nils.hoelscher
/
llvm-for-llvmta
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity
llvm-for-llvmta/lib/Target/AArch64/GISel/AArch64PostLegalizerLowerin...

705 lines
25 KiB
C++
Raw Normal View History

first commit
2022-04-25 10:02:23 +02:00
//=== AArch64PostLegalizerLowering.cpp --------------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
///
/// \file
/// Post-legalization lowering for instructions.
///
/// This is used to offload pattern matching from the selector.
///
/// For example, this combiner will notice that a G_SHUFFLE_VECTOR is actually
/// a G_ZIP, G_UZP, etc.
///
/// General optimization combines should be handled by either the
/// AArch64PostLegalizerCombiner or the AArch64PreLegalizerCombiner.
///
//===----------------------------------------------------------------------===//
#include "AArch64TargetMachine.h"
#include "AArch64GlobalISelUtils.h"
#include "MCTargetDesc/AArch64MCTargetDesc.h"
#include "llvm/CodeGen/GlobalISel/Combiner.h"
#include "llvm/CodeGen/GlobalISel/CombinerHelper.h"
#include "llvm/CodeGen/GlobalISel/CombinerInfo.h"
#include "llvm/CodeGen/GlobalISel/MIPatternMatch.h"
#include "llvm/CodeGen/GlobalISel/MachineIRBuilder.h"
#include "llvm/CodeGen/GlobalISel/Utils.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetOpcodes.h"
#include "llvm/CodeGen/TargetPassConfig.h"
#include "llvm/InitializePasses.h"
#include "llvm/Support/Debug.h"
#define DEBUG_TYPE "aarch64-postlegalizer-lowering"
using namespace llvm;
using namespace MIPatternMatch;
using namespace AArch64GISelUtils;
/// Represents a pseudo instruction which replaces a G_SHUFFLE_VECTOR.
///
/// Used for matching target-supported shuffles before codegen.
struct ShuffleVectorPseudo {
unsigned Opc; ///< Opcode for the instruction. (E.g. G_ZIP1)
Register Dst; ///< Destination register.
SmallVector<SrcOp, 2> SrcOps; ///< Source registers.
ShuffleVectorPseudo(unsigned Opc, Register Dst,
std::initializer_list<SrcOp> SrcOps)
: Opc(Opc), Dst(Dst), SrcOps(SrcOps){};
ShuffleVectorPseudo() {}
};
/// Check if a vector shuffle corresponds to a REV instruction with the
/// specified blocksize.
static bool isREVMask(ArrayRef<int> M, unsigned EltSize, unsigned NumElts,
unsigned BlockSize) {
assert((BlockSize == 16 || BlockSize == 32 || BlockSize == 64) &&
"Only possible block sizes for REV are: 16, 32, 64");
assert(EltSize != 64 && "EltSize cannot be 64 for REV mask.");
unsigned BlockElts = M[0] + 1;
// If the first shuffle index is UNDEF, be optimistic.
if (M[0] < 0)
BlockElts = BlockSize / EltSize;
if (BlockSize <= EltSize || BlockSize != BlockElts * EltSize)
return false;
for (unsigned i = 0; i < NumElts; ++i) {
// Ignore undef indices.
if (M[i] < 0)
continue;
if (static_cast<unsigned>(M[i]) !=
(i - i % BlockElts) + (BlockElts - 1 - i % BlockElts))
return false;
}
return true;
}
/// Determines if \p M is a shuffle vector mask for a TRN of \p NumElts.
/// Whether or not G_TRN1 or G_TRN2 should be used is stored in \p WhichResult.
static bool isTRNMask(ArrayRef<int> M, unsigned NumElts,
unsigned &WhichResult) {
if (NumElts % 2 != 0)
return false;
WhichResult = (M[0] == 0 ? 0 : 1);
for (unsigned i = 0; i < NumElts; i += 2) {
if ((M[i] >= 0 && static_cast<unsigned>(M[i]) != i + WhichResult) ||
(M[i + 1] >= 0 &&
static_cast<unsigned>(M[i + 1]) != i + NumElts + WhichResult))
return false;
}
return true;
}
/// Check if a G_EXT instruction can handle a shuffle mask \p M when the vector
/// sources of the shuffle are different.
