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 /// \brief This is the parent TargetLowering class for hardware code gen
12 /// targets.
13 //
14 //===----------------------------------------------------------------------===//
15 
16 #include "AMDGPUISelLowering.h"
17 #include "AMDGPU.h"
18 #include "AMDGPUFrameLowering.h"
19 #include "AMDGPUIntrinsicInfo.h"
20 #include "AMDGPURegisterInfo.h"
21 #include "AMDGPUSubtarget.h"
22 #include "R600MachineFunctionInfo.h"
23 #include "SIMachineFunctionInfo.h"
24 #include "llvm/CodeGen/CallingConvLower.h"
25 #include "llvm/CodeGen/MachineFunction.h"
26 #include "llvm/CodeGen/MachineRegisterInfo.h"
27 #include "llvm/CodeGen/SelectionDAG.h"
28 #include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
29 #include "llvm/IR/DataLayout.h"
30 #include "llvm/IR/DiagnosticInfo.h"
31 #include "SIInstrInfo.h"
32 using namespace llvm;
33 
34 static bool allocateStack(unsigned ValNo, MVT ValVT, MVT LocVT,
35                       CCValAssign::LocInfo LocInfo,
36                       ISD::ArgFlagsTy ArgFlags, CCState &State) {
37   unsigned Offset = State.AllocateStack(ValVT.getStoreSize(),
38                                         ArgFlags.getOrigAlign());
39   State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo));
40 
41   return true;
42 }
43 
44 #include "AMDGPUGenCallingConv.inc"
45 
46 // Find a larger type to do a load / store of a vector with.
47 EVT AMDGPUTargetLowering::getEquivalentMemType(LLVMContext &Ctx, EVT VT) {
48   unsigned StoreSize = VT.getStoreSizeInBits();
49   if (StoreSize <= 32)
50     return EVT::getIntegerVT(Ctx, StoreSize);
51 
52   assert(StoreSize % 32 == 0 && "Store size not a multiple of 32");
53   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
54 }
55 
56 // Type for a vector that will be loaded to.
57 EVT AMDGPUTargetLowering::getEquivalentLoadRegType(LLVMContext &Ctx, EVT VT) {
58   unsigned StoreSize = VT.getStoreSizeInBits();
59   if (StoreSize <= 32)
60     return EVT::getIntegerVT(Ctx, 32);
61 
62   return EVT::getVectorVT(Ctx, MVT::i32, StoreSize / 32);
63 }
64 
65 AMDGPUTargetLowering::AMDGPUTargetLowering(TargetMachine &TM,
66                                            const AMDGPUSubtarget &STI)
67     : TargetLowering(TM), Subtarget(&STI) {
68   setOperationAction(ISD::Constant, MVT::i32, Legal);
69   setOperationAction(ISD::Constant, MVT::i64, Legal);
70   setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
71   setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
72 
73   setOperationAction(ISD::BR_JT, MVT::Other, Expand);
74   setOperationAction(ISD::BRIND, MVT::Other, Expand);
75 
76   // This is totally unsupported, just custom lower to produce an error.
77   setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom);
78 
79   // We need to custom lower some of the intrinsics
80   setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
81 
82   // Library functions.  These default to Expand, but we have instructions
83   // for them.
84   setOperationAction(ISD::FCEIL,  MVT::f32, Legal);
85   setOperationAction(ISD::FEXP2,  MVT::f32, Legal);
86   setOperationAction(ISD::FPOW,   MVT::f32, Legal);
87   setOperationAction(ISD::FLOG2,  MVT::f32, Legal);
88   setOperationAction(ISD::FABS,   MVT::f32, Legal);
89   setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
90   setOperationAction(ISD::FRINT,  MVT::f32, Legal);
91   setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
92   setOperationAction(ISD::FMINNUM, MVT::f32, Legal);
93   setOperationAction(ISD::FMAXNUM, MVT::f32, Legal);
94 
95   setOperationAction(ISD::FROUND, MVT::f32, Custom);
96   setOperationAction(ISD::FROUND, MVT::f64, Custom);
97 
98   setOperationAction(ISD::FREM, MVT::f32, Custom);
99   setOperationAction(ISD::FREM, MVT::f64, Custom);
100 
101   // v_mad_f32 does not support denormals according to some sources.
102   if (!Subtarget->hasFP32Denormals())
103     setOperationAction(ISD::FMAD, MVT::f32, Legal);
104 
105   // Expand to fneg + fadd.
106   setOperationAction(ISD::FSUB, MVT::f64, Expand);
107 
108   // Lower floating point store/load to integer store/load to reduce the number
109   // of patterns in tablegen.
110   setOperationAction(ISD::STORE, MVT::f32, Promote);
111   AddPromotedToType(ISD::STORE, MVT::f32, MVT::i32);
112 
113   setOperationAction(ISD::STORE, MVT::v2f32, Promote);
114   AddPromotedToType(ISD::STORE, MVT::v2f32, MVT::v2i32);
115 
116   setOperationAction(ISD::STORE, MVT::v4f32, Promote);
117   AddPromotedToType(ISD::STORE, MVT::v4f32, MVT::v4i32);
118 
119   setOperationAction(ISD::STORE, MVT::v8f32, Promote);
120   AddPromotedToType(ISD::STORE, MVT::v8f32, MVT::v8i32);
121 
122   setOperationAction(ISD::STORE, MVT::v16f32, Promote);
123   AddPromotedToType(ISD::STORE, MVT::v16f32, MVT::v16i32);
124 
125   setOperationAction(ISD::STORE, MVT::f64, Promote);
126   AddPromotedToType(ISD::STORE, MVT::f64, MVT::i64);
127 
128   setOperationAction(ISD::STORE, MVT::v2f64, Promote);
129   AddPromotedToType(ISD::STORE, MVT::v2f64, MVT::v2i64);
130 
131   // Custom lowering of vector stores is required for local address space
132   // stores.
133   setOperationAction(ISD::STORE, MVT::v4i32, Custom);
134 
135   setTruncStoreAction(MVT::v2i32, MVT::v2i16, Custom);
136   setTruncStoreAction(MVT::v2i32, MVT::v2i8, Custom);
137   setTruncStoreAction(MVT::v4i32, MVT::v4i8, Custom);
138 
139   // XXX: This can be change to Custom, once ExpandVectorStores can
140   // handle 64-bit stores.
141   setTruncStoreAction(MVT::v4i32, MVT::v4i16, Expand);
142 
143   setTruncStoreAction(MVT::i64, MVT::i16, Expand);
144   setTruncStoreAction(MVT::i64, MVT::i8, Expand);
145   setTruncStoreAction(MVT::i64, MVT::i1, Expand);
146   setTruncStoreAction(MVT::v2i64, MVT::v2i1, Expand);
147   setTruncStoreAction(MVT::v4i64, MVT::v4i1, Expand);
148 
149 
150   setOperationAction(ISD::LOAD, MVT::f32, Promote);
151   AddPromotedToType(ISD::LOAD, MVT::f32, MVT::i32);
152 
153   setOperationAction(ISD::LOAD, MVT::v2f32, Promote);
154   AddPromotedToType(ISD::LOAD, MVT::v2f32, MVT::v2i32);
155 
156   setOperationAction(ISD::LOAD, MVT::v4f32, Promote);
157   AddPromotedToType(ISD::LOAD, MVT::v4f32, MVT::v4i32);
158 
159   setOperationAction(ISD::LOAD, MVT::v8f32, Promote);
160   AddPromotedToType(ISD::LOAD, MVT::v8f32, MVT::v8i32);
161 
162   setOperationAction(ISD::LOAD, MVT::v16f32, Promote);
163   AddPromotedToType(ISD::LOAD, MVT::v16f32, MVT::v16i32);
164 
165   setOperationAction(ISD::LOAD, MVT::f64, Promote);
166   AddPromotedToType(ISD::LOAD, MVT::f64, MVT::i64);
167 
168   setOperationAction(ISD::LOAD, MVT::v2f64, Promote);
169   AddPromotedToType(ISD::LOAD, MVT::v2f64, MVT::v2i64);
170 
171   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4i32, Custom);
172   setOperationAction(ISD::CONCAT_VECTORS, MVT::v4f32, Custom);
173   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8i32, Custom);
174   setOperationAction(ISD::CONCAT_VECTORS, MVT::v8f32, Custom);
175   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2f32, Custom);
176   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v2i32, Custom);
177   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4f32, Custom);
178   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v4i32, Custom);
179   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8f32, Custom);
180   setOperationAction(ISD::EXTRACT_SUBVECTOR, MVT::v8i32, Custom);
181 
182   // There are no 64-bit extloads. These should be done as a 32-bit extload and
183   // an extension to 64-bit.
184   for (MVT VT : MVT::integer_valuetypes()) {
185     setLoadExtAction(ISD::EXTLOAD, MVT::i64, VT, Expand);
186     setLoadExtAction(ISD::SEXTLOAD, MVT::i64, VT, Expand);
187     setLoadExtAction(ISD::ZEXTLOAD, MVT::i64, VT, Expand);
188   }
189 
190   for (MVT VT : MVT::integer_vector_valuetypes()) {
191     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i8, Expand);
192     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i8, Expand);
193     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i8, Expand);
194     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i8, Expand);
195     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i8, Expand);
196     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i8, Expand);
197     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v2i16, Expand);
198     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v2i16, Expand);
199     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v2i16, Expand);
200     setLoadExtAction(ISD::EXTLOAD, VT, MVT::v4i16, Expand);
201     setLoadExtAction(ISD::SEXTLOAD, VT, MVT::v4i16, Expand);
202     setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::v4i16, Expand);
203   }
204 
205   setOperationAction(ISD::BR_CC, MVT::i1, Expand);
206 
207   if (Subtarget->getGeneration() < AMDGPUSubtarget::SEA_ISLANDS) {
208     setOperationAction(ISD::FCEIL, MVT::f64, Custom);
209     setOperationAction(ISD::FTRUNC, MVT::f64, Custom);
210     setOperationAction(ISD::FRINT, MVT::f64, Custom);
211     setOperationAction(ISD::FFLOOR, MVT::f64, Custom);
212   }
213 
214   if (!Subtarget->hasBFI()) {
215     // fcopysign can be done in a single instruction with BFI.
216     setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
217     setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
218   }
219 
220   setOperationAction(ISD::FP16_TO_FP, MVT::f64, Expand);
221 
222   setLoadExtAction(ISD::EXTLOAD, MVT::f32, MVT::f16, Expand);
223   setLoadExtAction(ISD::EXTLOAD, MVT::v2f32, MVT::v2f16, Expand);
224   setLoadExtAction(ISD::EXTLOAD, MVT::v4f32, MVT::v4f16, Expand);
225   setLoadExtAction(ISD::EXTLOAD, MVT::v8f32, MVT::v8f16, Expand);
226 
227   setLoadExtAction(ISD::EXTLOAD, MVT::f64, MVT::f16, Expand);
228   setLoadExtAction(ISD::EXTLOAD, MVT::v2f64, MVT::v2f16, Expand);
229   setLoadExtAction(ISD::EXTLOAD, MVT::v4f64, MVT::v4f16, Expand);
230   setLoadExtAction(ISD::EXTLOAD, MVT::v8f64, MVT::v8f16, Expand);
231 
232   setTruncStoreAction(MVT::f32, MVT::f16, Expand);
233   setTruncStoreAction(MVT::v2f32, MVT::v2f16, Expand);
234   setTruncStoreAction(MVT::v4f32, MVT::v4f16, Expand);
235   setTruncStoreAction(MVT::v8f32, MVT::v8f16, Expand);
236 
237   setTruncStoreAction(MVT::f64, MVT::f16, Expand);
238   setTruncStoreAction(MVT::f64, MVT::f32, Expand);
239 
240   const MVT ScalarIntVTs[] = { MVT::i32, MVT::i64 };
241   for (MVT VT : ScalarIntVTs) {
242     setOperationAction(ISD::SREM, VT, Expand);
243     setOperationAction(ISD::SDIV, VT, Expand);
244 
245     // GPU does not have divrem function for signed or unsigned.
246     setOperationAction(ISD::SDIVREM, VT, Custom);
247     setOperationAction(ISD::UDIVREM, VT, Custom);
248 
249     // GPU does not have [S|U]MUL_LOHI functions as a single instruction.
250     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
251     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
252 
253     setOperationAction(ISD::BSWAP, VT, Expand);
254     setOperationAction(ISD::CTTZ, VT, Expand);
255     setOperationAction(ISD::CTLZ, VT, Expand);
256   }
257 
258   if (!Subtarget->hasBCNT(32))
259     setOperationAction(ISD::CTPOP, MVT::i32, Expand);
260 
261   if (!Subtarget->hasBCNT(64))
262     setOperationAction(ISD::CTPOP, MVT::i64, Expand);
263 
264   // The hardware supports 32-bit ROTR, but not ROTL.
265   setOperationAction(ISD::ROTL, MVT::i32, Expand);
266   setOperationAction(ISD::ROTL, MVT::i64, Expand);
267   setOperationAction(ISD::ROTR, MVT::i64, Expand);
268 
269   setOperationAction(ISD::MUL, MVT::i64, Expand);
270   setOperationAction(ISD::MULHU, MVT::i64, Expand);
271   setOperationAction(ISD::MULHS, MVT::i64, Expand);
272   setOperationAction(ISD::UDIV, MVT::i32, Expand);
273   setOperationAction(ISD::UREM, MVT::i32, Expand);
274   setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
275   setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
276   setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
277   setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
278   setOperationAction(ISD::SELECT_CC, MVT::i64, Expand);
279 
280   setOperationAction(ISD::SMIN, MVT::i32, Legal);
281   setOperationAction(ISD::UMIN, MVT::i32, Legal);
282   setOperationAction(ISD::SMAX, MVT::i32, Legal);
283   setOperationAction(ISD::UMAX, MVT::i32, Legal);
284 
285   if (Subtarget->hasFFBH())
286     setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i32, Custom);
287 
288   if (Subtarget->hasFFBL())
289     setOperationAction(ISD::CTTZ_ZERO_UNDEF, MVT::i32, Legal);
290 
291   setOperationAction(ISD::CTLZ, MVT::i64, Custom);
292   setOperationAction(ISD::CTLZ_ZERO_UNDEF, MVT::i64, Custom);
293 
294   // We only really have 32-bit BFE instructions (and 16-bit on VI).
295   //
296   // On SI+ there are 64-bit BFEs, but they are scalar only and there isn't any
297   // effort to match them now. We want this to be false for i64 cases when the
298   // extraction isn't restricted to the upper or lower half. Ideally we would
299   // have some pass reduce 64-bit extracts to 32-bit if possible. Extracts that
300   // span the midpoint are probably relatively rare, so don't worry about them
301   // for now.
302   if (Subtarget->hasBFE())
303     setHasExtractBitsInsn(true);
304 
305   static const MVT::SimpleValueType VectorIntTypes[] = {
306     MVT::v2i32, MVT::v4i32
307   };
308 
309   for (MVT VT : VectorIntTypes) {
310     // Expand the following operations for the current type by default.
