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-rw-r--r--lib/CodeGen/SelectionDAG/DAGCombiner.cpp135
1 files changed, 91 insertions, 44 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
index d8208a4..80cf0a8 100644
--- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
+++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -180,7 +180,9 @@ namespace {
SDValue visitSRA(SDNode *N);
SDValue visitSRL(SDNode *N);
SDValue visitCTLZ(SDNode *N);
+ SDValue visitCTLZ_ZERO_UNDEF(SDNode *N);
SDValue visitCTTZ(SDNode *N);
+ SDValue visitCTTZ_ZERO_UNDEF(SDNode *N);
SDValue visitCTPOP(SDNode *N);
SDValue visitSELECT(SDNode *N);
SDValue visitSELECT_CC(SDNode *N);
@@ -361,6 +363,7 @@ CommitTargetLoweringOpt(const TargetLowering::TargetLoweringOpt &TLO) {
/// specified expression for the same cost as the expression itself, or 2 if we
/// can compute the negated form more cheaply than the expression itself.
static char isNegatibleForFree(SDValue Op, bool LegalOperations,
+ const TargetOptions *Options,
unsigned Depth = 0) {
// No compile time optimizations on this type.
if (Op.getValueType() == MVT::ppcf128)
@@ -383,34 +386,39 @@ static char isNegatibleForFree(SDValue Op, bool LegalOperations,
return LegalOperations ? 0 : 1;
case ISD::FADD:
// FIXME: determine better conditions for this xform.
- if (!UnsafeFPMath) return 0;
+ if (!Options->UnsafeFPMath) return 0;
// fold (fsub (fadd A, B)) -> (fsub (fneg A), B)
- if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
+ if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Options,
+ Depth + 1))
return V;
// fold (fneg (fadd A, B)) -> (fsub (fneg B), A)
- return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1);
+ return isNegatibleForFree(Op.getOperand(1), LegalOperations, Options,
+ Depth + 1);
case ISD::FSUB:
// We can't turn -(A-B) into B-A when we honor signed zeros.
- if (!UnsafeFPMath) return 0;
+ if (!Options->UnsafeFPMath) return 0;
// fold (fneg (fsub A, B)) -> (fsub B, A)
return 1;
case ISD::FMUL:
case ISD::FDIV:
- if (HonorSignDependentRoundingFPMath()) return 0;
+ if (Options->HonorSignDependentRoundingFPMath()) return 0;
// fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y) or (fmul X, (fneg Y))
- if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
+ if (char V = isNegatibleForFree(Op.getOperand(0), LegalOperations, Options,
+ Depth + 1))
return V;
- return isNegatibleForFree(Op.getOperand(1), LegalOperations, Depth+1);
+ return isNegatibleForFree(Op.getOperand(1), LegalOperations, Options,
+ Depth + 1);
case ISD::FP_EXTEND:
case ISD::FP_ROUND:
case ISD::FSIN:
- return isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1);
+ return isNegatibleForFree(Op.getOperand(0), LegalOperations, Options,
+ Depth + 1);
}
}
@@ -434,10 +442,11 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG,
}
case ISD::FADD:
// FIXME: determine better conditions for this xform.
- assert(UnsafeFPMath);
+ assert(DAG.getTarget().Options.UnsafeFPMath);
// fold (fneg (fadd A, B)) -> (fsub (fneg A), B)
- if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
+ if (isNegatibleForFree(Op.getOperand(0), LegalOperations,
+ &DAG.getTarget().Options, Depth+1))
return DAG.getNode(ISD::FSUB, Op.getDebugLoc(), Op.getValueType(),
GetNegatedExpression(Op.getOperand(0), DAG,
LegalOperations, Depth+1),
@@ -449,7 +458,7 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG,
Op.getOperand(0));
case ISD::FSUB:
// We can't turn -(A-B) into B-A when we honor signed zeros.
