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/Analysis.h"
34 #include "llvm/CodeGen/CallingConvLower.h"
35 #include "llvm/CodeGen/MachineFunction.h"
36 #include "llvm/CodeGen/MachineRegisterInfo.h"
37 #include "llvm/CodeGen/SelectionDAG.h"
38 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
39 #include "llvm/IR/DataLayout.h"
40 #include "llvm/IR/DiagnosticInfo.h"
41 #include "llvm/Support/KnownBits.h"
42 using namespace llvm;
43 
44 static bool allocateCCRegs(unsigned ValNo, MVT ValVT, MVT LocVT,
45                            CCValAssign::LocInfo LocInfo,
46                            ISD::ArgFlagsTy ArgFlags, CCState &State,
47                            const TargetRegisterClass *RC,
48                            unsigned NumRegs) {
49   ArrayRef<MCPhysReg> RegList = makeArrayRef(RC->begin(), NumRegs);
50   unsigned RegResult = State.AllocateReg(RegList);
51   if (RegResult == AMDGPU::NoRegister)
52     return false;
53 
54   State.addLoc(CCValAssign::getReg(ValNo, ValVT, RegResult, LocVT, LocInfo));
55   return true;
56 }
57 
58 static bool allocateSGPRTuple(unsigned ValNo, MVT ValVT, MVT LocVT,
59                               CCValAssign::LocInfo LocInfo,
60                               ISD::ArgFlagsTy ArgFlags, CCState &State) {
61   switch (LocVT.SimpleTy) {
62   case MVT::i64:
63   case MVT::f64:
64   case MVT::v2i32:
65   case MVT::v2f32:
66   case MVT::v4i16:
67   case MVT::v4f16: {
68     // Up to SGPR0-SGPR39
69     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
70                           &AMDGPU::SGPR_64RegClass, 20);
71   }
72   default:
73     return false;
74   }
75 }
76 
77 // Allocate up to VGPR31.
78 //
79 // TODO: Since there are no VGPR alignent requirements would it be better to
80 // split into individual scalar registers?
81 static bool allocateVGPRTuple(unsigned ValNo, MVT ValVT, MVT LocVT,
82                               CCValAssign::LocInfo LocInfo,
83                               ISD::ArgFlagsTy ArgFlags, CCState &State) {
84   switch (LocVT.SimpleTy) {
85   case MVT::i64:
86   case MVT::f64:
87   case MVT::v2i32:
88   case MVT::v2f32:
89   case MVT::v4i16:
90   case MVT::v4f16: {
91     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
92                           &AMDGPU::VReg_64RegClass, 31);
93   }
94   case MVT::v4i32:
95   case MVT::v4f32:
96   case MVT::v2i64:
97   case MVT::v2f64: {
98     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
99                           &AMDGPU::VReg_128RegClass, 29);
100   }
101   case MVT::v8i32:
102   case MVT::v8f32: {
103     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
104                           &AMDGPU::VReg_256RegClass, 25);
105 
106   }
107   case MVT::v16i32:
108   case MVT::v16f32: {
109     return allocateCCRegs(ValNo, ValVT, LocVT, LocInfo, ArgFlags, State,
110                           &AMDGPU::VReg_512RegClass, 17);
111 
112   }
113   default:
114     return false;
115   }
116 }
117 
118 #include "AMDGPUGenCallingConv.inc"
119 
120 // Find a larger type to do a load / store of a vector with.
121 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
122   unsigned StoreSize = VT.getStoreSizeInBits();
123   if (StoreSize <= 32)
124     return EVT::getIntegerVT(Ctx, StoreSize);
125 
126   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
127   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
128 }
129 
130 unsigned AMDGPUTargetLowering::numBitsUnsigned(SDValue Op, SelectionDAG &DAG) {
131   KnownBits Known;
132   EVT VT = Op.getValueType();
133   DAG.computeKnownBits(Op, Known);
134 
135   return VT.getSizeInBits() - Known.countMinLeadingZeros();
136 }
137 
138 unsigned AMDGPUTargetLowering::numBitsSigned(SDValue Op, SelectionDAG &DAG) {
139   EVT VT = Op.getValueType();
140 
141   // In order for this to be a signed 24-bit value, bit 23, must
142   // be a sign bit.
143   return VT.getSizeInBits() - DAG.ComputeNumSignBits(Op);
144 }
145 
146 AMDGPUTargetLowering::AMDGPUTargetLowering(const TargetMachine &TM,
147                                            const AMDGPUSubtarget &STI)
148     : TargetLowering(TM), Subtarget(&STI) {
149   // Lower floating point store/load to integer store/load to reduce the number
150   // of patterns in tablegen.
151   setOperationAction(ISD::LOAD, MVT::f32, Promote);
152   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
153 
154   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
155   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
156 
157   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
158   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
159 
160   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
161   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
162 
163   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
164   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
165 
166   setOperationAction(ISD::LOAD, MVT::i64, Promote);
167   AddPromotedToType(ISD::LOAD, MVT::i64, MVT::v2i32);
168 
169   setOperationAction(ISD::LOAD, MVT::v2i64, Promote);
170   AddPromotedToType(ISD::LOAD, MVT::v2i64, MVT::v4i32);
171 
172   setOperationAction(ISD::LOAD, MVT::f64, Promote);
173   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::v2i32);
174 
175   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
176   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v4i32);
177 
178   // There are no 64-bit extloads. These should be done as a 32-bit extload and
179   // an extension to 64-bit.
180   for (MVT VT : MVT::integer_valuetypes()) {
181     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
182     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
183     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
184   }
185 
186   for (MVT VT : MVT::integer_valuetypes()) {
187     if (VT == MVT::i64)
188       continue;
189 
190     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
191     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Legal);
192     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i16, Legal);
193     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i32, Expand);
194 
195     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
196     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i8, Legal);
197     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Legal);
198     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i32, Expand);
199 
200     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
201     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i8, Legal);
202     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i16, Legal);
203     setLoadExtAction(ISD::EXTLOAD, VT, MVT::i32, Expand);
204   }
205 
206   for (MVT VT : MVT::integer_vector_valuetypes()) {
207     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
208     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
209     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
210     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
211     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
212     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
213     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
214     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
215     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
216     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
217     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
218     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
219   }
220 
221   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
222   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
223   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
224   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
225 
226   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f32, Expand);
227   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f32, Expand);
228   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f32, Expand);
229   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f32, Expand);
230 
231   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
232   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
233   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
234   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
235 
236   setOperationAction(ISD::STORE, MVT::f32, Promote);
237   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
238 
239   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
240   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
241 
242   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
243   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
244 
245   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
246   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
247 
248   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
249   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
250 
251   setOperationAction(ISD::STORE, MVT::i64, Promote);
252   AddPromotedToType(ISD::STORE, MVT::i64, MVT::v2i32);
253 
254   setOperationAction(ISD::STORE, MVT::v2i64, Promote);
255   AddPromotedToType(ISD::STORE, MVT::v2i64, MVT::v4i32);
256 
257   setOperationAction(ISD::STORE, MVT::f64, Promote);
258   AddPromotedToType(ISD::STORE, MVT::f64, MVT::v2i32);
259 
260   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
261   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v4i32);
262 
263   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
264   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
265   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
266   setTruncStoreAction(MVT::i64, MVT::i32, Expand);
267 
268   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
269   setTruncStoreAction(MVT::v2i64, MVT::v2i8, Expand);
270   setTruncStoreAction(MVT::v2i64, MVT::v2i16, Expand);
271   setTruncStoreAction(MVT::v2i64, MVT::v2i32, Expand);
272 
273   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
274   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
275   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
276   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
277 
278   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
279   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
280 
281   setTruncStoreAction(MVT::v2f64, MVT::v2f32, Expand);
282   setTruncStoreAction(MVT::v2f64, MVT::v2f16, Expand);
283 
284   setTruncStoreAction(MVT::v4f64, MVT::v4f32, Expand);
285   setTruncStoreAction(MVT::v4f64, MVT::v4f16, Expand);
286 
287   setTruncStoreAction(MVT::v8f64, MVT::v8f32, Expand);
288   setTruncStoreAction(MVT::v8f64, MVT::v8f16, Expand);
289 
290 
291   setOperationAction(ISD::Constant, MVT::i32, Legal);
292   setOperationAction(ISD::Constant, MVT::i64, Legal);
293   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
294   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
295 
296   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
297   setOperationAction(ISD::BRIND, MVT::Other, Expand);
298 
299   // This is totally unsupported, just custom lower to produce an error.
300   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
301 
302   // Library functions.  These default to Expand, but we have instructions
303   // for them.
304   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
305   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
306   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
307   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
308   setOperationAction(ISD::FABS,   MVT::f32, Legal);
309   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
310   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
311   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
312   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
313   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
314 
315   setOperationAction(ISD::FROUND, MVT::f32, Custom);
316   setOperationAction(ISD::FROUND, MVT::f64, Custom);
317 
318   setOperationAction(ISD::FLOG, MVT::f32, Custom);
319   setOperationAction(ISD::FLOG10, MVT::f32, Custom);
320   setOperationAction(ISD::FEXP, MVT::f32, Custom);
321 
322 
323   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
324   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
325 
326   setOperationAction(ISD::FREM, MVT::f32, Custom);
327   setOperationAction(ISD::FREM, MVT::f64, Custom);
328 
329   // Expand to fneg + fadd.
330   setOperationAction(ISD::FSUB, MVT::f64, Expand);
331 
332   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
333   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
334   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
335   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
336   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
337   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
338   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
339   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
340   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
341   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
342 
343   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
344   setOperationAction(ISD::FP_TO_FP16, MVT::f64, Custom);
345   setOperationAction(ISD::FP_TO_FP16, MVT::f32, Custom);
346 
347   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
348   for (MVT VT : ScalarIntVTs) {
349     // These should use [SU]DIVREM, so set them to expand
350     setOperationAction(ISD::SDIV, VT, Expand);
351     setOperationAction(ISD::UDIV, VT, Expand);
352     setOperationAction(ISD::SREM, VT, Expand);
353     setOperationAction(ISD::UREM, VT, Expand);
354 
355     // GPU does not have divrem function for signed or unsigned.
356     setOperationAction(ISD::SDIVREM, VT, Custom);
357     setOperationAction(ISD::UDIVREM, VT, Custom);
358 
359     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
360     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
361     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
362 
363     setOperationAction(ISD::BSWAP, VT, Expand);
364     setOperationAction(ISD::CTTZ, VT, Expand);
365     setOperationAction(ISD::CTLZ, VT, Expand);
366 
367     // AMDGPU uses ADDC/SUBC/ADDE/SUBE
368     setOperationAction(ISD::ADDC, VT, Legal);
369     setOperationAction(ISD::SUBC, VT, Legal);
370     setOperationAction(ISD::ADDE, VT, Legal);
371     setOperationAction(ISD::SUBE, VT, Legal);
372   }
373 
374   // The hardware supports 32-bit ROTR, but not ROTL.
375   setOperationAction(ISD::ROTL, MVT::i32, Expand);
376   setOperationAction(ISD::ROTL, MVT::i64, Expand);
377   setOperationAction(ISD::ROTR, MVT::i64, Expand);
378 
379   setOperationAction(ISD::MUL, MVT::i64, Expand);
380   setOperationAction(ISD::MULHU, MVT::i64, Expand);
381   setOperationAction(ISD::MULHS, MVT::i64, Expand);
382   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
383   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
384   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
385   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
386   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
387 
388   setOperationAction(ISD::SMIN, MVT::i32, Legal);
389   setOperationAction(ISD::UMIN, MVT::i32, Legal);
390   setOperationAction(ISD::SMAX, MVT::i32, Legal);
391   setOperationAction(ISD::UMAX, MVT::i32, Legal);
392 
393   setOperationAction(ISD::CTTZ, MVT::i64, Custom);
394   setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i64, Custom);
395   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
396   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
397 
398   static const MVT::SimpleValueType VectorIntTypes[] = {
399     MVT::v2i32, MVT::v4i32
400   };
401 
402   for (MVT VT : VectorIntTypes) {
403     // Expand the following operations for the current type by default.
404     setOperationAction(ISD::ADD,  VT, Expand);
405     setOperationAction(ISD::AND,  VT, Expand);
406     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
407     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
408     setOperationAction(ISD::MUL,  VT, Expand);
409     setOperationAction(ISD::MULHU, VT, Expand);
410     setOperationAction(ISD::MULHS, VT, Expand);
411     setOperationAction(ISD::OR,   VT, Expand);
412     setOperationAction(ISD::SHL,  VT, Expand);
413     setOperationAction(ISD::SRA,  VT, Expand);
414     setOperationAction(ISD::SRL,  VT, Expand);
415     setOperationAction(ISD::ROTL, VT, Expand);
416     setOperationAction(ISD::ROTR, VT, Expand);
417     setOperationAction(ISD::SUB,  VT, Expand);
418     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
419     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
420     setOperationAction(ISD::SDIV, VT, Expand);
421     setOperationAction(ISD::UDIV, VT, Expand);
422     setOperationAction(ISD::SREM, VT, Expand);
423     setOperationAction(ISD::UREM, VT, Expand);
424     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
425     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
426     setOperationAction(ISD::SDIVREM, VT, Custom);
427     setOperationAction(ISD::UDIVREM, VT, Expand);
428     setOperationAction(ISD::SELECT, VT, Expand);
429     setOperationAction(ISD::VSELECT, VT, Expand);
430     setOperationAction(ISD::SELECT_CC, VT, Expand);
431     setOperationAction(ISD::XOR,  VT, Expand);
432     setOperationAction(ISD::BSWAP, VT, Expand);
433     setOperationAction(ISD::CTPOP, VT, Expand);
434     setOperationAction(ISD::CTTZ, VT, Expand);
435     setOperationAction(ISD::CTLZ, VT, Expand);
436     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
437     setOperationAction(ISD::SETCC, VT, Expand);
438   }
439 
440   static const MVT::SimpleValueType FloatVectorTypes[] = {
441     MVT::v2f32, MVT::v4f32
442   };
443 
444   for (MVT VT : FloatVectorTypes) {
445     setOperationAction(ISD::FABS, VT, Expand);
446     setOperationAction(ISD::FMINNUM, VT, Expand);
447     setOperationAction(ISD::FMAXNUM, VT, Expand);
448     setOperationAction(ISD::FADD, VT, Expand);
449     setOperationAction(ISD::FCEIL, VT, Expand);
450     setOperationAction(ISD::FCOS, VT, Expand);
451     setOperationAction(ISD::FDIV, VT, Expand);
452     setOperationAction(ISD::FEXP2, VT, Expand);
453     setOperationAction(ISD::FEXP, VT, Expand);
454     setOperationAction(ISD::FLOG2, VT, Expand);
455     setOperationAction(ISD::FREM, VT, Expand);
456     setOperationAction(ISD::FLOG, VT, Expand);
457     setOperationAction(ISD::FLOG10, VT, Expand);
458     setOperationAction(ISD::FPOW, VT, Expand);
459     setOperationAction(ISD::FFLOOR, VT, Expand);
460     setOperationAction(ISD::FTRUNC, VT, Expand);
461     setOperationAction(ISD::FMUL, VT, Expand);
462     setOperationAction(ISD::FMA, VT, Expand);
463     setOperationAction(ISD::FRINT, VT, Expand);
464     setOperationAction(ISD::FNEARBYINT, VT, Expand);
465     setOperationAction(ISD::FSQRT, VT, Expand);
466     setOperationAction(ISD::FSIN, VT, Expand);
467     setOperationAction(ISD::FSUB, VT, Expand);
468     setOperationAction(ISD::FNEG, VT, Expand);
469     setOperationAction(ISD::VSELECT, VT, Expand);
470     setOperationAction(ISD::SELECT_CC, VT, Expand);
471     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
472     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
473     setOperationAction(ISD::SETCC, VT, Expand);
474     setOperationAction(ISD::FCANONICALIZE, VT, Expand);
475   }
476 
477   // This causes using an unrolled select operation rather than expansion with
478   // bit operations. This is in general better, but the alternative using BFI
479   // instructions may be better if the select sources are SGPRs.
480   setOperationAction(ISD::SELECT, MVT::v2f32, Promote);
481   AddPromotedToType(ISD::SELECT, MVT::v2f32, MVT::v2i32);
482 
483   setOperationAction(ISD::SELECT, MVT::v4f32, Promote);
484   AddPromotedToType(ISD::SELECT, MVT::v4f32, MVT::v4i32);
485 
486   // There are no libcalls of any kind.
487   for (int I = 0; I < RTLIB::UNKNOWN_LIBCALL; ++I)
488     setLibcallName(static_cast<RTLIB::Libcall>(I), nullptr);
489 
490   setBooleanContents(ZeroOrNegativeOneBooleanContent);
491   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
492 
493   setSchedulingPreference(Sched::RegPressure);
494   setJumpIsExpensive(true);
495 
496   // FIXME: This is only partially true. If we have to do vector compares, any
497   // SGPR pair can be a condition register. If we have a uniform condition, we
498   // are better off doing SALU operations, where there is only one SCC. For now,
499   // we don't have a way of knowing during instruction selection if a condition
500   // will be uniform and we always use vector compares. Assume we are using
501   // vector compares until that is fixed.
502   setHasMultipleConditionRegisters(true);
503 
504   PredictableSelectIsExpensive = false;
505 
506   // We want to find all load dependencies for long chains of stores to enable
507   // merging into very wide vectors. The problem is with vectors with > 4
508   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
509   // vectors are a legal type, even though we have to split the loads
510   // usually. When we can more precisely specify load legality per address
511   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
512   // smarter so that they can figure out what to do in 2 iterations without all
513   // N > 4 stores on the same chain.
514   GatherAllAliasesMaxDepth = 16;
515 
516   // memcpy/memmove/memset are expanded in the IR, so we shouldn't need to worry
517   // about these during lowering.
518   MaxStoresPerMemcpy  = 0xffffffff;
519   MaxStoresPerMemmove = 0xffffffff;
520   MaxStoresPerMemset  = 0xffffffff;
521 
522   setTargetDAGCombine(ISD::BITCAST);
523   setTargetDAGCombine(ISD::SHL);
524   setTargetDAGCombine(ISD::SRA);
525   setTargetDAGCombine(ISD::SRL);
526   setTargetDAGCombine(ISD::TRUNCATE);
527   setTargetDAGCombine(ISD::MUL);
528   setTargetDAGCombine(ISD::MULHU);
529   setTargetDAGCombine(ISD::MULHS);
530   setTargetDAGCombine(ISD::SELECT);
531   setTargetDAGCombine(ISD::SELECT_CC);
532   setTargetDAGCombine(ISD::STORE);
533   setTargetDAGCombine(ISD::FADD);
534   setTargetDAGCombine(ISD::FSUB);
535   setTargetDAGCombine(ISD::FNEG);
536   setTargetDAGCombine(ISD::FABS);
537   setTargetDAGCombine(ISD::AssertZext);
538   setTargetDAGCombine(ISD::AssertSext);
539 }
540 
541 //===----------------------------------------------------------------------===//
542 // Target Information
543 //===----------------------------------------------------------------------===//
544 
545 LLVM_READNONE
546 static bool fnegFoldsIntoOp(unsigned Opc) {
547   switch (Opc) {
548   case ISD::FADD:
549   case ISD::FSUB:
550   case ISD::FMUL:
551   case ISD::FMA:
552   case ISD::FMAD:
553   case ISD::FMINNUM:
554   case ISD::FMAXNUM:
555   case ISD::FMINNUM_IEEE:
556   case ISD::FMAXNUM_IEEE:
557   case ISD::FSIN:
558   case ISD::FTRUNC:
559   case ISD::FRINT:
560   case ISD::FNEARBYINT:
561   case ISD::FCANONICALIZE:
562   case AMDGPUISD::RCP:
563   case AMDGPUISD::RCP_LEGACY:
564   case AMDGPUISD::RCP_IFLAG:
565   case AMDGPUISD::SIN_HW:
566   case AMDGPUISD::FMUL_LEGACY:
567   case AMDGPUISD::FMIN_LEGACY:
568   case AMDGPUISD::FMAX_LEGACY:
569   case AMDGPUISD::FMED3:
570     return true;
571   default:
572     return false;
573   }
574 }
575 
576 /// \p returns true if the operation will definitely need to use a 64-bit
577 /// encoding, and thus will use a VOP3 encoding regardless of the source
578 /// modifiers.
579 LLVM_READONLY
580 static bool opMustUseVOP3Encoding(const SDNode *N, MVT VT) {
581   return N->getNumOperands() > 2 || VT == MVT::f64;
582 }
583 
584 // Most FP instructions support source modifiers, but this could be refined
585 // slightly.
586 LLVM_READONLY
587 static bool hasSourceMods(const SDNode *N) {
588   if (isa<MemSDNode>(N))
589     return false;
590 
591   switch (N->getOpcode()) {
592   case ISD::CopyToReg:
593   case ISD::SELECT:
594   case ISD::FDIV:
595   case ISD::FREM:
596   case ISD::INLINEASM:
597   case AMDGPUISD::INTERP_P1:
598   case AMDGPUISD::INTERP_P2:
599   case AMDGPUISD::DIV_SCALE:
600 
601   // TODO: Should really be looking at the users of the bitcast. These are
602   // problematic because bitcasts are used to legalize all stores to integer
603   // types.
604   case ISD::BITCAST:
605     return false;
606   default:
607     return true;
608   }
609 }
610 
611 bool AMDGPUTargetLowering::allUsesHaveSourceMods(const SDNode *N,
612                                                  unsigned CostThreshold) {
613   // Some users (such as 3-operand FMA/MAD) must use a VOP3 encoding, and thus
614   // it is truly free to use a source modifier in all cases. If there are
615   // multiple users but for each one will necessitate using VOP3, there will be
616   // a code size increase. Try to avoid increasing code size unless we know it
617   // will save on the instruction count.
