fix PR8102, a case where we'd copyValue from a value that we already

deleted.  Fix this by doing the copyValue's before we delete stuff!

The testcase only repros the problem on my system with valgrind.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@113820 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 11 insertions, 11 deletions

diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp
index 0db7ba7..af9a7ee 100644
--- a/lib/Transforms/Scalar/LICM.cpp
+++ b/lib/Transforms/Scalar/LICM.cpp
@@ -837,6 +837,17 @@ void LICM::PromoteAliasSet(AliasSet &AS) {
     ReplacedLoads[ALoad] = NewVal;
   }
   
+  // If the preheader load is itself a pointer, we need to tell alias analysis
+  // about the new pointer we created in the preheader block and about any PHI
+  // nodes that just got inserted.
+  if (PreheaderLoad->getType()->isPointerTy()) {
+    // Copy any value stored to or loaded from a must-alias of the pointer.
+    CurAST->copyValue(SomeValue, PreheaderLoad);
+    
+    for (unsigned i = 0, e = NewPHIs.size(); i != e; ++i)
+      CurAST->copyValue(SomeValue, NewPHIs[i]);
+  }
+  
   // Now that everything is rewritten, delete the old instructions from the body
   // of the loop.  They should all be dead now.
   for (unsigned i = 0, e = LoopUses.size(); i != e; ++i) {
@@ -867,17 +878,6 @@ void LICM::PromoteAliasSet(AliasSet &AS) {
     User->eraseFromParent();
   }
   
-  // If the preheader load is itself a pointer, we need to tell alias analysis
-  // about the new pointer we created in the preheader block and about any PHI
-  // nodes that just got inserted.
-  if (PreheaderLoad->getType()->isPointerTy()) {
-    // Copy any value stored to or loaded from a must-alias of the pointer.
-    CurAST->copyValue(SomeValue, PreheaderLoad);
-
-    for (unsigned i = 0, e = NewPHIs.size(); i != e; ++i)
-      CurAST->copyValue(SomeValue, NewPHIs[i]);
-  }
-  
   // fwew, we're done!
 }