Refactoring and enhancement to FMA combine.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@235344 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Olivier Sallenave 2015-04-20 20:29:40 +00:00
parent d485ac5538
commit d153d3d8cc
3 changed files with 556 additions and 202 deletions

View File

@ -309,6 +309,9 @@ namespace {
SDValue visitMSTORE(SDNode *N);
SDValue visitFP_TO_FP16(SDNode *N);
SDValue visitFADDForFMACombine(SDNode *N);
SDValue visitFSUBForFMACombine(SDNode *N);
SDValue XformToShuffleWithZero(SDNode *N);
SDValue ReassociateOps(unsigned Opc, SDLoc DL, SDValue LHS, SDValue RHS);
@ -7062,20 +7065,44 @@ ConstantFoldBITCASTofBUILD_VECTOR(SDNode *BV, EVT DstEltVT) {
return DAG.getNode(ISD::BUILD_VECTOR, SDLoc(BV), VT, Ops);
}
// Attempt different variants of (fadd (fmul a, b), c) -> fma or fmad
static SDValue performFaddFmulCombines(unsigned FusedOpcode,
bool Aggressive,
SDNode *N,
const TargetLowering &TLI,
SelectionDAG &DAG) {
/// Try to perform FMA combining on a given FADD node.
SDValue DAGCombiner::visitFADDForFMACombine(SDNode *N) {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
EVT VT = N->getValueType(0);
SDLoc SL(N);
const TargetOptions &Options = DAG.getTarget().Options;
bool UnsafeFPMath = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
Options.UnsafeFPMath);
// Floating-point multiply-add with intermediate rounding.
bool HasFMAD = (LegalOperations &&
TLI.isOperationLegal(ISD::FMAD, VT));
// Floating-point multiply-add without intermediate rounding.
bool HasFMA = ((!LegalOperations ||
TLI.isOperationLegalOrCustom(ISD::FMA, VT)) &&
TLI.isFMAFasterThanFMulAndFAdd(VT) &&
UnsafeFPMath);
// No valid opcode, do not combine.
if (!HasFMAD && !HasFMA)
return SDValue();
// Always prefer FMAD to FMA for precision.
unsigned int PreferredFusedOpcode = HasFMAD ? ISD::FMAD : ISD::FMA;
bool Aggressive = TLI.enableAggressiveFMAFusion(VT);
bool LookThroughFPExt = TLI.isFPExtFree(VT);
// fold (fadd (fmul x, y), z) -> (fma x, y, z)
if (N0.getOpcode() == ISD::FMUL &&
(Aggressive || N0->hasOneUse())) {
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1), N1);
}
@ -7083,53 +7110,180 @@ static SDValue performFaddFmulCombines(unsigned FusedOpcode,
// Note: Commutes FADD operands.
if (N1.getOpcode() == ISD::FMUL &&
(Aggressive || N1->hasOneUse())) {
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N1.getOperand(0), N1.getOperand(1), N0);
}
// Look through FP_EXTEND nodes to do more combining.
if (UnsafeFPMath && LookThroughFPExt) {
// fold (fadd (fpext (fmul x, y)), z) -> (fma (fpext x), (fpext y), z)
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(1)), N1);
}
// fold (fadd x, (fpext (fmul y, z))) -> (fma (fpext y), (fpext z), x)
// Note: Commutes FADD operands.
if (N1.getOpcode() == ISD::FP_EXTEND) {
SDValue N10 = N1.getOperand(0);
if (N10.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N10.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N10.getOperand(1)), N0);
}
}
// More folding opportunities when target permits.
