[PowerPC] Add implicit ops to conditional returns in PPCEarlyReturn

When PPCEarlyReturn, it should really copy implicit ops from the old return
instruction to the new one. This currently does not matter much, because we run
PPCEarlyReturn very late in the pipeline (there is nothing to do DCE on
definitions of those registers). However, for completeness, we should do it
anyway.

Noticed by inspection (and there should be no functional change); thus, no
test case.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@227763 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Hal Finkel 2015-02-01 20:16:10 +00:00
parent c400986f57
commit 604e1b770c

View File

@ -2150,11 +2150,14 @@ protected:
PIE = ReturnMBB.pred_end(); PI != PIE; ++PI) {
bool OtherReference = false, BlockChanged = false;
for (MachineBasicBlock::iterator J = (*PI)->getLastNonDebugInstr();;) {
MachineInstrBuilder MIB;
if (J->getOpcode() == PPC::B) {
if (J->getOperand(0).getMBB() == &ReturnMBB) {
// This is an unconditional branch to the return. Replace the
// branch with a blr.
BuildMI(**PI, J, J->getDebugLoc(), TII->get(I->getOpcode()));
MIB =
BuildMI(**PI, J, J->getDebugLoc(), TII->get(I->getOpcode()));
MIB.copyImplicitOps(I);
MachineBasicBlock::iterator K = J--;
K->eraseFromParent();
BlockChanged = true;
@ -2165,9 +2168,10 @@ protected:
if (J->getOperand(2).getMBB() == &ReturnMBB) {
// This is a conditional branch to the return. Replace the branch
// with a bclr.
BuildMI(**PI, J, J->getDebugLoc(), TII->get(PPC::BCCLR))
.addImm(J->getOperand(0).getImm())
.addReg(J->getOperand(1).getReg());
MIB = BuildMI(**PI, J, J->getDebugLoc(), TII->get(PPC::BCCLR))
.addImm(J->getOperand(0).getImm())
.addReg(J->getOperand(1).getReg());
MIB.copyImplicitOps(I);
MachineBasicBlock::iterator K = J--;
K->eraseFromParent();
BlockChanged = true;
@ -2178,10 +2182,11 @@ protected:
if (J->getOperand(1).getMBB() == &ReturnMBB) {
// This is a conditional branch to the return. Replace the branch
// with a bclr.
BuildMI(**PI, J, J->getDebugLoc(),
TII->get(J->getOpcode() == PPC::BC ?
PPC::BCLR : PPC::BCLRn))
.addReg(J->getOperand(0).getReg());
MIB = BuildMI(**PI, J, J->getDebugLoc(),
TII->get(J->getOpcode() == PPC::BC ?
PPC::BCLR : PPC::BCLRn))
.addReg(J->getOperand(0).getReg());
MIB.copyImplicitOps(I);
MachineBasicBlock::iterator K = J--;
K->eraseFromParent();
BlockChanged = true;