LinuxThreads changes

[Ulrich Drepper <drepper@cygnus.com>]

Hi,

I've checked into the glibc cvs repository changes to LinuxThreads
which allow to use the cool method to implement fast access to the
thread decsriptor on x86 systems which Richard proposed and I
implemented last weekend.  The changes are not activated.  Take a look
at the end of sysdeps/i386/i686/pt-machine.h to see what you have to
do (simply remove the one comment).

To be able to use this mechanism you need the kernel 2.1.118 or later.
No other kernel probably ever worked.

BUT: the current code does not yet work.  I don't know why because I
had a quick&dirty version already running.  I'll try to fix this but
have some other things to do first.  So, somebody else might want to
look into this.  But be warned: I have no gcc which can grok this code
(grumble grumble...).


The improvements are gained by using macros to access the elements of
the thread struct.  Normally the access always happens through a self
pointer.  For ix86 and SPARC this is now different since we always
have access to the struct (either directly or relative to a fixed
register).

Xavier, I'm especially interested in hearing your comments.  I think
that we get very much better code for Intel since we have one more
free register (self is not needed).  Beside we'll be able to inline
some more functions.

-- 
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Ulrich Drepper  \    ,-------------------'   \  Sunnyvale, CA 94089 USA
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