The rewriter may hold references to instructions that are deleted because they are trivially dead.
Fix by clearing the rewriter cache before deleting the trivially dead
instructions.
Also make InsertedExpressions use an AssertingVH to catch these
bugs easier.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@72364 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolutionExpander.cpp b/lib/Analysis/ScalarEvolutionExpander.cpp
index 507ced7..fc66ddb 100644
--- a/lib/Analysis/ScalarEvolutionExpander.cpp
+++ b/lib/Analysis/ScalarEvolutionExpander.cpp
@@ -526,7 +526,7 @@
Value *SCEVExpander::expand(const SCEV *S) {
// Check to see if we already expanded this.
- std::map<SCEVHandle, Value*>::iterator I = InsertedExpressions.find(S);
+ std::map<SCEVHandle, AssertingVH<Value> >::iterator I = InsertedExpressions.find(S);
if (I != InsertedExpressions.end())
return I->second;
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp
index 89742c5..6704990 100644
--- a/lib/Transforms/Scalar/IndVarSimplify.cpp
+++ b/lib/Transforms/Scalar/IndVarSimplify.cpp
@@ -298,6 +298,7 @@
// in the loop, so we don't need an LCSSA phi node anymore.
if (NumPreds == 1) {
PN->replaceAllUsesWith(ExitVal);
+ Rewriter.clear();
RecursivelyDeleteTriviallyDeadInstructions(PN);
break;
}
@@ -418,6 +419,7 @@
// Reorder instructions to avoid use-before-def conditions.
FixUsesBeforeDefs(L, Rewriter);
+ Rewriter.clear();
// For completeness, inform IVUsers of the IV use in the newly-created
// loop exit test instruction.
if (NewICmp)