[llvm] r222997 - [msan] Add compile-time checks for missing origins.

[Evgeniy Stepanov]

On Mon, Dec 1, 2014 at 8:06 PM, Sergey Matveev <earthdok at google.com> wrote:
> NFC? Can't this potentially cause new compilation failures?

Well, yes, if I made a mistake somewhere.
No functional change intended is what I meant.


> On Mon, Dec 1, 2014 at 12:53 PM, Evgeniy Stepanov
> <eugeni.stepanov at gmail.com> wrote:
>>
>> Author: eugenis
>> Date: Mon Dec  1 03:53:51 2014
>> New Revision: 222997
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=222997&view=rev
>> Log:
>> [msan] Add compile-time checks for missing origins.
>>
>> This change makes MemorySanitizer instrumentation a bit more strict
>> about instructions that have no origin id assigned to them.
>>
>> This would have caught the bug that was fixed in r222918.
>>
>> No functional change.
>>
>> Modified:
>>     llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
>>
>> Modified: llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
>> URL:
>> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp?rev=222997&r1=222996&r2=222997&view=diff
>>
>> ==============================================================================
>> --- llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp
>> (original)
>> +++ llvm/trunk/lib/Transforms/Instrumentation/MemorySanitizer.cpp Mon Dec
>> 1 03:53:51 2014
>> @@ -921,6 +921,8 @@ struct MemorySanitizerVisitor : public I
>>              Value *OriginPtr =
>>                  getOriginPtrForArgument(&FArg, EntryIRB, ArgOffset);
>>              setOrigin(A, EntryIRB.CreateLoad(OriginPtr));
>> +          } else {
>> +            setOrigin(A, getCleanOrigin());
>>            }
>>          }
>>          ArgOffset += RoundUpToAlignment(Size, kShadowTLSAlignment);
>> @@ -940,15 +942,13 @@ struct MemorySanitizerVisitor : public I
>>    /// \brief Get the origin for a value.
>>    Value *getOrigin(Value *V) {
>>      if (!MS.TrackOrigins) return nullptr;
>> -    if (isa<Instruction>(V) || isa<Argument>(V)) {
>> -      Value *Origin = OriginMap[V];
>> -      if (!Origin) {
>> -        DEBUG(dbgs() << "NO ORIGIN: " << *V << "\n");
>> -        Origin = getCleanOrigin();
>> -      }
>> -      return Origin;
>> -    }
>> -    return getCleanOrigin();
>> +    if (!PropagateShadow) return getCleanOrigin();
>> +    if (isa<Constant>(V)) return getCleanOrigin();
>> +    assert((isa<Instruction>(V) || isa<Argument>(V)) &&
>> +           "Unexpected value type in getOrigin()");
>> +    Value *Origin = OriginMap[V];
>> +    assert(Origin && "Missing origin");
>> +    return Origin;
>>    }
>>
>>    /// \brief Get the origin for i-th argument of the instruction I.
>> @@ -1088,6 +1088,7 @@ struct MemorySanitizerVisitor : public I
>>      IRB.CreateStore(getCleanShadow(&I), ShadowPtr);
>>
>>      setShadow(&I, getCleanShadow(&I));
>> +    setOrigin(&I, getCleanOrigin());
>>    }
>>
>>    void visitAtomicRMWInst(AtomicRMWInst &I) {
>>
>>
>> _______________________________________________
>> llvm-commits mailing list
>> llvm-commits at cs.uiuc.edu
>> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
>
>