618   unsigned NumMayIncreaseSize = 0;
619   MVT VT = N->getValueType(0).getScalarType().getSimpleVT();
620 
621   // XXX - Should this limit number of uses to check?
622   for (const SDNode *U : N->uses()) {
623     if (!hasSourceMods(U))
624       return false;
625 
626     if (!opMustUseVOP3Encoding(U, VT)) {
627       if (++NumMayIncreaseSize > CostThreshold)
628         return false;
629     }
630   }
631 
632   return true;
633 }
634 
635 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
636   return MVT::i32;
637 }
638 
639 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
640   return true;
641 }
642 
643 // The backend supports 32 and 64 bit floating point immediates.
644 // FIXME: Why are we reporting vectors of FP immediates as legal?
645 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
646   EVT ScalarVT = VT.getScalarType();
647   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64 ||
648          (ScalarVT == MVT::f16 && Subtarget->has16BitInsts()));
649 }
650 
651 // We don't want to shrink f64 / f32 constants.
652 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
653   EVT ScalarVT = VT.getScalarType();
654   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
655 }
656 
657 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
658                                                  ISD::LoadExtType,
659                                                  EVT NewVT) const {
660 
661   unsigned NewSize = NewVT.getStoreSizeInBits();
662 
663   // If we are reducing to a 32-bit load, this is always better.
664   if (NewSize == 32)
665     return true;
666 
667   EVT OldVT = N->getValueType(0);
668   unsigned OldSize = OldVT.getStoreSizeInBits();
669 
670   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
671   // extloads, so doing one requires using a buffer_load. In cases where we
672   // still couldn't use a scalar load, using the wider load shouldn't really
673   // hurt anything.
674 
675   // If the old size already had to be an extload, there's no harm in continuing
676   // to reduce the width.
677   return (OldSize < 32);
678 }
679 
680 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy,
681                                                    EVT CastTy) const {
682 
683   assert(LoadTy.getSizeInBits() == CastTy.getSizeInBits());
684 
685   if (LoadTy.getScalarType() == MVT::i32)
686     return false;
687 
688   unsigned LScalarSize = LoadTy.getScalarSizeInBits();
689   unsigned CastScalarSize = CastTy.getScalarSizeInBits();
690 
691   return (LScalarSize < CastScalarSize) ||
692          (CastScalarSize >= 32);
693 }
694 
695 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
696 // profitable with the expansion for 64-bit since it's generally good to
697 // speculate things.
698 // FIXME: These should really have the size as a parameter.
699 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
700   return true;
701 }
702 
703 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
704   return true;
705 }
706 
707 bool AMDGPUTargetLowering::isSDNodeAlwaysUniform(const SDNode * N) const {
708   switch (N->getOpcode()) {
709     default:
710     return false;
711     case ISD::EntryToken:
712     case ISD::TokenFactor:
713       return true;
714     case ISD::INTRINSIC_WO_CHAIN:
715     {
716       unsigned IntrID = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
717       switch (IntrID) {
718         default:
719         return false;
720         case Intrinsic::amdgcn_readfirstlane:
721         case Intrinsic::amdgcn_readlane:
722           return true;
723       }
724     }
725     break;
726     case ISD::LOAD:
727     {
728       const LoadSDNode * L = dyn_cast<LoadSDNode>(N);
729       if (L->getMemOperand()->getAddrSpace()
730       == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
731         return true;
732       return false;
733     }
734     break;
735   }
736 }
737 
738 //===---------------------------------------------------------------------===//
739 // Target Properties
740 //===---------------------------------------------------------------------===//
741 
742 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
743   assert(VT.isFloatingPoint());
744 
745   // Packed operations do not have a fabs modifier.
746   return VT == MVT::f32 || VT == MVT::f64 ||
747          (Subtarget->has16BitInsts() && VT == MVT::f16);
748 }
749 
750 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
751   assert(VT.isFloatingPoint());
752   return VT == MVT::f32 || VT == MVT::f64 ||
753          (Subtarget->has16BitInsts() && VT == MVT::f16) ||
754          (Subtarget->hasVOP3PInsts() && VT == MVT::v2f16);
755 }
756 
757 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
758                                                          unsigned NumElem,
759                                                          unsigned AS) const {
760   return true;
761 }
762 
763 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
764   // There are few operations which truly have vector input operands. Any vector
765   // operation is going to involve operations on each component, and a
766   // build_vector will be a copy per element, so it always makes sense to use a
767   // build_vector input in place of the extracted element to avoid a copy into a
768   // super register.
769   //
770   // We should probably only do this if all users are extracts only, but this
771   // should be the common case.
772   return true;
773 }
774 
775 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
776   // Truncate is just accessing a subregister.
777 
778   unsigned SrcSize = Source.getSizeInBits();
779   unsigned DestSize = Dest.getSizeInBits();
780 
781   return DestSize < SrcSize && DestSize % 32 == 0 ;
782 }
783 
784 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
785   // Truncate is just accessing a subregister.
786 
787   unsigned SrcSize = Source->getScalarSizeInBits();
788   unsigned DestSize = Dest->getScalarSizeInBits();
789 
790   if (DestSize== 16 && Subtarget->has16BitInsts())
791     return SrcSize >= 32;
792 
793   return DestSize < SrcSize && DestSize % 32 == 0;
794 }
795 
796 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
797   unsigned SrcSize = Src->getScalarSizeInBits();
798   unsigned DestSize = Dest->getScalarSizeInBits();
799 
800   if (SrcSize == 16 && Subtarget->has16BitInsts())
801     return DestSize >= 32;
802 
803   return SrcSize == 32 && DestSize == 64;
804 }
805 
806 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
807   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
808   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
809   // this will enable reducing 64-bit operations the 32-bit, which is always
810   // good.
811 
812   if (Src == MVT::i16)
813     return Dest == MVT::i32 ||Dest == MVT::i64 ;
814 
815   return Src == MVT::i32 && Dest == MVT::i64;
816 }
817 
818 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
819   return isZExtFree(Val.getValueType(), VT2);
820 }
821 
822 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
823   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
824   // limited number of native 64-bit operations. Shrinking an operation to fit
825   // in a single 32-bit register should always be helpful. As currently used,
826   // this is much less general than the name suggests, and is only used in
827   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
828   // not profitable, and may actually be harmful.
829   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
830 }
831 
832 //===---------------------------------------------------------------------===//
833 // TargetLowering Callbacks
834 //===---------------------------------------------------------------------===//
835 
836 CCAssignFn *AMDGPUCallLowering::CCAssignFnForCall(CallingConv::ID CC,
837                                                   bool IsVarArg) {
838   switch (CC) {
839   case CallingConv::AMDGPU_KERNEL:
840   case CallingConv::SPIR_KERNEL:
841     llvm_unreachable("kernels should not be handled here");
842   case CallingConv::AMDGPU_VS:
843   case CallingConv::AMDGPU_GS:
844   case CallingConv::AMDGPU_PS:
845   case CallingConv::AMDGPU_CS:
846   case CallingConv::AMDGPU_HS:
847   case CallingConv::AMDGPU_ES:
848   case CallingConv::AMDGPU_LS:
849     return CC_AMDGPU;
850   case CallingConv::C:
851   case CallingConv::Fast:
852   case CallingConv::Cold:
853     return CC_AMDGPU_Func;
854   default:
855     report_fatal_error("Unsupported calling convention.");
856   }
857 }
858 
859 CCAssignFn *AMDGPUCallLowering::CCAssignFnForReturn(CallingConv::ID CC,
860                                                     bool IsVarArg) {
861   switch (CC) {
862   case CallingConv::AMDGPU_KERNEL:
863   case CallingConv::SPIR_KERNEL:
864     llvm_unreachable("kernels should not be handled here");
865   case CallingConv::AMDGPU_VS:
866   case CallingConv::AMDGPU_GS:
867   case CallingConv::AMDGPU_PS:
868   case CallingConv::AMDGPU_CS:
869   case CallingConv::AMDGPU_HS:
870   case CallingConv::AMDGPU_ES:
871   case CallingConv::AMDGPU_LS:
872     return RetCC_SI_Shader;
873   case CallingConv::C:
874   case CallingConv::Fast:
875   case CallingConv::Cold:
876     return RetCC_AMDGPU_Func;
877   default:
878     report_fatal_error("Unsupported calling convention.");
879   }
880 }
881 
882 /// The SelectionDAGBuilder will automatically promote function arguments
883 /// with illegal types.  However, this does not work for the AMDGPU targets
884 /// since the function arguments are stored in memory as these illegal types.
885 /// In order to handle this properly we need to get the original types sizes
886 /// from the LLVM IR Function and fixup the ISD:InputArg values before
887 /// passing them to AnalyzeFormalArguments()
888 
889 /// When the SelectionDAGBuilder computes the Ins, it takes care of splitting
890 /// input values across multiple registers.  Each item in the Ins array
891 /// represents a single value that will be stored in registers.  Ins[x].VT is
892 /// the value type of the value that will be stored in the register, so
893 /// whatever SDNode we lower the argument to needs to be this type.
894 ///
895 /// In order to correctly lower the arguments we need to know the size of each
896 /// argument.  Since Ins[x].VT gives us the size of the register that will
897 /// hold the value, we need to look at Ins[x].ArgVT to see the 'real' type
898 /// for the orignal function argument so that we can deduce the correct memory
899 /// type to use for Ins[x].  In most cases the correct memory type will be
900 /// Ins[x].ArgVT.  However, this will not always be the case.  If, for example,
901 /// we have a kernel argument of type v8i8, this argument will be split into
902 /// 8 parts and each part will be represented by its own item in the Ins array.
903 /// For each part the Ins[x].ArgVT will be the v8i8, which is the full type of
904 /// the argument before it was split.  From this, we deduce that the memory type
905 /// for each individual part is i8.  We pass the memory type as LocVT to the
906 /// calling convention analysis function and the register type (Ins[x].VT) as
907 /// the ValVT.
908 void AMDGPUTargetLowering::analyzeFormalArgumentsCompute(
909   CCState &State,
910   const SmallVectorImpl<ISD::InputArg> &Ins) const {
911   const MachineFunction &MF = State.getMachineFunction();
912   const Function &Fn = MF.getFunction();
913   LLVMContext &Ctx = Fn.getParent()->getContext();
914   const AMDGPUSubtarget &ST = AMDGPUSubtarget::get(MF);
915   const unsigned ExplicitOffset = ST.getExplicitKernelArgOffset(Fn);
916   CallingConv::ID CC = Fn.getCallingConv();
917 
918   unsigned MaxAlign = 1;
919   uint64_t ExplicitArgOffset = 0;
920   const DataLayout &DL = Fn.getParent()->getDataLayout();
921 
922   unsigned InIndex = 0;
923 
924   for (const Argument &Arg : Fn.args()) {
925     Type *BaseArgTy = Arg.getType();
926     unsigned Align = DL.getABITypeAlignment(BaseArgTy);
927     MaxAlign = std::max(Align, MaxAlign);
928     unsigned AllocSize = DL.getTypeAllocSize(BaseArgTy);
929 
930     uint64_t ArgOffset = alignTo(ExplicitArgOffset, Align) + ExplicitOffset;
931     ExplicitArgOffset = alignTo(ExplicitArgOffset, Align) + AllocSize;
932 
933     // We're basically throwing away everything passed into us and starting over
934     // to get accurate in-memory offsets. The "PartOffset" is completely useless
935     // to us as computed in Ins.
936     //
937     // We also need to figure out what type legalization is trying to do to get
938     // the correct memory offsets.
939 
940     SmallVector<EVT, 16> ValueVTs;
941     SmallVector<uint64_t, 16> Offsets;
942     ComputeValueVTs(*this, DL, BaseArgTy, ValueVTs, &Offsets, ArgOffset);
943 
944     for (unsigned Value = 0, NumValues = ValueVTs.size();
945          Value != NumValues; ++Value) {
946       uint64_t BasePartOffset = Offsets[Value];
947 
948       EVT ArgVT = ValueVTs[Value];
949       EVT MemVT = ArgVT;
950       MVT RegisterVT = getRegisterTypeForCallingConv(Ctx, CC, ArgVT);
951       unsigned NumRegs = getNumRegistersForCallingConv(Ctx, CC, ArgVT);
952 
953       if (NumRegs == 1) {
954         // This argument is not split, so the IR type is the memory type.
955         if (ArgVT.isExtended()) {
956           // We have an extended type, like i24, so we should just use the
957           // register type.
958           MemVT = RegisterVT;
959         } else {
960           MemVT = ArgVT;
961         }
962       } else if (ArgVT.isVector() && RegisterVT.isVector() &&
963                  ArgVT.getScalarType() == RegisterVT.getScalarType()) {
964         assert(ArgVT.getVectorNumElements() > RegisterVT.getVectorNumElements());
965         // We have a vector value which has been split into a vector with
966         // the same scalar type, but fewer elements.  This should handle
967         // all the floating-point vector types.
968         MemVT = RegisterVT;
969       } else if (ArgVT.isVector() &&
970                  ArgVT.getVectorNumElements() == NumRegs) {
971         // This arg has been split so that each element is stored in a separate
972         // register.
973         MemVT = ArgVT.getScalarType();
974       } else if (ArgVT.isExtended()) {
975         // We have an extended type, like i65.
976         MemVT = RegisterVT;
977       } else {
978         unsigned MemoryBits = ArgVT.getStoreSizeInBits() / NumRegs;
979         assert(ArgVT.getStoreSizeInBits() % NumRegs == 0);
980         if (RegisterVT.isInteger()) {
981           MemVT = EVT::getIntegerVT(State.getContext(), MemoryBits);
982         } else if (RegisterVT.isVector()) {
983           assert(!RegisterVT.getScalarType().isFloatingPoint());
984           unsigned NumElements = RegisterVT.getVectorNumElements();
985           assert(MemoryBits % NumElements == 0);
986           // This vector type has been split into another vector type with
987           // a different elements size.
988           EVT ScalarVT = EVT::getIntegerVT(State.getContext(),
989                                            MemoryBits / NumElements);
990           MemVT = EVT::getVectorVT(State.getContext(), ScalarVT, NumElements);
991         } else {
992           llvm_unreachable("cannot deduce memory type.");
993         }
994       }
995 
996       // Convert one element vectors to scalar.
997       if (MemVT.isVector() && MemVT.getVectorNumElements() == 1)
998         MemVT = MemVT.getScalarType();
999 
1000       if (MemVT.isExtended()) {
1001         // This should really only happen if we have vec3 arguments
1002         assert(MemVT.isVector() && MemVT.getVectorNumElements() == 3);
1003         MemVT = MemVT.getPow2VectorType(State.getContext());
1004       }
1005 
1006       unsigned PartOffset = 0;
1007       for (unsigned i = 0; i != NumRegs; ++i) {
1008         State.addLoc(CCValAssign::getCustomMem(InIndex++, RegisterVT,
1009                                                BasePartOffset + PartOffset,
1010                                                MemVT.getSimpleVT(),
1011                                                CCValAssign::Full));
1012         PartOffset += MemVT.getStoreSize();
1013       }
1014     }
1015   }
1016 }
1017 
1018 SDValue AMDGPUTargetLowering::LowerReturn(
1019   SDValue Chain, CallingConv::ID CallConv,
1020   bool isVarArg,
1021   const SmallVectorImpl<ISD::OutputArg> &Outs,
1022   const SmallVectorImpl<SDValue> &OutVals,
1023   const SDLoc &DL, SelectionDAG &DAG) const {
1024   // FIXME: Fails for r600 tests
1025   //assert(!isVarArg && Outs.empty() && OutVals.empty() &&
1026   // "wave terminate should not have return values");
1027   return DAG.getNode(AMDGPUISD::ENDPGM, DL, MVT::Other, Chain);
1028 }
1029 
1030 //===---------------------------------------------------------------------===//
1031 // Target specific lowering
1032 //===---------------------------------------------------------------------===//
1033 
1034 /// Selects the correct CCAssignFn for a given CallingConvention value.
1035 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForCall(CallingConv::ID CC,
1036                                                     bool IsVarArg) {
1037   return AMDGPUCallLowering::CCAssignFnForCall(CC, IsVarArg);
1038 }
1039 
1040 CCAssignFn *AMDGPUTargetLowering::CCAssignFnForReturn(CallingConv::ID CC,
1041                                                       bool IsVarArg) {
1042   return AMDGPUCallLowering::CCAssignFnForReturn(CC, IsVarArg);
1043 }
1044 
1045 SDValue AMDGPUTargetLowering::addTokenForArgument(SDValue Chain,
1046                                                   SelectionDAG &DAG,
1047                                                   MachineFrameInfo &MFI,
1048                                                   int ClobberedFI) const {
1049   SmallVector<SDValue, 8> ArgChains;
1050   int64_t FirstByte = MFI.getObjectOffset(ClobberedFI);
1051   int64_t LastByte = FirstByte + MFI.getObjectSize(ClobberedFI) - 1;
1052 
1053   // Include the original chain at the beginning of the list. When this is
1054   // used by target LowerCall hooks, this helps legalize find the
1055   // CALLSEQ_BEGIN node.
1056   ArgChains.push_back(Chain);
1057 
1058   // Add a chain value for each stack argument corresponding
1059   for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
1060                             UE = DAG.getEntryNode().getNode()->use_end();
1061        U != UE; ++U) {
1062     if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U)) {
1063       if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr())) {
1064         if (FI->getIndex() < 0) {
1065           int64_t InFirstByte = MFI.getObjectOffset(FI->getIndex());
1066           int64_t InLastByte = InFirstByte;
1067           InLastByte += MFI.getObjectSize(FI->getIndex()) - 1;
1068 
1069           if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
1070               (FirstByte <= InFirstByte && InFirstByte <= LastByte))
1071             ArgChains.push_back(SDValue(L, 1));
1072         }
1073       }
1074     }
1075   }
1076 
1077   // Build a tokenfactor for all the chains.
1078   return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other, ArgChains);
1079 }
1080 
1081 SDValue AMDGPUTargetLowering::lowerUnhandledCall(CallLoweringInfo &CLI,
1082                                                  SmallVectorImpl<SDValue> &InVals,
1083                                                  StringRef Reason) const {
1084   SDValue Callee = CLI.Callee;
1085   SelectionDAG &DAG = CLI.DAG;
1086 
1087   const Function &Fn = DAG.getMachineFunction().getFunction();
1088 
1089   StringRef FuncName("<unknown>");
1090 
1091   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
1092     FuncName = G->getSymbol();
1093   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
1094     FuncName = G->getGlobal()->getName();
1095 
1096   DiagnosticInfoUnsupported NoCalls(
1097     Fn, Reason + FuncName, CLI.DL.getDebugLoc());
1098   DAG.getContext()->diagnose(NoCalls);
1099 
1100   if (!CLI.IsTailCall) {
1101     for (unsigned I = 0, E = CLI.Ins.size(); I != E; ++I)
1102       InVals.push_back(DAG.getUNDEF(CLI.Ins[I].VT));
1103   }
1104 
1105   return DAG.getEntryNode();
1106 }
1107 
1108 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
1109                                         SmallVectorImpl<SDValue> &InVals) const {
1110   return lowerUnhandledCall(CLI, InVals, "unsupported call to function ");
1111 }
1112 
1113 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
1114                                                       SelectionDAG &DAG) const {
1115   const Function &Fn = DAG.getMachineFunction().getFunction();
1116 
1117   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
1118                                             SDLoc(Op).getDebugLoc());
1119   DAG.getContext()->diagnose(NoDynamicAlloca);
1120   auto Ops = {DAG.getConstant(0, SDLoc(), Op.getValueType()), Op.getOperand(0)};
1121   return DAG.getMergeValues(Ops, SDLoc());
1122 }
1123 
1124 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
1125                                              SelectionDAG &DAG) const {
1126   switch (Op.getOpcode()) {
1127   default:
1128     Op->print(errs(), &DAG);
1129     llvm_unreachable("Custom lowering code for this"
1130                      "instruction is not implemented yet!");
1131     break;
1132   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
1133   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
1134   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
1135   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
1136   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
1137   case ISD::FREM: return LowerFREM(Op, DAG);
1138   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
1139   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
1140   case ISD::FRINT: return LowerFRINT(Op, DAG);
1141   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
1142   case ISD::FROUND: return LowerFROUND(Op, DAG);
1143   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
1144   case ISD::FLOG:
1145     return LowerFLOG(Op, DAG, 1 / AMDGPU_LOG2E_F);
1146   case ISD::FLOG10:
1147     return LowerFLOG(Op, DAG, AMDGPU_LN2_F / AMDGPU_LN10_F);
1148   case ISD::FEXP:
1149     return lowerFEXP(Op, DAG);
1150   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
1151   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
1152   case ISD::FP_TO_FP16: return LowerFP_TO_FP16(Op, DAG);
1153   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
1154   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
1155   case ISD::CTTZ:
1156   case ISD::CTTZ_ZERO_UNDEF:
1157   case ISD::CTLZ:
1158   case ISD::CTLZ_ZERO_UNDEF:
1159     return LowerCTLZ_CTTZ(Op, DAG);
1160   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
1161   }
1162   return Op;
1163 }
1164 
1165 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
1166                                               SmallVectorImpl<SDValue> &Results,
1167                                               SelectionDAG &DAG) const {
1168   switch (N->getOpcode()) {
1169   case ISD::SIGN_EXTEND_INREG:
1170     // Different parts of legalization seem to interpret which type of
1171     // sign_extend_inreg is the one to check for custom lowering. The extended
1172     // from type is what really matters, but some places check for custom
1173     // lowering of the result type. This results in trying to use
1174     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
1175     // nothing here and let the illegal result integer be handled normally.
