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From: cinap_lenrek@felloff.net
To: 9fans@9fans.net
Subject: [9fans] extern register
Date: Sat, 19 Jul 2014 03:57:14 +0200	[thread overview]
Message-ID: <ff0d3b569d90e25239067a766a061332@felloff.net> (raw)

the amd64 compiler reserves R14 and R15 for extern register
declarations. these are used by the kernel for the mach
and up pointers, but currently are not preserved during
system calls.

would it make sense to save and restore the two registers
on syscall entry/exit, so userspace programs could make use
of them for per process data?

--
cinap



             reply	other threads:[~2014-07-19  1:57 UTC|newest]

Thread overview: 15+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2014-07-19  1:57 cinap_lenrek [this message]
2014-07-19  2:04 ` erik quanstrom
2014-07-19  2:19   ` erik quanstrom
2014-07-19  2:33     ` cinap_lenrek
2014-07-19  2:37       ` erik quanstrom
2014-07-19  2:27   ` cinap_lenrek
2014-07-19  2:41     ` erik quanstrom
2014-07-19 12:29 ` Aram Hăvărneanu
2014-07-19 12:42 ` Charles Forsyth
2014-07-19 14:38   ` Aram Hăvărneanu
2014-07-19 14:55     ` erik quanstrom
2014-07-19 15:53       ` Aram Hăvărneanu
2014-07-20  1:42   ` cinap_lenrek
2014-07-20 10:12     ` Aram Hăvărneanu
2014-07-20 16:35       ` cinap_lenrek

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