xref: /freebsd/contrib/llvm-project/llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.h (revision 3a56015a2f5d630910177fa79a522bb95511ccf7)
1 //===-- AMDGPUISelDAGToDAG.h - A dag to dag inst selector for AMDGPU ----===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //==-----------------------------------------------------------------------===//
8 //
9 /// \file
10 /// Defines an instruction selector for the AMDGPU target.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_TARGET_AMDGPU_AMDGPUISELDAGTODAG_H
15 #define LLVM_LIB_TARGET_AMDGPU_AMDGPUISELDAGTODAG_H
16 
17 #include "GCNSubtarget.h"
18 #include "SIMachineFunctionInfo.h"
19 #include "SIModeRegisterDefaults.h"
20 #include "llvm/CodeGen/SelectionDAGISel.h"
21 #include "llvm/Target/TargetMachine.h"
22 
23 using namespace llvm;
24 
25 namespace {
26 
27 static inline bool getConstantValue(SDValue N, uint32_t &Out) {
28   // This is only used for packed vectors, where using 0 for undef should
29   // always be good.
30   if (N.isUndef()) {
31     Out = 0;
32     return true;
33   }
34 
35   if (const ConstantSDNode *C = dyn_cast<ConstantSDNode>(N)) {
36     Out = C->getAPIntValue().getSExtValue();
37     return true;
38   }
39 
40   if (const ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(N)) {
41     Out = C->getValueAPF().bitcastToAPInt().getSExtValue();
42     return true;
43   }
44 
45   return false;
46 }
47 
48 // TODO: Handle undef as zero
49 static inline SDNode *packConstantV2I16(const SDNode *N, SelectionDAG &DAG) {
50   assert(N->getOpcode() == ISD::BUILD_VECTOR && N->getNumOperands() == 2);
51   uint32_t LHSVal, RHSVal;
52   if (getConstantValue(N->getOperand(0), LHSVal) &&
53       getConstantValue(N->getOperand(1), RHSVal)) {
54     SDLoc SL(N);
55     uint32_t K = (LHSVal & 0xffff) | (RHSVal << 16);
56     return DAG.getMachineNode(AMDGPU::S_MOV_B32, SL, N->getValueType(0),
57                               DAG.getTargetConstant(K, SL, MVT::i32));
58   }
59 
60   return nullptr;
61 }
62 
63 } // namespace
64 
65 /// AMDGPU specific code to select AMDGPU machine instructions for
66 /// SelectionDAG operations.
67 class AMDGPUDAGToDAGISel : public SelectionDAGISel {
68   // Subtarget - Keep a pointer to the AMDGPU Subtarget around so that we can
69   // make the right decision when generating code for different targets.
70   const GCNSubtarget *Subtarget;
71 
72   // Default FP mode for the current function.
73   SIModeRegisterDefaults Mode;
74 
75   bool EnableLateStructurizeCFG;
76 
77   // Instructions that will be lowered with a final instruction that zeros the
78   // high result bits.
79   bool fp16SrcZerosHighBits(unsigned Opc) const;
80 
81 public:
82   AMDGPUDAGToDAGISel() = delete;
83 
84   explicit AMDGPUDAGToDAGISel(TargetMachine &TM, CodeGenOptLevel OptLevel);
85 
86   bool runOnMachineFunction(MachineFunction &MF) override;
87   bool matchLoadD16FromBuildVector(SDNode *N) const;
88   void PreprocessISelDAG() override;
89   void Select(SDNode *N) override;
90   void PostprocessISelDAG() override;
91 
92 protected:
93   void SelectBuildVector(SDNode *N, unsigned RegClassID);
94 
95 private:
96   std::pair<SDValue, SDValue> foldFrameIndex(SDValue N) const;
97 
98   bool isInlineImmediate(const SDNode *N) const;
99 
100   bool isInlineImmediate(const APInt &Imm) const {
101     return Subtarget->getInstrInfo()->isInlineConstant(Imm);
102   }
103 
104   bool isInlineImmediate(const APFloat &Imm) const {
105     return Subtarget->getInstrInfo()->isInlineConstant(Imm);
106   }
107 
108   bool isVGPRImm(const SDNode *N) const;
109   bool isUniformLoad(const SDNode *N) const;
110   bool isUniformBr(const SDNode *N) const;
111 
112   // Returns true if ISD::AND SDNode `N`'s masking of the shift amount operand's
113   // `ShAmtBits` bits is unneeded.
