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   case MVT::v4i16:
78   case MVT::v4f16: {
79     // Up to SGPR0-SGPR39
80     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
81                           &AMDGPU::SGPR_64RegClass, 20);
82   }
83   default:
84     return false;
85   }
86 }
87 
88 // Allocate up to VGPR31.
89 //
90 // TODO: Since there are no VGPR alignent requirements would it be better to
91 // split into individual scalar registers?
92 static bool allocateVGPRTuple(unsigned ValNo, MVT ValVT, MVT LocVT,
93                               CCValAssign::LocInfo LocInfo,
94                               ISD::ArgFlagsTy ArgFlags, CCState &State) {
95   switch (LocVT.SimpleTy) {
96   case MVT::i64:
97   case MVT::f64:
98   case MVT::v2i32:
99   case MVT::v2f32:
100   case MVT::v4i16:
101   case MVT::v4f16: {
102     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
103                           &AMDGPU::VReg_64RegClass, 31);
104   }
105   case MVT::v4i32:
106   case MVT::v4f32:
107   case MVT::v2i64:
108   case MVT::v2f64: {
109     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
110                           &AMDGPU::VReg_128RegClass, 29);
111   }
112   case MVT::v8i32:
113   case MVT::v8f32: {
114     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
115                           &AMDGPU::VReg_256RegClass, 25);
116 
117   }
118   case MVT::v16i32:
119   case MVT::v16f32: {
120     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
121                           &AMDGPU::VReg_512RegClass, 17);
122 
123   }
124   default:
125     return false;
126   }
127 }
128 
129 #include "AMDGPUGenCallingConv.inc"
130 
131 // Find a larger type to do a load / store of a vector with.
132 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
133   unsigned StoreSize = VT.getStoreSizeInBits();
134   if (StoreSize <= 32)
135     return EVT::getIntegerVT(Ctx, StoreSize);
136 
137   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
138   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
139 }
140 
141 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
142   KnownBits Known;
143   EVT VT = Op.getValueType();
144   DAG.computeKnownBits(Op, Known);
145 
146   return VT.getSizeInBits() - Known.countMinLeadingZeros();
147 }
148 
149 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
150   EVT VT = Op.getValueType();
151 
152   // In order for this to be a signed 24-bit value, bit 23, must
153   // be a sign bit.
154   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
155 }
156 
157 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
158                                            const AMDGPUSubtarget &STI)
159     : TargetLowering(TM), Subtarget(&STI) {
160   AMDGPUASI = AMDGPU::getAMDGPUAS(TM);
161   // Lower floating point store/load to integer store/load to reduce the number
162   // of patterns in tablegen.
163   setOperationAction(ISD::LOAD, MVT::f32, Promote);
164   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
165 
166   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
167   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
168 
169   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
170   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
171 
172   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
173   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
174 
175   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
176   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
177 
178   setOperationAction(ISD::LOAD, MVT::i64, Promote);
179   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
180 
181   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
182   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
183 
184   setOperationAction(ISD::LOAD, MVT::f64, Promote);
185   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
186 
187   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
188   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
189 
190   // There are no 64-bit extloads. These should be done as a 32-bit extload and
191   // an extension to 64-bit.
192   for (MVT VT : MVT::integer_valuetypes()) {
193     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
194     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
195     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
196   }
197 
198   for (MVT VT : MVT::integer_valuetypes()) {
199     if (VT == MVT::i64)
200       continue;
201 
202     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
203     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
204     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
205     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
206 
207     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
208     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
209     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
210     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
211 
212     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
213     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
214     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
215     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
216   }
217 
218   for (MVT VT : MVT::integer_vector_valuetypes()) {
219     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
220     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
221     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
222     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
223     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
224     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
225     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
226     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
227     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
228     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
229     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
230     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
231   }
232 
233   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
234   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
235   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
236   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
237 
238   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
239   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
240   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
241   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
242 
243   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
244   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
245   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
246   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
247 
248   setOperationAction(ISD::STORE, MVT::f32, Promote);
249   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
250 
251   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
252   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
253 
254   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
255   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
256 
257   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
258   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
259 
260   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
261   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
262 
263   setOperationAction(ISD::STORE, MVT::i64, Promote);
264   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
265 
266   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
267   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
268 
269   setOperationAction(ISD::STORE, MVT::f64, Promote);
270   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
271 
272   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
273   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
274 
275   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
276   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
277   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
278   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
279 
280   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
281   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
282   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
283   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
284 
285   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
286   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
287   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
288   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
289 
290   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
291   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
292 
293   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
294   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
295 
296   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
297   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
298 
299   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
300   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
301 
302 
303   setOperationAction(ISD::Constant, MVT::i32, Legal);
304   setOperationAction(ISD::Constant, MVT::i64, Legal);
305   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
306   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
307 
308   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
309   setOperationAction(ISD::BRIND, MVT::Other, Expand);
310 
311   // This is totally unsupported, just custom lower to produce an error.
312   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
313 
314   // Library functions.  These default to Expand, but we have instructions
315   // for them.
316   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
317   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
318   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
319   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
320   setOperationAction(ISD::FABS,   MVT::f32, Legal);
321   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
322   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
323   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
324   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
325   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
326 
327   setOperationAction(ISD::FROUND, MVT::f32, Custom);
328   setOperationAction(ISD::FROUND, MVT::f64, Custom);
329 
330   setOperationAction(ISD::FLOG, MVT::f32, Custom);
331   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
332 
333   if (Subtarget->has16BitInsts()) {
334     setOperationAction(ISD::FLOG, MVT::f16, Custom);
335     setOperationAction(ISD::FLOG10, MVT::f16, Custom);
336   }
337 
338   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
339   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
340 
341   setOperationAction(ISD::FREM, MVT::f32, Custom);
342   setOperationAction(ISD::FREM, MVT::f64, Custom);
343 
344   // v_mad_f32 does not support denormals according to some sources.
345   if (!Subtarget->hasFP32Denormals())
346     setOperationAction(ISD::FMAD, MVT::f32, Legal);
347 
348   // Expand to fneg + fadd.
349   setOperationAction(ISD::FSUB, MVT::f64, Expand);
350 
351   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
352   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
353   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
354   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
355   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
356   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
357   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
358   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
359   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
360   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
361 
362   if (Subtarget->getGeneration() < AMDGPUSubtarget::SEA_ISLANDS) {
363     setOperationAction(ISD::FCEIL, MVT::f64, Custom);
364     setOperationAction(ISD::FTRUNC, MVT::f64, Custom);
365     setOperationAction(ISD::FRINT, MVT::f64, Custom);
366     setOperationAction(ISD::FFLOOR, MVT::f64, Custom);
367   }
368 
369   if (!Subtarget->hasBFI()) {
370     // fcopysign can be done in a single instruction with BFI.
371     setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
372     setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
373   }
374 
375   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
376   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
377   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
378 
379   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
380   for (MVT VT : ScalarIntVTs) {
381     // These should use [SU]DIVREM, so set them to expand
382     setOperationAction(ISD::SDIV, VT, Expand);
383     setOperationAction(ISD::UDIV, VT, Expand);
384     setOperationAction(ISD::SREM, VT, Expand);
385     setOperationAction(ISD::UREM, VT, Expand);
386 
387     // GPU does not have divrem function for signed or unsigned.
388     setOperationAction(ISD::SDIVREM, VT, Custom);
389     setOperationAction(ISD::UDIVREM, VT, Custom);
390 
391     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
392     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
393     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
394 
395     setOperationAction(ISD::BSWAP, VT, Expand);
396     setOperationAction(ISD::CTTZ, VT, Expand);
397     setOperationAction(ISD::CTLZ, VT, Expand);
398 
399     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
400     setOperationAction(ISD::ADDC, VT, Legal);
401     setOperationAction(ISD::SUBC, VT, Legal);
402     setOperationAction(ISD::ADDE, VT, Legal);
403     setOperationAction(ISD::SUBE, VT, Legal);
404   }
405 
406   if (!Subtarget->hasBCNT(32))
407     setOperationAction(ISD::CTPOP, MVT::i32, Expand);
408 
409   if (!Subtarget->hasBCNT(64))
410     setOperationAction(ISD::CTPOP, MVT::i64, Expand);
411 
412   // The hardware supports 32-bit ROTR, but not ROTL.
413   setOperationAction(ISD::ROTL, MVT::i32, Expand);
414   setOperationAction(ISD::ROTL, MVT::i64, Expand);
415   setOperationAction(ISD::ROTR, MVT::i64, Expand);
416 
417   setOperationAction(ISD::MUL, MVT::i64, Expand);
418   setOperationAction(ISD::MULHU, MVT::i64, Expand);
419   setOperationAction(ISD::MULHS, MVT::i64, Expand);
420   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
421   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
422   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
423   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
424   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
425 
426   setOperationAction(ISD::SMIN, MVT::i32, Legal);
427   setOperationAction(ISD::UMIN, MVT::i32, Legal);
428   setOperationAction(ISD::SMAX, MVT::i32, Legal);
429   setOperationAction(ISD::UMAX, MVT::i32, Legal);
430 
431   if (Subtarget->hasFFBH())
432     setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i32, Custom);
433 
434   if (Subtarget->hasFFBL())
435     setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i32, Custom);
436 
437   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
438   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
439   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
440   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
441 
442   // We only really have 32-bit BFE instructions (and 16-bit on VI).
443   //
444   // On SI+ there are 64-bit BFEs, but they are scalar only and there isn't any
445   // effort to match them now. We want this to be false for i64 cases when the
446   // extraction isn't restricted to the upper or lower half. Ideally we would
447   // have some pass reduce 64-bit extracts to 32-bit if possible. Extracts that
448   // span the midpoint are probably relatively rare, so don't worry about them
449   // for now.
450   if (Subtarget->hasBFE())
451     setHasExtractBitsInsn(true);
452 
453   static const MVT::SimpleValueType VectorIntTypes[] = {
454     MVT::v2i32, MVT::v4i32
455   };
456 
457   for (MVT VT : VectorIntTypes) {
458     // Expand the following operations for the current type by default.
459     setOperationAction(ISD::ADD,  VT, Expand);
460     setOperationAction(ISD::AND,  VT, Expand);
461     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
462     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
463     setOperationAction(ISD::MUL,  VT, Expand);
464     setOperationAction(ISD::MULHU, VT, Expand);
465     setOperationAction(ISD::MULHS, VT, Expand);
466     setOperationAction(ISD::OR,   VT, Expand);
467     setOperationAction(ISD::SHL,  VT, Expand);
468     setOperationAction(ISD::SRA,  VT, Expand);
469     setOperationAction(ISD::SRL,  VT, Expand);
470     setOperationAction(ISD::ROTL, VT, Expand);
471     setOperationAction(ISD::ROTR, VT, Expand);
472     setOperationAction(ISD::SUB,  VT, Expand);
473     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
474     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
475     setOperationAction(ISD::SDIV, VT, Expand);
476     setOperationAction(ISD::UDIV, VT, Expand);
477     setOperationAction(ISD::SREM, VT, Expand);
478     setOperationAction(ISD::UREM, VT, Expand);
479     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
480     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
481     setOperationAction(ISD::SDIVREM, VT, Custom);
482     setOperationAction(ISD::UDIVREM, VT, Expand);
483     setOperationAction(ISD::SELECT, VT, Expand);
484     setOperationAction(ISD::VSELECT, VT, Expand);
485     setOperationAction(ISD::SELECT_CC, VT, Expand);
486     setOperationAction(ISD::XOR,  VT, Expand);
487     setOperationAction(ISD::BSWAP, VT, Expand);
488     setOperationAction(ISD::CTPOP, VT, Expand);
489     setOperationAction(ISD::CTTZ, VT, Expand);
490     setOperationAction(ISD::CTLZ, VT, Expand);
491     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
492     setOperationAction(ISD::SETCC, VT, Expand);
493   }
494 
495   static const MVT::SimpleValueType FloatVectorTypes[] = {
496     MVT::v2f32, MVT::v4f32
497   };
498 
499   for (MVT VT : FloatVectorTypes) {
500     setOperationAction(ISD::FABS, VT, Expand);
501     setOperationAction(ISD::FMINNUM, VT, Expand);
502     setOperationAction(ISD::FMAXNUM, VT, Expand);
503     setOperationAction(ISD::FADD, VT, Expand);
504     setOperationAction(ISD::FCEIL, VT, Expand);
505     setOperationAction(ISD::FCOS, VT, Expand);
506     setOperationAction(ISD::FDIV, VT, Expand);
507     setOperationAction(ISD::FEXP2, VT, Expand);
508     setOperationAction(ISD::FLOG2, VT, Expand);
509     setOperationAction(ISD::FREM, VT, Expand);
510     setOperationAction(ISD::FLOG, VT, Expand);
511     setOperationAction(ISD::FLOG10, VT, Expand);
512     setOperationAction(ISD::FPOW, VT, Expand);
513     setOperationAction(ISD::FFLOOR, VT, Expand);
514     setOperationAction(ISD::FTRUNC, VT, Expand);
515     setOperationAction(ISD::FMUL, VT, Expand);
516     setOperationAction(ISD::FMA, VT, Expand);
517     setOperationAction(ISD::FRINT, VT, Expand);
518     setOperationAction(ISD::FNEARBYINT, VT, Expand);
519     setOperationAction(ISD::FSQRT, VT, Expand);
520     setOperationAction(ISD::FSIN, VT, Expand);
521     setOperationAction(ISD::FSUB, VT, Expand);
522     setOperationAction(ISD::FNEG, VT, Expand);
523     setOperationAction(ISD::VSELECT, VT, Expand);
524     setOperationAction(ISD::SELECT_CC, VT, Expand);
525     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
526     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
527     setOperationAction(ISD::SETCC, VT, Expand);
528   }
529 
530   // This causes using an unrolled select operation rather than expansion with
531   // bit operations. This is in general better, but the alternative using BFI
532   // instructions may be better if the select sources are SGPRs.
533   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
534   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
535 
536   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
537   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
538 
539   // There are no libcalls of any kind.
540   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
541     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
542 
543   setBooleanContents(ZeroOrNegativeOneBooleanContent);
544   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
545 
546   setSchedulingPreference(Sched::RegPressure);
547   setJumpIsExpensive(true);
548 
549   // FIXME: This is only partially true. If we have to do vector compares, any
550   // SGPR pair can be a condition register. If we have a uniform condition, we
551   // are better off doing SALU operations, where there is only one SCC. For now,
552   // we don't have a way of knowing during instruction selection if a condition
553   // will be uniform and we always use vector compares. Assume we are using
554   // vector compares until that is fixed.
555   setHasMultipleConditionRegisters(true);
556 
557   // SI at least has hardware support for floating point exceptions, but no way
558   // of using or handling them is implemented. They are also optional in OpenCL
559   // (Section 7.3)
560   setHasFloatingPointExceptions(Subtarget->hasFPExceptions());
561 
562   PredictableSelectIsExpensive = false;
563 
564   // We want to find all load dependencies for long chains of stores to enable
565   // merging into very wide vectors. The problem is with vectors with > 4
566   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
567   // vectors are a legal type, even though we have to split the loads
568   // usually. When we can more precisely specify load legality per address
569   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
570   // smarter so that they can figure out what to do in 2 iterations without all
571   // N > 4 stores on the same chain.
572   GatherAllAliasesMaxDepth = 16;
573 
574   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
575   // about these during lowering.