311     setOperationAction(ISD::ADD,  VT, Expand);
312     setOperationAction(ISD::AND,  VT, Expand);
313     setOperationAction(ISD::FP_TO_SINT, VT, Expand);
314     setOperationAction(ISD::FP_TO_UINT, VT, Expand);
315     setOperationAction(ISD::MUL,  VT, Expand);
316     setOperationAction(ISD::OR,   VT, Expand);
317     setOperationAction(ISD::SHL,  VT, Expand);
318     setOperationAction(ISD::SRA,  VT, Expand);
319     setOperationAction(ISD::SRL,  VT, Expand);
320     setOperationAction(ISD::ROTL, VT, Expand);
321     setOperationAction(ISD::ROTR, VT, Expand);
322     setOperationAction(ISD::SUB,  VT, Expand);
323     setOperationAction(ISD::SINT_TO_FP, VT, Expand);
324     setOperationAction(ISD::UINT_TO_FP, VT, Expand);
325     setOperationAction(ISD::SDIV, VT, Expand);
326     setOperationAction(ISD::UDIV, VT, Expand);
327     setOperationAction(ISD::SREM, VT, Expand);
328     setOperationAction(ISD::UREM, VT, Expand);
329     setOperationAction(ISD::SMUL_LOHI, VT, Expand);
330     setOperationAction(ISD::UMUL_LOHI, VT, Expand);
331     setOperationAction(ISD::SDIVREM, VT, Custom);
332     setOperationAction(ISD::UDIVREM, VT, Expand);
333     setOperationAction(ISD::ADDC, VT, Expand);
334     setOperationAction(ISD::SUBC, VT, Expand);
335     setOperationAction(ISD::ADDE, VT, Expand);
336     setOperationAction(ISD::SUBE, VT, Expand);
337     setOperationAction(ISD::SELECT, VT, Expand);
338     setOperationAction(ISD::VSELECT, VT, Expand);
339     setOperationAction(ISD::SELECT_CC, VT, Expand);
340     setOperationAction(ISD::XOR,  VT, Expand);
341     setOperationAction(ISD::BSWAP, VT, Expand);
342     setOperationAction(ISD::CTPOP, VT, Expand);
343     setOperationAction(ISD::CTTZ, VT, Expand);
344     setOperationAction(ISD::CTLZ, VT, Expand);
345     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
346   }
347 
348   static const MVT::SimpleValueType FloatVectorTypes[] = {
349     MVT::v2f32, MVT::v4f32
350   };
351 
352   for (MVT VT : FloatVectorTypes) {
353     setOperationAction(ISD::FABS, VT, Expand);
354     setOperationAction(ISD::FMINNUM, VT, Expand);
355     setOperationAction(ISD::FMAXNUM, VT, Expand);
356     setOperationAction(ISD::FADD, VT, Expand);
357     setOperationAction(ISD::FCEIL, VT, Expand);
358     setOperationAction(ISD::FCOS, VT, Expand);
359     setOperationAction(ISD::FDIV, VT, Expand);
360     setOperationAction(ISD::FEXP2, VT, Expand);
361     setOperationAction(ISD::FLOG2, VT, Expand);
362     setOperationAction(ISD::FREM, VT, Expand);
363     setOperationAction(ISD::FPOW, VT, Expand);
364     setOperationAction(ISD::FFLOOR, VT, Expand);
365     setOperationAction(ISD::FTRUNC, VT, Expand);
366     setOperationAction(ISD::FMUL, VT, Expand);
367     setOperationAction(ISD::FMA, VT, Expand);
368     setOperationAction(ISD::FRINT, VT, Expand);
369     setOperationAction(ISD::FNEARBYINT, VT, Expand);
370     setOperationAction(ISD::FSQRT, VT, Expand);
371     setOperationAction(ISD::FSIN, VT, Expand);
372     setOperationAction(ISD::FSUB, VT, Expand);
373     setOperationAction(ISD::FNEG, VT, Expand);
374     setOperationAction(ISD::SELECT, VT, Expand);
375     setOperationAction(ISD::VSELECT, VT, Expand);
376     setOperationAction(ISD::SELECT_CC, VT, Expand);
377     setOperationAction(ISD::FCOPYSIGN, VT, Expand);
378     setOperationAction(ISD::VECTOR_SHUFFLE, VT, Expand);
379   }
380 
381   setOperationAction(ISD::FNEARBYINT, MVT::f32, Custom);
382   setOperationAction(ISD::FNEARBYINT, MVT::f64, Custom);
383 
384   setTargetDAGCombine(ISD::AND);
385   setTargetDAGCombine(ISD::SHL);
386   setTargetDAGCombine(ISD::SRA);
387   setTargetDAGCombine(ISD::SRL);
388   setTargetDAGCombine(ISD::MUL);
389   setTargetDAGCombine(ISD::SELECT);
390   setTargetDAGCombine(ISD::SELECT_CC);
391   setTargetDAGCombine(ISD::STORE);
392 
393   setTargetDAGCombine(ISD::FADD);
394   setTargetDAGCombine(ISD::FSUB);
395 
396   setTargetDAGCombine(ISD::BITCAST);
397 
398   setBooleanContents(ZeroOrNegativeOneBooleanContent);
399   setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
400 
401   setSchedulingPreference(Sched::RegPressure);
402   setJumpIsExpensive(true);
403 
404   // SI at least has hardware support for floating point exceptions, but no way
405   // of using or handling them is implemented. They are also optional in OpenCL
406   // (Section 7.3)
407   setHasFloatingPointExceptions(Subtarget->hasFPExceptions());
408 
409   setSelectIsExpensive(false);
410   PredictableSelectIsExpensive = false;
411 
412   setFsqrtIsCheap(true);
413 
414   // We want to find all load dependencies for long chains of stores to enable
415   // merging into very wide vectors. The problem is with vectors with > 4
416   // elements. MergeConsecutiveStores will attempt to merge these because x8/x16
417   // vectors are a legal type, even though we have to split the loads
418   // usually. When we can more precisely specify load legality per address
419   // space, we should be able to make FindBetterChain/MergeConsecutiveStores
420   // smarter so that they can figure out what to do in 2 iterations without all
421   // N > 4 stores on the same chain.
422   GatherAllAliasesMaxDepth = 16;
423 
424   // FIXME: Need to really handle these.
425   MaxStoresPerMemcpy  = 4096;
426   MaxStoresPerMemmove = 4096;
427   MaxStoresPerMemset  = 4096;
428 }
429 
430 //===----------------------------------------------------------------------===//
431 // Target Information
432 //===----------------------------------------------------------------------===//
433 
434 MVT AMDGPUTargetLowering::getVectorIdxTy(const DataLayout &) const {
435   return MVT::i32;
436 }
437 
438 bool AMDGPUTargetLowering::isSelectSupported(SelectSupportKind SelType) const {
439   return true;
440 }
441 
442 // The backend supports 32 and 64 bit floating point immediates.
443 // FIXME: Why are we reporting vectors of FP immediates as legal?
444 bool AMDGPUTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const {
445   EVT ScalarVT = VT.getScalarType();
446   return (ScalarVT == MVT::f32 || ScalarVT == MVT::f64);
447 }
448 
449 // We don't want to shrink f64 / f32 constants.
450 bool AMDGPUTargetLowering::ShouldShrinkFPConstant(EVT VT) const {
451   EVT ScalarVT = VT.getScalarType();
452   return (ScalarVT != MVT::f32 && ScalarVT != MVT::f64);
453 }
454 
455 bool AMDGPUTargetLowering::shouldReduceLoadWidth(SDNode *N,
456                                                  ISD::LoadExtType,
457                                                  EVT NewVT) const {
458 
459   unsigned NewSize = NewVT.getStoreSizeInBits();
460 
461   // If we are reducing to a 32-bit load, this is always better.
462   if (NewSize == 32)
463     return true;
464 
465   EVT OldVT = N->getValueType(0);
466   unsigned OldSize = OldVT.getStoreSizeInBits();
467 
468   // Don't produce extloads from sub 32-bit types. SI doesn't have scalar
469   // extloads, so doing one requires using a buffer_load. In cases where we
470   // still couldn't use a scalar load, using the wider load shouldn't really
471   // hurt anything.
472 
473   // If the old size already had to be an extload, there's no harm in continuing
474   // to reduce the width.
475   return (OldSize < 32);
476 }
477 
478 bool AMDGPUTargetLowering::isLoadBitCastBeneficial(EVT LoadTy,
479                                                    EVT CastTy) const {
480   if (LoadTy.getSizeInBits() != CastTy.getSizeInBits())
481     return true;
482 
483   unsigned LScalarSize = LoadTy.getScalarType().getSizeInBits();
484   unsigned CastScalarSize = CastTy.getScalarType().getSizeInBits();
485 
486   return ((LScalarSize <= CastScalarSize) ||
487           (CastScalarSize >= 32) ||
488           (LScalarSize < 32));
489 }
490 
491 // SI+ has instructions for cttz / ctlz for 32-bit values. This is probably also
492 // profitable with the expansion for 64-bit since it's generally good to
493 // speculate things.
494 // FIXME: These should really have the size as a parameter.
495 bool AMDGPUTargetLowering::isCheapToSpeculateCttz() const {
496   return true;
497 }
498 
499 bool AMDGPUTargetLowering::isCheapToSpeculateCtlz() const {
500   return true;
501 }
502 
503 //===---------------------------------------------------------------------===//
504 // Target Properties
505 //===---------------------------------------------------------------------===//
506 
507 bool AMDGPUTargetLowering::isFAbsFree(EVT VT) const {
508   assert(VT.isFloatingPoint());
509   return VT == MVT::f32 || VT == MVT::f64;
510 }
511 
512 bool AMDGPUTargetLowering::isFNegFree(EVT VT) const {
513   assert(VT.isFloatingPoint());
514   return VT == MVT::f32 || VT == MVT::f64;
515 }
516 
517 bool AMDGPUTargetLowering:: storeOfVectorConstantIsCheap(EVT MemVT,
518                                                          unsigned NumElem,
519                                                          unsigned AS) const {
520   return true;
521 }
522 
523 bool AMDGPUTargetLowering::aggressivelyPreferBuildVectorSources(EVT VecVT) const {
524   // There are few operations which truly have vector input operands. Any vector
525   // operation is going to involve operations on each component, and a
526   // build_vector will be a copy per element, so it always makes sense to use a
527   // build_vector input in place of the extracted element to avoid a copy into a
528   // super register.
529   //
530   // We should probably only do this if all users are extracts only, but this
531   // should be the common case.
532   return true;
533 }
534 
535 bool AMDGPUTargetLowering::isTruncateFree(EVT Source, EVT Dest) const {
536   // Truncate is just accessing a subregister.
537   return Dest.bitsLT(Source) && (Dest.getSizeInBits() % 32 == 0);
538 }
539 
540 bool AMDGPUTargetLowering::isTruncateFree(Type *Source, Type *Dest) const {
541   // Truncate is just accessing a subregister.
542   return Dest->getPrimitiveSizeInBits() < Source->getPrimitiveSizeInBits() &&
543          (Dest->getPrimitiveSizeInBits() % 32 == 0);
544 }
545 
546 bool AMDGPUTargetLowering::isZExtFree(Type *Src, Type *Dest) const {
547   unsigned SrcSize = Src->getScalarSizeInBits();
548   unsigned DestSize = Dest->getScalarSizeInBits();
549 
550   return SrcSize == 32 && DestSize == 64;
551 }
552 
553 bool AMDGPUTargetLowering::isZExtFree(EVT Src, EVT Dest) const {
554   // Any register load of a 64-bit value really requires 2 32-bit moves. For all
555   // practical purposes, the extra mov 0 to load a 64-bit is free.  As used,
556   // this will enable reducing 64-bit operations the 32-bit, which is always
557   // good.
558   return Src == MVT::i32 && Dest == MVT::i64;
559 }
560 
561 bool AMDGPUTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
562   return isZExtFree(Val.getValueType(), VT2);
563 }
564 
565 bool AMDGPUTargetLowering::isNarrowingProfitable(EVT SrcVT, EVT DestVT) const {
566   // There aren't really 64-bit registers, but pairs of 32-bit ones and only a
567   // limited number of native 64-bit operations. Shrinking an operation to fit
568   // in a single 32-bit register should always be helpful. As currently used,
569   // this is much less general than the name suggests, and is only used in
570   // places trying to reduce the sizes of loads. Shrinking loads to < 32-bits is
571   // not profitable, and may actually be harmful.
572   return SrcVT.getSizeInBits() > 32 && DestVT.getSizeInBits() == 32;
573 }
574 
575 //===---------------------------------------------------------------------===//
576 // TargetLowering Callbacks
577 //===---------------------------------------------------------------------===//
578 
579 void AMDGPUTargetLowering::AnalyzeFormalArguments(CCState &State,
580                              const SmallVectorImpl<ISD::InputArg> &Ins) const {
581 
582   State.AnalyzeFormalArguments(Ins, CC_AMDGPU);
583 }
584 
585 void AMDGPUTargetLowering::AnalyzeReturn(CCState &State,
586                            const SmallVectorImpl<ISD::OutputArg> &Outs) const {
587 
588   State.AnalyzeReturn(Outs, RetCC_SI);
589 }
590 
591 SDValue AMDGPUTargetLowering::LowerReturn(
592                                      SDValue Chain,
593                                      CallingConv::ID CallConv,
594                                      bool isVarArg,
595                                      const SmallVectorImpl<ISD::OutputArg> &Outs,
596                                      const SmallVectorImpl<SDValue> &OutVals,
597                                      SDLoc DL, SelectionDAG &DAG) const {
598   return DAG.getNode(AMDGPUISD::RET_FLAG, DL, MVT::Other, Chain);
599 }
600 
601 //===---------------------------------------------------------------------===//
602 // Target specific lowering
603 //===---------------------------------------------------------------------===//
604 
605 SDValue AMDGPUTargetLowering::LowerCall(CallLoweringInfo &CLI,
606                                         SmallVectorImpl<SDValue> &InVals) const {
607   SDValue Callee = CLI.Callee;
608   SelectionDAG &DAG = CLI.DAG;
609 
610   const Function &Fn = *DAG.getMachineFunction().getFunction();
611 
612   StringRef FuncName("<unknown>");
613 
614   if (const ExternalSymbolSDNode *G = dyn_cast<ExternalSymbolSDNode>(Callee))
615     FuncName = G->getSymbol();
616   else if (const GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
617     FuncName = G->getGlobal()->getName();
618 
619   DiagnosticInfoUnsupported NoCalls(
620       Fn, "unsupported call to function " + FuncName, CLI.DL.getDebugLoc());
621   DAG.getContext()->diagnose(NoCalls);
622   return SDValue();
623 }
624 
625 SDValue AMDGPUTargetLowering::LowerDYNAMIC_STACKALLOC(SDValue Op,
626                                                       SelectionDAG &DAG) const {
627   const Function &Fn = *DAG.getMachineFunction().getFunction();
628 
629   DiagnosticInfoUnsupported NoDynamicAlloca(Fn, "unsupported dynamic alloca",
630                                             SDLoc(Op).getDebugLoc());
631   DAG.getContext()->diagnose(NoDynamicAlloca);
632   return SDValue();
633 }
634 
635 SDValue AMDGPUTargetLowering::LowerOperation(SDValue Op,
636                                              SelectionDAG &DAG) const {
637   switch (Op.getOpcode()) {
638   default:
639     Op->dump(&DAG);
640     llvm_unreachable("Custom lowering code for this"
641                      "instruction is not implemented yet!");
642     break;
643   case ISD::SIGN_EXTEND_INREG: return LowerSIGN_EXTEND_INREG(Op, DAG);
644   case ISD::CONCAT_VECTORS: return LowerCONCAT_VECTORS(Op, DAG);
645   case ISD::EXTRACT_SUBVECTOR: return LowerEXTRACT_SUBVECTOR(Op, DAG);
646   case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
647   case ISD::UDIVREM: return LowerUDIVREM(Op, DAG);
648   case ISD::SDIVREM: return LowerSDIVREM(Op, DAG);
649   case ISD::FREM: return LowerFREM(Op, DAG);
650   case ISD::FCEIL: return LowerFCEIL(Op, DAG);
651   case ISD::FTRUNC: return LowerFTRUNC(Op, DAG);
652   case ISD::FRINT: return LowerFRINT(Op, DAG);
653   case ISD::FNEARBYINT: return LowerFNEARBYINT(Op, DAG);
654   case ISD::FROUND: return LowerFROUND(Op, DAG);
655   case ISD::FFLOOR: return LowerFFLOOR(Op, DAG);
656   case ISD::SINT_TO_FP: return LowerSINT_TO_FP(Op, DAG);
657   case ISD::UINT_TO_FP: return LowerUINT_TO_FP(Op, DAG);
658   case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG);
659   case ISD::FP_TO_UINT: return LowerFP_TO_UINT(Op, DAG);
660   case ISD::CTLZ:
661   case ISD::CTLZ_ZERO_UNDEF:
662     return LowerCTLZ(Op, DAG);
663   case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG);
664   }
665   return Op;
666 }
667 
668 void AMDGPUTargetLowering::ReplaceNodeResults(SDNode *N,
669                                               SmallVectorImpl<SDValue> &Results,
670                                               SelectionDAG &DAG) const {
671   switch (N->getOpcode()) {
672   case ISD::SIGN_EXTEND_INREG:
673     // Different parts of legalization seem to interpret which type of
674     // sign_extend_inreg is the one to check for custom lowering. The extended
675     // from type is what really matters, but some places check for custom
676     // lowering of the result type. This results in trying to use
677     // ReplaceNodeResults to sext_in_reg to an illegal type, so we'll just do
678     // nothing here and let the illegal result integer be handled normally.
679     return;
680   default:
681     return;
682   }
683 }
684 
685 // FIXME: This implements accesses to initialized globals in the constant
686 // address space by copying them to private and accessing that. It does not
687 // properly handle illegal types or vectors. The private vector loads are not
688 // scalarized, and the illegal scalars hit an assertion. This technique will not
689 // work well with large initializers, and this should eventually be
690 // removed. Initialized globals should be placed into a data section that the
691 // runtime will load into a buffer before the kernel is executed. Uses of the
692 // global need to be replaced with a pointer loaded from an implicit kernel
693 // argument into this buffer holding the copy of the data, which will remove the
694 // need for any of this.
