1 //===-- GCNHazardRecognizers.h - GCN Hazard Recognizers ---------*- C++ -*-===// 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 // This file defines hazard recognizers for scheduling on GCN processors. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #ifndef LLVM_LIB_TARGET_AMDGPUHAZARDRECOGNIZERS_H 14 #define LLVM_LIB_TARGET_AMDGPUHAZARDRECOGNIZERS_H 15 16 #include "llvm/ADT/BitVector.h" 17 #include "llvm/ADT/STLExtras.h" 18 #include "llvm/CodeGen/ScheduleHazardRecognizer.h" 19 #include "llvm/CodeGen/TargetSchedule.h" 20 #include <list> 21 22 namespace llvm { 23 24 class MachineFunction; 25 class MachineInstr; 26 class MachineOperand; 27 class MachineRegisterInfo; 28 class SIInstrInfo; 29 class SIRegisterInfo; 30 class GCNSubtarget; 31 32 class GCNHazardRecognizer final : public ScheduleHazardRecognizer { 33 public: 34 typedef function_ref<bool(const MachineInstr &)> IsHazardFn; 35 36 private: 37 // Distinguish if we are called from scheduler or hazard recognizer 38 bool IsHazardRecognizerMode; 39 40 // This variable stores the instruction that has been emitted this cycle. It 41 // will be added to EmittedInstrs, when AdvanceCycle() or RecedeCycle() is 42 // called. 43 MachineInstr *CurrCycleInstr; 44 std::list<MachineInstr*> EmittedInstrs; 45 const MachineFunction &MF; 46 const GCNSubtarget &ST; 47 const SIInstrInfo &TII; 48 const SIRegisterInfo &TRI; 49 TargetSchedModel TSchedModel; 50 bool RunLdsBranchVmemWARHazardFixup; 51 52 /// RegUnits of uses in the current soft memory clause. 53 BitVector ClauseUses; 54 55 /// RegUnits of defs in the current soft memory clause. 56 BitVector ClauseDefs; 57 58 void resetClause() { 59 ClauseUses.reset(); 60 ClauseDefs.reset(); 61 } 62 63 void addClauseInst(const MachineInstr &MI); 64 65 /// \returns the number of wait states before another MFMA instruction can be 66 /// issued after \p MI. 67 unsigned getMFMAPipelineWaitStates(const MachineInstr &MI) const; 68 69 // Advance over a MachineInstr bundle. Look for hazards in the bundled 70 // instructions. 71 void processBundle(); 72 73 // Run on an individual instruction in hazard recognizer mode. This can be 74 // used on a newly inserted instruction before returning from PreEmitNoops. 75 void runOnInstruction(MachineInstr *MI); 76 77 int getWaitStatesSince(IsHazardFn IsHazard, int Limit); 78 int getWaitStatesSinceDef(unsigned Reg, IsHazardFn IsHazardDef, int Limit); 79 int getWaitStatesSinceSetReg(IsHazardFn IsHazard, int Limit); 80 81 int checkSoftClauseHazards(MachineInstr *SMEM); 82 int checkSMRDHazards(MachineInstr *SMRD); 83 int checkVMEMHazards(MachineInstr* VMEM); 84 int checkDPPHazards(MachineInstr *DPP); 85 int checkDivFMasHazards(MachineInstr *DivFMas); 86 int checkGetRegHazards(MachineInstr *GetRegInstr); 87 int checkSetRegHazards(MachineInstr *SetRegInstr); 88 int createsVALUHazard(const MachineInstr &MI); 89 int checkVALUHazards(MachineInstr *VALU); 90 int checkVALUHazardsHelper(const MachineOperand &Def, const MachineRegisterInfo &MRI); 91 int checkRWLaneHazards(MachineInstr *RWLane); 92 int checkRFEHazards(MachineInstr *RFE); 93 int checkInlineAsmHazards(MachineInstr *IA); 94 int checkReadM0Hazards(MachineInstr *SMovRel); 95 int checkNSAtoVMEMHazard(MachineInstr *MI); 96 int checkFPAtomicToDenormModeHazard(MachineInstr *MI); 97 void fixHazards(MachineInstr *MI); 98 bool fixVcmpxPermlaneHazards(MachineInstr *MI); 99 bool fixVMEMtoScalarWriteHazards(MachineInstr *MI); 100 bool fixSMEMtoVectorWriteHazards(MachineInstr *MI); 101 bool fixVcmpxExecWARHazard(MachineInstr *MI); 102 bool fixLdsBranchVmemWARHazard(MachineInstr *MI); 103 bool fixLdsDirectVALUHazard(MachineInstr *MI); 104 bool fixLdsDirectVMEMHazard(MachineInstr *MI); 105 bool fixVALUPartialForwardingHazard(MachineInstr *MI); 106 bool fixVALUTransUseHazard(MachineInstr *MI); 107 bool fixWMMAHazards(MachineInstr *MI); 108 bool fixShift64HighRegBug(MachineInstr *MI); 109 bool fixVALUMaskWriteHazard(MachineInstr *MI); 110 111 int checkMAIHazards(MachineInstr *MI); 112 int checkMAIHazards908(MachineInstr *MI); 113 int checkMAIHazards90A(MachineInstr *MI); 114 /// Pad the latency between neighboring MFMA instructions with s_nops. The 115 /// percentage of wait states to fill with s_nops is specified by the command 116 /// line option '-amdgpu-mfma-padding-ratio'. 117 /// 118 /// For example, with '-amdgpu-mfma-padding-ratio=100': 119 /// 120 /// 2 pass MFMA instructions have a latency of 2 wait states. Therefore, a 121 /// 'S_NOP 1' will be added between sequential MFMA instructions. 122 /// 123 /// V_MFMA_F32_4X4X1F32 124 /// V_MFMA_F32_4X4X1F32 125 ///--> 126 /// V_MFMA_F32_4X4X1F32 127 /// S_NOP 1 128 /// V_MFMA_F32_4X4X1F32 129 int checkMFMAPadding(MachineInstr *MI); 130 int checkMAIVALUHazards(MachineInstr *MI); 131 int checkMAILdStHazards(MachineInstr *MI); 132 133 public: 134 GCNHazardRecognizer(const MachineFunction &MF); 135 // We can only issue one instruction per cycle. 136 bool atIssueLimit() const override { return true; } 137 void EmitInstruction(SUnit *SU) override; 138 void EmitInstruction(MachineInstr *MI) override; 139 HazardType getHazardType(SUnit *SU, int Stalls) override; 140 void EmitNoop() override; 141 unsigned PreEmitNoops(MachineInstr *) override; 142 unsigned PreEmitNoopsCommon(MachineInstr *); 143 void AdvanceCycle() override; 144 void RecedeCycle() override; 145 bool ShouldPreferAnother(SUnit *SU) override; 146 void Reset() override; 147 }; 148 149 } // end namespace llvm 150 151 #endif //LLVM_LIB_TARGET_AMDGPUHAZARDRECOGNIZERS_H 152