576   MaxStoresPerMemcpy  = 0xffffffff;
577   MaxStoresPerMemmove = 0xffffffff;
578   MaxStoresPerMemset  = 0xffffffff;
579 
580   setTargetDAGCombine(ISD::BITCAST);
581   setTargetDAGCombine(ISD::SHL);
582   setTargetDAGCombine(ISD::SRA);
583   setTargetDAGCombine(ISD::SRL);
584   setTargetDAGCombine(ISD::TRUNCATE);
585   setTargetDAGCombine(ISD::MUL);
586   setTargetDAGCombine(ISD::MULHU);
587   setTargetDAGCombine(ISD::MULHS);
588   setTargetDAGCombine(ISD::SELECT);
589   setTargetDAGCombine(ISD::SELECT_CC);
590   setTargetDAGCombine(ISD::STORE);
591   setTargetDAGCombine(ISD::FADD);
592   setTargetDAGCombine(ISD::FSUB);
593   setTargetDAGCombine(ISD::FNEG);
594   setTargetDAGCombine(ISD::FABS);
595   setTargetDAGCombine(ISD::AssertZext);
596   setTargetDAGCombine(ISD::AssertSext);
597 }
598 
599 //===----------------------------------------------------------------------===//
600 // Target Information
601 //===----------------------------------------------------------------------===//
602 
603 LLVM_READNONE
604 static bool fnegFoldsIntoOp(unsigned Opc) {
605   switch (Opc) {
606   case ISD::FADD:
607   case ISD::FSUB:
608   case ISD::FMUL:
609   case ISD::FMA:
610   case ISD::FMAD:
611   case ISD::FMINNUM:
612   case ISD::FMAXNUM:
613   case ISD::FSIN:
614   case ISD::FTRUNC:
615   case ISD::FRINT:
616   case ISD::FNEARBYINT:
617   case AMDGPUISD::RCP:
618   case AMDGPUISD::RCP_LEGACY:
619   case AMDGPUISD::SIN_HW:
620   case AMDGPUISD::FMUL_LEGACY:
621   case AMDGPUISD::FMIN_LEGACY:
622   case AMDGPUISD::FMAX_LEGACY:
623     return true;
624   default:
625     return false;
626   }
627 }
628 
629 /// \p returns true if the operation will definitely need to use a 64-bit
630 /// encoding, and thus will use a VOP3 encoding regardless of the source
631 /// modifiers.
632 LLVM_READONLY
633 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
634   return N->getNumOperands() > 2 || VT == MVT::f64;
635 }
636 
637 // Most FP instructions support source modifiers, but this could be refined
638 // slightly.
639 LLVM_READONLY
640 static bool hasSourceMods(const SDNode *N) {
641   if (isa<MemSDNode>(N))
642     return false;
643 
644   switch (N->getOpcode()) {
645   case ISD::CopyToReg:
646   case ISD::SELECT:
647   case ISD::FDIV:
648   case ISD::FREM:
649   case ISD::INLINEASM:
650   case AMDGPUISD::INTERP_P1:
651   case AMDGPUISD::INTERP_P2:
652   case AMDGPUISD::DIV_SCALE:
653 
654   // TODO: Should really be looking at the users of the bitcast. These are
655   // problematic because bitcasts are used to legalize all stores to integer
656   // types.
657   case ISD::BITCAST:
658     return false;
659   default:
660     return true;
661   }
662 }
663 
664 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
665                                                  unsigned CostThreshold) {
666   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
667   // it is truly free to use a source modifier in all cases. If there are
668   // multiple users but for each one will necessitate using VOP3, there will be
669   // a code size increase. Try to avoid increasing code size unless we know it
670   // will save on the instruction count.
671   unsigned NumMayIncreaseSize = 0;
672   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
673 
674   // XXX - Should this limit number of uses to check?
675   for (const SDNode *U : N->uses()) {
676     if (!hasSourceMods(U))
677       return false;
678 
679     if (!opMustUseVOP3Encoding(U, VT)) {
680       if (++NumMayIncreaseSize > CostThreshold)
681         return false;
682     }
683   }
684 
685   return true;
686 }
687 
688 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
689   return MVT::i32;
690 }
691 
692 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
693   return true;
694 }
695 
696 // The backend supports 32 and 64 bit floating point immediates.
697 // FIXME: Why are we reporting vectors of FP immediates as legal?
698 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
699   EVT ScalarVT = VT.getScalarType();
700   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
701          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
702 }
703 
704 // We don't want to shrink f64 / f32 constants.
705 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
706   EVT ScalarVT = VT.getScalarType();
707   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
708 }
709 
710 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
711                                                  ISD::LoadExtType,
712                                                  EVT NewVT) const {
713 
714   unsigned NewSize = NewVT.getStoreSizeInBits();
715 
716   // If we are reducing to a 32-bit load, this is always better.
717   if (NewSize == 32)
718     return true;
719 
720   EVT OldVT = N->getValueType(0);
721   unsigned OldSize = OldVT.getStoreSizeInBits();
722 
723   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
724   // extloads, so doing one requires using a buffer_load. In cases where we
725   // still couldn't use a scalar load, using the wider load shouldn't really
726   // hurt anything.
727 
728   // If the old size already had to be an extload, there's no harm in continuing
729   // to reduce the width.
730   return (OldSize < 32);
731 }
732 
733 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy,
734                                                    EVT CastTy) const {
735 
736   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
737 
738   if (LoadTy.getScalarType() == MVT::i32)
739     return false;
740 
741   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
742   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
743 
744   return (LScalarSize < CastScalarSize) ||
745          (CastScalarSize >= 32);
746 }
747 
748 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
749 // profitable with the expansion for 64-bit since it's generally good to
750 // speculate things.
751 // FIXME: These should really have the size as a parameter.
752 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
753   return true;
754 }
755 
756 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
757   return true;
758 }
759 
760 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
761   switch (N->getOpcode()) {
762     default:
763     return false;
764     case ISD::EntryToken:
765     case ISD::TokenFactor:
766       return true;
767     case ISD::INTRINSIC_WO_CHAIN:
768     {
769       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
770       switch (IntrID) {
771         default:
772         return false;
773         case Intrinsic::amdgcn_readfirstlane:
774         case Intrinsic::amdgcn_readlane:
775           return true;
776       }
777     }
778     break;
779     case ISD::LOAD:
780     {
781       const LoadSDNode * L = dyn_cast<LoadSDNode>(N);
782       if (L->getMemOperand()->getAddrSpace()
783       == Subtarget->getAMDGPUAS().CONSTANT_ADDRESS_32BIT)
784         return true;
785       return false;
786     }
787     break;
788   }
789 }
790 
791 //===---------------------------------------------------------------------===//
792 // Target Properties
793 //===---------------------------------------------------------------------===//
794 
795 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
796   assert(VT.isFloatingPoint());
797 
798   // Packed operations do not have a fabs modifier.
799   return VT == MVT::f32 || VT == MVT::f64 ||
800          (Subtarget->has16BitInsts() && VT == MVT::f16);
801 }
802 
803 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
804   assert(VT.isFloatingPoint());
805   return VT == MVT::f32 || VT == MVT::f64 ||
806          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
807          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
808 }
809 
810 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
811                                                          unsigned NumElem,
812                                                          unsigned AS) const {
813   return true;
814 }
815 
816 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
817   // There are few operations which truly have vector input operands. Any vector
818   // operation is going to involve operations on each component, and a
819   // build_vector will be a copy per element, so it always makes sense to use a
820   // build_vector input in place of the extracted element to avoid a copy into a
821   // super register.
822   //
823   // We should probably only do this if all users are extracts only, but this
824   // should be the common case.
825   return true;
826 }
827 
828 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
829   // Truncate is just accessing a subregister.
830 
831   unsigned SrcSize = Source.getSizeInBits();
832   unsigned DestSize = Dest.getSizeInBits();
833 
834   return DestSize < SrcSize && DestSize % 32 == 0 ;
835 }
836 
837 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
838   // Truncate is just accessing a subregister.
839 
840   unsigned SrcSize = Source->getScalarSizeInBits();
841   unsigned DestSize = Dest->getScalarSizeInBits();
842 
843   if (DestSize== 16 && Subtarget->has16BitInsts())
844     return SrcSize >= 32;
845 
846   return DestSize < SrcSize && DestSize % 32 == 0;
847 }
848 
849 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
850   unsigned SrcSize = Src->getScalarSizeInBits();
851   unsigned DestSize = Dest->getScalarSizeInBits();
852 
853   if (SrcSize == 16 && Subtarget->has16BitInsts())
854     return DestSize >= 32;
855 
856   return SrcSize == 32 && DestSize == 64;
857 }
858 
859 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
860   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
861   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
862   // this will enable reducing 64-bit operations the 32-bit, which is always
863   // good.
864 
865   if (Src == MVT::i16)
866     return Dest == MVT::i32 ||Dest == MVT::i64 ;
867 
868   return Src == MVT::i32 && Dest == MVT::i64;
869 }
870 
871 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
872   return isZExtFree(Val.getValueType(), VT2);
873 }
874 
875 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
876   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
877   // limited number of native 64-bit operations. Shrinking an operation to fit
878   // in a single 32-bit register should always be helpful. As currently used,
879   // this is much less general than the name suggests, and is only used in
880   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
881   // not profitable, and may actually be harmful.
882   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
883 }
884 
885 //===---------------------------------------------------------------------===//
886 // TargetLowering Callbacks
887 //===---------------------------------------------------------------------===//
888 
889 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
890                                                   bool IsVarArg) {
891   switch (CC) {
892   case CallingConv::AMDGPU_KERNEL:
893   case CallingConv::SPIR_KERNEL:
894     return CC_AMDGPU_Kernel;
895   case CallingConv::AMDGPU_VS:
896   case CallingConv::AMDGPU_GS:
897   case CallingConv::AMDGPU_PS:
898   case CallingConv::AMDGPU_CS:
899   case CallingConv::AMDGPU_HS:
900   case CallingConv::AMDGPU_ES:
901   case CallingConv::AMDGPU_LS:
902     return CC_AMDGPU;
903   case CallingConv::C:
904   case CallingConv::Fast:
905   case CallingConv::Cold:
906     return CC_AMDGPU_Func;
907   default:
908     report_fatal_error("Unsupported calling convention.");
909   }
910 }
911 
912 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
913                                                     bool IsVarArg) {
914   switch (CC) {
915   case CallingConv::AMDGPU_KERNEL:
916   case CallingConv::SPIR_KERNEL:
917     return CC_AMDGPU_Kernel;
918   case CallingConv::AMDGPU_VS:
919   case CallingConv::AMDGPU_GS:
920   case CallingConv::AMDGPU_PS:
921   case CallingConv::AMDGPU_CS:
922   case CallingConv::AMDGPU_HS:
923   case CallingConv::AMDGPU_ES:
924   case CallingConv::AMDGPU_LS:
925     return RetCC_SI_Shader;
926   case CallingConv::C:
927   case CallingConv::Fast:
928   case CallingConv::Cold:
929     return RetCC_AMDGPU_Func;
930   default:
931     report_fatal_error("Unsupported calling convention.");
932   }
933 }
934 
935 /// The SelectionDAGBuilder will automatically promote function arguments
936 /// with illegal types.  However, this does not work for the AMDGPU targets
937 /// since the function arguments are stored in memory as these illegal types.
938 /// In order to handle this properly we need to get the original types sizes
939 /// from the LLVM IR Function and fixup the ISD:InputArg values before
940 /// passing them to AnalyzeFormalArguments()
941 
942 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
943 /// input values across multiple registers.  Each item in the Ins array
944 /// represents a single value that will be stored in registers.  Ins[x].VT is
945 /// the value type of the value that will be stored in the register, so
946 /// whatever SDNode we lower the argument to needs to be this type.
947 ///
948 /// In order to correctly lower the arguments we need to know the size of each
949 /// argument.  Since Ins[x].VT gives us the size of the register that will
950 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
951 /// for the orignal function argument so that we can deduce the correct memory
952 /// type to use for Ins[x].  In most cases the correct memory type will be
953 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
954 /// we have a kernel argument of type v8i8, this argument will be split into
955 /// 8 parts and each part will be represented by its own item in the Ins array.
956 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
957 /// the argument before it was split.  From this, we deduce that the memory type
958 /// for each individual part is i8.  We pass the memory type as LocVT to the
959 /// calling convention analysis function and the register type (Ins[x].VT) as
960 /// the ValVT.
961 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(CCState &State,
962                              const SmallVectorImpl<ISD::InputArg> &Ins) const {
963   for (unsigned i = 0, e = Ins.size(); i != e; ++i) {
964     const ISD::InputArg &In = Ins[i];
965     EVT MemVT;
966 
967     unsigned NumRegs = getNumRegisters(State.getContext(), In.ArgVT);
968 
969     if (!Subtarget->isAmdHsaOS() &&
970         (In.ArgVT == MVT::i16 || In.ArgVT == MVT::i8 || In.ArgVT == MVT::f16)) {
971       // The ABI says the caller will extend these values to 32-bits.
972       MemVT = In.ArgVT.isInteger() ? MVT::i32 : MVT::f32;
973     } else if (NumRegs == 1) {
974       // This argument is not split, so the IR type is the memory type.
975       assert(!In.Flags.isSplit());
976       if (In.ArgVT.isExtended()) {
977         // We have an extended type, like i24, so we should just use the register type
978         MemVT = In.VT;
979       } else {
980         MemVT = In.ArgVT;
981       }
982     } else if (In.ArgVT.isVector() && In.VT.isVector() &&
983                In.ArgVT.getScalarType() == In.VT.getScalarType()) {
984       assert(In.ArgVT.getVectorNumElements() > In.VT.getVectorNumElements());
985       // We have a vector value which has been split into a vector with
986       // the same scalar type, but fewer elements.  This should handle
987       // all the floating-point vector types.
988       MemVT = In.VT;
989     } else if (In.ArgVT.isVector() &&
990                In.ArgVT.getVectorNumElements() == NumRegs) {
991       // This arg has been split so that each element is stored in a separate
992       // register.
993       MemVT = In.ArgVT.getScalarType();
994     } else if (In.ArgVT.isExtended()) {
995       // We have an extended type, like i65.
996       MemVT = In.VT;
997     } else {
998       unsigned MemoryBits = In.ArgVT.getStoreSizeInBits() / NumRegs;
999       assert(In.ArgVT.getStoreSizeInBits() % NumRegs == 0);
1000       if (In.VT.isInteger()) {
1001         MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
1002       } else if (In.VT.isVector()) {
1003         assert(!In.VT.getScalarType().isFloatingPoint());
1004         unsigned NumElements = In.VT.getVectorNumElements();
1005         assert(MemoryBits % NumElements == 0);
1006         // This vector type has been split into another vector type with
1007         // a different elements size.
1008         EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
1009                                          MemoryBits / NumElements);
1010         MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
1011       } else {
1012         llvm_unreachable("cannot deduce memory type.");
1013       }
1014     }
1015 
1016     // Convert one element vectors to scalar.
1017     if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
1018       MemVT = MemVT.getScalarType();
1019 
1020     if (MemVT.isExtended()) {
1021       // This should really only happen if we have vec3 arguments
1022       assert(MemVT.isVector() && MemVT.getVectorNumElements() == 3);
1023       MemVT = MemVT.getPow2VectorType(State.getContext());
1024     }
1025 
1026     assert(MemVT.isSimple());
1027     allocateKernArg(i, In.VT, MemVT.getSimpleVT(), CCValAssign::Full, In.Flags,
1028                     State);
1029   }
1030 }
1031 
1032 SDValue AMDGPUTargetLowering::LowerReturn(
1033   SDValue Chain, CallingConv::ID CallConv,
1034   bool isVarArg,
1035   const SmallVectorImpl<ISD::OutputArg> &Outs,
1036   const SmallVectorImpl<SDValue> &OutVals,
1037   const SDLoc &DL, SelectionDAG &DAG) const {
1038   // FIXME: Fails for r600 tests
1039   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1040   // "wave terminate should not have return values");
1041   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1042 }
1043 
1044 //===---------------------------------------------------------------------===//
1045 // Target specific lowering
1046 //===---------------------------------------------------------------------===//
1047 
1048 /// Selects the correct CCAssignFn for a given CallingConvention value.
1049 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1050                                                     bool IsVarArg) {
1051   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1052 }
1053 
1054 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1055                                                       bool IsVarArg) {
1056   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1057 }
1058 
1059 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1060                                                   SelectionDAG &DAG,
1061                                                   MachineFrameInfo &MFI,
1062                                                   int ClobberedFI) const {
1063   SmallVector<SDValue, 8> ArgChains;
1064   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1065   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1066 
1067   // Include the original chain at the beginning of the list. When this is
1068   // used by target LowerCall hooks, this helps legalize find the
1069   // CALLSEQ_BEGIN node.
