#define LLVM_ANALYSIS_DOMINATORS_H
#include "llvm/Analysis/ET-Forest.h"
+#include "llvm/Function.h"
#include "llvm/Pass.h"
#include <set>
}
}
- // dominates - Return true if A dominates B. THis performs the
+ // dominates - Return true if A dominates B. This performs the
// special checks necessary if A and B are in the same basic block.
bool dominates(Instruction *A, Instruction *B);
return dominates(A, B) && A != B;
}
+ /// isReachableFromEntry - Return true if A is dominated by the entry
+ /// block of the function containing it.
+ bool isReachableFromEntry(BasicBlock* A) {
+ return dominates(&A->getParent()->getEntryBlock(), A);
+ }
+
/// Return the nearest common dominator of A and B.
BasicBlock *nearestCommonDominator(BasicBlock *A, BasicBlock *B) const {
ETNode *NodeA = getNode(A);
// Can we eliminate this phi node now?
if (Value *V = PN->hasConstantValue(true)) {
Instruction *I = dyn_cast<Instruction>(V);
+ // If I is in NewBB, the ETForest call will fail, because NewBB isn't
+ // registered in ETForest yet. Handle this case explicitly.
if (!I || (I->getParent() != NewBB &&
getAnalysis<ETForest>().dominates(I, PN))) {
PN->replaceAllUsesWith(V);
{
BasicBlock *OnePred = PredBlocks[0];
unsigned i = 1, e = PredBlocks.size();
- for (i = 1; !ETF.dominates(&OnePred->getParent()->getEntryBlock(), OnePred);
- ++i) {
+ for (i = 1; !ETF.isReachableFromEntry(OnePred); ++i) {
assert(i != e && "Didn't find reachable pred?");
OnePred = PredBlocks[i];
}
for (; i != e; ++i)
- if (PredBlocks[i] != OnePred &&
- ETF.dominates(&PredBlocks[i]->getParent()->getEntryBlock(), OnePred)){
+ if (PredBlocks[i] != OnePred && ETF.isReachableFromEntry(OnePred)){
NewBBDominatesNewBBSucc = false;
break;
}