glibc/sysdeps/sparc/sparc64/cpu_relax.S

68 lines
1.7 KiB
ArmAsm

/* CPU strand yielding for busy loops.
Copyright (C) 2012-2017 Free Software Foundation, Inc.
Contributed by David S. Miller (davem@davemloft.net)
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
.text
__cpu_relax_generic:
rd %ccr, %g0
rd %ccr, %g0
rd %ccr, %g0
retl
nop
.size __cpu_relax_generic,.-__cpu_relax_generic
__cpu_relax_pause:
wr %g0, 128, %asr27
retl
nop
.size __cpu_relax_pause,.-__cpu_relax_pause
ENTRY(__cpu_relax)
.type __cpu_relax, @gnu_indirect_function
# ifdef SHARED
SETUP_PIC_REG_LEAF(o3, o5)
# endif
set HWCAP_SPARC_PAUSE, %o1
andcc %o0, %o1, %g0
be 1f
nop
# ifdef SHARED
sethi %gdop_hix22(__cpu_relax_pause), %o1
xor %o1, %gdop_lox10(__cpu_relax_pause), %o1
# else
set __cpu_relax_pause, %o1
# endif
ba 10f
nop
1:
# ifdef SHARED
sethi %gdop_hix22(__cpu_relax_generic), %o1
xor %o1, %gdop_lox10(__cpu_relax_generic), %o1
# else
set __cpu_relax_generic, %o1
# endif
10:
# ifdef SHARED
add %o3, %o1, %o1
# endif
retl
mov %o1, %o0
END(__cpu_relax)