114   bool isUnneededShiftMask(const SDNode *N, unsigned ShAmtBits) const;
115 
116   bool isBaseWithConstantOffset64(SDValue Addr, SDValue &LHS,
117                                   SDValue &RHS) const;
118 
119   MachineSDNode *buildSMovImm64(SDLoc &DL, uint64_t Val, EVT VT) const;
120 
121   SDNode *glueCopyToOp(SDNode *N, SDValue NewChain, SDValue Glue) const;
122   SDNode *glueCopyToM0(SDNode *N, SDValue Val) const;
123   SDNode *glueCopyToM0LDSInit(SDNode *N) const;
124 
125   const TargetRegisterClass *getOperandRegClass(SDNode *N, unsigned OpNo) const;
126   virtual bool SelectADDRVTX_READ(SDValue Addr, SDValue &Base, SDValue &Offset);
127   virtual bool SelectADDRIndirect(SDValue Addr, SDValue &Base, SDValue &Offset);
128   bool isDSOffsetLegal(SDValue Base, unsigned Offset) const;
129   bool isDSOffset2Legal(SDValue Base, unsigned Offset0, unsigned Offset1,
130                         unsigned Size) const;
131 
132   bool isFlatScratchBaseLegal(SDValue Addr) const;
133   bool isFlatScratchBaseLegalSV(SDValue Addr) const;
134   bool isFlatScratchBaseLegalSVImm(SDValue Addr) const;
135   bool isSOffsetLegalWithImmOffset(SDValue *SOffset, bool Imm32Only,
136                                    bool IsBuffer, int64_t ImmOffset = 0) const;
137 
138   bool SelectDS1Addr1Offset(SDValue Ptr, SDValue &Base, SDValue &Offset) const;
139   bool SelectDS64Bit4ByteAligned(SDValue Ptr, SDValue &Base, SDValue &Offset0,
140                                  SDValue &Offset1) const;
141   bool SelectDS128Bit8ByteAligned(SDValue Ptr, SDValue &Base, SDValue &Offset0,
142                                   SDValue &Offset1) const;
143   bool SelectDSReadWrite2(SDValue Ptr, SDValue &Base, SDValue &Offset0,
144                           SDValue &Offset1, unsigned Size) const;
145   bool SelectMUBUF(SDValue Addr, SDValue &SRsrc, SDValue &VAddr,
146                    SDValue &SOffset, SDValue &Offset, SDValue &Offen,
147                    SDValue &Idxen, SDValue &Addr64) const;
148   bool SelectMUBUFAddr64(SDValue Addr, SDValue &SRsrc, SDValue &VAddr,
149                          SDValue &SOffset, SDValue &Offset) const;
150   bool SelectMUBUFScratchOffen(SDNode *Parent, SDValue Addr, SDValue &RSrc,
151                                SDValue &VAddr, SDValue &SOffset,
152                                SDValue &ImmOffset) const;
153   bool SelectMUBUFScratchOffset(SDNode *Parent, SDValue Addr, SDValue &SRsrc,
154                                 SDValue &Soffset, SDValue &Offset) const;
155 
156   bool SelectMUBUFOffset(SDValue Addr, SDValue &SRsrc, SDValue &Soffset,
157                          SDValue &Offset) const;
158   bool SelectBUFSOffset(SDValue Addr, SDValue &SOffset) const;
159 
160   bool SelectFlatOffsetImpl(SDNode *N, SDValue Addr, SDValue &VAddr,
161                             SDValue &Offset, uint64_t FlatVariant) const;
162   bool SelectFlatOffset(SDNode *N, SDValue Addr, SDValue &VAddr,
163                         SDValue &Offset) const;
164   bool SelectGlobalOffset(SDNode *N, SDValue Addr, SDValue &VAddr,
165                           SDValue &Offset) const;
166   bool SelectScratchOffset(SDNode *N, SDValue Addr, SDValue &VAddr,
167                            SDValue &Offset) const;
168   bool SelectGlobalSAddr(SDNode *N, SDValue Addr, SDValue &SAddr,
169                          SDValue &VOffset, SDValue &Offset) const;
170   bool SelectScratchSAddr(SDNode *N, SDValue Addr, SDValue &SAddr,