static Optional<std::pair<bool, uint64_t>> getExtMask(ArrayRef<int> M,
unsigned NumElts) {
// Look for the first non-undef element.
auto FirstRealElt = find_if(M, [](int Elt) { return Elt >= 0; });
if (FirstRealElt == M.end())
return None;
// Use APInt to handle overflow when calculating expected element.
unsigned MaskBits = APInt(32, NumElts * 2).logBase2();
APInt ExpectedElt = APInt(MaskBits, *FirstRealElt + 1);
// The following shuffle indices must be the successive elements after the
// first real element.
if (any_of(
make_range(std::next(FirstRealElt), M.end()),
[&ExpectedElt](int Elt) { return Elt != ExpectedElt++ && Elt >= 0; }))
return None;
// The index of an EXT is the first element if it is not UNDEF.
// Watch out for the beginning UNDEFs. The EXT index should be the expected
// value of the first element. E.g.
// <-1, -1, 3, ...> is treated as <1, 2, 3, ...>.
// <-1, -1, 0, 1, ...> is treated as <2*NumElts-2, 2*NumElts-1, 0, 1, ...>.
// ExpectedElt is the last mask index plus 1.
uint64_t Imm = ExpectedElt.getZExtValue();
bool ReverseExt = false;
// There are two difference cases requiring to reverse input vectors.
// For example, for vector <4 x i32> we have the following cases,
// Case 1: shufflevector(<4 x i32>,<4 x i32>,<-1, -1, -1, 0>)
// Case 2: shufflevector(<4 x i32>,<4 x i32>,<-1, -1, 7, 0>)
// For both cases, we finally use mask <5, 6, 7, 0>, which requires
// to reverse two input vectors.
if (Imm < NumElts)
ReverseExt = true;
else
Imm -= NumElts;
return std::make_pair(ReverseExt, Imm);
}
/// Determines if \p M is a shuffle vector mask for a UZP of \p NumElts.
/// Whether or not G_UZP1 or G_UZP2 should be used is stored in \p WhichResult.
static bool isUZPMask(ArrayRef<int> M, unsigned NumElts,
unsigned &WhichResult) {
WhichResult = (M[0] == 0 ? 0 : 1);
for (unsigned i = 0; i != NumElts; ++i) {
// Skip undef indices.
if (M[i] < 0)
continue;
if (static_cast<unsigned>(M[i]) != 2 * i + WhichResult)
return false;
}
return true;
}
/// \return true if \p M is a zip mask for a shuffle vector of \p NumElts.
/// Whether or not G_ZIP1 or G_ZIP2 should be used is stored in \p WhichResult.
static bool isZipMask(ArrayRef<int> M, unsigned NumElts,
unsigned &WhichResult) {
if (NumElts % 2 != 0)
return false;
// 0 means use ZIP1, 1 means use ZIP2.
WhichResult = (M[0] == 0 ? 0 : 1);
unsigned Idx = WhichResult * NumElts / 2;
for (unsigned i = 0; i != NumElts; i += 2) {
if ((M[i] >= 0 && static_cast<unsigned>(M[i]) != Idx) ||
(M[i + 1] >= 0 && static_cast<unsigned>(M[i + 1]) != Idx + NumElts))
return false;
Idx += 1;
}
return true;
}
/// \return true if a G_SHUFFLE_VECTOR instruction \p MI can be replaced with a
/// G_REV instruction. Returns the appropriate G_REV opcode in \p Opc.
static bool matchREV(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
ArrayRef<int> ShuffleMask = MI.getOperand(3).getShuffleMask();
Register Dst = MI.getOperand(0).getReg();
Register Src = MI.getOperand(1).getReg();
LLT Ty = MRI.getType(Dst);
unsigned EltSize = Ty.getScalarSizeInBits();
// Element size for a rev cannot be 64.
if (EltSize == 64)
return false;
unsigned NumElts = Ty.getNumElements();
// Try to produce G_REV64
if (isREVMask(ShuffleMask, EltSize, NumElts, 64)) {
MatchInfo = ShuffleVectorPseudo(AArch64::G_REV64, Dst, {Src});
return true;
}
// TODO: Produce G_REV32 and G_REV16 once we have proper legalization support.