1176     return;
1177   default:
1178     return;
1179   }
1180 }
1181 
1182 static bool hasDefinedInitializer(const GlobalValue *GV) {
1183   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
1184   if (!GVar || !GVar->hasInitializer())
1185     return false;
1186 
1187   return !isa<UndefValue>(GVar->getInitializer());
1188 }
1189 
1190 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
1191                                                  SDValue Op,
1192                                                  SelectionDAG &DAG) const {
1193 
1194   const DataLayout &DL = DAG.getDataLayout();
1195   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
1196   const GlobalValue *GV = G->getGlobal();
1197 
1198   if (G->getAddressSpace() == AMDGPUAS::LOCAL_ADDRESS ||
1199       G->getAddressSpace() == AMDGPUAS::REGION_ADDRESS) {
1200     if (!MFI->isEntryFunction()) {
1201       const Function &Fn = DAG.getMachineFunction().getFunction();
1202       DiagnosticInfoUnsupported BadLDSDecl(
1203         Fn, "local memory global used by non-kernel function", SDLoc(Op).getDebugLoc());
1204       DAG.getContext()->diagnose(BadLDSDecl);
1205     }
1206 
1207     // XXX: What does the value of G->getOffset() mean?
1208     assert(G->getOffset() == 0 &&
1209          "Do not know what to do with an non-zero offset");
1210 
1211     // TODO: We could emit code to handle the initialization somewhere.
1212     if (!hasDefinedInitializer(GV)) {
1213       unsigned Offset = MFI->allocateLDSGlobal(DL, *GV);
1214       return DAG.getConstant(Offset, SDLoc(Op), Op.getValueType());
1215     }
1216   }
1217 
1218   const Function &Fn = DAG.getMachineFunction().getFunction();
1219   DiagnosticInfoUnsupported BadInit(
1220       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
1221   DAG.getContext()->diagnose(BadInit);
1222   return SDValue();
1223 }
1224 
1225 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
1226                                                   SelectionDAG &DAG) const {
1227   SmallVector<SDValue, 8> Args;
1228 
1229   EVT VT = Op.getValueType();
1230   if (VT == MVT::v4i16 || VT == MVT::v4f16) {
1231     SDLoc SL(Op);
1232     SDValue Lo = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(0));
1233     SDValue Hi = DAG.getNode(ISD::BITCAST, SL, MVT::i32, Op.getOperand(1));
1234 
1235     SDValue BV = DAG.getBuildVector(MVT::v2i32, SL, { Lo, Hi });
1236     return DAG.getNode(ISD::BITCAST, SL, VT, BV);
1237   }
1238 
1239   for (const SDUse &U : Op->ops())
1240     DAG.ExtractVectorElements(U.get(), Args);
1241 
1242   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1243 }
1244 
1245 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
1246                                                      SelectionDAG &DAG) const {
1247 
1248   SmallVector<SDValue, 8> Args;
1249   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
1250   EVT VT = Op.getValueType();
1251   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
1252                             VT.getVectorNumElements());
1253 
1254   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
1255 }
1256 
1257 /// Generate Min/Max node
1258 SDValue AMDGPUTargetLowering::combineFMinMaxLegacy(const SDLoc &DL, EVT VT,
1259                                                    SDValue LHS, SDValue RHS,
1260                                                    SDValue True, SDValue False,
1261                                                    SDValue CC,
1262                                                    DAGCombinerInfo &DCI) const {
1263   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
1264     return SDValue();
1265 
1266   SelectionDAG &DAG = DCI.DAG;
1267   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
1268   switch (CCOpcode) {
1269   case ISD::SETOEQ:
1270   case ISD::SETONE:
1271   case ISD::SETUNE:
1272   case ISD::SETNE:
1273   case ISD::SETUEQ:
1274   case ISD::SETEQ:
1275   case ISD::SETFALSE:
1276   case ISD::SETFALSE2:
1277   case ISD::SETTRUE:
1278   case ISD::SETTRUE2:
1279   case ISD::SETUO:
1280   case ISD::SETO:
1281     break;
1282   case ISD::SETULE:
1283   case ISD::SETULT: {
1284     if (LHS == True)
1285       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1286     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1287   }
1288   case ISD::SETOLE:
1289   case ISD::SETOLT:
1290   case ISD::SETLE:
1291   case ISD::SETLT: {
1292     // Ordered. Assume ordered for undefined.
1293 
1294     // Only do this after legalization to avoid interfering with other combines
1295     // which might occur.
1296     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1297         !DCI.isCalledByLegalizer())
1298       return SDValue();
1299 
1300     // We need to permute the operands to get the correct NaN behavior. The
1301     // selected operand is the second one based on the failing compare with NaN,
1302     // so permute it based on the compare type the hardware uses.
1303     if (LHS == True)
1304       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1305     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1306   }
1307   case ISD::SETUGE:
1308   case ISD::SETUGT: {
1309     if (LHS == True)
1310       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
1311     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
1312   }
1313   case ISD::SETGT:
1314   case ISD::SETGE:
1315   case ISD::SETOGE:
1316   case ISD::SETOGT: {
1317     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
1318         !DCI.isCalledByLegalizer())
1319       return SDValue();
1320 
1321     if (LHS == True)
1322       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
1323     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
1324   }
1325   case ISD::SETCC_INVALID:
1326     llvm_unreachable("Invalid setcc condcode!");
1327   }
1328   return SDValue();
1329 }
1330 
1331 std::pair<SDValue, SDValue>
1332 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
1333   SDLoc SL(Op);
1334 
1335   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1336 
1337   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1338   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1339 
1340   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1341   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1342 
1343   return std::make_pair(Lo, Hi);
1344 }
1345 
1346 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
1347   SDLoc SL(Op);
1348 
1349   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1350   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1351   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1352 }
1353 
1354 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
1355   SDLoc SL(Op);
1356 
1357   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
1358   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1359   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1360 }
1361 
1362 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
1363                                               SelectionDAG &DAG) const {
1364   LoadSDNode *Load = cast<LoadSDNode>(Op);
1365   EVT VT = Op.getValueType();
1366 
1367 
1368   // If this is a 2 element vector, we really want to scalarize and not create
1369   // weird 1 element vectors.
1370   if (VT.getVectorNumElements() == 2)
1371     return scalarizeVectorLoad(Load, DAG);
1372 
1373   SDValue BasePtr = Load->getBasePtr();
1374   EVT MemVT = Load->getMemoryVT();
1375   SDLoc SL(Op);
1376 
1377   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1378 
1379   EVT LoVT, HiVT;
1380   EVT LoMemVT, HiMemVT;
1381   SDValue Lo, Hi;
1382 
1383   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1384   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1385   std::tie(Lo, Hi) = DAG.SplitVector(Op, SL, LoVT, HiVT);
1386 
1387   unsigned Size = LoMemVT.getStoreSize();
1388   unsigned BaseAlign = Load->getAlignment();
1389   unsigned HiAlign = MinAlign(BaseAlign, Size);
1390 
1391   SDValue LoLoad = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1392                                   Load->getChain(), BasePtr, SrcValue, LoMemVT,
1393                                   BaseAlign, Load->getMemOperand()->getFlags());
1394   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, Size);
1395   SDValue HiLoad =
1396       DAG.getExtLoad(Load->getExtensionType(), SL, HiVT, Load->getChain(),
1397                      HiPtr, SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1398                      HiMemVT, HiAlign, Load->getMemOperand()->getFlags());
1399 
1400   SDValue Ops[] = {
1401     DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad),
1402     DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1403                 LoLoad.getValue(1), HiLoad.getValue(1))
1404   };
1405 
1406   return DAG.getMergeValues(Ops, SL);
1407 }
1408 
1409 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1410                                                SelectionDAG &DAG) const {
1411   StoreSDNode *Store = cast<StoreSDNode>(Op);
1412   SDValue Val = Store->getValue();
1413   EVT VT = Val.getValueType();
1414 
1415   // If this is a 2 element vector, we really want to scalarize and not create
1416   // weird 1 element vectors.
1417   if (VT.getVectorNumElements() == 2)
1418     return scalarizeVectorStore(Store, DAG);
1419 
1420   EVT MemVT = Store->getMemoryVT();
1421   SDValue Chain = Store->getChain();
1422   SDValue BasePtr = Store->getBasePtr();
1423   SDLoc SL(Op);
1424 
1425   EVT LoVT, HiVT;
1426   EVT LoMemVT, HiMemVT;
1427   SDValue Lo, Hi;
1428 
1429   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1430   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1431   std::tie(Lo, Hi) = DAG.SplitVector(Val, SL, LoVT, HiVT);
1432 
1433   SDValue HiPtr = DAG.getObjectPtrOffset(SL, BasePtr, LoMemVT.getStoreSize());
1434 
1435   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1436   unsigned BaseAlign = Store->getAlignment();
1437   unsigned Size = LoMemVT.getStoreSize();
1438   unsigned HiAlign = MinAlign(BaseAlign, Size);
1439 
1440   SDValue LoStore =
1441       DAG.getTruncStore(Chain, SL, Lo, BasePtr, SrcValue, LoMemVT, BaseAlign,
1442                         Store->getMemOperand()->getFlags());
1443   SDValue HiStore =
1444       DAG.getTruncStore(Chain, SL, Hi, HiPtr, SrcValue.getWithOffset(Size),
1445                         HiMemVT, HiAlign, Store->getMemOperand()->getFlags());
1446 
1447   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1448 }
1449 
1450 // This is a shortcut for integer division because we have fast i32<->f32
1451 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1452 // float is enough to accurately represent up to a 24-bit signed integer.
1453 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG,
1454                                             bool Sign) const {
1455   SDLoc DL(Op);
1456   EVT VT = Op.getValueType();
1457   SDValue LHS = Op.getOperand(0);
1458   SDValue RHS = Op.getOperand(1);
1459   MVT IntVT = MVT::i32;
1460   MVT FltVT = MVT::f32;
1461 
1462   unsigned LHSSignBits = DAG.ComputeNumSignBits(LHS);
1463   if (LHSSignBits < 9)
1464     return SDValue();
1465 
1466   unsigned RHSSignBits = DAG.ComputeNumSignBits(RHS);
1467   if (RHSSignBits < 9)
1468     return SDValue();
1469 
1470   unsigned BitSize = VT.getSizeInBits();
1471   unsigned SignBits = std::min(LHSSignBits, RHSSignBits);
1472   unsigned DivBits = BitSize - SignBits;
1473   if (Sign)
1474     ++DivBits;
1475 
1476   ISD::NodeType ToFp = Sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1477   ISD::NodeType ToInt = Sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1478 
1479   SDValue jq = DAG.getConstant(1, DL, IntVT);
1480 
1481   if (Sign) {
1482     // char|short jq = ia ^ ib;
1483     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1484 
1485     // jq = jq >> (bitsize - 2)
1486     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1487                      DAG.getConstant(BitSize - 2, DL, VT));
1488 
1489     // jq = jq | 0x1
1490     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1491   }
1492 
1493   // int ia = (int)LHS;
1494   SDValue ia = LHS;
1495 
1496   // int ib, (int)RHS;
1497   SDValue ib = RHS;
1498 
1499   // float fa = (float)ia;
1500   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1501 
1502   // float fb = (float)ib;
1503   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1504 
1505   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1506                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1507 
1508   // fq = trunc(fq);
1509   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1510 
1511   // float fqneg = -fq;
1512   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1513 
1514   // float fr = mad(fqneg, fb, fa);
1515   unsigned OpCode = Subtarget->hasFP32Denormals() ?
1516                     (unsigned)AMDGPUISD::FMAD_FTZ :
1517                     (unsigned)ISD::FMAD;
1518   SDValue fr = DAG.getNode(OpCode, DL, FltVT, fqneg, fb, fa);
1519 
1520   // int iq = (int)fq;
1521   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1522 
1523   // fr = fabs(fr);
1524   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1525 
1526   // fb = fabs(fb);
1527   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1528 
1529   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1530 
1531   // int cv = fr >= fb;
1532   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1533 
1534   // jq = (cv ? jq : 0);
1535   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1536 
1537   // dst = iq + jq;
1538   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1539 
1540   // Rem needs compensation, it's easier to recompute it
1541   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1542   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1543 
1544   // Truncate to number of bits this divide really is.
1545   if (Sign) {
1546     SDValue InRegSize
1547       = DAG.getValueType(EVT::getIntegerVT(*DAG.getContext(), DivBits));
1548     Div = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Div, InRegSize);
1549     Rem = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, VT, Rem, InRegSize);
1550   } else {
1551     SDValue TruncMask = DAG.getConstant((UINT64_C(1) << DivBits) - 1, DL, VT);
1552     Div = DAG.getNode(ISD::AND, DL, VT, Div, TruncMask);
1553     Rem = DAG.getNode(ISD::AND, DL, VT, Rem, TruncMask);
1554   }
1555 
1556   return DAG.getMergeValues({ Div, Rem }, DL);
1557 }
1558 
1559 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1560                                       SelectionDAG &DAG,
1561                                       SmallVectorImpl<SDValue> &Results) const {
1562   SDLoc DL(Op);
1563   EVT VT = Op.getValueType();
1564 
1565   assert(VT == MVT::i64 && "LowerUDIVREM64 expects an i64");
1566 
1567   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1568 
1569   SDValue One = DAG.getConstant(1, DL, HalfVT);
1570   SDValue Zero = DAG.getConstant(0, DL, HalfVT);
1571 
1572   //HiLo split
1573   SDValue LHS = Op.getOperand(0);
1574   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1575   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, One);
1576 
1577   SDValue RHS = Op.getOperand(1);
1578   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1579   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, One);
1580 
1581   if (DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1582       DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1583 
1584     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1585                               LHS_Lo, RHS_Lo);
1586 
1587     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), Zero});
1588     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), Zero});
1589 
1590     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1591     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1592     return;
1593   }
1594 
1595   if (isTypeLegal(MVT::i64)) {
1596     // Compute denominator reciprocal.
1597     unsigned FMAD = Subtarget->hasFP32Denormals() ?
1598                     (unsigned)AMDGPUISD::FMAD_FTZ :
1599                     (unsigned)ISD::FMAD;
1600 
1601     SDValue Cvt_Lo = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Lo);
1602     SDValue Cvt_Hi = DAG.getNode(ISD::UINT_TO_FP, DL, MVT::f32, RHS_Hi);
1603     SDValue Mad1 = DAG.getNode(FMAD, DL, MVT::f32, Cvt_Hi,
1604       DAG.getConstantFP(APInt(32, 0x4f800000).bitsToFloat(), DL, MVT::f32),
1605       Cvt_Lo);
1606     SDValue Rcp = DAG.getNode(AMDGPUISD::RCP, DL, MVT::f32, Mad1);
1607     SDValue Mul1 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Rcp,
1608       DAG.getConstantFP(APInt(32, 0x5f7ffffc).bitsToFloat(), DL, MVT::f32));
1609     SDValue Mul2 = DAG.getNode(ISD::FMUL, DL, MVT::f32, Mul1,
1610       DAG.getConstantFP(APInt(32, 0x2f800000).bitsToFloat(), DL, MVT::f32));
1611     SDValue Trunc = DAG.getNode(ISD::FTRUNC, DL, MVT::f32, Mul2);
1612     SDValue Mad2 = DAG.getNode(FMAD, DL, MVT::f32, Trunc,
1613       DAG.getConstantFP(APInt(32, 0xcf800000).bitsToFloat(), DL, MVT::f32),
1614       Mul1);
1615     SDValue Rcp_Lo = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Mad2);
1616     SDValue Rcp_Hi = DAG.getNode(ISD::FP_TO_UINT, DL, HalfVT, Trunc);
1617     SDValue Rcp64 = DAG.getBitcast(VT,
1618                         DAG.getBuildVector(MVT::v2i32, DL, {Rcp_Lo, Rcp_Hi}));
1619 
1620     SDValue Zero64 = DAG.getConstant(0, DL, VT);
1621     SDValue One64  = DAG.getConstant(1, DL, VT);
1622     SDValue Zero1 = DAG.getConstant(0, DL, MVT::i1);
1623     SDVTList HalfCarryVT = DAG.getVTList(HalfVT, MVT::i1);
1624 
1625     SDValue Neg_RHS = DAG.getNode(ISD::SUB, DL, VT, Zero64, RHS);
1626     SDValue Mullo1 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Rcp64);
1627     SDValue Mulhi1 = DAG.getNode(ISD::MULHU, DL, VT, Rcp64, Mullo1);
1628     SDValue Mulhi1_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1629                                     Zero);
1630     SDValue Mulhi1_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi1,
1631                                     One);
1632 
1633     SDValue Add1_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Lo,
1634                                   Mulhi1_Lo, Zero1);
1635     SDValue Add1_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Rcp_Hi,
1636                                   Mulhi1_Hi, Add1_Lo.getValue(1));
1637     SDValue Add1_HiNc = DAG.getNode(ISD::ADD, DL, HalfVT, Rcp_Hi, Mulhi1_Hi);
1638     SDValue Add1 = DAG.getBitcast(VT,
1639                         DAG.getBuildVector(MVT::v2i32, DL, {Add1_Lo, Add1_Hi}));
1640 
1641     SDValue Mullo2 = DAG.getNode(ISD::MUL, DL, VT, Neg_RHS, Add1);
1642     SDValue Mulhi2 = DAG.getNode(ISD::MULHU, DL, VT, Add1, Mullo2);
1643     SDValue Mulhi2_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1644                                     Zero);
1645     SDValue Mulhi2_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mulhi2,
1646                                     One);
1647 
1648     SDValue Add2_Lo = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_Lo,
1649                                   Mulhi2_Lo, Zero1);
1650     SDValue Add2_HiC = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add1_HiNc,
1651                                    Mulhi2_Hi, Add1_Lo.getValue(1));
1652     SDValue Add2_Hi = DAG.getNode(ISD::ADDCARRY, DL, HalfCarryVT, Add2_HiC,
1653                                   Zero, Add2_Lo.getValue(1));
1654     SDValue Add2 = DAG.getBitcast(VT,
1655                         DAG.getBuildVector(MVT::v2i32, DL, {Add2_Lo, Add2_Hi}));
1656     SDValue Mulhi3 = DAG.getNode(ISD::MULHU, DL, VT, LHS, Add2);
1657 
1658     SDValue Mul3 = DAG.getNode(ISD::MUL, DL, VT, RHS, Mulhi3);
1659 
1660     SDValue Mul3_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, Zero);
1661     SDValue Mul3_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, Mul3, One);
1662     SDValue Sub1_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Lo,
1663                                   Mul3_Lo, Zero1);
1664     SDValue Sub1_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, LHS_Hi,
1665                                   Mul3_Hi, Sub1_Lo.getValue(1));
1666     SDValue Sub1_Mi = DAG.getNode(ISD::SUB, DL, HalfVT, LHS_Hi, Mul3_Hi);
1667     SDValue Sub1 = DAG.getBitcast(VT,
1668                         DAG.getBuildVector(MVT::v2i32, DL, {Sub1_Lo, Sub1_Hi}));
1669 
1670     SDValue MinusOne = DAG.getConstant(0xffffffffu, DL, HalfVT);
1671     SDValue C1 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, MinusOne, Zero,
1672                                  ISD::SETUGE);
1673     SDValue C2 = DAG.getSelectCC(DL, Sub1_Lo, RHS_Lo, MinusOne, Zero,
1674                                  ISD::SETUGE);
1675     SDValue C3 = DAG.getSelectCC(DL, Sub1_Hi, RHS_Hi, C2, C1, ISD::SETEQ);
1676 
1677     // TODO: Here and below portions of the code can be enclosed into if/endif.
1678     // Currently control flow is unconditional and we have 4 selects after
1679     // potential endif to substitute PHIs.
1680 
1681     // if C3 != 0 ...
1682     SDValue Sub2_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Lo,
1683                                   RHS_Lo, Zero1);
1684     SDValue Sub2_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub1_Mi,
1685                                   RHS_Hi, Sub1_Lo.getValue(1));
1686     SDValue Sub2_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1687                                   Zero, Sub2_Lo.getValue(1));
1688     SDValue Sub2 = DAG.getBitcast(VT,
1689                         DAG.getBuildVector(MVT::v2i32, DL, {Sub2_Lo, Sub2_Hi}));
1690 
1691     SDValue Add3 = DAG.getNode(ISD::ADD, DL, VT, Mulhi3, One64);
1692 
1693     SDValue C4 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, MinusOne, Zero,
1694                                  ISD::SETUGE);
1695     SDValue C5 = DAG.getSelectCC(DL, Sub2_Lo, RHS_Lo, MinusOne, Zero,
1696                                  ISD::SETUGE);
1697     SDValue C6 = DAG.getSelectCC(DL, Sub2_Hi, RHS_Hi, C5, C4, ISD::SETEQ);
1698 
1699     // if (C6 != 0)
1700     SDValue Add4 = DAG.getNode(ISD::ADD, DL, VT, Add3, One64);
1701 
1702     SDValue Sub3_Lo = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Lo,
1703                                   RHS_Lo, Zero1);
1704     SDValue Sub3_Mi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub2_Mi,
1705                                   RHS_Hi, Sub2_Lo.getValue(1));
1706     SDValue Sub3_Hi = DAG.getNode(ISD::SUBCARRY, DL, HalfCarryVT, Sub3_Mi,
1707                                   Zero, Sub3_Lo.getValue(1));
1708     SDValue Sub3 = DAG.getBitcast(VT,
1709                         DAG.getBuildVector(MVT::v2i32, DL, {Sub3_Lo, Sub3_Hi}));
1710 
1711     // endif C6
1712     // endif C3
1713 
1714     SDValue Sel1 = DAG.getSelectCC(DL, C6, Zero, Add4, Add3, ISD::SETNE);
1715     SDValue Div  = DAG.getSelectCC(DL, C3, Zero, Sel1, Mulhi3, ISD::SETNE);
1716 
1717     SDValue Sel2 = DAG.getSelectCC(DL, C6, Zero, Sub3, Sub2, ISD::SETNE);
1718     SDValue Rem  = DAG.getSelectCC(DL, C3, Zero, Sel2, Sub1, ISD::SETNE);
1719 
1720     Results.push_back(Div);
1721     Results.push_back(Rem);
1722 
1723     return;
1724   }
1725 
1726   // r600 expandion.
