llvm dev - Jun 2010 - [LLVMdev] Why google-perftools fails on the JITted code?

On Jun 18, 2010, at 3:29 AM, Yuri wrote:
> Now I see that JITted code doesn't have standard prolog, on x86 each 
> procedure instead begins with 'sub    $0x4,%esp'.
> 
> Is there an option to make JIT generate regular prologs?
Try turning off frame pointer elimination.  On the llc command line, this is
-disable-fp-elim

-Chris

> 
> Yuri
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On Sat, Jun 19, 2010 at 4:35 AM, Chris Lattner <clattner at apple.com>
wrote:
>
> On Jun 18, 2010, at 3:29 AM, Yuri wrote:
>
>> Now I see that JITted code doesn't have standard prolog, on x86
each
>> procedure instead begins with 'sub    $0x4,%esp'.
>>
>> Is there an option to make JIT generate regular prologs?
>
> Try turning off frame pointer elimination.  On the llc command line, this
is -disable-fp-elim
>
What does llc have to do with the JIT?

On Jun 19, 2010, at 6:57 AM, Paul Davey wrote:
> On Sat, Jun 19, 2010 at 4:35 AM, Chris Lattner <clattner at
apple.com> wrote:
>> 
>> On Jun 18, 2010, at 3:29 AM, Yuri wrote:
>> 
>>> Now I see that JITted code doesn't have standard prolog, on x86
each
>>> procedure instead begins with 'sub    $0x4,%esp'.
>>> 
>>> Is there an option to make JIT generate regular prologs?
>> 
>> Try turning off frame pointer elimination.  On the llc command line,
this is -disable-fp-elim
>> 
> 
> What does llc have to do with the JIT?
llc and lli use the same code generator.  LLI takes the -disable-fp-elim flag
also.  If you have embedded this JIT in your own stuff (which wasn't
specified) you need to use the same api that the -disable-fp-elim flag sets in
these two tools.

-Chris

On 06/19/2010 06:57, Paul Davey wrote:
> What does llc have to do with the JIT?
>    
I think he meant lli.
Actually I use API instead and setting the flag equivalent to this 
option worked. Now google-perftools generates the correct profile.

Yuri