On Thu, Jul 28, 2011 at 03:38:07PM +0800, Carrot Wei wrote:
> OK for trunk and 4.6?
>
> ChangeLog:
> 2011-07-28 Wei Guozhi <car...@google.com>
>
> PR rtl-optimization/49799
> * combine.c (make_compound_operation): Check if the bit field is valid
> before change it to bit field extraction.
Looks good to me, handling SHIFT_COUNT_TRUNCATED here isn't IMHO necessary
and the checking whether shift count is in the right range matches other rtx
simplifications (e.g. in simplify-rtx.c).
Though, you should add a testcase, probably
/* PR rtl-optimization/49799 */
/* { dg-do assemble } */
/* { dg-options "-O2 -w" } */
plus not sure if for arm you don't want to force this -march=armv7-a
into dg-options too or just leave it as is.
Jakub