695 SDValue AMDGPUTargetLowering::LowerConstantInitializer(const Constant* Init,
696                                                        const GlobalValue *GV,
697                                                        const SDValue &InitPtr,
698                                                        SDValue Chain,
699                                                        SelectionDAG &DAG) const {
700   const DataLayout &TD = DAG.getDataLayout();
701   SDLoc DL(InitPtr);
702   Type *InitTy = Init->getType();
703 
704   if (const ConstantInt *CI = dyn_cast<ConstantInt>(Init)) {
705     EVT VT = EVT::getEVT(InitTy);
706     PointerType *PtrTy = PointerType::get(InitTy, AMDGPUAS::PRIVATE_ADDRESS);
707     return DAG.getStore(Chain, DL, DAG.getConstant(*CI, DL, VT), InitPtr,
708                         MachinePointerInfo(UndefValue::get(PtrTy)), false,
709                         false, TD.getPrefTypeAlignment(InitTy));
710   }
711 
712   if (const ConstantFP *CFP = dyn_cast<ConstantFP>(Init)) {
713     EVT VT = EVT::getEVT(CFP->getType());
714     PointerType *PtrTy = PointerType::get(CFP->getType(), 0);
715     return DAG.getStore(Chain, DL, DAG.getConstantFP(*CFP, DL, VT), InitPtr,
716                         MachinePointerInfo(UndefValue::get(PtrTy)), false,
717                         false, TD.getPrefTypeAlignment(CFP->getType()));
718   }
719 
720   if (StructType *ST = dyn_cast<StructType>(InitTy)) {
721     const StructLayout *SL = TD.getStructLayout(ST);
722 
723     EVT PtrVT = InitPtr.getValueType();
724     SmallVector<SDValue, 8> Chains;
725 
726     for (unsigned I = 0, N = ST->getNumElements(); I != N; ++I) {
727       SDValue Offset = DAG.getConstant(SL->getElementOffset(I), DL, PtrVT);
728       SDValue Ptr = DAG.getNode(ISD::ADD, DL, PtrVT, InitPtr, Offset);
729 
730       Constant *Elt = Init->getAggregateElement(I);
731       Chains.push_back(LowerConstantInitializer(Elt, GV, Ptr, Chain, DAG));
732     }
733 
734     return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Chains);
735   }
736 
737   if (SequentialType *SeqTy = dyn_cast<SequentialType>(InitTy)) {
738     EVT PtrVT = InitPtr.getValueType();
739 
740     unsigned NumElements;
741     if (ArrayType *AT = dyn_cast<ArrayType>(SeqTy))
742       NumElements = AT->getNumElements();
743     else if (VectorType *VT = dyn_cast<VectorType>(SeqTy))
744       NumElements = VT->getNumElements();
745     else
746       llvm_unreachable("Unexpected type");
747 
748     unsigned EltSize = TD.getTypeAllocSize(SeqTy->getElementType());
749     SmallVector<SDValue, 8> Chains;
750     for (unsigned i = 0; i < NumElements; ++i) {
751       SDValue Offset = DAG.getConstant(i * EltSize, DL, PtrVT);
752       SDValue Ptr = DAG.getNode(ISD::ADD, DL, PtrVT, InitPtr, Offset);
753 
754       Constant *Elt = Init->getAggregateElement(i);
755       Chains.push_back(LowerConstantInitializer(Elt, GV, Ptr, Chain, DAG));
756     }
757 
758     return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Chains);
759   }
760 
761   if (isa<UndefValue>(Init)) {
762     EVT VT = EVT::getEVT(InitTy);
763     PointerType *PtrTy = PointerType::get(InitTy, AMDGPUAS::PRIVATE_ADDRESS);
764     return DAG.getStore(Chain, DL, DAG.getUNDEF(VT), InitPtr,
765                         MachinePointerInfo(UndefValue::get(PtrTy)), false,
766                         false, TD.getPrefTypeAlignment(InitTy));
767   }
768 
769   Init->dump();
770   llvm_unreachable("Unhandled constant initializer");
771 }
772 
773 static bool hasDefinedInitializer(const GlobalValue *GV) {
774   const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV);
775   if (!GVar || !GVar->hasInitializer())
776     return false;
777 
778   return !isa<UndefValue>(GVar->getInitializer());
779 }
780 
781 SDValue AMDGPUTargetLowering::LowerGlobalAddress(AMDGPUMachineFunction* MFI,
782                                                  SDValue Op,
783                                                  SelectionDAG &DAG) const {
784 
785   const DataLayout &DL = DAG.getDataLayout();
786   GlobalAddressSDNode *G = cast<GlobalAddressSDNode>(Op);
787   const GlobalValue *GV = G->getGlobal();
788 
789   switch (G->getAddressSpace()) {
790   case AMDGPUAS::LOCAL_ADDRESS: {
791     // XXX: What does the value of G->getOffset() mean?
792     assert(G->getOffset() == 0 &&
793          "Do not know what to do with an non-zero offset");
794 
795     // TODO: We could emit code to handle the initialization somewhere.
796     if (hasDefinedInitializer(GV))
797       break;
798 
799     unsigned Offset;
800     if (MFI->LocalMemoryObjects.count(GV) == 0) {
801       unsigned Align = GV->getAlignment();
802       if (Align == 0)
803         Align = DL.getABITypeAlignment(GV->getValueType());
804 
805       /// TODO: We should sort these to minimize wasted space due to alignment
806       /// padding. Currently the padding is decided by the first encountered use
807       /// during lowering.
808       Offset = MFI->LDSSize = alignTo(MFI->LDSSize, Align);
809       MFI->LocalMemoryObjects[GV] = Offset;
810       MFI->LDSSize += DL.getTypeAllocSize(GV->getValueType());
811     } else {
812       Offset = MFI->LocalMemoryObjects[GV];
813     }
814 
815     return DAG.getConstant(Offset, SDLoc(Op),
816                            getPointerTy(DL, AMDGPUAS::LOCAL_ADDRESS));
817   }
818   }
819 
820   const Function &Fn = *DAG.getMachineFunction().getFunction();
821   DiagnosticInfoUnsupported BadInit(
822       Fn, "unsupported initializer for address space", SDLoc(Op).getDebugLoc());
823   DAG.getContext()->diagnose(BadInit);
824   return SDValue();
825 }
826 
827 SDValue AMDGPUTargetLowering::LowerCONCAT_VECTORS(SDValue Op,
828                                                   SelectionDAG &DAG) const {
829   SmallVector<SDValue, 8> Args;
830 
831   for (const SDUse &U : Op->ops())
832     DAG.ExtractVectorElements(U.get(), Args);
833 
834   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
835 }
836 
837 SDValue AMDGPUTargetLowering::LowerEXTRACT_SUBVECTOR(SDValue Op,
838                                                      SelectionDAG &DAG) const {
839 
840   SmallVector<SDValue, 8> Args;
841   unsigned Start = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
842   EVT VT = Op.getValueType();
843   DAG.ExtractVectorElements(Op.getOperand(0), Args, Start,
844                             VT.getVectorNumElements());
845 
846   return DAG.getBuildVector(Op.getValueType(), SDLoc(Op), Args);
847 }
848 
849 SDValue AMDGPUTargetLowering::LowerINTRINSIC_WO_CHAIN(SDValue Op,
850     SelectionDAG &DAG) const {
851   unsigned IntrinsicID = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
852   SDLoc DL(Op);
853   EVT VT = Op.getValueType();
854 
855   switch (IntrinsicID) {
856     default: return Op;
857     case AMDGPUIntrinsic::AMDGPU_clamp:
858     case AMDGPUIntrinsic::AMDIL_clamp: // Legacy name.
859       return DAG.getNode(AMDGPUISD::CLAMP, DL, VT,
860                          Op.getOperand(1), Op.getOperand(2), Op.getOperand(3));
861 
862     case Intrinsic::AMDGPU_ldexp: // Legacy name
863       return DAG.getNode(AMDGPUISD::LDEXP, DL, VT, Op.getOperand(1),
864                                                    Op.getOperand(2));
865 
866     case AMDGPUIntrinsic::AMDGPU_bfe_i32:
867       return DAG.getNode(AMDGPUISD::BFE_I32, DL, VT,
868                          Op.getOperand(1),
869                          Op.getOperand(2),
870                          Op.getOperand(3));
871 
872     case AMDGPUIntrinsic::AMDGPU_bfe_u32:
873       return DAG.getNode(AMDGPUISD::BFE_U32, DL, VT,
874                          Op.getOperand(1),
875                          Op.getOperand(2),
876                          Op.getOperand(3));
877 
878     case AMDGPUIntrinsic::AMDIL_exp: // Legacy name.
879       return DAG.getNode(ISD::FEXP2, DL, VT, Op.getOperand(1));
880 
881     case AMDGPUIntrinsic::AMDGPU_brev: // Legacy name
882       return DAG.getNode(ISD::BITREVERSE, DL, VT, Op.getOperand(1));
883   }
884 }
885 
886 /// \brief Generate Min/Max node
887 SDValue AMDGPUTargetLowering::CombineFMinMaxLegacy(SDLoc DL,
888                                                    EVT VT,
889                                                    SDValue LHS,
890                                                    SDValue RHS,
891                                                    SDValue True,
892                                                    SDValue False,
893                                                    SDValue CC,
894                                                    DAGCombinerInfo &DCI) const {
895   if (Subtarget->getGeneration() >= AMDGPUSubtarget::VOLCANIC_ISLANDS)
896     return SDValue();
897 
898   if (!(LHS == True && RHS == False) && !(LHS == False && RHS == True))
899     return SDValue();
900 
901   SelectionDAG &DAG = DCI.DAG;
902   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(CC)->get();
903   switch (CCOpcode) {
904   case ISD::SETOEQ:
905   case ISD::SETONE:
906   case ISD::SETUNE:
907   case ISD::SETNE:
908   case ISD::SETUEQ:
909   case ISD::SETEQ:
910   case ISD::SETFALSE:
911   case ISD::SETFALSE2:
912   case ISD::SETTRUE:
913   case ISD::SETTRUE2:
914   case ISD::SETUO:
915   case ISD::SETO:
916     break;
917   case ISD::SETULE:
918   case ISD::SETULT: {
919     if (LHS == True)
920       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
921     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
922   }
923   case ISD::SETOLE:
924   case ISD::SETOLT:
925   case ISD::SETLE:
926   case ISD::SETLT: {
927     // Ordered. Assume ordered for undefined.
928 
929     // Only do this after legalization to avoid interfering with other combines
930     // which might occur.
931     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
932         !DCI.isCalledByLegalizer())
933       return SDValue();
934 
935     // We need to permute the operands to get the correct NaN behavior. The
936     // selected operand is the second one based on the failing compare with NaN,
937     // so permute it based on the compare type the hardware uses.
938     if (LHS == True)
939       return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
940     return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
941   }
942   case ISD::SETUGE:
943   case ISD::SETUGT: {
944     if (LHS == True)
945       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, RHS, LHS);
946     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, LHS, RHS);
947   }
948   case ISD::SETGT:
949   case ISD::SETGE:
950   case ISD::SETOGE:
951   case ISD::SETOGT: {
952     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG &&
953         !DCI.isCalledByLegalizer())
954       return SDValue();
955 
956     if (LHS == True)
957       return DAG.getNode(AMDGPUISD::FMAX_LEGACY, DL, VT, LHS, RHS);
958     return DAG.getNode(AMDGPUISD::FMIN_LEGACY, DL, VT, RHS, LHS);
959   }
960   case ISD::SETCC_INVALID:
961     llvm_unreachable("Invalid setcc condcode!");
962   }
963   return SDValue();
964 }
965 
966 std::pair<SDValue, SDValue>
967 AMDGPUTargetLowering::split64BitValue(SDValue Op, SelectionDAG &DAG) const {
968   SDLoc SL(Op);
969 
970   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
971 
972   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
973   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
974 
975   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
976   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
977 
978   return std::make_pair(Lo, Hi);
979 }
980 
981 SDValue AMDGPUTargetLowering::getLoHalf64(SDValue Op, SelectionDAG &DAG) const {
982   SDLoc SL(Op);
983 
984   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
985   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
986   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
987 }
988 
989 SDValue AMDGPUTargetLowering::getHiHalf64(SDValue Op, SelectionDAG &DAG) const {
990   SDLoc SL(Op);
991 
992   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Op);
993   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
994   return DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
995 }
996 
997 SDValue AMDGPUTargetLowering::SplitVectorLoad(const SDValue Op,
998                                               SelectionDAG &DAG) const {
999   LoadSDNode *Load = cast<LoadSDNode>(Op);
1000   EVT VT = Op.getValueType();
1001 
1002 
1003   // If this is a 2 element vector, we really want to scalarize and not create
1004   // weird 1 element vectors.
1005   if (VT.getVectorNumElements() == 2)
1006     return scalarizeVectorLoad(Load, DAG);
1007 
1008   SDValue BasePtr = Load->getBasePtr();
1009   EVT PtrVT = BasePtr.getValueType();
1010   EVT MemVT = Load->getMemoryVT();
1011   SDLoc SL(Op);
1012 
1013   const MachinePointerInfo &SrcValue = Load->getMemOperand()->getPointerInfo();
1014 
1015   EVT LoVT, HiVT;
1016   EVT LoMemVT, HiMemVT;
1017   SDValue Lo, Hi;
1018 
1019   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1020   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1021   std::tie(Lo, Hi) = DAG.SplitVector(Op, SL, LoVT, HiVT);
1022 
1023   unsigned Size = LoMemVT.getStoreSize();
1024   unsigned BaseAlign = Load->getAlignment();
1025   unsigned HiAlign = MinAlign(BaseAlign, Size);
1026 
1027   SDValue LoLoad
1028     = DAG.getExtLoad(Load->getExtensionType(), SL, LoVT,
1029                      Load->getChain(), BasePtr,
1030                      SrcValue,
1031                      LoMemVT, Load->isVolatile(), Load->isNonTemporal(),
1032                      Load->isInvariant(), BaseAlign);
1033 
1034   SDValue HiPtr = DAG.getNode(ISD::ADD, SL, PtrVT, BasePtr,
1035                               DAG.getConstant(Size, SL, PtrVT));
1036 
1037   SDValue HiLoad
1038     = DAG.getExtLoad(Load->getExtensionType(), SL, HiVT,
1039                      Load->getChain(), HiPtr,
1040                      SrcValue.getWithOffset(LoMemVT.getStoreSize()),
1041                      HiMemVT, Load->isVolatile(), Load->isNonTemporal(),
1042                      Load->isInvariant(), HiAlign);
1043 
1044   SDValue Ops[] = {
1045     DAG.getNode(ISD::CONCAT_VECTORS, SL, VT, LoLoad, HiLoad),
1046     DAG.getNode(ISD::TokenFactor, SL, MVT::Other,
1047                 LoLoad.getValue(1), HiLoad.getValue(1))
1048   };
1049 
1050   return DAG.getMergeValues(Ops, SL);
1051 }
1052 
1053 // FIXME: This isn't doing anything for SI. This should be used in a target
1054 // combine during type legalization.
1055 SDValue AMDGPUTargetLowering::MergeVectorStore(const SDValue &Op,
1056                                                SelectionDAG &DAG) const {
1057   StoreSDNode *Store = cast<StoreSDNode>(Op);
1058   EVT MemVT = Store->getMemoryVT();
1059   unsigned MemBits = MemVT.getSizeInBits();
1060 
1061   // Byte stores are really expensive, so if possible, try to pack 32-bit vector
1062   // truncating store into an i32 store.
1063   // XXX: We could also handle optimize other vector bitwidths.
1064   if (!MemVT.isVector() || MemBits > 32) {
1065     return SDValue();
1066   }
1067 
1068   SDLoc DL(Op);
1069   SDValue Value = Store->getValue();
1070   EVT VT = Value.getValueType();
1071   EVT ElemVT = VT.getVectorElementType();
1072   SDValue Ptr = Store->getBasePtr();
1073   EVT MemEltVT = MemVT.getVectorElementType();
1074   unsigned MemEltBits = MemEltVT.getSizeInBits();
1075   unsigned MemNumElements = MemVT.getVectorNumElements();
1076   unsigned PackedSize = MemVT.getStoreSizeInBits();
1077   SDValue Mask = DAG.getConstant((1 << MemEltBits) - 1, DL, MVT::i32);
1078 
1079   assert(Value.getValueType().getScalarSizeInBits() >= 32);
1080 
1081   SDValue PackedValue;
1082   for (unsigned i = 0; i < MemNumElements; ++i) {
1083     SDValue Elt = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, DL, ElemVT, Value,
1084                               DAG.getConstant(i, DL, MVT::i32));
1085     Elt = DAG.getZExtOrTrunc(Elt, DL, MVT::i32);
1086     Elt = DAG.getNode(ISD::AND, DL, MVT::i32, Elt, Mask); // getZeroExtendInReg
1087 
1088     SDValue Shift = DAG.getConstant(MemEltBits * i, DL, MVT::i32);
1089     Elt = DAG.getNode(ISD::SHL, DL, MVT::i32, Elt, Shift);
1090 
1091     if (i == 0) {
1092       PackedValue = Elt;
1093     } else {
1094       PackedValue = DAG.getNode(ISD::OR, DL, MVT::i32, PackedValue, Elt);
1095     }
1096   }
1097 
1098   if (PackedSize < 32) {
1099     EVT PackedVT = EVT::getIntegerVT(*DAG.getContext(), PackedSize);
1100     return DAG.getTruncStore(Store->getChain(), DL, PackedValue, Ptr,
1101                              Store->getMemOperand()->getPointerInfo(),
1102                              PackedVT,
1103                              Store->isNonTemporal(), Store->isVolatile(),
1104                              Store->getAlignment());
1105   }
1106 
1107   return DAG.getStore(Store->getChain(), DL, PackedValue, Ptr,
1108                       Store->getMemOperand()->getPointerInfo(),
1109                       Store->isVolatile(),  Store->isNonTemporal(),
1110                       Store->getAlignment());
1111 }
1112 
1113 SDValue AMDGPUTargetLowering::SplitVectorStore(SDValue Op,
1114                                                SelectionDAG &DAG) const {
1115   StoreSDNode *Store = cast<StoreSDNode>(Op);
1116   SDValue Val = Store->getValue();
1117   EVT VT = Val.getValueType();
1118 
1119   // If this is a 2 element vector, we really want to scalarize and not create
1120   // weird 1 element vectors.