1070   ArgChains.push_back(Chain);
1071 
1072   // Add a chain value for each stack argument corresponding
1073   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1074                             UE = DAG.getEntryNode().getNode()->use_end();
1075        U != UE; ++U) {
1076     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1077       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1078         if (FI->getIndex() < 0) {
1079           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1080           int64_t InLastByte = InFirstByte;
1081           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1082 
1083           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1084               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1085             ArgChains.push_back(SDValue(L, 1));
1086         }
1087       }
1088     }
1089   }
1090 
1091   // Build a tokenfactor for all the chains.
1092   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1093 }
1094 
1095 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1096                                                  SmallVectorImpl<SDValue> &InVals,
1097                                                  StringRef Reason) const {
1098   SDValue Callee = CLI.Callee;
1099   SelectionDAG &DAG = CLI.DAG;
1100 
1101   const Function &Fn = DAG.getMachineFunction().getFunction();
1102 
1103   StringRef FuncName("<unknown>");
1104 
1105   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1106     FuncName = G->getSymbol();
1107   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1108     FuncName = G->getGlobal()->getName();
1109 
1110   DiagnosticInfoUnsupported NoCalls(
1111     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1112   DAG.getContext()->diagnose(NoCalls);
1113 
1114   if (!CLI.IsTailCall) {
1115     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1116       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1117   }
1118 
1119   return DAG.getEntryNode();
1120 }
1121 
1122 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1123                                         SmallVectorImpl<SDValue> &InVals) const {
1124   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1125 }
1126 
1127 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1128                                                       SelectionDAG &DAG) const {
1129   const Function &Fn = DAG.getMachineFunction().getFunction();
1130 
1131   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1132                                             SDLoc(Op).getDebugLoc());
1133   DAG.getContext()->diagnose(NoDynamicAlloca);
1134   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1135   return DAG.getMergeValues(Ops, SDLoc());
1136 }
1137 
1138 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1139                                              SelectionDAG &DAG) const {
1140   switch (Op.getOpcode()) {
1141   default:
1142     Op->print(errs(), &DAG);
1143     llvm_unreachable("Custom lowering code for this"
1144                      "instruction is not implemented yet!");
1145     break;
1146   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1147   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1148   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1149   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1150   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1151   case ISD::FREM: return LowerFREM(Op, DAG);
1152   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1153   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1154   case ISD::FRINT: return LowerFRINT(Op, DAG);
1155   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1156   case ISD::FROUND: return LowerFROUND(Op, DAG);
1157   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1158   case ISD::FLOG:
1159     return LowerFLOG(Op, DAG, 1 / AMDGPU_LOG2E_F);
1160   case ISD::FLOG10:
1161     return LowerFLOG(Op, DAG, AMDGPU_LN2_F / AMDGPU_LN10_F);
1162   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1163   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1164   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1165   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1166   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1167   case ISD::CTTZ:
1168   case ISD::CTTZ_ZERO_UNDEF:
1169   case ISD::CTLZ:
1170   case ISD::CTLZ_ZERO_UNDEF:
1171     return LowerCTLZ_CTTZ(Op, DAG);
1172   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1173   }
1174   return Op;
1175 }
1176 
1177 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1178                                               SmallVectorImpl<SDValue> &Results,
1179                                               SelectionDAG &DAG) const {
1180   switch (N->getOpcode()) {
1181   case ISD::SIGN_EXTEND_INREG:
1182     // Different parts of legalization seem to interpret which type of
1183     // sign_extend_inreg is the one to check for custom lowering. The extended
1184     // from type is what really matters, but some places check for custom
1185     // lowering of the result type. This results in trying to use
1186     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1187     // nothing here and let the illegal result integer be handled normally.
1188     return;
1189   default:
1190     return;
1191   }
1192 }
1193 
1194 static bool hasDefinedInitializer(const GlobalValue *GV) {
1195   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1196   if (!GVar || !GVar->hasInitializer())
1197     return false;
1198 
1199   return !isa<UndefValue>(GVar->getInitializer());
1200 }
1201 
1202 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1203                                                  SDValue Op,
1204                                                  SelectionDAG &DAG) const {
1205 
1206   const DataLayout &DL = DAG.getDataLayout();
1207   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1208   const GlobalValue *GV = G->getGlobal();
1209 
1210   if (G->getAddressSpace() == AMDGPUASI.LOCAL_ADDRESS ||
1211       G->getAddressSpace() == AMDGPUASI.REGION_ADDRESS) {
1212     if (!MFI->isEntryFunction()) {
1213       const Function &Fn = DAG.getMachineFunction().getFunction();
1214       DiagnosticInfoUnsupported BadLDSDecl(
1215         Fn, "local memory global used by non-kernel function", SDLoc(Op).getDebugLoc());
1216       DAG.getContext()->diagnose(BadLDSDecl);
1217     }
1218 
1219     // XXX: What does the value of G->getOffset() mean?
1220     assert(G->getOffset() == 0 &&
1221          "Do not know what to do with an non-zero offset");
1222 
1223     // TODO: We could emit code to handle the initialization somewhere.
1224     if (!hasDefinedInitializer(GV)) {
1225       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1226       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1227     }
1228   }
1229 
1230   const Function &Fn = DAG.getMachineFunction().getFunction();
1231   DiagnosticInfoUnsupported BadInit(
1232       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1233   DAG.getContext()->diagnose(BadInit);
1234   return SDValue();
1235 }
1236 
1237 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1238                                                   SelectionDAG &DAG) const {
1239   SmallVector<SDValue, 8> Args;
1240 
1241   EVT VT = Op.getValueType();
1242   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1243     SDLoc SL(Op);
1244     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1245     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1246 
1247     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1248     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1249   }
1250 
1251   for (const SDUse &U : Op->ops())
1252     DAG.ExtractVectorElements(U.get(), Args);
1253 
1254   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1255 }
1256 
1257 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1258                                                      SelectionDAG &DAG) const {
1259 
1260   SmallVector<SDValue, 8> Args;
1261   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1262   EVT VT = Op.getValueType();
1263   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1264                             VT.getVectorNumElements());
1265 
1266   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1267 }
1268 
1269 /// Generate Min/Max node
1270 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1271                                                    SDValue LHS, SDValue RHS,
1272                                                    SDValue True, SDValue False,
1273                                                    SDValue CC,
1274                                                    DAGCombinerInfo &DCI) const {
1275   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1276     return SDValue();
1277 
1278   SelectionDAG &DAG = DCI.DAG;
1279   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1280   switch (CCOpcode) {
1281   case ISD::SETOEQ:
1282   case ISD::SETONE:
1283   case ISD::SETUNE:
1284   case ISD::SETNE:
1285   case ISD::SETUEQ:
1286   case ISD::SETEQ:
1287   case ISD::SETFALSE:
1288   case ISD::SETFALSE2:
1289   case ISD::SETTRUE:
1290   case ISD::SETTRUE2:
1291   case ISD::SETUO:
1292   case ISD::SETO:
1293     break;
1294   case ISD::SETULE:
1295   case ISD::SETULT: {
1296     if (LHS == True)
1297       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1298     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1299   }
1300   case ISD::SETOLE:
1301   case ISD::SETOLT:
1302   case ISD::SETLE:
1303   case ISD::SETLT: {
1304     // Ordered. Assume ordered for undefined.
1305 
1306     // Only do this after legalization to avoid interfering with other combines
1307     // which might occur.
1308     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1309         !DCI.isCalledByLegalizer())
1310       return SDValue();
1311 
1312     // We need to permute the operands to get the correct NaN behavior. The
1313     // selected operand is the second one based on the failing compare with NaN,
1314     // so permute it based on the compare type the hardware uses.
1315     if (LHS == True)
1316       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1317     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1318   }
1319   case ISD::SETUGE:
1320   case ISD::SETUGT: {
1321     if (LHS == True)
1322       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1323     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1324   }
1325   case ISD::SETGT:
1326   case ISD::SETGE:
1327   case ISD::SETOGE:
1328   case ISD::SETOGT: {
1329     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1330         !DCI.isCalledByLegalizer())
1331       return SDValue();
1332 
1333     if (LHS == True)
1334       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1335     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1336   }
1337   case ISD::SETCC_INVALID:
1338     llvm_unreachable("Invalid setcc condcode!");
1339   }
1340   return SDValue();
1341 }
1342 
1343 std::pair<SDValue, SDValue>
1344 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1345   SDLoc SL(Op);
1346 
1347   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1348 
1349   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1350   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1351 
1352   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1353   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1354 
1355   return std::make_pair(Lo, Hi);
1356 }
1357 
1358 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1359   SDLoc SL(Op);
1360 
1361   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1362   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1363   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1364 }
1365 
1366 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1367   SDLoc SL(Op);
1368 
1369   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1370   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1371   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1372 }
1373 
1374 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1375                                               SelectionDAG &DAG) const {
1376   LoadSDNode *Load = cast<LoadSDNode>(Op);
1377   EVT VT = Op.getValueType();
1378 
1379 
1380   // If this is a 2 element vector, we really want to scalarize and not create
1381   // weird 1 element vectors.
1382   if (VT.getVectorNumElements() == 2)
1383     return scalarizeVectorLoad(Load, DAG);
1384 
1385   SDValue BasePtr = Load->getBasePtr();
1386   EVT MemVT = Load->getMemoryVT();
1387   SDLoc SL(Op);
1388 
1389   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1390 
1391   EVT LoVT, HiVT;
1392   EVT LoMemVT, HiMemVT;
1393   SDValue Lo, Hi;
1394 
1395   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1396   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1397   std::tie(Lo, Hi) = DAG.SplitVector(Op, SL, LoVT, HiVT);
1398 
1399   unsigned Size = LoMemVT.getStoreSize();
1400   unsigned BaseAlign = Load->getAlignment();
1401   unsigned HiAlign = MinAlign(BaseAlign, Size);
1402 
1403   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1404                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1405                                   BaseAlign, Load->getMemOperand()->getFlags());
1406   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1407   SDValue HiLoad =
1408       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1409                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1410                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1411 
1412   SDValue Ops[] = {
1413     DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad),
1414     DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1415                 LoLoad.getValue(1), HiLoad.getValue(1))
1416   };
1417 
1418   return DAG.getMergeValues(Ops, SL);
1419 }
1420 
1421 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1422                                                SelectionDAG &DAG) const {
1423   StoreSDNode *Store = cast<StoreSDNode>(Op);
1424   SDValue Val = Store->getValue();
1425   EVT VT = Val.getValueType();
1426 
1427   // If this is a 2 element vector, we really want to scalarize and not create
1428   // weird 1 element vectors.
1429   if (VT.getVectorNumElements() == 2)
1430     return scalarizeVectorStore(Store, DAG);
1431 
1432   EVT MemVT = Store->getMemoryVT();
1433   SDValue Chain = Store->getChain();
1434   SDValue BasePtr = Store->getBasePtr();
1435   SDLoc SL(Op);
1436 
1437   EVT LoVT, HiVT;
1438   EVT LoMemVT, HiMemVT;
1439   SDValue Lo, Hi;
1440 
1441   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1442   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1443   std::tie(Lo, Hi) = DAG.SplitVector(Val, SL, LoVT, HiVT);
1444 
1445   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1446 
1447   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1448   unsigned BaseAlign = Store->getAlignment();
1449   unsigned Size = LoMemVT.getStoreSize();
1450   unsigned HiAlign = MinAlign(BaseAlign, Size);
1451 
1452   SDValue LoStore =
1453       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1454                         Store->getMemOperand()->getFlags());
1455   SDValue HiStore =
1456       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1457                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1458 
1459   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1460 }
1461 
1462 // This is a shortcut for integer division because we have fast i32<->f32
1463 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1464 // float is enough to accurately represent up to a 24-bit signed integer.
1465 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1466                                             bool Sign) const {
1467   SDLoc DL(Op);
1468   EVT VT = Op.getValueType();
1469   SDValue LHS = Op.getOperand(0);
1470   SDValue RHS = Op.getOperand(1);
1471   MVT IntVT = MVT::i32;
1472   MVT FltVT = MVT::f32;
1473 
1474   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1475   if (LHSSignBits < 9)
1476     return SDValue();
1477 
1478   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1479   if (RHSSignBits < 9)
1480     return SDValue();
1481 
1482   unsigned BitSize = VT.getSizeInBits();
1483   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1484   unsigned DivBits = BitSize - SignBits;
1485   if (Sign)
1486     ++DivBits;
1487 
1488   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1489   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1490 
1491   SDValue jq = DAG.getConstant(1, DL, IntVT);
1492 
1493   if (Sign) {
1494     // char|short jq = ia ^ ib;
1495     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1496 
1497     // jq = jq >> (bitsize - 2)
1498     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1499                      DAG.getConstant(BitSize - 2, DL, VT));
1500 
1501     // jq = jq | 0x1
1502     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1503   }
1504 
1505   // int ia = (int)LHS;
1506   SDValue ia = LHS;
1507 
1508   // int ib, (int)RHS;
1509   SDValue ib = RHS;
1510 
1511   // float fa = (float)ia;
1512   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1513 
1514   // float fb = (float)ib;
1515   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1516 
1517   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1518                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1519 
1520   // fq = trunc(fq);
1521   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1522 
1523   // float fqneg = -fq;
1524   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1525 
1526   // float fr = mad(fqneg, fb, fa);
1527   unsigned OpCode = Subtarget->hasFP32Denormals() ?
1528                     (unsigned)AMDGPUISD::FMAD_FTZ :
1529                     (unsigned)ISD::FMAD;
1530   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1531 
1532   // int iq = (int)fq;
1533   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1534 
1535   // fr = fabs(fr);
1536   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1537 
1538   // fb = fabs(fb);
1539   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1540 
1541   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1542 
1543   // int cv = fr >= fb;
1544   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1545 
1546   // jq = (cv ? jq : 0);
1547   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1548 
1549   // dst = iq + jq;
1550   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1551 
1552   // Rem needs compensation, it's easier to recompute it
1553   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1554   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1555 
1556   // Truncate to number of bits this divide really is.
1557   if (Sign) {
1558     SDValue InRegSize
1559       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1560     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1561     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1562   } else {
1563     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1564     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1565     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1566   }
1567 
1568   return DAG.getMergeValues({ Div, Rem }, DL);
1569 }
1570 
1571 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1572                                       SelectionDAG &DAG,
1573                                       SmallVectorImpl<SDValue> &Results) const {
1574   SDLoc DL(Op);
1575   EVT VT = Op.getValueType();
1576 
1577   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1578 
1579   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1580 
1581   SDValue One = DAG.getConstant(1, DL, HalfVT);
1582   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1583 
1584   //HiLo split
1585   SDValue LHS = Op.getOperand(0);
1586   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1587   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1588 
1589   SDValue RHS = Op.getOperand(1);
1590   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1591   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1592 
1593   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1594       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1595 
1596     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1597                               LHS_Lo, RHS_Lo);
1598 
1599     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1600     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1601 
1602     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1603     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1604     return;
1605   }
1606 
1607   if (isTypeLegal(MVT::i64)) {
1608     // Compute denominator reciprocal.
1609     unsigned FMAD = Subtarget->hasFP32Denormals() ?
