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.

llvm-svn: 80926

1 files changed, 16 insertions, 3 deletions

diff --git a/llvm/lib/Transforms/Utils/LCSSA.cpp b/llvm/lib/Transforms/Utils/LCSSA.cpp
index 84fcc64..e0251f8 100644
--- a/llvm/lib/Transforms/Utils/LCSSA.cpp
+++ b/llvm/lib/Transforms/Utils/LCSSA.cpp
@@ -58,6 +58,7 @@ namespace {
     DominatorTree *DT;
     std::vector<BasicBlock*> LoopBlocks;
     PredIteratorCache PredCache;
+    Loop *L;
     
     virtual bool runOnLoop(Loop *L, LPPassManager &LPM);
 
@@ -72,9 +73,9 @@ namespace {
       AU.setPreservesCFG();
       AU.addRequiredID(LoopSimplifyID);
       AU.addPreservedID(LoopSimplifyID);
-      AU.addRequired<LoopInfo>();
+      AU.addRequiredTransitive<LoopInfo>();
       AU.addPreserved<LoopInfo>();
-      AU.addRequired<DominatorTree>();
+      AU.addRequiredTransitive<DominatorTree>();
       AU.addPreserved<ScalarEvolution>();
       AU.addPreserved<DominatorTree>();
 
@@ -86,6 +87,17 @@ namespace {
       AU.addPreserved<DominanceFrontier>();
     }
   private:
+
+    /// verifyAnalysis() - Verify loop nest.
+    virtual void verifyAnalysis() const {
+#ifndef NDEBUG
+      // Sanity check: Check basic loop invariants.
+      L->verifyLoop();
+      // Check the special guarantees that LCSSA makes.
+      assert(L->isLCSSAForm());
+#endif
+    }
+
     void getLoopValuesUsedOutsideLoop(Loop *L,
                                       SetVector<Instruction*> &AffectedValues,
                                  const SmallVector<BasicBlock*, 8>& exitBlocks);
@@ -107,7 +119,8 @@ Pass *llvm::createLCSSAPass() { return new LCSSA(); }
 const PassInfo *const llvm::LCSSAID = &X;
 
 /// runOnFunction - Process all loops in the function, inner-most out.
-bool LCSSA::runOnLoop(Loop *L, LPPassManager &LPM) {
+bool LCSSA::runOnLoop(Loop *l, LPPassManager &LPM) {
+  L = l;
   PredCache.clear();
   
   LI = &LPM.getAnalysis<LoopInfo>();