// This should be identical to above, but with a constant 32 and constant
// 16.
return false;
}
/// \return true if a G_SHUFFLE_VECTOR instruction \p MI can be replaced with
/// a G_TRN1 or G_TRN2 instruction.
static bool matchTRN(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
unsigned WhichResult;
ArrayRef<int> ShuffleMask = MI.getOperand(3).getShuffleMask();
Register Dst = MI.getOperand(0).getReg();
unsigned NumElts = MRI.getType(Dst).getNumElements();
if (!isTRNMask(ShuffleMask, NumElts, WhichResult))
return false;
unsigned Opc = (WhichResult == 0) ? AArch64::G_TRN1 : AArch64::G_TRN2;
Register V1 = MI.getOperand(1).getReg();
Register V2 = MI.getOperand(2).getReg();
MatchInfo = ShuffleVectorPseudo(Opc, Dst, {V1, V2});
return true;
}
/// \return true if a G_SHUFFLE_VECTOR instruction \p MI can be replaced with
/// a G_UZP1 or G_UZP2 instruction.
///
/// \param [in] MI - The shuffle vector instruction.
/// \param [out] MatchInfo - Either G_UZP1 or G_UZP2 on success.
static bool matchUZP(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
unsigned WhichResult;
ArrayRef<int> ShuffleMask = MI.getOperand(3).getShuffleMask();
Register Dst = MI.getOperand(0).getReg();
unsigned NumElts = MRI.getType(Dst).getNumElements();
if (!isUZPMask(ShuffleMask, NumElts, WhichResult))
return false;
unsigned Opc = (WhichResult == 0) ? AArch64::G_UZP1 : AArch64::G_UZP2;
Register V1 = MI.getOperand(1).getReg();
Register V2 = MI.getOperand(2).getReg();
MatchInfo = ShuffleVectorPseudo(Opc, Dst, {V1, V2});
return true;
}
static bool matchZip(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
unsigned WhichResult;
ArrayRef<int> ShuffleMask = MI.getOperand(3).getShuffleMask();
Register Dst = MI.getOperand(0).getReg();
unsigned NumElts = MRI.getType(Dst).getNumElements();
if (!isZipMask(ShuffleMask, NumElts, WhichResult))
return false;
unsigned Opc = (WhichResult == 0) ? AArch64::G_ZIP1 : AArch64::G_ZIP2;
Register V1 = MI.getOperand(1).getReg();
Register V2 = MI.getOperand(2).getReg();
MatchInfo = ShuffleVectorPseudo(Opc, Dst, {V1, V2});
return true;
}
/// Helper function for matchDup.
static bool matchDupFromInsertVectorElt(int Lane, MachineInstr &MI,
MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
if (Lane != 0)
return false;
// Try to match a vector splat operation into a dup instruction.
// We're looking for this pattern:
//
// %scalar:gpr(s64) = COPY $x0
// %undef:fpr(<2 x s64>) = G_IMPLICIT_DEF
// %cst0:gpr(s32) = G_CONSTANT i32 0
// %zerovec:fpr(<2 x s32>) = G_BUILD_VECTOR %cst0(s32), %cst0(s32)
// %ins:fpr(<2 x s64>) = G_INSERT_VECTOR_ELT %undef, %scalar(s64), %cst0(s32)
// %splat:fpr(<2 x s64>) = G_SHUFFLE_VECTOR %ins(<2 x s64>), %undef, %zerovec(<2 x s32>)
//
// ...into:
// %splat = G_DUP %scalar
// Begin matching the insert.
auto *InsMI = getOpcodeDef(TargetOpcode::G_INSERT_VECTOR_ELT,
MI.getOperand(1).getReg(), MRI);
if (!InsMI)
return false;
// Match the undef vector operand.
if (!getOpcodeDef(TargetOpcode::G_IMPLICIT_DEF, InsMI->getOperand(1).getReg(),
MRI))
return false;
// Match the index constant 0.
