Fixes for BreakCriticalMachineCodeEdge by Fernando.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@46419 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2008-01-27 19:51:03 +00:00
parent c837abee2f
commit 24387df207

View File

@ -33,13 +33,14 @@ MachineBasicBlock* SplitCriticalMachineEdge(MachineBasicBlock* src,
// insert the new block into the machine function.
src->getParent()->getBasicBlockList().insert(src->getParent()->end(),
crit_mbb);
crit_mbb);
// insert a unconditional branch linking the new block to dst
const TargetMachine& TM = src->getParent()->getTarget();
const TargetInstrInfo* TII = TM.getInstrInfo();
std::vector<MachineOperand> emptyConditions;
TII->InsertBranch(*crit_mbb, dst, (MachineBasicBlock*)0, emptyConditions);
TII->InsertBranch(*crit_mbb, dst, (MachineBasicBlock*)0,
emptyConditions);
// modify every branch in src that points to dst to point to the new
// machine basic block instead:
@ -48,18 +49,18 @@ MachineBasicBlock* SplitCriticalMachineEdge(MachineBasicBlock* src,
while (mii != src->begin()) {
mii--;
// if there are no more branches, finish the loop
if (!TII->isTerminatorInstr(mii->getOpcode())) {
if (!mii->getDesc().isTerminator()) {
break;
}
// Scan the operands of this branch, replacing any uses of dst with
// crit_mbb.
for (unsigned i = 0, e = mii->getNumOperands(); i != e; ++i) {
MachineOperand & mo = mii->getOperand(i);
if (mo.isMachineBasicBlock() &&
mo.getMachineBasicBlock() == dst) {
mo.getMBB() == dst) {
found_branch = true;
mo.setMachineBasicBlock(crit_mbb);
mo.setMBB(crit_mbb);
}
}
}
@ -68,7 +69,8 @@ MachineBasicBlock* SplitCriticalMachineEdge(MachineBasicBlock* src,
// I am inserting too many gotos, but I am trusting that the asm printer
// will optimize the unnecessary gotos.
if(!found_branch) {
TII->InsertBranch(*src, crit_mbb, (MachineBasicBlock*)0, emptyConditions);
TII->InsertBranch(*src, crit_mbb, (MachineBasicBlock*)0,
emptyConditions);
}
/// Change all the phi functions in dst, so that the incoming block be
@ -77,29 +79,28 @@ MachineBasicBlock* SplitCriticalMachineEdge(MachineBasicBlock* src,
/// the first instructions are always phi functions.
if(mii->getOpcode() != TargetInstrInfo::PHI)
break;
// Find the operands corresponding to the source block
std::vector<unsigned> toRemove;
unsigned reg = 0;
for (unsigned u = 0; u != mii->getNumOperands(); ++u)
if (mii->getOperand(u).isMachineBasicBlock() &&
mii->getOperand(u).getMachineBasicBlock() == src) {
mii->getOperand(u).getMBB() == src) {
reg = mii->getOperand(u-1).getReg();
toRemove.push_back(u-1);
}
// Remove all uses of this MBB
for (std::vector<unsigned>::reverse_iterator I = toRemove.rbegin(),
E = toRemove.rend(); I != E; ++I) {
mii->RemoveOperand(*I+1);
mii->RemoveOperand(*I);
}
// Add a single use corresponding to the new MBB
mii->addRegOperand(reg, false);
mii->addMachineBasicBlockOperand(crit_mbb);
mii->addOperand(MachineOperand::CreateReg(reg, false));
mii->addOperand(MachineOperand::CreateMBB(crit_mbb));
}
return crit_mbb;
}