171                           SDValue &Offset) const;
172   bool checkFlatScratchSVSSwizzleBug(SDValue VAddr, SDValue SAddr,
173                                      uint64_t ImmOffset) const;
174   bool SelectScratchSVAddr(SDNode *N, SDValue Addr, SDValue &VAddr,
175                            SDValue &SAddr, SDValue &Offset) const;
176 
177   bool SelectSMRDOffset(SDValue ByteOffsetNode, SDValue *SOffset,
178                         SDValue *Offset, bool Imm32Only = false,
179                         bool IsBuffer = false, bool HasSOffset = false,
180                         int64_t ImmOffset = 0) const;
181   SDValue Expand32BitAddress(SDValue Addr) const;
182   bool SelectSMRDBaseOffset(SDValue Addr, SDValue &SBase, SDValue *SOffset,
183                             SDValue *Offset, bool Imm32Only = false,
184                             bool IsBuffer = false, bool HasSOffset = false,
185                             int64_t ImmOffset = 0) const;
186   bool SelectSMRD(SDValue Addr, SDValue &SBase, SDValue *SOffset,
187                   SDValue *Offset, bool Imm32Only = false) const;
188   bool SelectSMRDImm(SDValue Addr, SDValue &SBase, SDValue &Offset) const;
189   bool SelectSMRDImm32(SDValue Addr, SDValue &SBase, SDValue &Offset) const;
190   bool SelectSMRDSgpr(SDValue Addr, SDValue &SBase, SDValue &SOffset) const;
191   bool SelectSMRDSgprImm(SDValue Addr, SDValue &SBase, SDValue &SOffset,
192                          SDValue &Offset) const;
193   bool SelectSMRDBufferImm(SDValue N, SDValue &Offset) const;
194   bool SelectSMRDBufferImm32(SDValue N, SDValue &Offset) const;
195   bool SelectSMRDBufferSgprImm(SDValue N, SDValue &SOffset,
196                                SDValue &Offset) const;
197   bool SelectSMRDPrefetchImm(SDValue Addr, SDValue &SBase,
198                              SDValue &Offset) const;
199   bool SelectMOVRELOffset(SDValue Index, SDValue &Base, SDValue &Offset) const;
200 
201   bool SelectVOP3ModsImpl(SDValue In, SDValue &Src, unsigned &SrcMods,
202                           bool IsCanonicalizing = true,
203                           bool AllowAbs = true) const;
204   bool SelectVOP3Mods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
205   bool SelectVOP3ModsNonCanonicalizing(SDValue In, SDValue &Src,
206                                        SDValue &SrcMods) const;
207   bool SelectVOP3BMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
208   bool SelectVOP3NoMods(SDValue In, SDValue &Src) const;
209   bool SelectVOP3Mods0(SDValue In, SDValue &Src, SDValue &SrcMods,
210                        SDValue &Clamp, SDValue &Omod) const;
211   bool SelectVOP3BMods0(SDValue In, SDValue &Src, SDValue &SrcMods,
212                         SDValue &Clamp, SDValue &Omod) const;
213   bool SelectVOP3NoMods0(SDValue In, SDValue &Src, SDValue &SrcMods,
214                          SDValue &Clamp, SDValue &Omod) const;
215 
216   bool SelectVINTERPModsImpl(SDValue In, SDValue &Src, SDValue &SrcMods,
217                              bool OpSel) const;
218   bool SelectVINTERPMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
219   bool SelectVINTERPModsHi(SDValue In, SDValue &Src, SDValue &SrcMods) const;
220 
221   bool SelectVOP3OMods(SDValue In, SDValue &Src, SDValue &Clamp,
222                        SDValue &Omod) const;
223 
224   bool SelectVOP3PMods(SDValue In, SDValue &Src, SDValue &SrcMods,
