From e4f20af5c4dad10c85c0e6a5dc6aa2a1cb322ce9 Mon Sep 17 00:00:00 2001
From: Nick Lewycky <nicholas@mxc.ca>
Date: Sun, 24 Jun 2012 01:44:08 +0000
Subject: [PATCH] Remove a dangling reference to a deleted instruction. Fixes
 PR13185!

llvm-svn: 159096
---
 lib/Transforms/Scalar/Reassociate.cpp |  1 +
 test/Transforms/Reassociate/crash.ll  | 11 +++++++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/Transforms/Scalar/Reassociate.cpp b/lib/Transforms/Scalar/Reassociate.cpp
index 2b0d406c15d..b572f4eb077 100644
--- a/lib/Transforms/Scalar/Reassociate.cpp
+++ b/lib/Transforms/Scalar/Reassociate.cpp
@@ -1478,6 +1478,7 @@ void Reassociate::EraseInst(Instruction *I) {
   SmallVector<Value*, 8> Ops(I->op_begin(), I->op_end());
   // Erase the dead instruction.
   ValueRankMap.erase(I);
+  RedoInsts.remove(I);
   I->eraseFromParent();
   // Optimize its operands.
   SmallPtrSet<Instruction *, 8> Visited; // Detect self-referential nodes.
diff --git a/test/Transforms/Reassociate/crash.ll b/test/Transforms/Reassociate/crash.ll
index bbe4f233e82..e2ebcddf6b1 100644
--- a/test/Transforms/Reassociate/crash.ll
+++ b/test/Transforms/Reassociate/crash.ll
@@ -108,3 +108,14 @@ unreachable4:
   %z4 = add i32 %y4, %y4
   ret void
 }
+
+; PR13185
+define void @pr13185(i16 %p) {
+entry:
+  br label %for.cond
+
+for.cond:                                         ; preds = %for.cond, %entry
+  %x.0 = phi i32 [ undef, %entry ], [ %conv, %for.cond ]
+  %conv = zext i16 %p to i32
+  br label %for.cond
+}