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| author | Owen Anderson <resistor@mac.com> | 2012-04-02 22:10:29 +0000 |
|---|---|---|
| committer | Owen Anderson <resistor@mac.com> | 2012-04-02 22:10:29 +0000 |
| commit | 29f60f359b59032108cdabcde91217b6784c4e13 (patch) | |
| tree | f0cf6d663860ff858955be8e0208910675fd94c8 /lib/CodeGen/SelectionDAG/DAGCombiner.cpp | |
| parent | be9fe49b179a89a659fe786d64b176d2b360bb4a (diff) | |
| download | external_llvm-29f60f359b59032108cdabcde91217b6784c4e13.tar.gz external_llvm-29f60f359b59032108cdabcde91217b6784c4e13.tar.bz2 external_llvm-29f60f359b59032108cdabcde91217b6784c4e13.zip | |
Add predicates for checking whether targets have free FNEG and FABS operations, and prevent the DAGCombiner from turning them into bitwise operations if they do.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153901 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib/CodeGen/SelectionDAG/DAGCombiner.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/DAGCombiner.cpp | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp index 08946070b4..a71cf82cd5 100644 --- a/lib/CodeGen/SelectionDAG/DAGCombiner.cpp +++ b/lib/CodeGen/SelectionDAG/DAGCombiner.cpp @@ -5342,7 +5342,8 @@ SDValue DAGCombiner::visitBITCAST(SDNode *N) { // fold (bitconvert (fneg x)) -> (xor (bitconvert x), signbit) // fold (bitconvert (fabs x)) -> (and (bitconvert x), (not signbit)) // This often reduces constant pool loads. - if ((N0.getOpcode() == ISD::FNEG || N0.getOpcode() == ISD::FABS) && + if (((N0.getOpcode() == ISD::FNEG && !TLI.isFNegFree(VT)) || + (N0.getOpcode() == ISD::FABS && !TLI.isFAbsFree(VT))) && N0.getNode()->hasOneUse() && VT.isInteger() && !VT.isVector()) { SDValue NewConv = DAG.getNode(ISD::BITCAST, N0.getDebugLoc(), VT, N0.getOperand(0)); @@ -5993,7 +5994,7 @@ SDValue DAGCombiner::visitFNEG(SDNode *N) { // Transform fneg(bitconvert(x)) -> bitconvert(x^sign) to avoid loading // constant pool values. - if (N0.getOpcode() == ISD::BITCAST && + if (!TLI.isFNegFree(VT) && N0.getOpcode() == ISD::BITCAST && !VT.isVector() && N0.getNode()->hasOneUse() && N0.getOperand(0).getValueType().isInteger()) { @@ -6029,7 +6030,8 @@ SDValue DAGCombiner::visitFABS(SDNode *N) { // Transform fabs(bitconvert(x)) -> bitconvert(x&~sign) to avoid loading // constant pool values. - if (N0.getOpcode() == ISD::BITCAST && N0.getNode()->hasOneUse() && + if (!TLI.isFAbsFree(VT) && + N0.getOpcode() == ISD::BITCAST && N0.getNode()->hasOneUse() && N0.getOperand(0).getValueType().isInteger() && !N0.getOperand(0).getValueType().isVector()) { SDValue Int = N0.getOperand(0); |