Autotuning parameters/heuristics within gcc - best place to start?

[Robert Stevenson]

Hi,

I am planning to begin a project to explore the space of tuning gcc
internals in an effort to increase performance. I am wondering if
anyone can point to me any parameterizations, heuristics, or
priorities functions within gcc that can be tuned/adjusted. Some
general areas I am considering include register allocation and data
prefetching.

Thanks,
Robert

Using add_stmt in gimplify.c

[Robert Stevenson]

Hello Everyone,
 I am trying to add some information/instructions into loop statements in 
GCC front-end. For this, in the previous gcc, I have used "add_stmt" to insert 
these instructions and they worked fine. When I do it in gcc 4.6 (snapshot 
2010/12/4) I get "undefined references to "add_stmt."

One thing I found different in this 4.6 version of gcc is that the files 
prefixed with "c-" have been stored in the c-family director. Is this the 
reason 
why I am not able to use add_stmt in the gimplify.c function? What can I do to 
use "add_stmt" function?


Any form of help is truly appreciated!

I have not subscribed to gcc mailing list, so please copy me when you reply.

Regards,

Bobby.


  

Re: Using add_stmt in gimplify.c

[Robert Stevenson]

Is there any change I should do to the Makefile.in or any other files? Is there 
any specific header files I should add ? (I have c-family/c-common.h). 


Regards,

Bobby




- Original Message 
From: Ian Lance Taylor 
To: Robert Stevenson 
Cc: g...@gnu.org
Sent: Wed, December 15, 2010 11:19:44 PM
Subject: Re: Using add_stmt in gimplify.c

Robert Stevenson  writes:

>  I am trying to add some information/instructions into loop statements in 
> GCC front-end. For this, in the previous gcc, I have used "add_stmt" to 
> insert 

> these instructions and they worked fine. When I do it in gcc 4.6 (snapshot 
> 2010/12/4) I get "undefined references to "add_stmt."
>
> One thing I found different in this 4.6 version of gcc is that the files 
> prefixed with "c-" have been stored in the c-family director. Is this the 
>reason 
>
> why I am not able to use add_stmt in the gimplify.c function? What can I do 
> to 

> use "add_stmt" function?

add_stmt is still there in the C and C++ frontends; I don't know why it
doesn't work for you.  But you shouldn't really call it from gimplify.c
anyhow, as add_stmt adds statements to the wrong place.  In gimplify.c
you should use functions like gimplify_seq_add_stmt.  There are many
examples in that file.

Ian