[Reassociate] Don't reassociate when mixing regular and fast-math FP
instructions. Inlining might cause such cases and it's not valid to
reassociate floating-point instructions without the unsafe algebra flag.
Patch by Mehdi Amini <mehdi_amini@apple.com>!
llvm-svn: 221462
diff --git a/llvm/lib/Transforms/Scalar/Reassociate.cpp b/llvm/lib/Transforms/Scalar/Reassociate.cpp
index 0d5ad73..02cf708 100644
--- a/llvm/lib/Transforms/Scalar/Reassociate.cpp
+++ b/llvm/lib/Transforms/Scalar/Reassociate.cpp
@@ -237,7 +237,9 @@
/// opcode and if it only has one use.
static BinaryOperator *isReassociableOp(Value *V, unsigned Opcode) {
if (V->hasOneUse() && isa<Instruction>(V) &&
- cast<Instruction>(V)->getOpcode() == Opcode)
+ cast<Instruction>(V)->getOpcode() == Opcode &&
+ (!isa<FPMathOperator>(V) ||
+ cast<Instruction>(V)->hasUnsafeAlgebra()))
return cast<BinaryOperator>(V);
return nullptr;
}
@@ -246,7 +248,9 @@
unsigned Opcode2) {
if (V->hasOneUse() && isa<Instruction>(V) &&
(cast<Instruction>(V)->getOpcode() == Opcode1 ||
- cast<Instruction>(V)->getOpcode() == Opcode2))
+ cast<Instruction>(V)->getOpcode() == Opcode2) &&
+ (!isa<FPMathOperator>(V) ||
+ cast<Instruction>(V)->hasUnsafeAlgebra()))
return cast<BinaryOperator>(V);
return nullptr;
}
@@ -662,7 +666,9 @@
// expression. This means that it can safely be modified. See if we
// can usefully morph it into an expression of the right kind.
assert((!isa<Instruction>(Op) ||
- cast<Instruction>(Op)->getOpcode() != Opcode) &&
+ cast<Instruction>(Op)->getOpcode() != Opcode
+ || (isa<FPMathOperator>(Op) &&
+ !cast<Instruction>(Op)->hasUnsafeAlgebra())) &&
"Should have been handled above!");
assert(Op->hasOneUse() && "Has uses outside the expression tree!");