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