diff options
Diffstat (limited to 'llvm/lib/Target/RISCV')
| -rw-r--r-- | llvm/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp | 82 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp | 10 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVFeatures.td | 5 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVISelLowering.cpp | 18 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfo.cpp | 19 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfo.td | 4 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfoD.td | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfoF.td | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfoP.td | 5 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVInstrInfoSFB.td | 4 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp | 1 | ||||
| -rw-r--r-- | llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp | 31 |
13 files changed, 148 insertions, 34 deletions
diff --git a/llvm/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp b/llvm/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp index 8198173..282cf5d 100644 --- a/llvm/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp +++ b/llvm/lib/Target/RISCV/GISel/RISCVInstructionSelector.cpp @@ -92,6 +92,10 @@ private: void emitFence(AtomicOrdering FenceOrdering, SyncScope::ID FenceSSID, MachineIRBuilder &MIB) const; bool selectUnmergeValues(MachineInstr &MI, MachineIRBuilder &MIB) const; + void addVectorLoadStoreOperands(MachineInstr &I, + SmallVectorImpl<SrcOp> &SrcOps, + unsigned &CurOp, bool IsMasked, + bool IsStrided) const; bool selectIntrinsicWithSideEffects(MachineInstr &I, MachineIRBuilder &MIB) const; @@ -716,6 +720,26 @@ static unsigned selectRegImmLoadStoreOp(unsigned GenericOpc, unsigned OpSize) { return GenericOpc; } +void RISCVInstructionSelector::addVectorLoadStoreOperands( + MachineInstr &I, SmallVectorImpl<SrcOp> &SrcOps, unsigned &CurOp, + bool IsMasked, bool IsStrided) const { + // Base Pointer + auto PtrReg = I.getOperand(CurOp++).getReg(); + SrcOps.push_back(PtrReg); + + // Stride + if (IsStrided) { + auto StrideReg = I.getOperand(CurOp++).getReg(); + SrcOps.push_back(StrideReg); + } + + // Mask + if (IsMasked) { + auto MaskReg = I.getOperand(CurOp++).getReg(); + SrcOps.push_back(MaskReg); + } +} + bool RISCVInstructionSelector::selectIntrinsicWithSideEffects( MachineInstr &I, MachineIRBuilder &MIB) const { // Find the intrinsic ID. @@ -752,21 +776,7 @@ bool RISCVInstructionSelector::selectIntrinsicWithSideEffects( SrcOps.push_back(Register(RISCV::NoRegister)); } - // Base Pointer - auto PtrReg = I.getOperand(CurOp++).getReg(); - SrcOps.push_back(PtrReg); - - // Stride - if (IsStrided) { - auto StrideReg = I.getOperand(CurOp++).getReg(); - SrcOps.push_back(StrideReg); - } - - // Mask - if (IsMasked) { - auto MaskReg = I.getOperand(CurOp++).getReg(); - SrcOps.push_back(MaskReg); - } + addVectorLoadStoreOperands(I, SrcOps, CurOp, IsMasked, IsStrided); RISCVVType::VLMUL LMUL = RISCVTargetLowering::getLMUL(getMVTForLLT(VT)); const RISCV::VLEPseudo *P = @@ -795,6 +805,48 @@ bool RISCVInstructionSelector::selectIntrinsicWithSideEffects( I.eraseFromParent(); return