[TargetInstrInfo] Fix the implementation of commuteInstruction to match the

comment of the API.

Relaxes the behavior of TargetInstrInfo::commuteInstruction when
TargetInstrInfo::findCommutedOpIndices returns false.

Previously TargetInstrInfo triggered a fatal error in such situation whereas based
on the comment in the API it should just return nullptr. Indeed the only
precondition that should be ensured is that the instruction must be commutable.

llvm-svn: 208371
This commit is contained in:
Quentin Colombet 2014-05-08 23:12:27 +00:00
parent 54a824b758
commit 2eb151e29f
1 changed files with 2 additions and 4 deletions

View File

@ -127,10 +127,8 @@ MachineInstr *TargetInstrInfo::commuteInstruction(MachineInstr *MI,
return nullptr;
unsigned Idx1, Idx2;
if (!findCommutedOpIndices(MI, Idx1, Idx2)) {
std::string msg;
raw_string_ostream Msg(msg);
Msg << "Don't know how to commute: " << *MI;
report_fatal_error(Msg.str());
assert(MI->isCommutable() && "Precondition violation: MI must be commutable.");
return nullptr;
}
assert(MI->getOperand(Idx1).isReg() && MI->getOperand(Idx2).isReg() &&