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/* Licensed to the Apache Software Foundation (ASF) under one or more |
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* contributor license agreements. See the NOTICE file distributed with |
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* this work for additional information regarding copyright ownership. |
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* The ASF licenses this file to You under the Apache License, Version 2.0 |
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* (the "License"); you may not use this file except in compliance with |
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* the License. You may obtain a copy of the License at |
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* |
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* http://www.apache.org/licenses/LICENSE-2.0 |
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* |
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* Unless required by applicable law or agreed to in writing, software |
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* distributed under the License is distributed on an "AS IS" BASIS, |
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
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* See the License for the specific language governing permissions and |
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* limitations under the License. |
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*/ |
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|
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#include "apr_arch_atomic.h" |
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|
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#ifdef USE_ATOMICS_IA32 |
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|
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APR_DECLARE(apr_status_t) apr_atomic_init(apr_pool_t *p) |
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{ |
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return APR_SUCCESS; |
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} |
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|
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APR_DECLARE(apr_uint32_t) apr_atomic_read32(volatile apr_uint32_t *mem) |
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{ |
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return *mem; |
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} |
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|
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APR_DECLARE(void) apr_atomic_set32(volatile apr_uint32_t *mem, apr_uint32_t val) |
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{ |
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*mem = val; |
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} |
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|
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APR_DECLARE(apr_uint32_t) apr_atomic_add32(volatile apr_uint32_t *mem, apr_uint32_t val) |
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{ |
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asm volatile ("lock; xaddl %0,%1" |
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: "=r" (val), "=m" (*mem) |
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: "0" (val), "m" (*mem) |
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: "memory", "cc"); |
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return val; |
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} |
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|
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APR_DECLARE(void) apr_atomic_sub32(volatile apr_uint32_t *mem, apr_uint32_t val) |
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{ |
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asm volatile ("lock; subl %1, %0" |
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: /* no output */ |
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: "m" (*(mem)), "r" (val) |
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: "memory", "cc"); |
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} |
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|
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APR_DECLARE(apr_uint32_t) apr_atomic_inc32(volatile apr_uint32_t *mem) |
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{ |
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return apr_atomic_add32(mem, 1); |
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} |
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|
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APR_DECLARE(int) apr_atomic_dec32(volatile apr_uint32_t *mem) |
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{ |
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unsigned char prev; |
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|
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asm volatile ("lock; decl %0; setnz %1" |
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: "=m" (*mem), "=qm" (prev) |
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: "m" (*mem) |
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: "memory"); |
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|
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return prev; |
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} |
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|
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APR_DECLARE(apr_uint32_t) apr_atomic_cas32(volatile apr_uint32_t *mem, apr_uint32_t with, |
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apr_uint32_t cmp) |
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{ |
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apr_uint32_t prev; |
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|
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asm volatile ("lock; cmpxchgl %1, %2" |
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: "=a" (prev) |
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: "r" (with), "m" (*(mem)), "0"(cmp) |
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: "memory", "cc"); |
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return prev; |
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} |
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|
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APR_DECLARE(apr_uint32_t) apr_atomic_xchg32(volatile apr_uint32_t *mem, apr_uint32_t val) |
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{ |
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apr_uint32_t prev = val; |
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|
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asm volatile ("lock; xchgl %0, %1" |
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: "=r" (prev) |
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: "m" (*(mem)), "0"(prev) |
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: "memory"); |
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return prev; |
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} |
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|
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APR_DECLARE(void*) apr_atomic_casptr(volatile void **mem, void *with, const void *cmp) |
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{ |
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void *prev; |
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#if APR_SIZEOF_VOIDP == 4 |
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asm volatile ("lock; cmpxchgl %2, %1" |
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: "=a" (prev), "=m" (*mem) |
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: "r" (with), "m" (*mem), "0" (cmp)); |
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#elif APR_SIZEOF_VOIDP == 8 |
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asm volatile ("lock; cmpxchgq %q2, %1" |
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: "=a" (prev), "=m" (*mem) |
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: "r" ((unsigned long)with), "m" (*mem), |
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"0" ((unsigned long)cmp)); |
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#else |
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#error APR_SIZEOF_VOIDP value not supported |
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#endif |
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return prev; |
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} |
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|
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#endif /* USE_ATOMICS_IA32 */ |