1727   // Get Speculative values
1728   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1729   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1730 
1731   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, Zero, REM_Part, LHS_Hi, ISD::SETEQ);
1732   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, Zero});
1733   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1734 
1735   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, Zero, DIV_Part, Zero, ISD::SETEQ);
1736   SDValue DIV_Lo = Zero;
1737 
1738   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1739 
1740   for (unsigned i = 0; i < halfBitWidth; ++i) {
1741     const unsigned bitPos = halfBitWidth - i - 1;
1742     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1743     // Get value of high bit
1744     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1745     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, One);
1746     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1747 
1748     // Shift
1749     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1750     // Add LHS high bit
1751     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1752 
1753     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1754     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, Zero, ISD::SETUGE);
1755 
1756     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1757 
1758     // Update REM
1759     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1760     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1761   }
1762 
1763   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1764   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1765   Results.push_back(DIV);
1766   Results.push_back(REM);
1767 }
1768 
1769 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1770                                            SelectionDAG &DAG) const {
1771   SDLoc DL(Op);
1772   EVT VT = Op.getValueType();
1773 
1774   if (VT == MVT::i64) {
1775     SmallVector<SDValue, 2> Results;
1776     LowerUDIVREM64(Op, DAG, Results);
1777     return DAG.getMergeValues(Results, DL);
1778   }
1779 
1780   if (VT == MVT::i32) {
1781     if (SDValue Res = LowerDIVREM24(Op, DAG, false))
1782       return Res;
1783   }
1784 
1785   SDValue Num = Op.getOperand(0);
1786   SDValue Den = Op.getOperand(1);
1787 
1788   // RCP =  URECIP(Den) = 2^32 / Den + e
1789   // e is rounding error.
1790   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1791 
1792   // RCP_LO = mul(RCP, Den) */
1793   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1794 
1795   // RCP_HI = mulhu (RCP, Den) */
1796   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1797 
1798   // NEG_RCP_LO = -RCP_LO
1799   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1800                                                      RCP_LO);
1801 
1802   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1803   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1804                                            NEG_RCP_LO, RCP_LO,
1805                                            ISD::SETEQ);
1806   // Calculate the rounding error from the URECIP instruction
1807   // E = mulhu(ABS_RCP_LO, RCP)
1808   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1809 
1810   // RCP_A_E = RCP + E
1811   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1812 
1813   // RCP_S_E = RCP - E
1814   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1815 
1816   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1817   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1818                                      RCP_A_E, RCP_S_E,
1819                                      ISD::SETEQ);
1820   // Quotient = mulhu(Tmp0, Num)
1821   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1822 
1823   // Num_S_Remainder = Quotient * Den
1824   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1825 
1826   // Remainder = Num - Num_S_Remainder
1827   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1828 
1829   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1830   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1831                                                  DAG.getConstant(-1, DL, VT),
1832                                                  DAG.getConstant(0, DL, VT),
1833                                                  ISD::SETUGE);
1834   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1835   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1836                                                   Num_S_Remainder,
1837                                                   DAG.getConstant(-1, DL, VT),
1838                                                   DAG.getConstant(0, DL, VT),
1839                                                   ISD::SETUGE);
1840   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1841   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1842                                                Remainder_GE_Zero);
1843 
1844   // Calculate Division result:
1845 
1846   // Quotient_A_One = Quotient + 1
1847   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1848                                        DAG.getConstant(1, DL, VT));
1849 
1850   // Quotient_S_One = Quotient - 1
1851   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1852                                        DAG.getConstant(1, DL, VT));
1853 
1854   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1855   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1856                                      Quotient, Quotient_A_One, ISD::SETEQ);
1857 
1858   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1859   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1860                             Quotient_S_One, Div, ISD::SETEQ);
1861 
1862   // Calculate Rem result:
1863 
1864   // Remainder_S_Den = Remainder - Den
1865   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1866 
1867   // Remainder_A_Den = Remainder + Den
1868   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1869 
1870   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1871   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1872                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1873 
1874   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1875   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1876                             Remainder_A_Den, Rem, ISD::SETEQ);
1877   SDValue Ops[2] = {
1878     Div,
1879     Rem
1880   };
1881   return DAG.getMergeValues(Ops, DL);
1882 }
1883 
1884 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
1885                                            SelectionDAG &DAG) const {
1886   SDLoc DL(Op);
1887   EVT VT = Op.getValueType();
1888 
1889   SDValue LHS = Op.getOperand(0);
1890   SDValue RHS = Op.getOperand(1);
1891 
1892   SDValue Zero = DAG.getConstant(0, DL, VT);
1893   SDValue NegOne = DAG.getConstant(-1, DL, VT);
1894 
1895   if (VT == MVT::i32) {
1896     if (SDValue Res = LowerDIVREM24(Op, DAG, true))
1897       return Res;
1898   }
1899 
1900   if (VT == MVT::i64 &&
1901       DAG.ComputeNumSignBits(LHS) > 32 &&
1902       DAG.ComputeNumSignBits(RHS) > 32) {
1903     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1904 
1905     //HiLo split
1906     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1907     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1908     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1909                                  LHS_Lo, RHS_Lo);
1910     SDValue Res[2] = {
1911       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
1912       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
1913     };
1914     return DAG.getMergeValues(Res, DL);
1915   }
1916 
1917   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
1918   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
1919   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
1920   SDValue RSign = LHSign; // Remainder sign is the same as LHS
1921 
1922   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
1923   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
1924 
1925   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
1926   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
1927 
1928   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
1929   SDValue Rem = Div.getValue(1);
1930 
1931   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
1932   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
1933 
1934   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
1935   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
1936 
1937   SDValue Res[2] = {
1938     Div,
1939     Rem
1940   };
1941   return DAG.getMergeValues(Res, DL);
1942 }
1943 
1944 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
1945 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
1946   SDLoc SL(Op);
1947   EVT VT = Op.getValueType();
1948   SDValue X = Op.getOperand(0);
1949   SDValue Y = Op.getOperand(1);
1950 
1951   // TODO: Should this propagate fast-math-flags?
1952 
1953   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
1954   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
1955   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
1956 
1957   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
1958 }
1959 
1960 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
1961   SDLoc SL(Op);
1962   SDValue Src = Op.getOperand(0);
1963 
1964   // result = trunc(src)
1965   // if (src > 0.0 && src != result)
1966   //   result += 1.0
1967 
1968   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
1969 
1970   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
1971   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
1972 
1973   EVT SetCCVT =
1974       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
1975 
1976   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
1977   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
1978   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
1979 
1980   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
1981   // TODO: Should this propagate fast-math-flags?
1982   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
1983 }
1984 
1985 static SDValue extractF64Exponent(SDValue Hi, const SDLoc &SL,
1986                                   SelectionDAG &DAG) {
1987   const unsigned FractBits = 52;
1988   const unsigned ExpBits = 11;
1989 
1990   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
1991                                 Hi,
1992                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
1993                                 DAG.getConstant(ExpBits, SL, MVT::i32));
1994   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
1995                             DAG.getConstant(1023, SL, MVT::i32));
1996 
1997   return Exp;
1998 }
1999 
2000 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
2001   SDLoc SL(Op);
2002   SDValue Src = Op.getOperand(0);
2003 
2004   assert(Op.getValueType() == MVT::f64);
2005 
2006   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2007   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2008 
2009   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2010 
2011   // Extract the upper half, since this is where we will find the sign and
2012   // exponent.
2013   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
2014 
2015   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2016 
2017   const unsigned FractBits = 52;
2018 
2019   // Extract the sign bit.
2020   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
2021   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
2022 
2023   // Extend back to 64-bits.
2024   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
2025   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
2026 
2027   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
2028   const SDValue FractMask
2029     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
2030 
2031   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
2032   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
2033   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
2034 
2035   EVT SetCCVT =
2036       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2037 
2038   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
2039 
2040   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2041   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2042 
2043   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
2044   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
2045 
2046   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
2047 }
2048 
2049 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
2050   SDLoc SL(Op);
2051   SDValue Src = Op.getOperand(0);
2052 
2053   assert(Op.getValueType() == MVT::f64);
2054 
2055   APFloat C1Val(APFloat::IEEEdouble(), "0x1.0p+52");
2056   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
2057   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
2058 
2059   // TODO: Should this propagate fast-math-flags?
2060 
2061   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
2062   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
2063 
2064   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
2065 
2066   APFloat C2Val(APFloat::IEEEdouble(), "0x1.fffffffffffffp+51");
2067   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
2068 
2069   EVT SetCCVT =
2070       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2071   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
2072 
2073   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
2074 }
2075 
2076 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
2077   // FNEARBYINT and FRINT are the same, except in their handling of FP
2078   // exceptions. Those aren't really meaningful for us, and OpenCL only has
2079   // rint, so just treat them as equivalent.
2080   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
2081 }
2082 
2083 // XXX - May require not supporting f32 denormals?
2084 
2085 // Don't handle v2f16. The extra instructions to scalarize and repack around the
2086 // compare and vselect end up producing worse code than scalarizing the whole
2087 // operation.
2088 SDValue AMDGPUTargetLowering::LowerFROUND32_16(SDValue Op, SelectionDAG &DAG) const {
2089   SDLoc SL(Op);
2090   SDValue X = Op.getOperand(0);
2091   EVT VT = Op.getValueType();
2092 
2093   SDValue T = DAG.getNode(ISD::FTRUNC, SL, VT, X);
2094 
2095   // TODO: Should this propagate fast-math-flags?
2096 
2097   SDValue Diff = DAG.getNode(ISD::FSUB, SL, VT, X, T);
2098 
2099   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, VT, Diff);
2100 
2101   const SDValue Zero = DAG.getConstantFP(0.0, SL, VT);
2102   const SDValue One = DAG.getConstantFP(1.0, SL, VT);
2103   const SDValue Half = DAG.getConstantFP(0.5, SL, VT);
2104 
2105   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, VT, One, X);
2106 
2107   EVT SetCCVT =
2108       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
2109 
2110   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
2111 
2112   SDValue Sel = DAG.getNode(ISD::SELECT, SL, VT, Cmp, SignOne, Zero);
2113 
2114   return DAG.getNode(ISD::FADD, SL, VT, T, Sel);
2115 }
2116 
2117 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
2118   SDLoc SL(Op);
2119   SDValue X = Op.getOperand(0);
2120 
2121   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
2122 
2123   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2124   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2125   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
2126   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
2127   EVT SetCCVT =
2128       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
2129 
2130   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
2131 
2132   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
2133 
2134   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
2135 
2136   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
2137                                        MVT::i64);
2138 
2139   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
2140   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
2141                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
2142                                           MVT::i64),
2143                           Exp);
2144 
2145   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
2146   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
2147                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
2148                               ISD::SETNE);
2149 
2150   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
2151                              D, DAG.getConstant(0, SL, MVT::i64));
2152   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
2153 
2154   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
2155   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
2156 
2157   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
2158   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
2159   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
2160 
2161   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
2162                             ExpEqNegOne,
2163                             DAG.getConstantFP(1.0, SL, MVT::f64),
2164                             DAG.getConstantFP(0.0, SL, MVT::f64));
2165 
2166   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
2167 
2168   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
2169   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
2170 
2171   return K;
2172 }
2173 
2174 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
2175   EVT VT = Op.getValueType();
2176 
2177   if (VT == MVT::f32 || VT == MVT::f16)
2178     return LowerFROUND32_16(Op, DAG);
2179 
2180   if (VT == MVT::f64)
2181     return LowerFROUND64(Op, DAG);
2182 
2183   llvm_unreachable("unhandled type");
2184 }
2185 
2186 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
2187   SDLoc SL(Op);
2188   SDValue Src = Op.getOperand(0);
2189 
2190   // result = trunc(src);
2191   // if (src < 0.0 && src != result)
2192   //   result += -1.0.
2193 
2194   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2195 
2196   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
2197   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
2198 
2199   EVT SetCCVT =
2200       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
2201 
2202   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
2203   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
2204   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
2205 
2206   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
2207   // TODO: Should this propagate fast-math-flags?
2208   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
2209 }
2210 
2211 SDValue AMDGPUTargetLowering::LowerFLOG(SDValue Op, SelectionDAG &DAG,
2212                                         double Log2BaseInverted) const {
2213   EVT VT = Op.getValueType();
2214 
2215   SDLoc SL(Op);
2216   SDValue Operand = Op.getOperand(0);
2217   SDValue Log2Operand = DAG.getNode(ISD::FLOG2, SL, VT, Operand);
2218   SDValue Log2BaseInvertedOperand = DAG.getConstantFP(Log2BaseInverted, SL, VT);
2219 
2220   return DAG.getNode(ISD::FMUL, SL, VT, Log2Operand, Log2BaseInvertedOperand);
2221 }
2222 
2223 // Return M_LOG2E of appropriate type
2224 static SDValue getLog2EVal(SelectionDAG &DAG, const SDLoc &SL, EVT VT) {
2225   switch (VT.getScalarType().getSimpleVT().SimpleTy) {
2226   case MVT::f32:
2227     return DAG.getConstantFP(1.44269504088896340735992468100189214f, SL, VT);
2228   case MVT::f16:
2229     return DAG.getConstantFP(
2230       APFloat(APFloat::IEEEhalf(), "1.44269504088896340735992468100189214"),
2231       SL, VT);
2232   case MVT::f64:
2233     return DAG.getConstantFP(
2234       APFloat(APFloat::IEEEdouble(), "0x1.71547652b82fep+0"), SL, VT);
2235   default:
2236     llvm_unreachable("unsupported fp type");
2237   }
2238 }
2239 
2240 // exp2(M_LOG2E_F * f);
2241 SDValue AMDGPUTargetLowering::lowerFEXP(SDValue Op, SelectionDAG &DAG) const {
2242   EVT VT = Op.getValueType();
2243   SDLoc SL(Op);
2244   SDValue Src = Op.getOperand(0);
2245 
2246   const SDValue K = getLog2EVal(DAG, SL, VT);
2247   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Src, K, Op->getFlags());
2248   return DAG.getNode(ISD::FEXP2, SL, VT, Mul, Op->getFlags());
2249 }
2250 
2251 static bool isCtlzOpc(unsigned Opc) {
2252   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2253 }
2254 
2255 static bool isCttzOpc(unsigned Opc) {
2256   return Opc == ISD::CTTZ || Opc == ISD::CTTZ_ZERO_UNDEF;
2257 }
2258 
2259 SDValue AMDGPUTargetLowering::LowerCTLZ_CTTZ(SDValue Op, SelectionDAG &DAG) const {
2260   SDLoc SL(Op);
2261   SDValue Src = Op.getOperand(0);
2262   bool ZeroUndef = Op.getOpcode() == ISD::CTTZ_ZERO_UNDEF ||
2263                    Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
2264 
2265   unsigned ISDOpc, NewOpc;
2266   if (isCtlzOpc(Op.getOpcode())) {
2267     ISDOpc = ISD::CTLZ_ZERO_UNDEF;
2268     NewOpc = AMDGPUISD::FFBH_U32;
2269   } else if (isCttzOpc(Op.getOpcode())) {
2270     ISDOpc = ISD::CTTZ_ZERO_UNDEF;
2271     NewOpc = AMDGPUISD::FFBL_B32;
2272   } else
2273     llvm_unreachable("Unexpected OPCode!!!");
2274 
2275 
2276   if (ZeroUndef && Src.getValueType() == MVT::i32)
2277     return DAG.getNode(NewOpc, SL, MVT::i32, Src);
2278 
2279   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2280 
2281   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2282   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
2283 
2284   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
2285   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
2286 
2287   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2288                                    *DAG.getContext(), MVT::i32);
2289 
2290   SDValue HiOrLo = isCtlzOpc(Op.getOpcode()) ? Hi : Lo;
2291   SDValue Hi0orLo0 = DAG.getSetCC(SL, SetCCVT, HiOrLo, Zero, ISD::SETEQ);
2292 
2293   SDValue OprLo = DAG.getNode(ISDOpc, SL, MVT::i32, Lo);
2294   SDValue OprHi = DAG.getNode(ISDOpc, SL, MVT::i32, Hi);
2295 
2296   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
2297   SDValue Add, NewOpr;
2298   if (isCtlzOpc(Op.getOpcode())) {
2299     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprLo, Bits32);
2300     // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
2301     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprHi);
2302   } else {
2303     Add = DAG.getNode(ISD::ADD, SL, MVT::i32, OprHi, Bits32);
2304     // cttz(x) = lo_32(x) == 0 ? cttz(hi_32(x)) + 32 : cttz(lo_32(x))
2305     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0orLo0, Add, OprLo);
2306   }
2307 
2308   if (!ZeroUndef) {
2309     // Test if the full 64-bit input is zero.
2310 
2311     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
2312     // which we probably don't want.
2313     SDValue LoOrHi = isCtlzOpc(Op.getOpcode()) ? Lo : Hi;
2314     SDValue Lo0OrHi0 = DAG.getSetCC(SL, SetCCVT, LoOrHi, Zero, ISD::SETEQ);
2315     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0OrHi0, Hi0orLo0);
2316 
2317     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
2318     // with the same cycles, otherwise it is slower.
2319     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
2320     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
2321 
2322     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
2323 
2324     // The instruction returns -1 for 0 input, but the defined intrinsic
2325     // behavior is to return the number of bits.
2326     NewOpr = DAG.getNode(ISD::SELECT, SL, MVT::i32,
2327                          SrcIsZero, Bits32, NewOpr);
2328   }
2329 
2330   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewOpr);
2331 }
2332 
2333 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
2334                                                bool Signed) const {
2335   // Unsigned
2336   // cul2f(ulong u)
2337   //{
2338   //  uint lz = clz(u);
2339   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
2340   //  u = (u << lz) & 0x7fffffffffffffffUL;
2341   //  ulong t = u & 0xffffffffffUL;
2342   //  uint v = (e << 23) | (uint)(u >> 40);
2343   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
2344   //  return as_float(v + r);
2345   //}
2346   // Signed
2347   // cl2f(long l)
2348   //{
2349   //  long s = l >> 63;
2350   //  float r = cul2f((l + s) ^ s);
2351   //  return s ? -r : r;
2352   //}
2353 
2354   SDLoc SL(Op);
2355   SDValue Src = Op.getOperand(0);
2356   SDValue L = Src;
2357 
2358   SDValue S;
2359   if (Signed) {
2360     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
2361     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
2362 
2363     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
2364     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
2365   }
2366 
2367   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
2368                                    *DAG.getContext(), MVT::f32);
2369 
2370 
2371   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
2372   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
2373   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
2374   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
2375 
2376   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
2377   SDValue E = DAG.getSelect(SL, MVT::i32,
2378     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
2379     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
2380     ZeroI32);
2381 
2382   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
2383     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
2384     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
2385 
2386   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
2387                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
2388 
2389   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
2390                              U, DAG.getConstant(40, SL, MVT::i64));
2391 
2392   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
2393     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
2394     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
2395 
2396   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
2397   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
2398   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
2399 
2400   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2401 
2402   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
2403 
2404   SDValue R = DAG.getSelect(SL, MVT::i32,
2405     RCmp,
2406     One,
2407     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
2408   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
2409   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
2410 
2411   if (!Signed)
2412     return R;
2413 
2414   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
2415   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
2416 }
2417 
2418 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
2419                                                bool Signed) const {
2420   SDLoc SL(Op);
2421   SDValue Src = Op.getOperand(0);
2422 
2423   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
2424 
2425   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2426                            DAG.getConstant(0, SL, MVT::i32));
2427   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
2428                            DAG.getConstant(1, SL, MVT::i32));
2429 
2430   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
2431                               SL, MVT::f64, Hi);
2432 
2433   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
2434 
2435   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
2436                               DAG.getConstant(32, SL, MVT::i32));
2437   // TODO: Should this propagate fast-math-flags?
2438   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
2439 }
2440 
2441 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
2442                                                SelectionDAG &DAG) const {
2443   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2444          "operation should be legal");
2445 
2446   // TODO: Factor out code common with LowerSINT_TO_FP.
2447 
2448   EVT DestVT = Op.getValueType();
2449   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2450     SDLoc DL(Op);
2451     SDValue Src = Op.getOperand(0);
2452 
2453     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2454     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2455     SDValue FPRound =
2456         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2457 
2458     return FPRound;
2459   }
2460 
2461   if (DestVT == MVT::f32)
2462     return LowerINT_TO_FP32(Op, DAG, false);
2463 
2464   assert(DestVT == MVT::f64);
2465   return LowerINT_TO_FP64(Op, DAG, false);
2466 }
2467 
2468 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
2469                                               SelectionDAG &DAG) const {
2470   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
2471          "operation should be legal");
2472 
2473   // TODO: Factor out code common with LowerUINT_TO_FP.
