[LLVMdev] JIT allocates global data in function body memory

[Evan Cheng]

On Jul 2, 2009, at 5:20 PM, Reid Kleckner wrote:

> On Thu, Jul 2, 2009 at 3:09 PM, Evan Cheng<evan.cheng at apple.com>  
> wrote:
>> The patch looks good to me. But we cannot allow AllocateGVsWithCode  
>> to
>> be initialized to be false yet. Can you add a mechanism to define the
>> behavior when the JIT is created / initialized?
>
> That makes four optional arguments to ExecutionEngine::create.  Do you
> mind if I go ahead and add an EngineBuilder?

Please, thanks.

>
>> Also, I am not crazy about this being moved to JITMemoryManager.h.
>> This seems like implementation detail that should be kept hidden.
>>
>> +  // If the PoisonMemory parameter is true, freed memory should be
>> overwritten
>> +  // with garbage.  This parameter is useful for testing and  
>> debugging.
>> +#ifdef NDEBUG
>> +#define POISON true
>> +#else
>> +#define POISON false
>> +#endif
>
> I wasn't crazy about it either, but it was hard to construct a
> unittest that fails properly under release mode without it.  It also
> seems like it would be a useful feature for writing unit tests for
> other custom memory managers.  I can either axe it and let the test
> only do proper testing in debug mode, or I could add a
> setPoisonMemory(bool poison) method to the JITMemoryManager interface.
> Which would you prefer?

My preference would be to add a method to JITMemoryManager.

Thanks,

Evan

>
> Reid
>
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