From: Duncan Sands <baldrick@free.fr>
Date: Thu, 11 Sep 2008 19:35:55 +0000 (+0000)
Subject: Intrinsics don't touch internal global variables
X-Git-Url: http://demsky.eecs.uci.edu/git/?a=commitdiff_plain;h=892b84007c980e58181cd94fea7d70c5ed9642c8;p=oota-llvm.git

Intrinsics don't touch internal global variables
(unless passed one via a parameter), even if they
are IntrWriteMem.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@56115 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/lib/Analysis/IPA/GlobalsModRef.cpp b/lib/Analysis/IPA/GlobalsModRef.cpp
index 6063a1d16b7..6736e6f3ce4 100644
--- a/lib/Analysis/IPA/GlobalsModRef.cpp
+++ b/lib/Analysis/IPA/GlobalsModRef.cpp
@@ -392,8 +392,10 @@ void GlobalsModRef::AnalyzeCallGraph(CallGraph &CG, Module &M) {
               FR.GlobalInfo[*GI] |= Ref;
           }
         } else {
-          // Can't say anything useful.
-          KnowNothing = true;
+          FunctionEffect |= ModRef;
+          // Can't say anything useful unless it's an intrinsic - they don't
+          // read or write global variables of the kind considered here.
+          KnowNothing = !F->isIntrinsic();
         }
         continue;
       }