- assert(UnsafeFPMath);
+ assert(DAG.getTarget().Options.UnsafeFPMath);
// fold (fneg (fsub 0, B)) -> B
if (ConstantFPSDNode *N0CFP = dyn_cast<ConstantFPSDNode>(Op.getOperand(0)))
@@ -462,10 +471,11 @@ static SDValue GetNegatedExpression(SDValue Op, SelectionDAG &DAG,
case ISD::FMUL:
case ISD::FDIV:
- assert(!HonorSignDependentRoundingFPMath());
+ assert(!DAG.getTarget().Options.HonorSignDependentRoundingFPMath());
// fold (fneg (fmul X, Y)) -> (fmul (fneg X), Y)
- if (isNegatibleForFree(Op.getOperand(0), LegalOperations, Depth+1))
+ if (isNegatibleForFree(Op.getOperand(0), LegalOperations,
+ &DAG.getTarget().Options, Depth+1))
return DAG.getNode(Op.getOpcode(), Op.getDebugLoc(), Op.getValueType(),
GetNegatedExpression(Op.getOperand(0), DAG,
LegalOperations, Depth+1),
@@ -1070,7 +1080,9 @@ SDValue DAGCombiner::visit(SDNode *N) {
case ISD::SRA: return visitSRA(N);
case ISD::SRL: return visitSRL(N);
case ISD::CTLZ: return visitCTLZ(N);
+ case ISD::CTLZ_ZERO_UNDEF: return visitCTLZ_ZERO_UNDEF(N);
case ISD::CTTZ: return visitCTTZ(N);
+ case ISD::CTTZ_ZERO_UNDEF: return visitCTTZ_ZERO_UNDEF(N);
case ISD::CTPOP: return visitCTPOP(N);
case ISD::SELECT: return visitSELECT(N);
case ISD::SELECT_CC: return visitSELECT_CC(N);
@@ -1769,7 +1781,7 @@ SDValue DAGCombiner::visitSDIV(SDNode *N) {
N0, N1);
}
// fold (sdiv X, pow2) -> simple ops after legalize
- if (N1C && !N1C->isNullValue() && !TLI.isIntDivCheap() &&
+ if (N1C && !N1C->isNullValue() &&
(N1C->getAPIntValue().isPowerOf2() ||
(-N1C->getAPIntValue()).isPowerOf2())) {
// If dividing by powers of two is cheap, then don't perform the following
@@ -3709,6 +3721,16 @@ SDValue DAGCombiner::visitCTLZ(SDNode *N) {
return SDValue();
}
+SDValue DAGCombiner::visitCTLZ_ZERO_UNDEF(SDNode *N) {
+ SDValue N0 = N->getOperand(0);
+ EVT VT = N->getValueType(0);
+
+ // fold (ctlz_zero_undef c1) -> c2
+ if (isa<ConstantSDNode>(N0))
+ return DAG.getNode(ISD::CTLZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0);
+ return SDValue();
+}
+
SDValue DAGCombiner::visitCTTZ(SDNode *N) {
SDValue N0 = N->getOperand(0);
EVT VT = N->getValueType(0);
@@ -3719,6 +3741,16 @@ SDValue DAGCombiner::visitCTTZ(SDNode *N) {
return SDValue();
}
+SDValue DAGCombiner::visitCTTZ_ZERO_UNDEF(SDNode *N) {
+ SDValue N0 = N->getOperand(0);
+ EVT VT = N->getValueType(0);
+
+ // fold (cttz_zero_undef c1) -> c2
+ if (isa<ConstantSDNode>(N0))
+ return DAG.getNode(ISD::CTTZ_ZERO_UNDEF, N->getDebugLoc(), VT, N0);
+ return SDValue();
+}
+
SDValue DAGCombiner::visitCTPOP(SDNode *N) {
SDValue N0 = N->getOperand(0);
EVT VT = N->getValueType(0);
@@ -5254,20 +5286,22 @@ SDValue DAGCombiner::visitFADD(SDNode *N) {
if (N0CFP && !N1CFP)
return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N1, N0);
// fold (fadd A, 0) -> A
- if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
+ if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
+ N1CFP->getValueAPF().isZero())
return N0;
// fold (fadd A, (fneg B)) -> (fsub A, B)
- if (isNegatibleForFree(N1, LegalOperations) == 2)
+ if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options) == 2)
return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0,
GetNegatedExpression(N1, DAG, LegalOperations));
// fold (fadd (fneg A), B) -> (fsub B, A)
- if (isNegatibleForFree(N0, LegalOperations) == 2)
+ if (isNegatibleForFree(N0, LegalOperations, &DAG.getTarget().Options) == 2)
return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N1,
GetNegatedExpression(N0, DAG, LegalOperations));
// If allowed, fold (fadd (fadd x, c1), c2) -> (fadd x, (fadd c1, c2))
- if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FADD &&
- N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1)))
+ if (DAG.getTarget().Options.UnsafeFPMath && N1CFP &&
+ N0.getOpcode() == ISD::FADD && N0.getNode()->hasOneUse() &&
+ isa<ConstantFPSDNode>(N0.getOperand(1)))
return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0.getOperand(0),
DAG.getNode(ISD::FADD, N->getDebugLoc(), VT,
N0.getOperand(1), N1));
@@ -5292,17 +5326,19 @@ SDValue DAGCombiner::visitFSUB(SDNode *N) {
if (N0CFP && N1CFP && VT != MVT::ppcf128)
return DAG.getNode(ISD::FSUB, N->getDebugLoc(), VT, N0, N1);
// fold (fsub A, 0) -> A
- if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
+ if (DAG.getTarget().Options.UnsafeFPMath &&
+ N1CFP && N1CFP->getValueAPF().isZero())
return N0;
// fold (fsub 0, B) -> -B
- if (UnsafeFPMath && N0CFP && N0CFP->getValueAPF().isZero()) {
- if (isNegatibleForFree(N1, LegalOperations))
+ if (DAG.getTarget().Options.UnsafeFPMath &&
+ N0CFP && N0CFP->getValueAPF().isZero()) {
+ if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options))
return GetNegatedExpression(N1, DAG, LegalOperations);
if (!LegalOperations || TLI.isOperationLegal(ISD::FNEG, VT))
return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N1);
}
// fold (fsub A, (fneg B)) -> (fadd A, B)
- if (isNegatibleForFree(N1, LegalOperations))
+ if (isNegatibleForFree(N1, LegalOperations, &DAG.getTarget().Options))
return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0,
GetNegatedExpression(N1, DAG, LegalOperations));
@@ -5329,10 +5365,12 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) {
if (N0CFP && !N1CFP)
return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N1, N0);
// fold (fmul A, 0) -> 0
- if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero())
+ if (DAG.getTarget().Options.UnsafeFPMath &&
+ N1CFP && N1CFP->getValueAPF().isZero())
return N1;
// fold (fmul A, 0) -> 0, vector edition.
