optimization/9319: slower code generated for simple loop on linux

[amnon_cohen@yahoo.com]

>Number:         9319
>Category:       optimization
>Synopsis:       slower code generated for simple loop on linux
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          pessimizes-code
>Submitter-Id:   net
>Arrival-Date:   Wed Jan 15 02:16:02 PST 2003
>Closed-Date:
>Last-Modified:
>Originator:     amnon_cohen@yahoo.com
>Release:        gcc 3.2.1
>Organization:
>Environment:
Red Hat Linux 2.3.9-13
>Description:
For the simple loop attached gcc3.2.1 -O3 produces code
which runs 40% slower than code produced by gcc 3.0

>How-To-Repeat:
gcc -c -O3 loop3.c
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
----gnatsweb-attachment----
Content-Type: application/octet-stream; name="loop3.c"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="loop3.c"

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