2474 
2475   EVT DestVT = Op.getValueType();
2476   if (Subtarget->has16BitInsts() && DestVT == MVT::f16) {
2477     SDLoc DL(Op);
2478     SDValue Src = Op.getOperand(0);
2479 
2480     SDValue IntToFp32 = DAG.getNode(Op.getOpcode(), DL, MVT::f32, Src);
2481     SDValue FPRoundFlag = DAG.getIntPtrConstant(0, SDLoc(Op));
2482     SDValue FPRound =
2483         DAG.getNode(ISD::FP_ROUND, DL, MVT::f16, IntToFp32, FPRoundFlag);
2484 
2485     return FPRound;
2486   }
2487 
2488   if (DestVT == MVT::f32)
2489     return LowerINT_TO_FP32(Op, DAG, true);
2490 
2491   assert(DestVT == MVT::f64);
2492   return LowerINT_TO_FP64(Op, DAG, true);
2493 }
2494 
2495 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
2496                                                bool Signed) const {
2497   SDLoc SL(Op);
2498 
2499   SDValue Src = Op.getOperand(0);
2500 
2501   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
2502 
2503   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
2504                                  MVT::f64);
2505   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
2506                                  MVT::f64);
2507   // TODO: Should this propagate fast-math-flags?
2508   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
2509 
2510   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
2511 
2512 
2513   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
2514 
2515   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2516                            MVT::i32, FloorMul);
2517   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2518 
2519   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2520 
2521   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2522 }
2523 
2524 SDValue AMDGPUTargetLowering::LowerFP_TO_FP16(SDValue Op, SelectionDAG &DAG) const {
2525   SDLoc DL(Op);
2526   SDValue N0 = Op.getOperand(0);
2527 
2528   // Convert to target node to get known bits
2529   if (N0.getValueType() == MVT::f32)
2530     return DAG.getNode(AMDGPUISD::FP_TO_FP16, DL, Op.getValueType(), N0);
2531 
2532   if (getTargetMachine().Options.UnsafeFPMath) {
2533     // There is a generic expand for FP_TO_FP16 with unsafe fast math.
2534     return SDValue();
2535   }
2536 
2537   assert(N0.getSimpleValueType() == MVT::f64);
2538 
2539   // f64 -> f16 conversion using round-to-nearest-even rounding mode.
2540   const unsigned ExpMask = 0x7ff;
2541   const unsigned ExpBiasf64 = 1023;
2542   const unsigned ExpBiasf16 = 15;
2543   SDValue Zero = DAG.getConstant(0, DL, MVT::i32);
2544   SDValue One = DAG.getConstant(1, DL, MVT::i32);
2545   SDValue U = DAG.getNode(ISD::BITCAST, DL, MVT::i64, N0);
2546   SDValue UH = DAG.getNode(ISD::SRL, DL, MVT::i64, U,
2547                            DAG.getConstant(32, DL, MVT::i64));
2548   UH = DAG.getZExtOrTrunc(UH, DL, MVT::i32);
2549   U = DAG.getZExtOrTrunc(U, DL, MVT::i32);
2550   SDValue E = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2551                           DAG.getConstant(20, DL, MVT::i64));
2552   E = DAG.getNode(ISD::AND, DL, MVT::i32, E,
2553                   DAG.getConstant(ExpMask, DL, MVT::i32));
2554   // Subtract the fp64 exponent bias (1023) to get the real exponent and
2555   // add the f16 bias (15) to get the biased exponent for the f16 format.
2556   E = DAG.getNode(ISD::ADD, DL, MVT::i32, E,
2557                   DAG.getConstant(-ExpBiasf64 + ExpBiasf16, DL, MVT::i32));
2558 
2559   SDValue M = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2560                           DAG.getConstant(8, DL, MVT::i32));
2561   M = DAG.getNode(ISD::AND, DL, MVT::i32, M,
2562                   DAG.getConstant(0xffe, DL, MVT::i32));
2563 
2564   SDValue MaskedSig = DAG.getNode(ISD::AND, DL, MVT::i32, UH,
2565                                   DAG.getConstant(0x1ff, DL, MVT::i32));
2566   MaskedSig = DAG.getNode(ISD::OR, DL, MVT::i32, MaskedSig, U);
2567 
2568   SDValue Lo40Set = DAG.getSelectCC(DL, MaskedSig, Zero, Zero, One, ISD::SETEQ);
2569   M = DAG.getNode(ISD::OR, DL, MVT::i32, M, Lo40Set);
2570 
2571   // (M != 0 ? 0x0200 : 0) | 0x7c00;
2572   SDValue I = DAG.getNode(ISD::OR, DL, MVT::i32,
2573       DAG.getSelectCC(DL, M, Zero, DAG.getConstant(0x0200, DL, MVT::i32),
2574                       Zero, ISD::SETNE), DAG.getConstant(0x7c00, DL, MVT::i32));
2575 
2576   // N = M | (E << 12);
2577   SDValue N = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2578       DAG.getNode(ISD::SHL, DL, MVT::i32, E,
2579                   DAG.getConstant(12, DL, MVT::i32)));
2580 
2581   // B = clamp(1-E, 0, 13);
2582   SDValue OneSubExp = DAG.getNode(ISD::SUB, DL, MVT::i32,
2583                                   One, E);
2584   SDValue B = DAG.getNode(ISD::SMAX, DL, MVT::i32, OneSubExp, Zero);
2585   B = DAG.getNode(ISD::SMIN, DL, MVT::i32, B,
2586                   DAG.getConstant(13, DL, MVT::i32));
2587 
2588   SDValue SigSetHigh = DAG.getNode(ISD::OR, DL, MVT::i32, M,
2589                                    DAG.getConstant(0x1000, DL, MVT::i32));
2590 
2591   SDValue D = DAG.getNode(ISD::SRL, DL, MVT::i32, SigSetHigh, B);
2592   SDValue D0 = DAG.getNode(ISD::SHL, DL, MVT::i32, D, B);
2593   SDValue D1 = DAG.getSelectCC(DL, D0, SigSetHigh, One, Zero, ISD::SETNE);
2594   D = DAG.getNode(ISD::OR, DL, MVT::i32, D, D1);
2595 
2596   SDValue V = DAG.getSelectCC(DL, E, One, D, N, ISD::SETLT);
2597   SDValue VLow3 = DAG.getNode(ISD::AND, DL, MVT::i32, V,
2598                               DAG.getConstant(0x7, DL, MVT::i32));
2599   V = DAG.getNode(ISD::SRL, DL, MVT::i32, V,
2600                   DAG.getConstant(2, DL, MVT::i32));
2601   SDValue V0 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(3, DL, MVT::i32),
2602                                One, Zero, ISD::SETEQ);
2603   SDValue V1 = DAG.getSelectCC(DL, VLow3, DAG.getConstant(5, DL, MVT::i32),
2604                                One, Zero, ISD::SETGT);
2605   V1 = DAG.getNode(ISD::OR, DL, MVT::i32, V0, V1);
2606   V = DAG.getNode(ISD::ADD, DL, MVT::i32, V, V1);
2607 
2608   V = DAG.getSelectCC(DL, E, DAG.getConstant(30, DL, MVT::i32),
2609                       DAG.getConstant(0x7c00, DL, MVT::i32), V, ISD::SETGT);
2610   V = DAG.getSelectCC(DL, E, DAG.getConstant(1039, DL, MVT::i32),
2611                       I, V, ISD::SETEQ);
2612 
2613   // Extract the sign bit.
2614   SDValue Sign = DAG.getNode(ISD::SRL, DL, MVT::i32, UH,
2615                             DAG.getConstant(16, DL, MVT::i32));
2616   Sign = DAG.getNode(ISD::AND, DL, MVT::i32, Sign,
2617                      DAG.getConstant(0x8000, DL, MVT::i32));
2618 
2619   V = DAG.getNode(ISD::OR, DL, MVT::i32, Sign, V);
2620   return DAG.getZExtOrTrunc(V, DL, Op.getValueType());
2621 }
2622 
2623 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2624                                               SelectionDAG &DAG) const {
2625   SDValue Src = Op.getOperand(0);
2626 
2627   // TODO: Factor out code common with LowerFP_TO_UINT.
2628 
2629   EVT SrcVT = Src.getValueType();
2630   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2631     SDLoc DL(Op);
2632 
2633     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2634     SDValue FpToInt32 =
2635         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2636 
2637     return FpToInt32;
2638   }
2639 
2640   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2641     return LowerFP64_TO_INT(Op, DAG, true);
2642 
2643   return SDValue();
2644 }
2645 
2646 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2647                                               SelectionDAG &DAG) const {
2648   SDValue Src = Op.getOperand(0);
2649 
2650   // TODO: Factor out code common with LowerFP_TO_SINT.
2651 
2652   EVT SrcVT = Src.getValueType();
2653   if (Subtarget->has16BitInsts() && SrcVT == MVT::f16) {
2654     SDLoc DL(Op);
2655 
2656     SDValue FPExtend = DAG.getNode(ISD::FP_EXTEND, DL, MVT::f32, Src);
2657     SDValue FpToInt32 =
2658         DAG.getNode(Op.getOpcode(), DL, MVT::i64, FPExtend);
2659 
2660     return FpToInt32;
2661   }
2662 
2663   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2664     return LowerFP64_TO_INT(Op, DAG, false);
2665 
2666   return SDValue();
2667 }
2668 
2669 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2670                                                      SelectionDAG &DAG) const {
2671   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2672   MVT VT = Op.getSimpleValueType();
2673   MVT ScalarVT = VT.getScalarType();
2674 
2675   assert(VT.isVector());
2676 
2677   SDValue Src = Op.getOperand(0);
2678   SDLoc DL(Op);
2679 
2680   // TODO: Don't scalarize on Evergreen?
2681   unsigned NElts = VT.getVectorNumElements();
2682   SmallVector<SDValue, 8> Args;
2683   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2684 
2685   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2686   for (unsigned I = 0; I < NElts; ++I)
2687     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2688 
2689   return DAG.getBuildVector(VT, DL, Args);
2690 }
2691 
2692 //===----------------------------------------------------------------------===//
2693 // Custom DAG optimizations
2694 //===----------------------------------------------------------------------===//
2695 
2696 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2697   return AMDGPUTargetLowering::numBitsUnsigned(Op, DAG) <= 24;
2698 }
2699 
2700 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2701   EVT VT = Op.getValueType();
2702   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2703                                      // as unsigned 24-bit values.
2704     AMDGPUTargetLowering::numBitsSigned(Op, DAG) < 24;
2705 }
2706 
2707 static bool simplifyI24(SDNode *Node24, unsigned OpIdx,
2708                         TargetLowering::DAGCombinerInfo &DCI) {
2709 
2710   SelectionDAG &DAG = DCI.DAG;
2711   SDValue Op = Node24->getOperand(OpIdx);
2712   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2713   EVT VT = Op.getValueType();
2714 
2715   APInt Demanded = APInt::getLowBitsSet(VT.getSizeInBits(), 24);
2716   APInt KnownZero, KnownOne;
2717   TargetLowering::TargetLoweringOpt TLO(DAG, true, true);
2718   if (TLI.SimplifyDemandedBits(Node24, OpIdx, Demanded, DCI, TLO))
2719     return true;
2720 
2721   return false;
2722 }
2723 
2724 template <typename IntTy>
2725 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0, uint32_t Offset,
2726                                uint32_t Width, const SDLoc &DL) {
2727   if (Width + Offset < 32) {
2728     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2729     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2730     return DAG.getConstant(Result, DL, MVT::i32);
2731   }
2732 
2733   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2734 }
2735 
2736 static bool hasVolatileUser(SDNode *Val) {
2737   for (SDNode *U : Val->uses()) {
2738     if (MemSDNode *M = dyn_cast<MemSDNode>(U)) {
2739       if (M->isVolatile())
2740         return true;
2741     }
2742   }
2743 
2744   return false;
2745 }
2746 
2747 bool AMDGPUTargetLowering::shouldCombineMemoryType(EVT VT) const {
2748   // i32 vectors are the canonical memory type.
2749   if (VT.getScalarType() == MVT::i32 || isTypeLegal(VT))
2750     return false;
2751 
2752   if (!VT.isByteSized())
2753     return false;
2754 
2755   unsigned Size = VT.getStoreSize();
2756 
2757   if ((Size == 1 || Size == 2 || Size == 4) && !VT.isVector())
2758     return false;
2759 
2760   if (Size == 3 || (Size > 4 && (Size % 4 != 0)))
2761     return false;
2762 
2763   return true;
2764 }
2765 
2766 // Replace load of an illegal type with a store of a bitcast to a friendlier
2767 // type.
2768 SDValue AMDGPUTargetLowering::performLoadCombine(SDNode *N,
2769                                                  DAGCombinerInfo &DCI) const {
2770   if (!DCI.isBeforeLegalize())
2771     return SDValue();
2772 
2773   LoadSDNode *LN = cast<LoadSDNode>(N);
2774   if (LN->isVolatile() || !ISD::isNormalLoad(LN) || hasVolatileUser(LN))
2775     return SDValue();
2776 
2777   SDLoc SL(N);
2778   SelectionDAG &DAG = DCI.DAG;
2779   EVT VT = LN->getMemoryVT();
2780 
2781   unsigned Size = VT.getStoreSize();
2782   unsigned Align = LN->getAlignment();
2783   if (Align < Size && isTypeLegal(VT)) {
2784     bool IsFast;
2785     unsigned AS = LN->getAddressSpace();
2786 
2787     // Expand unaligned loads earlier than legalization. Due to visitation order
2788     // problems during legalization, the emitted instructions to pack and unpack
2789     // the bytes again are not eliminated in the case of an unaligned copy.
2790     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2791       if (VT.isVector())
2792         return scalarizeVectorLoad(LN, DAG);
2793 
2794       SDValue Ops[2];
2795       std::tie(Ops[0], Ops[1]) = expandUnalignedLoad(LN, DAG);
2796       return DAG.getMergeValues(Ops, SDLoc(N));
2797     }
2798 
2799     if (!IsFast)
2800       return SDValue();
2801   }
2802 
2803   if (!shouldCombineMemoryType(VT))
2804     return SDValue();
2805 
2806   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2807 
2808   SDValue NewLoad
2809     = DAG.getLoad(NewVT, SL, LN->getChain(),
2810                   LN->getBasePtr(), LN->getMemOperand());
2811 
2812   SDValue BC = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad);
2813   DCI.CombineTo(N, BC, NewLoad.getValue(1));
2814   return SDValue(N, 0);
2815 }
2816 
2817 // Replace store of an illegal type with a store of a bitcast to a friendlier
2818 // type.
2819 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2820                                                   DAGCombinerInfo &DCI) const {
2821   if (!DCI.isBeforeLegalize())
2822     return SDValue();
2823 
2824   StoreSDNode *SN = cast<StoreSDNode>(N);
2825   if (SN->isVolatile() || !ISD::isNormalStore(SN))
2826     return SDValue();
2827 
2828   EVT VT = SN->getMemoryVT();
2829   unsigned Size = VT.getStoreSize();
2830 
2831   SDLoc SL(N);
2832   SelectionDAG &DAG = DCI.DAG;
2833   unsigned Align = SN->getAlignment();
2834   if (Align < Size && isTypeLegal(VT)) {
2835     bool IsFast;
2836     unsigned AS = SN->getAddressSpace();
2837 
2838     // Expand unaligned stores earlier than legalization. Due to visitation
2839     // order problems during legalization, the emitted instructions to pack and
2840     // unpack the bytes again are not eliminated in the case of an unaligned
2841     // copy.
2842     if (!allowsMisalignedMemoryAccesses(VT, AS, Align, &IsFast)) {
2843       if (VT.isVector())
2844         return scalarizeVectorStore(SN, DAG);
2845 
2846       return expandUnalignedStore(SN, DAG);
2847     }
2848 
2849     if (!IsFast)
2850       return SDValue();
2851   }
2852 
2853   if (!shouldCombineMemoryType(VT))
2854     return SDValue();
2855 
2856   EVT NewVT = getEquivalentMemType(*DAG.getContext(), VT);
2857   SDValue Val = SN->getValue();
2858 
2859   //DCI.AddToWorklist(Val.getNode());
2860 
2861   bool OtherUses = !Val.hasOneUse();
2862   SDValue CastVal = DAG.getNode(ISD::BITCAST, SL, NewVT, Val);
2863   if (OtherUses) {
2864     SDValue CastBack = DAG.getNode(ISD::BITCAST, SL, VT, CastVal);
2865     DAG.ReplaceAllUsesOfValueWith(Val, CastBack);
2866   }
2867 
2868   return DAG.getStore(SN->getChain(), SL, CastVal,
2869                       SN->getBasePtr(), SN->getMemOperand());
2870 }
2871 
2872 // FIXME: This should go in generic DAG combiner with an isTruncateFree check,
2873 // but isTruncateFree is inaccurate for i16 now because of SALU vs. VALU
2874 // issues.
2875 SDValue AMDGPUTargetLowering::performAssertSZExtCombine(SDNode *N,
2876                                                         DAGCombinerInfo &DCI) const {
2877   SelectionDAG &DAG = DCI.DAG;
2878   SDValue N0 = N->getOperand(0);
2879 
2880   // (vt2 (assertzext (truncate vt0:x), vt1)) ->
2881   //     (vt2 (truncate (assertzext vt0:x, vt1)))
2882   if (N0.getOpcode() == ISD::TRUNCATE) {
2883     SDValue N1 = N->getOperand(1);
2884     EVT ExtVT = cast<VTSDNode>(N1)->getVT();
2885     SDLoc SL(N);
2886 
2887     SDValue Src = N0.getOperand(0);
2888     EVT SrcVT = Src.getValueType();
2889     if (SrcVT.bitsGE(ExtVT)) {
2890       SDValue NewInReg = DAG.getNode(N->getOpcode(), SL, SrcVT, Src, N1);
2891       return DAG.getNode(ISD::TRUNCATE, SL, N->getValueType(0), NewInReg);
2892     }
2893   }
2894 
2895   return SDValue();
2896 }
2897 /// Split the 64-bit value \p LHS into two 32-bit components, and perform the
2898 /// binary operation \p Opc to it with the corresponding constant operands.
2899 SDValue AMDGPUTargetLowering::splitBinaryBitConstantOpImpl(
2900   DAGCombinerInfo &DCI, const SDLoc &SL,
2901   unsigned Opc, SDValue LHS,
2902   uint32_t ValLo, uint32_t ValHi) const {
2903   SelectionDAG &DAG = DCI.DAG;
2904   SDValue Lo, Hi;
2905   std::tie(Lo, Hi) = split64BitValue(LHS, DAG);
2906 
2907   SDValue LoRHS = DAG.getConstant(ValLo, SL, MVT::i32);
2908   SDValue HiRHS = DAG.getConstant(ValHi, SL, MVT::i32);
2909 
2910   SDValue LoAnd = DAG.getNode(Opc, SL, MVT::i32, Lo, LoRHS);
2911   SDValue HiAnd = DAG.getNode(Opc, SL, MVT::i32, Hi, HiRHS);
2912 
2913   // Re-visit the ands. It's possible we eliminated one of them and it could
2914   // simplify the vector.
2915   DCI.AddToWorklist(Lo.getNode());
2916   DCI.AddToWorklist(Hi.getNode());
2917 
2918   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
2919   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2920 }
2921 
2922 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
2923                                                 DAGCombinerInfo &DCI) const {
2924   EVT VT = N->getValueType(0);
2925 
2926   ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2927   if (!RHS)
2928     return SDValue();
2929 
2930   SDValue LHS = N->getOperand(0);
2931   unsigned RHSVal = RHS->getZExtValue();
2932   if (!RHSVal)
2933     return LHS;
2934 
2935   SDLoc SL(N);
2936   SelectionDAG &DAG = DCI.DAG;
2937 
2938   switch (LHS->getOpcode()) {
2939   default:
2940     break;
2941   case ISD::ZERO_EXTEND:
2942   case ISD::SIGN_EXTEND:
2943   case ISD::ANY_EXTEND: {
2944     SDValue X = LHS->getOperand(0);
2945 
2946     if (VT == MVT::i32 && RHSVal == 16 && X.getValueType() == MVT::i16 &&
2947         isOperationLegal(ISD::BUILD_VECTOR, MVT::v2i16)) {
2948       // Prefer build_vector as the canonical form if packed types are legal.
2949       // (shl ([asz]ext i16:x), 16 -> build_vector 0, x
2950       SDValue Vec = DAG.getBuildVector(MVT::v2i16, SL,
2951        { DAG.getConstant(0, SL, MVT::i16), LHS->getOperand(0) });
2952       return DAG.getNode(ISD::BITCAST, SL, MVT::i32, Vec);
2953     }
2954 
2955     // shl (ext x) => zext (shl x), if shift does not overflow int
2956     if (VT != MVT::i64)
2957       break;
2958     KnownBits Known;
2959     DAG.computeKnownBits(X, Known);
2960     unsigned LZ = Known.countMinLeadingZeros();
2961     if (LZ < RHSVal)
2962       break;
2963     EVT XVT = X.getValueType();
2964     SDValue Shl = DAG.getNode(ISD::SHL, SL, XVT, X, SDValue(RHS, 0));
2965     return DAG.getZExtOrTrunc(Shl, SL, VT);
2966   }
2967   }
2968 
2969   if (VT != MVT::i64)
2970     return SDValue();
2971 
2972   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
2973 
2974   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
2975   // common case, splitting this into a move and a 32-bit shift is faster and
2976   // the same code size.