1610                     (unsigned)AMDGPUISD::FMAD_FTZ :
1611                     (unsigned)ISD::FMAD;
1612 
1613     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1614     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1615     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1616       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1617       Cvt_Lo);
1618     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1619     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1620       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1621     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1622       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1623     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1624     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1625       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1626       Mul1);
1627     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1628     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1629     SDValue Rcp64 = DAG.getBitcast(VT,
1630                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1631 
1632     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1633     SDValue One64  = DAG.getConstant(1, DL, VT);
1634     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1635     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1636 
1637     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1638     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1639     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1640     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1641                                     Zero);
1642     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1643                                     One);
1644 
1645     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1646                                   Mulhi1_Lo, Zero1);
1647     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1648                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1649     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1650     SDValue Add1 = DAG.getBitcast(VT,
1651                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1652 
1653     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1654     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1655     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1656                                     Zero);
1657     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1658                                     One);
1659 
1660     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1661                                   Mulhi2_Lo, Zero1);
1662     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1663                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1664     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1665                                   Zero, Add2_Lo.getValue(1));
1666     SDValue Add2 = DAG.getBitcast(VT,
1667                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1668     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1669 
1670     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1671 
1672     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1673     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1674     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1675                                   Mul3_Lo, Zero1);
1676     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1677                                   Mul3_Hi, Sub1_Lo.getValue(1));
1678     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1679     SDValue Sub1 = DAG.getBitcast(VT,
1680                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1681 
1682     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1683     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1684                                  ISD::SETUGE);
1685     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1686                                  ISD::SETUGE);
1687     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1688 
1689     // TODO: Here and below portions of the code can be enclosed into if/endif.
1690     // Currently control flow is unconditional and we have 4 selects after
1691     // potential endif to substitute PHIs.
1692 
1693     // if C3 != 0 ...
1694     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1695                                   RHS_Lo, Zero1);
1696     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1697                                   RHS_Hi, Sub1_Lo.getValue(1));
1698     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1699                                   Zero, Sub2_Lo.getValue(1));
1700     SDValue Sub2 = DAG.getBitcast(VT,
1701                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1702 
1703     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1704 
1705     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1706                                  ISD::SETUGE);
1707     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1708                                  ISD::SETUGE);
1709     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1710 
1711     // if (C6 != 0)
1712     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1713 
1714     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1715                                   RHS_Lo, Zero1);
1716     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1717                                   RHS_Hi, Sub2_Lo.getValue(1));
1718     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1719                                   Zero, Sub3_Lo.getValue(1));
1720     SDValue Sub3 = DAG.getBitcast(VT,
1721                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1722 
1723     // endif C6
1724     // endif C3
1725 
1726     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1727     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1728 
1729     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1730     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1731 
1732     Results.push_back(Div);
1733     Results.push_back(Rem);
1734 
1735     return;
1736   }
1737 
1738   // r600 expandion.
1739   // Get Speculative values
1740   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1741   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1742 
1743   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1744   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1745   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1746 
1747   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1748   SDValue DIV_Lo = Zero;
1749 
1750   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1751 
1752   for (unsigned i = 0; i < halfBitWidth; ++i) {
1753     const unsigned bitPos = halfBitWidth - i - 1;
1754     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1755     // Get value of high bit
1756     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1757     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1758     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1759 
1760     // Shift
1761     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1762     // Add LHS high bit
1763     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1764 
1765     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1766     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1767 
1768     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1769 
1770     // Update REM
1771     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1772     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1773   }
1774 
1775   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1776   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1777   Results.push_back(DIV);
1778   Results.push_back(REM);
1779 }
1780 
1781 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1782                                            SelectionDAG &DAG) const {
1783   SDLoc DL(Op);
1784   EVT VT = Op.getValueType();
1785 
1786   if (VT == MVT::i64) {
1787     SmallVector<SDValue, 2> Results;
1788     LowerUDIVREM64(Op, DAG, Results);
1789     return DAG.getMergeValues(Results, DL);
1790   }
1791 
1792   if (VT == MVT::i32) {
1793     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1794       return Res;
1795   }
1796 
1797   SDValue Num = Op.getOperand(0);
1798   SDValue Den = Op.getOperand(1);
1799 
1800   // RCP =  URECIP(Den) = 2^32 / Den + e
1801   // e is rounding error.
1802   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1803 
1804   // RCP_LO = mul(RCP, Den) */
1805   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1806 
1807   // RCP_HI = mulhu (RCP, Den) */
1808   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1809 
1810   // NEG_RCP_LO = -RCP_LO
1811   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1812                                                      RCP_LO);
1813 
1814   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1815   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1816                                            NEG_RCP_LO, RCP_LO,
1817                                            ISD::SETEQ);
1818   // Calculate the rounding error from the URECIP instruction
1819   // E = mulhu(ABS_RCP_LO, RCP)
1820   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1821 
1822   // RCP_A_E = RCP + E
1823   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1824 
1825   // RCP_S_E = RCP - E
1826   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1827 
1828   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1829   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1830                                      RCP_A_E, RCP_S_E,
1831                                      ISD::SETEQ);
1832   // Quotient = mulhu(Tmp0, Num)
1833   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1834 
1835   // Num_S_Remainder = Quotient * Den
1836   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1837 
1838   // Remainder = Num - Num_S_Remainder
1839   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1840 
1841   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1842   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1843                                                  DAG.getConstant(-1, DL, VT),
1844                                                  DAG.getConstant(0, DL, VT),
1845                                                  ISD::SETUGE);
1846   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1847   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1848                                                   Num_S_Remainder,
1849                                                   DAG.getConstant(-1, DL, VT),
1850                                                   DAG.getConstant(0, DL, VT),
1851                                                   ISD::SETUGE);
1852   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1853   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1854                                                Remainder_GE_Zero);
1855 
1856   // Calculate Division result:
1857 
1858   // Quotient_A_One = Quotient + 1
1859   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1860                                        DAG.getConstant(1, DL, VT));
1861 
1862   // Quotient_S_One = Quotient - 1
1863   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1864                                        DAG.getConstant(1, DL, VT));
1865 
1866   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1867   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1868                                      Quotient, Quotient_A_One, ISD::SETEQ);
1869 
1870   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1871   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1872                             Quotient_S_One, Div, ISD::SETEQ);
1873 
1874   // Calculate Rem result:
1875 
1876   // Remainder_S_Den = Remainder - Den
1877   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1878 
1879   // Remainder_A_Den = Remainder + Den
1880   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1881 
1882   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1883   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1884                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1885 
1886   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1887   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1888                             Remainder_A_Den, Rem, ISD::SETEQ);
1889   SDValue Ops[2] = {
1890     Div,
1891     Rem
1892   };
1893   return DAG.getMergeValues(Ops, DL);
1894 }
1895 
1896 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
1897                                            SelectionDAG &DAG) const {
1898   SDLoc DL(Op);
1899   EVT VT = Op.getValueType();
1900 
1901   SDValue LHS = Op.getOperand(0);
1902   SDValue RHS = Op.getOperand(1);
1903 
1904   SDValue Zero = DAG.getConstant(0, DL, VT);
1905   SDValue NegOne = DAG.getConstant(-1, DL, VT);
1906 
1907   if (VT == MVT::i32) {
1908     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
1909       return Res;
1910   }
1911 
1912   if (VT == MVT::i64 &&
1913       DAG.ComputeNumSignBits(LHS) > 32 &&
1914       DAG.ComputeNumSignBits(RHS) > 32) {
1915     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1916 
1917     //HiLo split
1918     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1919     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1920     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1921                                  LHS_Lo, RHS_Lo);
1922     SDValue Res[2] = {
1923       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
1924       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
1925     };
1926     return DAG.getMergeValues(Res, DL);
1927   }
1928 
1929   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
1930   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
1931   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
1932   SDValue RSign = LHSign; // Remainder sign is the same as LHS
1933 
1934   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
1935   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
1936 
1937   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
1938   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
1939 
1940   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
1941   SDValue Rem = Div.getValue(1);
1942 
1943   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
1944   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
1945 
1946   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
1947   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
1948 
1949   SDValue Res[2] = {
1950     Div,
1951     Rem
1952   };
1953   return DAG.getMergeValues(Res, DL);
1954 }
1955 
1956 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
1957 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
1958   SDLoc SL(Op);
1959   EVT VT = Op.getValueType();
1960   SDValue X = Op.getOperand(0);
1961   SDValue Y = Op.getOperand(1);
1962 
1963   // TODO: Should this propagate fast-math-flags?
1964 
1965   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
1966   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
1967   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
1968 
1969   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
1970 }
1971 
1972 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
1973   SDLoc SL(Op);
1974   SDValue Src = Op.getOperand(0);
1975 
1976   // result = trunc(src)
1977   // if (src > 0.0 && src != result)
1978   //   result += 1.0
1979 
1980   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
1981 
1982   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
1983   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
1984 
1985   EVT SetCCVT =
1986       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
1987 
1988   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
1989   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
1990   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
1991 
1992   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
1993   // TODO: Should this propagate fast-math-flags?
1994   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
1995 }
1996 
1997 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
1998                                   SelectionDAG &DAG) {
1999   const unsigned FractBits = 52;
2000   const unsigned ExpBits = 11;
2001 
2002   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
2003                                 Hi,
2004                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
2005                                 DAG.getConstant(ExpBits, SL, MVT::i32));
2006   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
2007                             DAG.getConstant(1023, SL, MVT::i32));
2008 
2009   return Exp;
2010 }
2011 
2012 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2013   SDLoc SL(Op);
2014   SDValue Src = Op.getOperand(0);
2015 
2016   assert(Op.getValueType() == MVT::f64);
2017 
2018   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2019   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2020 
2021   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2022 
2023   // Extract the upper half, since this is where we will find the sign and
2024   // exponent.
2025   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2026 
2027   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2028 
2029   const unsigned FractBits = 52;
2030 
2031   // Extract the sign bit.
2032   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2033   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2034 
2035   // Extend back to 64-bits.
2036   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2037   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2038 
2039   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2040   const SDValue FractMask
2041     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2042 
2043   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2044   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2045   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2046 
2047   EVT SetCCVT =
2048       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2049 
2050   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2051 
2052   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2053   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2054 
2055   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2056   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2057 
2058   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2059 }
2060 
2061 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2062   SDLoc SL(Op);
2063   SDValue Src = Op.getOperand(0);
2064 
2065   assert(Op.getValueType() == MVT::f64);
2066 
2067   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2068   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2069   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2070 
2071   // TODO: Should this propagate fast-math-flags?
2072 
2073   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2074   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2075 
2076   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2077 
2078   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2079   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2080 
2081   EVT SetCCVT =
2082       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2083   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2084 
2085   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2086 }
2087 
2088 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2089   // FNEARBYINT and FRINT are the same, except in their handling of FP
2090   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2091   // rint, so just treat them as equivalent.
2092   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2093 }
2094 
2095 // XXX - May require not supporting f32 denormals?
2096 
2097 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2098 // compare and vselect end up producing worse code than scalarizing the whole
2099 // operation.
2100 SDValue AMDGPUTargetLowering::LowerFROUND32_16(SDValue Op, SelectionDAG &DAG) const {
2101   SDLoc SL(Op);
2102   SDValue X = Op.getOperand(0);
2103   EVT VT = Op.getValueType();
2104 
2105   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2106 
2107   // TODO: Should this propagate fast-math-flags?
2108 
2109   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2110 
2111   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2112 
2113   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2114   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2115   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2116 
2117   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2118 
2119   EVT SetCCVT =
2120       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2121 
2122   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2123 
2124   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2125 
2126   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2127 }
2128 
2129 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
2130   SDLoc SL(Op);
2131   SDValue X = Op.getOperand(0);
2132 
2133   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
2134 
2135   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2136   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2137   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
2138   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
2139   EVT SetCCVT =
2140       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2141 
2142   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
2143 
2144   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
2145 
2146   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2147 
2148   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
2149                                        MVT::i64);
2150 
2151   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
2152   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
2153                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
2154                                           MVT::i64),
2155                           Exp);
2156 
2157   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
2158   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
2159                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
2160                               ISD::SETNE);
2161 
2162   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
2163                              D, DAG.getConstant(0, SL, MVT::i64));
2164   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
2165 
2166   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
2167   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
2168 
2169   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2170   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2171   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
2172 
2173   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
2174                             ExpEqNegOne,
2175                             DAG.getConstantFP(1.0, SL, MVT::f64),
2176                             DAG.getConstantFP(0.0, SL, MVT::f64));
2177 
2178   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
2179 
2180   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
2181   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
2182 
2183   return K;
2184 }
2185 
2186 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2187   EVT VT = Op.getValueType();
2188 
2189   if (VT == MVT::f32 || VT == MVT::f16)
2190     return LowerFROUND32_16(Op, DAG);
2191 
2192   if (VT == MVT::f64)
2193     return LowerFROUND64(Op, DAG);
2194 
2195   llvm_unreachable("unhandled type");
2196 }
2197 
2198 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2199   SDLoc SL(Op);
2200   SDValue Src = Op.getOperand(0);
2201 
2202   // result = trunc(src);
2203   // if (src < 0.0 && src != result)
2204   //   result += -1.0.
2205 
2206   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2207 
2208   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2209   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2210 
2211   EVT SetCCVT =
2212       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2213 
2214   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2215   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2216   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2217 
2218   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2219   // TODO: Should this propagate fast-math-flags?
2220   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2221 }
2222 
2223 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2224                                         double Log2BaseInverted) const {
2225   EVT VT = Op.getValueType();
2226 
2227   SDLoc SL(Op);
2228   SDValue Operand = Op.getOperand(0);
2229   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2230   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2231 
2232   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2233 }
2234 
2235 static bool isCtlzOpc(unsigned Opc) {
2236   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2237 }
2238 
2239 static bool isCttzOpc(unsigned Opc) {
2240   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2241 }
2242 
2243 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2244   SDLoc SL(Op);
2245   SDValue Src = Op.getOperand(0);
2246   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2247                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2248 
2249   unsigned ISDOpc, NewOpc;
2250   if (isCtlzOpc(Op.getOpcode())) {
2251     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2252     NewOpc = AMDGPUISD::FFBH_U32;
2253   } else if (isCttzOpc(Op.getOpcode())) {
2254     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2255     NewOpc = AMDGPUISD::FFBL_B32;
2256   } else
2257     llvm_unreachable("Unexpected OPCode!!!");
2258 
2259 
2260   if (ZeroUndef && Src.getValueType() == MVT::i32)
2261     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2262 
2263   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2264 
2265   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2266   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2267 
2268   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2269   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2270 
2271   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2272                                    *DAG.getContext(), MVT::i32);
2273 
2274   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2275   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2276 
2277   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2278   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2279 
2280   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2281   SDValue Add, NewOpr;
2282   if (isCtlzOpc(Op.getOpcode())) {
2283     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2284     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2285     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2286   } else {
2287     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2288     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2289     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2290   }
2291 
2292   if (!ZeroUndef) {
2293     // Test if the full 64-bit input is zero.
2294 
2295     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2296     // which we probably don't want.
2297     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2298     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2299     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2300 
2301     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2302     // with the same cycles, otherwise it is slower.
2303     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2304     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2305 
2306     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2307 
2308     // The instruction returns -1 for 0 input, but the defined intrinsic
2309     // behavior is to return the number of bits.
2310     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2311                          SrcIsZero, Bits32, NewOpr);
2312   }
2313 
2314   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2315 }
2316 
2317 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2318                                                bool Signed) const {
2319   // Unsigned
2320   // cul2f(ulong u)
2321   //{
2322   //  uint lz = clz(u);
2323   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2324   //  u = (u << lz) & 0x7fffffffffffffffUL;
2325   //  ulong t = u & 0xffffffffffUL;
2326   //  uint v = (e << 23) | (uint)(u >> 40);
2327   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2328   //  return as_float(v + r);
2329   //}
2330   // Signed
2331   // cl2f(long l)
2332   //{
2333   //  long s = l >> 63;
2334   //  float r = cul2f((l + s) ^ s);
2335   //  return s ? -r : r;
2336   //}
2337 
2338   SDLoc SL(Op);
2339   SDValue Src = Op.getOperand(0);
2340   SDValue L = Src;
2341 
2342   SDValue S;
2343   if (Signed) {
2344     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2345     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2346 
2347     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2348     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2349   }
2350 
2351   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2352                                    *DAG.getContext(), MVT::f32);
2353 
2354 
2355   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2356   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2357   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2358   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2359 
2360   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2361   SDValue E = DAG.getSelect(SL, MVT::i32,
2362     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2363     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2364     ZeroI32);
2365 
2366   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2367     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2368     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2369 
2370   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2371                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2372 
2373   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2374                              U, DAG.getConstant(40, SL, MVT::i64));
2375 
2376   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2377     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2378     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2379 
2380   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2381   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2382   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2383 
2384   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2385 
2386   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2387 
2388   SDValue R = DAG.getSelect(SL, MVT::i32,
2389     RCmp,
2390     One,
2391     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2392   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2393   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2394 
2395   if (!Signed)
2396     return R;
2397 
2398   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2399   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2400 }
2401 
2402 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2403                                                bool Signed) const {
2404   SDLoc SL(Op);
2405   SDValue Src = Op.getOperand(0);
2406 
2407   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2408 
2409   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2410                            DAG.getConstant(0, SL, MVT::i32));
2411   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2412                            DAG.getConstant(1, SL, MVT::i32));
2413 
2414   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2415                               SL, MVT::f64, Hi);
2416 
2417   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2418 
2419   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2420                               DAG.getConstant(32, SL, MVT::i32));
2421   // TODO: Should this propagate fast-math-flags?
