RETURN_TO_EPILOG)
4057   NODE_NAME_CASE(ENDPGM)
4058   NODE_NAME_CASE(DWORDADDR)
4059   NODE_NAME_CASE(FRACT)
4060   NODE_NAME_CASE(SETCC)
4061   NODE_NAME_CASE(SETREG)
4062   NODE_NAME_CASE(FMA_W_CHAIN)
4063   NODE_NAME_CASE(FMUL_W_CHAIN)
4064   NODE_NAME_CASE(CLAMP)
4065   NODE_NAME_CASE(COS_HW)
4066   NODE_NAME_CASE(SIN_HW)
4067   NODE_NAME_CASE(FMAX_LEGACY)
4068   NODE_NAME_CASE(FMIN_LEGACY)
4069   NODE_NAME_CASE(FMAX3)
4070   NODE_NAME_CASE(SMAX3)
4071   NODE_NAME_CASE(UMAX3)
4072   NODE_NAME_CASE(FMIN3)
4073   NODE_NAME_CASE(SMIN3)
4074   NODE_NAME_CASE(UMIN3)
4075   NODE_NAME_CASE(FMED3)
4076   NODE_NAME_CASE(SMED3)
4077   NODE_NAME_CASE(UMED3)
4078   NODE_NAME_CASE(URECIP)
4079   NODE_NAME_CASE(DIV_SCALE)
4080   NODE_NAME_CASE(DIV_FMAS)
4081   NODE_NAME_CASE(DIV_FIXUP)
4082   NODE_NAME_CASE(FMAD_FTZ)
4083   NODE_NAME_CASE(TRIG_PREOP)
4084   NODE_NAME_CASE(RCP)
4085   NODE_NAME_CASE(RSQ)
4086   NODE_NAME_CASE(RCP_LEGACY)
4087   NODE_NAME_CASE(RSQ_LEGACY)
4088   NODE_NAME_CASE(FMUL_LEGACY)
4089   NODE_NAME_CASE(RSQ_CLAMP)
4090   NODE_NAME_CASE(LDEXP)
4091   NODE_NAME_CASE(FP_CLASS)
4092   NODE_NAME_CASE(DOT4)
4093   NODE_NAME_CASE(CARRY)
4094   NODE_NAME_CASE(BORROW)
4095   NODE_NAME_CASE(BFE_U32)
4096   NODE_NAME_CASE(BFE_I32)
4097   NODE_NAME_CASE(BFI)
4098   NODE_NAME_CASE(BFM)
4099   NODE_NAME_CASE(FFBH_U32)
4100   NODE_NAME_CASE(FFBH_I32)
4101   NODE_NAME_CASE(FFBL_B32)
4102   NODE_NAME_CASE(MUL_U24)
4103   NODE_NAME_CASE(MUL_I24)
4104   NODE_NAME_CASE(MULHI_U24)
4105   NODE_NAME_CASE(MULHI_I24)
4106   NODE_NAME_CASE(MUL_LOHI_U24)
4107   NODE_NAME_CASE(MUL_LOHI_I24)
4108   NODE_NAME_CASE(MAD_U24)
4109   NODE_NAME_CASE(MAD_I24)
4110   NODE_NAME_CASE(MAD_I64_I32)
4111   NODE_NAME_CASE(MAD_U64_U32)
4112   NODE_NAME_CASE(TEXTURE_FETCH)
4113   NODE_NAME_CASE(EXPORT)
4114   NODE_NAME_CASE(EXPORT_DONE)
4115   NODE_NAME_CASE(R600_EXPORT)
4116   NODE_NAME_CASE(CONST_ADDRESS)
4117   NODE_NAME_CASE(REGISTER_LOAD)
4118   NODE_NAME_CASE(REGISTER_STORE)
4119   NODE_NAME_CASE(SAMPLE)
4120   NODE_NAME_CASE(SAMPLEB)
4121   NODE_NAME_CASE(SAMPLED)
4122   NODE_NAME_CASE(SAMPLEL)
4123   NODE_NAME_CASE(CVT_F32_UBYTE0)
4124   NODE_NAME_CASE(CVT_F32_UBYTE1)
4125   NODE_NAME_CASE(CVT_F32_UBYTE2)
4126   NODE_NAME_CASE(CVT_F32_UBYTE3)
4127   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4128   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4129   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4130   NODE_NAME_CASE(CVT_PK_I16_I32)
4131   NODE_NAME_CASE(CVT_PK_U16_U32)
4132   NODE_NAME_CASE(FP_TO_FP16)
4133   NODE_NAME_CASE(FP16_ZEXT)
4134   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4135   NODE_NAME_CASE(CONST_DATA_PTR)
4136   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4137   NODE_NAME_CASE(KILL)
4138   NODE_NAME_CASE(DUMMY_CHAIN)
4139   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4140   NODE_NAME_CASE(INIT_EXEC)
4141   NODE_NAME_CASE(INIT_EXEC_FROM_INPUT)
4142   NODE_NAME_CASE(SENDMSG)
4143   NODE_NAME_CASE(SENDMSGHALT)
4144   NODE_NAME_CASE(INTERP_MOV)
4145   NODE_NAME_CASE(INTERP_P1)
4146   NODE_NAME_CASE(INTERP_P2)
4147   NODE_NAME_CASE(STORE_MSKOR)
4148   NODE_NAME_CASE(LOAD_CONSTANT)