if (Aggressive) {
if ((UnsafeFPMath || HasFMAD) && Aggressive) {
// fold (fadd (fma x, y, (fmul u, v)), z) -> (fma x, y (fma u, v, z))
if (N0.getOpcode() == ISD::FMA &&
if (N0.getOpcode() == PreferredFusedOpcode &&
N0.getOperand(2).getOpcode() == ISD::FMUL) {
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1),
DAG.getNode(FusedOpcode, SDLoc(N), VT,
DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(2).getOperand(0),
N0.getOperand(2).getOperand(1),
N1));
}
// fold (fadd x, (fma y, z, (fmul u, v)) -> (fma y, z (fma u, v, x))
if (N1->getOpcode() == ISD::FMA &&
if (N1->getOpcode() == PreferredFusedOpcode &&
N1.getOperand(2).getOpcode() == ISD::FMUL) {
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N1.getOperand(0), N1.getOperand(1),
DAG.getNode(FusedOpcode, SDLoc(N), VT,
DAG.getNode(PreferredFusedOpcode, SL, VT,
N1.getOperand(2).getOperand(0),
N1.getOperand(2).getOperand(1),
N0));
}
if (LookThroughFPExt) {
// fold (fadd (fma x, y, (fpext (fmul u, v))), z)
// -> (fma x, y, (fma (fpext u), (fpext v), z))
auto FoldFAddFMAFPExtFMul = [&] (
SDValue X, SDValue Y, SDValue U, SDValue V, SDValue Z) {
return DAG.getNode(PreferredFusedOpcode, SL, VT, X, Y,
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT, U),
DAG.getNode(ISD::FP_EXTEND, SL, VT, V),
Z));
};
if (N0.getOpcode() == PreferredFusedOpcode) {
SDValue N02 = N0.getOperand(2);
if (N02.getOpcode() == ISD::FP_EXTEND) {
SDValue N020 = N02.getOperand(0);
if (N020.getOpcode() == ISD::FMUL)
return FoldFAddFMAFPExtFMul(N0.getOperand(0), N0.getOperand(1),
N020.getOperand(0), N020.getOperand(1),
N1);
}
}
// fold (fadd (fpext (fma x, y, (fmul u, v))), z)
// -> (fma (fpext x), (fpext y), (fma (fpext u), (fpext v), z))
// FIXME: This turns two single-precision and one double-precision
// operation into two double-precision operations, which might not be
// interesting for all targets, especially GPUs.
auto FoldFAddFPExtFMAFMul = [&] (
SDValue X, SDValue Y, SDValue U, SDValue V, SDValue Z) {
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT, X),
DAG.getNode(ISD::FP_EXTEND, SL, VT, Y),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT, U),
DAG.getNode(ISD::FP_EXTEND, SL, VT, V),
Z));
};
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == PreferredFusedOpcode) {
SDValue N002 = N00.getOperand(2);
if (N002.getOpcode() == ISD::FMUL)
return FoldFAddFPExtFMAFMul(N00.getOperand(0), N00.getOperand(1),
N002.getOperand(0), N002.getOperand(1),
N1);
}
}
// fold (fadd x, (fma y, z, (fpext (fmul u, v)))
// -> (fma y, z, (fma (fpext u), (fpext v), x))
if (N1.getOpcode() == PreferredFusedOpcode) {
SDValue N12 = N1.getOperand(2);
if (N12.getOpcode() == ISD::FP_EXTEND) {
SDValue N120 = N12.getOperand(0);
if (N120.getOpcode() == ISD::FMUL)
return FoldFAddFMAFPExtFMul(N1.getOperand(0), N1.getOperand(1),
N120.getOperand(0), N120.getOperand(1),
N0);
}
}
// fold (fadd x, (fpext (fma y, z, (fmul u, v)))
// -> (fma (fpext y), (fpext z), (fma (fpext u), (fpext v), x))
// FIXME: This turns two single-precision and one double-precision
// operation into two double-precision operations, which might not be
// interesting for all targets, especially GPUs.
if (N1.getOpcode() == ISD::FP_EXTEND) {
SDValue N10 = N1.getOperand(0);
if (N10.getOpcode() == PreferredFusedOpcode) {
SDValue N102 = N10.getOperand(2);
if (N102.getOpcode() == ISD::FMUL)
return FoldFAddFPExtFMAFMul(N10.getOperand(0), N10.getOperand(1),
N102.getOperand(0), N102.getOperand(1),
N0);
}
}
}
}
return SDValue();
}
static SDValue performFsubFmulCombines(unsigned FusedOpcode,
bool Aggressive,
SDNode *N,
const TargetLowering &TLI,
SelectionDAG &DAG) {
/// Try to perform FMA combining on a given FSUB node.
