Cleanup some from my DomSet-removal changes. Add a new

isReachableFromEntry
test to ETForest to factor a common test out of code.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@35786 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Owen Anderson 2007-04-09 00:52:49 +00:00
parent d2eae62e93
commit 558fc740da
2 changed files with 12 additions and 5 deletions

View File

@ -27,6 +27,7 @@
#define LLVM_ANALYSIS_DOMINATORS_H
#include "llvm/Analysis/ET-Forest.h"
#include "llvm/Function.h"
#include "llvm/Pass.h"
#include <set>
@ -395,7 +396,7 @@ public:
}
}
// 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);
@ -405,6 +406,12 @@ public:
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);

View File

@ -312,6 +312,8 @@ BasicBlock *LoopSimplify::SplitBlockPredecessors(BasicBlock *BB,
// 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);
@ -701,15 +703,13 @@ void LoopSimplify::UpdateDomInfoForRevectoredPreds(BasicBlock *NewBB,
{
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;
}