2422   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2423 }
2424 
2425 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2426                                                SelectionDAG &DAG) const {
2427   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2428          "operation should be legal");
2429 
2430   // TODO: Factor out code common with LowerSINT_TO_FP.
2431 
2432   EVT DestVT = Op.getValueType();
2433   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2434     SDLoc DL(Op);
2435     SDValue Src = Op.getOperand(0);
2436 
2437     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2438     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2439     SDValue FPRound =
2440         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2441 
2442     return FPRound;
2443   }
2444 
2445   if (DestVT == MVT::f32)
2446     return LowerINT_TO_FP32(Op, DAG, false);
2447 
2448   assert(DestVT == MVT::f64);
2449   return LowerINT_TO_FP64(Op, DAG, false);
2450 }
2451 
2452 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2453                                               SelectionDAG &DAG) const {
2454   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2455          "operation should be legal");
2456 
2457   // TODO: Factor out code common with LowerUINT_TO_FP.
2458 
2459   EVT DestVT = Op.getValueType();
2460   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2461     SDLoc DL(Op);
2462     SDValue Src = Op.getOperand(0);
2463 
2464     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2465     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2466     SDValue FPRound =
2467         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2468 
2469     return FPRound;
2470   }
2471 
2472   if (DestVT == MVT::f32)
2473     return LowerINT_TO_FP32(Op, DAG, true);
2474 
2475   assert(DestVT == MVT::f64);
2476   return LowerINT_TO_FP64(Op, DAG, true);
2477 }
2478 
2479 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2480                                                bool Signed) const {
2481   SDLoc SL(Op);
2482 
2483   SDValue Src = Op.getOperand(0);
2484 
2485   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2486 
2487   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2488                                  MVT::f64);
2489   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2490                                  MVT::f64);
2491   // TODO: Should this propagate fast-math-flags?
2492   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2493 
2494   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2495 
2496 
2497   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2498 
2499   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2500                            MVT::i32, FloorMul);
2501   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2502 
2503   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2504 
2505   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2506 }
2507 
2508 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2509   SDLoc DL(Op);
2510   SDValue N0 = Op.getOperand(0);
2511 
2512   // Convert to target node to get known bits
2513   if (N0.getValueType() == MVT::f32)
2514     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2515 
2516   if (getTargetMachine().Options.UnsafeFPMath) {
2517     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2518     return SDValue();
2519   }
2520 
2521   assert(N0.getSimpleValueType() == MVT::f64);
2522 
2523   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2524   const unsigned ExpMask = 0x7ff;
2525   const unsigned ExpBiasf64 = 1023;
2526   const unsigned ExpBiasf16 = 15;
2527   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2528   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2529   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2530   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2531                            DAG.getConstant(32, DL, MVT::i64));
2532   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2533   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2534   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2535                           DAG.getConstant(20, DL, MVT::i64));
2536   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2537                   DAG.getConstant(ExpMask, DL, MVT::i32));
2538   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2539   // add the f16 bias (15) to get the biased exponent for the f16 format.
2540   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2541                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2542 
2543   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2544                           DAG.getConstant(8, DL, MVT::i32));
2545   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2546                   DAG.getConstant(0xffe, DL, MVT::i32));
2547 
2548   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2549                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2550   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2551 
2552   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2553   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2554 
2555   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2556   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2557       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2558                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2559 
2560   // N = M | (E << 12);
2561   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2562       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2563                   DAG.getConstant(12, DL, MVT::i32)));
2564 
2565   // B = clamp(1-E, 0, 13);
2566   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2567                                   One, E);
2568   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2569   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2570                   DAG.getConstant(13, DL, MVT::i32));
2571 
2572   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2573                                    DAG.getConstant(0x1000, DL, MVT::i32));
2574 
2575   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2576   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2577   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2578   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2579 
2580   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2581   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2582                               DAG.getConstant(0x7, DL, MVT::i32));
2583   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2584                   DAG.getConstant(2, DL, MVT::i32));
2585   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2586                                One, Zero, ISD::SETEQ);
2587   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2588                                One, Zero, ISD::SETGT);
2589   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2590   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2591 
2592   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2593                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2594   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2595                       I, V, ISD::SETEQ);
2596 
2597   // Extract the sign bit.
2598   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2599                             DAG.getConstant(16, DL, MVT::i32));
2600   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2601                      DAG.getConstant(0x8000, DL, MVT::i32));
2602 
2603   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2604   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2605 }
2606 
2607 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2608                                               SelectionDAG &DAG) const {
2609   SDValue Src = Op.getOperand(0);
2610 
2611   // TODO: Factor out code common with LowerFP_TO_UINT.
2612 
2613   EVT SrcVT = Src.getValueType();
2614   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2615     SDLoc DL(Op);
2616 
2617     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2618     SDValue FpToInt32 =
2619         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2620 
2621     return FpToInt32;
2622   }
2623 
2624   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2625     return LowerFP64_TO_INT(Op, DAG, true);
2626 
2627   return SDValue();
2628 }
2629 
2630 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2631                                               SelectionDAG &DAG) const {
2632   SDValue Src = Op.getOperand(0);
2633 
2634   // TODO: Factor out code common with LowerFP_TO_SINT.
2635 
2636   EVT SrcVT = Src.getValueType();
2637   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2638     SDLoc DL(Op);
2639 
2640     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2641     SDValue FpToInt32 =
2642         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2643 
2644     return FpToInt32;
2645   }
2646 
2647   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2648     return LowerFP64_TO_INT(Op, DAG, false);
2649 
2650   return SDValue();
2651 }
2652 
2653 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2654                                                      SelectionDAG &DAG) const {
2655   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2656   MVT VT = Op.getSimpleValueType();
2657   MVT ScalarVT = VT.getScalarType();
2658 
2659   assert(VT.isVector());
2660 
2661   SDValue Src = Op.getOperand(0);
2662   SDLoc DL(Op);
2663 
2664   // TODO: Don't scalarize on Evergreen?
2665   unsigned NElts = VT.getVectorNumElements();
2666   SmallVector<SDValue, 8> Args;
2667   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2668 
2669   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2670   for (unsigned I = 0; I < NElts; ++I)
2671     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2672 
2673   return DAG.getBuildVector(VT, DL, Args);
2674 }
2675 
2676 //===----------------------------------------------------------------------===//
2677 // Custom DAG optimizations
2678 //===----------------------------------------------------------------------===//
2679 
2680 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2681   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2682 }
2683 
2684 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2685   EVT VT = Op.getValueType();
2686   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2687                                      // as unsigned 24-bit values.
2688     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2689 }
2690 
2691 static bool simplifyI24(SDNode *Node24, unsigned OpIdx,
2692                         TargetLowering::DAGCombinerInfo &DCI) {
2693 
2694   SelectionDAG &DAG = DCI.DAG;
2695   SDValue Op = Node24->getOperand(OpIdx);
2696   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2697   EVT VT = Op.getValueType();
2698 
2699   APInt Demanded = APInt::getLowBitsSet(VT.getSizeInBits(), 24);
2700   APInt KnownZero, KnownOne;
2701   TargetLowering::TargetLoweringOpt TLO(DAG, true, true);
2702   if (TLI.SimplifyDemandedBits(Node24, OpIdx, Demanded, DCI, TLO))
2703     return true;
2704 
2705   return false;
2706 }
2707 
2708 template <typename IntTy>
2709 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2710                                uint32_t Width, const SDLoc &DL) {
2711   if (Width + Offset < 32) {
2712     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2713     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2714     return DAG.getConstant(Result, DL, MVT::i32);
2715   }
2716 
2717   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2718 }
2719 
2720 static bool hasVolatileUser(SDNode *Val) {
2721   for (SDNode *U : Val->uses()) {
2722     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2723       if (M->isVolatile())
2724         return true;
2725     }
2726   }
2727 
2728   return false;
2729 }
2730 
2731 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2732   // i32 vectors are the canonical memory type.
2733   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2734     return false;
2735 
2736   if (!VT.isByteSized())
2737     return false;
2738 
2739   unsigned Size = VT.getStoreSize();
2740 
2741   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2742     return false;
2743 
2744   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2745     return false;
2746 
2747   return true;
2748 }
2749 
2750 // Replace load of an illegal type with a store of a bitcast to a friendlier
2751 // type.
2752 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2753                                                  DAGCombinerInfo &DCI) const {
2754   if (!DCI.isBeforeLegalize())
2755     return SDValue();
2756 
2757   LoadSDNode *LN = cast<LoadSDNode>(N);
2758   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2759     return SDValue();
2760 
2761   SDLoc SL(N);
2762   SelectionDAG &DAG = DCI.DAG;
2763   EVT VT = LN->getMemoryVT();
2764 
2765   unsigned Size = VT.getStoreSize();
2766   unsigned Align = LN->getAlignment();
2767   if (Align < Size && isTypeLegal(VT)) {
2768     bool IsFast;
2769     unsigned AS = LN->getAddressSpace();
2770 
2771     // Expand unaligned loads earlier than legalization. Due to visitation order
2772     // problems during legalization, the emitted instructions to pack and unpack
2773     // the bytes again are not eliminated in the case of an unaligned copy.
2774     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2775       if (VT.isVector())
2776         return scalarizeVectorLoad(LN, DAG);
2777 
2778       SDValue Ops[2];
2779       std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2780       return DAG.getMergeValues(Ops, SDLoc(N));
2781     }
2782 
2783     if (!IsFast)
2784       return SDValue();
2785   }
2786 
2787   if (!shouldCombineMemoryType(VT))
2788     return SDValue();
2789 
2790   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2791 
2792   SDValue NewLoad
2793     = DAG.getLoad(NewVT, SL, LN->getChain(),
2794                   LN->getBasePtr(), LN->getMemOperand());
2795 
2796   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2797   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2798   return SDValue(N, 0);
2799 }
2800 
2801 // Replace store of an illegal type with a store of a bitcast to a friendlier
2802 // type.
2803 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2804                                                   DAGCombinerInfo &DCI) const {
2805   if (!DCI.isBeforeLegalize())
2806     return SDValue();
2807 
2808   StoreSDNode *SN = cast<StoreSDNode>(N);
2809   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2810     return SDValue();
2811 
2812   EVT VT = SN->getMemoryVT();
2813   unsigned Size = VT.getStoreSize();
2814 
2815   SDLoc SL(N);
2816   SelectionDAG &DAG = DCI.DAG;
2817   unsigned Align = SN->getAlignment();
2818   if (Align < Size && isTypeLegal(VT)) {
2819     bool IsFast;
2820     unsigned AS = SN->getAddressSpace();
2821 
2822     // Expand unaligned stores earlier than legalization. Due to visitation
2823     // order problems during legalization, the emitted instructions to pack and
2824     // unpack the bytes again are not eliminated in the case of an unaligned
2825     // copy.
2826     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2827       if (VT.isVector())
2828         return scalarizeVectorStore(SN, DAG);
2829 
2830       return expandUnalignedStore(SN, DAG);
2831     }
2832 
2833     if (!IsFast)
2834       return SDValue();
2835   }
2836 
2837   if (!shouldCombineMemoryType(VT))
2838     return SDValue();
2839 
2840   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2841   SDValue Val = SN->getValue();
2842 
2843   //DCI.AddToWorklist(Val.getNode());
2844 
2845   bool OtherUses = !Val.hasOneUse();
2846   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2847   if (OtherUses) {
2848     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2849     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2850   }
2851 
2852   return DAG.getStore(SN->getChain(), SL, CastVal,
2853                       SN->getBasePtr(), SN->getMemOperand());
2854 }
2855 
2856 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2857 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2858 // issues.
2859 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2860                                                         DAGCombinerInfo &DCI) const {
2861   SelectionDAG &DAG = DCI.DAG;
2862   SDValue N0 = N->getOperand(0);
2863 
2864   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2865   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2866   if (N0.getOpcode() == ISD::TRUNCATE) {
2867     SDValue N1 = N->getOperand(1);
2868     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2869     SDLoc SL(N);
2870 
2871     SDValue Src = N0.getOperand(0);
2872     EVT SrcVT = Src.getValueType();
2873     if (SrcVT.bitsGE(ExtVT)) {
2874       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2875       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2876     }
2877   }
2878 
2879   return SDValue();
2880 }
2881 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
2882 /// binary operation \p Opc to it with the corresponding constant operands.
2883 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
2884   DAGCombinerInfo &DCI, const SDLoc &SL,
2885   unsigned Opc, SDValue LHS,
2886   uint32_t ValLo, uint32_t ValHi) const {
2887   SelectionDAG &DAG = DCI.DAG;
2888   SDValue Lo, Hi;
2889   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
2890 
2891   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
2892   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
2893 
2894   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
2895   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
2896 
2897   // Re-visit the ands. It's possible we eliminated one of them and it could
2898   // simplify the vector.
2899   DCI.AddToWorklist(Lo.getNode());
2900   DCI.AddToWorklist(Hi.getNode());
2901 
2902   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
2903   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2904 }
2905 
2906 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
2907                                                 DAGCombinerInfo &DCI) const {
2908   EVT VT = N->getValueType(0);
2909 
2910   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2911   if (!RHS)
2912     return SDValue();
2913 
2914   SDValue LHS = N->getOperand(0);
2915   unsigned RHSVal = RHS->getZExtValue();
2916   if (!RHSVal)
2917     return LHS;
2918 
2919   SDLoc SL(N);
2920   SelectionDAG &DAG = DCI.DAG;
2921 
2922   switch (LHS->getOpcode()) {
2923   default:
2924     break;
2925   case ISD::ZERO_EXTEND:
2926   case ISD::SIGN_EXTEND:
2927   case ISD::ANY_EXTEND: {
2928     SDValue X = LHS->getOperand(0);
2929 
2930     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
2931         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
2932       // Prefer build_vector as the canonical form if packed types are legal.
2933       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
2934       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
2935        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
2936       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
2937     }
2938 
2939     // shl (ext x) => zext (shl x), if shift does not overflow int
2940     if (VT != MVT::i64)
2941       break;
2942     KnownBits Known;
2943     DAG.computeKnownBits(X, Known);
2944     unsigned LZ = Known.countMinLeadingZeros();
2945     if (LZ < RHSVal)
2946       break;
2947     EVT XVT = X.getValueType();
2948     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
2949     return DAG.getZExtOrTrunc(Shl, SL, VT);
2950   }
2951   }
2952 
2953   if (VT != MVT::i64)
2954     return SDValue();
2955 
2956   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
2957 
2958   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
2959   // common case, splitting this into a move and a 32-bit shift is faster and
2960   // the same code size.
