Fix PR1487 and Transforms/IndVar/2007-06-06-DeleteDanglesPtr.ll
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@37459 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/ScalarEvolution.cpp b/lib/Analysis/ScalarEvolution.cpp
index 1ff21a7..b1c3a17 100644
--- a/lib/Analysis/ScalarEvolution.cpp
+++ b/lib/Analysis/ScalarEvolution.cpp
@@ -1196,9 +1196,28 @@
/// client before it removes an instruction from the program, to make sure
/// that no dangling references are left around.
void ScalarEvolutionsImpl::deleteInstructionFromRecords(Instruction *I) {
- Scalars.erase(I);
- if (PHINode *PN = dyn_cast<PHINode>(I))
- ConstantEvolutionLoopExitValue.erase(PN);
+ SmallVector<Instruction *, 16> Worklist;
+
+ if (Scalars.erase(I)) {
+ if (PHINode *PN = dyn_cast<PHINode>(I))
+ ConstantEvolutionLoopExitValue.erase(PN);
+ Worklist.push_back(I);
+ }
+
+ while (!Worklist.empty()) {
+ Instruction *II = Worklist.back();
+ Worklist.pop_back();
+
+ for (Instruction::use_iterator UI = II->use_begin(), UE = II->use_end();
+ UI != UE; ++UI) {
+ Instruction *Inst = dyn_cast<Instruction>(*UI);
+ if (Inst && hasSCEV(Inst) && Scalars.erase(Inst)) {
+ if (PHINode *PN = dyn_cast<PHINode>(II))
+ ConstantEvolutionLoopExitValue.erase(PN);
+ Worklist.push_back(Inst);
+ }
+ }
+ }
}