Subversion Repositories planix.SVN

TEXT ainc(SB), $0       /* long ainc(long *); */
        MOVL    addr+0(FP), BX
ainclp:
        MOVL    (BX), AX
        MOVL    AX, CX
        INCL    CX
        LOCK
        BYTE    $0x0F; BYTE $0xB1; BYTE $0x0B   /* CMPXCHGL CX, (BX) */
        JNZ     ainclp
        MOVL    CX, AX
        RET

TEXT adec(SB), $0       /* long adec(long*); */
        MOVL    addr+0(FP), BX
adeclp:
        MOVL    (BX), AX
        MOVL    AX, CX
        DECL    CX
        LOCK
        BYTE    $0x0F; BYTE $0xB1; BYTE $0x0B   /* CMPXCHGL CX, (BX) */
        JNZ     adeclp
        MOVL    CX, AX
        RET

/*
 * int cas32(u32int *p, u32int ov, u32int nv);
 * int cas(uint *p, int ov, int nv);
 * int casp(void **p, void *ov, void *nv);
 * int casl(ulong *p, ulong ov, ulong nv);
 */

/*
 * CMPXCHG (CX), DX: 0000 1111 1011 000w oorr rmmm,
 * mmm = CX = 001; rrr = DX = 010
 */

#define CMPXCHG         BYTE $0x0F; BYTE $0xB1; BYTE $0x11

TEXT    cas32+0(SB),0,$0
TEXT    cas+0(SB),0,$0
TEXT    casp+0(SB),0,$0
TEXT    casl+0(SB),0,$0
        MOVL    p+0(FP), CX
        MOVL    ov+4(FP), AX
        MOVL    nv+8(FP), DX
        LOCK
        CMPXCHG
        JNE     fail
        MOVL    $1,AX
        RET
fail:
        MOVL    $0,AX
        RET

/*
 * int cas64(u64int *p, u64int ov, u64int nv);
 */

/*
 * CMPXCHG64 (DI): 0000 1111 1100 0111 0000 1110,
 */

#define CMPXCHG64               BYTE $0x0F; BYTE $0xC7; BYTE $0x0F

TEXT    cas64+0(SB),0,$0
        MOVL    p+0(FP), DI
        MOVL    ov+0x4(FP), AX
        MOVL    ov+0x8(FP), DX
        MOVL    nv+0xc(FP), BX
        MOVL    nv+0x10(FP), CX
        LOCK
        CMPXCHG64
        JNE     fail
        MOVL    $1,AX
        RET