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| author | Sanjay Patel <spatel@rotateright.com> | 2019-02-09 15:59:02 +0000 |
|---|---|---|
| committer | Sanjay Patel <spatel@rotateright.com> | 2019-02-09 15:59:02 +0000 |
| commit | 887ac1b38ce273cd70dda4ee184d974f3094da52 (patch) | |
| tree | 2efc676a7ace635eb0e8de65c7fea2295bfdc0f2 /llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp | |
| parent | 6404af86466cd2a2db84779769e070b5c7784725 (diff) | |
| download | bcm5719-llvm-887ac1b38ce273cd70dda4ee184d974f3094da52.tar.gz bcm5719-llvm-887ac1b38ce273cd70dda4ee184d974f3094da52.zip | |
[TargetLowering] avoid miscompile in setcc transform (PR40657)
llvm-svn: 353615
Diffstat (limited to 'llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp')
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp | 4 |
1 files changed, 3 insertions, 1 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp index 484dbffefbb..b933f032409 100644 --- a/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/TargetLowering.cpp @@ -3074,7 +3074,9 @@ SDValue TargetLowering::SimplifySetCC(EVT VT, SDValue N0, SDValue N1, return DAG.getSetCC(dl, VT, N0.getOperand(0), DAG.getConstant(0, dl, N0.getValueType()), Cond); - if (N0.getNode()->hasOneUse()) { + // The shift is not valid if this is a bool (i1). + // TODO: This transform needs evidence to justify its existence. + if (N0.getNode()->hasOneUse() && OpVT.getScalarSizeInBits() != 1) { assert(N0.getOpcode() == ISD::SUB && "Unexpected operation!"); auto &DL = DAG.getDataLayout(); // (Z-X) == X --> Z == X<<1 |