if (!mi_match(InsMI->getOperand(3).getReg(), MRI, m_ZeroInt()))
return false;
MatchInfo = ShuffleVectorPseudo(AArch64::G_DUP, MI.getOperand(0).getReg(),
{InsMI->getOperand(2).getReg()});
return true;
}
/// Helper function for matchDup.
static bool matchDupFromBuildVector(int Lane, MachineInstr &MI,
MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(Lane >= 0 && "Expected positive lane?");
// Test if the LHS is a BUILD_VECTOR. If it is, then we can just reference the
// lane's definition directly.
auto *BuildVecMI = getOpcodeDef(TargetOpcode::G_BUILD_VECTOR,
MI.getOperand(1).getReg(), MRI);
if (!BuildVecMI)
return false;
Register Reg = BuildVecMI->getOperand(Lane + 1).getReg();
MatchInfo =
ShuffleVectorPseudo(AArch64::G_DUP, MI.getOperand(0).getReg(), {Reg});
return true;
}
static bool matchDup(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
auto MaybeLane = getSplatIndex(MI);
if (!MaybeLane)
return false;
int Lane = *MaybeLane;
// If this is undef splat, generate it via "just" vdup, if possible.
if (Lane < 0)
Lane = 0;
if (matchDupFromInsertVectorElt(Lane, MI, MRI, MatchInfo))
return true;
if (matchDupFromBuildVector(Lane, MI, MRI, MatchInfo))
return true;
return false;
}
static bool matchEXT(MachineInstr &MI, MachineRegisterInfo &MRI,
ShuffleVectorPseudo &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
Register Dst = MI.getOperand(0).getReg();
auto ExtInfo = getExtMask(MI.getOperand(3).getShuffleMask(),
MRI.getType(Dst).getNumElements());
if (!ExtInfo)
return false;
bool ReverseExt;
uint64_t Imm;
std::tie(ReverseExt, Imm) = *ExtInfo;
Register V1 = MI.getOperand(1).getReg();
Register V2 = MI.getOperand(2).getReg();
if (ReverseExt)
std::swap(V1, V2);
uint64_t ExtFactor = MRI.getType(V1).getScalarSizeInBits() / 8;
Imm *= ExtFactor;
MatchInfo = ShuffleVectorPseudo(AArch64::G_EXT, Dst, {V1, V2, Imm});
return true;
}
/// Replace a G_SHUFFLE_VECTOR instruction with a pseudo.
/// \p Opc is the opcode to use. \p MI is the G_SHUFFLE_VECTOR.
static bool applyShuffleVectorPseudo(MachineInstr &MI,
ShuffleVectorPseudo &MatchInfo) {
MachineIRBuilder MIRBuilder(MI);
MIRBuilder.buildInstr(MatchInfo.Opc, {MatchInfo.Dst}, MatchInfo.SrcOps);
MI.eraseFromParent();
return true;
}
/// Replace a G_SHUFFLE_VECTOR instruction with G_EXT.
/// Special-cased because the constant operand must be emitted as a G_CONSTANT
/// for the imported tablegen patterns to work.
static bool applyEXT(MachineInstr &MI, ShuffleVectorPseudo &MatchInfo) {
MachineIRBuilder MIRBuilder(MI);
// Tablegen patterns expect an i32 G_CONSTANT as the final op.
auto Cst =
MIRBuilder.buildConstant(LLT::scalar(32), MatchInfo.SrcOps[2].getImm());
MIRBuilder.buildInstr(MatchInfo.Opc, {MatchInfo.Dst},
{MatchInfo.SrcOps[0], MatchInfo.SrcOps[1], Cst});
MI.eraseFromParent();
return true;
}
/// isVShiftRImm - Check if this is a valid vector for the immediate
/// operand of a vector shift right operation. The value must be in the range:
/// 1 <= Value <= ElementBits for a right shift.
