diff options
| -rw-r--r-- | llvm/include/llvm/CodeGen/SelectionDAG.h | 7 | ||||
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 12 | ||||
| -rw-r--r-- | llvm/lib/Target/X86/X86ISelLowering.cpp | 16 |
3 files changed, 26 insertions, 9 deletions
diff --git a/llvm/include/llvm/CodeGen/SelectionDAG.h b/llvm/include/llvm/CodeGen/SelectionDAG.h index 323c58a6568..3334c12b775 100644 --- a/llvm/include/llvm/CodeGen/SelectionDAG.h +++ b/llvm/include/llvm/CodeGen/SelectionDAG.h @@ -1487,8 +1487,11 @@ public: /// Test whether the given SDValue is known to never be NaN. bool isKnownNeverNaN(SDValue Op) const; - /// Test whether the given SDValue is known to never be positive or negative - /// zero. + /// Test whether the given floating point SDValue is known to never be + /// positive or negative zero. + bool isKnownNeverZeroFloat(SDValue Op) const; + + /// Test whether the given SDValue is known to contain non-zero value(s). bool isKnownNeverZero(SDValue Op) const; /// Test whether two SDValues are known to compare equal. This diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 20c0c35332e..1abc8c99efd 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -3611,10 +3611,20 @@ bool SelectionDAG::isKnownNeverNaN(SDValue Op) const { return false; } -bool SelectionDAG::isKnownNeverZero(SDValue Op) const { +bool SelectionDAG::isKnownNeverZeroFloat(SDValue Op) const { + assert(Op.getValueType().isFloatingPoint() && + "Floating point type expected"); + // If the value is a constant, we can obviously see if it is a zero or not. + // TODO: Add BuildVector support. if (const ConstantFPSDNode *C = dyn_cast<ConstantFPSDNode>(Op)) return !C->isZero(); + return false; +} + +bool SelectionDAG::isKnownNeverZero(SDValue Op) const { + assert(!Op.getValueType().isFloatingPoint() && + "Floating point types unsupported - use isKnownNeverZeroFloat"); // TODO: Recognize more cases here. switch (Op.getOpcode()) { diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp index d7d4a1a8344..9f087a29894 100644 --- a/llvm/lib/Target/X86/X86ISelLowering.cpp +++ b/llvm/lib/Target/X86/X86ISelLowering.cpp @@ -32639,7 +32639,8 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // and negative zero incorrectly. if (!DAG.isKnownNeverNaN(LHS) || !DAG.isKnownNeverNaN(RHS)) { if (!DAG.getTarget().Options.UnsafeFPMath && - !(DAG.isKnownNeverZero(LHS) || DAG.isKnownNeverZero(RHS))) + !(DAG.isKnownNeverZeroFloat(LHS) || + DAG.isKnownNeverZeroFloat(RHS))) break; std::swap(LHS, RHS); } @@ -32649,7 +32650,7 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // Converting this to a min would handle comparisons between positive // and negative zero incorrectly. if (!DAG.getTarget().Options.UnsafeFPMath && - !DAG.isKnownNeverZero(LHS) && !DAG.isKnownNeverZero(RHS)) + !DAG.isKnownNeverZeroFloat(LHS) && !DAG.isKnownNeverZeroFloat(RHS)) break; Opcode = X86ISD::FMIN; break; @@ -32668,7 +32669,7 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // Converting this to a max would handle comparisons between positive // and negative zero incorrectly. if (!DAG.getTarget().Options.UnsafeFPMath && - !DAG.isKnownNeverZero(LHS) && !DAG.isKnownNeverZero(RHS)) + !DAG.isKnownNeverZeroFloat(LHS) && !DAG.isKnownNeverZeroFloat(RHS)) break; Opcode = X86ISD::FMAX; break; @@ -32678,7 +32679,8 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // and negative zero incorrectly. if (!DAG.isKnownNeverNaN(LHS) || !DAG.isKnownNeverNaN(RHS)) { if (!DAG.getTarget().Options.UnsafeFPMath && - !(DAG.isKnownNeverZero(LHS) || DAG.isKnownNeverZero(RHS))) + !(DAG.isKnownNeverZeroFloat(LHS) || + DAG.isKnownNeverZeroFloat(RHS))) break; std::swap(LHS, RHS); } @@ -32705,7 +32707,8 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // and negative zero incorrectly, and swapping the operands would // cause it to handle NaNs incorrectly. if (!DAG.getTarget().Options.UnsafeFPMath && - !(DAG.isKnownNeverZero(LHS) || DAG.isKnownNeverZero(RHS))) { + !(DAG.isKnownNeverZeroFloat(LHS) || + DAG.isKnownNeverZeroFloat(RHS))) { if (!DAG.isKnownNeverNaN(LHS) || !DAG.isKnownNeverNaN(RHS)) break; std::swap(LHS, RHS); @@ -32741,7 +32744,8 @@ static SDValue combineSelect(SDNode *N, SelectionDAG &DAG, // and negative zero incorrectly, and swapping the operands would // cause it to handle NaNs incorrectly. if (!DAG.getTarget().Options.UnsafeFPMath && - !DAG.isKnownNeverZero(LHS) && !DAG.isKnownNeverZero(RHS)) { + !DAG.isKnownNeverZeroFloat(LHS) && + !DAG.isKnownNeverZeroFloat(RHS)) { if (!DAG.isKnownNeverNaN(LHS) || !DAG.isKnownNeverNaN(RHS)) break; std::swap(LHS, RHS); |
