Correctly handle replacement and removal of PHIs with one incoming register.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@54374 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2008-08-05 21:40:45 +00:00
parent 021507be82
commit 5d2f8072d4

View File

@ -27,6 +27,7 @@
#include "llvm/Pass.h"
#include "llvm/Type.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Target/TargetInstrInfo.h"
@ -128,10 +129,15 @@ bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
start->RemoveOperand(i-1);
}
if (start->getNumOperands() == 1) {
if (start->getNumOperands() == 3) {
MachineInstr* phi = start;
unsigned Input = phi->getOperand(1).getReg();
unsigned Output = phi->getOperand(0).getReg();
start++;
phi->eraseFromParent();
F.getRegInfo().replaceRegWith(Output, Input);
} else
start++;
}