2977   if (RHSVal < 32)
2978     return SDValue();
2979 
2980   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
2981 
2982   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
2983   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
2984 
2985   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2986 
2987   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
2988   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2989 }
2990 
2991 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
2992                                                 DAGCombinerInfo &DCI) const {
2993   if (N->getValueType(0) != MVT::i64)
2994     return SDValue();
2995 
2996   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2997   if (!RHS)
2998     return SDValue();
2999 
3000   SelectionDAG &DAG = DCI.DAG;
3001   SDLoc SL(N);
3002   unsigned RHSVal = RHS->getZExtValue();
3003 
3004   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
3005   if (RHSVal == 32) {
3006     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3007     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3008                                    DAG.getConstant(31, SL, MVT::i32));
3009 
3010     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
3011     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3012   }
3013 
3014   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
3015   if (RHSVal == 63) {
3016     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
3017     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
3018                                    DAG.getConstant(31, SL, MVT::i32));
3019     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
3020     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
3021   }
3022 
3023   return SDValue();
3024 }
3025 
3026 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
3027                                                 DAGCombinerInfo &DCI) const {
3028   if (N->getValueType(0) != MVT::i64)
3029     return SDValue();
3030 
3031   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
3032   if (!RHS)
3033     return SDValue();
3034 
3035   unsigned ShiftAmt = RHS->getZExtValue();
3036   if (ShiftAmt < 32)
3037     return SDValue();
3038 
3039   // srl i64:x, C for C >= 32
3040   // =>
3041   //   build_pair (srl hi_32(x), C - 32), 0
3042 
3043   SelectionDAG &DAG = DCI.DAG;
3044   SDLoc SL(N);
3045 
3046   SDValue One = DAG.getConstant(1, SL, MVT::i32);
3047   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
3048 
3049   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, N->getOperand(0));
3050   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32,
3051                            VecOp, One);
3052 
3053   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
3054   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
3055 
3056   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
3057 
3058   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
3059 }
3060 
3061 SDValue AMDGPUTargetLowering::performTruncateCombine(
3062   SDNode *N, DAGCombinerInfo &DCI) const {
3063   SDLoc SL(N);
3064   SelectionDAG &DAG = DCI.DAG;
3065   EVT VT = N->getValueType(0);
3066   SDValue Src = N->getOperand(0);
3067 
3068   // vt1 (truncate (bitcast (build_vector vt0:x, ...))) -> vt1 (bitcast vt0:x)
3069   if (Src.getOpcode() == ISD::BITCAST) {
3070     SDValue Vec = Src.getOperand(0);
3071     if (Vec.getOpcode() == ISD::BUILD_VECTOR) {
3072       SDValue Elt0 = Vec.getOperand(0);
3073       EVT EltVT = Elt0.getValueType();
3074       if (VT.getSizeInBits() <= EltVT.getSizeInBits()) {
3075         if (EltVT.isFloatingPoint()) {
3076           Elt0 = DAG.getNode(ISD::BITCAST, SL,
3077                              EltVT.changeTypeToInteger(), Elt0);
3078         }
3079 
3080         return DAG.getNode(ISD::TRUNCATE, SL, VT, Elt0);
3081       }
3082     }
3083   }
3084 
3085   // Equivalent of above for accessing the high element of a vector as an
3086   // integer operation.
3087   // trunc (srl (bitcast (build_vector x, y))), 16 -> trunc (bitcast y)
3088   if (Src.getOpcode() == ISD::SRL && !VT.isVector()) {
3089     if (auto K = isConstOrConstSplat(Src.getOperand(1))) {
3090       if (2 * K->getZExtValue() == Src.getValueType().getScalarSizeInBits()) {
3091         SDValue BV = stripBitcast(Src.getOperand(0));
3092         if (BV.getOpcode() == ISD::BUILD_VECTOR &&
3093             BV.getValueType().getVectorNumElements() == 2) {
3094           SDValue SrcElt = BV.getOperand(1);
3095           EVT SrcEltVT = SrcElt.getValueType();
3096           if (SrcEltVT.isFloatingPoint()) {
3097             SrcElt = DAG.getNode(ISD::BITCAST, SL,
3098                                  SrcEltVT.changeTypeToInteger(), SrcElt);
3099           }
3100 
3101           return DAG.getNode(ISD::TRUNCATE, SL, VT, SrcElt);
3102         }
3103       }
3104     }
3105   }
3106 
3107   // Partially shrink 64-bit shifts to 32-bit if reduced to 16-bit.
3108   //
3109   // i16 (trunc (srl i64:x, K)), K <= 16 ->
3110   //     i16 (trunc (srl (i32 (trunc x), K)))
3111   if (VT.getScalarSizeInBits() < 32) {
3112     EVT SrcVT = Src.getValueType();
3113     if (SrcVT.getScalarSizeInBits() > 32 &&
3114         (Src.getOpcode() == ISD::SRL ||
3115          Src.getOpcode() == ISD::SRA ||
3116          Src.getOpcode() == ISD::SHL)) {
3117       SDValue Amt = Src.getOperand(1);
3118       KnownBits Known;
3119       DAG.computeKnownBits(Amt, Known);
3120       unsigned Size = VT.getScalarSizeInBits();
3121       if ((Known.isConstant() && Known.getConstant().ule(Size)) ||
3122           (Known.getBitWidth() - Known.countMinLeadingZeros() <= Log2_32(Size))) {
3123         EVT MidVT = VT.isVector() ?
3124           EVT::getVectorVT(*DAG.getContext(), MVT::i32,
3125                            VT.getVectorNumElements()) : MVT::i32;
3126 
3127         EVT NewShiftVT = getShiftAmountTy(MidVT, DAG.getDataLayout());
3128         SDValue Trunc = DAG.getNode(ISD::TRUNCATE, SL, MidVT,
3129                                     Src.getOperand(0));
3130         DCI.AddToWorklist(Trunc.getNode());
3131 
3132         if (Amt.getValueType() != NewShiftVT) {
3133           Amt = DAG.getZExtOrTrunc(Amt, SL, NewShiftVT);
3134           DCI.AddToWorklist(Amt.getNode());
3135         }
3136 
3137         SDValue ShrunkShift = DAG.getNode(Src.getOpcode(), SL, MidVT,
3138                                           Trunc, Amt);
3139         return DAG.getNode(ISD::TRUNCATE, SL, VT, ShrunkShift);
3140       }
3141     }
3142   }
3143 
3144   return SDValue();
3145 }
3146 
3147 // We need to specifically handle i64 mul here to avoid unnecessary conversion
3148 // instructions. If we only match on the legalized i64 mul expansion,
3149 // SimplifyDemandedBits will be unable to remove them because there will be
3150 // multiple uses due to the separate mul + mulh[su].
3151 static SDValue getMul24(SelectionDAG &DAG, const SDLoc &SL,
3152                         SDValue N0, SDValue N1, unsigned Size, bool Signed) {
3153   if (Size <= 32) {
3154     unsigned MulOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3155     return DAG.getNode(MulOpc, SL, MVT::i32, N0, N1);
3156   }
3157 
3158   // Because we want to eliminate extension instructions before the
3159   // operation, we need to create a single user here (i.e. not the separate
3160   // mul_lo + mul_hi) so that SimplifyDemandedBits will deal with it.
3161 
3162   unsigned MulOpc = Signed ? AMDGPUISD::MUL_LOHI_I24 : AMDGPUISD::MUL_LOHI_U24;
3163 
3164   SDValue Mul = DAG.getNode(MulOpc, SL,
3165                             DAG.getVTList(MVT::i32, MVT::i32), N0, N1);
3166 
3167   return DAG.getNode(ISD::BUILD_PAIR, SL, MVT::i64,
3168                      Mul.getValue(0), Mul.getValue(1));
3169 }
3170 
3171 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
3172                                                 DAGCombinerInfo &DCI) const {
3173   EVT VT = N->getValueType(0);
3174 
3175   unsigned Size = VT.getSizeInBits();
3176   if (VT.isVector() || Size > 64)
3177     return SDValue();
3178 
3179   // There are i16 integer mul/mad.
3180   if (Subtarget->has16BitInsts() && VT.getScalarType().bitsLE(MVT::i16))
3181     return SDValue();
3182 
3183   SelectionDAG &DAG = DCI.DAG;
3184   SDLoc DL(N);
3185 
3186   SDValue N0 = N->getOperand(0);
3187   SDValue N1 = N->getOperand(1);
3188 
3189   // SimplifyDemandedBits has the annoying habit of turning useful zero_extends
3190   // in the source into any_extends if the result of the mul is truncated. Since
3191   // we can assume the high bits are whatever we want, use the underlying value
3192   // to avoid the unknown high bits from interfering.
3193   if (N0.getOpcode() == ISD::ANY_EXTEND)
3194     N0 = N0.getOperand(0);
3195 
3196   if (N1.getOpcode() == ISD::ANY_EXTEND)
3197     N1 = N1.getOperand(0);
3198 
3199   SDValue Mul;
3200 
3201   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
3202     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3203     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3204     Mul = getMul24(DAG, DL, N0, N1, Size, false);
3205   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
3206     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3207     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3208     Mul = getMul24(DAG, DL, N0, N1, Size, true);
3209   } else {
3210     return SDValue();
3211   }
3212 
3213   // We need to use sext even for MUL_U24, because MUL_U24 is used
3214   // for signed multiply of 8 and 16-bit types.
3215   return DAG.getSExtOrTrunc(Mul, DL, VT);
3216 }
3217 
3218 SDValue AMDGPUTargetLowering::performMulhsCombine(SDNode *N,
3219                                                   DAGCombinerInfo &DCI) const {
3220   EVT VT = N->getValueType(0);
3221 
3222   if (!Subtarget->hasMulI24() || VT.isVector())
3223     return SDValue();
3224 
3225   SelectionDAG &DAG = DCI.DAG;
3226   SDLoc DL(N);
3227 
3228   SDValue N0 = N->getOperand(0);
3229   SDValue N1 = N->getOperand(1);
3230 
3231   if (!isI24(N0, DAG) || !isI24(N1, DAG))
3232     return SDValue();
3233 
3234   N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
3235   N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
3236 
3237   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_I24, DL, MVT::i32, N0, N1);
3238   DCI.AddToWorklist(Mulhi.getNode());
3239   return DAG.getSExtOrTrunc(Mulhi, DL, VT);
3240 }
3241 
3242 SDValue AMDGPUTargetLowering::performMulhuCombine(SDNode *N,
3243                                                   DAGCombinerInfo &DCI) const {
3244   EVT VT = N->getValueType(0);
3245 
3246   if (!Subtarget->hasMulU24() || VT.isVector() || VT.getSizeInBits() > 32)
3247     return SDValue();
3248 
3249   SelectionDAG &DAG = DCI.DAG;
3250   SDLoc DL(N);
3251 
3252   SDValue N0 = N->getOperand(0);
3253   SDValue N1 = N->getOperand(1);
3254 
3255   if (!isU24(N0, DAG) || !isU24(N1, DAG))
3256     return SDValue();
3257 
3258   N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
3259   N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
3260 
3261   SDValue Mulhi = DAG.getNode(AMDGPUISD::MULHI_U24, DL, MVT::i32, N0, N1);
3262   DCI.AddToWorklist(Mulhi.getNode());
3263   return DAG.getZExtOrTrunc(Mulhi, DL, VT);
3264 }
3265 
3266 SDValue AMDGPUTargetLowering::performMulLoHi24Combine(
3267   SDNode *N, DAGCombinerInfo &DCI) const {
3268   SelectionDAG &DAG = DCI.DAG;
3269 
3270   // Simplify demanded bits before splitting into multiple users.
3271   if (simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI))
3272     return SDValue();
3273 
3274   SDValue N0 = N->getOperand(0);
3275   SDValue N1 = N->getOperand(1);
3276 
3277   bool Signed = (N->getOpcode() == AMDGPUISD::MUL_LOHI_I24);
3278 
3279   unsigned MulLoOpc = Signed ? AMDGPUISD::MUL_I24 : AMDGPUISD::MUL_U24;
3280   unsigned MulHiOpc = Signed ? AMDGPUISD::MULHI_I24 : AMDGPUISD::MULHI_U24;
3281 
3282   SDLoc SL(N);
3283 
3284   SDValue MulLo = DAG.getNode(MulLoOpc, SL, MVT::i32, N0, N1);
3285   SDValue MulHi = DAG.getNode(MulHiOpc, SL, MVT::i32, N0, N1);
3286   return DAG.getMergeValues({ MulLo, MulHi }, SL);
3287 }
3288 
3289 static bool isNegativeOne(SDValue Val) {
3290   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
3291     return C->isAllOnesValue();
3292   return false;
3293 }
3294 
3295 SDValue AMDGPUTargetLowering::getFFBX_U32(SelectionDAG &DAG,
3296                                           SDValue Op,
3297                                           const SDLoc &DL,
3298                                           unsigned Opc) const {
3299   EVT VT = Op.getValueType();
3300   EVT LegalVT = getTypeToTransformTo(*DAG.getContext(), VT);
3301   if (LegalVT != MVT::i32 && (Subtarget->has16BitInsts() &&
3302                               LegalVT != MVT::i16))
3303     return SDValue();
3304 
3305   if (VT != MVT::i32)
3306     Op = DAG.getNode(ISD::ZERO_EXTEND, DL, MVT::i32, Op);
3307 
3308   SDValue FFBX = DAG.getNode(Opc, DL, MVT::i32, Op);
3309   if (VT != MVT::i32)
3310     FFBX = DAG.getNode(ISD::TRUNCATE, DL, VT, FFBX);
3311 
3312   return FFBX;
3313 }
3314 
3315 // The native instructions return -1 on 0 input. Optimize out a select that
3316 // produces -1 on 0.
3317 //
3318 // TODO: If zero is not undef, we could also do this if the output is compared
3319 // against the bitwidth.
3320 //
3321 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
3322 SDValue AMDGPUTargetLowering::performCtlz_CttzCombine(const SDLoc &SL, SDValue Cond,
3323                                                  SDValue LHS, SDValue RHS,
3324                                                  DAGCombinerInfo &DCI) const {
3325   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
3326   if (!CmpRhs || !CmpRhs->isNullValue())
3327     return SDValue();
3328 
3329   SelectionDAG &DAG = DCI.DAG;
3330   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
3331   SDValue CmpLHS = Cond.getOperand(0);
3332 
3333   unsigned Opc = isCttzOpc(RHS.getOpcode()) ? AMDGPUISD::FFBL_B32 :
3334                                            AMDGPUISD::FFBH_U32;
3335 
3336   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
3337   // select (setcc x, 0, eq), -1, (cttz_zero_undef x) -> ffbl_u32 x
3338   if (CCOpcode == ISD::SETEQ &&
3339       (isCtlzOpc(RHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3340       RHS.getOperand(0) == CmpLHS &&
3341       isNegativeOne(LHS)) {
3342     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3343   }
3344 
3345   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
3346   // select (setcc x, 0, ne), (cttz_zero_undef x), -1 -> ffbl_u32 x
3347   if (CCOpcode == ISD::SETNE &&
3348       (isCtlzOpc(LHS.getOpcode()) || isCttzOpc(RHS.getOpcode())) &&
3349       LHS.getOperand(0) == CmpLHS &&
3350       isNegativeOne(RHS)) {
3351     return getFFBX_U32(DAG, CmpLHS, SL, Opc);
3352   }
3353 
3354   return SDValue();
3355 }
3356 
3357 static SDValue distributeOpThroughSelect(TargetLowering::DAGCombinerInfo &DCI,
3358                                          unsigned Op,
3359                                          const SDLoc &SL,
3360                                          SDValue Cond,
3361                                          SDValue N1,
3362                                          SDValue N2) {
3363   SelectionDAG &DAG = DCI.DAG;
3364   EVT VT = N1.getValueType();
3365 
3366   SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT, Cond,
3367                                   N1.getOperand(0), N2.getOperand(0));
3368   DCI.AddToWorklist(NewSelect.getNode());
3369   return DAG.getNode(Op, SL, VT, NewSelect);
3370 }
3371 
3372 // Pull a free FP operation out of a select so it may fold into uses.
3373 //
3374 // select c, (fneg x), (fneg y) -> fneg (select c, x, y)
3375 // select c, (fneg x), k -> fneg (select c, x, (fneg k))
3376 //
3377 // select c, (fabs x), (fabs y) -> fabs (select c, x, y)
3378 // select c, (fabs x), +k -> fabs (select c, x, k)
3379 static SDValue foldFreeOpFromSelect(TargetLowering::DAGCombinerInfo &DCI,
3380                                     SDValue N) {
3381   SelectionDAG &DAG = DCI.DAG;
3382   SDValue Cond = N.getOperand(0);
3383   SDValue LHS = N.getOperand(1);
3384   SDValue RHS = N.getOperand(2);
3385 
3386   EVT VT = N.getValueType();
3387   if ((LHS.getOpcode() == ISD::FABS && RHS.getOpcode() == ISD::FABS) ||
3388       (LHS.getOpcode() == ISD::FNEG && RHS.getOpcode() == ISD::FNEG)) {
3389     return distributeOpThroughSelect(DCI, LHS.getOpcode(),
3390                                      SDLoc(N), Cond, LHS, RHS);
3391   }
3392 
3393   bool Inv = false;
3394   if (RHS.getOpcode() == ISD::FABS || RHS.getOpcode() == ISD::FNEG) {
3395     std::swap(LHS, RHS);
3396     Inv = true;
3397   }
3398 
3399   // TODO: Support vector constants.
3400   ConstantFPSDNode *CRHS = dyn_cast<ConstantFPSDNode>(RHS);
3401   if ((LHS.getOpcode() == ISD::FNEG || LHS.getOpcode() == ISD::FABS) && CRHS) {
3402     SDLoc SL(N);
3403     // If one side is an fneg/fabs and the other is a constant, we can push the
3404     // fneg/fabs down. If it's an fabs, the constant needs to be non-negative.
3405     SDValue NewLHS = LHS.getOperand(0);
3406     SDValue NewRHS = RHS;
3407 
3408     // Careful: if the neg can be folded up, don't try to pull it back down.
3409     bool ShouldFoldNeg = true;
3410 
3411     if (NewLHS.hasOneUse()) {
3412       unsigned Opc = NewLHS.getOpcode();
3413       if (LHS.getOpcode() == ISD::FNEG && fnegFoldsIntoOp(Opc))
3414         ShouldFoldNeg = false;
3415       if (LHS.getOpcode() == ISD::FABS && Opc == ISD::FMUL)
3416         ShouldFoldNeg = false;
3417     }
3418 
3419     if (ShouldFoldNeg) {
3420       if (LHS.getOpcode() == ISD::FNEG)
3421         NewRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3422       else if (CRHS->isNegative())
3423         return SDValue();
3424 
3425       if (Inv)
3426         std::swap(NewLHS, NewRHS);
3427 
3428       SDValue NewSelect = DAG.getNode(ISD::SELECT, SL, VT,
3429                                       Cond, NewLHS, NewRHS);
3430       DCI.AddToWorklist(NewSelect.getNode());
3431       return DAG.getNode(LHS.getOpcode(), SL, VT, NewSelect);
3432     }
3433   }
3434 
3435   return SDValue();
3436 }
3437 
3438 
3439 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
3440                                                    DAGCombinerInfo &DCI) const {
3441   if (SDValue Folded = foldFreeOpFromSelect(DCI, SDValue(N, 0)))
3442     return Folded;
3443 
3444   SDValue Cond = N->getOperand(0);
3445   if (Cond.getOpcode() != ISD::SETCC)
3446     return SDValue();
3447 
3448   EVT VT = N->getValueType(0);
3449   SDValue LHS = Cond.getOperand(0);
3450   SDValue RHS = Cond.getOperand(1);
3451   SDValue CC = Cond.getOperand(2);
3452 
3453   SDValue True = N->getOperand(1);
3454   SDValue False = N->getOperand(2);
3455 
3456   if (Cond.hasOneUse()) { // TODO: Look for multiple select uses.
3457     SelectionDAG &DAG = DCI.DAG;
3458     if ((DAG.isConstantValueOfAnyType(True) ||
3459          DAG.isConstantValueOfAnyType(True)) &&
3460         (!DAG.isConstantValueOfAnyType(False) &&
3461          !DAG.isConstantValueOfAnyType(False))) {
3462       // Swap cmp + select pair to move constant to false input.
3463       // This will allow using VOPC cndmasks more often.
3464       // select (setcc x, y), k, x -> select (setcc y, x) x, x
3465 
3466       SDLoc SL(N);
3467       ISD::CondCode NewCC = getSetCCInverse(cast<CondCodeSDNode>(CC)->get(),
3468                                             LHS.getValueType().isInteger());
3469 
3470       SDValue NewCond = DAG.getSetCC(SL, Cond.getValueType(), LHS, RHS, NewCC);
3471       return DAG.getNode(ISD::SELECT, SL, VT, NewCond, False, True);
3472     }
3473 
3474     if (VT == MVT::f32 && Subtarget->hasFminFmaxLegacy()) {
3475       SDValue MinMax
3476         = combineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
3477       // Revisit this node so we can catch min3/max3/med3 patterns.
3478       //DCI.AddToWorklist(MinMax.getNode());
3479       return MinMax;
3480     }
3481   }
3482 
3483   // There's no reason to not do this if the condition has other uses.