2961   if (RHSVal < 32)
2962     return SDValue();
2963 
2964   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
2965 
2966   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
2967   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
2968 
2969   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2970 
2971   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
2972   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2973 }
2974 
2975 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
2976                                                 DAGCombinerInfo &DCI) const {
2977   if (N->getValueType(0) != MVT::i64)
2978     return SDValue();
2979 
2980   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2981   if (!RHS)
2982     return SDValue();
2983 
2984   SelectionDAG &DAG = DCI.DAG;
2985   SDLoc SL(N);
2986   unsigned RHSVal = RHS->getZExtValue();
2987 
2988   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
2989   if (RHSVal == 32) {
2990     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
2991     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
2992                                    DAG.getConstant(31, SL, MVT::i32));
2993 
2994     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
2995     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
2996   }
2997 
2998   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
2999   if (RHSVal == 63) {
3000     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3001     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3002                                    DAG.getConstant(31, SL, MVT::i32));
3003     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3004     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3005   }
3006 
3007   return SDValue();
3008 }
3009 
3010 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3011                                                 DAGCombinerInfo &DCI) const {
3012   if (N->getValueType(0) != MVT::i64)
3013     return SDValue();
3014 
3015   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3016   if (!RHS)
3017     return SDValue();
3018 
3019   unsigned ShiftAmt = RHS->getZExtValue();
3020   if (ShiftAmt < 32)
3021     return SDValue();
3022 
3023   // srl i64:x, C for C >= 32
3024   // =>
3025   //   build_pair (srl hi_32(x), C - 32), 0
3026 
3027   SelectionDAG &DAG = DCI.DAG;
3028   SDLoc SL(N);
3029 
3030   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3031   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3032 
3033   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, N->getOperand(0));
3034   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32,
3035                            VecOp, One);
3036 
3037   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3038   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3039 
3040   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3041 
3042   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3043 }
3044 
3045 SDValue AMDGPUTargetLowering::performTruncateCombine(
3046   SDNode *N, DAGCombinerInfo &DCI) const {
3047   SDLoc SL(N);
3048   SelectionDAG &DAG = DCI.DAG;
3049   EVT VT = N->getValueType(0);
3050   SDValue Src = N->getOperand(0);
3051 
3052   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3053   if (Src.getOpcode() == ISD::BITCAST) {
3054     SDValue Vec = Src.getOperand(0);
3055     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3056       SDValue Elt0 = Vec.getOperand(0);
3057       EVT EltVT = Elt0.getValueType();
3058       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3059         if (EltVT.isFloatingPoint()) {
3060           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3061                              EltVT.changeTypeToInteger(), Elt0);
3062         }
3063 
3064         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3065       }
3066     }
3067   }
3068 
3069   // Equivalent of above for accessing the high element of a vector as an
3070   // integer operation.
3071   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3072   if (Src.getOpcode() == ISD::SRL) {
3073     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3074       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3075         SDValue BV = stripBitcast(Src.getOperand(0));
3076         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3077             BV.getValueType().getVectorNumElements() == 2) {
3078           SDValue SrcElt = BV.getOperand(1);
3079           EVT SrcEltVT = SrcElt.getValueType();
3080           if (SrcEltVT.isFloatingPoint()) {
3081             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3082                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3083           }
3084 
3085           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3086         }
3087       }
3088     }
3089   }
3090 
3091   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3092   //
3093   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3094   //     i16 (trunc (srl (i32 (trunc x), K)))
3095   if (VT.getScalarSizeInBits() < 32) {
3096     EVT SrcVT = Src.getValueType();
3097     if (SrcVT.getScalarSizeInBits() > 32 &&
3098         (Src.getOpcode() == ISD::SRL ||
3099          Src.getOpcode() == ISD::SRA ||
3100          Src.getOpcode() == ISD::SHL)) {
3101       SDValue Amt = Src.getOperand(1);
3102       KnownBits Known;
3103       DAG.computeKnownBits(Amt, Known);
3104       unsigned Size = VT.getScalarSizeInBits();
3105       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3106           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3107         EVT MidVT = VT.isVector() ?
3108           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3109                            VT.getVectorNumElements()) : MVT::i32;
3110 
3111         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3112         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3113                                     Src.getOperand(0));
3114         DCI.AddToWorklist(Trunc.getNode());
3115 
3116         if (Amt.getValueType() != NewShiftVT) {
3117           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3118           DCI.AddToWorklist(Amt.getNode());
3119         }
3120 
3121         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3122                                           Trunc, Amt);
3123         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3124       }
3125     }
3126   }
3127 
3128   return SDValue();
3129 }
3130 
3131 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3132 // instructions. If we only match on the legalized i64 mul expansion,
3133 // SimplifyDemandedBits will be unable to remove them because there will be
3134 // multiple uses due to the separate mul + mulh[su].
3135 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3136                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3137   if (Size <= 32) {
3138     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3139     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3140   }
3141 
3142   // Because we want to eliminate extension instructions before the
3143   // operation, we need to create a single user here (i.e. not the separate
3144   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3145 
3146   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3147 
3148   SDValue Mul = DAG.getNode(MulOpc, SL,
3149                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3150 
3151   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3152                      Mul.getValue(0), Mul.getValue(1));
3153 }
3154 
3155 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3156                                                 DAGCombinerInfo &DCI) const {
3157   EVT VT = N->getValueType(0);
3158 
3159   unsigned Size = VT.getSizeInBits();
3160   if (VT.isVector() || Size > 64)
3161     return SDValue();
3162 
3163   // There are i16 integer mul/mad.
3164   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3165     return SDValue();
3166 
3167   SelectionDAG &DAG = DCI.DAG;
3168   SDLoc DL(N);
3169 
3170   SDValue N0 = N->getOperand(0);
3171   SDValue N1 = N->getOperand(1);
3172 
3173   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3174   // in the source into any_extends if the result of the mul is truncated. Since
3175   // we can assume the high bits are whatever we want, use the underlying value
3176   // to avoid the unknown high bits from interfering.
3177   if (N0.getOpcode() == ISD::ANY_EXTEND)
3178     N0 = N0.getOperand(0);
3179 
3180   if (N1.getOpcode() == ISD::ANY_EXTEND)
3181     N1 = N1.getOperand(0);
3182 
3183   SDValue Mul;
3184 
3185   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3186     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3187     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3188     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3189   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3190     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3191     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3192     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3193   } else {
3194     return SDValue();
3195   }
3196 
3197   // We need to use sext even for MUL_U24, because MUL_U24 is used
3198   // for signed multiply of 8 and 16-bit types.
3199   return DAG.getSExtOrTrunc(Mul, DL, VT);
3200 }
3201 
3202 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3203                                                   DAGCombinerInfo &DCI) const {
3204   EVT VT = N->getValueType(0);
3205 
3206   if (!Subtarget->hasMulI24() || VT.isVector())
3207     return SDValue();
3208 
3209   SelectionDAG &DAG = DCI.DAG;
3210   SDLoc DL(N);
3211 
3212   SDValue N0 = N->getOperand(0);
3213   SDValue N1 = N->getOperand(1);
3214 
3215   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3216     return SDValue();
3217 
3218   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3219   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3220 
3221   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3222   DCI.AddToWorklist(Mulhi.getNode());
3223   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3224 }
3225 
3226 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3227                                                   DAGCombinerInfo &DCI) const {
3228   EVT VT = N->getValueType(0);
3229 
3230   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3231     return SDValue();
3232 
3233   SelectionDAG &DAG = DCI.DAG;
3234   SDLoc DL(N);
3235 
3236   SDValue N0 = N->getOperand(0);
3237   SDValue N1 = N->getOperand(1);
3238 
3239   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3240     return SDValue();
3241 
3242   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3243   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3244 
3245   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3246   DCI.AddToWorklist(Mulhi.getNode());
3247   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3248 }
3249 
3250 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3251   SDNode *N, DAGCombinerInfo &DCI) const {
3252   SelectionDAG &DAG = DCI.DAG;
3253 
3254   // Simplify demanded bits before splitting into multiple users.
3255   if (simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI))
3256     return SDValue();
3257 
3258   SDValue N0 = N->getOperand(0);
3259   SDValue N1 = N->getOperand(1);
3260 
3261   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3262 
3263   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3264   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3265 
3266   SDLoc SL(N);
3267 
3268   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3269   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3270   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3271 }
3272 
3273 static bool isNegativeOne(SDValue Val) {
3274   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3275     return C->isAllOnesValue();
3276   return false;
3277 }
3278 
3279 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3280                                           SDValue Op,
3281                                           const SDLoc &DL,
3282                                           unsigned Opc) const {
3283   EVT VT = Op.getValueType();
3284   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3285   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3286                               LegalVT != MVT::i16))
3287     return SDValue();
3288 
3289   if (VT != MVT::i32)
3290     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3291 
3292   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3293   if (VT != MVT::i32)
3294     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3295 
3296   return FFBX;
3297 }
3298 
3299 // The native instructions return -1 on 0 input. Optimize out a select that
3300 // produces -1 on 0.
3301 //
3302 // TODO: If zero is not undef, we could also do this if the output is compared
3303 // against the bitwidth.
3304 //
3305 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3306 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3307                                                  SDValue LHS, SDValue RHS,
3308                                                  DAGCombinerInfo &DCI) const {
3309   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3310   if (!CmpRhs || !CmpRhs->isNullValue())
3311     return SDValue();
3312 
3313   SelectionDAG &DAG = DCI.DAG;
3314   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3315   SDValue CmpLHS = Cond.getOperand(0);
3316 
3317   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3318                                            AMDGPUISD::FFBH_U32;
3319 
3320   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3321   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3322   if (CCOpcode == ISD::SETEQ &&
3323       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3324       RHS.getOperand(0) == CmpLHS &&
3325       isNegativeOne(LHS)) {
3326     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3327   }
3328 
3329   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3330   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3331   if (CCOpcode == ISD::SETNE &&
3332       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3333       LHS.getOperand(0) == CmpLHS &&
3334       isNegativeOne(RHS)) {
3335     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3336   }
3337 
3338   return SDValue();
3339 }
3340 
3341 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3342                                          unsigned Op,
3343                                          const SDLoc &SL,
3344                                          SDValue Cond,
3345                                          SDValue N1,
3346                                          SDValue N2) {
3347   SelectionDAG &DAG = DCI.DAG;
3348   EVT VT = N1.getValueType();
3349 
3350   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3351                                   N1.getOperand(0), N2.getOperand(0));
3352   DCI.AddToWorklist(NewSelect.getNode());
3353   return DAG.getNode(Op, SL, VT, NewSelect);
3354 }
3355 
3356 // Pull a free FP operation out of a select so it may fold into uses.
3357 //
3358 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3359 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3360 //
3361 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3362 // select c, (fabs x), +k -> fabs (select c, x, k)
3363 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3364                                     SDValue N) {
3365   SelectionDAG &DAG = DCI.DAG;
3366   SDValue Cond = N.getOperand(0);
3367   SDValue LHS = N.getOperand(1);
3368   SDValue RHS = N.getOperand(2);
3369 
3370   EVT VT = N.getValueType();
3371   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3372       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3373     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3374                                      SDLoc(N), Cond, LHS, RHS);
3375   }
3376 
3377   bool Inv = false;
3378   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3379     std::swap(LHS, RHS);
3380     Inv = true;
3381   }
3382 
3383   // TODO: Support vector constants.
3384   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3385   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3386     SDLoc SL(N);
3387     // If one side is an fneg/fabs and the other is a constant, we can push the
3388     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3389     SDValue NewLHS = LHS.getOperand(0);
3390     SDValue NewRHS = RHS;
3391 
3392     // Careful: if the neg can be folded up, don't try to pull it back down.
3393     bool ShouldFoldNeg = true;
3394 
3395     if (NewLHS.hasOneUse()) {
3396       unsigned Opc = NewLHS.getOpcode();
3397       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3398         ShouldFoldNeg = false;
3399       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3400         ShouldFoldNeg = false;
3401     }
3402 
3403     if (ShouldFoldNeg) {
3404       if (LHS.getOpcode() == ISD::FNEG)
3405         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3406       else if (CRHS->isNegative())
3407         return SDValue();
3408 
3409       if (Inv)
3410         std::swap(NewLHS, NewRHS);
3411 
3412       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3413                                       Cond, NewLHS, NewRHS);
3414       DCI.AddToWorklist(NewSelect.getNode());
3415       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3416     }
3417   }
3418 
3419   return SDValue();
3420 }
3421 
3422 
3423 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3424                                                    DAGCombinerInfo &DCI) const {
3425   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3426     return Folded;
3427 
3428   SDValue Cond = N->getOperand(0);
3429   if (Cond.getOpcode() != ISD::SETCC)
3430     return SDValue();
3431 
3432   EVT VT = N->getValueType(0);
3433   SDValue LHS = Cond.getOperand(0);
3434   SDValue RHS = Cond.getOperand(1);
3435   SDValue CC = Cond.getOperand(2);
3436 
3437   SDValue True = N->getOperand(1);
3438   SDValue False = N->getOperand(2);
3439 
3440   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3441     SelectionDAG &DAG = DCI.DAG;
3442     if ((DAG.isConstantValueOfAnyType(True) ||
3443          DAG.isConstantValueOfAnyType(True)) &&
3444         (!DAG.isConstantValueOfAnyType(False) &&
3445          !DAG.isConstantValueOfAnyType(False))) {
3446       // Swap cmp + select pair to move constant to false input.
3447       // This will allow using VOPC cndmasks more often.
3448       // select (setcc x, y), k, x -> select (setcc y, x) x, x
3449 
3450       SDLoc SL(N);
3451       ISD::CondCode NewCC = getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
3452                                             LHS.getValueType().isInteger());
3453 
3454       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3455       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3456     }
3457 
3458     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3459       SDValue MinMax
3460         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3461       // Revisit this node so we can catch min3/max3/med3 patterns.
3462       //DCI.AddToWorklist(MinMax.getNode());
3463       return MinMax;
3464     }
3465   }
3466 
3467   // There's no reason to not do this if the condition has other uses.
3468   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3469 }
3470 
3471 static bool isConstantFPZero(SDValue N) {
3472   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N))
3473     return C->isZero() && !C->isNegative();
3474   return false;
3475 }
3476 
3477 static unsigned inverseMinMax(unsigned Opc) {
3478   switch (Opc) {
3479   case ISD::FMAXNUM:
3480     return ISD::FMINNUM;
3481   case ISD::FMINNUM:
3482     return ISD::FMAXNUM;
3483   case AMDGPUISD::FMAX_LEGACY:
3484     return AMDGPUISD::FMIN_LEGACY;
3485   case AMDGPUISD::FMIN_LEGACY:
3486     return  AMDGPUISD::FMAX_LEGACY;
3487   default:
3488     llvm_unreachable("invalid min/max opcode");
3489   }
3490 }
3491 
3492 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3493                                                  DAGCombinerInfo &DCI) const {
3494   SelectionDAG &DAG = DCI.DAG;
3495   SDValue N0 = N->getOperand(0);
3496   EVT VT = N->getValueType(0);
3497 
3498   unsigned Opc = N0.getOpcode();
3499 
3500   // If the input has multiple uses and we can either fold the negate down, or
3501   // the other uses cannot, give up. This both prevents unprofitable
3502   // transformations and infinite loops: we won't repeatedly try to fold around
3503   // a negate that has no 'good' form.
3504   if (N0.hasOneUse()) {
3505     // This may be able to fold into the source, but at a code size cost. Don't
3506     // fold if the fold into the user is free.
