Don't attempt trivial coalescing for sub-register copies.

Patch by Krister Wombell!

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@119791 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Jakob Stoklund Olesen 2010-11-19 05:45:24 +00:00
parent 528900d9a4
commit e7fbdcdfc6

View File

@ -466,6 +466,10 @@ unsigned RALinScan::attemptTrivialCoalescing(LiveInterval &cur, unsigned Reg) {
CandReg = CopyMI->getOperand(0).getReg();
else
return Reg;
// If the target of the copy is a sub-register then don't coalesce.
if(CopyMI->getOperand(0).getSubReg())
return Reg;
}
if (TargetRegisterInfo::isVirtualRegister(CandReg)) {