sam-t2/sam/cpus/vonk/bl/lib/utl/src/BL_Atomic.s

/*
* ========== Copyright Header Begin ==========================================
*
* OpenSPARC T2 Processor File: BL_Atomic.s
* Copyright (c) 2006 Sun Microsystems, Inc.  All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES.
*
* The above named program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public
* License version 2 as published by the Free Software Foundation.
*
* The above named program 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
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA.
*
* ========== Copyright Header End ============================================
*/
#if defined(ARCH_X64)

        .text

/*============================================================================*\
 * int64_t bl_atomic_add64( int64_t* var, int64_t val )
 *
 * Implement atomic 64bit add with casxa, The value returned is the old *var
\*============================================================================*/

        .align  16
        .globl  bl_atomic_add64
        .type   bl_atomic_add64, @function
bl_atomic_add64:
        movq    %rsi,%rax
        lock
        xaddq   %rax,(%rdi)
        ret
        .size   bl_atomic_add64, [.-bl_atomic_add64]

/*============================================================================*\
 * int32_t bl_atomic_add32( int32_t* var, int32_t val )
 *
 * Implement atomic 32bit add with casa. The value returned in the old *var
\*============================================================================*/

        .align  16
        .globl  bl_atomic_add32
        .type   bl_atomic_add32, @function
bl_atomic_add32:
        movl    %esi,%eax
        lock
        xaddl   %eax,(%rdi)
        ret
        .size   bl_atomic_add32, [.-bl_atomic_add32]

#else

.section        ".text"

/*============================================================================*\
 * int64_t bl_atomic_add64( int64_t* var, int64_t val )
 *
 * Implement atomic 64bit add with casxa, The value returned is the old *var
\*============================================================================*/

.global bl_atomic_add64
.type   bl_atomic_add64, #function

bl_atomic_add64:
        ldx     [%o0],%o2               /* Load *var */
1:
        add     %o2,%o1,%o3             /* Goal is *var + val */
        casxa   [%o0]0x80,%o2,%o3       /* */
        cmp     %o2,%o3                 /* Test if we added to same *var value */
        bne     %xcc,1b                 /* If not we did not */
        mov     %o3,%o2                 /* Try again with new *var (casxa is ldx) */
        retl
        mov     %o3,%o0                 /* Return previous value */


/*============================================================================*\
 * int32_t bl_atomic_add32( int32_t* var, int32_t val )
 *
 * Implement atomic 32bit add with casa. The value returned in the old *var
\*============================================================================*/

.global bl_atomic_add32
.type   bl_atomic_add32, #function

bl_atomic_add32:
        ld      [%o0],%o2               /* Load *var */
1:
        add     %o2,%o1,%o3             /* Goal is *var = val + *var */
        casa    [%o0]0x80,%o2,%o3       /* */
        cmp     %o2,%o3                 /* Test if we added to same *var value */
        bne     %icc,1b                 /* If not we did not */
        mov     %o3,%o2                 /* Try again with new *var (casxa is ldx) */
        retl
        sra     %o3,0,%o0               /* Return previous value (32 bit) */

#endif