DAGCombine: always constant fold FMA when target disable FP exceptions

Summary: When trying to constant fold an FMA in the DAG, getNode()
fails to fold the FMA if an operand is not finite. In this case this
patch allows the constant folding if !TLI->hasFloatingPointExceptions()

Reviewers: resistor

Reviewed By: resistor

Subscribers: hfinkel, llvm-commits

Differential Revision: http://reviews.llvm.org/D6912

From: Mehdi Amini <mehdi.amini@apple.com>

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@226901 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
index 24e9df3c71dc488bc17ce8e290687a43a98cdf2e..c354155b0358dce8af50f425b4ea845e2336a783 100644 (file)
--- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -3620,7 +3620,7 @@ SDValue SelectionDAG::getNode(unsigned Opcode, SDLoc DL, EVT VT,
       const APFloat &V3 = N3CFP->getValueAPF();
       APFloat::opStatus s =
         V1.fusedMultiplyAdd(V2, V3, APFloat::rmNearestTiesToEven);
-      if (s != APFloat::opInvalidOp)
+      if (!TLI->hasFloatingPointExceptions() || s != APFloat::opInvalidOp)
         return getConstantFP(V1, VT);
     }
     break;