Added a TLI hook to signal that the target does not have or does not care about
floating point exceptions, added use of flag to fold potentially exception
raising floating point math in selection DAG. No functionality change, as
targets have to explicitly ask for this behavior and none does today.
llvm-svn: 215222
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 1cfd863..8163041 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3402,6 +3402,7 @@
}
// Constant fold FP operations.
+ bool HasFPExceptions = TLI->hasFloatingPointExceptions();
ConstantFPSDNode *N1CFP = dyn_cast<ConstantFPSDNode>(N1.getNode());
ConstantFPSDNode *N2CFP = dyn_cast<ConstantFPSDNode>(N2.getNode());
if (N1CFP) {
@@ -3415,28 +3416,32 @@
switch (Opcode) {
case ISD::FADD:
s = V1.add(V2, APFloat::rmNearestTiesToEven);
- if (s != APFloat::opInvalidOp)
+ if (!HasFPExceptions || s != APFloat::opInvalidOp)
return getConstantFP(V1, VT);
break;
case ISD::FSUB:
s = V1.subtract(V2, APFloat::rmNearestTiesToEven);
- if (s!=APFloat::opInvalidOp)
+ if (!HasFPExceptions || s!=APFloat::opInvalidOp)
return getConstantFP(V1, VT);
break;
case ISD::FMUL:
s = V1.multiply(V2, APFloat::rmNearestTiesToEven);
- if (s!=APFloat::opInvalidOp)
+ if (!HasFPExceptions || s!=APFloat::opInvalidOp)
return getConstantFP(V1, VT);
break;
case ISD::FDIV:
s = V1.divide(V2, APFloat::rmNearestTiesToEven);
- if (s!=APFloat::opInvalidOp && s!=APFloat::opDivByZero)
+ if (!HasFPExceptions || (s!=APFloat::opInvalidOp &&
+ s!=APFloat::opDivByZero)) {
return getConstantFP(V1, VT);
+ }
break;
case ISD::FREM :
s = V1.mod(V2, APFloat::rmNearestTiesToEven);
- if (s!=APFloat::opInvalidOp && s!=APFloat::opDivByZero)
+ if (!HasFPExceptions || (s!=APFloat::opInvalidOp &&
+ s!=APFloat::opDivByZero)) {
return getConstantFP(V1, VT);
+ }
break;
case ISD::FCOPYSIGN:
V1.copySign(V2);