SDValue DAGCombiner::visitFSUBForFMACombine(SDNode *N) {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
EVT VT = N->getValueType(0);
SDLoc SL(N);
const TargetOptions &Options = DAG.getTarget().Options;
bool UnsafeFPMath = (Options.AllowFPOpFusion == FPOpFusion::Fast ||
Options.UnsafeFPMath);
// Floating-point multiply-add with intermediate rounding.
bool HasFMAD = (LegalOperations &&
TLI.isOperationLegal(ISD::FMAD, VT));
// Floating-point multiply-add without intermediate rounding.
bool HasFMA = ((!LegalOperations ||
TLI.isOperationLegalOrCustom(ISD::FMA, VT)) &&
TLI.isFMAFasterThanFMulAndFAdd(VT) &&
UnsafeFPMath);
// No valid opcode, do not combine.
if (!HasFMAD && !HasFMA)
return SDValue();
// Always prefer FMAD to FMA for precision.
unsigned int PreferredFusedOpcode = HasFMAD ? ISD::FMAD : ISD::FMA;
bool Aggressive = TLI.enableAggressiveFMAFusion(VT);
bool LookThroughFPExt = TLI.isFPExtFree(VT);
// fold (fsub (fmul x, y), z) -> (fma x, y, (fneg z))
if (N0.getOpcode() == ISD::FMUL &&
(Aggressive || N0->hasOneUse())) {
return DAG.getNode(FusedOpcode, SL, VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1),
DAG.getNode(ISD::FNEG, SL, VT, N1));
}
@ -7138,7 +7292,7 @@ static SDValue performFsubFmulCombines(unsigned FusedOpcode,
// Note: Commutes FSUB operands.
if (N1.getOpcode() == ISD::FMUL &&
(Aggressive || N1->hasOneUse()))
return DAG.getNode(FusedOpcode, SL, VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
N1.getOperand(0)),
N1.getOperand(1), N0);
@ -7149,41 +7303,214 @@ static SDValue performFsubFmulCombines(unsigned FusedOpcode,
(Aggressive || (N0->hasOneUse() && N0.getOperand(0).hasOneUse()))) {
SDValue N00 = N0.getOperand(0).getOperand(0);
SDValue N01 = N0.getOperand(0).getOperand(1);
return DAG.getNode(FusedOpcode, SL, VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT, N00), N01,
DAG.getNode(ISD::FNEG, SL, VT, N1));
}
// Look through FP_EXTEND nodes to do more combining.
if (UnsafeFPMath && LookThroughFPExt) {
// fold (fsub (fpext (fmul x, y)), z)
// -> (fma (fpext x), (fpext y), (fneg z))
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(1)),
DAG.getNode(ISD::FNEG, SL, VT, N1));
}
// fold (fsub x, (fpext (fmul y, z)))
// -> (fma (fneg (fpext y)), (fpext z), x)
// Note: Commutes FSUB operands.
if (N1.getOpcode() == ISD::FP_EXTEND) {
SDValue N10 = N1.getOperand(0);
if (N10.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N10.getOperand(0))),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N10.getOperand(1)),
N0);
}
// fold (fsub (fpext (fneg (fmul, x, y))), z)
// -> (fneg (fma (fpext x), (fpext y), z))
// Note: This could be removed with appropriate canonicalization of the
// input expression into (fneg (fadd (fpext (fmul, x, y)), z). However, the
// orthogonal flags -fp-contract=fast and -enable-unsafe-fp-math prevent
// from implementing the canonicalization in visitFSUB.
