diff --git a/llvm/lib/Target/AMDGPU/GCNDPPCombine.cpp b/llvm/lib/Target/AMDGPU/GCNDPPCombine.cpp --- a/llvm/lib/Target/AMDGPU/GCNDPPCombine.cpp +++ b/llvm/lib/Target/AMDGPU/GCNDPPCombine.cpp @@ -513,15 +513,32 @@ break; } + auto *Src0 = TII->getNamedOperand(OrigMI, AMDGPU::OpName::src0); + auto *Src1 = TII->getNamedOperand(OrigMI, AMDGPU::OpName::src1); + if (Use != Src0 && !(Use == Src1 && OrigMI.isCommutable())) { // [1] + LLVM_DEBUG(dbgs() << " failed: no suitable operands\n"); + break; + } + + assert(Src0 && "Src1 without Src0?"); + if (Src1 && Src1->isIdenticalTo(*Src0)) { + assert(Src1->isReg()); + LLVM_DEBUG( + dbgs() + << " " << OrigMI + << " failed: DPP register is used more than once per instruction\n"); + break; + } + LLVM_DEBUG(dbgs() << " combining: " << OrigMI); - if (Use == TII->getNamedOperand(OrigMI, AMDGPU::OpName::src0)) { + if (Use == Src0) { if (auto *DPPInst = createDPPInst(OrigMI, MovMI, CombOldVGPR, OldOpndValue, CombBCZ)) { DPPMIs.push_back(DPPInst); Rollback = false; } - } else if (OrigMI.isCommutable() && - Use == TII->getNamedOperand(OrigMI, AMDGPU::OpName::src1)) { + } else { + assert(Use == Src1 && OrigMI.isCommutable()); // by check [1] auto *BB = OrigMI.getParent(); auto *NewMI = BB->getParent()->CloneMachineInstr(&OrigMI); BB->insert(OrigMI, NewMI); @@ -535,8 +552,7 @@ } else LLVM_DEBUG(dbgs() << " failed: cannot be commuted\n"); NewMI->eraseFromParent(); - } else - LLVM_DEBUG(dbgs() << " failed: no suitable operands\n"); + } if (Rollback) break; OrigMIs.push_back(&OrigMI); diff --git a/llvm/test/CodeGen/AMDGPU/dpp_combine.mir b/llvm/test/CodeGen/AMDGPU/dpp_combine.mir --- a/llvm/test/CodeGen/AMDGPU/dpp_combine.mir +++ b/llvm/test/CodeGen/AMDGPU/dpp_combine.mir @@ -833,3 +833,33 @@ S_ENDPGM 0, implicit %4 ... + +# GCN-LABEL: name: dont_combine_more_than_one_operand +# GCN: %3:vgpr_32 = V_MAX_F32_e64 0, %2, 0, %2, 0, 0, implicit $mode, implicit $exec +name: dont_combine_more_than_one_operand +tracksRegLiveness: true +body: | + bb.0: + liveins: $vgpr0, $vgpr1 + %0:vgpr_32 = COPY $vgpr0 + %1:vgpr_32 = COPY $vgpr1 + %2:vgpr_32 = V_MOV_B32_dpp %0, %1, 1, 15, 15, 1, implicit $exec + %3:vgpr_32 = V_MAX_F32_e64 0, %2, 0, %2, 0, 0, implicit $mode, implicit $exec +... + +# GCN-LABEL: name: dont_combine_more_than_one_operand_dpp_reg_sequence +# GCN: %5:vgpr_32 = V_ADD_I32_e32 %4.sub0, %4.sub0, implicit-def $vcc, implicit $exec +# GCN: %6:vgpr_32 = V_ADDC_U32_e32 %4.sub1, %4.sub1, implicit-def $vcc, implicit $vcc, implicit $exec +name: dont_combine_more_than_one_operand_dpp_reg_sequence +tracksRegLiveness: true +body: | + bb.0: + liveins: $vgpr0_vgpr1, $vgpr2_vgpr3 + %0:vreg_64 = COPY $vgpr0_vgpr1 + %1:vreg_64 = COPY $vgpr2_vgpr3 + %2:vgpr_32 = V_MOV_B32_dpp %0.sub0, %1.sub0, 1, 15, 15, 1, implicit $exec + %3:vgpr_32 = V_MOV_B32_dpp %0.sub1, %1.sub1, 1, 15, 15, 1, implicit $exec + %4:vreg_64 = REG_SEQUENCE %2, %subreg.sub0, %3, %subreg.sub1 + %5:vgpr_32 = V_ADD_I32_e32 %4.sub0, %4.sub0, implicit-def $vcc, implicit $exec + %6:vgpr_32 = V_ADDC_U32_e32 %4.sub1, %4.sub1, implicit-def $vcc, implicit $vcc, implicit $exec +...