Add a verifyAnalysis to LoopInfo, LoopSimplify, and LCSSA form that verify
that these passes are properly preserved.
Fix several transformation passes that claimed to preserve LoopSimplify
form but weren't.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@80926 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Utils/LoopSimplify.cpp b/lib/Transforms/Utils/LoopSimplify.cpp
index 56e5a46..36709f7 100644
--- a/lib/Transforms/Utils/LoopSimplify.cpp
+++ b/lib/Transforms/Utils/LoopSimplify.cpp
@@ -69,8 +69,8 @@
virtual void getAnalysisUsage(AnalysisUsage &AU) const {
// We need loop information to identify the loops...
- AU.addRequired<LoopInfo>();
- AU.addRequired<DominatorTree>();
+ AU.addRequiredTransitive<LoopInfo>();
+ AU.addRequiredTransitive<DominatorTree>();
AU.addPreserved<LoopInfo>();
AU.addPreserved<DominatorTree>();
@@ -83,9 +83,13 @@
void verifyAnalysis() const {
#ifndef NDEBUG
LoopInfo *NLI = &getAnalysis<LoopInfo>();
- for (LoopInfo::iterator I = NLI->begin(), E = NLI->end(); I != E; ++I)
+ for (LoopInfo::iterator I = NLI->begin(), E = NLI->end(); I != E; ++I) {
+ // Sanity check: Check basic loop invariants.
(*I)->verifyLoop();
-#endif
+ // Check the special guarantees that LoopSimplify makes.
+ assert((*I)->isLoopSimplifyForm());
+ }
+#endif
}
private:
@@ -346,15 +350,6 @@
BasicBlock *NewBB =
SplitBlockPredecessors(Header, &OutsideBlocks[0], OutsideBlocks.size(),
".preheader", this);
-
-
- //===--------------------------------------------------------------------===//
- // Update analysis results now that we have performed the transformation
- //
-
- // We know that we have loop information to update... update it now.
- if (Loop *Parent = L->getParentLoop())
- Parent->addBasicBlockToLoop(NewBB, LI->getBase());
// Make sure that NewBB is put someplace intelligent, which doesn't mess up
// code layout too horribly.
@@ -377,17 +372,6 @@
LoopBlocks.size(), ".loopexit",
this);
- // Update Loop Information - we know that the new block will be in whichever
- // loop the Exit block is in. Note that it may not be in that immediate loop,
- // if the successor is some other loop header. In that case, we continue
- // walking up the loop tree to find a loop that contains both the successor
- // block and the predecessor block.
- Loop *SuccLoop = LI->getLoopFor(Exit);
- while (SuccLoop && !SuccLoop->contains(L->getHeader()))
- SuccLoop = SuccLoop->getParentLoop();
- if (SuccLoop)
- SuccLoop->addBasicBlockToLoop(NewBB, LI->getBase());
-
return NewBB;
}
@@ -521,10 +505,6 @@
else
LI->changeTopLevelLoop(L, NewOuter);
- // This block is going to be our new header block: add it to this loop and all
- // parent loops.
- NewOuter->addBasicBlockToLoop(NewBB, LI->getBase());
-
// L is now a subloop of our outer loop.
NewOuter->addChildLoop(L);
@@ -532,6 +512,10 @@
I != E; ++I)
NewOuter->addBlockEntry(*I);
+ // Now reset the header in L, which had been moved by
+ // SplitBlockPredecessors for the outer loop.
+ L->moveToHeader(Header);
+
// Determine which blocks should stay in L and which should be moved out to
// the Outer loop now.
std::set<BasicBlock*> BlocksInL;