4149   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4150   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_X3)
4151   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4152   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4153   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4154   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4155   NODE_NAME_CASE(ATOMIC_INC)
4156   NODE_NAME_CASE(ATOMIC_DEC)
4157   NODE_NAME_CASE(ATOMIC_LOAD_FADD)
4158   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4159   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4160   NODE_NAME_CASE(BUFFER_LOAD)
4161   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4162   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4163   NODE_NAME_CASE(BUFFER_STORE)
4164   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4165   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4166   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4167   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4168   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4169   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4170   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4171   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4172   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4173   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4174   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4175   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4176   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4177   NODE_NAME_CASE(IMAGE_LOAD)
4178   NODE_NAME_CASE(IMAGE_LOAD_MIP)
4179   NODE_NAME_CASE(IMAGE_STORE)
4180   NODE_NAME_CASE(IMAGE_STORE_MIP)
4181   // Basic sample.
4182   NODE_NAME_CASE(IMAGE_SAMPLE)
4183   NODE_NAME_CASE(IMAGE_SAMPLE_CL)
4184   NODE_NAME_CASE(IMAGE_SAMPLE_D)
4185   NODE_NAME_CASE(IMAGE_SAMPLE_D_CL)
4186   NODE_NAME_CASE(IMAGE_SAMPLE_L)
4187   NODE_NAME_CASE(IMAGE_SAMPLE_B)
4188   NODE_NAME_CASE(IMAGE_SAMPLE_B_CL)
4189   NODE_NAME_CASE(IMAGE_SAMPLE_LZ)
4190   NODE_NAME_CASE(IMAGE_SAMPLE_CD)
4191   NODE_NAME_CASE(IMAGE_SAMPLE_CD_CL)
4192   // Sample with comparison.
4193   NODE_NAME_CASE(IMAGE_SAMPLE_C)
4194   NODE_NAME_CASE(IMAGE_SAMPLE_C_CL)
4195   NODE_NAME_CASE(IMAGE_SAMPLE_C_D)
4196   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_CL)
4197   NODE_NAME_CASE(IMAGE_SAMPLE_C_L)
4198   NODE_NAME_CASE(IMAGE_SAMPLE_C_B)
4199   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_CL)
4200   NODE_NAME_CASE(IMAGE_SAMPLE_C_LZ)
4201   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD)
4202   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_CL)
4203   // Sample with offsets.
4204   NODE_NAME_CASE(IMAGE_SAMPLE_O)
4205   NODE_NAME_CASE(IMAGE_SAMPLE_CL_O)
4206   NODE_NAME_CASE(IMAGE_SAMPLE_D_O)
4207   NODE_NAME_CASE(IMAGE_SAMPLE_D_CL_O)
4208   NODE_NAME_CASE(IMAGE_SAMPLE_L_O)
4209   NODE_NAME_CASE(IMAGE_SAMPLE_B_O)
4210   NODE_NAME_CASE(IMAGE_SAMPLE_B_CL_O)
4211   NODE_NAME_CASE(IMAGE_SAMPLE_LZ_O)
4212   NODE_NAME_CASE(IMAGE_SAMPLE_CD_O)
4213   NODE_NAME_CASE(IMAGE_SAMPLE_CD_CL_O)
4214   // Sample with comparison and offsets.
