diff --git a/llvm/lib/Target/AMDGPU/AMDGPURewriteAGPRCopyMFMA.cpp b/llvm/lib/Target/AMDGPU/AMDGPURewriteAGPRCopyMFMA.cpp index 0b6c32c45a9b8..bab83483f3de1 100644 --- a/llvm/lib/Target/AMDGPU/AMDGPURewriteAGPRCopyMFMA.cpp +++ b/llvm/lib/Target/AMDGPU/AMDGPURewriteAGPRCopyMFMA.cpp @@ -57,27 +57,47 @@ class AMDGPURewriteAGPRCopyMFMAImpl { TRI(*ST.getRegisterInfo()), MRI(MF.getRegInfo()), VRM(VRM), LRM(LRM), LIS(LIS) {} + // TODO: Remove this restriction + bool mfmaHasSameSrc2AndDstReg(const MachineInstr &MI) const { + const MachineOperand *Src2 = TII.getNamedOperand(MI, AMDGPU::OpName::src2); + const MachineOperand *Dst = TII.getNamedOperand(MI, AMDGPU::OpName::vdst); + return Src2->getReg() == Dst->getReg() && + Src2->getSubReg() == Dst->getSubReg(); + } + + bool isRewriteCandidate(const MachineInstr &MI) const { + return TII.isMAI(MI) && + AMDGPU::getMFMASrcCVDstAGPROp(MI.getOpcode()) != -1 && + mfmaHasSameSrc2AndDstReg(MI); + } + /// Compute the register class constraints based on the uses of \p Reg, - /// excluding uses from \p ExceptMI. This should be nearly identical to + /// excluding MFMA uses from which can be rewritten to change the register + /// class constraint. This should be nearly identical to /// MachineRegisterInfo::recomputeRegClass. const TargetRegisterClass * - recomputeRegClassExcept(Register Reg, const TargetRegisterClass *OldRC, - const TargetRegisterClass *NewRC, - const MachineInstr *ExceptMI) const; + recomputeRegClassExceptRewritable(Register Reg, + const TargetRegisterClass *OldRC, + const TargetRegisterClass *NewRC) const; bool run(MachineFunction &MF) const; }; const TargetRegisterClass * -AMDGPURewriteAGPRCopyMFMAImpl::recomputeRegClassExcept( +AMDGPURewriteAGPRCopyMFMAImpl::recomputeRegClassExceptRewritable( Register Reg, const TargetRegisterClass *OldRC, - const TargetRegisterClass *NewRC, const MachineInstr *ExceptMI) const { + const TargetRegisterClass *NewRC) const { // Accumulate constraints from all uses. for (MachineOperand &MO : MRI.reg_nodbg_operands(Reg)) { // Apply the effect of the given operand to NewRC. MachineInstr *MI = MO.getParent(); - if (MI == ExceptMI) + + // We can swap the classes of dst + src2 as a pair to AGPR, so ignore the + // effects of rewrite candidates. It just so happens that we can use either + // AGPR or VGPR in src0/src1, so don't bother checking the constraint + // effects of the individual operands. + if (isRewriteCandidate(*MI)) continue; unsigned OpNo = &MO - &MI->getOperand(0); @@ -190,10 +210,13 @@ bool AMDGPURewriteAGPRCopyMFMAImpl::run(MachineFunction &MF) const { // first place, as well as need to assign another register, and need to // figure out where to put them. The live range splitting is smarter than // anything we're doing here, so trust it did something reasonable. - const TargetRegisterClass *Src2ExceptRC = recomputeRegClassExcept( - Src2->getReg(), Src2VirtRegRC, VirtRegRC, CopySrcMI); - if (!Src2ExceptRC) + const TargetRegisterClass *Src2ExceptRC = + recomputeRegClassExceptRewritable(Src2->getReg(), Src2VirtRegRC, + VirtRegRC); + if (!Src2ExceptRC) { + LLVM_DEBUG(dbgs() << "Could not recompute the regclass\n"); continue; + } const TargetRegisterClass *NewSrc2ConstraintRC = TII.getRegClass(TII.get(AGPROp), Src2->getOperandNo(), &TRI, MF); @@ -203,8 +226,6 @@ bool AMDGPURewriteAGPRCopyMFMAImpl::run(MachineFunction &MF) const { const TargetRegisterClass *NewSrc2RC = TRI.getCommonSubClass(Src2ExceptRC, NewSrc2ConstraintRC); if (!NewSrc2RC) { - // TODO: This is ignoring ther rewritable uses. e.g. a rewritable MFMA - // using a rewritable MFMA can be rewritten as a pair. LLVM_DEBUG(dbgs() << "Other uses of " << printReg(Src2->getReg(), &TRI) << " are incompatible with replacement class\n"); continue; @@ -215,8 +236,19 @@ bool AMDGPURewriteAGPRCopyMFMAImpl::run(MachineFunction &MF) const { CopySrcMI->setDesc(TII.get(AGPROp)); - // TODO: Is replacing too aggressive, fixup these instructions only? - MRI.replaceRegWith(CopySrcReg, VReg); + // Perform replacement of the register, rewriting the rewritable uses. + for (MachineInstr &UseMI : + make_early_inc_range(MRI.reg_instructions(CopySrcReg))) { + if (TII.isMAI(UseMI)) { + // Note the register we need to rewrite may still appear in src0/src1, + // but that's fine since those can use A or V anyway. + int