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FNEG) {
SDValue N000 = N00.getOperand(0);
if (N000.getOpcode() == ISD::FMUL) {
return DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N000.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N000.getOperand(1)),
N1));
}
}
}
// fold (fsub (fneg (fpext (fmul, x, y))), z)
// -> (fneg (fma (fpext x)), (fpext y), z)
// Note: This could be removed with appropriate canonicalization of the
// input expression into (fneg (fadd (fpext (fmul, x, y)), z). However, the
// orthogonal flags -fp-contract=fast and -enable-unsafe-fp-math prevent
// from implementing the canonicalization in visitFSUB.
if (N0.getOpcode() == ISD::FNEG) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FP_EXTEND) {
SDValue N000 = N00.getOperand(0);
if (N000.getOpcode() == ISD::FMUL) {
return DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N000.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N000.getOperand(1)),
N1));
}
}
}
}
// More folding opportunities when target permits.
if (Aggressive) {
if ((UnsafeFPMath || HasFMAD) && Aggressive) {
// fold (fsub (fma x, y, (fmul u, v)), z)
// -> (fma x, y (fma u, v, (fneg z)))
if (N0.getOpcode() == FusedOpcode &&
if (N0.getOpcode() == PreferredFusedOpcode &&
N0.getOperand(2).getOpcode() == ISD::FMUL) {
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1),
DAG.getNode(FusedOpcode, SDLoc(N), VT,
DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(2).getOperand(0),
N0.getOperand(2).getOperand(1),
DAG.getNode(ISD::FNEG, SDLoc(N), VT,
DAG.getNode(ISD::FNEG, SL, VT,
N1)));
}
// fold (fsub x, (fma y, z, (fmul u, v)))
// -> (fma (fneg y), z, (fma (fneg u), v, x))
if (N1.getOpcode() == FusedOpcode &&
if (N1.getOpcode() == PreferredFusedOpcode &&
N1.getOperand(2).getOpcode() == ISD::FMUL) {
SDValue N20 = N1.getOperand(2).getOperand(0);
SDValue N21 = N1.getOperand(2).getOperand(1);
return DAG.getNode(FusedOpcode, SDLoc(N), VT,
DAG.getNode(ISD::FNEG, SDLoc(N), VT,
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
N1.getOperand(0)),
N1.getOperand(1),
DAG.getNode(FusedOpcode, SDLoc(N), VT,
DAG.getNode(ISD::FNEG, SDLoc(N), VT,
N20),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT, N20),
N21, N0));
}
if (LookThroughFPExt) {
// fold (fsub (fma x, y, (fpext (fmul u, v))), z)
// -> (fma x, y (fma (fpext u), (fpext v), (fneg z)))
if (N0.getOpcode() == PreferredFusedOpcode) {
SDValue N02 = N0.getOperand(2);
if (N02.getOpcode() == ISD::FP_EXTEND) {
SDValue N020 = N02.getOperand(0);
if (N020.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N020.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N020.getOperand(1)),
DAG.getNode(ISD::FNEG, SL, VT,
N1)));
}
}
// fold (fsub (fpext (fma x, y, (fmul u, v))), z)
// -> (fma (fpext x), (fpext y),
// (fma (fpext u), (fpext v), (fneg z)))
// FIXME: This turns two single-precision and one double-precision
// operation into two double-precision operations, which might not be
// interesting for all targets, especially GPUs.
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == PreferredFusedOpcode) {
SDValue N002 = N00.getOperand(2);
if (N002.getOpcode() == ISD::FMUL)
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N00.getOperand(1)),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N002.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N002.getOperand(1)),
DAG.getNode(ISD::FNEG, SL, VT,
N1)));
}
}
// fold (fsub x, (fma y, z, (fpext (fmul u, v))))
// -> (fma (fneg y), z, (fma (fneg (fpext u)), (fpext v), x))
if (N1.getOpcode() == PreferredFusedOpcode &&
N1.getOperand(2).getOpcode() == ISD::FP_EXTEND) {
SDValue N120 = N1.getOperand(2).getOperand(0);
if (N120.getOpcode() == ISD::FMUL) {
SDValue N1200 = N120.getOperand(0);
SDValue N1201 = N120.getOperand(1);
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT, N1.getOperand(0)),
N1.getOperand(1),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL,
VT, N1200)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N1201),
N0));
}
}
// fold (fsub x, (fpext (fma y, z, (fmul u, v))))
// -> (fma (fneg (fpext y)), (fpext z),
// (fma (fneg (fpext u)), (fpext v), x))
// FIXME: This turns two single-precision and one double-precision
// operation into two double-precision operations, which might not be
// interesting for all targets, especially GPUs.
