Commit 0add565e authored by Hans Wennborg's avatar Hans Wennborg
Browse files

Merging r228444: 

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r228444 | eugenis | 2015-02-06 13:47:39 -0800 (Fri, 06 Feb 2015) | 8 lines

[msan] Fix "missing origin" in atomic store.

An atomic store always make the target location fully initialized (in the
current implementation). It should not store origin. Initialized memory can't
have meaningful origin, and, due to origin granularity (4 bytes) there is a
chance that this extra store would overwrite meaningfull origin for an adjacent
location.

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llvm-svn: 228445
parent 7e828334

llvm/lib/Transforms/Instrumentation/MemorySanitizer.cpp

+1 −1
Original line number Diff line number Diff line
@@ -631,7 +631,7 @@ struct MemorySanitizerVisitor : public InstVisitor<MemorySanitizerVisitor> { 


      if (SI.isAtomic()) SI.setOrdering(addReleaseOrdering(SI.getOrdering()));



      if (MS.TrackOrigins)

      if (MS.TrackOrigins && !SI.isAtomic())

        storeOrigin(IRB, Addr, Shadow, getOrigin(Val), SI.getAlignment(),

                    InstrumentWithCalls);

    }

llvm/test/Instrumentation/MemorySanitizer/atomics.ll

+2 −0
Original line number Diff line number Diff line 
; RUN: opt < %s -msan -msan-check-access-address=0 -S | FileCheck %s

; RUN: opt < %s -msan -msan-check-access-address=0 -msan-track-origins=1 -S | FileCheck %s

; RUN: opt < %s -msan -msan-check-access-address=0 -msan-track-origins=2 -S | FileCheck %s



target datalayout = "e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64-S128"

target triple = "x86_64-unknown-linux-gnu"