1121   if (VT.getVectorNumElements() == 2)
1122     return scalarizeVectorStore(Store, DAG);
1123 
1124   EVT MemVT = Store->getMemoryVT();
1125   SDValue Chain = Store->getChain();
1126   SDValue BasePtr = Store->getBasePtr();
1127   SDLoc SL(Op);
1128 
1129   EVT LoVT, HiVT;
1130   EVT LoMemVT, HiMemVT;
1131   SDValue Lo, Hi;
1132 
1133   std::tie(LoVT, HiVT) = DAG.GetSplitDestVTs(VT);
1134   std::tie(LoMemVT, HiMemVT) = DAG.GetSplitDestVTs(MemVT);
1135   std::tie(Lo, Hi) = DAG.SplitVector(Val, SL, LoVT, HiVT);
1136 
1137   EVT PtrVT = BasePtr.getValueType();
1138   SDValue HiPtr = DAG.getNode(ISD::ADD, SL, PtrVT, BasePtr,
1139                               DAG.getConstant(LoMemVT.getStoreSize(), SL,
1140                                               PtrVT));
1141 
1142   const MachinePointerInfo &SrcValue = Store->getMemOperand()->getPointerInfo();
1143   unsigned BaseAlign = Store->getAlignment();
1144   unsigned Size = LoMemVT.getStoreSize();
1145   unsigned HiAlign = MinAlign(BaseAlign, Size);
1146 
1147   SDValue LoStore
1148     = DAG.getTruncStore(Chain, SL, Lo,
1149                         BasePtr,
1150                         SrcValue,
1151                         LoMemVT,
1152                         Store->isNonTemporal(),
1153                         Store->isVolatile(),
1154                         BaseAlign);
1155   SDValue HiStore
1156     = DAG.getTruncStore(Chain, SL, Hi,
1157                         HiPtr,
1158                         SrcValue.getWithOffset(Size),
1159                         HiMemVT,
1160                         Store->isNonTemporal(),
1161                         Store->isVolatile(),
1162                         HiAlign);
1163 
1164   return DAG.getNode(ISD::TokenFactor, SL, MVT::Other, LoStore, HiStore);
1165 }
1166 
1167 // This is a shortcut for integer division because we have fast i32<->f32
1168 // conversions, and fast f32 reciprocal instructions. The fractional part of a
1169 // float is enough to accurately represent up to a 24-bit integer.
1170 SDValue AMDGPUTargetLowering::LowerDIVREM24(SDValue Op, SelectionDAG &DAG, bool sign) const {
1171   SDLoc DL(Op);
1172   EVT VT = Op.getValueType();
1173   SDValue LHS = Op.getOperand(0);
1174   SDValue RHS = Op.getOperand(1);
1175   MVT IntVT = MVT::i32;
1176   MVT FltVT = MVT::f32;
1177 
1178   ISD::NodeType ToFp  = sign ? ISD::SINT_TO_FP : ISD::UINT_TO_FP;
1179   ISD::NodeType ToInt = sign ? ISD::FP_TO_SINT : ISD::FP_TO_UINT;
1180 
1181   if (VT.isVector()) {
1182     unsigned NElts = VT.getVectorNumElements();
1183     IntVT = MVT::getVectorVT(MVT::i32, NElts);
1184     FltVT = MVT::getVectorVT(MVT::f32, NElts);
1185   }
1186 
1187   unsigned BitSize = VT.getScalarType().getSizeInBits();
1188 
1189   SDValue jq = DAG.getConstant(1, DL, IntVT);
1190 
1191   if (sign) {
1192     // char|short jq = ia ^ ib;
1193     jq = DAG.getNode(ISD::XOR, DL, VT, LHS, RHS);
1194 
1195     // jq = jq >> (bitsize - 2)
1196     jq = DAG.getNode(ISD::SRA, DL, VT, jq,
1197                      DAG.getConstant(BitSize - 2, DL, VT));
1198 
1199     // jq = jq | 0x1
1200     jq = DAG.getNode(ISD::OR, DL, VT, jq, DAG.getConstant(1, DL, VT));
1201 
1202     // jq = (int)jq
1203     jq = DAG.getSExtOrTrunc(jq, DL, IntVT);
1204   }
1205 
1206   // int ia = (int)LHS;
1207   SDValue ia = sign ?
1208     DAG.getSExtOrTrunc(LHS, DL, IntVT) : DAG.getZExtOrTrunc(LHS, DL, IntVT);
1209 
1210   // int ib, (int)RHS;
1211   SDValue ib = sign ?
1212     DAG.getSExtOrTrunc(RHS, DL, IntVT) : DAG.getZExtOrTrunc(RHS, DL, IntVT);
1213 
1214   // float fa = (float)ia;
1215   SDValue fa = DAG.getNode(ToFp, DL, FltVT, ia);
1216 
1217   // float fb = (float)ib;
1218   SDValue fb = DAG.getNode(ToFp, DL, FltVT, ib);
1219 
1220   // TODO: Should this propagate fast-math-flags?
1221   // float fq = native_divide(fa, fb);
1222   SDValue fq = DAG.getNode(ISD::FMUL, DL, FltVT,
1223                            fa, DAG.getNode(AMDGPUISD::RCP, DL, FltVT, fb));
1224 
1225   // fq = trunc(fq);
1226   fq = DAG.getNode(ISD::FTRUNC, DL, FltVT, fq);
1227 
1228   // float fqneg = -fq;
1229   SDValue fqneg = DAG.getNode(ISD::FNEG, DL, FltVT, fq);
1230 
1231   // float fr = mad(fqneg, fb, fa);
1232   SDValue fr = DAG.getNode(ISD::FADD, DL, FltVT,
1233                            DAG.getNode(ISD::FMUL, DL, FltVT, fqneg, fb), fa);
1234 
1235   // int iq = (int)fq;
1236   SDValue iq = DAG.getNode(ToInt, DL, IntVT, fq);
1237 
1238   // fr = fabs(fr);
1239   fr = DAG.getNode(ISD::FABS, DL, FltVT, fr);
1240 
1241   // fb = fabs(fb);
1242   fb = DAG.getNode(ISD::FABS, DL, FltVT, fb);
1243 
1244   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), VT);
1245 
1246   // int cv = fr >= fb;
1247   SDValue cv = DAG.getSetCC(DL, SetCCVT, fr, fb, ISD::SETOGE);
1248 
1249   // jq = (cv ? jq : 0);
1250   jq = DAG.getNode(ISD::SELECT, DL, VT, cv, jq, DAG.getConstant(0, DL, VT));
1251 
1252   // dst = trunc/extend to legal type
1253   iq = sign ? DAG.getSExtOrTrunc(iq, DL, VT) : DAG.getZExtOrTrunc(iq, DL, VT);
1254 
1255   // dst = iq + jq;
1256   SDValue Div = DAG.getNode(ISD::ADD, DL, VT, iq, jq);
1257 
1258   // Rem needs compensation, it's easier to recompute it
1259   SDValue Rem = DAG.getNode(ISD::MUL, DL, VT, Div, RHS);
1260   Rem = DAG.getNode(ISD::SUB, DL, VT, LHS, Rem);
1261 
1262   SDValue Res[2] = {
1263     Div,
1264     Rem
1265   };
1266   return DAG.getMergeValues(Res, DL);
1267 }
1268 
1269 void AMDGPUTargetLowering::LowerUDIVREM64(SDValue Op,
1270                                       SelectionDAG &DAG,
1271                                       SmallVectorImpl<SDValue> &Results) const {
1272   assert(Op.getValueType() == MVT::i64);
1273 
1274   SDLoc DL(Op);
1275   EVT VT = Op.getValueType();
1276   EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1277 
1278   SDValue one = DAG.getConstant(1, DL, HalfVT);
1279   SDValue zero = DAG.getConstant(0, DL, HalfVT);
1280 
1281   //HiLo split
1282   SDValue LHS = Op.getOperand(0);
1283   SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, zero);
1284   SDValue LHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, one);
1285 
1286   SDValue RHS = Op.getOperand(1);
1287   SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, zero);
1288   SDValue RHS_Hi = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, one);
1289 
1290   if (VT == MVT::i64 &&
1291     DAG.MaskedValueIsZero(RHS, APInt::getHighBitsSet(64, 32)) &&
1292     DAG.MaskedValueIsZero(LHS, APInt::getHighBitsSet(64, 32))) {
1293 
1294     SDValue Res = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1295                               LHS_Lo, RHS_Lo);
1296 
1297     SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(0), zero});
1298     SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {Res.getValue(1), zero});
1299 
1300     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV));
1301     Results.push_back(DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM));
1302     return;
1303   }
1304 
1305   // Get Speculative values
1306   SDValue DIV_Part = DAG.getNode(ISD::UDIV, DL, HalfVT, LHS_Hi, RHS_Lo);
1307   SDValue REM_Part = DAG.getNode(ISD::UREM, DL, HalfVT, LHS_Hi, RHS_Lo);
1308 
1309   SDValue REM_Lo = DAG.getSelectCC(DL, RHS_Hi, zero, REM_Part, LHS_Hi, ISD::SETEQ);
1310   SDValue REM = DAG.getBuildVector(MVT::v2i32, DL, {REM_Lo, zero});
1311   REM = DAG.getNode(ISD::BITCAST, DL, MVT::i64, REM);
1312 
1313   SDValue DIV_Hi = DAG.getSelectCC(DL, RHS_Hi, zero, DIV_Part, zero, ISD::SETEQ);
1314   SDValue DIV_Lo = zero;
1315 
1316   const unsigned halfBitWidth = HalfVT.getSizeInBits();
1317 
1318   for (unsigned i = 0; i < halfBitWidth; ++i) {
1319     const unsigned bitPos = halfBitWidth - i - 1;
1320     SDValue POS = DAG.getConstant(bitPos, DL, HalfVT);
1321     // Get value of high bit
1322     SDValue HBit = DAG.getNode(ISD::SRL, DL, HalfVT, LHS_Lo, POS);
1323     HBit = DAG.getNode(ISD::AND, DL, HalfVT, HBit, one);
1324     HBit = DAG.getNode(ISD::ZERO_EXTEND, DL, VT, HBit);
1325 
1326     // Shift
1327     REM = DAG.getNode(ISD::SHL, DL, VT, REM, DAG.getConstant(1, DL, VT));
1328     // Add LHS high bit
1329     REM = DAG.getNode(ISD::OR, DL, VT, REM, HBit);
1330 
1331     SDValue BIT = DAG.getConstant(1ULL << bitPos, DL, HalfVT);
1332     SDValue realBIT = DAG.getSelectCC(DL, REM, RHS, BIT, zero, ISD::SETUGE);
1333 
1334     DIV_Lo = DAG.getNode(ISD::OR, DL, HalfVT, DIV_Lo, realBIT);
1335 
1336     // Update REM
1337     SDValue REM_sub = DAG.getNode(ISD::SUB, DL, VT, REM, RHS);
1338     REM = DAG.getSelectCC(DL, REM, RHS, REM_sub, REM, ISD::SETUGE);
1339   }
1340 
1341   SDValue DIV = DAG.getBuildVector(MVT::v2i32, DL, {DIV_Lo, DIV_Hi});
1342   DIV = DAG.getNode(ISD::BITCAST, DL, MVT::i64, DIV);
1343   Results.push_back(DIV);
1344   Results.push_back(REM);
1345 }
1346 
1347 SDValue AMDGPUTargetLowering::LowerUDIVREM(SDValue Op,
1348                                            SelectionDAG &DAG) const {
1349   SDLoc DL(Op);
1350   EVT VT = Op.getValueType();
1351 
1352   if (VT == MVT::i64) {
1353     SmallVector<SDValue, 2> Results;
1354     LowerUDIVREM64(Op, DAG, Results);
1355     return DAG.getMergeValues(Results, DL);
1356   }
1357 
1358   SDValue Num = Op.getOperand(0);
1359   SDValue Den = Op.getOperand(1);
1360 
1361   if (VT == MVT::i32) {
1362     if (DAG.MaskedValueIsZero(Num, APInt::getHighBitsSet(32, 8)) &&
1363         DAG.MaskedValueIsZero(Den, APInt::getHighBitsSet(32, 8))) {
1364       // TODO: We technically could do this for i64, but shouldn't that just be
1365       // handled by something generally reducing 64-bit division on 32-bit
1366       // values to 32-bit?
1367       return LowerDIVREM24(Op, DAG, false);
1368     }
1369   }
1370 
1371   // RCP =  URECIP(Den) = 2^32 / Den + e
1372   // e is rounding error.