if (N1.getOpcode() == ISD::FP_EXTEND &&
N1.getOperand(0).getOpcode() == PreferredFusedOpcode) {
SDValue N100 = N1.getOperand(0).getOperand(0);
SDValue N101 = N1.getOperand(0).getOperand(1);
SDValue N102 = N1.getOperand(0).getOperand(2);
if (N102.getOpcode() == ISD::FMUL) {
SDValue N1020 = N102.getOperand(0);
SDValue N1021 = N102.getOperand(1);
return DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N100)),
DAG.getNode(ISD::FP_EXTEND, SL, VT, N101),
DAG.getNode(PreferredFusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
DAG.getNode(ISD::FP_EXTEND, SL,
VT, N1020)),
DAG.getNode(ISD::FP_EXTEND, SL, VT,
N1021),
N0));
}
}
}
}
return SDValue();
@ -7327,55 +7654,11 @@ SDValue DAGCombiner::visitFADD(SDNode *N) {
}
} // enable-unsafe-fp-math
if (LegalOperations && TLI.isOperationLegal(ISD::FMAD, VT)) {
// Assume if there is an fmad instruction that it should be aggressively
// used.
if (SDValue Fused = performFaddFmulCombines(ISD::FMAD, true, N, TLI, DAG))
return Fused;
}
// FADD -> FMA combines:
if ((Options.AllowFPOpFusion == FPOpFusion::Fast || Options.UnsafeFPMath) &&
TLI.isFMAFasterThanFMulAndFAdd(VT) &&
(!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FMA, VT))) {
if (!TLI.isOperationLegal(ISD::FMAD, VT)) {
// Don't form FMA if we are preferring FMAD.
if (SDValue Fused
= performFaddFmulCombines(ISD::FMA,
TLI.enableAggressiveFMAFusion(VT),
N, TLI, DAG)) {
return Fused;
}
}
// When FP_EXTEND nodes are free on the target, and there is an opportunity
// to combine into FMA, arrange such nodes accordingly.
if (TLI.isFPExtFree(VT)) {
// fold (fadd (fpext (fmul x, y)), z) -> (fma (fpext x), (fpext y), z)
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FMUL)
return DAG.getNode(ISD::FMA, SDLoc(N), VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N00.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N00.getOperand(1)), N1);
}
// fold (fadd x, (fpext (fmul y, z)), z) -> (fma (fpext y), (fpext z), x)
// Note: Commutes FADD operands.
if (N1.getOpcode() == ISD::FP_EXTEND) {
SDValue N10 = N1.getOperand(0);
if (N10.getOpcode() == ISD::FMUL)
return DAG.getNode(ISD::FMA, SDLoc(N), VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N10.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N10.getOperand(1)), N0);
}
}
SDValue Fused = visitFADDForFMACombine(N);
if (Fused) {
AddToWorklist(Fused.getNode());
return Fused;
}
return SDValue();
@ -7436,96 +7719,11 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) {
}
}
if (LegalOperations && TLI.isOperationLegal(ISD::FMAD, VT)) {
// Assume if there is an fmad instruction that it should be aggressively
// used.
if (SDValue Fused = performFsubFmulCombines(ISD::FMAD, true, N, TLI, DAG))
return Fused;
}
// FSUB -> FMA combines:
if ((Options.AllowFPOpFusion == FPOpFusion::Fast || Options.UnsafeFPMath) &&
TLI.isFMAFasterThanFMulAndFAdd(VT) &&
(!LegalOperations || TLI.isOperationLegalOrCustom(ISD::FMA, VT))) {
if (!TLI.isOperationLegal(ISD::FMAD, VT)) {
// Don't form FMA if we are preferring FMAD.