ReplacementOp = AMDGPU::getMFMASrcCVDstAGPROp(UseMI.getOpcode()); + if (ReplacementOp != -1) + UseMI.setDesc(TII.get(ReplacementOp)); + } + + UseMI.substituteRegister(CopySrcReg, VReg, AMDGPU::NoSubRegister, TRI); + } LLVM_DEBUG(dbgs() << "Replaced VGPR MFMA with AGPR: " << *CopySrcMI); diff --git a/llvm/test/CodeGen/AMDGPU/inflate-reg-class-vgpr-mfma-to-av-with-load-source.mir b/llvm/test/CodeGen/AMDGPU/inflate-reg-class-vgpr-mfma-to-av-with-load-source.mir index b59f2dedd7198..f8848717808cb 100644 --- a/llvm/test/CodeGen/AMDGPU/inflate-reg-class-vgpr-mfma-to-av-with-load-source.mir +++ b/llvm/test/CodeGen/AMDGPU/inflate-reg-class-vgpr-mfma-to-av-with-load-source.mir @@ -296,16 +296,15 @@ body: | ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000) ; CHECK-NEXT: liveins: $vcc, $vgpr0_vgpr1 ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $vgpr2_vgpr3 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, killed $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, killed $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec ; CHECK-NEXT: S_CBRANCH_VCCNZ %bb.1, implicit $vcc ; CHECK-NEXT: S_BRANCH %bb.2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: bb.2: - ; CHECK-NEXT: liveins: $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17:0x00000000FFFFFFFF + ; CHECK-NEXT: liveins: $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15:0x00000000FFFFFFFF ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = COPY killed renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr16_vgpr17_vgpr18_vgpr19_vgpr20_vgpr21_vgpr22_vgpr23 @@ -384,16 +383,15 @@ body: | ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000) ; CHECK-NEXT: liveins: $vcc, $vgpr0_vgpr1 ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $vgpr2_vgpr3 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 killed $vgpr4_vgpr5, $vgpr2_vgpr3, $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 killed $agpr2_agpr3, $agpr0_agpr1, $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec ; CHECK-NEXT: S_CBRANCH_VCCNZ %bb.1, implicit $vcc ; CHECK-NEXT: S_BRANCH %bb.2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: bb.2: - ; CHECK-NEXT: liveins: $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17:0x00000000FFFFFFFF + ; CHECK-NEXT: liveins: $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15:0x00000000FFFFFFFF ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = COPY killed renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr16_vgpr17_vgpr18_vgpr19_vgpr20_vgpr21_vgpr22_vgpr23 @@ -471,16 +469,15 @@ body: | ; CHECK-NEXT: successors: %bb.1(0x40000000), %bb.2(0x40000000) ; CHECK-NEXT: liveins: $vcc, $vgpr0_vgpr1 ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $vgpr2_vgpr3 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec - ; CHECK-NEXT: renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 = V_MFMA_F32_32X32X8F16_mac_vgprcd_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, killed $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1 = GLOBAL_LOAD_DWORDX2 undef renamable $vgpr0_vgpr1, 0, 0, implicit $exec :: (load (s64), addrspace 1) + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec + ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = V_MFMA_F32_32X32X8F16_mac_e64 $vgpr0_vgpr1, $vgpr0_vgpr1, killed $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15, 0, 0, 0, implicit $mode, implicit $exec ; CHECK-NEXT: S_CBRANCH_VCCNZ %bb.1, implicit $vcc ; CHECK-NEXT: S_BRANCH %bb.2 ; CHECK-NEXT: {{ $}} ; CHECK-NEXT: bb.2: - ; CHECK-NEXT: liveins: $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17:0x00000000FFFFFFFF + ; CHECK-NEXT: liveins: $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15:0x00000000FFFFFFFF ; CHECK-NEXT: {{ $}} - ; CHECK-NEXT: renamable $agpr0_agpr1_agpr2_agpr3_agpr4_agpr5_agpr6_agpr7_agpr8_agpr9_agpr10_agpr11_agpr12_agpr13_agpr14_agpr15 = COPY killed renamable $vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7_vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15_vgpr16_vgpr17 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr0_vgpr1_vgpr2_vgpr3_vgpr4_vgpr5_vgpr6_vgpr7 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr8_vgpr9_vgpr10_vgpr11_vgpr12_vgpr13_vgpr14_vgpr15 ; CHECK-NEXT: S_NOP 0, implicit-def $vgpr16_vgpr17_vgpr18_vgpr19_vgpr20_vgpr21_vgpr22_vgpr23