1373   SDValue RCP = DAG.getNode(AMDGPUISD::URECIP, DL, VT, Den);
1374 
1375   // RCP_LO = mul(RCP, Den) */
1376   SDValue RCP_LO = DAG.getNode(ISD::MUL, DL, VT, RCP, Den);
1377 
1378   // RCP_HI = mulhu (RCP, Den) */
1379   SDValue RCP_HI = DAG.getNode(ISD::MULHU, DL, VT, RCP, Den);
1380 
1381   // NEG_RCP_LO = -RCP_LO
1382   SDValue NEG_RCP_LO = DAG.getNode(ISD::SUB, DL, VT, DAG.getConstant(0, DL, VT),
1383                                                      RCP_LO);
1384 
1385   // ABS_RCP_LO = (RCP_HI == 0 ? NEG_RCP_LO : RCP_LO)
1386   SDValue ABS_RCP_LO = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1387                                            NEG_RCP_LO, RCP_LO,
1388                                            ISD::SETEQ);
1389   // Calculate the rounding error from the URECIP instruction
1390   // E = mulhu(ABS_RCP_LO, RCP)
1391   SDValue E = DAG.getNode(ISD::MULHU, DL, VT, ABS_RCP_LO, RCP);
1392 
1393   // RCP_A_E = RCP + E
1394   SDValue RCP_A_E = DAG.getNode(ISD::ADD, DL, VT, RCP, E);
1395 
1396   // RCP_S_E = RCP - E
1397   SDValue RCP_S_E = DAG.getNode(ISD::SUB, DL, VT, RCP, E);
1398 
1399   // Tmp0 = (RCP_HI == 0 ? RCP_A_E : RCP_SUB_E)
1400   SDValue Tmp0 = DAG.getSelectCC(DL, RCP_HI, DAG.getConstant(0, DL, VT),
1401                                      RCP_A_E, RCP_S_E,
1402                                      ISD::SETEQ);
1403   // Quotient = mulhu(Tmp0, Num)
1404   SDValue Quotient = DAG.getNode(ISD::MULHU, DL, VT, Tmp0, Num);
1405 
1406   // Num_S_Remainder = Quotient * Den
1407   SDValue Num_S_Remainder = DAG.getNode(ISD::MUL, DL, VT, Quotient, Den);
1408 
1409   // Remainder = Num - Num_S_Remainder
1410   SDValue Remainder = DAG.getNode(ISD::SUB, DL, VT, Num, Num_S_Remainder);
1411 
1412   // Remainder_GE_Den = (Remainder >= Den ? -1 : 0)
1413   SDValue Remainder_GE_Den = DAG.getSelectCC(DL, Remainder, Den,
1414                                                  DAG.getConstant(-1, DL, VT),
1415                                                  DAG.getConstant(0, DL, VT),
1416                                                  ISD::SETUGE);
1417   // Remainder_GE_Zero = (Num >= Num_S_Remainder ? -1 : 0)
1418   SDValue Remainder_GE_Zero = DAG.getSelectCC(DL, Num,
1419                                                   Num_S_Remainder,
1420                                                   DAG.getConstant(-1, DL, VT),
1421                                                   DAG.getConstant(0, DL, VT),
1422                                                   ISD::SETUGE);
1423   // Tmp1 = Remainder_GE_Den & Remainder_GE_Zero
1424   SDValue Tmp1 = DAG.getNode(ISD::AND, DL, VT, Remainder_GE_Den,
1425                                                Remainder_GE_Zero);
1426 
1427   // Calculate Division result:
1428 
1429   // Quotient_A_One = Quotient + 1
1430   SDValue Quotient_A_One = DAG.getNode(ISD::ADD, DL, VT, Quotient,
1431                                        DAG.getConstant(1, DL, VT));
1432 
1433   // Quotient_S_One = Quotient - 1
1434   SDValue Quotient_S_One = DAG.getNode(ISD::SUB, DL, VT, Quotient,
1435                                        DAG.getConstant(1, DL, VT));
1436 
1437   // Div = (Tmp1 == 0 ? Quotient : Quotient_A_One)
1438   SDValue Div = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1439                                      Quotient, Quotient_A_One, ISD::SETEQ);
1440 
1441   // Div = (Remainder_GE_Zero == 0 ? Quotient_S_One : Div)
1442   Div = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1443                             Quotient_S_One, Div, ISD::SETEQ);
1444 
1445   // Calculate Rem result:
1446 
1447   // Remainder_S_Den = Remainder - Den
1448   SDValue Remainder_S_Den = DAG.getNode(ISD::SUB, DL, VT, Remainder, Den);
1449 
1450   // Remainder_A_Den = Remainder + Den
1451   SDValue Remainder_A_Den = DAG.getNode(ISD::ADD, DL, VT, Remainder, Den);
1452 
1453   // Rem = (Tmp1 == 0 ? Remainder : Remainder_S_Den)
1454   SDValue Rem = DAG.getSelectCC(DL, Tmp1, DAG.getConstant(0, DL, VT),
1455                                     Remainder, Remainder_S_Den, ISD::SETEQ);
1456 
1457   // Rem = (Remainder_GE_Zero == 0 ? Remainder_A_Den : Rem)
1458   Rem = DAG.getSelectCC(DL, Remainder_GE_Zero, DAG.getConstant(0, DL, VT),
1459                             Remainder_A_Den, Rem, ISD::SETEQ);
1460   SDValue Ops[2] = {
1461     Div,
1462     Rem
1463   };
1464   return DAG.getMergeValues(Ops, DL);
1465 }
1466 
1467 SDValue AMDGPUTargetLowering::LowerSDIVREM(SDValue Op,
1468                                            SelectionDAG &DAG) const {
1469   SDLoc DL(Op);
1470   EVT VT = Op.getValueType();
1471 
1472   SDValue LHS = Op.getOperand(0);
1473   SDValue RHS = Op.getOperand(1);
1474 
1475   SDValue Zero = DAG.getConstant(0, DL, VT);
1476   SDValue NegOne = DAG.getConstant(-1, DL, VT);
1477 
1478   if (VT == MVT::i32 &&
1479       DAG.ComputeNumSignBits(LHS) > 8 &&
1480       DAG.ComputeNumSignBits(RHS) > 8) {
1481     return LowerDIVREM24(Op, DAG, true);
1482   }
1483   if (VT == MVT::i64 &&
1484       DAG.ComputeNumSignBits(LHS) > 32 &&
1485       DAG.ComputeNumSignBits(RHS) > 32) {
1486     EVT HalfVT = VT.getHalfSizedIntegerVT(*DAG.getContext());
1487 
1488     //HiLo split
1489     SDValue LHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, LHS, Zero);
1490     SDValue RHS_Lo = DAG.getNode(ISD::EXTRACT_ELEMENT, DL, HalfVT, RHS, Zero);
1491     SDValue DIVREM = DAG.getNode(ISD::SDIVREM, DL, DAG.getVTList(HalfVT, HalfVT),
1492                                  LHS_Lo, RHS_Lo);
1493     SDValue Res[2] = {
1494       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(0)),
1495       DAG.getNode(ISD::SIGN_EXTEND, DL, VT, DIVREM.getValue(1))
1496     };
1497     return DAG.getMergeValues(Res, DL);
1498   }
1499 
1500   SDValue LHSign = DAG.getSelectCC(DL, LHS, Zero, NegOne, Zero, ISD::SETLT);
1501   SDValue RHSign = DAG.getSelectCC(DL, RHS, Zero, NegOne, Zero, ISD::SETLT);
1502   SDValue DSign = DAG.getNode(ISD::XOR, DL, VT, LHSign, RHSign);
1503   SDValue RSign = LHSign; // Remainder sign is the same as LHS
1504 
1505   LHS = DAG.getNode(ISD::ADD, DL, VT, LHS, LHSign);
1506   RHS = DAG.getNode(ISD::ADD, DL, VT, RHS, RHSign);
1507 
1508   LHS = DAG.getNode(ISD::XOR, DL, VT, LHS, LHSign);
1509   RHS = DAG.getNode(ISD::XOR, DL, VT, RHS, RHSign);
1510 
1511   SDValue Div = DAG.getNode(ISD::UDIVREM, DL, DAG.getVTList(VT, VT), LHS, RHS);
1512   SDValue Rem = Div.getValue(1);
1513 
1514   Div = DAG.getNode(ISD::XOR, DL, VT, Div, DSign);
1515   Rem = DAG.getNode(ISD::XOR, DL, VT, Rem, RSign);
1516 
1517   Div = DAG.getNode(ISD::SUB, DL, VT, Div, DSign);
1518   Rem = DAG.getNode(ISD::SUB, DL, VT, Rem, RSign);
1519 
1520   SDValue Res[2] = {
1521     Div,
1522     Rem
1523   };
1524   return DAG.getMergeValues(Res, DL);
1525 }
1526 
1527 // (frem x, y) -> (fsub x, (fmul (ftrunc (fdiv x, y)), y))
1528 SDValue AMDGPUTargetLowering::LowerFREM(SDValue Op, SelectionDAG &DAG) const {
1529   SDLoc SL(Op);
1530   EVT VT = Op.getValueType();
1531   SDValue X = Op.getOperand(0);
1532   SDValue Y = Op.getOperand(1);
1533 
1534   // TODO: Should this propagate fast-math-flags?
1535 
1536   SDValue Div = DAG.getNode(ISD::FDIV, SL, VT, X, Y);
1537   SDValue Floor = DAG.getNode(ISD::FTRUNC, SL, VT, Div);
1538   SDValue Mul = DAG.getNode(ISD::FMUL, SL, VT, Floor, Y);
1539 
1540   return DAG.getNode(ISD::FSUB, SL, VT, X, Mul);
1541 }
1542 
1543 SDValue AMDGPUTargetLowering::LowerFCEIL(SDValue Op, SelectionDAG &DAG) const {
1544   SDLoc SL(Op);
1545   SDValue Src = Op.getOperand(0);
1546 
1547   // result = trunc(src)
1548   // if (src > 0.0 && src != result)
1549   //   result += 1.0
1550 
1551   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
1552 
1553   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
1554   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f64);
1555 
1556   EVT SetCCVT =
1557       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
1558 
1559   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOGT);
1560   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
1561   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
1562 
1563   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, One, Zero);
1564   // TODO: Should this propagate fast-math-flags?
1565   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
1566 }
1567 
1568 static SDValue extractF64Exponent(SDValue Hi, SDLoc SL, SelectionDAG &DAG) {
1569   const unsigned FractBits = 52;
1570   const unsigned ExpBits = 11;
1571 
1572   SDValue ExpPart = DAG.getNode(AMDGPUISD::BFE_U32, SL, MVT::i32,
1573                                 Hi,
1574                                 DAG.getConstant(FractBits - 32, SL, MVT::i32),
1575                                 DAG.getConstant(ExpBits, SL, MVT::i32));
1576   SDValue Exp = DAG.getNode(ISD::SUB, SL, MVT::i32, ExpPart,
1577                             DAG.getConstant(1023, SL, MVT::i32));
1578 
1579   return Exp;
1580 }
1581 
1582 SDValue AMDGPUTargetLowering::LowerFTRUNC(SDValue Op, SelectionDAG &DAG) const {
1583   SDLoc SL(Op);
1584   SDValue Src = Op.getOperand(0);
1585 
1586   assert(Op.getValueType() == MVT::f64);
1587 
1588   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1589   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1590 
1591   SDValue VecSrc = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
1592 
1593   // Extract the upper half, since this is where we will find the sign and
1594   // exponent.
1595   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, VecSrc, One);
1596 
1597   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
1598 
1599   const unsigned FractBits = 52;
1600 
1601   // Extract the sign bit.
1602   const SDValue SignBitMask = DAG.getConstant(UINT32_C(1) << 31, SL, MVT::i32);
1603   SDValue SignBit = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, SignBitMask);
1604 
1605   // Extend back to to 64-bits.
1606   SDValue SignBit64 = DAG.getBuildVector(MVT::v2i32, SL, {Zero, SignBit});
1607   SignBit64 = DAG.getNode(ISD::BITCAST, SL, MVT::i64, SignBit64);
1608 
1609   SDValue BcInt = DAG.getNode(ISD::BITCAST, SL, MVT::i64, Src);
1610   const SDValue FractMask
1611     = DAG.getConstant((UINT64_C(1) << FractBits) - 1, SL, MVT::i64);
1612 
1613   SDValue Shr = DAG.getNode(ISD::SRA, SL, MVT::i64, FractMask, Exp);
1614   SDValue Not = DAG.getNOT(SL, Shr, MVT::i64);
1615   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, BcInt, Not);
1616 
1617   EVT SetCCVT =
1618       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
1619 
1620   const SDValue FiftyOne = DAG.getConstant(FractBits - 1, SL, MVT::i32);
1621 
1622   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
1623   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
1624 
1625   SDValue Tmp1 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpLt0, SignBit64, Tmp0);
1626   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, ExpGt51, BcInt, Tmp1);
1627 
1628   return DAG.getNode(ISD::BITCAST, SL, MVT::f64, Tmp2);
1629 }
1630 
1631 SDValue AMDGPUTargetLowering::LowerFRINT(SDValue Op, SelectionDAG &DAG) const {
1632   SDLoc SL(Op);
1633   SDValue Src = Op.getOperand(0);
1634 
1635   assert(Op.getValueType() == MVT::f64);
1636 
1637   APFloat C1Val(APFloat::IEEEdouble, "0x1.0p+52");
1638   SDValue C1 = DAG.getConstantFP(C1Val, SL, MVT::f64);
1639   SDValue CopySign = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, C1, Src);
1640 
1641   // TODO: Should this propagate fast-math-flags?
1642 
1643   SDValue Tmp1 = DAG.getNode(ISD::FADD, SL, MVT::f64, Src, CopySign);
1644   SDValue Tmp2 = DAG.getNode(ISD::FSUB, SL, MVT::f64, Tmp1, CopySign);
1645 
1646   SDValue Fabs = DAG.getNode(ISD::FABS, SL, MVT::f64, Src);
1647 
1648   APFloat C2Val(APFloat::IEEEdouble, "0x1.fffffffffffffp+51");
1649   SDValue C2 = DAG.getConstantFP(C2Val, SL, MVT::f64);
1650 
1651   EVT SetCCVT =
1652       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
1653   SDValue Cond = DAG.getSetCC(SL, SetCCVT, Fabs, C2, ISD::SETOGT);
1654 
1655   return DAG.getSelect(SL, MVT::f64, Cond, Src, Tmp2);
1656 }
1657 
1658 SDValue AMDGPUTargetLowering::LowerFNEARBYINT(SDValue Op, SelectionDAG &DAG) const {
1659   // FNEARBYINT and FRINT are the same, except in their handling of FP
1660   // exceptions. Those aren't really meaningful for us, and OpenCL only has
1661   // rint, so just treat them as equivalent.
1662   return DAG.getNode(ISD::FRINT, SDLoc(Op), Op.getValueType(), Op.getOperand(0));
1663 }
1664 
1665 // XXX - May require not supporting f32 denormals?
1666 SDValue AMDGPUTargetLowering::LowerFROUND32(SDValue Op, SelectionDAG &DAG) const {
1667   SDLoc SL(Op);
1668   SDValue X = Op.getOperand(0);
1669 
1670   SDValue T = DAG.getNode(ISD::FTRUNC, SL, MVT::f32, X);
1671 
1672   // TODO: Should this propagate fast-math-flags?
1673 
1674   SDValue Diff = DAG.getNode(ISD::FSUB, SL, MVT::f32, X, T);
1675 
1676   SDValue AbsDiff = DAG.getNode(ISD::FABS, SL, MVT::f32, Diff);
1677 
1678   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f32);
1679   const SDValue One = DAG.getConstantFP(1.0, SL, MVT::f32);
1680   const SDValue Half = DAG.getConstantFP(0.5, SL, MVT::f32);
1681 
1682   SDValue SignOne = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f32, One, X);
1683 
1684   EVT SetCCVT =
1685       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f32);
1686 
1687   SDValue Cmp = DAG.getSetCC(SL, SetCCVT, AbsDiff, Half, ISD::SETOGE);
1688 
1689   SDValue Sel = DAG.getNode(ISD::SELECT, SL, MVT::f32, Cmp, SignOne, Zero);
1690 
1691   return DAG.getNode(ISD::FADD, SL, MVT::f32, T, Sel);
1692 }
1693 
1694 SDValue AMDGPUTargetLowering::LowerFROUND64(SDValue Op, SelectionDAG &DAG) const {
1695   SDLoc SL(Op);
1696   SDValue X = Op.getOperand(0);
1697 
1698   SDValue L = DAG.getNode(ISD::BITCAST, SL, MVT::i64, X);
1699 
1700   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1701   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1702   const SDValue NegOne = DAG.getConstant(-1, SL, MVT::i32);
1703   const SDValue FiftyOne = DAG.getConstant(51, SL, MVT::i32);
1704   EVT SetCCVT =
1705       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::i32);
1706 
1707   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, X);
1708 
1709   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC, One);
1710 
1711   SDValue Exp = extractF64Exponent(Hi, SL, DAG);
1712 
1713   const SDValue Mask = DAG.getConstant(INT64_C(0x000fffffffffffff), SL,
1714                                        MVT::i64);
1715 
1716   SDValue M = DAG.getNode(ISD::SRA, SL, MVT::i64, Mask, Exp);
1717   SDValue D = DAG.getNode(ISD::SRA, SL, MVT::i64,
1718                           DAG.getConstant(INT64_C(0x0008000000000000), SL,
1719                                           MVT::i64),
1720                           Exp);
1721 
1722   SDValue Tmp0 = DAG.getNode(ISD::AND, SL, MVT::i64, L, M);
1723   SDValue Tmp1 = DAG.getSetCC(SL, SetCCVT,
1724                               DAG.getConstant(0, SL, MVT::i64), Tmp0,
1725                               ISD::SETNE);
1726 
1727   SDValue Tmp2 = DAG.getNode(ISD::SELECT, SL, MVT::i64, Tmp1,
1728                              D, DAG.getConstant(0, SL, MVT::i64));
1729   SDValue K = DAG.getNode(ISD::ADD, SL, MVT::i64, L, Tmp2);
1730 
1731   K = DAG.getNode(ISD::AND, SL, MVT::i64, K, DAG.getNOT(SL, M, MVT::i64));
1732   K = DAG.getNode(ISD::BITCAST, SL, MVT::f64, K);
1733 
1734   SDValue ExpLt0 = DAG.getSetCC(SL, SetCCVT, Exp, Zero, ISD::SETLT);
1735   SDValue ExpGt51 = DAG.getSetCC(SL, SetCCVT, Exp, FiftyOne, ISD::SETGT);
1736   SDValue ExpEqNegOne = DAG.getSetCC(SL, SetCCVT, NegOne, Exp, ISD::SETEQ);
1737 
1738   SDValue Mag = DAG.getNode(ISD::SELECT, SL, MVT::f64,
1739                             ExpEqNegOne,
1740                             DAG.getConstantFP(1.0, SL, MVT::f64),
1741                             DAG.getConstantFP(0.0, SL, MVT::f64));
1742 
1743   SDValue S = DAG.getNode(ISD::FCOPYSIGN, SL, MVT::f64, Mag, X);
1744 
1745   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpLt0, S, K);
1746   K = DAG.getNode(ISD::SELECT, SL, MVT::f64, ExpGt51, X, K);
1747 
1748   return K;
1749 }
1750 
1751 SDValue AMDGPUTargetLowering::LowerFROUND(SDValue Op, SelectionDAG &DAG) const {
1752   EVT VT = Op.getValueType();
1753 
1754   if (VT == MVT::f32)
1755     return LowerFROUND32(Op, DAG);
1756 
1757   if (VT == MVT::f64)
1758     return LowerFROUND64(Op, DAG);
1759 
1760   llvm_unreachable("unhandled type");
1761 }
1762 
1763 SDValue AMDGPUTargetLowering::LowerFFLOOR(SDValue Op, SelectionDAG &DAG) const {
1764   SDLoc SL(Op);
1765   SDValue Src = Op.getOperand(0);
1766 
1767   // result = trunc(src);
1768   // if (src < 0.0 && src != result)
1769   //   result += -1.0.