3484   return performCtlz_CttzCombine(SDLoc(N), Cond, True, False, DCI);
3485 }
3486 
3487 static bool isInv2Pi(const APFloat &APF) {
3488   static const APFloat KF16(APFloat::IEEEhalf(), APInt(16, 0x3118));
3489   static const APFloat KF32(APFloat::IEEEsingle(), APInt(32, 0x3e22f983));
3490   static const APFloat KF64(APFloat::IEEEdouble(), APInt(64, 0x3fc45f306dc9c882));
3491 
3492   return APF.bitwiseIsEqual(KF16) ||
3493          APF.bitwiseIsEqual(KF32) ||
3494          APF.bitwiseIsEqual(KF64);
3495 }
3496 
3497 // 0 and 1.0 / (0.5 * pi) do not have inline immmediates, so there is an
3498 // additional cost to negate them.
3499 bool AMDGPUTargetLowering::isConstantCostlierToNegate(SDValue N) const {
3500   if (const ConstantFPSDNode *C = isConstOrConstSplatFP(N)) {
3501     if (C->isZero() && !C->isNegative())
3502       return true;
3503 
3504     if (Subtarget->hasInv2PiInlineImm() && isInv2Pi(C->getValueAPF()))
3505       return true;
3506   }
3507 
3508   return false;
3509 }
3510 
3511 static unsigned inverseMinMax(unsigned Opc) {
3512   switch (Opc) {
3513   case ISD::FMAXNUM:
3514     return ISD::FMINNUM;
3515   case ISD::FMINNUM:
3516     return ISD::FMAXNUM;
3517   case ISD::FMAXNUM_IEEE:
3518     return ISD::FMINNUM_IEEE;
3519   case ISD::FMINNUM_IEEE:
3520     return ISD::FMAXNUM_IEEE;
3521   case AMDGPUISD::FMAX_LEGACY:
3522     return AMDGPUISD::FMIN_LEGACY;
3523   case AMDGPUISD::FMIN_LEGACY:
3524     return  AMDGPUISD::FMAX_LEGACY;
3525   default:
3526     llvm_unreachable("invalid min/max opcode");
3527   }
3528 }
3529 
3530 SDValue AMDGPUTargetLowering::performFNegCombine(SDNode *N,
3531                                                  DAGCombinerInfo &DCI) const {
3532   SelectionDAG &DAG = DCI.DAG;
3533   SDValue N0 = N->getOperand(0);
3534   EVT VT = N->getValueType(0);
3535 
3536   unsigned Opc = N0.getOpcode();
3537 
3538   // If the input has multiple uses and we can either fold the negate down, or
3539   // the other uses cannot, give up. This both prevents unprofitable
3540   // transformations and infinite loops: we won't repeatedly try to fold around
3541   // a negate that has no 'good' form.
3542   if (N0.hasOneUse()) {
3543     // This may be able to fold into the source, but at a code size cost. Don't
3544     // fold if the fold into the user is free.
3545     if (allUsesHaveSourceMods(N, 0))
3546       return SDValue();
3547   } else {
3548     if (fnegFoldsIntoOp(Opc) &&
3549         (allUsesHaveSourceMods(N) || !allUsesHaveSourceMods(N0.getNode())))
3550       return SDValue();
3551   }
3552 
3553   SDLoc SL(N);
3554   switch (Opc) {
3555   case ISD::FADD: {
3556     if (!mayIgnoreSignedZero(N0))
3557       return SDValue();
3558 
3559     // (fneg (fadd x, y)) -> (fadd (fneg x), (fneg y))
3560     SDValue LHS = N0.getOperand(0);
3561     SDValue RHS = N0.getOperand(1);
3562 
3563     if (LHS.getOpcode() != ISD::FNEG)
3564       LHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3565     else
3566       LHS = LHS.getOperand(0);
3567 
3568     if (RHS.getOpcode() != ISD::FNEG)
3569       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3570     else
3571       RHS = RHS.getOperand(0);
3572 
3573     SDValue Res = DAG.getNode(ISD::FADD, SL, VT, LHS, RHS, N0->getFlags());
3574     if (!N0.hasOneUse())
3575       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3576     return Res;
3577   }
3578   case ISD::FMUL:
3579   case AMDGPUISD::FMUL_LEGACY: {
3580     // (fneg (fmul x, y)) -> (fmul x, (fneg y))
3581     // (fneg (fmul_legacy x, y)) -> (fmul_legacy x, (fneg y))
3582     SDValue LHS = N0.getOperand(0);
3583     SDValue RHS = N0.getOperand(1);
3584 
3585     if (LHS.getOpcode() == ISD::FNEG)
3586       LHS = LHS.getOperand(0);
3587     else if (RHS.getOpcode() == ISD::FNEG)
3588       RHS = RHS.getOperand(0);
3589     else
3590       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3591 
3592     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, RHS, N0->getFlags());
3593     if (!N0.hasOneUse())
3594       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3595     return Res;
3596   }
3597   case ISD::FMA:
3598   case ISD::FMAD: {
3599     if (!mayIgnoreSignedZero(N0))
3600       return SDValue();
3601 
3602     // (fneg (fma x, y, z)) -> (fma x, (fneg y), (fneg z))
3603     SDValue LHS = N0.getOperand(0);
3604     SDValue MHS = N0.getOperand(1);
3605     SDValue RHS = N0.getOperand(2);
3606 
3607     if (LHS.getOpcode() == ISD::FNEG)
3608       LHS = LHS.getOperand(0);
3609     else if (MHS.getOpcode() == ISD::FNEG)
3610       MHS = MHS.getOperand(0);
3611     else
3612       MHS = DAG.getNode(ISD::FNEG, SL, VT, MHS);
3613 
3614     if (RHS.getOpcode() != ISD::FNEG)
3615       RHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3616     else
3617       RHS = RHS.getOperand(0);
3618 
3619     SDValue Res = DAG.getNode(Opc, SL, VT, LHS, MHS, RHS);
3620     if (!N0.hasOneUse())
3621       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3622     return Res;
3623   }
3624   case ISD::FMAXNUM:
3625   case ISD::FMINNUM:
3626   case ISD::FMAXNUM_IEEE:
3627   case ISD::FMINNUM_IEEE:
3628   case AMDGPUISD::FMAX_LEGACY:
3629   case AMDGPUISD::FMIN_LEGACY: {
3630     // fneg (fmaxnum x, y) -> fminnum (fneg x), (fneg y)
3631     // fneg (fminnum x, y) -> fmaxnum (fneg x), (fneg y)
3632     // fneg (fmax_legacy x, y) -> fmin_legacy (fneg x), (fneg y)
3633     // fneg (fmin_legacy x, y) -> fmax_legacy (fneg x), (fneg y)
3634 
3635     SDValue LHS = N0.getOperand(0);
3636     SDValue RHS = N0.getOperand(1);
3637 
3638     // 0 doesn't have a negated inline immediate.
3639     // TODO: This constant check should be generalized to other operations.
3640     if (isConstantCostlierToNegate(RHS))
3641       return SDValue();
3642 
3643     SDValue NegLHS = DAG.getNode(ISD::FNEG, SL, VT, LHS);
3644     SDValue NegRHS = DAG.getNode(ISD::FNEG, SL, VT, RHS);
3645     unsigned Opposite = inverseMinMax(Opc);
3646 
3647     SDValue Res = DAG.getNode(Opposite, SL, VT, NegLHS, NegRHS, N0->getFlags());
3648     if (!N0.hasOneUse())
3649       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3650     return Res;
3651   }
3652   case AMDGPUISD::FMED3: {
3653     SDValue Ops[3];
3654     for (unsigned I = 0; I < 3; ++I)
3655       Ops[I] = DAG.getNode(ISD::FNEG, SL, VT, N0->getOperand(I), N0->getFlags());
3656 
3657     SDValue Res = DAG.getNode(AMDGPUISD::FMED3, SL, VT, Ops, N0->getFlags());
3658     if (!N0.hasOneUse())
3659       DAG.ReplaceAllUsesWith(N0, DAG.getNode(ISD::FNEG, SL, VT, Res));
3660     return Res;
3661   }
3662   case ISD::FP_EXTEND:
3663   case ISD::FTRUNC:
3664   case ISD::FRINT:
3665   case ISD::FNEARBYINT: // XXX - Should fround be handled?
3666   case ISD::FSIN:
3667   case ISD::FCANONICALIZE:
3668   case AMDGPUISD::RCP:
3669   case AMDGPUISD::RCP_LEGACY:
3670   case AMDGPUISD::RCP_IFLAG:
3671   case AMDGPUISD::SIN_HW: {
3672     SDValue CvtSrc = N0.getOperand(0);
3673     if (CvtSrc.getOpcode() == ISD::FNEG) {
3674       // (fneg (fp_extend (fneg x))) -> (fp_extend x)
3675       // (fneg (rcp (fneg x))) -> (rcp x)
3676       return DAG.getNode(Opc, SL, VT, CvtSrc.getOperand(0));
3677     }
3678 
3679     if (!N0.hasOneUse())
3680       return SDValue();
3681 
3682     // (fneg (fp_extend x)) -> (fp_extend (fneg x))
3683     // (fneg (rcp x)) -> (rcp (fneg x))
3684     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3685     return DAG.getNode(Opc, SL, VT, Neg, N0->getFlags());
3686   }
3687   case ISD::FP_ROUND: {
3688     SDValue CvtSrc = N0.getOperand(0);
3689 
3690     if (CvtSrc.getOpcode() == ISD::FNEG) {
3691       // (fneg (fp_round (fneg x))) -> (fp_round x)
3692       return DAG.getNode(ISD::FP_ROUND, SL, VT,
3693                          CvtSrc.getOperand(0), N0.getOperand(1));
3694     }
3695 
3696     if (!N0.hasOneUse())
3697       return SDValue();
3698 
3699     // (fneg (fp_round x)) -> (fp_round (fneg x))
3700     SDValue Neg = DAG.getNode(ISD::FNEG, SL, CvtSrc.getValueType(), CvtSrc);
3701     return DAG.getNode(ISD::FP_ROUND, SL, VT, Neg, N0.getOperand(1));
3702   }
3703   case ISD::FP16_TO_FP: {
3704     // v_cvt_f32_f16 supports source modifiers on pre-VI targets without legal
3705     // f16, but legalization of f16 fneg ends up pulling it out of the source.
3706     // Put the fneg back as a legal source operation that can be matched later.
3707     SDLoc SL(N);
3708 
3709     SDValue Src = N0.getOperand(0);
3710     EVT SrcVT = Src.getValueType();
3711 
3712     // fneg (fp16_to_fp x) -> fp16_to_fp (xor x, 0x8000)
3713     SDValue IntFNeg = DAG.getNode(ISD::XOR, SL, SrcVT, Src,
3714                                   DAG.getConstant(0x8000, SL, SrcVT));
3715     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFNeg);
3716   }
3717   default:
3718     return SDValue();
3719   }
3720 }
3721 
3722 SDValue AMDGPUTargetLowering::performFAbsCombine(SDNode *N,
3723                                                  DAGCombinerInfo &DCI) const {
3724   SelectionDAG &DAG = DCI.DAG;
3725   SDValue N0 = N->getOperand(0);
3726 
3727   if (!N0.hasOneUse())
3728     return SDValue();
3729 
3730   switch (N0.getOpcode()) {
3731   case ISD::FP16_TO_FP: {
3732     assert(!Subtarget->has16BitInsts() && "should only see if f16 is illegal");
3733     SDLoc SL(N);
3734     SDValue Src = N0.getOperand(0);
3735     EVT SrcVT = Src.getValueType();
3736 
3737     // fabs (fp16_to_fp x) -> fp16_to_fp (and x, 0x7fff)
3738     SDValue IntFAbs = DAG.getNode(ISD::AND, SL, SrcVT, Src,
3739                                   DAG.getConstant(0x7fff, SL, SrcVT));
3740     return DAG.getNode(ISD::FP16_TO_FP, SL, N->getValueType(0), IntFAbs);
3741   }
3742   default:
3743     return SDValue();
3744   }
3745 }
3746 
3747 SDValue AMDGPUTargetLowering::performRcpCombine(SDNode *N,
3748                                                 DAGCombinerInfo &DCI) const {
3749   const auto *CFP = dyn_cast<ConstantFPSDNode>(N->getOperand(0));
3750   if (!CFP)
3751     return SDValue();
3752 
3753   // XXX - Should this flush denormals?
3754   const APFloat &Val = CFP->getValueAPF();
3755   APFloat One(Val.getSemantics(), "1.0");
3756   return DCI.DAG.getConstantFP(One / Val, SDLoc(N), N->getValueType(0));
3757 }
3758 
3759 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
3760                                                 DAGCombinerInfo &DCI) const {
3761   SelectionDAG &DAG = DCI.DAG;
3762   SDLoc DL(N);
3763 
3764   switch(N->getOpcode()) {
3765   default:
3766     break;
3767   case ISD::BITCAST: {
3768     EVT DestVT = N->getValueType(0);
3769 
3770     // Push casts through vector builds. This helps avoid emitting a large
3771     // number of copies when materializing floating point vector constants.
3772     //
3773     // vNt1 bitcast (vNt0 (build_vector t0:x, t0:y)) =>
3774     //   vnt1 = build_vector (t1 (bitcast t0:x)), (t1 (bitcast t0:y))
3775     if (DestVT.isVector()) {
3776       SDValue Src = N->getOperand(0);
3777       if (Src.getOpcode() == ISD::BUILD_VECTOR) {
3778         EVT SrcVT = Src.getValueType();
3779         unsigned NElts = DestVT.getVectorNumElements();
3780 
3781         if (SrcVT.getVectorNumElements() == NElts) {
3782           EVT DestEltVT = DestVT.getVectorElementType();
3783 
3784           SmallVector<SDValue, 8> CastedElts;
3785           SDLoc SL(N);
3786           for (unsigned I = 0, E = SrcVT.getVectorNumElements(); I != E; ++I) {
3787             SDValue Elt = Src.getOperand(I);
3788             CastedElts.push_back(DAG.getNode(ISD::BITCAST, DL, DestEltVT, Elt));
3789           }
3790 
3791           return DAG.getBuildVector(DestVT, SL, CastedElts);
3792         }
3793       }
3794     }
3795 
3796     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
3797       break;
3798 
3799     // Fold bitcasts of constants.
3800     //
3801     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
3802     // TODO: Generalize and move to DAGCombiner
3803     SDValue Src = N->getOperand(0);
3804     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
3805       if (Src.getValueType() == MVT::i64) {
3806         SDLoc SL(N);
3807         uint64_t CVal = C->getZExtValue();
3808         return DAG.getNode(ISD::BUILD_VECTOR, SL, DestVT,
3809                            DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3810                            DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3811       }
3812     }
3813 
3814     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
3815       const APInt &Val = C->getValueAPF().bitcastToAPInt();
3816       SDLoc SL(N);
3817       uint64_t CVal = Val.getZExtValue();
3818       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
3819                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
3820                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
3821 
3822       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
3823     }
3824 
3825     break;
3826   }
3827   case ISD::SHL: {
3828     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3829       break;
3830 
3831     return performShlCombine(N, DCI);
3832   }
3833   case ISD::SRL: {
3834     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3835       break;
3836 
3837     return performSrlCombine(N, DCI);
3838   }
3839   case ISD::SRA: {
3840     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
3841       break;
3842 
3843     return performSraCombine(N, DCI);
3844   }
3845   case ISD::TRUNCATE:
3846     return performTruncateCombine(N, DCI);
3847   case ISD::MUL:
3848     return performMulCombine(N, DCI);
3849   case ISD::MULHS:
3850     return performMulhsCombine(N, DCI);
3851   case ISD::MULHU:
3852     return performMulhuCombine(N, DCI);
3853   case AMDGPUISD::MUL_I24:
3854   case AMDGPUISD::MUL_U24:
3855   case AMDGPUISD::MULHI_I24:
3856   case AMDGPUISD::MULHI_U24: {
3857     // If the first call to simplify is successfull, then N may end up being
3858     // deleted, so we shouldn't call simplifyI24 again.
3859     simplifyI24(N, 0, DCI) || simplifyI24(N, 1, DCI);
3860     return SDValue();
3861   }
3862   case AMDGPUISD::MUL_LOHI_I24:
3863   case AMDGPUISD::MUL_LOHI_U24:
3864     return performMulLoHi24Combine(N, DCI);
3865   case ISD::SELECT:
3866     return performSelectCombine(N, DCI);
3867   case ISD::FNEG:
3868     return performFNegCombine(N, DCI);
3869   case ISD::FABS:
3870     return performFAbsCombine(N, DCI);
3871   case AMDGPUISD::BFE_I32:
3872   case AMDGPUISD::BFE_U32: {
3873     assert(!N->getValueType(0).isVector() &&
3874            "Vector handling of BFE not implemented");
3875     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
3876     if (!Width)
3877       break;
3878 
3879     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
3880     if (WidthVal == 0)
3881       return DAG.getConstant(0, DL, MVT::i32);
3882 
3883     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
3884     if (!Offset)
3885       break;
3886 
3887     SDValue BitsFrom = N->getOperand(0);
3888     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
3889 
3890     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
3891 
3892     if (OffsetVal == 0) {
3893       // This is already sign / zero extended, so try to fold away extra BFEs.
3894       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
3895 
3896       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
3897       if (OpSignBits >= SignBits)
3898         return BitsFrom;
3899 
3900       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
3901       if (Signed) {
3902         // This is a sign_extend_inreg. Replace it to take advantage of existing
3903         // DAG Combines. If not eliminated, we will match back to BFE during
3904         // selection.
3905 
3906         // TODO: The sext_inreg of extended types ends, although we can could
3907         // handle them in a single BFE.
