Refactor some code, and fix test/Transforms/GVNPRE/2007-06-12-NoExit.ll by being more careful when using

post-dominator information.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37556 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2007-06-12 16:57:50 +00:00
parent 93f905daef
commit 239e71201e

View File

@ -131,6 +131,9 @@ namespace {
std::set<Value*>& currTemps,
std::set<Value*, ExprLT>& currAvail,
std::map<BasicBlock*, std::set<Value*, ExprLT> > availOut);
void cleanup();
void elimination(std::map<BasicBlock*,
std::set<Value*, ExprLT> >& availOut);
};
@ -482,6 +485,61 @@ void GVNPRE::CalculateAvailOut(DomTreeNode* DI,
}
}
void GVNPRE::elimination(std::map<BasicBlock*,
std::set<Value*, ExprLT> >& availableOut) {
DOUT << "\n\nPhase 3: Elimination\n\n";
std::vector<std::pair<Instruction*, Value*> > replace;
std::vector<Instruction*> erase;
DominatorTree& DT = getAnalysis<DominatorTree>();
for (df_iterator<DomTreeNode*> DI = df_begin(DT.getRootNode()),
E = df_end(DT.getRootNode()); DI != E; ++DI) {
BasicBlock* BB = DI->getBlock();
DOUT << "Block: " << BB->getName() << "\n";
dump_unique(availableOut[BB]);
DOUT << "\n\n";
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end();
BI != BE; ++BI) {
if (isa<BinaryOperator>(BI) || isa<CmpInst>(BI)) {
Value *leader = find_leader(availableOut[BB], BI);
if (leader != 0)
if (Instruction* Instr = dyn_cast<Instruction>(leader))
if (Instr->getParent() != 0 && Instr != BI) {
replace.push_back(std::make_pair(BI, leader));
erase.push_back(BI);
++NumEliminated;
}
}
}
}
while (!replace.empty()) {
std::pair<Instruction*, Value*> rep = replace.back();
replace.pop_back();
rep.first->replaceAllUsesWith(rep.second);
}
for (std::vector<Instruction*>::iterator I = erase.begin(), E = erase.end();
I != E; ++I)
(*I)->eraseFromParent();
}
void GVNPRE::cleanup() {
while (!createdExpressions.empty()) {
Instruction* I = createdExpressions.back();
createdExpressions.pop_back();
delete I;
}
}
bool GVNPRE::runOnFunction(Function &F) {
VN.clear();
MS.clear();
@ -517,7 +575,15 @@ bool GVNPRE::runOnFunction(Function &F) {
dump_unique(MS);
DOUT << "\n";
// If function has no exit blocks, only perform GVN
PostDominatorTree &PDT = getAnalysis<PostDominatorTree>();
if (PDT[&F.getEntryBlock()] == 0) {
elimination(availableOut);
cleanup();
return true;
}
// Phase 1, Part 2: calculate ANTIC_IN
@ -634,7 +700,6 @@ bool GVNPRE::runOnFunction(Function &F) {
DOUT << "\n";
}
// Phase 2: Insert
DOUT<< "\nPhase 2: Insertion\n";
@ -826,53 +891,10 @@ bool GVNPRE::runOnFunction(Function &F) {
}
// Phase 3: Eliminate
DOUT << "\n\nPhase 3: Elimination\n\n";
std::vector<std::pair<Instruction*, Value*> > replace;
std::vector<Instruction*> erase;
for (df_iterator<DomTreeNode*> DI = df_begin(DT.getRootNode()),
E = df_end(DT.getRootNode()); DI != E; ++DI) {
BasicBlock* BB = DI->getBlock();
DOUT << "Block: " << BB->getName() << "\n";
dump_unique(availableOut[BB]);
DOUT << "\n\n";
for (BasicBlock::iterator BI = BB->begin(), BE = BB->end();
BI != BE; ++BI) {
if (isa<BinaryOperator>(BI) || isa<CmpInst>(BI)) {
Value *leader = find_leader(availableOut[BB], BI);
if (leader != 0)
if (Instruction* Instr = dyn_cast<Instruction>(leader))
if (Instr->getParent() != 0 && Instr != BI) {
replace.push_back(std::make_pair(BI, leader));
erase.push_back(BI);
++NumEliminated;
}
}
}
}
while (!replace.empty()) {
std::pair<Instruction*, Value*> rep = replace.back();
replace.pop_back();
rep.first->replaceAllUsesWith(rep.second);
}
for (std::vector<Instruction*>::iterator I = erase.begin(), E = erase.end();
I != E; ++I)
(*I)->eraseFromParent();
elimination(availableOut);
// Phase 4: Cleanup
while (!createdExpressions.empty()) {
Instruction* I = createdExpressions.back();
createdExpressions.pop_back();
delete I;
}
cleanup();
return false;
return true;
}