namespace {
/// BranchFolderPass - Wrap branch folder in a machine function pass.
- class BranchFolderPass : public MachineFunctionPass,
- public BranchFolder {
+ class BranchFolderPass : public MachineFunctionPass {
public:
static char ID;
- explicit BranchFolderPass(bool defaultEnableTailMerge)
- : MachineFunctionPass(ID), BranchFolder(defaultEnableTailMerge, true) {}
+ explicit BranchFolderPass(): MachineFunctionPass(ID) {}
virtual bool runOnMachineFunction(MachineFunction &MF);
- virtual const char *getPassName() const { return "Control Flow Optimizer"; }
+
+ virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.addRequired<TargetPassConfig>();
+ MachineFunctionPass::getAnalysisUsage(AU);
+ }
};
}
char BranchFolderPass::ID = 0;
+char &llvm::BranchFolderPassID = BranchFolderPass::ID;
-FunctionPass *llvm::createBranchFoldingPass(bool DefaultEnableTailMerge) {
- return new BranchFolderPass(DefaultEnableTailMerge);
-}
+INITIALIZE_PASS(BranchFolderPass, "branch-folder",
+ "Control Flow Optimizer", false, false)
bool BranchFolderPass::runOnMachineFunction(MachineFunction &MF) {
- return OptimizeFunction(MF,
- MF.getTarget().getInstrInfo(),
- MF.getTarget().getRegisterInfo(),
- getAnalysisIfAvailable<MachineModuleInfo>());
+ TargetPassConfig *PassConfig = &getAnalysis<TargetPassConfig>();
+ BranchFolder Folder(PassConfig->getEnableTailMerge(), /*CommonHoist=*/true);
+ return Folder.OptimizeFunction(MF,
+ MF.getTarget().getInstrInfo(),
+ MF.getTarget().getRegisterInfo(),
+ getAnalysisIfAvailable<MachineModuleInfo>());
}
delete RS;
return MadeChange;
}
-
+
// Walk the function to find jump tables that are live.
BitVector JTIsLive(JTI->getJumpTables().size());
for (MachineFunction::iterator BB = MF.begin(), E = MF.end();
for (; I != E; ++I) {
if (I->isDebugValue())
continue;
- const MCInstrDesc &MCID = I->getDesc();
- if (MCID.isCall())
+ if (I->isCall())
Time += 10;
- else if (MCID.mayLoad() || MCID.mayStore())
+ else if (I->mayLoad() || I->mayStore())
Time += 2;
else
++Time;
// an object with itself.
#ifndef _GLIBCXX_DEBUG
llvm_unreachable("Predecessor appears twice");
-#endif
+#else
return false;
+#endif
}
}
break;
}
--I;
- if (!I->getDesc().isTerminator()) break;
+ if (!I->isTerminator()) break;
++NumTerms;
}
return NumTerms;
// heuristics.
unsigned EffectiveTailLen = CommonTailLen;
if (SuccBB && MBB1 != PredBB && MBB2 != PredBB &&
- !MBB1->back().getDesc().isBarrier() &&
- !MBB2->back().getDesc().isBarrier())
+ !MBB1->back().isBarrier() &&
+ !MBB2->back().isBarrier())
++EffectiveTailLen;
// Check if the common tail is long enough to be worthwhile.
// Visit each predecessor only once.
if (!UniquePreds.insert(PBB))
continue;
+ // Skip blocks which may jump to a landing pad. Can't tail merge these.
+ if (PBB->getLandingPadSuccessor())
+ continue;
MachineBasicBlock *TBB = 0, *FBB = 0;
SmallVector<MachineOperand, 4> Cond;
if (!TII->AnalyzeBranch(*PBB, TBB, FBB, Cond, true)) {
if (MergePotentials.size() >= 2)
MadeChange |= TryTailMergeBlocks(IBB, PredBB);
// Reinsert an unconditional branch if needed.
- // The 1 below can occur as a result of removing blocks in TryTailMergeBlocks.
- PredBB = prior(I); // this may have been changed in TryTailMergeBlocks
+ // The 1 below can occur as a result of removing blocks in
+ // TryTailMergeBlocks.
+ PredBB = prior(I); // this may have been changed in TryTailMergeBlocks
if (MergePotentials.size() == 1 &&
MergePotentials.begin()->getBlock() != PredBB)
FixTail(MergePotentials.begin()->getBlock(), IBB, TII);
if (!MBBI->isDebugValue())
break;
}
- return (MBBI->getDesc().isBranch());
+ return (MBBI->isBranch());
}
/// IsBetterFallthrough - Return true if it would be clearly better to
MachineBasicBlock::iterator MBB2I = --MBB2->end();
while (MBB2I->isDebugValue())
--MBB2I;
- return MBB2I->getDesc().isCall() && !MBB1I->getDesc().isCall();
+ return MBB2I->isCall() && !MBB1I->isCall();
}
/// OptimizeBlock - Analyze and optimize control flow related to the specified
MachineBasicBlock::iterator PrevBBIter = PrevBB.end();
--PrevBBIter;
MachineBasicBlock::iterator MBBIter = MBB->begin();
- // Check if DBG_VALUE at the end of PrevBB is identical to the
+ // Check if DBG_VALUE at the end of PrevBB is identical to the
// DBG_VALUE at the beginning of MBB.
while (PrevBBIter != PrevBB.begin() && MBBIter != MBB->end()
&& PrevBBIter->isDebugValue() && MBBIter->isDebugValue()) {
IsSafe = false;
break;
}
+
+ if (MO.isKill() && Uses.count(Reg))
+ // Kills a register that's read by the instruction at the point of
+ // insertion. Remove the kill marker.
+ MO.setIsKill(false);
}
}
if (!IsSafe)