static bool isVShiftRImm(Register Reg, MachineRegisterInfo &MRI, LLT Ty,
int64_t &Cnt) {
assert(Ty.isVector() && "vector shift count is not a vector type");
MachineInstr *MI = MRI.getVRegDef(Reg);
auto Cst = getBuildVectorConstantSplat(*MI, MRI);
if (!Cst)
return false;
Cnt = *Cst;
int64_t ElementBits = Ty.getScalarSizeInBits();
return Cnt >= 1 && Cnt <= ElementBits;
}
/// Match a vector G_ASHR or G_LSHR with a valid immediate shift.
static bool matchVAshrLshrImm(MachineInstr &MI, MachineRegisterInfo &MRI,
int64_t &Imm) {
assert(MI.getOpcode() == TargetOpcode::G_ASHR ||
MI.getOpcode() == TargetOpcode::G_LSHR);
LLT Ty = MRI.getType(MI.getOperand(1).getReg());
if (!Ty.isVector())
return false;
return isVShiftRImm(MI.getOperand(2).getReg(), MRI, Ty, Imm);
}
static bool applyVAshrLshrImm(MachineInstr &MI, MachineRegisterInfo &MRI,
int64_t &Imm) {
unsigned Opc = MI.getOpcode();
assert(Opc == TargetOpcode::G_ASHR || Opc == TargetOpcode::G_LSHR);
unsigned NewOpc =
Opc == TargetOpcode::G_ASHR ? AArch64::G_VASHR : AArch64::G_VLSHR;
MachineIRBuilder MIB(MI);
auto ImmDef = MIB.buildConstant(LLT::scalar(32), Imm);
MIB.buildInstr(NewOpc, {MI.getOperand(0)}, {MI.getOperand(1), ImmDef});
MI.eraseFromParent();
return true;
}
/// Determine if it is possible to modify the \p RHS and predicate \p P of a
/// G_ICMP instruction such that the right-hand side is an arithmetic immediate.
///
/// \returns A pair containing the updated immediate and predicate which may
/// be used to optimize the instruction.
///
/// \note This assumes that the comparison has been legalized.
Optional<std::pair<uint64_t, CmpInst::Predicate>>
tryAdjustICmpImmAndPred(Register RHS, CmpInst::Predicate P,
const MachineRegisterInfo &MRI) {
const auto &Ty = MRI.getType(RHS);
if (Ty.isVector())
return None;
unsigned Size = Ty.getSizeInBits();
assert((Size == 32 || Size == 64) && "Expected 32 or 64 bit compare only?");
// If the RHS is not a constant, or the RHS is already a valid arithmetic
// immediate, then there is nothing to change.
auto ValAndVReg = getConstantVRegValWithLookThrough(RHS, MRI);
if (!ValAndVReg)
return None;
uint64_t C = ValAndVReg->Value.getZExtValue();
if (isLegalArithImmed(C))
return None;
// We have a non-arithmetic immediate. Check if adjusting the immediate and
// adjusting the predicate will result in a legal arithmetic immediate.
switch (P) {
default:
return None;
case CmpInst::ICMP_SLT:
case CmpInst::ICMP_SGE:
// Check for
//
// x slt c => x sle c - 1
// x sge c => x sgt c - 1
//
// When c is not the smallest possible negative number.
if ((Size == 64 && static_cast<int64_t>(C) == INT64_MIN) ||
(Size == 32 && static_cast<int32_t>(C) == INT32_MIN))
return None;
P = (P == CmpInst::ICMP_SLT) ? CmpInst::ICMP_SLE : CmpInst::ICMP_SGT;
C -= 1;
break;
case CmpInst::ICMP_ULT:
case CmpInst::ICMP_UGE:
// Check for
//
// x ult c => x ule c - 1
// x uge c => x ugt c - 1
//
// When c is not zero.
if (C == 0)
return None;
P = (P == CmpInst::ICMP_ULT) ? CmpInst::ICMP_ULE : CmpInst::ICMP_UGT;
C -= 1;
break;
case CmpInst::ICMP_SLE:
case CmpInst::ICMP_SGT:
// Check for
//
// x sle c => x slt c + 1
// x sgt c => s sge c + 1
//
// When c is not the largest possible signed integer.
