diff --git a/llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp b/llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp index 649eb57b325bf..d39e0805a79c2 100644 --- a/llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp +++ b/llvm/lib/Target/RISCV/RISCVInsertVSETVLI.cpp @@ -999,12 +999,6 @@ bool RISCVInsertVSETVLI::needVSETVLIPHI(const VSETVLIInfo &Require, void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) { VSETVLIInfo CurInfo; - // BBLocalInfo tracks the VL/VTYPE state the same way BBInfo.Change was - // calculated in computeIncomingVLVTYPE. We need this to apply - // canSkipVSETVLIForLoadStore the same way computeIncomingVLVTYPE did. We - // can't include predecessor information in that decision to avoid disagreeing - // with the global analysis. - VSETVLIInfo BBLocalInfo; // Only be set if current VSETVLIInfo is from an explicit VSET(I)VLI. MachineInstr *PrevVSETVLIMI = nullptr; @@ -1020,7 +1014,6 @@ void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) { MI.getOperand(3).setIsDead(false); MI.getOperand(4).setIsDead(false); CurInfo = getInfoForVSETVLI(MI); - BBLocalInfo = getInfoForVSETVLI(MI); PrevVSETVLIMI = &MI; continue; } @@ -1050,22 +1043,12 @@ void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) { // use the predecessor information. assert(BlockInfo[MBB.getNumber()].Pred.isValid() && "Expected a valid predecessor state."); - // Don't use predecessor information if there was an earlier instruction - // in this block that allowed a vsetvli to be skipped for load/store. - if (!(BBLocalInfo.isValid() && - canSkipVSETVLIForLoadStore(MI, NewInfo, BBLocalInfo)) && - needVSETVLI(NewInfo, BlockInfo[MBB.getNumber()].Pred) && + if (needVSETVLI(NewInfo, BlockInfo[MBB.getNumber()].Pred) && needVSETVLIPHI(NewInfo, MBB)) { insertVSETVLI(MBB, MI, NewInfo, BlockInfo[MBB.getNumber()].Pred); CurInfo = NewInfo; - BBLocalInfo = NewInfo; } - - // We must update BBLocalInfo for every vector instruction. - if (!BBLocalInfo.isValid()) - BBLocalInfo = NewInfo; } else { - assert(BBLocalInfo.isValid()); // If this instruction isn't compatible with the previous VL/VTYPE // we need to insert a VSETVLI. // If this is a unit-stride or strided load/store, we may be able to use @@ -1101,7 +1084,6 @@ void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) { if (NeedInsertVSETVLI) insertVSETVLI(MBB, MI, NewInfo, CurInfo); CurInfo = NewInfo; - BBLocalInfo = NewInfo; } } PrevVSETVLIMI = nullptr; @@ -1112,7 +1094,6 @@ void RISCVInsertVSETVLI::emitVSETVLIs(MachineBasicBlock &MBB) { if (MI.isCall() || MI.isInlineAsm() || MI.modifiesRegister(RISCV::VL) || MI.modifiesRegister(RISCV::VTYPE)) { CurInfo = VSETVLIInfo::getUnknown(); - BBLocalInfo = VSETVLIInfo::getUnknown(); PrevVSETVLIMI = nullptr; } } diff --git a/llvm/test/CodeGen/RISCV/rvv/vsetvli-insert-crossbb.mir b/llvm/test/CodeGen/RISCV/rvv/vsetvli-insert-crossbb.mir index 70ac53052e05c..c96c6e5a3f4c4 100644 --- a/llvm/test/CodeGen/RISCV/rvv/vsetvli-insert-crossbb.mir +++ b/llvm/test/CodeGen/RISCV/rvv/vsetvli-insert-crossbb.mir @@ -592,6 +592,10 @@ body: | ; CHECK-NEXT: [[PseudoVADD_VX_M1_:%[0-9]+]]:vr = PseudoVADD_VX_M1 [[PseudoVID_V_M1_]], [[PHI]], -1, 6, implicit $vl, implicit $vtype ; CHECK-NEXT: [[MUL:%[0-9]+]]:gpr = MUL [[PHI]], [[SRLI]] ; CHECK-NEXT: [[ADD:%[0-9]+]]:gpr = ADD [[COPY]], [[MUL]] + ; FIXME: We insert a SEW=32,LMUL=1/2 VSETVLI here but no SEW=64,LMUL=1 + ; VSETVLI before the VADD above. This misconfigures the VADD in the case that + ; the loop takes its backedge. + ; CHECK-NEXT: dead $x0 = PseudoVSETVLIX0 killed $x0, 87, implicit-def $vl, implicit-def $vtype, implicit $vl ; CHECK-NEXT: PseudoVSE32_V_MF2 killed [[PseudoVADD_VX_M1_]], killed [[ADD]], -1, 5, implicit $vl, implicit $vtype ; CHECK-NEXT: [[ADDI:%[0-9]+]]:gpr = ADDI [[PHI]], 1 ; CHECK-NEXT: BLTU [[ADDI]], [[COPY1]], %bb.1 @@ -695,7 +699,7 @@ body: | ; CHECK-NEXT: [[PseudoVMV_S_X_M1_:%[0-9]+]]:vr = PseudoVMV_S_X_M1 [[DEF]], [[COPY5]], 1, 5, implicit $vl, implicit $vtype ; CHECK-NEXT: [[DEF1:%[0-9]+]]:vr = IMPLICIT_DEF ; CHECK-NEXT: [[PseudoVREDSUM_VS_M1_:%[0-9]+]]:vr = PseudoVREDSUM_VS_M1 [[DEF1]], [[PseudoVADD_VV_M1_]], killed [[PseudoVMV_S_X_M1_]], 4, 5, implicit $vl, implicit $vtype - ; FIXME: There should be a VSETVLI here. + ; CHECK-NEXT: dead $x0 = PseudoVSETIVLI 1, 80, implicit-def $vl, implicit-def $vtype ; CHECK-NEXT: PseudoVSE32_V_M1 killed [[PseudoVREDSUM_VS_M1_]], [[COPY]], 1, 5, implicit $vl, implicit $vtype :: (store (s32) into %ir.res) ; CHECK-NEXT: PseudoRET bb.0.entry: