Re: SRA generates uninitialized var use

[Xinliang David Li <davidxl@google.com>]

It is used to indicate the fact the var decl needs to have a memory
home (addressable) -- is there another way to do this? this is to
avoid the following situation:

1) after SRA before update SSA, the IR looks like:

   MEM[.... &SR_123] = ...

   other_var = SR_123;   <---- (x)


In this case, SR_123 is not of aggregate type, and it is not
addressable, update_ssa won't assign a VUSE for (x), leading to

2) final IR after SRA:

   MEM[..., &SR_123] = ..
   other_var = SR_123_yyy(D);


David

On Mon, Jun 20, 2011 at 4:13 AM, Richard Guenther
<richard.guenther@gmail.com> wrote:
> On Sat, Jun 18, 2011 at 10:56 AM, Xinliang David Li <davidxl@google.com> wrote:
>> Compiling the test case in the patch with -O2 -m32 without the fix,
>> the program will abort. The problem is a var decl whose address is
>> taken is not marked as addressable leading to bad SSA update (missing
>> VUSE).  (the triaging used the the .after and .after_cleanup dump diff
>> and found the problem).
>>
>> the test is on going. Ok after testing?
>
> That doesn't make sense.  SRA shouldn't generate anything that has
> its address taken.  So, where do we take its address?
>
> Richard.
>
>> Thanks,
>>
>> David
>>
>