*BSD News Article 53978


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From: hiroshi@teine.chem2.hokudai.ac.jp (Hiroshi Murakami)
Newsgroups: comp.unix.bsd.freebsd.misc
Subject: 8 byte alignment for double variables.
Date: 30 Oct 1995 15:45:11 GMT
Organization: Hokkaido Univ., Sapporo, Japan.
Lines: 8
Message-ID: <472ru7$8pm@nyx.eos.hokudai.ac.jp>
NNTP-Posting-Host: teine.chem2.hokudai.ac.jp

I found gcc comes with FreeBSD2.1.0 does not always allocate the
double variable 8 bytes aligned. This degrades the performance
for the Pentium quite a lot. (halve the fp performance for
load/store and also arithmetics.)

The pointers allocated by malloc always aligned but
global or local variables either static or auto do 
not always aligned.