3507     if (allUsesHaveSourceMods(N, 0))
3508       return SDValue();
3509   } else {
3510     if (fnegFoldsIntoOp(Opc) &&
3511         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3512       return SDValue();
3513   }
3514 
3515   SDLoc SL(N);
3516   switch (Opc) {
3517   case ISD::FADD: {
3518     if (!mayIgnoreSignedZero(N0))
3519       return SDValue();
3520 
3521     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3522     SDValue LHS = N0.getOperand(0);
3523     SDValue RHS = N0.getOperand(1);
3524 
3525     if (LHS.getOpcode() != ISD::FNEG)
3526       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3527     else
3528       LHS = LHS.getOperand(0);
3529 
3530     if (RHS.getOpcode() != ISD::FNEG)
3531       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3532     else
3533       RHS = RHS.getOperand(0);
3534 
3535     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3536     if (!N0.hasOneUse())
3537       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3538     return Res;
3539   }
3540   case ISD::FMUL:
3541   case AMDGPUISD::FMUL_LEGACY: {
3542     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3543     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3544     SDValue LHS = N0.getOperand(0);
3545     SDValue RHS = N0.getOperand(1);
3546 
3547     if (LHS.getOpcode() == ISD::FNEG)
3548       LHS = LHS.getOperand(0);
3549     else if (RHS.getOpcode() == ISD::FNEG)
3550       RHS = RHS.getOperand(0);
3551     else
3552       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3553 
3554     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3555     if (!N0.hasOneUse())
3556       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3557     return Res;
3558   }
3559   case ISD::FMA:
3560   case ISD::FMAD: {
3561     if (!mayIgnoreSignedZero(N0))
3562       return SDValue();
3563 
3564     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3565     SDValue LHS = N0.getOperand(0);
3566     SDValue MHS = N0.getOperand(1);
3567     SDValue RHS = N0.getOperand(2);
3568 
3569     if (LHS.getOpcode() == ISD::FNEG)
3570       LHS = LHS.getOperand(0);
3571     else if (MHS.getOpcode() == ISD::FNEG)
3572       MHS = MHS.getOperand(0);
3573     else
3574       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3575 
3576     if (RHS.getOpcode() != ISD::FNEG)
3577       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3578     else
3579       RHS = RHS.getOperand(0);
3580 
3581     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3582     if (!N0.hasOneUse())
3583       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3584     return Res;
3585   }
3586   case ISD::FMAXNUM:
3587   case ISD::FMINNUM:
3588   case AMDGPUISD::FMAX_LEGACY:
3589   case AMDGPUISD::FMIN_LEGACY: {
3590     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3591     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3592     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3593     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3594 
3595     SDValue LHS = N0.getOperand(0);
3596     SDValue RHS = N0.getOperand(1);
3597 
3598     // 0 doesn't have a negated inline immediate.
3599     // TODO: Shouldn't fold 1/2pi either, and should be generalized to other
3600     // operations.
3601     if (isConstantFPZero(RHS))
3602       return SDValue();
3603 
3604     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3605     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3606     unsigned Opposite = inverseMinMax(Opc);
3607 
3608     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3609     if (!N0.hasOneUse())
3610       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3611     return Res;
3612   }
3613   case ISD::FP_EXTEND:
3614   case ISD::FTRUNC:
3615   case ISD::FRINT:
3616   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3617   case ISD::FSIN:
3618   case AMDGPUISD::RCP:
3619   case AMDGPUISD::RCP_LEGACY:
3620   case AMDGPUISD::SIN_HW: {
3621     SDValue CvtSrc = N0.getOperand(0);
3622     if (CvtSrc.getOpcode() == ISD::FNEG) {
3623       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3624       // (fneg (rcp (fneg x))) -> (rcp x)
3625       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3626     }
3627 
3628     if (!N0.hasOneUse())
3629       return SDValue();
3630 
3631     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3632     // (fneg (rcp x)) -> (rcp (fneg x))
3633     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3634     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3635   }
3636   case ISD::FP_ROUND: {
3637     SDValue CvtSrc = N0.getOperand(0);
3638 
3639     if (CvtSrc.getOpcode() == ISD::FNEG) {
3640       // (fneg (fp_round (fneg x))) -> (fp_round x)
3641       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3642                          CvtSrc.getOperand(0), N0.getOperand(1));
3643     }
3644 
3645     if (!N0.hasOneUse())
3646       return SDValue();
3647 
3648     // (fneg (fp_round x)) -> (fp_round (fneg x))
3649     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3650     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3651   }
3652   case ISD::FP16_TO_FP: {
3653     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3654     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3655     // Put the fneg back as a legal source operation that can be matched later.
3656     SDLoc SL(N);
3657 
3658     SDValue Src = N0.getOperand(0);
3659     EVT SrcVT = Src.getValueType();
3660 
3661     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3662     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3663                                   DAG.getConstant(0x8000, SL, SrcVT));
3664     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3665   }
3666   default:
3667     return SDValue();
3668   }
3669 }
3670 
3671 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3672                                                  DAGCombinerInfo &DCI) const {
3673   SelectionDAG &DAG = DCI.DAG;
3674   SDValue N0 = N->getOperand(0);
3675 
3676   if (!N0.hasOneUse())
3677     return SDValue();
3678 
3679   switch (N0.getOpcode()) {
3680   case ISD::FP16_TO_FP: {
3681     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3682     SDLoc SL(N);
3683     SDValue Src = N0.getOperand(0);
3684     EVT SrcVT = Src.getValueType();
3685 
3686     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3687     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3688                                   DAG.getConstant(0x7fff, SL, SrcVT));
3689     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3690   }
3691   default:
3692     return SDValue();
3693   }
3694 }
3695 
3696 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3697                                                 DAGCombinerInfo &DCI) const {
3698   SelectionDAG &DAG = DCI.DAG;
3699   SDLoc DL(N);
3700 
3701   switch(N->getOpcode()) {
3702   default:
3703     break;
3704   case ISD::BITCAST: {
3705     EVT DestVT = N->getValueType(0);
3706 
3707     // Push casts through vector builds. This helps avoid emitting a large
3708     // number of copies when materializing floating point vector constants.
3709     //
3710     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3711     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3712     if (DestVT.isVector()) {
3713       SDValue Src = N->getOperand(0);
3714       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3715         EVT SrcVT = Src.getValueType();
3716         unsigned NElts = DestVT.getVectorNumElements();
3717 
3718         if (SrcVT.getVectorNumElements() == NElts) {
3719           EVT DestEltVT = DestVT.getVectorElementType();
3720 
3721           SmallVector<SDValue, 8> CastedElts;
3722           SDLoc SL(N);
3723           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3724             SDValue Elt = Src.getOperand(I);
3725             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3726           }
3727 
3728           return DAG.getBuildVector(DestVT, SL, CastedElts);
3729         }
3730       }
3731     }
3732 
3733     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3734       break;
3735 
3736     // Fold bitcasts of constants.
3737     //
3738     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3739     // TODO: Generalize and move to DAGCombiner
3740     SDValue Src = N->getOperand(0);
3741     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3742       if (Src.getValueType() == MVT::i64) {
3743         SDLoc SL(N);
3744         uint64_t CVal = C->getZExtValue();
3745         return DAG.getNode(ISD::BUILD_VECTOR, SL, DestVT,
3746                            DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3747                            DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3748       }
3749     }
3750 
3751     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3752       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3753       SDLoc SL(N);
3754       uint64_t CVal = Val.getZExtValue();
3755       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3756                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3757                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3758 
3759       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3760     }
3761 
3762     break;
3763   }
3764   case ISD::SHL: {
3765     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3766       break;
3767 
3768     return performShlCombine(N, DCI);
3769   }
3770   case ISD::SRL: {
3771     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3772       break;
3773 
3774     return performSrlCombine(N, DCI);
3775   }
3776   case ISD::SRA: {
3777     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3778       break;
3779 
3780     return performSraCombine(N, DCI);
3781   }
3782   case ISD::TRUNCATE:
3783     return performTruncateCombine(N, DCI);
3784   case ISD::MUL:
3785     return performMulCombine(N, DCI);
3786   case ISD::MULHS:
3787     return performMulhsCombine(N, DCI);
3788   case ISD::MULHU:
3789     return performMulhuCombine(N, DCI);
3790   case AMDGPUISD::MUL_I24:
3791   case AMDGPUISD::MUL_U24:
3792   case AMDGPUISD::MULHI_I24:
3793   case AMDGPUISD::MULHI_U24: {
3794     // If the first call to simplify is successfull, then N may end up being
3795     // deleted, so we shouldn't call simplifyI24 again.
3796     simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI);
3797     return SDValue();
3798   }
3799   case AMDGPUISD::MUL_LOHI_I24:
3800   case AMDGPUISD::MUL_LOHI_U24:
3801     return performMulLoHi24Combine(N, DCI);
3802   case ISD::SELECT:
3803     return performSelectCombine(N, DCI);
3804   case ISD::FNEG:
3805     return performFNegCombine(N, DCI);
3806   case ISD::FABS:
3807     return performFAbsCombine(N, DCI);
3808   case AMDGPUISD::BFE_I32:
3809   case AMDGPUISD::BFE_U32: {
3810     assert(!N->getValueType(0).isVector() &&
3811            "Vector handling of BFE not implemented");
3812     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
3813     if (!Width)
3814       break;
3815 
3816     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
3817     if (WidthVal == 0)
3818       return DAG.getConstant(0, DL, MVT::i32);
3819 
3820     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
3821     if (!Offset)
3822       break;
3823 
3824     SDValue BitsFrom = N->getOperand(0);
3825     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
3826 
3827     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
3828 
3829     if (OffsetVal == 0) {
3830       // This is already sign / zero extended, so try to fold away extra BFEs.
3831       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
3832 
3833       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
3834       if (OpSignBits >= SignBits)
3835         return BitsFrom;
3836 
3837       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
3838       if (Signed) {
3839         // This is a sign_extend_inreg. Replace it to take advantage of existing
3840         // DAG Combines. If not eliminated, we will match back to BFE during
3841         // selection.
3842 
3843         // TODO: The sext_inreg of extended types ends, although we can could
3844         // handle them in a single BFE.
3845         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
3846                            DAG.getValueType(SmallVT));
3847       }
3848 
3849       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
3850     }
3851 
3852     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
3853       if (Signed) {
3854         return constantFoldBFE<int32_t>(DAG,
3855                                         CVal->getSExtValue(),
3856                                         OffsetVal,
3857                                         WidthVal,
3858                                         DL);
3859       }
3860 
3861       return constantFoldBFE<uint32_t>(DAG,
3862                                        CVal->getZExtValue(),
3863                                        OffsetVal,
3864                                        WidthVal,
3865                                        DL);
3866     }
3867 
3868     if ((OffsetVal + WidthVal) >= 32 &&
3869         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
3870       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
3871       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
3872                          BitsFrom, ShiftVal);
3873     }
3874 
3875     if (BitsFrom.hasOneUse()) {
3876       APInt Demanded = APInt::getBitsSet(32,
3877                                          OffsetVal,
3878                                          OffsetVal + WidthVal);
3879 
3880       KnownBits Known;
3881       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
3882                                             !DCI.isBeforeLegalizeOps());
3883       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
3884       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
3885           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
3886         DCI.CommitTargetLoweringOpt(TLO);
3887       }
3888     }
3889 
3890     break;
3891   }
3892   case ISD::LOAD:
3893     return performLoadCombine(N, DCI);
3894   case ISD::STORE:
3895     return performStoreCombine(N, DCI);
3896   case AMDGPUISD::RCP: {
3897     if (const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0))) {
3898       // XXX - Should this flush denormals?
3899       const APFloat &Val = CFP->getValueAPF();
3900       APFloat One(Val.getSemantics(), "1.0");
3901       return DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3902     }
3903 
3904     break;
3905   }
3906   case ISD::AssertZext:
3907   case ISD::AssertSext:
3908     return performAssertSZExtCombine(N, DCI);
3909   }
3910   return SDValue();
3911 }
3912 
3913 //===----------------------------------------------------------------------===//
3914 // Helper functions
3915 //===----------------------------------------------------------------------===//
3916 
3917 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
3918                                                    const TargetRegisterClass *RC,
3919                                                    unsigned Reg, EVT VT,
3920                                                    const SDLoc &SL,
3921                                                    bool RawReg) const {
3922   MachineFunction &MF = DAG.getMachineFunction();
3923   MachineRegisterInfo &MRI = MF.getRegInfo();
3924   unsigned VReg;
3925 
3926   if (!MRI.isLiveIn(Reg)) {
3927     VReg = MRI.createVirtualRegister(RC);
3928     MRI.addLiveIn(Reg, VReg);
3929   } else {
3930     VReg = MRI.getLiveInVirtReg(Reg);
3931   }
3932 
3933   if (RawReg)
3934     return DAG.getRegister(VReg, VT);
3935 
3936   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
3937 }
3938 
3939 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
3940                                                   EVT VT,
3941                                                   const SDLoc &SL,
3942                                                   int64_t Offset) const {
3943   MachineFunction &MF = DAG.getMachineFunction();
3944   MachineFrameInfo &MFI = MF.getFrameInfo();
3945 
3946   int FI = MFI.CreateFixedObject(VT.getStoreSize(), Offset, true);
3947   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
3948   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
3949 
3950   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
3951                      MachineMemOperand::MODereferenceable |
3952                      MachineMemOperand::MOInvariant);
3953 }
3954 
3955 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
3956                                                    const SDLoc &SL,
3957                                                    SDValue Chain,
3958                                                    SDValue StackPtr,
3959                                                    SDValue ArgVal,
3960                                                    int64_t Offset) const {
3961   MachineFunction &MF = DAG.getMachineFunction();
3962   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
3963 
3964   SDValue Ptr = DAG.getObjectPtrOffset(SL, StackPtr, Offset);
3965   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
3966                                MachineMemOperand::MODereferenceable);
3967   return Store;
3968 }
3969 
3970 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
3971                                              const TargetRegisterClass *RC,
3972                                              EVT VT, const SDLoc &SL,
3973                                              const ArgDescriptor &Arg) const {
3974   assert(Arg && "Attempting to load missing argument");
3975 
3976   if (Arg.isRegister())
3977     return CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL);
3978   return loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
3979 }
3980 
3981 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
3982     const AMDGPUMachineFunction *MFI, const ImplicitParameter Param) const {
3983   unsigned Alignment = Subtarget->getAlignmentForImplicitArgPtr();
3984   uint64_t ArgOffset = alignTo(MFI->getABIArgOffset(), Alignment);
3985   switch (Param) {
3986   case GRID_DIM:
3987     return ArgOffset;
3988   case GRID_OFFSET:
3989     return ArgOffset + 4;
3990   }
3991   llvm_unreachable("unexpected implicit parameter type");
3992 }
3993 
3994 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
3995 
3996 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
3997   switch ((AMDGPUISD::NodeType)Opcode) {
3998   case AMDGPUISD::FIRST_NUMBER: break;
3999   // AMDIL DAG nodes
4000   NODE_NAME_CASE(UMUL);
4001   NODE_NAME_CASE(BRANCH_COND);
4002 
4003   // AMDGPU DAG nodes
4004   NODE_NAME_CASE(IF)
4005   NODE_NAME_CASE(ELSE)
4006   NODE_NAME_CASE(LOOP)
4007   NODE_NAME_CASE(CALL)
4008   NODE_NAME_CASE(TC_RETURN)
4009   NODE_NAME_CASE(TRAP)
4010   NODE_NAME_CASE(RET_FLAG)
4011   NODE_NAME_CASE(RETURN_TO_EPILOG)
4012   NODE_NAME_CASE(ENDPGM)
4013   NODE_NAME_CASE(DWORDADDR)
4014   NODE_NAME_CASE(FRACT)
4015   NODE_NAME_CASE(SETCC)
4016   NODE_NAME_CASE(SETREG)
4017   NODE_NAME_CASE(FMA_W_CHAIN)
4018   NODE_NAME_CASE(FMUL_W_CHAIN)
4019   NODE_NAME_CASE(CLAMP)
4020   NODE_NAME_CASE(COS_HW)
4021   NODE_NAME_CASE(SIN_HW)
4022   NODE_NAME_CASE(FMAX_LEGACY)
4023   NODE_NAME_CASE(FMIN_LEGACY)
4024   NODE_NAME_CASE(FMAX3)
4025   NODE_NAME_CASE(SMAX3)
4026   NODE_NAME_CASE(UMAX3)
4027   NODE_NAME_CASE(FMIN3)
4028   NODE_NAME_CASE(SMIN3)
4029   NODE_NAME_CASE(UMIN3)
4030   NODE_NAME_CASE(FMED3)
4031   NODE_NAME_CASE(SMED3)
4032   NODE_NAME_CASE(UMED3)
4033   NODE_NAME_CASE(URECIP)
4034   NODE_NAME_CASE(DIV_SCALE)
4035   NODE_NAME_CASE(DIV_FMAS)
4036   NODE_NAME_CASE(DIV_FIXUP)
4037   NODE_NAME_CASE(FMAD_FTZ)
4038   NODE_NAME_CASE(TRIG_PREOP)
4039   NODE_NAME_CASE(RCP)
4040   NODE_NAME_CASE(RSQ)
4041   NODE_NAME_CASE(RCP_LEGACY)
4042   NODE_NAME_CASE(RSQ_LEGACY)
4043   NODE_NAME_CASE(FMUL_LEGACY)
4044   NODE_NAME_CASE(RSQ_CLAMP)
4045   NODE_NAME_CASE(LDEXP)
4046   NODE_NAME_CASE(FP_CLASS)
4047   NODE_NAME_CASE(DOT4)
4048   NODE_NAME_CASE(CARRY)
4049   NODE_NAME_CASE(BORROW)
4050   NODE_NAME_CASE(BFE_U32)
4051   NODE_NAME_CASE(BFE_I32)
4052   NODE_NAME_CASE(BFI)
4053   NODE_NAME_CASE(BFM)
4054   NODE_NAME_CASE(FFBH_U32)
4055   NODE_NAME_CASE(FFBH_I32)
4056   NODE_NAME_CASE(FFBL_B32)
4057   NODE_NAME_CASE(MUL_U24)
4058   NODE_NAME_CASE(MUL_I24)
4059   NODE_NAME_CASE(MULHI_U24)
4060   NODE_NAME_CASE(MULHI_I24)
4061   NODE_NAME_CASE(MUL_LOHI_U24)
4062   NODE_NAME_CASE(MUL_LOHI_I24)
4063   NODE_NAME_CASE(MAD_U24)
4064   NODE_NAME_CASE(MAD_I24)
4065   NODE_NAME_CASE(MAD_I64_I32)
4066   NODE_NAME_CASE(MAD_U64_U32)
4067   NODE_NAME_CASE(PERM)
4068   NODE_NAME_CASE(TEXTURE_FETCH)
4069   NODE_NAME_CASE(EXPORT)
4070   NODE_NAME_CASE(EXPORT_DONE)
4071   NODE_NAME_CASE(R600_EXPORT)
4072   NODE_NAME_CASE(CONST_ADDRESS)
4073   NODE_NAME_CASE(REGISTER_LOAD)
4074   NODE_NAME_CASE(REGISTER_STORE)
4075   NODE_NAME_CASE(SAMPLE)
4076   NODE_NAME_CASE(SAMPLEB)
4077   NODE_NAME_CASE(SAMPLED)
4078   NODE_NAME_CASE(SAMPLEL)
4079   NODE_NAME_CASE(CVT_F32_UBYTE0)
4080   NODE_NAME_CASE(CVT_F32_UBYTE1)
4081   NODE_NAME_CASE(CVT_F32_UBYTE2)
4082   NODE_NAME_CASE(CVT_F32_UBYTE3)
4083   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4084   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4085   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4086   NODE_NAME_CASE(CVT_PK_I16_I32)
4087   NODE_NAME_CASE(CVT_PK_U16_U32)
4088   NODE_NAME_CASE(FP_TO_FP16)
4089   NODE_NAME_CASE(FP16_ZEXT)
4090   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4091   NODE_NAME_CASE(CONST_DATA_PTR)
4092   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4093   NODE_NAME_CASE(KILL)
4094   NODE_NAME_CASE(DUMMY_CHAIN)
4095   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4096   NODE_NAME_CASE(INIT_EXEC)
4097   NODE_NAME_CASE(INIT_EXEC_FROM_INPUT)
4098   NODE_NAME_CASE(SENDMSG)
4099   NODE_NAME_CASE(SENDMSGHALT)
4100   NODE_NAME_CASE(INTERP_MOV)
4101   NODE_NAME_CASE(INTERP_P1)
4102   NODE_NAME_CASE(INTERP_P2)
4103   NODE_NAME_CASE(STORE_MSKOR)
4104   NODE_NAME_CASE(LOAD_CONSTANT)
4105   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4106   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_X3)
4107   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4108   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4109   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4110   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4111   NODE_NAME_CASE(ATOMIC_INC)
4112   NODE_NAME_CASE(ATOMIC_DEC)
4113   NODE_NAME_CASE(ATOMIC_LOAD_FADD)
4114   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4115   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4116   NODE_NAME_CASE(BUFFER_LOAD)
4117   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4118   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4119   NODE_NAME_CASE(BUFFER_STORE)
4120   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4121   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4122   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4123   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4124   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4125   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4126   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4127   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4128   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4129   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4130   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4131   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4132   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4133   NODE_NAME_CASE(IMAGE_LOAD)
4134   NODE_NAME_CASE(IMAGE_LOAD_MIP)
4135   NODE_NAME_CASE(IMAGE_STORE)
4136   NODE_NAME_CASE(IMAGE_STORE_MIP)
4137   // Basic sample.