if (SDValue Fused
= performFsubFmulCombines(ISD::FMA,
TLI.enableAggressiveFMAFusion(VT),
N, TLI, DAG)) {
return Fused;
}
}
// When FP_EXTEND nodes are free on the target, and there is an opportunity
// to combine into FMA, arrange such nodes accordingly.
if (TLI.isFPExtFree(VT)) {
// fold (fsub (fpext (fmul x, y)), z)
// -> (fma (fpext x), (fpext y), (fneg z))
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FMUL)
return DAG.getNode(ISD::FMA, SDLoc(N), VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N00.getOperand(0)),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N00.getOperand(1)),
DAG.getNode(ISD::FNEG, SDLoc(N), VT, N1));
}
// fold (fsub x, (fpext (fmul y, z)))
// -> (fma (fneg (fpext y)), (fpext z), x)
// Note: Commutes FSUB operands.
if (N1.getOpcode() == ISD::FP_EXTEND) {
SDValue N10 = N1.getOperand(0);
if (N10.getOpcode() == ISD::FMUL)
return DAG.getNode(ISD::FMA, SDLoc(N), VT,
DAG.getNode(ISD::FNEG, SDLoc(N), VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N),
VT, N10.getOperand(0))),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N10.getOperand(1)),
N0);
}
// fold (fsub (fpext (fneg (fmul, x, y))), z)
// -> (fma (fneg (fpext x)), (fpext y), (fneg z))
if (N0.getOpcode() == ISD::FP_EXTEND) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FNEG) {
SDValue N000 = N00.getOperand(0);
if (N000.getOpcode() == ISD::FMUL) {
return DAG.getNode(ISD::FMA, dl, VT,
DAG.getNode(ISD::FNEG, dl, VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N),
VT, N000.getOperand(0))),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N000.getOperand(1)),
DAG.getNode(ISD::FNEG, dl, VT, N1));
}
}
}
// fold (fsub (fneg (fpext (fmul, x, y))), z)
// -> (fma (fneg (fpext x)), (fpext y), (fneg z))
if (N0.getOpcode() == ISD::FNEG) {
SDValue N00 = N0.getOperand(0);
if (N00.getOpcode() == ISD::FP_EXTEND) {
SDValue N000 = N00.getOperand(0);
if (N000.getOpcode() == ISD::FMUL) {
return DAG.getNode(ISD::FMA, dl, VT,
DAG.getNode(ISD::FNEG, dl, VT,
DAG.getNode(ISD::FP_EXTEND, SDLoc(N),
VT, N000.getOperand(0))),
DAG.getNode(ISD::FP_EXTEND, SDLoc(N), VT,
N000.getOperand(1)),
DAG.getNode(ISD::FNEG, dl, VT, N1));
}
}
}
}
SDValue Fused = visitFSUBForFMACombine(N);
if (Fused) {
AddToWorklist(Fused.getNode());
return Fused;
}
return SDValue();

View File

@ -3,11 +3,11 @@
define double @test_FMADD_ASSOC1(double %A, double %B, double %C,
double %D, double %E) {
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fadd double %H, %E ; <double> [#uses=1]
ret double %I
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fadd double %H, %E ; <double> [#uses=1]
ret double %I
; CHECK-LABEL: test_FMADD_ASSOC1:
; CHECK: fmadd
; CHECK-NEXT: fmadd
@ -22,11 +22,11 @@ define double @test_FMADD_ASSOC1(double %A, double %B, double %C,
define double @test_FMADD_ASSOC2(double %A, double %B, double %C,
double %D, double %E) {
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fadd double %E, %H ; <double> [#uses=1]
ret double %I
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fadd double %E, %H ; <double> [#uses=1]
ret double %I
; CHECK-LABEL: test_FMADD_ASSOC2:
; CHECK: fmadd
; CHECK-NEXT: fmadd
@ -41,11 +41,11 @@ define double @test_FMADD_ASSOC2(double %A, double %B, double %C,
define double @test_FMSUB_ASSOC1(double %A, double %B, double %C,
