Fix bug: test/Regression/Assembler/2002-08-22-DominanceProblem.ll

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3474 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2002-08-22 20:39:29 +00:00
parent e6d2fdff26
commit 80b7f8ceb4

View File

@ -36,21 +36,15 @@ bool DominatorSetBase::dominates(Instruction *A, Instruction *B) const {
return &*I == A;
}
// runOnFunction - This method calculates the forward dominator sets for the
// specified function.
//
bool DominatorSet::runOnFunction(Function &F) {
Doms.clear(); // Reset from the last time we were run...
Root = &F.getEntryNode();
assert(pred_begin(Root) == pred_end(Root) &&
"Root node has predecessors in function!");
void DominatorSet::calculateDominatorsFromBlock(BasicBlock *RootBB) {
bool Changed;
Doms[RootBB].insert(RootBB); // Root always dominates itself...
do {
Changed = false;
DomSetType WorkingSet;
df_iterator<Function*> It = df_begin(&F), End = df_end(&F);
df_iterator<BasicBlock*> It = df_begin(RootBB), End = df_end(RootBB);
for ( ; It != End; ++It) {
BasicBlock *BB = *It;
pred_iterator PI = pred_begin(BB), PEnd = pred_end(BB);
@ -78,16 +72,32 @@ bool DominatorSet::runOnFunction(Function &F) {
WorkingSet.clear(); // Clear out the set for next iteration
}
} while (Changed);
}
// runOnFunction - This method calculates the forward dominator sets for the
// specified function.
//
bool DominatorSet::runOnFunction(Function &F) {
Doms.clear(); // Reset from the last time we were run...
Root = &F.getEntryNode();
assert(pred_begin(Root) == pred_end(Root) &&
"Root node has predecessors in function!");
// Calculate dominator sets for the reachable basic blocks...
calculateDominatorsFromBlock(Root);
// Every basic block in the function should at least dominate themselves, and
// thus every basic block should have an entry in Doms. The one case where we
// miss this is when a basic block is unreachable. To get these we now do an
// extra pass adding self dominance info to the DomSet if the block doesn't
// already have an entry.
// extra pass over the function, calculating dominator information for
// unreachable blocks.
//
for (Function::iterator I = F.begin(), E = F.end(); I != E; ++I)
if (Doms[I].empty())
Doms[I].insert(I);
if (Doms[I].empty()) {
calculateDominatorsFromBlock(I);
}
return false;
}