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* Copyright (C) 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC")
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* Permission to use, copy, modify, and/or distribute this software for any
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* purpose with or without fee is hereby granted, provided that the above
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* copyright notice and this permission notice appear in all copies.
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* THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
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* REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
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* AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
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* INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
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* LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
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* OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
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* PERFORMANCE OF THIS SOFTWARE.
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/* $Id: atomic.h,v 1.4.128.2 2008/01/24 23:46:26 tbox Exp $ */
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#define ISC_ATOMIC_H 1
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#include <isc/platform.h>
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#include <isc/types.h>
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#ifdef ISC_PLATFORM_USEGCCASM
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/* We share the gcc-version with x86_32 */
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#error "impossible case. check build configuration"
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#elif defined(ISC_PLATFORM_USESTDASM)
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* The followings are "generic" assembly code which implements the same
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* functionality in case the gcc extension cannot be used. It should be
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* better to avoid inlining below, since we directly refer to specific
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* registers for arguments, which would not actually correspond to the
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* intended address or value in the embedded mnemonic.
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#include <isc/util.h> /* for 'UNUSED' macro */
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isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
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#ifdef ISC_PLATFORM_USETHREADS
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* XXX: assume %eax will be used as the return value.
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#ifdef ISC_PLATFORM_HAVEXADDQ
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isc_atomic_xaddq(isc_int64_t *p, isc_int64_t val) {
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#ifdef ISC_PLATFORM_USETHREADS
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"xaddq %rax, (%rdx)\n"
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* XXX: assume %rax will be used as the return value.
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isc_atomic_store(isc_int32_t *p, isc_int32_t val) {
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#ifdef ISC_PLATFORM_USETHREADS
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"xchgl (%rax), %edx\n"
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* XXX: assume %rax will be used as the return value.
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isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
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#ifdef ISC_PLATFORM_USETHREADS
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* If (%rdi) == %eax then (%rdi) := %edx.
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* %eax is set to old (%ecx), which will be the return value.
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"cmpxchgl %ecx, (%rdx)"
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#else /* !ISC_PLATFORM_USEGCCASM && !ISC_PLATFORM_USESTDASM */
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#error "unsupported compiler. disable atomic ops by --disable-atomic"
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#endif /* ISC_ATOMIC_H */