4215   NODE_NAME_CASE(IMAGE_SAMPLE_C_O)
4216   NODE_NAME_CASE(IMAGE_SAMPLE_C_CL_O)
4217   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_O)
4218   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_CL_O)
4219   NODE_NAME_CASE(IMAGE_SAMPLE_C_L_O)
4220   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_O)
4221   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_CL_O)
4222   NODE_NAME_CASE(IMAGE_SAMPLE_C_LZ_O)
4223   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_O)
4224   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_CL_O)
4225   // Basic gather4.
4226   NODE_NAME_CASE(IMAGE_GATHER4)
4227   NODE_NAME_CASE(IMAGE_GATHER4_CL)
4228   NODE_NAME_CASE(IMAGE_GATHER4_L)
4229   NODE_NAME_CASE(IMAGE_GATHER4_B)
4230   NODE_NAME_CASE(IMAGE_GATHER4_B_CL)
4231   NODE_NAME_CASE(IMAGE_GATHER4_LZ)
4232   // Gather4 with comparison.
4233   NODE_NAME_CASE(IMAGE_GATHER4_C)
4234   NODE_NAME_CASE(IMAGE_GATHER4_C_CL)
4235   NODE_NAME_CASE(IMAGE_GATHER4_C_L)
4236   NODE_NAME_CASE(IMAGE_GATHER4_C_B)
4237   NODE_NAME_CASE(IMAGE_GATHER4_C_B_CL)
4238   NODE_NAME_CASE(IMAGE_GATHER4_C_LZ)
4239   // Gather4 with offsets.
4240   NODE_NAME_CASE(IMAGE_GATHER4_O)
4241   NODE_NAME_CASE(IMAGE_GATHER4_CL_O)
4242   NODE_NAME_CASE(IMAGE_GATHER4_L_O)
4243   NODE_NAME_CASE(IMAGE_GATHER4_B_O)
4244   NODE_NAME_CASE(IMAGE_GATHER4_B_CL_O)
4245   NODE_NAME_CASE(IMAGE_GATHER4_LZ_O)
4246   // Gather4 with comparison and offsets.
4247   NODE_NAME_CASE(IMAGE_GATHER4_C_O)
4248   NODE_NAME_CASE(IMAGE_GATHER4_C_CL_O)
4249   NODE_NAME_CASE(IMAGE_GATHER4_C_L_O)
4250   NODE_NAME_CASE(IMAGE_GATHER4_C_B_O)
4251   NODE_NAME_CASE(IMAGE_GATHER4_C_B_CL_O)
4252   NODE_NAME_CASE(IMAGE_GATHER4_C_LZ_O)
4253 
4254   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4255   }
4256   return nullptr;
4257 }
4258 
4259 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4260                                               SelectionDAG &DAG, int Enabled,
4261                                               int &RefinementSteps,
4262                                               bool &UseOneConstNR,
4263                                               bool Reciprocal) const {
4264   EVT VT = Operand.getValueType();
4265 
4266   if (VT == MVT::f32) {
4267     RefinementSteps = 0;
4268     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4269   }
4270 
4271   // TODO: There is also f64 rsq instruction, but the documentation is less
4272   // clear on its precision.
4273 
4274   return SDValue();
4275 }
4276 
4277 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4278                                                SelectionDAG &DAG, int Enabled,
4279                                                int &RefinementSteps) const {
4280   EVT VT = Operand.getValueType();
4281 
4282   if (VT == MVT::f32) {
4283     // Reciprocal, < 1 ulp error.
4284     //
4285     // This reciprocal approximation converges to < 0.5 ulp error with one
4286     // newton rhapson performed with two fused multiple adds (FMAs).
4287 
4288     RefinementSteps = 0;
4289     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4290   }
4291 
4292   // TODO: There is also f64 rcp instruction, but the documentation is less
4293   // clear on its precision.
