c/2308: x86_64 opcode generated for i686

[drepper@redhat.com]

>Number:         2308
>Category:       c
>Synopsis:       x86_64 opcode generated for i686
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    unassigned
>State:          open
>Class:          sw-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Mar 16 22:36:00 PST 2001
>Closed-Date:
>Last-Modified:
>Originator:     Ulrich Drepper
>Release:        gcc version 3.1 20010316 (experimental)
>Organization:
>Environment:
Linux/x86
>Description:
Compiling the attached file with

  gcc -c -O2 ffsll.i

with today's (2000-3-16) gcc leads to the message

/tmp/ccdIDgSe.s:26: Error: suffix or operands invalid for `bsf'
/tmp/ccdIDgSe.s:43: Error: suffix or operands invalid for `bsf'

What happens is that the registers in the asm statements are substituted inccorectly:

        bsfl %rsi,%ebx

This seems to be the syntax for the extended x86_64 registers but of course is very wrong on i686.
>How-To-Repeat:
Compile attached file with

  gcc -c -O2 ffsll.i
>Fix:

>Release-Note:
>Audit-Trail:
>Unformatted:
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