[cfe-commits] r157204 - in /cfe/trunk: lib/StaticAnalyzer/Core/ObjCMessage.cpp test/Analysis/PR12905.c

[Anna Zaks]

On May 21, 2012, at 1:36 PM, Benjamin Kramer wrote:

> 
> On 21.05.2012, at 22:04, Anna Zaks wrote:
> 
>> Benjamin,
>> 
>> The issue is that the size of the string is 1, correct? Can we just check the size and return if it's less than 2 and proceed with the existing checks afterwards? This function is called a lot.
> 
> LLVM knows how to generate great optimized code for startswith, it becomes a check that the length is >=2 and two unaligned loads + compares. It's far more readable and I doubt that it's slower than the old buggy code.
> 
>> Do you have a test case?
> 
> Yes, and a reduced version was committed along with this fix.
> 
Sorry, I've missed that.
> - Ben
> 
>> 
>> Thanks,
>> Anna.
>> On May 21, 2012, at 12:40 PM, Benjamin Kramer wrote:
>> 
>>> Author: d0k
>>> Date: Mon May 21 14:40:38 2012
>>> New Revision: 157204
>>> 
>>> URL: http://llvm.org/viewvc/llvm-project?rev=157204&view=rev
>>> Log:
>>> Analyzer: Fix PR12905, a crash when encountering a call to a function named "C".
>>> 
>>> While there clean up indentation.
>>> 
>>> Added:
>>>  cfe/trunk/test/Analysis/PR12905.c
>>> Modified:
>>>  cfe/trunk/lib/StaticAnalyzer/Core/ObjCMessage.cpp
>>> 
>>> Modified: cfe/trunk/lib/StaticAnalyzer/Core/ObjCMessage.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/StaticAnalyzer/Core/ObjCMessage.cpp?rev=157204&r1=157203&r2=157204&view=diff
>>> ==============================================================================
>>> --- cfe/trunk/lib/StaticAnalyzer/Core/ObjCMessage.cpp (original)
>>> +++ cfe/trunk/lib/StaticAnalyzer/Core/ObjCMessage.cpp Mon May 21 14:40:38 2012
>>> @@ -161,16 +161,15 @@
>>> }
>>> 
>>> bool CallOrObjCMessage::isCFCGAllowingEscape(StringRef FName) {
>>> -  if (FName[0] == 'C' && (FName[1] == 'F' || FName[1] == 'G'))
>>> -         if (StrInStrNoCase(FName, "InsertValue") != StringRef::npos||
>>> -             StrInStrNoCase(FName, "AddValue") != StringRef::npos ||
>>> -             StrInStrNoCase(FName, "SetValue") != StringRef::npos ||
>>> -             StrInStrNoCase(FName, "WithData") != StringRef::npos ||
>>> -             StrInStrNoCase(FName, "AppendValue") != StringRef::npos||
>>> -             StrInStrNoCase(FName, "SetAttribute") != StringRef::npos) {
>>> -       return true;
>>> -     }
>>> -  return false;
>>> +  if (!FName.startswith("CF") && !FName.startswith("CG"))
>>> +    return false;
>>> +
>>> +  return StrInStrNoCase(FName, "InsertValue")  != StringRef::npos ||
>>> +         StrInStrNoCase(FName, "AddValue")     != StringRef::npos ||
>>> +         StrInStrNoCase(FName, "SetValue")     != StringRef::npos ||
>>> +         StrInStrNoCase(FName, "WithData")     != StringRef::npos ||
>>> +         StrInStrNoCase(FName, "AppendValue")  != StringRef::npos ||
>>> +         StrInStrNoCase(FName, "SetAttribute") != StringRef::npos;
>>> }
>>> 
>>> 
>>> 
>>> Added: cfe/trunk/test/Analysis/PR12905.c
>>> URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Analysis/PR12905.c?rev=157204&view=auto
>>> ==============================================================================
>>> --- cfe/trunk/test/Analysis/PR12905.c (added)
>>> +++ cfe/trunk/test/Analysis/PR12905.c Mon May 21 14:40:38 2012
>>> @@ -0,0 +1,8 @@
>>> +// RUN: %clang_cc1 -analyze -analyzer-checker=core %s
>>> +// PR12905
>>> +
>>> +void C(void);
>>> +
>>> +void t(void) {
>>> +  C();
>>> +}
>>> 
>>> 
>>> _______________________________________________
>>> cfe-commits mailing list
>>> cfe-commits at cs.uiuc.edu
>>> http://lists.cs.uiuc.edu/mailman/listinfo/cfe-commits
>> 
>