1770 
1771   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
1772 
1773   const SDValue Zero = DAG.getConstantFP(0.0, SL, MVT::f64);
1774   const SDValue NegOne = DAG.getConstantFP(-1.0, SL, MVT::f64);
1775 
1776   EVT SetCCVT =
1777       getSetCCResultType(DAG.getDataLayout(), *DAG.getContext(), MVT::f64);
1778 
1779   SDValue Lt0 = DAG.getSetCC(SL, SetCCVT, Src, Zero, ISD::SETOLT);
1780   SDValue NeTrunc = DAG.getSetCC(SL, SetCCVT, Src, Trunc, ISD::SETONE);
1781   SDValue And = DAG.getNode(ISD::AND, SL, SetCCVT, Lt0, NeTrunc);
1782 
1783   SDValue Add = DAG.getNode(ISD::SELECT, SL, MVT::f64, And, NegOne, Zero);
1784   // TODO: Should this propagate fast-math-flags?
1785   return DAG.getNode(ISD::FADD, SL, MVT::f64, Trunc, Add);
1786 }
1787 
1788 SDValue AMDGPUTargetLowering::LowerCTLZ(SDValue Op, SelectionDAG &DAG) const {
1789   SDLoc SL(Op);
1790   SDValue Src = Op.getOperand(0);
1791   bool ZeroUndef = Op.getOpcode() == ISD::CTLZ_ZERO_UNDEF;
1792 
1793   if (ZeroUndef && Src.getValueType() == MVT::i32)
1794     return DAG.getNode(AMDGPUISD::FFBH_U32, SL, MVT::i32, Src);
1795 
1796   SDValue Vec = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
1797 
1798   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
1799   const SDValue One = DAG.getConstant(1, SL, MVT::i32);
1800 
1801   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, Zero);
1802   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, Vec, One);
1803 
1804   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
1805                                    *DAG.getContext(), MVT::i32);
1806 
1807   SDValue Hi0 = DAG.getSetCC(SL, SetCCVT, Hi, Zero, ISD::SETEQ);
1808 
1809   SDValue CtlzLo = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i32, Lo);
1810   SDValue CtlzHi = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i32, Hi);
1811 
1812   const SDValue Bits32 = DAG.getConstant(32, SL, MVT::i32);
1813   SDValue Add = DAG.getNode(ISD::ADD, SL, MVT::i32, CtlzLo, Bits32);
1814 
1815   // ctlz(x) = hi_32(x) == 0 ? ctlz(lo_32(x)) + 32 : ctlz(hi_32(x))
1816   SDValue NewCtlz = DAG.getNode(ISD::SELECT, SL, MVT::i32, Hi0, Add, CtlzHi);
1817 
1818   if (!ZeroUndef) {
1819     // Test if the full 64-bit input is zero.
1820 
1821     // FIXME: DAG combines turn what should be an s_and_b64 into a v_or_b32,
1822     // which we probably don't want.
1823     SDValue Lo0 = DAG.getSetCC(SL, SetCCVT, Lo, Zero, ISD::SETEQ);
1824     SDValue SrcIsZero = DAG.getNode(ISD::AND, SL, SetCCVT, Lo0, Hi0);
1825 
1826     // TODO: If i64 setcc is half rate, it can result in 1 fewer instruction
1827     // with the same cycles, otherwise it is slower.
1828     // SDValue SrcIsZero = DAG.getSetCC(SL, SetCCVT, Src,
1829     // DAG.getConstant(0, SL, MVT::i64), ISD::SETEQ);
1830 
1831     const SDValue Bits32 = DAG.getConstant(64, SL, MVT::i32);
1832 
1833     // The instruction returns -1 for 0 input, but the defined intrinsic
1834     // behavior is to return the number of bits.
1835     NewCtlz = DAG.getNode(ISD::SELECT, SL, MVT::i32,
1836                           SrcIsZero, Bits32, NewCtlz);
1837   }
1838 
1839   return DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i64, NewCtlz);
1840 }
1841 
1842 SDValue AMDGPUTargetLowering::LowerINT_TO_FP32(SDValue Op, SelectionDAG &DAG,
1843                                                bool Signed) const {
1844   // Unsigned
1845   // cul2f(ulong u)
1846   //{
1847   //  uint lz = clz(u);
1848   //  uint e = (u != 0) ? 127U + 63U - lz : 0;
1849   //  u = (u << lz) & 0x7fffffffffffffffUL;
1850   //  ulong t = u & 0xffffffffffUL;
1851   //  uint v = (e << 23) | (uint)(u >> 40);
1852   //  uint r = t > 0x8000000000UL ? 1U : (t == 0x8000000000UL ? v & 1U : 0U);
1853   //  return as_float(v + r);
1854   //}
1855   // Signed
1856   // cl2f(long l)
1857   //{
1858   //  long s = l >> 63;
1859   //  float r = cul2f((l + s) ^ s);
1860   //  return s ? -r : r;
1861   //}
1862 
1863   SDLoc SL(Op);
1864   SDValue Src = Op.getOperand(0);
1865   SDValue L = Src;
1866 
1867   SDValue S;
1868   if (Signed) {
1869     const SDValue SignBit = DAG.getConstant(63, SL, MVT::i64);
1870     S = DAG.getNode(ISD::SRA, SL, MVT::i64, L, SignBit);
1871 
1872     SDValue LPlusS = DAG.getNode(ISD::ADD, SL, MVT::i64, L, S);
1873     L = DAG.getNode(ISD::XOR, SL, MVT::i64, LPlusS, S);
1874   }
1875 
1876   EVT SetCCVT = getSetCCResultType(DAG.getDataLayout(),
1877                                    *DAG.getContext(), MVT::f32);
1878 
1879 
1880   SDValue ZeroI32 = DAG.getConstant(0, SL, MVT::i32);
1881   SDValue ZeroI64 = DAG.getConstant(0, SL, MVT::i64);
1882   SDValue LZ = DAG.getNode(ISD::CTLZ_ZERO_UNDEF, SL, MVT::i64, L);
1883   LZ = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LZ);
1884 
1885   SDValue K = DAG.getConstant(127U + 63U, SL, MVT::i32);
1886   SDValue E = DAG.getSelect(SL, MVT::i32,
1887     DAG.getSetCC(SL, SetCCVT, L, ZeroI64, ISD::SETNE),
1888     DAG.getNode(ISD::SUB, SL, MVT::i32, K, LZ),
1889     ZeroI32);
1890 
1891   SDValue U = DAG.getNode(ISD::AND, SL, MVT::i64,
1892     DAG.getNode(ISD::SHL, SL, MVT::i64, L, LZ),
1893     DAG.getConstant((-1ULL) >> 1, SL, MVT::i64));
1894 
1895   SDValue T = DAG.getNode(ISD::AND, SL, MVT::i64, U,
1896                           DAG.getConstant(0xffffffffffULL, SL, MVT::i64));
1897 
1898   SDValue UShl = DAG.getNode(ISD::SRL, SL, MVT::i64,
1899                              U, DAG.getConstant(40, SL, MVT::i64));
1900 
1901   SDValue V = DAG.getNode(ISD::OR, SL, MVT::i32,
1902     DAG.getNode(ISD::SHL, SL, MVT::i32, E, DAG.getConstant(23, SL, MVT::i32)),
1903     DAG.getNode(ISD::TRUNCATE, SL, MVT::i32,  UShl));
1904 
1905   SDValue C = DAG.getConstant(0x8000000000ULL, SL, MVT::i64);
1906   SDValue RCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETUGT);
1907   SDValue TCmp = DAG.getSetCC(SL, SetCCVT, T, C, ISD::SETEQ);
1908 
1909   SDValue One = DAG.getConstant(1, SL, MVT::i32);
1910 
1911   SDValue VTrunc1 = DAG.getNode(ISD::AND, SL, MVT::i32, V, One);
1912 
1913   SDValue R = DAG.getSelect(SL, MVT::i32,
1914     RCmp,
1915     One,
1916     DAG.getSelect(SL, MVT::i32, TCmp, VTrunc1, ZeroI32));
1917   R = DAG.getNode(ISD::ADD, SL, MVT::i32, V, R);
1918   R = DAG.getNode(ISD::BITCAST, SL, MVT::f32, R);
1919 
1920   if (!Signed)
1921     return R;
1922 
1923   SDValue RNeg = DAG.getNode(ISD::FNEG, SL, MVT::f32, R);
1924   return DAG.getSelect(SL, MVT::f32, DAG.getSExtOrTrunc(S, SL, SetCCVT), RNeg, R);
1925 }
1926 
1927 SDValue AMDGPUTargetLowering::LowerINT_TO_FP64(SDValue Op, SelectionDAG &DAG,
1928                                                bool Signed) const {
1929   SDLoc SL(Op);
1930   SDValue Src = Op.getOperand(0);
1931 
1932   SDValue BC = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, Src);
1933 
1934   SDValue Lo = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
1935                            DAG.getConstant(0, SL, MVT::i32));
1936   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32, BC,
1937                            DAG.getConstant(1, SL, MVT::i32));
1938 
1939   SDValue CvtHi = DAG.getNode(Signed ? ISD::SINT_TO_FP : ISD::UINT_TO_FP,
1940                               SL, MVT::f64, Hi);
1941 
1942   SDValue CvtLo = DAG.getNode(ISD::UINT_TO_FP, SL, MVT::f64, Lo);
1943 
1944   SDValue LdExp = DAG.getNode(AMDGPUISD::LDEXP, SL, MVT::f64, CvtHi,
1945                               DAG.getConstant(32, SL, MVT::i32));
1946   // TODO: Should this propagate fast-math-flags?
1947   return DAG.getNode(ISD::FADD, SL, MVT::f64, LdExp, CvtLo);
1948 }
1949 
1950 SDValue AMDGPUTargetLowering::LowerUINT_TO_FP(SDValue Op,
1951                                                SelectionDAG &DAG) const {
1952   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
1953          "operation should be legal");
1954 
1955   EVT DestVT = Op.getValueType();
1956   if (DestVT == MVT::f64)
1957     return LowerINT_TO_FP64(Op, DAG, false);
1958 
1959   if (DestVT == MVT::f32)
1960     return LowerINT_TO_FP32(Op, DAG, false);
1961 
1962   return SDValue();
1963 }
1964 
1965 SDValue AMDGPUTargetLowering::LowerSINT_TO_FP(SDValue Op,
1966                                               SelectionDAG &DAG) const {
1967   assert(Op.getOperand(0).getValueType() == MVT::i64 &&
1968          "operation should be legal");
1969 
1970   EVT DestVT = Op.getValueType();
1971   if (DestVT == MVT::f32)
1972     return LowerINT_TO_FP32(Op, DAG, true);
1973 
1974   if (DestVT == MVT::f64)
1975     return LowerINT_TO_FP64(Op, DAG, true);
1976 
1977   return SDValue();
1978 }
1979 
1980 SDValue AMDGPUTargetLowering::LowerFP64_TO_INT(SDValue Op, SelectionDAG &DAG,
1981                                                bool Signed) const {
1982   SDLoc SL(Op);
1983 
1984   SDValue Src = Op.getOperand(0);
1985 
1986   SDValue Trunc = DAG.getNode(ISD::FTRUNC, SL, MVT::f64, Src);
1987 
1988   SDValue K0 = DAG.getConstantFP(BitsToDouble(UINT64_C(0x3df0000000000000)), SL,
1989                                  MVT::f64);
1990   SDValue K1 = DAG.getConstantFP(BitsToDouble(UINT64_C(0xc1f0000000000000)), SL,
1991                                  MVT::f64);
1992   // TODO: Should this propagate fast-math-flags?
1993   SDValue Mul = DAG.getNode(ISD::FMUL, SL, MVT::f64, Trunc, K0);
1994 
1995   SDValue FloorMul = DAG.getNode(ISD::FFLOOR, SL, MVT::f64, Mul);
1996 
1997 
1998   SDValue Fma = DAG.getNode(ISD::FMA, SL, MVT::f64, FloorMul, K1, Trunc);
1999 
2000   SDValue Hi = DAG.getNode(Signed ? ISD::FP_TO_SINT : ISD::FP_TO_UINT, SL,
2001                            MVT::i32, FloorMul);
2002   SDValue Lo = DAG.getNode(ISD::FP_TO_UINT, SL, MVT::i32, Fma);
2003 
2004   SDValue Result = DAG.getBuildVector(MVT::v2i32, SL, {Lo, Hi});
2005 
2006   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Result);
2007 }
2008 
2009 SDValue AMDGPUTargetLowering::LowerFP_TO_SINT(SDValue Op,
2010                                               SelectionDAG &DAG) const {
2011   SDValue Src = Op.getOperand(0);
2012 
2013   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2014     return LowerFP64_TO_INT(Op, DAG, true);
2015 
2016   return SDValue();
2017 }
2018 
2019 SDValue AMDGPUTargetLowering::LowerFP_TO_UINT(SDValue Op,
2020                                               SelectionDAG &DAG) const {
2021   SDValue Src = Op.getOperand(0);
2022 
2023   if (Op.getValueType() == MVT::i64 && Src.getValueType() == MVT::f64)
2024     return LowerFP64_TO_INT(Op, DAG, false);
2025 
2026   return SDValue();
2027 }
2028 
2029 SDValue AMDGPUTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op,
2030                                                      SelectionDAG &DAG) const {
2031   EVT ExtraVT = cast<VTSDNode>(Op.getOperand(1))->getVT();
2032   MVT VT = Op.getSimpleValueType();
2033   MVT ScalarVT = VT.getScalarType();
2034 
2035   if (!VT.isVector())
2036     return SDValue();
2037 
2038   SDValue Src = Op.getOperand(0);
2039   SDLoc DL(Op);
2040 
2041   // TODO: Don't scalarize on Evergreen?
2042   unsigned NElts = VT.getVectorNumElements();
2043   SmallVector<SDValue, 8> Args;
2044   DAG.ExtractVectorElements(Src, Args, 0, NElts);
2045 
2046   SDValue VTOp = DAG.getValueType(ExtraVT.getScalarType());
2047   for (unsigned I = 0; I < NElts; ++I)
2048     Args[I] = DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, ScalarVT, Args[I], VTOp);
2049 
2050   return DAG.getBuildVector(VT, DL, Args);
2051 }
2052 
2053 //===----------------------------------------------------------------------===//
2054 // Custom DAG optimizations
2055 //===----------------------------------------------------------------------===//
2056 
2057 static bool isU24(SDValue Op, SelectionDAG &DAG) {
2058   APInt KnownZero, KnownOne;
2059   EVT VT = Op.getValueType();
2060   DAG.computeKnownBits(Op, KnownZero, KnownOne);
2061 
2062   return (VT.getSizeInBits() - KnownZero.countLeadingOnes()) <= 24;
2063 }
2064 
2065 static bool isI24(SDValue Op, SelectionDAG &DAG) {
2066   EVT VT = Op.getValueType();
2067 
2068   // In order for this to be a signed 24-bit value, bit 23, must
2069   // be a sign bit.
2070   return VT.getSizeInBits() >= 24 && // Types less than 24-bit should be treated
2071                                      // as unsigned 24-bit values.
2072          (VT.getSizeInBits() - DAG.ComputeNumSignBits(Op)) < 24;
2073 }
2074 
2075 static void simplifyI24(SDValue Op, TargetLowering::DAGCombinerInfo &DCI) {
2076 
2077   SelectionDAG &DAG = DCI.DAG;
2078   const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2079   EVT VT = Op.getValueType();
2080 
2081   APInt Demanded = APInt::getLowBitsSet(VT.getSizeInBits(), 24);
2082   APInt KnownZero, KnownOne;
2083   TargetLowering::TargetLoweringOpt TLO(DAG, true, true);
2084   if (TLI.SimplifyDemandedBits(Op, Demanded, KnownZero, KnownOne, TLO))
2085     DCI.CommitTargetLoweringOpt(TLO);
2086 }
2087 
2088 template <typename IntTy>
2089 static SDValue constantFoldBFE(SelectionDAG &DAG, IntTy Src0,
2090                                uint32_t Offset, uint32_t Width, SDLoc DL) {
2091   if (Width + Offset < 32) {
2092     uint32_t Shl = static_cast<uint32_t>(Src0) << (32 - Offset - Width);
2093     IntTy Result = static_cast<IntTy>(Shl) >> (32 - Width);
2094     return DAG.getConstant(Result, DL, MVT::i32);
2095   }
2096 
2097   return DAG.getConstant(Src0 >> Offset, DL, MVT::i32);
2098 }
2099 
2100 static bool usesAllNormalStores(SDNode *LoadVal) {
2101   for (SDNode::use_iterator I = LoadVal->use_begin(); !I.atEnd(); ++I) {
2102     if (!ISD::isNormalStore(*I))
2103       return false;
2104   }
2105 
2106   return true;
2107 }
2108 
2109 // If we have a copy of an illegal type, replace it with a load / store of an
2110 // equivalently sized legal type. This avoids intermediate bit pack / unpack
2111 // instructions emitted when handling extloads and truncstores. Ideally we could
2112 // recognize the pack / unpack pattern to eliminate it.