if ((Size == 32 && static_cast<int32_t>(C) == INT32_MAX) ||
(Size == 64 && static_cast<int64_t>(C) == INT64_MAX))
return None;
P = (P == CmpInst::ICMP_SLE) ? CmpInst::ICMP_SLT : CmpInst::ICMP_SGE;
C += 1;
break;
case CmpInst::ICMP_ULE:
case CmpInst::ICMP_UGT:
// Check for
//
// x ule c => x ult c + 1
// x ugt c => s uge c + 1
//
// When c is not the largest possible unsigned integer.
if ((Size == 32 && static_cast<uint32_t>(C) == UINT32_MAX) ||
(Size == 64 && C == UINT64_MAX))
return None;
P = (P == CmpInst::ICMP_ULE) ? CmpInst::ICMP_ULT : CmpInst::ICMP_UGE;
C += 1;
break;
}
// Check if the new constant is valid, and return the updated constant and
// predicate if it is.
if (Size == 32)
C = static_cast<uint32_t>(C);
if (!isLegalArithImmed(C))
return None;
return {{C, P}};
}
/// Determine whether or not it is possible to update the RHS and predicate of
/// a G_ICMP instruction such that the RHS will be selected as an arithmetic
/// immediate.
///
/// \p MI - The G_ICMP instruction
/// \p MatchInfo - The new RHS immediate and predicate on success
///
/// See tryAdjustICmpImmAndPred for valid transformations.
bool matchAdjustICmpImmAndPred(
MachineInstr &MI, const MachineRegisterInfo &MRI,
std::pair<uint64_t, CmpInst::Predicate> &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_ICMP);
Register RHS = MI.getOperand(3).getReg();
auto Pred = static_cast<CmpInst::Predicate>(MI.getOperand(1).getPredicate());
if (auto MaybeNewImmAndPred = tryAdjustICmpImmAndPred(RHS, Pred, MRI)) {
MatchInfo = *MaybeNewImmAndPred;
return true;
}
return false;
}
bool applyAdjustICmpImmAndPred(
MachineInstr &MI, std::pair<uint64_t, CmpInst::Predicate> &MatchInfo,
MachineIRBuilder &MIB, GISelChangeObserver &Observer) {
MIB.setInstrAndDebugLoc(MI);
MachineOperand &RHS = MI.getOperand(3);
MachineRegisterInfo &MRI = *MIB.getMRI();
auto Cst = MIB.buildConstant(MRI.cloneVirtualRegister(RHS.getReg()),
MatchInfo.first);
Observer.changingInstr(MI);
RHS.setReg(Cst->getOperand(0).getReg());
MI.getOperand(1).setPredicate(MatchInfo.second);
Observer.changedInstr(MI);
return true;
}
bool matchDupLane(MachineInstr &MI, MachineRegisterInfo &MRI,
std::pair<unsigned, int> &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
Register Src1Reg = MI.getOperand(1).getReg();
const LLT SrcTy = MRI.getType(Src1Reg);
const LLT DstTy = MRI.getType(MI.getOperand(0).getReg());
auto LaneIdx = getSplatIndex(MI);
if (!LaneIdx)
return false;
// The lane idx should be within the first source vector.