constrainSelectedInstRegOperands(*PseudoMI, TII, TRI, RBI); } + case Intrinsic::riscv_vsm: + case Intrinsic::riscv_vse: + case Intrinsic::riscv_vse_mask: + case Intrinsic::riscv_vsse: + case Intrinsic::riscv_vsse_mask: { + bool IsMasked = IntrinID == Intrinsic::riscv_vse_mask || + IntrinID == Intrinsic::riscv_vsse_mask; + bool IsStrided = IntrinID == Intrinsic::riscv_vsse || + IntrinID == Intrinsic::riscv_vsse_mask; + LLT VT = MRI->getType(I.getOperand(1).getReg()); + unsigned Log2SEW = Log2_32(VT.getScalarSizeInBits()); + + // Sources + unsigned CurOp = 1; + SmallVector<SrcOp, 4> SrcOps; // Source registers. + + // Store value + auto PassthruReg = I.getOperand(CurOp++).getReg(); + SrcOps.push_back(PassthruReg); + + addVectorLoadStoreOperands(I, SrcOps, CurOp, IsMasked, IsStrided); + + RISCVVType::VLMUL LMUL = RISCVTargetLowering::getLMUL(getMVTForLLT(VT)); + const RISCV::VSEPseudo *P = RISCV::getVSEPseudo( + IsMasked, IsStrided, Log2SEW, static_cast<unsigned>(LMUL)); + + auto PseudoMI = MIB.buildInstr(P->Pseudo, {}, SrcOps); + + // Select VL + auto VLOpFn = renderVLOp(I.getOperand(CurOp++)); + for (auto &RenderFn : *VLOpFn) + RenderFn(PseudoMI); + + // SEW + PseudoMI.addImm(Log2SEW); + + // Memref + PseudoMI.cloneMemRefs(I); + + I.eraseFromParent(); + return constrainSelectedInstRegOperands(*PseudoMI, TII, TRI, RBI); + } } } diff --git a/llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp b/llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp index 4105618..526675a 100644 --- a/llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp +++ b/llvm/lib/Target/RISCV/RISCVExpandPseudoInsts.cpp @@ -127,6 +127,10 @@ bool RISCVExpandPseudo::expandMI(MachineBasicBlock &MBB, case RISCV::PseudoCCAND: case RISCV::PseudoCCOR: case RISCV::PseudoCCXOR: + case RISCV::PseudoCCMAX: + case RISCV::PseudoCCMAXU: + case RISCV::PseudoCCMIN: + case RISCV::PseudoCCMINU: case RISCV::PseudoCCADDW: case RISCV::PseudoCCSUBW: case RISCV::PseudoCCSLL: @@ -217,6 +221,7 @@ bool RISCVExpandPseudo::expandCCOp(MachineBasicBlock &MBB, .addImm(0); } else { unsigned NewOpc; + // clang-format off switch (MI.getOpcode()) { default: llvm_unreachable("Unexpected opcode!"); @@ -228,6 +233,10 @@ bool RISCVExpandPseudo::expandCCOp(MachineBasicBlock &MBB, case RISCV::PseudoCCAND: NewOpc = RISCV::AND; break; case RISCV::PseudoCCOR: NewOpc = RISCV::OR; break; case RISCV::PseudoCCXOR: NewOpc = RISCV::XOR; break; + case RISCV::PseudoCCMAX: NewOpc = RISCV::MAX; break; + case RISCV::PseudoCCMIN: NewOpc = RISCV::MIN; break; + case RISCV::PseudoCCMAXU: NewOpc = RISCV::MAXU; break; + case RISCV::PseudoCCMINU: NewOpc = RISCV::MINU; break; case RISCV::PseudoCCADDI: NewOpc = RISCV::ADDI; break; case RISCV::PseudoCCSLLI: NewOpc = RISCV::SLLI; break; case RISCV::PseudoCCSRLI: NewOpc = RISCV::SRLI; break; @@ -250,6 +259,7 @@ bool RISCVExpandPseudo::expandCCOp(MachineBasicBlock &MBB, case RISCV::PseudoCCNDS_BFOS: NewOpc = RISCV::NDS_BFOS; break; case RISCV::PseudoCCNDS_BFOZ: NewOpc = RISCV::NDS_BFOZ; break; } + // clang-format on if (NewOpc == RISCV::NDS_BFOZ || NewOpc == RISCV::NDS_BFOS) { BuildMI(TrueBB, DL, TII->get(NewOpc), DestReg) diff --git a/llvm/lib/Target/RISCV/RISCVFeatures.td b/llvm/lib/Target/RISCV/RISCVFeatures.td index b4556f6..cfee6ab 100644 --- a/llvm/lib/Target/RISCV/RISCVFeatures.td +++ b/llvm/lib/Target/RISCV/RISCVFeatures.td @@ -1851,6 +1851,11 @@ def TuneShortForwardBranchOpt def HasShortForwardBranchOpt : Predicate<"Subtarget->hasShortForwardBranchOpt()">; def NoShortForwardBranchOpt : Predicate<"!Subtarget->hasShortForwardBranchOpt()">; +def TuneShortForwardBranchIMinMax + : SubtargetFeature<"short-forward-branch-i-minmax", "HasShortForwardBranchIMinMax", + "true", "Enable short forward branch optimization for min,max instructions in Zbb", + [TuneShortForwardBranchOpt]>; + // Some subtargets require a S2V transfer buffer to move scalars into vectors. // FIXME: Forming .vx/.vf/.wx/.wf can reduce register pressure. def TuneNoSinkSplatOperands diff --git a/llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp b/llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp index 9a6afa1..b25a054 100644 --- a/llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp +++ b/llvm/lib/Target/RISCV/RISCVISelDAGToDAG.cpp @@ -3995,6 +3995,7 @@ bool RISCVDAGToDAGISel::hasAllNBitUsers(SDNode *Node, unsigned Bits, case RISCV::CTZW: case RISCV::CPOPW: case RISCV::SLLI_UW: + case RISCV::ABSW: case RISCV::FMV_W_X: case RISCV::FCVT_H_W: case RISCV::FCVT_H_W_INX: diff --git a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp index 1c930ac..c6a8b84 100644 --- a/llvm/lib/Target/RISCV/RISCVISelLowering.cpp +++ b/llvm/lib/Target/RISCV/RISCVISelLowering.cpp @@ -433,6 +433,8 @@ RISCVTargetLowering::RISCVTargetLowering(const TargetMachine &TM, if (Subtarget.hasStdExtP() || (Subtarget.hasVendorXCValu() && !Subtarget.is64Bit())) { setOperationAction(ISD::ABS, XLenVT, Legal); + if (Subtarget.is64Bit()) + setOperationAction(ISD::ABS, MVT::i32, Custom); } else if (Subtarget.hasShortForwardBranchOpt()) { // We can use PseudoCCSUB to implement ABS. setOperationAction(ISD::ABS, XLenVT, Legal); @@ -14816,8 +14818,16 @@ void RISCVTargetLowering::ReplaceNodeResults(SDNode *N, assert(N->getValueType(0) == MVT::i32 && Subtarget.is64Bit() && "Unexpected custom legalisation"); + if (Subtarget.hasStdExtP()) { + SDValue Src = + DAG.getNode(ISD::ANY_EXTEND, DL, MVT::i64, N->getOperand(0)); + SDValue Abs = DAG.getNode(RISCVISD::ABSW, DL, MVT::i64, Src); + Results.push_back(DAG.getNode(ISD::TRUNCATE, DL, MVT::i32, Abs)); + return; + } + if (Subtarget.hasStdExtZbb()) { - // Emit a special ABSW node that will be expanded to NEGW+MAX at isel. + // Emit a special node that will be expanded to NEGW+MAX at isel. // This allows us to remember that the result is sign extended. Expanding // to NEGW+MAX here requires a Freeze which breaks ComputeNumSignBits. SDValue Src = DAG.getNode(ISD::SIGN_EXTEND, DL, MVT::i64, @@ -19784,7 +19794,9 @@ legalizeScatterGatherIndexType(SDLoc DL, SDValue &Index, // LLVM's legalization take care of the splitting. // FIXME: LLVM can't split VP_GATHER or VP_SCATTER yet. Index = DAG.getNode(ISD::SIGN_EXTEND, DL, - IndexVT.changeVectorElementType(XLenVT), Index); + EVT::getVectorVT(*DAG.getContext(), XLenVT, + IndexVT.getVectorElementCount()), + Index); } IndexType = ISD::UNSIGNED_SCALED; return true; @@ -20290,6 +20302,7 @@ SDValue RISCVTargetLowering::PerformDAGCombine(SDNode *N, break; } + case RISCVISD::ABSW: case RISCVISD::CLZW: case RISCVISD::CTZW: { // Only the lower 32 bits of the first operand are read @@ -21862,6 +21875,7 @@ unsigned RISCVTargetLowering::ComputeNumSignBitsForTargetNode( case RISCVISD::REMUW: case RISCVISD::ROLW: case RISCVISD::RORW: + case RISCVISD::ABSW: case RISCVISD::FCVT_W_RV64: case RISCVISD::FCVT_WU_RV64: case RISCVISD::STRICT_FCVT_W_RV64: diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp index 912b82d..c9df787 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp +++ b/llvm/lib/Target/RISCV/RISCVInstrInfo.cpp @@ -869,7 +869,7 @@ std::optional<unsigned> getFoldedOpcode(MachineFunction &MF, MachineInstr &MI, } } -// This is the version used during inline spilling +// This is the version used during InlineSpiller::spillAroundUses MachineInstr *RISCVInstrInfo::foldMemoryOperandImpl( MachineFunction &MF, MachineInstr &MI, ArrayRef<unsigned> Ops, MachineBasicBlock::iterator InsertPt, int FrameIndex, LiveIntervals *LIS, @@ -1699,6 +1699,10 @@ unsigned getPredicatedOpcode(unsigned Opcode) { case RISCV::AND: return RISCV::PseudoCCAND; case RISCV::OR: return RISCV::PseudoCCOR; case RISCV::XOR: return RISCV::PseudoCCXOR; + case RISCV::MAX: return RISCV::PseudoCCMAX; + case RISCV::MAXU: return RISCV::PseudoCCMAXU; + case RISCV::MIN: return RISCV::PseudoCCMIN; + case RISCV::MINU: return RISCV::PseudoCCMINU; case RISCV::ADDI: return RISCV::PseudoCCADDI; case RISCV::SLLI: return RISCV::PseudoCCSLLI; @@ -1735,7 +1739,8 @@ unsigned getPredicatedOpcode(unsigned Opcode) { /// return the defining instruction. static MachineInstr *canFoldAsPredicatedOp(Register Reg, const MachineRegisterInfo &MRI, - const TargetInstrInfo *TII) { + const TargetInstrInfo *TII, + const RISCVSubtarget &STI) { if (!Reg.isVirtual()) return nullptr; if (!MRI.hasOneNonDBGUse(Reg)) @@ -1743,6 +1748,12 @@ static MachineInstr *canFoldAsPredicatedOp(Register Reg, MachineInstr *MI = MRI.getVRegDef(Reg); if (!MI) return nullptr; + + if (!STI.hasShortForwardBranchIMinMax() && + (MI->getOpcode() == RISCV::MAX || MI->getOpcode() == RISCV::MIN || + MI->getOpcode() == RISCV::MINU || MI->getOpcode() == RISCV::MAXU)) + return nullptr; + // Check if MI can be predicated and folded into the CCMOV. if (getPredicatedOpcode(MI->getOpcode()) == RISCV::INSTRUCTION_LIST_END) return nullptr; @@ -1806,10 +1817,10 @@ RISCVInstrInfo::optimizeSelect(MachineInstr &MI, MachineRegisterInfo &MRI = MI.getParent()->getParent()->getRegInfo(); MachineInstr *DefMI = - canFoldAsPredicatedOp(MI.getOperand(5).getReg(), MRI, this); + canFoldAsPredicatedOp(MI.getOperand(5).getReg(), MRI, this, STI); bool Invert = !DefMI; if (!DefMI) - DefMI = canFoldAsPredicatedOp(MI.getOperand(4).getReg(), MRI, this); + DefMI = canFoldAsPredicatedOp(MI.getOperand(4).getReg(), MRI, this, STI); if (!DefMI) return nullptr; diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfo.td