- if (UnsafeFPMath && ISD::isBuildVectorAllZeros(N1.getNode()))
+ if (DAG.getTarget().Options.UnsafeFPMath &&
+ ISD::isBuildVectorAllZeros(N1.getNode()))
return N1;
// fold (fmul X, 2.0) -> (fadd X, X)
if (N1CFP && N1CFP->isExactlyValue(+2.0))
@@ -5343,8 +5381,10 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) {
return DAG.getNode(ISD::FNEG, N->getDebugLoc(), VT, N0);
// fold (fmul (fneg X), (fneg Y)) -> (fmul X, Y)
- if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) {
- if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) {
+ if (char LHSNeg = isNegatibleForFree(N0, LegalOperations,
+ &DAG.getTarget().Options)) {
+ if (char RHSNeg = isNegatibleForFree(N1, LegalOperations,
+ &DAG.getTarget().Options)) {
// Both can be negated for free, check to see if at least one is cheaper
// negated.
if (LHSNeg == 2 || RHSNeg == 2)
@@ -5355,7 +5395,8 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) {
}
// If allowed, fold (fmul (fmul x, c1), c2) -> (fmul x, (fmul c1, c2))
- if (UnsafeFPMath && N1CFP && N0.getOpcode() == ISD::FMUL &&
+ if (DAG.getTarget().Options.UnsafeFPMath &&
+ N1CFP && N0.getOpcode() == ISD::FMUL &&
N0.getNode()->hasOneUse() && isa<ConstantFPSDNode>(N0.getOperand(1)))
return DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT, N0.getOperand(0),
DAG.getNode(ISD::FMUL, N->getDebugLoc(), VT,
@@ -5383,8 +5424,10 @@ SDValue DAGCombiner::visitFDIV(SDNode *N) {
// (fdiv (fneg X), (fneg Y)) -> (fdiv X, Y)
- if (char LHSNeg = isNegatibleForFree(N0, LegalOperations)) {
- if (char RHSNeg = isNegatibleForFree(N1, LegalOperations)) {
+ if (char LHSNeg = isNegatibleForFree(N0, LegalOperations,
+ &DAG.getTarget().Options)) {
+ if (char RHSNeg = isNegatibleForFree(N1, LegalOperations,
+ &DAG.getTarget().Options)) {
// Both can be negated for free, check to see if at least one is cheaper
// negated.
if (LHSNeg == 2 || RHSNeg == 2)
@@ -5637,7 +5680,7 @@ SDValue DAGCombiner::visitFNEG(SDNode *N) {
SDValue N0 = N->getOperand(0);
EVT VT = N->getValueType(0);
- if (isNegatibleForFree(N0, LegalOperations))
+ if (isNegatibleForFree(N0, LegalOperations, &DAG.getTarget().Options))
return GetNegatedExpression(N0, DAG, LegalOperations);
// Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading
@@ -7162,19 +7205,23 @@ SDValue DAGCombiner::visitEXTRACT_SUBVECTOR(SDNode* N) {
if (NVT != SmallVT || NVT.getSizeInBits()*2 != BigVT.getSizeInBits())
return SDValue();
- // Combine:
- // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx)
- // Into:
- // indicies are equal => V1
- // otherwise => (extract_subvec V1, ExtIdx)
- //
- SDValue InsIdx = N->getOperand(1);
- SDValue ExtIdx = V->getOperand(2);
-
- if (InsIdx == ExtIdx)
- return V->getOperand(1);
- return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT,
- V->getOperand(0), N->getOperand(1));
+ // Only handle cases where both indexes are constants with the same type.
+ ConstantSDNode *InsIdx = dyn_cast<ConstantSDNode>(N->getOperand(1));
+ ConstantSDNode *ExtIdx = dyn_cast<ConstantSDNode>(V->getOperand(2));
+
+ if (InsIdx && ExtIdx &&
+ InsIdx->getValueType(0).getSizeInBits() <= 64 &&
+ ExtIdx->getValueType(0).getSizeInBits() <= 64) {
+ // Combine:
+ // (extract_subvec (insert_subvec V1, V2, InsIdx), ExtIdx)
+ // Into:
+ // indices are equal => V1
+ // otherwise => (extract_subvec V1, ExtIdx)
+ if (InsIdx->getZExtValue() == ExtIdx->getZExtValue())
+ return V->getOperand(1);
+ return DAG.getNode(ISD::EXTRACT_SUBVECTOR, N->getDebugLoc(), NVT,
+ V->getOperand(0), N->getOperand(1));
+ }
}
return SDValue();