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Re: multi-word operations
- To: David Edelsohn <dje at watson dot ibm dot com>, Richard Henderson <rth at cygnus dot com>
- Subject: Re: multi-word operations
- From: Richard Henderson <rth at cygnus dot com>
- Date: Fri, 14 Aug 1998 12:51:13 -0700
- Cc: egcs at cygnus dot com
- References: <9808141942.AA28480@marc.watson.ibm.com>
- Reply-To: Richard Henderson <rth at cygnus dot com>
On Fri, Aug 14, 1998 at 03:42:23PM -0400, David Edelsohn wrote:
> Maybe SUBREG is the problem, but I don't understand why these
> constant values cannot be propagated through SUBREGs.
They can. That is what the patch I posted was intended to show.
An indirectly related point, though, is using subregs also constrains
the register allocator is ways that perhaps we shouldn't. Even once
subreg propogation is fixed, there's a fair bit of x86 lossage due to
register allocation problems.
r~