b/llvm/lib/Target/RISCV/RISCVInstrInfo.td index 7c89686..9cb53fb 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfo.td +++ b/llvm/lib/Target/RISCV/RISCVInstrInfo.td @@ -768,7 +768,7 @@ def BGE : BranchCC_rri<0b101, "bge">; def BLTU : BranchCC_rri<0b110, "bltu">; def BGEU : BranchCC_rri<0b111, "bgeu">; -let IsSignExtendingOpW = 1 in { +let IsSignExtendingOpW = 1, canFoldAsLoad = 1 in { def LB : Load_ri<0b000, "lb">, Sched<[WriteLDB, ReadMemBase]>; def LH : Load_ri<0b001, "lh">, Sched<[WriteLDH, ReadMemBase]>; def LW : Load_ri<0b010, "lw">, Sched<[WriteLDW, ReadMemBase]>; @@ -889,8 +889,10 @@ def CSRRCI : CSR_ii<0b111, "csrrci">; /// RV64I instructions let Predicates = [IsRV64] in { +let canFoldAsLoad = 1 in { def LWU : Load_ri<0b110, "lwu">, Sched<[WriteLDW, ReadMemBase]>; def LD : Load_ri<0b011, "ld">, Sched<[WriteLDD, ReadMemBase]>; +} def SD : Store_rri<0b011, "sd">, Sched<[WriteSTD, ReadStoreData, ReadMemBase]>; let IsSignExtendingOpW = 1 in { diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoD.td b/llvm/lib/Target/RISCV/RISCVInstrInfoD.td index afac37d..4ffe3e6 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfoD.td +++ b/llvm/lib/Target/RISCV/RISCVInstrInfoD.td @@ -71,6 +71,7 @@ defvar DExtsRV64 = [DExt, ZdinxExt]; //===----------------------------------------------------------------------===// let Predicates = [HasStdExtD] in { +let canFoldAsLoad = 1 in def FLD : FPLoad_r<0b011, "fld", FPR64, WriteFLD64>; // Operands for stores are in the order srcreg, base, offset rather than diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoF.td b/llvm/lib/Target/RISCV/RISCVInstrInfoF.td index 6571d99..b30f8ec 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfoF.td +++ b/llvm/lib/Target/RISCV/RISCVInstrInfoF.td @@ -330,6 +330,7 @@ class PseudoFROUND<DAGOperand Ty, ValueType vt, ValueType intvt = XLenVT> //===----------------------------------------------------------------------===// let Predicates = [HasStdExtF] in { +let canFoldAsLoad = 1 in def FLW : FPLoad_r<0b010, "flw", FPR32, WriteFLD32>; // Operands for stores are in the order srcreg, base, offset rather than diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoP.td b/llvm/lib/Target/RISCV/RISCVInstrInfoP.td index cc085bb..4cbbba3 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfoP.td +++ b/llvm/lib/Target/RISCV/RISCVInstrInfoP.td @@ -1461,5 +1461,10 @@ let Predicates = [HasStdExtP, IsRV32] in { // Codegen patterns //===----------------------------------------------------------------------===// +def riscv_absw : RVSDNode<"ABSW", SDTIntUnaryOp>; + let Predicates = [HasStdExtP] in def : PatGpr<abs, ABS>; + +let Predicates = [HasStdExtP, IsRV64] in +def : PatGpr<riscv_absw, ABSW>; diff --git a/llvm/lib/Target/RISCV/RISCVInstrInfoSFB.td b/llvm/lib/Target/RISCV/RISCVInstrInfoSFB.td index 0114fbd..5a67a5a 100644 --- a/llvm/lib/Target/RISCV/RISCVInstrInfoSFB.td +++ b/llvm/lib/Target/RISCV/RISCVInstrInfoSFB.td @@ -106,6 +106,10 @@ def PseudoCCSRA : SFBALU_rr; def PseudoCCAND : SFBALU_rr; def PseudoCCOR : SFBALU_rr; def PseudoCCXOR : SFBALU_rr; +def PseudoCCMAX : SFBALU_rr; +def PseudoCCMIN : SFBALU_rr; +def PseudoCCMAXU : SFBALU_rr; +def PseudoCCMINU : SFBALU_rr; def PseudoCCADDI : SFBALU_ri; def PseudoCCANDI : SFBALU_ri; diff --git a/llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp b/llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp index d08115b..ea98cdb 100644 --- a/llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp +++ b/llvm/lib/Target/RISCV/RISCVOptWInstrs.cpp @@ -172,6 +172,7 @@ static bool hasAllNBitUsers(const MachineInstr &OrigMI, case RISCV::CTZW: case RISCV::CPOPW: case RISCV::SLLI_UW: + case RISCV::ABSW: case RISCV::FMV_W_X: case RISCV::FCVT_H_W: case RISCV::FCVT_H_W_INX: diff --git a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp index e9f43b9..84bb294 100644 --- a/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp +++ b/llvm/lib/Target/RISCV/RISCVRegisterInfo.cpp @@ -438,18 +438,19 @@ void RISCVRegisterInfo::lowerSegmentSpillReload(MachineBasicBlock::iterator II, TypeSize VRegSize = OldLoc.getValue().divideCoefficientBy(NumRegs); Register VLENB = 0; - unsigned PreHandledNum = 0; + unsigned VLENBShift = 0; + unsigned PrevHandledNum = 0; unsigned I = 0; while (I != NumRegs) { auto [LMulHandled, RegClass, Opcode] = getSpillReloadInfo(NumRegs - I, RegEncoding, IsSpill); auto [RegNumHandled, _] = RISCVVType::decodeVLMUL(LMulHandled); bool IsLast = I + RegNumHandled == NumRegs; - if (PreHandledNum) { + if (PrevHandledNum) { Register Step; // Optimize for constant VLEN. if (auto VLEN = STI.getRealVLen()) { - int64_t Offset = *VLEN / 8 * PreHandledNum; + int64_t Offset = *VLEN / 8 * PrevHandledNum; Step = MRI.createVirtualRegister(&RISCV::GPRRegClass); STI.getInstrInfo()->movImm(MBB, II, DL, Step, Offset); } else { @@ -457,15 +458,21 @@ void RISCVRegisterInfo::lowerSegmentSpillReload(MachineBasicBlock::iterator II, VLENB = MRI.createVirtualRegister(&RISCV::GPRRegClass); BuildMI(MBB, II, DL, TII->get(RISCV::PseudoReadVLENB), VLENB); } - uint32_t ShiftAmount = Log2_32(PreHandledNum); - if (ShiftAmount == 0) - Step = VLENB; - else { - Step = MRI.createVirtualRegister(&RISCV::GPRRegClass); - BuildMI(MBB, II, DL, TII->get(RISCV::SLLI), Step) - .addReg(VLENB, getKillRegState(IsLast)) - .addImm(ShiftAmount); + uint32_t ShiftAmount = Log2_32(PrevHandledNum); + // To avoid using an extra register, we shift the VLENB register and + // remember how much it has been shifted. We can then use relative + // shifts to adjust to the desired shift amount. + if (VLENBShift > ShiftAmount) { + BuildMI(MBB, II, DL, TII->get(RISCV::SRLI), VLENB) + .addReg(VLENB, RegState::Kill) + .addImm(VLENBShift - ShiftAmount); + } else if (VLENBShift < ShiftAmount) { + BuildMI(MBB, II, DL, TII->get(RISCV::SLLI), VLENB) + .addReg(VLENB, RegState::Kill) + .addImm(ShiftAmount - VLENBShift); } + VLENBShift = ShiftAmount; + Step = VLENB; } BuildMI(MBB, II, DL, TII->get(RISCV::ADD), NewBase) @@ -489,7 +496,7 @@ void RISCVRegisterInfo::lowerSegmentSpillReload(MachineBasicBlock::iterator II, if (IsSpill) MIB.addReg(Reg, RegState::Implicit); - PreHandledNum = RegNumHandled; + PrevHandledNum = RegNumHandled; RegEncoding += RegNumHandled; I += RegNumHandled; } |
