6502/llvm-6502
1
0
Fork 0
mirror of https://github.com/c64scene-ar/llvm-6502.git synced 2024-12-15 20:29:48 +00:00
Code Issues Projects Releases Wiki Activity

Tighten the conditions under which we do PRE, remove some unneeded code, and correct our preserved analyses list, since we

Browse Source 
do now change the CFG by splitting critical edges during PRE.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52631 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2008-06-23 17:49:45 +00:00
parent 2a6a645709
commit b70a571c99
1 changed files with 10 additions and 12 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

22
lib/Transforms/Scalar/GVN.cpp
View File

@ -719,10 +719,11 @@ namespace {
// This transformation requires dominator postdominator info // This transformation requires dominator postdominator info
virtual void getAnalysisUsage(AnalysisUsage &AU) const { virtual void getAnalysisUsage(AnalysisUsage &AU) const {
AU.setPreservesCFG();
AU.addRequired<DominatorTree>(); AU.addRequired<DominatorTree>();
AU.addRequired<MemoryDependenceAnalysis>(); AU.addRequired<MemoryDependenceAnalysis>();
AU.addRequired<AliasAnalysis>(); AU.addRequired<AliasAnalysis>();
AU.addPreserved<DominatorTree>();
AU.addPreserved<AliasAnalysis>(); AU.addPreserved<AliasAnalysis>();
AU.addPreserved<MemoryDependenceAnalysis>(); AU.addPreserved<MemoryDependenceAnalysis>();
} }
@ -1019,7 +1020,11 @@ bool GVN::processLoad(LoadInst *L, DenseMap<Value*, LoadInst*> &lastLoad,
} }
Value* GVN::lookupNumber(BasicBlock* BB, uint32_t num) { Value* GVN::lookupNumber(BasicBlock* BB, uint32_t num) {
ValueNumberScope* locals = localAvail[BB]; DenseMap<BasicBlock*, ValueNumberScope*>::iterator I = localAvail.find(BB);
if (I == localAvail.end())
return 0;
ValueNumberScope* locals = I->second;
while (locals) { while (locals) {
DenseMap<uint32_t, Value*>::iterator I = locals->table.find(num); DenseMap<uint32_t, Value*>::iterator I = locals->table.find(num);
@ -1167,9 +1172,9 @@ bool GVN::performPRE(Function& F) {
for (BasicBlock::iterator BI = CurrentBlock->begin(), for (BasicBlock::iterator BI = CurrentBlock->begin(),
BE = CurrentBlock->end(); BI != BE; ) { BE = CurrentBlock->end(); BI != BE; ) {
if (isa<AllocaInst>(BI) || isa<TerminatorInst>(BI) || if (isa<AllocationInst>(BI) || isa<TerminatorInst>(BI) ||
isa<LoadInst>(BI) || isa<StoreInst>(BI) || isa<PHINode>(BI) || BI->mayReadFromMemory() ||
isa<CallInst>(BI) || isa<PHINode>(BI)) { BI->mayWriteToMemory()) {
BI++; BI++;
continue; continue;
} }
@ -1282,13 +1287,6 @@ bool GVN::performPRE(Function& F) {
Phi->addIncoming(predMap[*PI], *PI); Phi->addIncoming(predMap[*PI], *PI);
VN.add(Phi, valno); VN.add(Phi, valno);
// The newly created PHI completely replaces the old instruction,
// so we need to update the maps to reflect this.
DomTreeNode* DTN = getAnalysis<DominatorTree>()[CurrentBlock];
for (DomTreeNode::iterator UI = DTN->begin(), UE = DTN->end();
UI != UE; ++UI)
localAvail[(*UI)->getBlock()]->table[valno] = Phi;
localAvail[CurrentBlock]->table[valno] = Phi; localAvail[CurrentBlock]->table[valno] = Phi;
BI->replaceAllUsesWith(Phi); BI->replaceAllUsesWith(Phi);