This is the mail archive of the gcc-patches@gcc.gnu.org mailing list for the GCC project.

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]
Other format:	[Raw text]

Re: [PATCH: PR target/40697] Use shifts to extract most or least significant bits

From: Steven Bosscher <stevenb dot gcc at gmail dot com>
To: Carrot Wei <carrot at google dot com>
Cc: Paolo Bonzini <bonzini at gnu dot org>, gcc-patches at gcc dot gnu dot org
Date: Tue, 14 Jul 2009 10:26:06 +0200
Subject: Re: [PATCH: PR target/40697] Use shifts to extract most or least significant bits
References: <7587b290907131913g5d0f64fdi51767bb18bcf7371@mail.gmail.com> <4A5C19C4.9050501@gnu.org> <7587b290907140036v622d9f0av6f6b36bd63260544@mail.gmail.com>

On Tue, Jul 14, 2009 at 9:36 AM, Carrot Wei<carrot@google.com> wrote:
> ? ? ? ?PR target/40416
> ? ? ? ?* config/arm/arm.c (all_ones_in_most_significant_bits): New function.
> ? ? ? ?(all_ones_in_least_significant_bits): New function.
> ? ? ? ?* config/arm/arm-protos.h (all_ones_in_most_significant_bits):
> ? ? ? ? ? ? ? ?Declare it.
> ? ? ? ? ? ? ? ?(all_ones_in_least_significant_bits): Declare it.
> ? ? ? ?* config/arm/arm.md: Add peephole2 rules to do the optimization.

I still don't see why this can't be done in the middle-end instead of
as a peephole...

Ciao!
Steven

Follow-Ups:
- Re: [PATCH: PR target/40697] Use shifts to extract most or least significant bits
  - From: Adam Nemet

References:
- [PATCH: PR target/40697] Use shifts to extract most or least significant bits
  - From: Carrot Wei
- Re: [PATCH: PR target/40697] Use shifts to extract most or least significant bits
  - From: Paolo Bonzini
- Re: [PATCH: PR target/40697] Use shifts to extract most or least significant bits
  - From: Carrot Wei

Index Nav:	[Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav:	[Date Prev] [Date Next]	[Thread Prev] [Thread Next]