4138   NODE_NAME_CASE(IMAGE_SAMPLE)
4139   NODE_NAME_CASE(IMAGE_SAMPLE_CL)
4140   NODE_NAME_CASE(IMAGE_SAMPLE_D)
4141   NODE_NAME_CASE(IMAGE_SAMPLE_D_CL)
4142   NODE_NAME_CASE(IMAGE_SAMPLE_L)
4143   NODE_NAME_CASE(IMAGE_SAMPLE_B)
4144   NODE_NAME_CASE(IMAGE_SAMPLE_B_CL)
4145   NODE_NAME_CASE(IMAGE_SAMPLE_LZ)
4146   NODE_NAME_CASE(IMAGE_SAMPLE_CD)
4147   NODE_NAME_CASE(IMAGE_SAMPLE_CD_CL)
4148   // Sample with comparison.
4149   NODE_NAME_CASE(IMAGE_SAMPLE_C)
4150   NODE_NAME_CASE(IMAGE_SAMPLE_C_CL)
4151   NODE_NAME_CASE(IMAGE_SAMPLE_C_D)
4152   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_CL)
4153   NODE_NAME_CASE(IMAGE_SAMPLE_C_L)
4154   NODE_NAME_CASE(IMAGE_SAMPLE_C_B)
4155   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_CL)
4156   NODE_NAME_CASE(IMAGE_SAMPLE_C_LZ)
4157   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD)
4158   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_CL)
4159   // Sample with offsets.
4160   NODE_NAME_CASE(IMAGE_SAMPLE_O)
4161   NODE_NAME_CASE(IMAGE_SAMPLE_CL_O)
4162   NODE_NAME_CASE(IMAGE_SAMPLE_D_O)
4163   NODE_NAME_CASE(IMAGE_SAMPLE_D_CL_O)
4164   NODE_NAME_CASE(IMAGE_SAMPLE_L_O)
4165   NODE_NAME_CASE(IMAGE_SAMPLE_B_O)
4166   NODE_NAME_CASE(IMAGE_SAMPLE_B_CL_O)
4167   NODE_NAME_CASE(IMAGE_SAMPLE_LZ_O)
4168   NODE_NAME_CASE(IMAGE_SAMPLE_CD_O)
4169   NODE_NAME_CASE(IMAGE_SAMPLE_CD_CL_O)
4170   // Sample with comparison and offsets.
4171   NODE_NAME_CASE(IMAGE_SAMPLE_C_O)
4172   NODE_NAME_CASE(IMAGE_SAMPLE_C_CL_O)
4173   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_O)
4174   NODE_NAME_CASE(IMAGE_SAMPLE_C_D_CL_O)
4175   NODE_NAME_CASE(IMAGE_SAMPLE_C_L_O)
4176   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_O)
4177   NODE_NAME_CASE(IMAGE_SAMPLE_C_B_CL_O)
4178   NODE_NAME_CASE(IMAGE_SAMPLE_C_LZ_O)
4179   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_O)
4180   NODE_NAME_CASE(IMAGE_SAMPLE_C_CD_CL_O)
4181   // Basic gather4.
4182   NODE_NAME_CASE(IMAGE_GATHER4)
4183   NODE_NAME_CASE(IMAGE_GATHER4_CL)
4184   NODE_NAME_CASE(IMAGE_GATHER4_L)
4185   NODE_NAME_CASE(IMAGE_GATHER4_B)
4186   NODE_NAME_CASE(IMAGE_GATHER4_B_CL)
4187   NODE_NAME_CASE(IMAGE_GATHER4_LZ)
4188   // Gather4 with comparison.
4189   NODE_NAME_CASE(IMAGE_GATHER4_C)
4190   NODE_NAME_CASE(IMAGE_GATHER4_C_CL)
4191   NODE_NAME_CASE(IMAGE_GATHER4_C_L)
4192   NODE_NAME_CASE(IMAGE_GATHER4_C_B)
4193   NODE_NAME_CASE(IMAGE_GATHER4_C_B_CL)
4194   NODE_NAME_CASE(IMAGE_GATHER4_C_LZ)
4195   // Gather4 with offsets.
4196   NODE_NAME_CASE(IMAGE_GATHER4_O)
4197   NODE_NAME_CASE(IMAGE_GATHER4_CL_O)
4198   NODE_NAME_CASE(IMAGE_GATHER4_L_O)
4199   NODE_NAME_CASE(IMAGE_GATHER4_B_O)
4200   NODE_NAME_CASE(IMAGE_GATHER4_B_CL_O)
4201   NODE_NAME_CASE(IMAGE_GATHER4_LZ_O)
4202   // Gather4 with comparison and offsets.
4203   NODE_NAME_CASE(IMAGE_GATHER4_C_O)
4204   NODE_NAME_CASE(IMAGE_GATHER4_C_CL_O)
4205   NODE_NAME_CASE(IMAGE_GATHER4_C_L_O)
4206   NODE_NAME_CASE(IMAGE_GATHER4_C_B_O)
4207   NODE_NAME_CASE(IMAGE_GATHER4_C_B_CL_O)
4208   NODE_NAME_CASE(IMAGE_GATHER4_C_LZ_O)
4209 
4210   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4211   }
4212   return nullptr;
4213 }
4214 
4215 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4216                                               SelectionDAG &DAG, int Enabled,
4217                                               int &RefinementSteps,
4218                                               bool &UseOneConstNR,
4219                                               bool Reciprocal) const {
4220   EVT VT = Operand.getValueType();
4221 
4222   if (VT == MVT::f32) {
4223     RefinementSteps = 0;
4224     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4225   }
4226 
4227   // TODO: There is also f64 rsq instruction, but the documentation is less
4228   // clear on its precision.
4229 
4230   return SDValue();
4231 }
4232 
4233 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4234                                                SelectionDAG &DAG, int Enabled,
4235                                                int &RefinementSteps) const {
4236   EVT VT = Operand.getValueType();
4237 
4238   if (VT == MVT::f32) {
4239     // Reciprocal, < 1 ulp error.
4240     //
4241     // This reciprocal approximation converges to < 0.5 ulp error with one
4242     // newton rhapson performed with two fused multiple adds (FMAs).
4243 
4244     RefinementSteps = 0;
4245     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4246   }
4247 
4248   // TODO: There is also f64 rcp instruction, but the documentation is less
4249   // clear on its precision.
4250 
4251   return SDValue();
4252 }
4253 
4254 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4255     const SDValue Op, KnownBits &Known,
4256     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4257 
4258   Known.resetAll(); // Don't know anything.
4259 
4260   unsigned Opc = Op.getOpcode();
4261 
4262   switch (Opc) {
4263   default:
4264     break;
4265   case AMDGPUISD::CARRY:
4266   case AMDGPUISD::BORROW: {
4267     Known.Zero = APInt::getHighBitsSet(32, 31);
4268     break;
4269   }
4270 
4271   case AMDGPUISD::BFE_I32:
4272   case AMDGPUISD::BFE_U32: {
4273     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4274     if (!CWidth)
4275       return;
4276 
4277     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4278 
4279     if (Opc == AMDGPUISD::BFE_U32)
4280       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4281 
4282     break;
4283   }
4284   case AMDGPUISD::FP_TO_FP16:
4285   case AMDGPUISD::FP16_ZEXT: {
4286     unsigned BitWidth = Known.getBitWidth();
4287 
4288     // High bits are zero.
4289     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4290     break;
4291   }
4292   case AMDGPUISD::MUL_U24:
4293   case AMDGPUISD::MUL_I24: {
4294     KnownBits LHSKnown, RHSKnown;
4295     DAG.computeKnownBits(Op.getOperand(0), LHSKnown, Depth + 1);
4296     DAG.computeKnownBits(Op.getOperand(1), RHSKnown, Depth + 1);
4297 
4298     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4299                       RHSKnown.countMinTrailingZeros();
4300     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4301 
4302     unsigned LHSValBits = 32 - std::max(LHSKnown.countMinSignBits(), 8u);
4303     unsigned RHSValBits = 32 - std::max(RHSKnown.countMinSignBits(), 8u);
4304     unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4305     if (MaxValBits >= 32)
4306       break;
4307     bool Negative = false;
4308     if (Opc == AMDGPUISD::MUL_I24) {
4309       bool LHSNegative = !!(LHSKnown.One  & (1 << 23));
4310       bool LHSPositive = !!(LHSKnown.Zero & (1 << 23));
4311       bool RHSNegative = !!(RHSKnown.One  & (1 << 23));
4312       bool RHSPositive = !!(RHSKnown.Zero & (1 << 23));
4313       if ((!LHSNegative && !LHSPositive) || (!RHSNegative && !RHSPositive))
4314         break;
4315       Negative = (LHSNegative && RHSPositive) || (LHSPositive && RHSNegative);
4316     }
4317     if (Negative)
4318       Known.One.setHighBits(32 - MaxValBits);
4319     else
4320       Known.Zero.setHighBits(32 - MaxValBits);
4321     break;
4322   }
4323   case AMDGPUISD::PERM: {
4324     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4325     if (!CMask)
4326       return;
4327 
4328     KnownBits LHSKnown, RHSKnown;
4329     DAG.computeKnownBits(Op.getOperand(0), LHSKnown, Depth + 1);
4330     DAG.computeKnownBits(Op.getOperand(1), RHSKnown, Depth + 1);
4331     unsigned Sel = CMask->getZExtValue();
4332 
4333     for (unsigned I = 0; I < 32; I += 8) {
4334       unsigned SelBits = Sel & 0xff;
4335       if (SelBits < 4) {
4336         SelBits *= 8;
4337         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4338         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4339       } else if (SelBits < 7) {
4340         SelBits = (SelBits & 3) * 8;
4341         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4342         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4343       } else if (SelBits == 0x0c) {
4344         Known.Zero |= 0xff << I;
4345       } else if (SelBits > 0x0c) {
4346         Known.One |= 0xff << I;
4347       }
4348       Sel >>= 8;
4349     }
4350     break;
4351   }
4352   case ISD::INTRINSIC_WO_CHAIN: {
4353     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4354     switch (IID) {
4355     case Intrinsic::amdgcn_mbcnt_lo:
4356     case Intrinsic::amdgcn_mbcnt_hi: {
4357       // These return at most the wavefront size - 1.
4358       unsigned Size = Op.getValueType().getSizeInBits();
4359       Known.Zero.setHighBits(Size - Subtarget->getWavefrontSizeLog2());
4360       break;
4361     }
4362     default:
4363       break;
4364     }
4365   }
4366   }
4367 }
4368 
4369 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4370     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4371     unsigned Depth) const {
4372   switch (Op.getOpcode()) {
4373   case AMDGPUISD::BFE_I32: {
4374     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4375     if (!Width)
4376       return 1;
4377 
4378     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4379     if (!isNullConstant(Op.getOperand(1)))
4380       return SignBits;
4381 
4382     // TODO: Could probably figure something out with non-0 offsets.
4383     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4384     return std::max(SignBits, Op0SignBits);
4385   }
4386 
4387   case AMDGPUISD::BFE_U32: {
4388     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4389     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4390   }
4391 
4392   case AMDGPUISD::CARRY:
4393   case AMDGPUISD::BORROW:
4394     return 31;
4395   case AMDGPUISD::FP_TO_FP16:
4396   case AMDGPUISD::FP16_ZEXT:
4397     return 16;
4398   default:
4399     return 1;
4400   }
4401 }
4402