#include "llvm/Pass.h"
#include "llvm/Type.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/Support/CFG.h"
#include "llvm/Support/Compiler.h"
BasicBlock *BB = I;
DeadBlocks.push_back(BB);
while (PHINode *PN = dyn_cast<PHINode>(BB->begin())) {
- PN->replaceAllUsesWith(Constant::getNullValue(PN->getType()));
+ PN->replaceAllUsesWith(Context->getNullValue(PN->getType()));
BB->getInstList().pop_front();
}
for (succ_iterator SI = succ_begin(BB), E = succ_end(BB); SI != E; ++SI)
namespace {
- class VISIBILITY_HIDDEN UnreachableMachineBlockElim :
+ class VISIBILITY_HIDDEN UnreachableMachineBlockElim :
public MachineFunctionPass {
virtual bool runOnMachineFunction(MachineFunction &F);
-
+ MachineModuleInfo *MMI;
public:
static char ID; // Pass identification, replacement for typeid
UnreachableMachineBlockElim() : MachineFunctionPass(&ID) {}
bool UnreachableMachineBlockElim::runOnMachineFunction(MachineFunction &F) {
SmallPtrSet<MachineBasicBlock*, 8> Reachable;
+ MMI = getAnalysisIfAvailable<MachineModuleInfo>();
+
// Mark all reachable blocks.
for (df_ext_iterator<MachineFunction*, SmallPtrSet<MachineBasicBlock*, 8> >
I = df_ext_begin(&F, Reachable), E = df_ext_end(&F, Reachable);
std::vector<MachineBasicBlock*> DeadBlocks;
for (MachineFunction::iterator I = F.begin(), E = F.end(); I != E; ++I) {
MachineBasicBlock *BB = I;
-
+
// Test for deadness.
if (!Reachable.count(BB)) {
DeadBlocks.push_back(BB);
-
+
while (BB->succ_begin() != BB->succ_end()) {
MachineBasicBlock* succ = *BB->succ_begin();
-
+
MachineBasicBlock::iterator start = succ->begin();
while (start != succ->end() &&
start->getOpcode() == TargetInstrInfo::PHI) {
for (unsigned i = start->getNumOperands() - 1; i >= 2; i-=2)
- if (start->getOperand(i).isMachineBasicBlock() &&
+ if (start->getOperand(i).isMBB() &&
start->getOperand(i).getMBB() == BB) {
start->RemoveOperand(i);
start->RemoveOperand(i-1);
}
-
+
start++;
}
-
+
BB->removeSuccessor(BB->succ_begin());
}
}
}
// Actually remove the blocks now.
- for (unsigned i = 0, e = DeadBlocks.size(); i != e; ++i)
- DeadBlocks[i]->eraseFromParent();
+ for (unsigned i = 0, e = DeadBlocks.size(); i != e; ++i) {
+ MachineBasicBlock *MBB = DeadBlocks[i];
+ // If there are any labels in the basic block, unregister them from
+ // MachineModuleInfo.
+ if (MMI && !MBB->empty()) {
+ for (MachineBasicBlock::iterator I = MBB->begin(),
+ E = MBB->end(); I != E; ++I) {
+ if (I->isLabel())
+ // The label ID # is always operand #0, an immediate.
+ MMI->InvalidateLabel(I->getOperand(0).getImm());
+ }
+ }
+ MBB->eraseFromParent();
+ }
// Cleanup PHI nodes.
for (MachineFunction::iterator I = F.begin(), E = F.end(); I != E; ++I) {
MachineBasicBlock *BB = I;
// Prune unneeded PHI entries.
- SmallPtrSet<MachineBasicBlock*, 8> preds(BB->pred_begin(),
+ SmallPtrSet<MachineBasicBlock*, 8> preds(BB->pred_begin(),
BB->pred_end());
MachineBasicBlock::iterator phi = BB->begin();
while (phi != BB->end() &&
phi->RemoveOperand(i);
phi->RemoveOperand(i-1);
}
-
+
if (phi->getNumOperands() == 3) {
unsigned Input = phi->getOperand(1).getReg();
unsigned Output = phi->getOperand(0).getReg();
continue;
}
-
+
++phi;
}
}
return DeadBlocks.size();
}
-