4294 
4295   return SDValue();
4296 }
4297 
4298 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4299     const SDValue Op, KnownBits &Known,
4300     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4301 
4302   Known.resetAll(); // Don't know anything.
4303 
4304   unsigned Opc = Op.getOpcode();
4305 
4306   switch (Opc) {
4307   default:
4308     break;
4309   case AMDGPUISD::CARRY:
4310   case AMDGPUISD::BORROW: {
4311     Known.Zero = APInt::getHighBitsSet(32, 31);
4312     break;
4313   }
4314 
4315   case AMDGPUISD::BFE_I32:
4316   case AMDGPUISD::BFE_U32: {
4317     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4318     if (!CWidth)
4319       return;
4320 
4321     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4322 
4323     if (Opc == AMDGPUISD::BFE_U32)
4324       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4325 
4326     break;
4327   }
4328   case AMDGPUISD::FP_TO_FP16:
4329   case AMDGPUISD::FP16_ZEXT: {
4330     unsigned BitWidth = Known.getBitWidth();
4331 
4332     // High bits are zero.
4333     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4334     break;
4335   }
4336   case AMDGPUISD::MUL_U24:
4337   case AMDGPUISD::MUL_I24: {
4338     KnownBits LHSKnown, RHSKnown;
4339     DAG.computeKnownBits(Op.getOperand(0), LHSKnown, Depth + 1);
4340     DAG.computeKnownBits(Op.getOperand(1), RHSKnown, Depth + 1);
4341 
4342     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4343                       RHSKnown.countMinTrailingZeros();
4344     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4345 
4346     unsigned LHSValBits = 32 - std::max(LHSKnown.countMinSignBits(), 8u);
4347     unsigned RHSValBits = 32 - std::max(RHSKnown.countMinSignBits(), 8u);
4348     unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4349     if (MaxValBits >= 32)
4350       break;
4351     bool Negative = false;
4352     if (Opc == AMDGPUISD::MUL_I24) {
4353       bool LHSNegative = !!(LHSKnown.One  & (1 << 23));
4354       bool LHSPositive = !!(LHSKnown.Zero & (1 << 23));
4355       bool RHSNegative = !!(RHSKnown.One  & (1 << 23));
4356       bool RHSPositive = !!(RHSKnown.Zero & (1 << 23));
4357       if ((!LHSNegative && !LHSPositive) || (!RHSNegative && !RHSPositive))
4358         break;
4359       Negative = (LHSNegative && RHSPositive) || (LHSPositive && RHSNegative);
4360     }
4361     if (Negative)
4362       Known.One.setHighBits(32 - MaxValBits);
4363     else
4364       Known.Zero.setHighBits(32 - MaxValBits);
4365     break;
4366   }
4367   case ISD::INTRINSIC_WO_CHAIN: {
4368     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4369     switch (IID) {
4370     case Intrinsic::amdgcn_mbcnt_lo:
4371     case Intrinsic::amdgcn_mbcnt_hi: {
4372       // These return at most the wavefront size - 1.
4373       unsigned Size = Op.getValueType().getSizeInBits();
4374       Known.Zero.setHighBits(Size - Subtarget->getWavefrontSizeLog2());
4375       break;
4376     }
4377     default:
4378       break;
4379     }
4380   }
4381   }
4382 }
4383 
4384 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4385     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4386     unsigned Depth) const {
4387   switch (Op.getOpcode()) {
4388   case AMDGPUISD::BFE_I32: {
4389     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4390     if (!Width)
4391       return 1;
4392 
4393     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4394     if (!isNullConstant(Op.getOperand(1)))
4395       return SignBits;
4396 
4397     // TODO: Could probably figure something out with non-0 offsets.
4398     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4399     return std::max(SignBits, Op0SignBits);
4400   }
4401 
4402   case AMDGPUISD::BFE_U32: {
4403     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4404     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4405   }
4406 
4407   case AMDGPUISD::CARRY:
4408   case AMDGPUISD::BORROW:
4409     return 31;
4410   case AMDGPUISD::FP_TO_FP16:
4411   case AMDGPUISD::FP16_ZEXT:
4412     return 16;
4413   default:
4414     return 1;
4415   }
4416 }
4417