double %D, double %E) {
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fsub double %H, %E ; <double> [#uses=1]
ret double %I
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fsub double %H, %E ; <double> [#uses=1]
ret double %I
; CHECK-LABEL: test_FMSUB_ASSOC1:
; CHECK: fmsub
; CHECK-NEXT: fmadd
@ -60,11 +60,11 @@ define double @test_FMSUB_ASSOC1(double %A, double %B, double %C,
define double @test_FMSUB_ASSOC2(double %A, double %B, double %C,
double %D, double %E) {
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fsub double %E, %H ; <double> [#uses=1]
ret double %I
%F = fmul double %A, %B ; <double> [#uses=1]
%G = fmul double %C, %D ; <double> [#uses=1]
%H = fadd double %F, %G ; <double> [#uses=1]
%I = fsub double %E, %H ; <double> [#uses=1]
ret double %I
; CHECK-LABEL: test_FMSUB_ASSOC2:
; CHECK: fnmsub
; CHECK-NEXT: fnmsub
@ -77,3 +77,159 @@ define double @test_FMSUB_ASSOC2(double %A, double %B, double %C,
; CHECK-VSX-NEXT: blr
}
define double @test_FMADD_ASSOC_EXT1(float %A, float %B, double %C,
double %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fpext float %F to double ; <double> [#uses=1]
%H = fmul double %C, %D ; <double> [#uses=1]
%I = fadd double %H, %G ; <double> [#uses=1]
%J = fadd double %I, %E ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMADD_ASSOC_EXT1:
; CHECK: fmadd
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMADD_ASSOC_EXT1:
; CHECK-VSX: xsmaddmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: blr
}
define double @test_FMADD_ASSOC_EXT2(float %A, float %B, float %C,
float %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fmul float %C, %D ; <float> [#uses=1]
%H = fadd float %F, %G ; <float> [#uses=1]
%I = fpext float %H to double ; <double> [#uses=1]
%J = fadd double %I, %E ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMADD_ASSOC_EXT2:
; CHECK: fmadd
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMADD_ASSOC_EXT2:
; CHECK-VSX: xsmaddmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: fmr
; CHECK-VSX-NEXT: blr
}
define double @test_FMADD_ASSOC_EXT3(float %A, float %B, double %C,
double %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fpext float %F to double ; <double> [#uses=1]
%H = fmul double %C, %D ; <double> [#uses=1]
%I = fadd double %H, %G ; <double> [#uses=1]
%J = fadd double %E, %I ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMADD_ASSOC_EXT3:
; CHECK: fmadd
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMADD_ASSOC_EXT3:
; CHECK-VSX: xsmaddmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: blr
}
define double @test_FMADD_ASSOC_EXT4(float %A, float %B, float %C,
float %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fmul float %C, %D ; <float> [#uses=1]
%H = fadd float %F, %G ; <float> [#uses=1]
%I = fpext float %H to double ; <double> [#uses=1]
%J = fadd double %E, %I ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMADD_ASSOC_EXT4:
; CHECK: fmadd
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMADD_ASSOC_EXT4:
; CHECK-VSX: xsmaddmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: fmr
; CHECK-VSX-NEXT: blr
}
define double @test_FMSUB_ASSOC_EXT1(float %A, float %B, double %C,
double %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fpext float %F to double ; <double> [#uses=1]
