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Re: Operand Scan times

From: Andreas Schwab <schwab at suse dot de>
To: Rask Ingemann Lambertsen <rask at sygehus dot dk>
Cc: Andrew MacLeod <amacleod at redhat dot com>, Andrew Haley <aph-gcc at littlepinkcloud dot COM>, gcc-patches <gcc-patches at gcc dot gnu dot org>
Date: Fri, 19 Oct 2007 23:57:25 +0200
Subject: Re: Operand Scan times
References: <1128366775.3080.7.camel@pain> <20071019171348.GY25795@sygehus.dk> <4718EC7E.8020203@redhat.com> <18200.60763.949670.992171@zebedee.pink> <4718F0A7.6040803@redhat.com> <20071019211818.GZ25795@sygehus.dk>

Rask Ingemann Lambertsen <rask@sygehus.dk> writes:

>    The extra check happens only when we would have aborted. It also appears
> to me that the return value calculation is needlessly complicated. A simple
> subtraction of the values is sufficient and faster on most CPUs.

The values are unsigned, thus the difference is also unsigned and the
conversion to int can trap.

Andreas.

-- 
Andreas Schwab, SuSE Labs, schwab@suse.de
SuSE Linux Products GmbH, Maxfeldstraße 5, 90409 Nürnberg, Germany
PGP key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

References:
- Re: Operand Scan times
  - From: Rask Ingemann Lambertsen
- Re: Operand Scan times
  - From: Andrew MacLeod
- Re: Operand Scan times
  - From: Andrew Haley
- Re: Operand Scan times
  - From: Andrew MacLeod
- Re: Operand Scan times
  - From: Rask Ingemann Lambertsen

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