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From: Geert Bosch <bosch@gnat.com>
To: "Ulrich Weigand" <Ulrich.Weigand@de.ibm.com>
Cc: gcc@gcc.gnu.org
Subject: Re: RFA: Ada variable-sized objects, bit_size_type == TImode, and divti3
Date: Thu, 20 Mar 2003 23:18:00 -0000	[thread overview]
Message-ID: <02AD3AA5-5B22-11D7-9722-00039344BF4A@gnat.com> (raw)
In-Reply-To: <OFBAB4CE9A.60EE15CF-ONC1256CEF.0072786F@de.ibm.com>


On Thursday, Mar 20, 2003, at 15:58 America/New_York, Ulrich Weigand 
wrote:

> However, I'm wondering:
>
> - does bit_size_type really need to be TImode
Richard Kenner would be best qualified to answer this, but he is out
of town until tuesday.
> - if so, shouldn't these special cases be implemented more efficiently
>   somewhere (we divide by an integer constant 8 here)

This would be nice, but I'm not sure this is most pressing. It seems
unlikely to me that the constructs generating these long divisions
would occur in performance-sensitive code.
In general, for 64-bit arithmetic operations on 32-bit targets, there
are many cases where one of the operands is constant and simpler
code code be generated inline instead.

> - in general, are we really supposed to need TImode division
> How does this work on other 64-bit platforms?

Other 64-bit platforms define TImode division.

   -Geert

  parent reply	other threads:[~2003-03-20 22:19 UTC|newest]

Thread overview: 19+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2003-03-20 21:55 Ulrich Weigand
2003-03-20 22:31 ` Richard Henderson
2003-03-20 23:18 ` Geert Bosch [this message]
2003-03-21  0:00 ` Janis Johnson
2003-03-20 22:35 Ulrich Weigand
2003-03-20 23:44 ` Richard Henderson
2003-03-21  0:25   ` Neil Booth
2003-03-21  1:58   ` Ulrich Weigand
2003-03-21  7:46     ` Richard Henderson
2003-03-21 16:27       ` Ulrich Weigand
2003-03-21 20:25       ` Ulrich Weigand
2003-03-21  2:09 Ulrich Weigand
2003-03-24 11:08 Richard Kenner
2003-03-31 20:16 Richard Kenner
2003-04-01 19:26 Ulrich Weigand
2003-04-01 22:53 Richard Kenner
2003-04-02 15:36 Ulrich Weigand
2003-04-02 15:36 Richard Kenner
2003-04-02 15:43 Ulrich Weigand

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