[src/trunk]: src/sys/arch/aarch64/aarch64 use stp if possible.

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

details:   https://anonhg.NetBSD.org/src/rev/1a29418d463b
branches:  trunk
changeset: 366676:1a29418d463b
user:      ryo <ryo%NetBSD.org@localhost>
date:      Tue Jun 07 04:12:10 2022 +0000

description:
use stp if possible.

diffstat:

 sys/arch/aarch64/aarch64/cpuswitch.S |  13 +++++++++----
 1 files changed, 9 insertions(+), 4 deletions(-)

diffs (34 lines):

diff -r bb0372f9cc57 -r 1a29418d463b sys/arch/aarch64/aarch64/cpuswitch.S
--- a/sys/arch/aarch64/aarch64/cpuswitch.S      Mon Jun 06 13:28:55 2022 +0000
+++ b/sys/arch/aarch64/aarch64/cpuswitch.S      Tue Jun 07 04:12:10 2022 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: cpuswitch.S,v 1.36 2022/06/03 19:59:59 ryo Exp $ */
+/* $NetBSD: cpuswitch.S,v 1.37 2022/06/07 04:12:10 ryo Exp $ */
 
 /*-
  * Copyright (c) 2014, 2020 The NetBSD Foundation, Inc.
@@ -38,7 +38,7 @@
 #include "opt_ddb.h"
 #include "opt_kasan.h"
 
-RCSID("$NetBSD: cpuswitch.S,v 1.36 2022/06/03 19:59:59 ryo Exp $")
+RCSID("$NetBSD: cpuswitch.S,v 1.37 2022/06/07 04:12:10 ryo Exp $")
 
        ARMV8_DEFINE_OPTIONS
 
@@ -61,8 +61,13 @@
        stp     x27, x28, [sp, #TF_X27]
        stp     x29, x30, [sp, #TF_X29]
 #ifdef DDB
-       str     lr, [sp, #TF_PC]                /* for backtrace */
-       str     xzr, [sp, #TF_SP]               /* mark as switchframe */
+       /* mark as switchframe for backtrace */
+       .if TF_SP + 8 == TF_PC
+       stp     xzr, lr, [sp, #TF_SP]
+       .else
+       str     xzr, [sp, #TF_SP]
+       str     lr, [sp, #TF_PC]
+       .endif
 #endif
 
        /*