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Clean whitespaces.

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git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@160668 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Nadav Rotem
2012-07-24 10:51:42 +00:00
parent 8899d5c6fb
commit a94d6e87c4
22 changed files with 500 additions and 498 deletions
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66
lib/Transforms/Scalar/Sink.cpp
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@ -40,9 +40,9 @@ namespace {
Sinking() : FunctionPass(ID) {
initializeSinkingPass(*PassRegistry::getPassRegistry());
}
virtual bool runOnFunction(Function &F);
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
FunctionPass::getAnalysisUsage(AU);
@ -59,7 +59,7 @@ namespace {
bool IsAcceptableTarget(Instruction *Inst, BasicBlock *SuccToSinkTo) const;
};
} // end anonymous namespace
char Sinking::ID = 0;
INITIALIZE_PASS_BEGIN(Sinking, "sink", "Code sinking", false, false)
INITIALIZE_PASS_DEPENDENCY(LoopInfo)
@ -71,7 +71,7 @@ FunctionPass *llvm::createSinkingPass() { return new Sinking(); }
/// AllUsesDominatedByBlock - Return true if all uses of the specified value
/// occur in blocks dominated by the specified block.
bool Sinking::AllUsesDominatedByBlock(Instruction *Inst,
bool Sinking::AllUsesDominatedByBlock(Instruction *Inst,
BasicBlock *BB) const {
// Ignoring debug uses is necessary so debug info doesn't affect the code.
// This may leave a referencing dbg_value in the original block, before
@ -101,18 +101,18 @@ bool Sinking::runOnFunction(Function &F) {
AA = &getAnalysis<AliasAnalysis>();
bool MadeChange, EverMadeChange = false;
do {
MadeChange = false;
DEBUG(dbgs() << "Sinking iteration " << NumSinkIter << "\n");
// Process all basic blocks.
for (Function::iterator I = F.begin(), E = F.end();
for (Function::iterator I = F.begin(), E = F.end();
I != E; ++I)
MadeChange |= ProcessBlock(*I);
EverMadeChange |= MadeChange;
NumSinkIter++;
} while (MadeChange);
return EverMadeChange;
}
@ -121,8 +121,8 @@ bool Sinking::ProcessBlock(BasicBlock &BB) {
if (BB.getTerminator()->getNumSuccessors() <= 1 || BB.empty()) return false;
// Don't bother sinking code out of unreachable blocks. In addition to being
// unprofitable, it can also lead to infinite looping, because in an unreachable
// loop there may be nowhere to stop.
// unprofitable, it can also lead to infinite looping, because in an
// unreachable loop there may be nowhere to stop.
if (!DT->isReachableFromEntry(&BB)) return false;
bool MadeChange = false;
@ -134,7 +134,7 @@ bool Sinking::ProcessBlock(BasicBlock &BB) {
SmallPtrSet<Instruction *, 8> Stores;
do {
Instruction *Inst = I; // The instruction to sink.
// Predecrement I (if it's not begin) so that it isn't invalidated by
// sinking.
ProcessedBegin = I == BB.begin();
@ -146,10 +146,10 @@ bool Sinking::ProcessBlock(BasicBlock &BB) {
if (SinkInstruction(Inst, Stores))
++NumSunk, MadeChange = true;
// If we just processed the first instruction in the block, we're done.
} while (!ProcessedBegin);
return MadeChange;
}
@ -177,16 +177,17 @@ static bool isSafeToMove(Instruction *Inst, AliasAnalysis *AA,
/// IsAcceptableTarget - Return true if it is possible to sink the instruction
/// in the specified basic block.
bool Sinking::IsAcceptableTarget(Instruction *Inst, BasicBlock *SuccToSinkTo) const {
bool Sinking::IsAcceptableTarget(Instruction *Inst,
BasicBlock *SuccToSinkTo) const {
assert(Inst && "Instruction to be sunk is null");
assert(SuccToSinkTo && "Candidate sink target is null");
// It is not possible to sink an instruction into its own block. This can
// happen with loops.
if (Inst->getParent() == SuccToSinkTo)
return false;
// If the block has multiple predecessors, this would introduce computation
// If the block has multiple predecessors, this would introduce computation
// on different code paths. We could split the critical edge, but for now we
// just punt.