2113 SDValue AMDGPUTargetLowering::performStoreCombine(SDNode *N,
2114                                                   DAGCombinerInfo &DCI) const {
2115   if (!DCI.isBeforeLegalize())
2116     return SDValue();
2117 
2118   StoreSDNode *SN = cast<StoreSDNode>(N);
2119   SDValue Value = SN->getValue();
2120   EVT VT = Value.getValueType();
2121 
2122   if (isTypeLegal(VT) || SN->isVolatile() ||
2123       !ISD::isNormalLoad(Value.getNode()) || VT.getSizeInBits() < 8)
2124     return SDValue();
2125 
2126   LoadSDNode *LoadVal = cast<LoadSDNode>(Value);
2127   if (LoadVal->isVolatile() || !usesAllNormalStores(LoadVal))
2128     return SDValue();
2129 
2130   EVT MemVT = LoadVal->getMemoryVT();
2131 
2132   SDLoc SL(N);
2133   SelectionDAG &DAG = DCI.DAG;
2134   EVT LoadVT = getEquivalentMemType(*DAG.getContext(), MemVT);
2135 
2136   SDValue NewLoad = DAG.getLoad(ISD::UNINDEXED, ISD::NON_EXTLOAD,
2137                                 LoadVT, SL,
2138                                 LoadVal->getChain(),
2139                                 LoadVal->getBasePtr(),
2140                                 LoadVal->getOffset(),
2141                                 LoadVT,
2142                                 LoadVal->getMemOperand());
2143 
2144   SDValue CastLoad = DAG.getNode(ISD::BITCAST, SL, VT, NewLoad.getValue(0));
2145   DCI.CombineTo(LoadVal, CastLoad, NewLoad.getValue(1), false);
2146 
2147   return DAG.getStore(SN->getChain(), SL, NewLoad,
2148                       SN->getBasePtr(), SN->getMemOperand());
2149 }
2150 
2151 // TODO: Should repeat for other bit ops.
2152 SDValue AMDGPUTargetLowering::performAndCombine(SDNode *N,
2153                                                 DAGCombinerInfo &DCI) const {
2154   if (N->getValueType(0) != MVT::i64)
2155     return SDValue();
2156 
2157   // Break up 64-bit and of a constant into two 32-bit ands. This will typically
2158   // happen anyway for a VALU 64-bit and. This exposes other 32-bit integer
2159   // combine opportunities since most 64-bit operations are decomposed this way.
2160   // TODO: We won't want this for SALU especially if it is an inline immediate.
2161   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2162   if (!RHS)
2163     return SDValue();
2164 
2165   uint64_t Val = RHS->getZExtValue();
2166   if (Lo_32(Val) != 0 && Hi_32(Val) != 0 && !RHS->hasOneUse()) {
2167     // If either half of the constant is 0, this is really a 32-bit and, so
2168     // split it. If we can re-use the full materialized constant, keep it.
2169     return SDValue();
2170   }
2171 
2172   SDLoc SL(N);
2173   SelectionDAG &DAG = DCI.DAG;
2174 
2175   SDValue Lo, Hi;
2176   std::tie(Lo, Hi) = split64BitValue(N->getOperand(0), DAG);
2177 
2178   SDValue LoRHS = DAG.getConstant(Lo_32(Val), SL, MVT::i32);
2179   SDValue HiRHS = DAG.getConstant(Hi_32(Val), SL, MVT::i32);
2180 
2181   SDValue LoAnd = DAG.getNode(ISD::AND, SL, MVT::i32, Lo, LoRHS);
2182   SDValue HiAnd = DAG.getNode(ISD::AND, SL, MVT::i32, Hi, HiRHS);
2183 
2184   // Re-visit the ands. It's possible we eliminated one of them and it could
2185   // simplify the vector.
2186   DCI.AddToWorklist(Lo.getNode());
2187   DCI.AddToWorklist(Hi.getNode());
2188 
2189   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {LoAnd, HiAnd});
2190   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2191 }
2192 
2193 SDValue AMDGPUTargetLowering::performShlCombine(SDNode *N,
2194                                                 DAGCombinerInfo &DCI) const {
2195   if (N->getValueType(0) != MVT::i64)
2196     return SDValue();
2197 
2198   // i64 (shl x, C) -> (build_pair 0, (shl x, C -32))
2199 
2200   // On some subtargets, 64-bit shift is a quarter rate instruction. In the
2201   // common case, splitting this into a move and a 32-bit shift is faster and
2202   // the same code size.
2203   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2204   if (!RHS)
2205     return SDValue();
2206 
2207   unsigned RHSVal = RHS->getZExtValue();
2208   if (RHSVal < 32)
2209     return SDValue();
2210 
2211   SDValue LHS = N->getOperand(0);
2212 
2213   SDLoc SL(N);
2214   SelectionDAG &DAG = DCI.DAG;
2215 
2216   SDValue ShiftAmt = DAG.getConstant(RHSVal - 32, SL, MVT::i32);
2217 
2218   SDValue Lo = DAG.getNode(ISD::TRUNCATE, SL, MVT::i32, LHS);
2219   SDValue NewShift = DAG.getNode(ISD::SHL, SL, MVT::i32, Lo, ShiftAmt);
2220 
2221   const SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2222 
2223   SDValue Vec = DAG.getBuildVector(MVT::v2i32, SL, {Zero, NewShift});
2224   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, Vec);
2225 }
2226 
2227 SDValue AMDGPUTargetLowering::performSraCombine(SDNode *N,
2228                                                 DAGCombinerInfo &DCI) const {
2229   if (N->getValueType(0) != MVT::i64)
2230     return SDValue();
2231 
2232   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2233   if (!RHS)
2234     return SDValue();
2235 
2236   SelectionDAG &DAG = DCI.DAG;
2237   SDLoc SL(N);
2238   unsigned RHSVal = RHS->getZExtValue();
2239 
2240   // (sra i64:x, 32) -> build_pair x, (sra hi_32(x), 31)
2241   if (RHSVal == 32) {
2242     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
2243     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
2244                                    DAG.getConstant(31, SL, MVT::i32));
2245 
2246     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {Hi, NewShift});
2247     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
2248   }
2249 
2250   // (sra i64:x, 63) -> build_pair (sra hi_32(x), 31), (sra hi_32(x), 31)
2251   if (RHSVal == 63) {
2252     SDValue Hi = getHiHalf64(N->getOperand(0), DAG);
2253     SDValue NewShift = DAG.getNode(ISD::SRA, SL, MVT::i32, Hi,
2254                                    DAG.getConstant(31, SL, MVT::i32));
2255     SDValue BuildVec = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, NewShift});
2256     return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildVec);
2257   }
2258 
2259   return SDValue();
2260 }
2261 
2262 SDValue AMDGPUTargetLowering::performSrlCombine(SDNode *N,
2263                                                 DAGCombinerInfo &DCI) const {
2264   if (N->getValueType(0) != MVT::i64)
2265     return SDValue();
2266 
2267   const ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N->getOperand(1));
2268   if (!RHS)
2269     return SDValue();
2270 
2271   unsigned ShiftAmt = RHS->getZExtValue();
2272   if (ShiftAmt < 32)
2273     return SDValue();
2274 
2275   // srl i64:x, C for C >= 32
2276   // =>
2277   //   build_pair (srl hi_32(x), C - 32), 0
2278 
2279   SelectionDAG &DAG = DCI.DAG;
2280   SDLoc SL(N);
2281 
2282   SDValue One = DAG.getConstant(1, SL, MVT::i32);
2283   SDValue Zero = DAG.getConstant(0, SL, MVT::i32);
2284 
2285   SDValue VecOp = DAG.getNode(ISD::BITCAST, SL, MVT::v2i32, N->getOperand(0));
2286   SDValue Hi = DAG.getNode(ISD::EXTRACT_VECTOR_ELT, SL, MVT::i32,
2287                            VecOp, One);
2288 
2289   SDValue NewConst = DAG.getConstant(ShiftAmt - 32, SL, MVT::i32);
2290   SDValue NewShift = DAG.getNode(ISD::SRL, SL, MVT::i32, Hi, NewConst);
2291 
2292   SDValue BuildPair = DAG.getBuildVector(MVT::v2i32, SL, {NewShift, Zero});
2293 
2294   return DAG.getNode(ISD::BITCAST, SL, MVT::i64, BuildPair);
2295 }
2296 
2297 SDValue AMDGPUTargetLowering::performMulCombine(SDNode *N,
2298                                                 DAGCombinerInfo &DCI) const {
2299   EVT VT = N->getValueType(0);
2300 
2301   if (VT.isVector() || VT.getSizeInBits() > 32)
2302     return SDValue();
2303 
2304   SelectionDAG &DAG = DCI.DAG;
2305   SDLoc DL(N);
2306 
2307   SDValue N0 = N->getOperand(0);
2308   SDValue N1 = N->getOperand(1);
2309   SDValue Mul;
2310 
2311   if (Subtarget->hasMulU24() && isU24(N0, DAG) && isU24(N1, DAG)) {
2312     N0 = DAG.getZExtOrTrunc(N0, DL, MVT::i32);
2313     N1 = DAG.getZExtOrTrunc(N1, DL, MVT::i32);
2314     Mul = DAG.getNode(AMDGPUISD::MUL_U24, DL, MVT::i32, N0, N1);
2315   } else if (Subtarget->hasMulI24() && isI24(N0, DAG) && isI24(N1, DAG)) {
2316     N0 = DAG.getSExtOrTrunc(N0, DL, MVT::i32);
2317     N1 = DAG.getSExtOrTrunc(N1, DL, MVT::i32);
2318     Mul = DAG.getNode(AMDGPUISD::MUL_I24, DL, MVT::i32, N0, N1);
2319   } else {
2320     return SDValue();
2321   }
2322 
2323   // We need to use sext even for MUL_U24, because MUL_U24 is used
2324   // for signed multiply of 8 and 16-bit types.
2325   return DAG.getSExtOrTrunc(Mul, DL, VT);
2326 }
2327 
2328 static bool isNegativeOne(SDValue Val) {
2329   if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Val))
2330     return C->isAllOnesValue();
2331   return false;
2332 }
2333 
2334 static bool isCtlzOpc(unsigned Opc) {
2335   return Opc == ISD::CTLZ || Opc == ISD::CTLZ_ZERO_UNDEF;
2336 }
2337 
2338 // Get FFBH node if the incoming op may have been type legalized from a smaller
2339 // type VT.
2340 // Need to match pre-legalized type because the generic legalization inserts the
2341 // add/sub between the select and compare.
2342 static SDValue getFFBH_U32(const TargetLowering &TLI,
2343                            SelectionDAG &DAG, SDLoc SL, SDValue Op) {
2344   EVT VT = Op.getValueType();
2345   EVT LegalVT = TLI.getTypeToTransformTo(*DAG.getContext(), VT);
2346   if (LegalVT != MVT::i32)
2347     return SDValue();
2348 
2349   if (VT != MVT::i32)
2350     Op = DAG.getNode(ISD::ZERO_EXTEND, SL, MVT::i32, Op);
2351 
2352   SDValue FFBH = DAG.getNode(AMDGPUISD::FFBH_U32, SL, MVT::i32, Op);
2353   if (VT != MVT::i32)
2354     FFBH = DAG.getNode(ISD::TRUNCATE, SL, VT, FFBH);
2355 
2356   return FFBH;
2357 }
2358 
2359 // The native instructions return -1 on 0 input. Optimize out a select that
2360 // produces -1 on 0.
2361 //
2362 // TODO: If zero is not undef, we could also do this if the output is compared
2363 // against the bitwidth.
2364 //
2365 // TODO: Should probably combine against FFBH_U32 instead of ctlz directly.
2366 SDValue AMDGPUTargetLowering::performCtlzCombine(SDLoc SL,
2367                                                  SDValue Cond,
2368                                                  SDValue LHS,
2369                                                  SDValue RHS,
2370                                                  DAGCombinerInfo &DCI) const {
2371   ConstantSDNode *CmpRhs = dyn_cast<ConstantSDNode>(Cond.getOperand(1));
2372   if (!CmpRhs || !CmpRhs->isNullValue())
2373     return SDValue();
2374 
2375   SelectionDAG &DAG = DCI.DAG;
2376   ISD::CondCode CCOpcode = cast<CondCodeSDNode>(Cond.getOperand(2))->get();
2377   SDValue CmpLHS = Cond.getOperand(0);
2378 
2379   // select (setcc x, 0, eq), -1, (ctlz_zero_undef x) -> ffbh_u32 x
2380   if (CCOpcode == ISD::SETEQ &&
2381       isCtlzOpc(RHS.getOpcode()) &&
2382       RHS.getOperand(0) == CmpLHS &&
2383       isNegativeOne(LHS)) {
2384     return getFFBH_U32(*this, DAG, SL, CmpLHS);
2385   }
2386 
2387   // select (setcc x, 0, ne), (ctlz_zero_undef x), -1 -> ffbh_u32 x
2388   if (CCOpcode == ISD::SETNE &&
2389       isCtlzOpc(LHS.getOpcode()) &&
2390       LHS.getOperand(0) == CmpLHS &&
2391       isNegativeOne(RHS)) {
2392     return getFFBH_U32(*this, DAG, SL, CmpLHS);
2393   }
2394 
2395   return SDValue();
2396 }
2397 
2398 SDValue AMDGPUTargetLowering::performSelectCombine(SDNode *N,
2399                                                    DAGCombinerInfo &DCI) const {
2400   SDValue Cond = N->getOperand(0);
2401   if (Cond.getOpcode() != ISD::SETCC)
2402     return SDValue();
2403 
2404   EVT VT = N->getValueType(0);
2405   SDValue LHS = Cond.getOperand(0);
2406   SDValue RHS = Cond.getOperand(1);
2407   SDValue CC = Cond.getOperand(2);
2408 
2409   SDValue True = N->getOperand(1);
2410   SDValue False = N->getOperand(2);
2411 
2412   if (VT == MVT::f32 && Cond.hasOneUse()) {
2413     SDValue MinMax
2414       = CombineFMinMaxLegacy(SDLoc(N), VT, LHS, RHS, True, False, CC, DCI);
2415     // Revisit this node so we can catch min3/max3/med3 patterns.
2416     //DCI.AddToWorklist(MinMax.getNode());
2417     return MinMax;
2418   }
2419 
2420   // There's no reason to not do this if the condition has other uses.
2421   return performCtlzCombine(SDLoc(N), Cond, True, False, DCI);
2422 }
2423 
2424 SDValue AMDGPUTargetLowering::PerformDAGCombine(SDNode *N,
2425                                                 DAGCombinerInfo &DCI) const {
2426   SelectionDAG &DAG = DCI.DAG;
2427   SDLoc DL(N);
2428 
2429   switch(N->getOpcode()) {
2430   default:
2431     break;
2432   case ISD::BITCAST: {
2433     EVT DestVT = N->getValueType(0);
2434     if (DestVT.getSizeInBits() != 64 && !DestVT.isVector())
2435       break;
2436 
2437     // Fold bitcasts of constants.
