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Re: [patch, fortran-dev] Use fixed variable sizes for stride calculations

From: Thomas Koenig <tkoenig at netcologne dot de>
To: "fortran at gcc dot gnu dot org" <fortran at gcc dot gnu dot org>, gcc-patches <gcc-patches at gcc dot gnu dot org>
Date: Wed, 11 Apr 2012 09:51:14 +0200
Subject: Re: [patch, fortran-dev] Use fixed variable sizes for stride calculations
References: <4F6DD691.9010907@netcologne.de>

Hi,

this patch uses division by known sizes (which can usually be replaced
by a simple shift because intrinsics have sizes of power of two) instead
of division by the size extracted from the array descriptor itself.

This should save about 20 cycles for a single calculation.

I'll go through the rest of the library to identify other possibilities
for this.

Regression-tested, no new failures.

OK for the branch?

Full patch at http://gcc.gnu.org/ml/fortran/2012-03/msg00120.html

Ping?

Thomas

Follow-Ups:
- Re: [patch, fortran-dev] Use fixed variable sizes for stride calculations
  - From: Janne Blomqvist

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