diff options
| author | Dan Gohman <gohman@apple.com> | 2009-06-04 17:12:12 +0000 |
|---|---|---|
| committer | Dan Gohman <gohman@apple.com> | 2009-06-04 17:12:12 +0000 |
| commit | 77b81fe487de709d41dfcc97bbb2941ae1bb80af (patch) | |
| tree | 9730d59d8f6ae8de964c38fd56884553c77db692 /lib/CodeGen/SelectionDAG/DAGCombiner.cpp | |
| parent | 68f32cbb1f9e62d5e6047b048c0d7d217b8717e1 (diff) | |
Don't do the X * 0.0 -> 0.0 transformation in instcombine, because
instcombine doesn't know when it's safe. To partially compensate
for this, introduce new code to do this transformation in
dagcombine, which can use UnsafeFPMath.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72872 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 3 |
1 files changed, 3 insertions, 0 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 4c1710dd81..5d1b2a3ea2 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -4019,6 +4019,9 @@ SDValue DAGCombiner::visitFMUL(SDNode *N) { // fold (fmul A, 0) -> 0 if (UnsafeFPMath && N1CFP && N1CFP->getValueAPF().isZero()) return N1; + // fold (fmul A, 0) -> 0, vector edition. + if (UnsafeFPMath && ISD::isBuildVectorAllZeros(N1.getNode())) + return N1; // fold (fmul X, 2.0) -> (fadd X, X) if (N1CFP && N1CFP->isExactlyValue(+2.0)) return DAG.getNode(ISD::FADD, N->getDebugLoc(), VT, N0, N0); |