SDValue visitMLOAD(SDNode *N);
SDValue visitMSTORE(SDNode *N);
- SDValue visitFADDForFMACombine(SDNode *N);
- SDValue visitFSUBForFMACombine(SDNode *N);
-
SDValue XformToShuffleWithZero(SDNode *N);
SDValue ReassociateOps(unsigned Opc, SDLoc DL, SDValue LHS, SDValue RHS);
return DAG.getNode(ISD::BUILD_VECTOR, SDLoc(BV), VT, Ops);
}
-/// Try to perform FMA combining on a given FADD node.
-SDValue DAGCombiner::visitFADDForFMACombine(SDNode *N) {
+// 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) {
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(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), VT,
N0.getOperand(0), N0.getOperand(1), N1);
}
// Note: Commutes FADD operands.
if (N1.getOpcode() == ISD::FMUL &&
(Aggressive || N1->hasOneUse())) {
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), 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 (UnsafeFPMath && Aggressive) {
+ if (Aggressive) {
// fold (fadd (fma x, y, (fmul u, v)), z) -> (fma x, y (fma u, v, z))
- if (N0.getOpcode() == PreferredFusedOpcode &&
+ if (N0.getOpcode() == ISD::FMA &&
N0.getOperand(2).getOpcode() == ISD::FMUL) {
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), VT,
N0.getOperand(0), N0.getOperand(1),
- DAG.getNode(PreferredFusedOpcode, SL, VT,
+ DAG.getNode(FusedOpcode, SDLoc(N), 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() == PreferredFusedOpcode &&
+ if (N1->getOpcode() == ISD::FMA &&
N1.getOperand(2).getOpcode() == ISD::FMUL) {
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), VT,
N1.getOperand(0), N1.getOperand(1),
- DAG.getNode(PreferredFusedOpcode, SL, VT,
+ DAG.getNode(FusedOpcode, SDLoc(N), 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();
}
-/// Try to perform FMA combining on a given FSUB node.
-SDValue DAGCombiner::visitFSUBForFMACombine(SDNode *N) {
+static SDValue performFsubFmulCombines(unsigned FusedOpcode,
+ bool Aggressive,
+ SDNode *N,
+ const TargetLowering &TLI,
+ SelectionDAG &DAG) {
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);
+ SDLoc SL(N);
// fold (fsub (fmul x, y), z) -> (fma x, y, (fneg z))
if (N0.getOpcode() == ISD::FMUL &&
(Aggressive || N0->hasOneUse())) {
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SL, VT,
N0.getOperand(0), N0.getOperand(1),
DAG.getNode(ISD::FNEG, SL, VT, N1));
}
// Note: Commutes FSUB operands.
if (N1.getOpcode() == ISD::FMUL &&
(Aggressive || N1->hasOneUse()))
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SL, VT,
DAG.getNode(ISD::FNEG, SL, VT,
N1.getOperand(0)),
N1.getOperand(1), N0);
(Aggressive || (N0->hasOneUse() && N0.getOperand(0).hasOneUse()))) {
SDValue N00 = N0.getOperand(0).getOperand(0);
SDValue N01 = N0.getOperand(0).getOperand(1);
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, 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 (UnsafeFPMath && Aggressive) {
+ if (Aggressive) {
// fold (fsub (fma x, y, (fmul u, v)), z)
// -> (fma x, y (fma u, v, (fneg z)))
- if (N0.getOpcode() == PreferredFusedOpcode &&
+ if (N0.getOpcode() == FusedOpcode &&
N0.getOperand(2).getOpcode() == ISD::FMUL) {
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), VT,
N0.getOperand(0), N0.getOperand(1),
- DAG.getNode(PreferredFusedOpcode, SL, VT,
+ DAG.getNode(FusedOpcode, SDLoc(N), VT,
N0.getOperand(2).getOperand(0),
N0.getOperand(2).getOperand(1),
- DAG.getNode(ISD::FNEG, SL, VT,
+ DAG.getNode(ISD::FNEG, SDLoc(N), VT,
N1)));
}
// fold (fsub x, (fma y, z, (fmul u, v)))
// -> (fma (fneg y), z, (fma (fneg u), v, x))
- if (N1.getOpcode() == PreferredFusedOpcode &&
+ if (N1.getOpcode() == FusedOpcode &&
N1.getOperand(2).getOpcode() == ISD::FMUL) {
SDValue N20 = N1.getOperand(2).getOperand(0);
SDValue N21 = N1.getOperand(2).getOperand(1);
- return DAG.getNode(PreferredFusedOpcode, SL, VT,
- DAG.getNode(ISD::FNEG, SL, VT,
+ return DAG.getNode(FusedOpcode, SDLoc(N), VT,
+ DAG.getNode(ISD::FNEG, SDLoc(N), VT,
N1.getOperand(0)),
N1.getOperand(1),
- DAG.getNode(PreferredFusedOpcode, SL, VT,
- DAG.getNode(ISD::FNEG, SL, VT, N20),
+ DAG.getNode(FusedOpcode, SDLoc(N), VT,
+ DAG.getNode(ISD::FNEG, SDLoc(N), 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();
}
} // 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:
- SDValue Fused = visitFADDForFMACombine(N);
- if (Fused) {
- AddToWorklist(Fused.getNode());
- return Fused;
+ 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);
+ }
+ }
}
return SDValue();
}
}
+ 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:
- SDValue Fused = visitFSUBForFMACombine(N);
- if (Fused) {
- AddToWorklist(Fused.getNode());
- return Fused;
+ 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));
+ }
+ }
+ }
+ }
}
return SDValue();