if (*LaneIdx >= SrcTy.getNumElements())
return false;
if (DstTy != SrcTy)
return false;
LLT ScalarTy = SrcTy.getElementType();
unsigned ScalarSize = ScalarTy.getSizeInBits();
unsigned Opc = 0;
switch (SrcTy.getNumElements()) {
case 2:
if (ScalarSize == 64)
Opc = AArch64::G_DUPLANE64;
break;
case 4:
if (ScalarSize == 32)
Opc = AArch64::G_DUPLANE32;
break;
case 8:
if (ScalarSize == 16)
Opc = AArch64::G_DUPLANE16;
break;
case 16:
if (ScalarSize == 8)
Opc = AArch64::G_DUPLANE8;
break;
default:
break;
}
if (!Opc)
return false;
MatchInfo.first = Opc;
MatchInfo.second = *LaneIdx;
return true;
}
bool applyDupLane(MachineInstr &MI, MachineRegisterInfo &MRI,
MachineIRBuilder &B, std::pair<unsigned, int> &MatchInfo) {
assert(MI.getOpcode() == TargetOpcode::G_SHUFFLE_VECTOR);
B.setInstrAndDebugLoc(MI);
auto Lane = B.buildConstant(LLT::scalar(64), MatchInfo.second);
B.buildInstr(MatchInfo.first, {MI.getOperand(0).getReg()},
{MI.getOperand(1).getReg(), Lane});
MI.eraseFromParent();
return true;
}
#define AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_DEPS
#include "AArch64GenPostLegalizeGILowering.inc"
#undef AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_DEPS
namespace {
#define AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_H
#include "AArch64GenPostLegalizeGILowering.inc"
#undef AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_H
class AArch64PostLegalizerLoweringInfo : public CombinerInfo {
public:
AArch64GenPostLegalizerLoweringHelperRuleConfig GeneratedRuleCfg;
AArch64PostLegalizerLoweringInfo(bool OptSize, bool MinSize)
: CombinerInfo(/*AllowIllegalOps*/ true, /*ShouldLegalizeIllegal*/ false,
/*LegalizerInfo*/ nullptr, /*OptEnabled = */ true, OptSize,
MinSize) {
if (!GeneratedRuleCfg.parseCommandLineOption())
report_fatal_error("Invalid rule identifier");
}
virtual bool combine(GISelChangeObserver &Observer, MachineInstr &MI,
MachineIRBuilder &B) const override;
};
bool AArch64PostLegalizerLoweringInfo::combine(GISelChangeObserver &Observer,
MachineInstr &MI,
MachineIRBuilder &B) const {
CombinerHelper Helper(Observer, B);
AArch64GenPostLegalizerLoweringHelper Generated(GeneratedRuleCfg);
return Generated.tryCombineAll(Observer, MI, B, Helper);
}
#define AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_CPP
#include "AArch64GenPostLegalizeGILowering.inc"
#undef AARCH64POSTLEGALIZERLOWERINGHELPER_GENCOMBINERHELPER_CPP
class AArch64PostLegalizerLowering : public MachineFunctionPass {
public:
static char ID;
AArch64PostLegalizerLowering();
StringRef getPassName() const override {
return "AArch64PostLegalizerLowering";
}
bool runOnMachineFunction(MachineFunction &MF) override;
void getAnalysisUsage(AnalysisUsage &AU) const override;
};
} // end anonymous namespace
void AArch64PostLegalizerLowering::getAnalysisUsage(AnalysisUsage &AU) const {
AU.addRequired<TargetPassConfig>();
AU.setPreservesCFG();
getSelectionDAGFallbackAnalysisUsage(AU);
MachineFunctionPass::getAnalysisUsage(AU);
}
AArch64PostLegalizerLowering::AArch64PostLegalizerLowering()
: MachineFunctionPass(ID) {
initializeAArch64PostLegalizerLoweringPass(*PassRegistry::getPassRegistry());
}
bool AArch64PostLegalizerLowering::runOnMachineFunction(MachineFunction &MF) {
if (MF.getProperties().hasProperty(
MachineFunctionProperties::Property::FailedISel))
return false;
assert(MF.getProperties().hasProperty(
MachineFunctionProperties::Property::Legalized) &&
"Expected a legalized function?");
auto *TPC = &getAnalysis<TargetPassConfig>();
const Function &F = MF.getFunction();
AArch64PostLegalizerLoweringInfo PCInfo(F.hasOptSize(), F.hasMinSize());
Combiner C(PCInfo, TPC);
return C.combineMachineInstrs(MF, /*CSEInfo*/ nullptr);
}
char AArch64PostLegalizerLowering::ID = 0;
INITIALIZE_PASS_BEGIN(AArch64PostLegalizerLowering, DEBUG_TYPE,
"Lower AArch64 MachineInstrs after legalization", false,
false)
INITIALIZE_PASS_DEPENDENCY(TargetPassConfig)
INITIALIZE_PASS_END(AArch64PostLegalizerLowering, DEBUG_TYPE,
"Lower AArch64 MachineInstrs after legalization", false,
false)
namespace llvm {
FunctionPass *createAArch64PostLegalizerLowering() {
return new AArch64PostLegalizerLowering();
}
} // end namespace llvm