// FIXME: Split critical edges if not backedges.
@ -195,18 +196,19 @@ bool Sinking::IsAcceptableTarget(Instruction *Inst, BasicBlock *SuccToSinkTo) co
// other code paths.
if (!isSafeToSpeculativelyExecute(Inst))
return false;
// We don't want to sink across a critical edge if we don't dominate the
// successor. We could be introducing calculations to new code paths.
if (!DT->dominates(Inst->getParent(), SuccToSinkTo))
return false;
// Don't sink instructions into a loop.
Loop *succ = LI->getLoopFor(SuccToSinkTo), *cur = LI->getLoopFor(Inst->getParent());
Loop *succ = LI->getLoopFor(SuccToSinkTo);
Loop *cur = LI->getLoopFor(Inst->getParent());
if (succ != 0 && succ != cur)
return false;
}
// Finally, check that all the uses of the instruction are actually
// dominated by the candidate
return AllUsesDominatedByBlock(Inst, SuccToSinkTo);
@ -219,7 +221,7 @@ bool Sinking::SinkInstruction(Instruction *Inst,
// Check if it's safe to move the instruction.
if (!isSafeToMove(Inst, AA, Stores))
return false;
// FIXME: This should include support for sinking instructions within the
// block they are currently in to shorten the live ranges. We often get
// instructions sunk into the top of a large block, but it would be better to
@ -227,41 +229,41 @@ bool Sinking::SinkInstruction(Instruction *Inst,
// be careful not to *increase* register pressure though, e.g. sinking
// "x = y + z" down if it kills y and z would increase the live ranges of y
// and z and only shrink the live range of x.
// SuccToSinkTo - This is the successor to sink this instruction to, once we
// decide.
BasicBlock *SuccToSinkTo = 0;
// Instructions can only be sunk if all their uses are in blocks
// dominated by one of the successors.
// Look at all the postdominators and see if we can sink it in one.
DomTreeNode *DTN = DT->getNode(Inst->getParent());
for (DomTreeNode::iterator I = DTN->begin(), E = DTN->end();
for (DomTreeNode::iterator I = DTN->begin(), E = DTN->end();
I != E && SuccToSinkTo == 0; ++I) {
BasicBlock *Candidate = (*I)->getBlock();
if ((*I)->getIDom()->getBlock() == Inst->getParent() &&
if ((*I)->getIDom()->getBlock() == Inst->getParent() &&
IsAcceptableTarget(Inst, Candidate))
SuccToSinkTo = Candidate;
}
// If no suitable postdominator was found, look at all the successors and
// If no suitable postdominator was found, look at all the successors and
// decide which one we should sink to, if any.
for (succ_iterator I = succ_begin(Inst->getParent()),
for (succ_iterator I = succ_begin(Inst->getParent()),
E = succ_end(Inst->getParent()); I != E && SuccToSinkTo == 0; ++I) {
if (IsAcceptableTarget(Inst, *I))
SuccToSinkTo = *I;
}
// If we couldn't find a block to sink to, ignore this instruction.
if (SuccToSinkTo == 0)
return false;
DEBUG(dbgs() << "Sink" << *Inst << " (";
WriteAsOperand(dbgs(), Inst->getParent(), false);
WriteAsOperand(dbgs(), Inst->getParent(), false);
dbgs() << " -> ";
WriteAsOperand(dbgs(), SuccToSinkTo, false);
WriteAsOperand(dbgs(), SuccToSinkTo, false);
dbgs() << ")\n");
// Move the instruction.
Inst->moveBefore(SuccToSinkTo->getFirstInsertionPt());
return true;