From mboxrd@z Thu Jan  1 00:00:00 1970
From: Dibyendu Majumdar <mobile@majumdar.org.uk>
Subject: Re: sparse-llvm incorrect definition of local variables
Date: Tue, 7 Mar 2017 07:31:34 +0000
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To: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Cc: Linux-Sparse <linux-sparse@vger.kernel.org>

Hi Luc,

On 7 March 2017 at 06:44, Luc Van Oostenryck
<luc.vanoostenryck@gmail.com> wrote:
> On Tue, Mar 07, 2017 at 12:08:22AM +0000, Dibyendu Majumdar wrote:
>> When I try to compile following in sparse-llvm:
>>
>> int main(const char *argv[]) {
>>  int values[5];
>>  values[0] = 9;
>>  ...
>>  values[4] = 5;
>>  int *p = &values[4];
>>  return (*p == 5) ? 0 : 1;
>> }
>>
>> I get:
>>
>> @values = external global [5 x i32]
>> ...
>>
>> Here 'values' has been defined above as external global, whereas it
>> should be allocated on the stack.
>
> Mmmh, I'll need to look a bit further at this one.
>

It appears that sparse-llvm only creates a local stack object for each
OP_PHI instruction. What should be the general approach for
identifying local stack objects in sparse linearized output?

Regards
Dibyendu