[MIPS] BuildCondBr should preserve MO flags
While simplifying branches in the MachineInstr representation, the
routine BuildCondBr must preserve flags on register MachineOperands. In
particular, it must preserve the <undef> flag.
This fixes a bug that is unlikely to occur in any real scenario, but
which bugpoint is likely to introduce.
Patch By Nick Johnson!
Reviewers: ahatanak, sdardis
Differential Revision: https://reviews.llvm.org/D34041
llvm-svn: 305290
diff --git a/llvm/lib/Target/Mips/MipsInstrInfo.cpp b/llvm/lib/Target/Mips/MipsInstrInfo.cpp
index df62c66..4adf77f 100644
--- a/llvm/lib/Target/Mips/MipsInstrInfo.cpp
+++ b/llvm/lib/Target/Mips/MipsInstrInfo.cpp
@@ -103,12 +103,9 @@
MachineInstrBuilder MIB = BuildMI(&MBB, DL, MCID);
for (unsigned i = 1; i < Cond.size(); ++i) {
- if (Cond[i].isReg())
- MIB.addReg(Cond[i].getReg());
- else if (Cond[i].isImm())
- MIB.addImm(Cond[i].getImm());
- else
- assert(false && "Cannot copy operand");
+ assert((Cond[i].isImm() || Cond[i].isReg()) &&
+ "Cannot copy operand for conditional branch!");
+ MIB.add(Cond[i]);
}
MIB.addMBB(TBB);
}