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From: Paul Brook <paul@codesourcery.com>
To: gcc@gcc.gnu.org
Cc: DJ Delorie <dj@redhat.com>,  wilson@specifix.com
Subject: Re: hard_regno_nregs == 0 ?
Date: Wed, 09 Jan 2008 21:48:00 -0000	[thread overview]
Message-ID: <200801092147.55675.paul@codesourcery.com> (raw)
In-Reply-To: <200801092038.m09KcckZ026515@greed.delorie.com>

>  @defmac HARD_REGNO_NREGS (@var{regno}, @var{mode})
>  A C expression for the number of consecutive hard registers, starting
>  at register number @var{regno}, required to hold a value of mode
> -@var{mode}.
> +@var{mode}.  This macro must never return zero, even if a register
> +cannot hold the requested mode - indicate that with HARD_REGNO_MODE_OK
> +and/or CANNOT_CHANGE_MODE_CLASS instead.

I find this somewhat unclear - It seems to imply that HARD_REGNO_NREGS may be 
called even when HARD_REGNO_MODE_OK returns false.

How about:

This macro must return a nonzero value for all combinations permitted by 
HARD_REGNO_MODE_OK and CANNOT_CHANGE_MODE_CLASS.

Paul

  reply	other threads:[~2008-01-09 21:48 UTC|newest]

Thread overview: 13+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2008-01-08 20:13 DJ Delorie
2008-01-09 16:43 ` Ian Lance Taylor
2008-01-09 16:47   ` DJ Delorie
2008-01-09 16:56     ` Ian Lance Taylor
2008-01-09 20:18     ` Jim Wilson
2008-01-09 19:27 ` Jim Wilson
2008-01-09 20:39   ` DJ Delorie
2008-01-09 21:48     ` Paul Brook [this message]
2008-01-09 22:02       ` DJ Delorie
2008-01-11  0:12     ` Jim Wilson
2008-01-11  0:16       ` DJ Delorie
2008-01-12  0:48         ` Jim Wilson
2008-01-21 22:41           ` DJ Delorie

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