3908         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
3909                            DAG.getValueType(SmallVT));
3910       }
3911 
3912       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
3913     }
3914 
3915     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
3916       if (Signed) {
3917         return constantFoldBFE<int32_t>(DAG,
3918                                         CVal->getSExtValue(),
3919                                         OffsetVal,
3920                                         WidthVal,
3921                                         DL);
3922       }
3923 
3924       return constantFoldBFE<uint32_t>(DAG,
3925                                        CVal->getZExtValue(),
3926                                        OffsetVal,
3927                                        WidthVal,
3928                                        DL);
3929     }
3930 
3931     if ((OffsetVal + WidthVal) >= 32 &&
3932         !(Subtarget->hasSDWA() && OffsetVal == 16 && WidthVal == 16)) {
3933       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
3934       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
3935                          BitsFrom, ShiftVal);
3936     }
3937 
3938     if (BitsFrom.hasOneUse()) {
3939       APInt Demanded = APInt::getBitsSet(32,
3940                                          OffsetVal,
3941                                          OffsetVal + WidthVal);
3942 
3943       KnownBits Known;
3944       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
3945                                             !DCI.isBeforeLegalizeOps());
3946       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
3947       if (TLI.ShrinkDemandedConstant(BitsFrom, Demanded, TLO) ||
3948           TLI.SimplifyDemandedBits(BitsFrom, Demanded, Known, TLO)) {
3949         DCI.CommitTargetLoweringOpt(TLO);
3950       }
3951     }
3952 
3953     break;
3954   }
3955   case ISD::LOAD:
3956     return performLoadCombine(N, DCI);
3957   case ISD::STORE:
3958     return performStoreCombine(N, DCI);
3959   case AMDGPUISD::RCP:
3960   case AMDGPUISD::RCP_IFLAG:
3961     return performRcpCombine(N, DCI);
3962   case ISD::AssertZext:
3963   case ISD::AssertSext:
3964     return performAssertSZExtCombine(N, DCI);
3965   }
3966   return SDValue();
3967 }
3968 
3969 //===----------------------------------------------------------------------===//
3970 // Helper functions
3971 //===----------------------------------------------------------------------===//
3972 
3973 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
3974                                                    const TargetRegisterClass *RC,
3975                                                    unsigned Reg, EVT VT,
3976                                                    const SDLoc &SL,
3977                                                    bool RawReg) const {
3978   MachineFunction &MF = DAG.getMachineFunction();
3979   MachineRegisterInfo &MRI = MF.getRegInfo();
3980   unsigned VReg;
3981 
3982   if (!MRI.isLiveIn(Reg)) {
3983     VReg = MRI.createVirtualRegister(RC);
3984     MRI.addLiveIn(Reg, VReg);
3985   } else {
3986     VReg = MRI.getLiveInVirtReg(Reg);
3987   }
3988 
3989   if (RawReg)
3990     return DAG.getRegister(VReg, VT);
3991 
3992   return DAG.getCopyFromReg(DAG.getEntryNode(), SL, VReg, VT);
3993 }
3994 
3995 SDValue AMDGPUTargetLowering::loadStackInputValue(SelectionDAG &DAG,
3996                                                   EVT VT,
3997                                                   const SDLoc &SL,
3998                                                   int64_t Offset) const {
3999   MachineFunction &MF = DAG.getMachineFunction();
4000   MachineFrameInfo &MFI = MF.getFrameInfo();
4001 
4002   int FI = MFI.CreateFixedObject(VT.getStoreSize(), Offset, true);
4003   auto SrcPtrInfo = MachinePointerInfo::getStack(MF, Offset);
4004   SDValue Ptr = DAG.getFrameIndex(FI, MVT::i32);
4005 
4006   return DAG.getLoad(VT, SL, DAG.getEntryNode(), Ptr, SrcPtrInfo, 4,
4007                      MachineMemOperand::MODereferenceable |
4008                      MachineMemOperand::MOInvariant);
4009 }
4010 
4011 SDValue AMDGPUTargetLowering::storeStackInputValue(SelectionDAG &DAG,
4012                                                    const SDLoc &SL,
4013                                                    SDValue Chain,
4014                                                    SDValue ArgVal,
4015                                                    int64_t Offset) const {
4016   MachineFunction &MF = DAG.getMachineFunction();
4017   MachinePointerInfo DstInfo = MachinePointerInfo::getStack(MF, Offset);
4018 
4019   SDValue Ptr = DAG.getConstant(Offset, SL, MVT::i32);
4020   SDValue Store = DAG.getStore(Chain, SL, ArgVal, Ptr, DstInfo, 4,
4021                                MachineMemOperand::MODereferenceable);
4022   return Store;
4023 }
4024 
4025 SDValue AMDGPUTargetLowering::loadInputValue(SelectionDAG &DAG,
4026                                              const TargetRegisterClass *RC,
4027                                              EVT VT, const SDLoc &SL,
4028                                              const ArgDescriptor &Arg) const {
4029   assert(Arg && "Attempting to load missing argument");
4030 
4031   if (Arg.isRegister())
4032     return CreateLiveInRegister(DAG, RC, Arg.getRegister(), VT, SL);
4033   return loadStackInputValue(DAG, VT, SL, Arg.getStackOffset());
4034 }
4035 
4036 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
4037     const MachineFunction &MF, const ImplicitParameter Param) const {
4038   const AMDGPUMachineFunction *MFI = MF.getInfo<AMDGPUMachineFunction>();
4039   const AMDGPUSubtarget &ST =
4040       AMDGPUSubtarget::get(getTargetMachine(), MF.getFunction());
4041   unsigned ExplicitArgOffset = ST.getExplicitKernelArgOffset(MF.getFunction());
4042   unsigned Alignment = ST.getAlignmentForImplicitArgPtr();
4043   uint64_t ArgOffset = alignTo(MFI->getExplicitKernArgSize(), Alignment) +
4044                        ExplicitArgOffset;
4045   switch (Param) {
4046   case GRID_DIM:
4047     return ArgOffset;
4048   case GRID_OFFSET:
4049     return ArgOffset + 4;
4050   }
4051   llvm_unreachable("unexpected implicit parameter type");
4052 }
4053 
4054 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
4055 
4056 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
4057   switch ((AMDGPUISD::NodeType)Opcode) {
4058   case AMDGPUISD::FIRST_NUMBER: break;
4059   // AMDIL DAG nodes
4060   NODE_NAME_CASE(UMUL);
4061   NODE_NAME_CASE(BRANCH_COND);
4062 
4063   // AMDGPU DAG nodes
4064   NODE_NAME_CASE(IF)
4065   NODE_NAME_CASE(ELSE)
4066   NODE_NAME_CASE(LOOP)
4067   NODE_NAME_CASE(CALL)
4068   NODE_NAME_CASE(TC_RETURN)
4069   NODE_NAME_CASE(TRAP)
4070   NODE_NAME_CASE(RET_FLAG)
4071   NODE_NAME_CASE(RETURN_TO_EPILOG)
4072   NODE_NAME_CASE(ENDPGM)
4073   NODE_NAME_CASE(DWORDADDR)
4074   NODE_NAME_CASE(FRACT)
4075   NODE_NAME_CASE(SETCC)
4076   NODE_NAME_CASE(SETREG)
4077   NODE_NAME_CASE(FMA_W_CHAIN)
4078   NODE_NAME_CASE(FMUL_W_CHAIN)
4079   NODE_NAME_CASE(CLAMP)
4080   NODE_NAME_CASE(COS_HW)
4081   NODE_NAME_CASE(SIN_HW)
4082   NODE_NAME_CASE(FMAX_LEGACY)
4083   NODE_NAME_CASE(FMIN_LEGACY)
4084   NODE_NAME_CASE(FMAX3)
4085   NODE_NAME_CASE(SMAX3)
4086   NODE_NAME_CASE(UMAX3)
4087   NODE_NAME_CASE(FMIN3)
4088   NODE_NAME_CASE(SMIN3)
4089   NODE_NAME_CASE(UMIN3)
4090   NODE_NAME_CASE(FMED3)
4091   NODE_NAME_CASE(SMED3)
4092   NODE_NAME_CASE(UMED3)
4093   NODE_NAME_CASE(FDOT2)
4094   NODE_NAME_CASE(URECIP)
4095   NODE_NAME_CASE(DIV_SCALE)
4096   NODE_NAME_CASE(DIV_FMAS)
4097   NODE_NAME_CASE(DIV_FIXUP)
4098   NODE_NAME_CASE(FMAD_FTZ)
4099   NODE_NAME_CASE(TRIG_PREOP)
4100   NODE_NAME_CASE(RCP)
4101   NODE_NAME_CASE(RSQ)
4102   NODE_NAME_CASE(RCP_LEGACY)
4103   NODE_NAME_CASE(RSQ_LEGACY)
4104   NODE_NAME_CASE(RCP_IFLAG)
4105   NODE_NAME_CASE(FMUL_LEGACY)
4106   NODE_NAME_CASE(RSQ_CLAMP)
4107   NODE_NAME_CASE(LDEXP)
4108   NODE_NAME_CASE(FP_CLASS)
4109   NODE_NAME_CASE(DOT4)
4110   NODE_NAME_CASE(CARRY)
4111   NODE_NAME_CASE(BORROW)
4112   NODE_NAME_CASE(BFE_U32)
4113   NODE_NAME_CASE(BFE_I32)
4114   NODE_NAME_CASE(BFI)
4115   NODE_NAME_CASE(BFM)
4116   NODE_NAME_CASE(FFBH_U32)
4117   NODE_NAME_CASE(FFBH_I32)
4118   NODE_NAME_CASE(FFBL_B32)
4119   NODE_NAME_CASE(MUL_U24)
4120   NODE_NAME_CASE(MUL_I24)
4121   NODE_NAME_CASE(MULHI_U24)
4122   NODE_NAME_CASE(MULHI_I24)
4123   NODE_NAME_CASE(MUL_LOHI_U24)
4124   NODE_NAME_CASE(MUL_LOHI_I24)
4125   NODE_NAME_CASE(MAD_U24)
4126   NODE_NAME_CASE(MAD_I24)
4127   NODE_NAME_CASE(MAD_I64_I32)
4128   NODE_NAME_CASE(MAD_U64_U32)
4129   NODE_NAME_CASE(PERM)
4130   NODE_NAME_CASE(TEXTURE_FETCH)
4131   NODE_NAME_CASE(EXPORT)
4132   NODE_NAME_CASE(EXPORT_DONE)
4133   NODE_NAME_CASE(R600_EXPORT)
4134   NODE_NAME_CASE(CONST_ADDRESS)
4135   NODE_NAME_CASE(REGISTER_LOAD)
4136   NODE_NAME_CASE(REGISTER_STORE)
4137   NODE_NAME_CASE(SAMPLE)
4138   NODE_NAME_CASE(SAMPLEB)
4139   NODE_NAME_CASE(SAMPLED)
4140   NODE_NAME_CASE(SAMPLEL)
4141   NODE_NAME_CASE(CVT_F32_UBYTE0)
4142   NODE_NAME_CASE(CVT_F32_UBYTE1)
4143   NODE_NAME_CASE(CVT_F32_UBYTE2)
4144   NODE_NAME_CASE(CVT_F32_UBYTE3)
4145   NODE_NAME_CASE(CVT_PKRTZ_F16_F32)
4146   NODE_NAME_CASE(CVT_PKNORM_I16_F32)
4147   NODE_NAME_CASE(CVT_PKNORM_U16_F32)
4148   NODE_NAME_CASE(CVT_PK_I16_I32)
4149   NODE_NAME_CASE(CVT_PK_U16_U32)
4150   NODE_NAME_CASE(FP_TO_FP16)
4151   NODE_NAME_CASE(FP16_ZEXT)
4152   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
4153   NODE_NAME_CASE(CONST_DATA_PTR)
4154   NODE_NAME_CASE(PC_ADD_REL_OFFSET)
4155   NODE_NAME_CASE(KILL)
4156   NODE_NAME_CASE(DUMMY_CHAIN)
4157   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
4158   NODE_NAME_CASE(INIT_EXEC)
4159   NODE_NAME_CASE(INIT_EXEC_FROM_INPUT)
4160   NODE_NAME_CASE(SENDMSG)
4161   NODE_NAME_CASE(SENDMSGHALT)
4162   NODE_NAME_CASE(INTERP_MOV)
4163   NODE_NAME_CASE(INTERP_P1)
4164   NODE_NAME_CASE(INTERP_P2)
4165   NODE_NAME_CASE(STORE_MSKOR)
4166   NODE_NAME_CASE(LOAD_CONSTANT)
4167   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
4168   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_X3)
4169   NODE_NAME_CASE(TBUFFER_STORE_FORMAT_D16)
4170   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT)
4171   NODE_NAME_CASE(TBUFFER_LOAD_FORMAT_D16)
4172   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
4173   NODE_NAME_CASE(ATOMIC_INC)
4174   NODE_NAME_CASE(ATOMIC_DEC)
4175   NODE_NAME_CASE(ATOMIC_LOAD_FADD)
4176   NODE_NAME_CASE(ATOMIC_LOAD_FMIN)
4177   NODE_NAME_CASE(ATOMIC_LOAD_FMAX)
4178   NODE_NAME_CASE(BUFFER_LOAD)
4179   NODE_NAME_CASE(BUFFER_LOAD_FORMAT)
4180   NODE_NAME_CASE(BUFFER_LOAD_FORMAT_D16)
4181   NODE_NAME_CASE(SBUFFER_LOAD)
4182   NODE_NAME_CASE(BUFFER_STORE)
4183   NODE_NAME_CASE(BUFFER_STORE_FORMAT)
4184   NODE_NAME_CASE(BUFFER_STORE_FORMAT_D16)
4185   NODE_NAME_CASE(BUFFER_ATOMIC_SWAP)
4186   NODE_NAME_CASE(BUFFER_ATOMIC_ADD)
4187   NODE_NAME_CASE(BUFFER_ATOMIC_SUB)
4188   NODE_NAME_CASE(BUFFER_ATOMIC_SMIN)
4189   NODE_NAME_CASE(BUFFER_ATOMIC_UMIN)
4190   NODE_NAME_CASE(BUFFER_ATOMIC_SMAX)
4191   NODE_NAME_CASE(BUFFER_ATOMIC_UMAX)
4192   NODE_NAME_CASE(BUFFER_ATOMIC_AND)
4193   NODE_NAME_CASE(BUFFER_ATOMIC_OR)
4194   NODE_NAME_CASE(BUFFER_ATOMIC_XOR)
4195   NODE_NAME_CASE(BUFFER_ATOMIC_CMPSWAP)
4196 
4197   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
4198   }
4199   return nullptr;
4200 }
4201 
4202 SDValue AMDGPUTargetLowering::getSqrtEstimate(SDValue Operand,
4203                                               SelectionDAG &DAG, int Enabled,
4204                                               int &RefinementSteps,
4205                                               bool &UseOneConstNR,
4206                                               bool Reciprocal) const {
4207   EVT VT = Operand.getValueType();
4208 
4209   if (VT == MVT::f32) {
4210     RefinementSteps = 0;
4211     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
4212   }
4213 
4214   // TODO: There is also f64 rsq instruction, but the documentation is less
4215   // clear on its precision.
4216 
4217   return SDValue();
4218 }
4219 
4220 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
4221                                                SelectionDAG &DAG, int Enabled,
4222                                                int &RefinementSteps) const {
4223   EVT VT = Operand.getValueType();
4224 
4225   if (VT == MVT::f32) {
4226     // Reciprocal, < 1 ulp error.
4227     //
4228     // This reciprocal approximation converges to < 0.5 ulp error with one
4229     // newton rhapson performed with two fused multiple adds (FMAs).
4230 
4231     RefinementSteps = 0;
4232     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
4233   }
4234 
4235   // TODO: There is also f64 rcp instruction, but the documentation is less
4236   // clear on its precision.
4237 
4238   return SDValue();
4239 }
4240 
4241 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
4242     const SDValue Op, KnownBits &Known,
4243     const APInt &DemandedElts, const SelectionDAG &DAG, unsigned Depth) const {
4244 
4245   Known.resetAll(); // Don't know anything.
4246 
4247   unsigned Opc = Op.getOpcode();
4248 
4249   switch (Opc) {
4250   default:
4251     break;
4252   case AMDGPUISD::CARRY:
4253   case AMDGPUISD::BORROW: {
4254     Known.Zero = APInt::getHighBitsSet(32, 31);
4255     break;
4256   }
4257 
4258   case AMDGPUISD::BFE_I32:
4259   case AMDGPUISD::BFE_U32: {
4260     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4261     if (!CWidth)
4262       return;
4263 
4264     uint32_t Width = CWidth->getZExtValue() & 0x1f;
4265 
4266     if (Opc == AMDGPUISD::BFE_U32)
4267       Known.Zero = APInt::getHighBitsSet(32, 32 - Width);
4268 
4269     break;
4270   }
4271   case AMDGPUISD::FP_TO_FP16:
4272   case AMDGPUISD::FP16_ZEXT: {
4273     unsigned BitWidth = Known.getBitWidth();
4274 
4275     // High bits are zero.
4276     Known.Zero = APInt::getHighBitsSet(BitWidth, BitWidth - 16);
4277     break;
4278   }
4279   case AMDGPUISD::MUL_U24:
4280   case AMDGPUISD::MUL_I24: {
4281     KnownBits LHSKnown, RHSKnown;
4282     DAG.computeKnownBits(Op.getOperand(0), LHSKnown, Depth + 1);
4283     DAG.computeKnownBits(Op.getOperand(1), RHSKnown, Depth + 1);
4284 
4285     unsigned TrailZ = LHSKnown.countMinTrailingZeros() +
4286                       RHSKnown.countMinTrailingZeros();
4287     Known.Zero.setLowBits(std::min(TrailZ, 32u));
4288 
4289     unsigned LHSValBits = 32 - std::max(LHSKnown.countMinSignBits(), 8u);
4290     unsigned RHSValBits = 32 - std::max(RHSKnown.countMinSignBits(), 8u);
4291     unsigned MaxValBits = std::min(LHSValBits + RHSValBits, 32u);
4292     if (MaxValBits >= 32)
4293       break;
4294     bool Negative = false;
4295     if (Opc == AMDGPUISD::MUL_I24) {
4296       bool LHSNegative = !!(LHSKnown.One  & (1 << 23));
4297       bool LHSPositive = !!(LHSKnown.Zero & (1 << 23));
4298       bool RHSNegative = !!(RHSKnown.One  & (1 << 23));
4299       bool RHSPositive = !!(RHSKnown.Zero & (1 << 23));
4300       if ((!LHSNegative && !LHSPositive) || (!RHSNegative && !RHSPositive))
4301         break;
4302       Negative = (LHSNegative && RHSPositive) || (LHSPositive && RHSNegative);
4303     }
4304     if (Negative)
4305       Known.One.setHighBits(32 - MaxValBits);
4306     else
4307       Known.Zero.setHighBits(32 - MaxValBits);
4308     break;
4309   }
4310   case AMDGPUISD::PERM: {
4311     ConstantSDNode *CMask = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4312     if (!CMask)
4313       return;
4314 
4315     KnownBits LHSKnown, RHSKnown;
4316     DAG.computeKnownBits(Op.getOperand(0), LHSKnown, Depth + 1);
4317     DAG.computeKnownBits(Op.getOperand(1), RHSKnown, Depth + 1);
4318     unsigned Sel = CMask->getZExtValue();
4319 
4320     for (unsigned I = 0; I < 32; I += 8) {
4321       unsigned SelBits = Sel & 0xff;
4322       if (SelBits < 4) {
4323         SelBits *= 8;
4324         Known.One |= ((RHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4325         Known.Zero |= ((RHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4326       } else if (SelBits < 7) {
4327         SelBits = (SelBits & 3) * 8;
4328         Known.One |= ((LHSKnown.One.getZExtValue() >> SelBits) & 0xff) << I;
4329         Known.Zero |= ((LHSKnown.Zero.getZExtValue() >> SelBits) & 0xff) << I;
4330       } else if (SelBits == 0x0c) {
4331         Known.Zero |= 0xff << I;
4332       } else if (SelBits > 0x0c) {
4333         Known.One |= 0xff << I;
4334       }
4335       Sel >>= 8;
4336     }
4337     break;
4338   }
4339   case ISD::INTRINSIC_WO_CHAIN: {
4340     unsigned IID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4341     switch (IID) {
4342     case Intrinsic::amdgcn_mbcnt_lo:
4343     case Intrinsic::amdgcn_mbcnt_hi: {
4344       const GCNSubtarget &ST =
4345           DAG.getMachineFunction().getSubtarget<GCNSubtarget>();
4346       // These return at most the wavefront size - 1.
4347       unsigned Size = Op.getValueType().getSizeInBits();
4348       Known.Zero.setHighBits(Size - ST.getWavefrontSizeLog2());
4349       break;
4350     }
4351     default:
4352       break;
4353     }
4354   }
4355   }
4356 }
4357 
4358 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
4359     SDValue Op, const APInt &DemandedElts, const SelectionDAG &DAG,
4360     unsigned Depth) const {
4361   switch (Op.getOpcode()) {
4362   case AMDGPUISD::BFE_I32: {
4363     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4364     if (!Width)
4365       return 1;
4366 
4367     unsigned SignBits = 32 - Width->getZExtValue() + 1;
4368     if (!isNullConstant(Op.getOperand(1)))
4369       return SignBits;
4370 
4371     // TODO: Could probably figure something out with non-0 offsets.
4372     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
4373     return std::max(SignBits, Op0SignBits);
4374   }
4375 
4376   case AMDGPUISD::BFE_U32: {
4377     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
4378     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
4379   }
4380 
4381   case AMDGPUISD::CARRY:
4382   case AMDGPUISD::BORROW:
4383     return 31;
4384   case AMDGPUISD::FP_TO_FP16:
4385   case AMDGPUISD::FP16_ZEXT:
4386     return 16;
4387   default:
4388     return 1;
4389   }
4390 }
4391 
4392 bool AMDGPUTargetLowering::isKnownNeverNaNForTargetNode(SDValue Op,
4393                                                         const SelectionDAG &DAG,
4394                                                         bool SNaN,
4395                                                         unsigned Depth) const {
4396   unsigned Opcode = Op.getOpcode();
4397   switch (Opcode) {
4398   case AMDGPUISD::FMIN_LEGACY:
4399   case AMDGPUISD::FMAX_LEGACY: {
4400     if (SNaN)
4401       return true;
4402 
4403     // TODO: Can check no nans on one of the operands for each one, but which
4404     // one?
4405     return false;
4406   }
4407   case AMDGPUISD::FMUL_LEGACY:
4408   case AMDGPUISD::CVT_PKRTZ_F16_F32: {
4409     if (SNaN)
4410       return true;
4411     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4412            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4413   }
4414   case AMDGPUISD::FMED3:
4415   case AMDGPUISD::FMIN3:
4416   case AMDGPUISD::FMAX3:
4417   case AMDGPUISD::FMAD_FTZ: {
4418     if (SNaN)
4419       return true;
4420     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1) &&
4421            DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4422            DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4423   }
4424   case AMDGPUISD::CVT_F32_UBYTE0:
4425   case AMDGPUISD::CVT_F32_UBYTE1:
4426   case AMDGPUISD::CVT_F32_UBYTE2:
4427   case AMDGPUISD::CVT_F32_UBYTE3:
4428     return true;
4429 
4430   case AMDGPUISD::RCP:
4431   case AMDGPUISD::RSQ:
4432   case AMDGPUISD::RCP_LEGACY:
4433   case AMDGPUISD::RSQ_LEGACY:
4434   case AMDGPUISD::RSQ_CLAMP: {
4435     if (SNaN)
4436       return true;
4437 
4438     // TODO: Need is known positive check.
4439     return false;
4440   }
4441   case AMDGPUISD::LDEXP:
4442   case AMDGPUISD::FRACT: {
4443     if (SNaN)
4444       return true;
4445     return DAG.isKnownNeverNaN(Op.getOperand(0), SNaN, Depth + 1);
4446   }
4447   case AMDGPUISD::DIV_SCALE:
4448   case AMDGPUISD::DIV_FMAS:
4449   case AMDGPUISD::DIV_FIXUP:
4450   case AMDGPUISD::TRIG_PREOP:
4451     // TODO: Refine on operands.
4452     return SNaN;
4453   case AMDGPUISD::SIN_HW:
4454   case AMDGPUISD::COS_HW: {
4455     // TODO: Need check for infinity
4456     return SNaN;
4457   }
4458   case ISD::INTRINSIC_WO_CHAIN: {
4459     unsigned IntrinsicID
4460       = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
4461     // TODO: Handle more intrinsics
4462     switch (IntrinsicID) {
4463     case Intrinsic::amdgcn_cubeid:
4464       return true;
4465 
4466     case Intrinsic::amdgcn_frexp_mant: {
4467       if (SNaN)
4468         return true;
4469       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1);
4470     }
4471     case Intrinsic::amdgcn_cvt_pkrtz: {
4472       if (SNaN)
4473         return true;
4474       return DAG.isKnownNeverNaN(Op.getOperand(1), SNaN, Depth + 1) &&
4475              DAG.isKnownNeverNaN(Op.getOperand(2), SNaN, Depth + 1);
4476     }
4477     case Intrinsic::amdgcn_fdot2:
4478       // TODO: Refine on operand
4479       return SNaN;
4480     default:
4481       return false;
4482     }
4483   }
4484   default:
4485     return false;
4486   }
4487 }
4488 
4489 TargetLowering::AtomicExpansionKind
4490 AMDGPUTargetLowering::shouldExpandAtomicRMWInIR(AtomicRMWInst *RMW) const {
4491   if (RMW->getOperation() == AtomicRMWInst::Nand)
4492     return AtomicExpansionKind::CmpXChg;
4493   return AtomicExpansionKind::None;
4494 }
4495