Handle cases when joining live intervals of two virtual registers.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@34534 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2007-02-23 20:40:13 +00:00
parent 2a27a7598b
commit da2295e631

View File

@ -960,21 +960,31 @@ bool LiveIntervals::JoinCopy(MachineInstr *CopyMI,
DOUT << "\n\t\tJoined. Result = "; DestInt.print(DOUT, mri_);
DOUT << "\n";
// If the intervals were swapped by Join, swap them back so that the register
// mapping (in the r2i map) is correct.
if (Swapped) SrcInt.swap(DestInt);
// Live range has been lengthened due to colaescing, eliminate the
// unnecessary kills at the end of the source live ranges.
LiveVariables::VarInfo& vi = lv_->getVarInfo(repSrcReg);
for (unsigned i = 0, e = vi.Kills.size(); i != e; ++i) {
MachineInstr *Kill = vi.Kills[i];
LiveVariables::VarInfo& svi = lv_->getVarInfo(repSrcReg);
for (unsigned i = 0, e = svi.Kills.size(); i != e; ++i) {
MachineInstr *Kill = svi.Kills[i];
if (Kill == CopyMI || isRemoved(Kill))
continue;
if (DestInt.liveAt(getInstructionIndex(Kill) + InstrSlots::NUM))
unsetRegisterKill(Kill, repSrcReg);
}
if (MRegisterInfo::isVirtualRegister(repDstReg)) {
// If both are virtual registers...
LiveVariables::VarInfo& dvi = lv_->getVarInfo(repDstReg);
for (unsigned i = 0, e = dvi.Kills.size(); i != e; ++i) {
MachineInstr *Kill = dvi.Kills[i];
if (Kill == CopyMI || isRemoved(Kill))
continue;
if (DestInt.liveAt(getInstructionIndex(Kill) + InstrSlots::NUM))
unsetRegisterKill(Kill, repDstReg);
}
}
// If the intervals were swapped by Join, swap them back so that the register
// mapping (in the r2i map) is correct.
if (Swapped) SrcInt.swap(DestInt);
removeInterval(repSrcReg);
r2rMap_[repSrcReg] = repDstReg;