Remove the hack that turned an {S,U}MUL_LOHI with an unused high

result into a MUL late in the X86 codegen process. ISD::MUL is
once again Legal on X86, so this is no longer needed. And, the
hack was suboptimal; see PR1874 for details.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@47567 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Dan Gohman 2008-02-25 21:57:04 +00:00
parent f6283fd27b
commit fcf81db600

View File

@ -1224,15 +1224,6 @@ SDNode *X86DAGToDAGISel::Select(SDOperand N) {
SDOperand N0 = Node->getOperand(0);
SDOperand N1 = Node->getOperand(1);
// There are several forms of IMUL that just return the low part and
// don't have fixed-register operands. If we don't need the high part,
// use these instead. They can be selected with the generated ISel code.
if (NVT != MVT::i8 &&
N.getValue(1).use_empty()) {
N = CurDAG->getNode(ISD::MUL, NVT, N0, N1);
break;
}
bool isSigned = Opcode == ISD::SMUL_LOHI;
if (!isSigned)
switch (NVT) {