From 8dff60e96a0b3044628511b0e43a59788de56b9d Mon Sep 17 00:00:00 2001 From: Nadav Rotem Date: Mon, 13 Aug 2012 23:03:43 +0000 Subject: MemoryDependenceAnalysis attempts to find the first memory dependency for function calls. Currently, if GetLocation reports that it did not find a valid pointer (this is the case for volatile load/stores), we ignore the result. This patch adds code to handle the cases where we did not obtain a valid pointer. rdar://11872864 PR12899 git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@161802 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Analysis/MemoryDependenceAnalysis.cpp | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) (limited to 'lib/Analysis/MemoryDependenceAnalysis.cpp') diff --git a/lib/Analysis/MemoryDependenceAnalysis.cpp b/lib/Analysis/MemoryDependenceAnalysis.cpp index 7fb154d68a..059e57493b 100644 --- a/lib/Analysis/MemoryDependenceAnalysis.cpp +++ b/lib/Analysis/MemoryDependenceAnalysis.cpp @@ -227,13 +227,18 @@ getCallSiteDependencyFrom(CallSite CS, bool isReadOnlyCall, // Otherwise if the two calls don't interact (e.g. InstCS is readnone) // keep scanning. - break; + continue; default: return MemDepResult::getClobber(Inst); } } + + // If we could not obtain a pointer for the instruction and the instruction + // touches memory then assume that this is a dependency. + if (MR != AliasAnalysis::NoModRef) + return MemDepResult::getClobber(Inst); } - + // No dependence found. If this is the entry block of the function, it is // unknown, otherwise it is non-local. if (BB != &BB->getParent()->getEntryBlock()) -- cgit v1.2.3