[src/trunk]: src/sys/arch/amd64/include Remove the incorrect comment about a ...

[dsl <dsl%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/475cba01e2cd
branches:  trunk
changeset: 783342:475cba01e2cd
user:      dsl <dsl%NetBSD.org@localhost>
date:      Sat Dec 15 22:39:04 2012 +0000

description:
Remove the incorrect comment about a (now deleted) pad field added
to make __fpregs be 16-byte aligned within ucontext_t.
I doubt that has been true for years!
Since the __fpregs field isn't accessed by fxsave it doesn't matter.
There is a lot of type fubar here, at leat mark the char[] __aligned(8).

diffstat:

 sys/arch/amd64/include/mcontext.h |  12 +++++-------
 1 files changed, 5 insertions(+), 7 deletions(-)

diffs (27 lines):

diff -r bfd0fcbe1e3f -r 475cba01e2cd sys/arch/amd64/include/mcontext.h
--- a/sys/arch/amd64/include/mcontext.h Sat Dec 15 22:23:31 2012 +0000
+++ b/sys/arch/amd64/include/mcontext.h Sat Dec 15 22:39:04 2012 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: mcontext.h,v 1.15 2012/05/21 14:15:17 martin Exp $     */
+/*     $NetBSD: mcontext.h,v 1.16 2012/12/15 22:39:04 dsl Exp $        */
 
 /*-
  * Copyright (c) 1999 The NetBSD Foundation, Inc.
@@ -52,13 +52,11 @@
 
 /*
  * Floating point register state
+ * The format of __fpregset_t is that of the fxsave instruction
+ * which requires 16 byte alignment. However the mcontext version
+ * is never directly accessed.
  */
-typedef char __fpregset_t[512];
-
-/*
- * The padding below is to make __fpregs have a 16-byte aligned offset
- * within ucontext_t.
- */
+typedef char __fpregset_t[512] __aligned(8);
 
 typedef struct {
        __gregset_t     __gregs;