/* * Copyright (C) 2008 The Android Open Source Project * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * *      http://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */    .text    .align        .global android_atomic_write        .global android_atomic_inc    .global android_atomic_dec        .global android_atomic_add    .global android_atomic_and    .global android_atomic_or        .global android_atomic_swap        .global android_atomic_cmpxchg    /* FIXME: On SMP systems memory barriers may be needed */#warning  "this file is not safe with SMP systems"/* * ---------------------------------------------------------------------------- * android_atomic_write * input: r0=value, r1=address * output: void */android_atomic_write:1:  ldrex   r12, [r1]    strex   r12, r0, [r1]    cmp     r12, #0    bne     1b    bx      lr/* * ---------------------------------------------------------------------------- * android_atomic_inc * input: r0 = address * output: r0 = old value */ android_atomic_inc:    mov     r12, r01:  ldrex   r0, [r12]    add     r2, r0, #1    strex   r1, r2, [r12]    cmp     r1, #0    bxeq    lr    b       1b/* * ---------------------------------------------------------------------------- * android_atomic_dec * input: r0=address * output: r0 = old value */ android_atomic_dec:    mov     r12, r01:  ldrex   r0, [r12]    sub     r2, r0, #1    strex   r1, r2, [r12]    cmp     r1, #0    bxeq    lr    b       1b    /* * ---------------------------------------------------------------------------- * android_atomic_add * input: r0=value, r1=address * output: r0 = old value */android_atomic_add:    mov     r12, r01:  ldrex   r0, [r1]    add     r2, r0, r12    strex   r3, r2, [r1]    cmp     r3, #0    bxeq    lr    b       1b    /* * ---------------------------------------------------------------------------- * android_atomic_and * input: r0=value, r1=address * output: r0 = old value */android_atomic_and:    mov     r12, r01:  ldrex   r0, [r1]    and     r2, r0, r12    strex   r3, r2, [r1]    cmp     r3, #0    bxeq    lr    b       1b    /* * ---------------------------------------------------------------------------- * android_atomic_or * input: r0=value, r1=address * output: r0 = old value */android_atomic_or:    mov     r12, r01:  ldrex   r0, [r1]    orr     r2, r0, r12    strex   r3, r2, [r1]    cmp     r3, #0    bxeq    lr    b       1b/* * ---------------------------------------------------------------------------- * android_atomic_swap * input: r0=value, r1=address * output: r0 = old value */android_atomic_swap:    swp     r0, r0, [r1]    bx      lr/* * ---------------------------------------------------------------------------- * android_atomic_cmpxchg * input: r0=oldvalue, r1=newvalue, r2=address * output: r0 = 0 (xchg done) or non-zero (xchg not done) */android_atomic_cmpxchg:    mov     r12, r1    ldrex   r3, [r2]    eors    r0, r0, r3    strexeq r0, r12, [r2]    bx      lr/* * ---------------------------------------------------------------------------- * android_atomic_cmpxchg_64 * input: r0-r1=oldvalue, r2-r3=newvalue, arg4 (on stack)=address * output: r0 = 0 (xchg done) or non-zero (xchg not done) *//* TODO: NEED IMPLEMENTATION FOR THIS ARCHITECTURE */