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author | Tim Northover <tnorthover@apple.com> | 2017-06-20 15:01:38 +0000 |
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committer | Tim Northover <tnorthover@apple.com> | 2017-06-20 15:01:38 +0000 |
commit | 208ddc5bdc554ed7c90d4515a04bb8f720b82213 (patch) | |
tree | 9f082aa9bd97f94712a7b0b9d14ecd02b527184c /llvm/lib | |
parent | 2e4159801d8588b50b126af4e3233e03f6725f2e (diff) | |
download | bcm5719-llvm-208ddc5bdc554ed7c90d4515a04bb8f720b82213.tar.gz bcm5719-llvm-208ddc5bdc554ed7c90d4515a04bb8f720b82213.zip |
DAG: correctly legalize UMULO.
We were incorrectly sign extending into the high word (as you would for
SMULO) when legalizing UMULO in terms of a wider full multiplication.
Patch by James Duley.
llvm-svn: 305800
Diffstat (limited to 'llvm/lib')
-rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp | 29 |
1 files changed, 18 insertions, 11 deletions
diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp index 15e87b7af18..873b2bd48f1 100644 --- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp @@ -3530,17 +3530,24 @@ bool SelectionDAGLegalize::ExpandNode(SDNode *Node) { LC = RTLIB::MUL_I128; assert(LC != RTLIB::UNKNOWN_LIBCALL && "Cannot expand this operation!"); - // The high part is obtained by SRA'ing all but one of the bits of low - // part. - unsigned LoSize = VT.getSizeInBits(); - SDValue HiLHS = - DAG.getNode(ISD::SRA, dl, VT, LHS, - DAG.getConstant(LoSize - 1, dl, - TLI.getPointerTy(DAG.getDataLayout()))); - SDValue HiRHS = - DAG.getNode(ISD::SRA, dl, VT, RHS, - DAG.getConstant(LoSize - 1, dl, - TLI.getPointerTy(DAG.getDataLayout()))); + SDValue HiLHS; + SDValue HiRHS; + if (isSigned) { + // The high part is obtained by SRA'ing all but one of the bits of low + // part. + unsigned LoSize = VT.getSizeInBits(); + HiLHS = + DAG.getNode(ISD::SRA, dl, VT, LHS, + DAG.getConstant(LoSize - 1, dl, + TLI.getPointerTy(DAG.getDataLayout()))); + HiRHS = + DAG.getNode(ISD::SRA, dl, VT, RHS, + DAG.getConstant(LoSize - 1, dl, + TLI.getPointerTy(DAG.getDataLayout()))); + } else { + HiLHS = DAG.getConstant(0, dl, VT); + HiRHS = DAG.getConstant(0, dl, VT); + } // Here we're passing the 2 arguments explicitly as 4 arguments that are // pre-lowered to the correct types. This all depends upon WideVT not |