6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2025-01-05 12:31:33 +00:00
Code Issues Projects Releases Wiki Activity

Factor out some code into a helper function.

Browse Source 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41131 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2007-08-16 22:51:56 +00:00
parent fe5b4393d4
commit 1defe2df5d
1 changed files with 34 additions and 55 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

89
lib/Transforms/Scalar/GVN.cpp
View File

@ -672,6 +672,7 @@ namespace {
bool top_level = false);
void dump(DenseMap<BasicBlock*, Value*>& d);
bool iterateOnFunction(Function &F);
Value* CollapsePhi(PHINode* p);
};
char GVN::ID = 0;
@ -723,6 +724,21 @@ void GVN::dump(DenseMap<BasicBlock*, Value*>& d) {
printf("}\n");
}
Value* GVN::CollapsePhi(PHINode* p) {
DominatorTree &DT = getAnalysis<DominatorTree>();
Value* constVal = p->hasConstantValue();
if (constVal) {
if (Instruction* inst = dyn_cast<Instruction>(constVal)) {
if (DT.dominates(inst, p))
return inst;
} else {
return constVal;
}
}
return 0;
}
/// GetValueForBlock - Get the value to use within the specified basic block.
/// available values are in Phis.
@ -757,52 +773,23 @@ Value *GVN::GetValueForBlock(BasicBlock *BB, LoadInst* orig,
}
// Attempt to collapse PHI nodes that are trivially redundant
Value* v = PN->hasConstantValue();
Value* v = CollapsePhi(PN);
if (v) {
if (Instruction* inst = dyn_cast<Instruction>(v)) {
DominatorTree &DT = getAnalysis<DominatorTree>();
if (DT.dominates(inst, PN)) {
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
MD.removeInstruction(PN);
PN->replaceAllUsesWith(inst);
MD.removeInstruction(PN);
PN->replaceAllUsesWith(v);
SmallVector<BasicBlock*, 4> toRemove;
for (DenseMap<BasicBlock*, Value*>::iterator I = Phis.begin(),
E = Phis.end(); I != E; ++I)
if (I->second == PN)
toRemove.push_back(I->first);
for (SmallVector<BasicBlock*, 4>::iterator I = toRemove.begin(),
E= toRemove.end(); I != E; ++I)
Phis[*I] = inst;
for (DenseMap<BasicBlock*, Value*>::iterator I = Phis.begin(),
E = Phis.end(); I != E; ++I)
if (I->second == PN)
I->second = v;
PN->eraseFromParent();
PN->eraseFromParent();
Phis[BB] = inst;
Phis[BB] = v;
return inst;
}
} else {
MemoryDependenceAnalysis& MD = getAnalysis<MemoryDependenceAnalysis>();
MD.removeInstruction(PN);
PN->replaceAllUsesWith(v);
SmallVector<BasicBlock*, 4> toRemove;
for (DenseMap<BasicBlock*, Value*>::iterator I = Phis.begin(),
E = Phis.end(); I != E; ++I)
if (I->second == PN)
toRemove.push_back(I->first);
for (SmallVector<BasicBlock*, 4>::iterator I = toRemove.begin(),
E= toRemove.end(); I != E; ++I)
Phis[*I] = v;
PN->eraseFromParent();
Phis[BB] = v;
return v;
}
return v;
}
// Cache our phi construction results
@ -960,24 +947,16 @@ bool GVN::processInstruction(Instruction* I,
// Collapse PHI nodes
if (PHINode* p = dyn_cast<PHINode>(I)) {
Value* constVal = p->hasConstantValue();
Value* constVal = CollapsePhi(p);
if (constVal) {
if (Instruction* inst = dyn_cast<Instruction>(constVal)) {
DominatorTree &DT = getAnalysis<DominatorTree>();
if (DT.dominates(inst, p)) {
for (PhiMapType::iterator PI = phiMap.begin(), PE = phiMap.end();
PI != PE; ++PI)
if (PI->second.count(p))
PI->second.erase(p);
for (PhiMapType::iterator PI = phiMap.begin(), PE = phiMap.end();
PI != PE; ++PI)
if (PI->second.count(p))
PI->second.erase(p);
p->replaceAllUsesWith(inst);
toErase.push_back(p);
}
} else {
p->replaceAllUsesWith(constVal);
toErase.push_back(p);
}
p->replaceAllUsesWith(constVal);
toErase.push_back(p);
}
// Perform value-number based elimination
} else if (currAvail.test(num)) {