[llvm] r310373 - BasicAA: aliasGEP shouldn't get a PartialAlias response here

[Nuno Lopes via llvm-commits]

Author: nlopes
Date: Tue Aug  8 09:13:24 2017
New Revision: 310373

URL: http://llvm.org/viewvc/llvm-project?rev=310373&view=rev
Log:
BasicAA: aliasGEP shouldn't get a PartialAlias response here
add an assert() to ensure that's the case (as I'm not convinced it won't happen)

Modified:
    llvm/trunk/lib/Analysis/BasicAliasAnalysis.cpp

Modified: llvm/trunk/lib/Analysis/BasicAliasAnalysis.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/BasicAliasAnalysis.cpp?rev=310373&r1=310372&r2=310373&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/BasicAliasAnalysis.cpp (original)
+++ llvm/trunk/lib/Analysis/BasicAliasAnalysis.cpp Tue Aug  8 09:13:24 2017
@@ -1196,8 +1196,10 @@ AliasResult BasicAAResult::aliasGEP(cons
 
     // If we get a No or May, then return it immediately, no amount of analysis
     // will improve this situation.
-    if (BaseAlias != MustAlias)
+    if (BaseAlias != MustAlias) {
+      assert(BaseAlias == NoAlias || BaseAlias == MayAlias);
       return BaseAlias;
+    }
 
     // Otherwise, we have a MustAlias.  Since the base pointers alias each other
     // exactly, see if the computed offset from the common pointer tells us