225                        bool IsDOT = false) const;
226   bool SelectVOP3PModsDOT(SDValue In, SDValue &Src, SDValue &SrcMods) const;
227 
228   bool SelectVOP3PModsNeg(SDValue In, SDValue &Src) const;
229   bool SelectWMMAOpSelVOP3PMods(SDValue In, SDValue &Src) const;
230 
231   bool SelectWMMAModsF32NegAbs(SDValue In, SDValue &Src,
232                                SDValue &SrcMods) const;
233   bool SelectWMMAModsF16Neg(SDValue In, SDValue &Src, SDValue &SrcMods) const;
234   bool SelectWMMAModsF16NegAbs(SDValue In, SDValue &Src,
235                                SDValue &SrcMods) const;
236   bool SelectWMMAVISrc(SDValue In, SDValue &Src) const;
237 
238   bool SelectSWMMACIndex8(SDValue In, SDValue &Src, SDValue &IndexKey) const;
239   bool SelectSWMMACIndex16(SDValue In, SDValue &Src, SDValue &IndexKey) const;
240 
241   bool SelectVOP3OpSel(SDValue In, SDValue &Src, SDValue &SrcMods) const;
242 
243   bool SelectVOP3OpSelMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
244   bool SelectVOP3PMadMixModsImpl(SDValue In, SDValue &Src,
245                                  unsigned &Mods) const;
246   bool SelectVOP3PMadMixModsExt(SDValue In, SDValue &Src,
247                                 SDValue &SrcMods) const;
248   bool SelectVOP3PMadMixMods(SDValue In, SDValue &Src, SDValue &SrcMods) const;
249 
250   SDValue getHi16Elt(SDValue In) const;
251 
252   SDValue getMaterializedScalarImm32(int64_t Val, const SDLoc &DL) const;
253 
254   void SelectADD_SUB_I64(SDNode *N);
255   void SelectAddcSubb(SDNode *N);
256   void SelectUADDO_USUBO(SDNode *N);
257   void SelectDIV_SCALE(SDNode *N);
258   void SelectMAD_64_32(SDNode *N);
259   void SelectMUL_LOHI(SDNode *N);
260   void SelectFMA_W_CHAIN(SDNode *N);
261   void SelectFMUL_W_CHAIN(SDNode *N);
262   SDNode *getBFE32(bool IsSigned, const SDLoc &DL, SDValue Val, uint32_t Offset,
263                    uint32_t Width);
264   void SelectS_BFEFromShifts(SDNode *N);
265   void SelectS_BFE(SDNode *N);
266   bool isCBranchSCC(const SDNode *N) const;
267   void SelectBRCOND(SDNode *N);
268   void SelectFMAD_FMA(SDNode *N);
269   void SelectFP_EXTEND(SDNode *N);
270   void SelectDSAppendConsume(SDNode *N, unsigned IntrID);
271   void SelectDSBvhStackIntrinsic(SDNode *N);
272   void SelectDS_GWS(SDNode *N, unsigned IntrID);
273   void SelectInterpP1F16(SDNode *N);
274   void SelectINTRINSIC_W_CHAIN(SDNode *N);
275   void SelectINTRINSIC_WO_CHAIN(SDNode *N);
276   void SelectINTRINSIC_VOID(SDNode *N);
277   void SelectWAVE_ADDRESS(SDNode *N);
278   void SelectSTACKRESTORE(SDNode *N);
279 
280 protected:
281   // Include the pieces autogenerated from the target description.
282 #include "AMDGPUGenDAGISel.inc"
283 };
284 
285 class AMDGPUISelDAGToDAGPass : public SelectionDAGISelPass {
286 public:
287   AMDGPUISelDAGToDAGPass(TargetMachine &TM);
288 
289   PreservedAnalyses run(MachineFunction &MF,
290                         MachineFunctionAnalysisManager &MFAM);
291 };
292 
293 class AMDGPUDAGToDAGISelLegacy : public SelectionDAGISelLegacy {
294 public:
295   static char ID;
296 
297   AMDGPUDAGToDAGISelLegacy(TargetMachine &TM, CodeGenOptLevel OptLevel);
298 
299   bool runOnMachineFunction(MachineFunction &MF) override;
300   void getAnalysisUsage(AnalysisUsage &AU) const override;
301   StringRef getPassName() const override;
302 };
303 
304 #endif // LLVM_LIB_TARGET_AMDGPU_AMDGPUISELDAGTODAG_H
305