2438     //
2439     // v2i32 (bitcast i64:k) -> build_vector lo_32(k), hi_32(k)
2440     // TODO: Generalize and move to DAGCombiner
2441     SDValue Src = N->getOperand(0);
2442     if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Src)) {
2443       assert(Src.getValueType() == MVT::i64);
2444       SDLoc SL(N);
2445       uint64_t CVal = C->getZExtValue();
2446       return DAG.getNode(ISD::BUILD_VECTOR, SL, DestVT,
2447                          DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
2448                          DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
2449     }
2450 
2451     if (ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Src)) {
2452       const APInt &Val = C->getValueAPF().bitcastToAPInt();
2453       SDLoc SL(N);
2454       uint64_t CVal = Val.getZExtValue();
2455       SDValue Vec = DAG.getNode(ISD::BUILD_VECTOR, SL, MVT::v2i32,
2456                                 DAG.getConstant(Lo_32(CVal), SL, MVT::i32),
2457                                 DAG.getConstant(Hi_32(CVal), SL, MVT::i32));
2458 
2459       return DAG.getNode(ISD::BITCAST, SL, DestVT, Vec);
2460     }
2461 
2462     break;
2463   }
2464   case ISD::SHL: {
2465     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
2466       break;
2467 
2468     return performShlCombine(N, DCI);
2469   }
2470   case ISD::SRL: {
2471     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
2472       break;
2473 
2474     return performSrlCombine(N, DCI);
2475   }
2476   case ISD::SRA: {
2477     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
2478       break;
2479 
2480     return performSraCombine(N, DCI);
2481   }
2482   case ISD::AND: {
2483     if (DCI.getDAGCombineLevel() < AfterLegalizeDAG)
2484       break;
2485 
2486     return performAndCombine(N, DCI);
2487   }
2488   case ISD::MUL:
2489     return performMulCombine(N, DCI);
2490   case AMDGPUISD::MUL_I24:
2491   case AMDGPUISD::MUL_U24: {
2492     SDValue N0 = N->getOperand(0);
2493     SDValue N1 = N->getOperand(1);
2494     simplifyI24(N0, DCI);
2495     simplifyI24(N1, DCI);
2496     return SDValue();
2497   }
2498   case ISD::SELECT:
2499     return performSelectCombine(N, DCI);
2500   case AMDGPUISD::BFE_I32:
2501   case AMDGPUISD::BFE_U32: {
2502     assert(!N->getValueType(0).isVector() &&
2503            "Vector handling of BFE not implemented");
2504     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(N->getOperand(2));
2505     if (!Width)
2506       break;
2507 
2508     uint32_t WidthVal = Width->getZExtValue() & 0x1f;
2509     if (WidthVal == 0)
2510       return DAG.getConstant(0, DL, MVT::i32);
2511 
2512     ConstantSDNode *Offset = dyn_cast<ConstantSDNode>(N->getOperand(1));
2513     if (!Offset)
2514       break;
2515 
2516     SDValue BitsFrom = N->getOperand(0);
2517     uint32_t OffsetVal = Offset->getZExtValue() & 0x1f;
2518 
2519     bool Signed = N->getOpcode() == AMDGPUISD::BFE_I32;
2520 
2521     if (OffsetVal == 0) {
2522       // This is already sign / zero extended, so try to fold away extra BFEs.
2523       unsigned SignBits =  Signed ? (32 - WidthVal + 1) : (32 - WidthVal);
2524 
2525       unsigned OpSignBits = DAG.ComputeNumSignBits(BitsFrom);
2526       if (OpSignBits >= SignBits)
2527         return BitsFrom;
2528 
2529       EVT SmallVT = EVT::getIntegerVT(*DAG.getContext(), WidthVal);
2530       if (Signed) {
2531         // This is a sign_extend_inreg. Replace it to take advantage of existing
2532         // DAG Combines. If not eliminated, we will match back to BFE during
2533         // selection.
2534 
2535         // TODO: The sext_inreg of extended types ends, although we can could
2536         // handle them in a single BFE.
2537         return DAG.getNode(ISD::SIGN_EXTEND_INREG, DL, MVT::i32, BitsFrom,
2538                            DAG.getValueType(SmallVT));
2539       }
2540 
2541       return DAG.getZeroExtendInReg(BitsFrom, DL, SmallVT);
2542     }
2543 
2544     if (ConstantSDNode *CVal = dyn_cast<ConstantSDNode>(BitsFrom)) {
2545       if (Signed) {
2546         return constantFoldBFE<int32_t>(DAG,
2547                                         CVal->getSExtValue(),
2548                                         OffsetVal,
2549                                         WidthVal,
2550                                         DL);
2551       }
2552 
2553       return constantFoldBFE<uint32_t>(DAG,
2554                                        CVal->getZExtValue(),
2555                                        OffsetVal,
2556                                        WidthVal,
2557                                        DL);
2558     }
2559 
2560     if ((OffsetVal + WidthVal) >= 32) {
2561       SDValue ShiftVal = DAG.getConstant(OffsetVal, DL, MVT::i32);
2562       return DAG.getNode(Signed ? ISD::SRA : ISD::SRL, DL, MVT::i32,
2563                          BitsFrom, ShiftVal);
2564     }
2565 
2566     if (BitsFrom.hasOneUse()) {
2567       APInt Demanded = APInt::getBitsSet(32,
2568                                          OffsetVal,
2569                                          OffsetVal + WidthVal);
2570 
2571       APInt KnownZero, KnownOne;
2572       TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
2573                                             !DCI.isBeforeLegalizeOps());
2574       const TargetLowering &TLI = DAG.getTargetLoweringInfo();
2575       if (TLO.ShrinkDemandedConstant(BitsFrom, Demanded) ||
2576           TLI.SimplifyDemandedBits(BitsFrom, Demanded,
2577                                    KnownZero, KnownOne, TLO)) {
2578         DCI.CommitTargetLoweringOpt(TLO);
2579       }
2580     }
2581 
2582     break;
2583   }
2584 
2585   case ISD::STORE:
2586     return performStoreCombine(N, DCI);
2587   }
2588   return SDValue();
2589 }
2590 
2591 //===----------------------------------------------------------------------===//
2592 // Helper functions
2593 //===----------------------------------------------------------------------===//
2594 
2595 void AMDGPUTargetLowering::getOriginalFunctionArgs(
2596                                SelectionDAG &DAG,
2597                                const Function *F,
2598                                const SmallVectorImpl<ISD::InputArg> &Ins,
2599                                SmallVectorImpl<ISD::InputArg> &OrigIns) const {
2600 
2601   for (unsigned i = 0, e = Ins.size(); i < e; ++i) {
2602     if (Ins[i].ArgVT == Ins[i].VT) {
2603       OrigIns.push_back(Ins[i]);
2604       continue;
2605     }
2606 
2607     EVT VT;
2608     if (Ins[i].ArgVT.isVector() && !Ins[i].VT.isVector()) {
2609       // Vector has been split into scalars.
2610       VT = Ins[i].ArgVT.getVectorElementType();
2611     } else if (Ins[i].VT.isVector() && Ins[i].ArgVT.isVector() &&
2612                Ins[i].ArgVT.getVectorElementType() !=
2613                Ins[i].VT.getVectorElementType()) {
2614       // Vector elements have been promoted
2615       VT = Ins[i].ArgVT;
2616     } else {
2617       // Vector has been spilt into smaller vectors.
2618       VT = Ins[i].VT;
2619     }
2620 
2621     ISD::InputArg Arg(Ins[i].Flags, VT, VT, Ins[i].Used,
2622                       Ins[i].OrigArgIndex, Ins[i].PartOffset);
2623     OrigIns.push_back(Arg);
2624   }
2625 }
2626 
2627 SDValue AMDGPUTargetLowering::CreateLiveInRegister(SelectionDAG &DAG,
2628                                                   const TargetRegisterClass *RC,
2629                                                    unsigned Reg, EVT VT) const {
2630   MachineFunction &MF = DAG.getMachineFunction();
2631   MachineRegisterInfo &MRI = MF.getRegInfo();
2632   unsigned VirtualRegister;
2633   if (!MRI.isLiveIn(Reg)) {
2634     VirtualRegister = MRI.createVirtualRegister(RC);
2635     MRI.addLiveIn(Reg, VirtualRegister);
2636   } else {
2637     VirtualRegister = MRI.getLiveInVirtReg(Reg);
2638   }
2639   return DAG.getRegister(VirtualRegister, VT);
2640 }
2641 
2642 uint32_t AMDGPUTargetLowering::getImplicitParameterOffset(
2643     const AMDGPUMachineFunction *MFI, const ImplicitParameter Param) const {
2644   uint64_t ArgOffset = MFI->ABIArgOffset;
2645   switch (Param) {
2646   case GRID_DIM:
2647     return ArgOffset;
2648   case GRID_OFFSET:
2649     return ArgOffset + 4;
2650   }
2651   llvm_unreachable("unexpected implicit parameter type");
2652 }
2653 
2654 #define NODE_NAME_CASE(node) case AMDGPUISD::node: return #node;
2655 
2656 const char* AMDGPUTargetLowering::getTargetNodeName(unsigned Opcode) const {
2657   switch ((AMDGPUISD::NodeType)Opcode) {
2658   case AMDGPUISD::FIRST_NUMBER: break;
2659   // AMDIL DAG nodes
2660   NODE_NAME_CASE(CALL);
2661   NODE_NAME_CASE(UMUL);
2662   NODE_NAME_CASE(RET_FLAG);
2663   NODE_NAME_CASE(BRANCH_COND);
2664 
2665   // AMDGPU DAG nodes
2666   NODE_NAME_CASE(DWORDADDR)
2667   NODE_NAME_CASE(FRACT)
2668   NODE_NAME_CASE(CLAMP)
2669   NODE_NAME_CASE(COS_HW)
2670   NODE_NAME_CASE(SIN_HW)
2671   NODE_NAME_CASE(FMAX_LEGACY)
2672   NODE_NAME_CASE(FMIN_LEGACY)
2673   NODE_NAME_CASE(FMAX3)
2674   NODE_NAME_CASE(SMAX3)
2675   NODE_NAME_CASE(UMAX3)
2676   NODE_NAME_CASE(FMIN3)
2677   NODE_NAME_CASE(SMIN3)
2678   NODE_NAME_CASE(UMIN3)
2679   NODE_NAME_CASE(FMED3)
2680   NODE_NAME_CASE(SMED3)
2681   NODE_NAME_CASE(UMED3)
2682   NODE_NAME_CASE(URECIP)
2683   NODE_NAME_CASE(DIV_SCALE)
2684   NODE_NAME_CASE(DIV_FMAS)
2685   NODE_NAME_CASE(DIV_FIXUP)
2686   NODE_NAME_CASE(TRIG_PREOP)
2687   NODE_NAME_CASE(RCP)
2688   NODE_NAME_CASE(RSQ)
2689   NODE_NAME_CASE(RSQ_LEGACY)
2690   NODE_NAME_CASE(RSQ_CLAMP)
2691   NODE_NAME_CASE(LDEXP)
2692   NODE_NAME_CASE(FP_CLASS)
2693   NODE_NAME_CASE(DOT4)
2694   NODE_NAME_CASE(CARRY)
2695   NODE_NAME_CASE(BORROW)
2696   NODE_NAME_CASE(BFE_U32)
2697   NODE_NAME_CASE(BFE_I32)
2698   NODE_NAME_CASE(BFI)
2699   NODE_NAME_CASE(BFM)
2700   NODE_NAME_CASE(FFBH_U32)
2701   NODE_NAME_CASE(MUL_U24)
2702   NODE_NAME_CASE(MUL_I24)
2703   NODE_NAME_CASE(MAD_U24)
2704   NODE_NAME_CASE(MAD_I24)
2705   NODE_NAME_CASE(TEXTURE_FETCH)
2706   NODE_NAME_CASE(EXPORT)
2707   NODE_NAME_CASE(CONST_ADDRESS)
2708   NODE_NAME_CASE(REGISTER_LOAD)
2709   NODE_NAME_CASE(REGISTER_STORE)
2710   NODE_NAME_CASE(LOAD_INPUT)
2711   NODE_NAME_CASE(SAMPLE)
2712   NODE_NAME_CASE(SAMPLEB)
2713   NODE_NAME_CASE(SAMPLED)
2714   NODE_NAME_CASE(SAMPLEL)
2715   NODE_NAME_CASE(CVT_F32_UBYTE0)
2716   NODE_NAME_CASE(CVT_F32_UBYTE1)
2717   NODE_NAME_CASE(CVT_F32_UBYTE2)
2718   NODE_NAME_CASE(CVT_F32_UBYTE3)
2719   NODE_NAME_CASE(BUILD_VERTICAL_VECTOR)
2720   NODE_NAME_CASE(CONST_DATA_PTR)
2721   case AMDGPUISD::FIRST_MEM_OPCODE_NUMBER: break;
2722   NODE_NAME_CASE(SENDMSG)
2723   NODE_NAME_CASE(INTERP_MOV)
2724   NODE_NAME_CASE(INTERP_P1)
2725   NODE_NAME_CASE(INTERP_P2)
2726   NODE_NAME_CASE(STORE_MSKOR)
2727   NODE_NAME_CASE(LOAD_CONSTANT)
2728   NODE_NAME_CASE(TBUFFER_STORE_FORMAT)
2729   NODE_NAME_CASE(ATOMIC_CMP_SWAP)
2730   NODE_NAME_CASE(ATOMIC_INC)
2731   NODE_NAME_CASE(ATOMIC_DEC)
2732   case AMDGPUISD::LAST_AMDGPU_ISD_NUMBER: break;
2733   }
2734   return nullptr;
2735 }
2736 
2737 SDValue AMDGPUTargetLowering::getRsqrtEstimate(SDValue Operand,
2738                                                DAGCombinerInfo &DCI,
2739                                                unsigned &RefinementSteps,
2740                                                bool &UseOneConstNR) const {
2741   SelectionDAG &DAG = DCI.DAG;
2742   EVT VT = Operand.getValueType();
2743 
2744   if (VT == MVT::f32) {
2745     RefinementSteps = 0;
2746     return DAG.getNode(AMDGPUISD::RSQ, SDLoc(Operand), VT, Operand);
2747   }
2748 
2749   // TODO: There is also f64 rsq instruction, but the documentation is less
2750   // clear on its precision.
2751 
2752   return SDValue();
2753 }
2754 
2755 SDValue AMDGPUTargetLowering::getRecipEstimate(SDValue Operand,
2756                                                DAGCombinerInfo &DCI,
2757                                                unsigned &RefinementSteps) const {
2758   SelectionDAG &DAG = DCI.DAG;
2759   EVT VT = Operand.getValueType();
2760 
2761   if (VT == MVT::f32) {
2762     // Reciprocal, < 1 ulp error.
2763     //
2764     // This reciprocal approximation converges to < 0.5 ulp error with one
2765     // newton rhapson performed with two fused multiple adds (FMAs).
2766 
2767     RefinementSteps = 0;
2768     return DAG.getNode(AMDGPUISD::RCP, SDLoc(Operand), VT, Operand);
2769   }
2770 
2771   // TODO: There is also f64 rcp instruction, but the documentation is less
2772   // clear on its precision.
2773 
2774   return SDValue();
2775 }
2776 
2777 void AMDGPUTargetLowering::computeKnownBitsForTargetNode(
2778   const SDValue Op,
2779   APInt &KnownZero,
2780   APInt &KnownOne,
2781   const SelectionDAG &DAG,
2782   unsigned Depth) const {
2783 
2784   KnownZero = KnownOne = APInt(KnownOne.getBitWidth(), 0); // Don't know anything.
2785 
2786   APInt KnownZero2;
2787   APInt KnownOne2;
2788   unsigned Opc = Op.getOpcode();
2789 
2790   switch (Opc) {
2791   default:
2792     break;
2793   case AMDGPUISD::CARRY:
2794   case AMDGPUISD::BORROW: {
2795     KnownZero = APInt::getHighBitsSet(32, 31);
2796     break;
2797   }
2798 
2799   case AMDGPUISD::BFE_I32:
2800   case AMDGPUISD::BFE_U32: {
2801     ConstantSDNode *CWidth = dyn_cast<ConstantSDNode>(Op.getOperand(2));
2802     if (!CWidth)
2803       return;
2804 
2805     unsigned BitWidth = 32;
2806     uint32_t Width = CWidth->getZExtValue() & 0x1f;
2807 
2808     if (Opc == AMDGPUISD::BFE_U32)
2809       KnownZero = APInt::getHighBitsSet(BitWidth, BitWidth - Width);
2810 
2811     break;
2812   }
2813   }
2814 }
2815 
2816 unsigned AMDGPUTargetLowering::ComputeNumSignBitsForTargetNode(
2817   SDValue Op,
2818   const SelectionDAG &DAG,
2819   unsigned Depth) const {
2820   switch (Op.getOpcode()) {
2821   case AMDGPUISD::BFE_I32: {
2822     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
2823     if (!Width)
2824       return 1;
2825 
2826     unsigned SignBits = 32 - Width->getZExtValue() + 1;
2827     if (!isNullConstant(Op.getOperand(1)))
2828       return SignBits;
2829 
2830     // TODO: Could probably figure something out with non-0 offsets.
2831     unsigned Op0SignBits = DAG.ComputeNumSignBits(Op.getOperand(0), Depth + 1);
2832     return std::max(SignBits, Op0SignBits);
2833   }
2834 
2835   case AMDGPUISD::BFE_U32: {
2836     ConstantSDNode *Width = dyn_cast<ConstantSDNode>(Op.getOperand(2));
2837     return Width ? 32 - (Width->getZExtValue() & 0x1f) : 1;
2838   }
2839 
2840   case AMDGPUISD::CARRY:
2841   case AMDGPUISD::BORROW:
2842     return 31;
2843 
2844   default:
2845     return 1;
2846   }
2847 }
2848