%H = fmul double %C, %D ; <double> [#uses=1]
%I = fadd double %H, %G ; <double> [#uses=1]
%J = fsub double %I, %E ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMSUB_ASSOC_EXT1:
; CHECK: fmsub
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_ASSOC_EXT1:
; CHECK-VSX: xsmsubmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: blr
}
define double @test_FMSUB_ASSOC_EXT2(float %A, float %B, float %C,
float %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fmul float %C, %D ; <float> [#uses=1]
%H = fadd float %F, %G ; <float> [#uses=1]
%I = fpext float %H to double ; <double> [#uses=1]
%J = fsub double %I, %E ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMSUB_ASSOC_EXT2:
; CHECK: fmsub
; CHECK-NEXT: fmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_ASSOC_EXT2:
; CHECK-VSX: xsmsubmdp
; CHECK-VSX-NEXT: xsmaddadp
; CHECK-VSX-NEXT: fmr
; CHECK-VSX-NEXT: blr
}
define double @test_FMSUB_ASSOC_EXT3(float %A, float %B, double %C,
double %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fpext float %F to double ; <double> [#uses=1]
%H = fmul double %C, %D ; <double> [#uses=1]
%I = fadd double %H, %G ; <double> [#uses=1]
%J = fsub double %E, %I ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMSUB_ASSOC_EXT3:
; CHECK: fnmsub
; CHECK-NEXT: fnmsub
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_ASSOC_EXT3:
; CHECK-VSX: xsnmsubmdp
; CHECK-VSX-NEXT: xsnmsubadp
; CHECK-VSX-NEXT: fmr
; CHECK-VSX-NEXT: blr
}
define double @test_FMSUB_ASSOC_EXT4(float %A, float %B, float %C,
float %D, double %E) {
%F = fmul float %A, %B ; <float> [#uses=1]
%G = fmul float %C, %D ; <float> [#uses=1]
%H = fadd float %F, %G ; <float> [#uses=1]
%I = fpext float %H to double ; <double> [#uses=1]
%J = fsub double %E, %I ; <double> [#uses=1]
ret double %J
; CHECK-LABEL: test_FMSUB_ASSOC_EXT4:
; CHECK: fnmsub
; CHECK-NEXT: fnmsub
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_ASSOC_EXT4:
; CHECK-VSX: xsnmsubmdp
; CHECK-VSX-NEXT: xsnmsubadp
; CHECK-VSX-NEXT: fmr
; CHECK-VSX-NEXT: blr
}

View File

@ -60,34 +60,34 @@ define double @test_FMSUB_EXT2(float %A, float %B, double %C) {
define double @test_FMSUB_EXT3(float %A, float %B, double %C) {
%D = fmul float %A, %B ; <float> [#uses=1]
%E = fsub float -0.000000e+00, %D ; <float> [#uses=1]
%E = fsub float -0.000000e+00, %D ; <float> [#uses=1]
%F = fpext float %E to double ; <double> [#uses=1]
%G = fsub double %F, %C ; <double> [#uses=1]
ret double %G
; CHECK-LABEL: test_FMSUB_EXT3:
; CHECK: fneg
; CHECK-NEXT: fmsub
; CHECK: fnmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_EXT3:
; CHECK-VSX: xsnegdp
; CHECK-VSX-NEXT: xsmsubmdp
; CHECK-VSX: xsnmaddmdp
; CHECK-VSX-NEXT: blr
}
define double @test_FMSUB_EXT4(float %A, float %B, double %C) {
%D = fmul float %A, %B ; <float> [#uses=1]
%E = fpext float %D to double ; <double> [#uses=1]
%F = fsub double -0.000000e+00, %E ; <double> [#uses=1]
%F = fsub double -0.000000e+00, %E ; <double> [#uses=1]
%G = fsub double %F, %C ; <double> [#uses=1]
ret double %G
; CHECK-LABEL: test_FMSUB_EXT4:
; CHECK: fneg
; CHECK-NEXT: fmsub
; CHECK: fnmadd
; CHECK-NEXT: blr
; CHECK-VSX-LABEL: test_FMSUB_EXT4:
; CHECK-VSX: xsnegdp
; CHECK-VSX-NEXT: xsmsubmdp
; CHECK-VSX: xsnmaddmdp
; CHECK-VSX-NEXT: blr
}
}