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[X86] Remove more dead code left over from the handling of i8/i16 UMUL_LOHI/SMUL_LOHI that is no longer needed. NFC 

llvm-svn: 329152
This commit is contained in:
Craig Topper 2018-04-04 07:00:16 +00:00
parent 2a0ea0105d
commit 88e38e3e3e
1 changed files with 0 additions and 21 deletions
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21
llvm/lib/Target/X86/X86ISelDAGToDAG.cpp
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@ -2901,27 +2901,6 @@ void X86DAGToDAGISel::Select(SDNode *Node) {
}
}
// Prevent use of AH in a REX instruction by referencing AX instead.
if (HiReg == X86::AH && Subtarget->is64Bit() &&
!SDValue(Node, 1).use_empty()) {
SDValue Result = CurDAG->getCopyFromReg(CurDAG->getEntryNode(), dl,
X86::AX, MVT::i16, InFlag);
InFlag = Result.getValue(2);
// Get the low part if needed. Don't use getCopyFromReg for aliasing
// registers.
if (!SDValue(Node, 0).use_empty())
ReplaceUses(SDValue(Node, 0),
CurDAG->getTargetExtractSubreg(X86::sub_8bit, dl, MVT::i8, Result));
// Shift AX down 8 bits.
Result = SDValue(CurDAG->getMachineNode(X86::SHR16ri, dl, MVT::i16,
Result,
CurDAG->getTargetConstant(8, dl, MVT::i8)),
0);
// Then truncate it down to i8.
ReplaceUses(SDValue(Node, 1),
CurDAG->getTargetExtractSubreg(X86::sub_8bit, dl, MVT::i8, Result));
}
// Copy the low half of the result, if it is needed.
if (!SDValue(Node, 0).use_empty()) {
if (!ResLo.getNode()) {