[llvm] r246449 - Repress sanitization on User dtor. Modify msan macros for applying attribute

[Evgenii Stepanov via llvm-commits]

We have the options, and they are off by default at this point. But we
want to enable them on the sanitizer bootstrap bot sooner or later.


On Mon, Aug 31, 2015 at 12:26 PM, Naomi Musgrave <nmusgrave at google.com> wrote:
> I'm not entirely sure if the compile and runtime options for use-after-dtor
> poisoning will be fully integrated into MSan or not when I leave. To
> clarify, are you reccommending leaving these as distinct options?
>
> On Mon, Aug 31, 2015 at 12:22 PM, Eric Christopher <echristo at gmail.com>
> wrote:
>>
>>
>>
>> On Mon, Aug 31, 2015 at 10:36 AM Naomi Musgrave <nmusgrave at google.com>
>> wrote:
>>>
>>> I have looked repeatedly into a fix for this bug, with no progress yet.
>>> I'm currently repressing it to be able to proceed with investigating other
>>> bugs.
>>
>>
>> OK. That seems reasonable.
>>
>>>
>>> If I have not resolved this issue before my internship is over, I think
>>> it may be better to file bugs against these issues.
>>>
>>
>> *nod* Might be worth an option to disable the feature in general so we
>> don't need the source annotations?
>>
>> -eric
>>
>>>
>>> Note: commit reverted in rL246450 due to it breaking a flaky build.
>>>
>>> On Mon, Aug 31, 2015 at 9:23 AM, Eric Christopher <echristo at gmail.com>
>>> wrote:
>>>>
>>>>
>>>>>
>>>>> Summary: In response to bug 24578, reported against failing LLVM test.
>>>>>
>>>>
>>>> FWIW we generally just say "PR24578"
>>>>
>>>> So, hrm, how long do we expect the "workaround" annotation to be in the
>>>> source?
>>>>
>>>> -eric
>>>>
>>>>
>>>>>
>>>>> Reviewers: chandlerc, rsmith, eugenis
>>>>>
>>>>> Subscribers: llvm-commits
>>>>>
>>>>> Differential Revision: http://reviews.llvm.org/D12335
>>>>>
>>>>> Modified:
>>>>>     llvm/trunk/include/llvm/IR/User.h
>>>>>     llvm/trunk/include/llvm/Support/Compiler.h
>>>>>     llvm/trunk/lib/IR/Metadata.cpp
>>>>>     llvm/trunk/lib/IR/User.cpp
>>>>>
>>>>> Modified: llvm/trunk/include/llvm/IR/User.h
>>>>> URL:
>>>>> http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/User.h?rev=246449&r1=246448&r2=246449&view=diff
>>>>>
>>>>> ==============================================================================
>>>>> --- llvm/trunk/include/llvm/IR/User.h (original)
>>>>> +++ llvm/trunk/include/llvm/IR/User.h Mon Aug 31 10:57:40 2015
>>>>> @@ -72,8 +72,7 @@ protected:
>>>>>    void growHungoffUses(unsigned N, bool IsPhi = false);
>>>>>
>>>>>  public:
>>>>> -  ~User() override {
>>>>> -  }
>>>>> +  ~User() override {}
>>>>>    /// \brief Free memory allocated for User and Use objects.
>>>>>    void operator delete(void *Usr);
>>>>>    /// \brief Placement delete - required by std, but never called.
>>>>>
>>>>> Modified: llvm/trunk/include/llvm/Support/Compiler.h
>>>>> URL:
>>>>> http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/Compiler.h?rev=246449&r1=246448&r2=246449&view=diff
>>>>>
>>>>> ==============================================================================
>>>>> --- llvm/trunk/include/llvm/Support/Compiler.h (original)
>>>>> +++ llvm/trunk/include/llvm/Support/Compiler.h Mon Aug 31 10:57:40 2015
>>>>> @@ -323,10 +323,12 @@
>>>>>  #if __has_feature(memory_sanitizer)
>>>>>  # define LLVM_MEMORY_SANITIZER_BUILD 1
>>>>>  # include <sanitizer/msan_interface.h>
>>>>> +# define LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE
>>>>> __attribute__((no_sanitize_memory))
>>>>>  #else
>>>>>  # define LLVM_MEMORY_SANITIZER_BUILD 0
>>>>>  # define __msan_allocated_memory(p, size)
>>>>>  # define __msan_unpoison(p, size)
>>>>> +# define LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE
>>>>>  #endif
>>>>>
>>>>>  /// \macro LLVM_ADDRESS_SANITIZER_BUILD
>>>>>
>>>>> Modified: llvm/trunk/lib/IR/Metadata.cpp
>>>>> URL:
>>>>> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Metadata.cpp?rev=246449&r1=246448&r2=246449&view=diff
>>>>>
>>>>> ==============================================================================
>>>>> --- llvm/trunk/lib/IR/Metadata.cpp (original)
>>>>> +++ llvm/trunk/lib/IR/Metadata.cpp Mon Aug 31 10:57:40 2015
>>>>> @@ -401,7 +401,9 @@ void *MDNode::operator new(size_t Size,
>>>>>    return Ptr;
>>>>>  }
>>>>>
>>>>> -void MDNode::operator delete(void *Mem) {
>>>>> +// Repress memory sanitization, due to use-after-destroy by operator
>>>>> +// delete. Bug report 24578 identifies this issue.
>>>>> +LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE void MDNode::operator delete(void
>>>>> *Mem) {
>>>>>    MDNode *N = static_cast<MDNode *>(Mem);
>>>>>    size_t OpSize = N->NumOperands * sizeof(MDOperand);
>>>>>    OpSize = RoundUpToAlignment(OpSize, llvm::alignOf<uint64_t>());
>>>>>
>>>>> Modified: llvm/trunk/lib/IR/User.cpp
>>>>> URL:
>>>>> http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/User.cpp?rev=246449&r1=246448&r2=246449&view=diff
>>>>>
>>>>> ==============================================================================
>>>>> --- llvm/trunk/lib/IR/User.cpp (original)
>>>>> +++ llvm/trunk/lib/IR/User.cpp Mon Aug 31 10:57:40 2015
>>>>> @@ -118,7 +118,9 @@ void *User::operator new(size_t Size) {
>>>>>  //                         User operator delete Implementation
>>>>>
>>>>> //===----------------------------------------------------------------------===//
>>>>>
>>>>> -void User::operator delete(void *Usr) {
>>>>> +// Repress memory sanitization, due to use-after-destroy by operator
>>>>> +// delete. Bug report 24578 identifies this issue.
>>>>> +LLVM_NO_SANITIZE_MEMORY_ATTRIBUTE void User::operator delete(void
>>>>> *Usr) {
>>>>>    // Hung off uses use a single Use* before the User, while other
>>>>> subclasses
>>>>>    // use a Use[] allocated prior to the user.
>>>>>    User *Obj = static_cast<User *>(Usr);
>>>>>
>>>>>
>>>>> _______________________________________________
>>>>> llvm-commits mailing list
>>>>> llvm-commits at lists.llvm.org
>>>>> http://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-commits
>>>
>>>
>>>
>>>
>>> --
>>> - Naomi Musgrave
>>>
>
>
>
> --
> - Naomi Musgrave
>