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diff --git a/lib/isc/x86_32/include/isc/atomic.h b/lib/isc/x86_32/include/isc/atomic.h
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+/*
+ * Copyright (C) 2005, 2007, 2008 Internet Systems Consortium, Inc. ("ISC")
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS. IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+/* $Id: atomic.h,v 1.10 2008/01/24 23:47:00 tbox Exp $ */
+
+#ifndef ISC_ATOMIC_H
+#define ISC_ATOMIC_H 1
+
+#include <isc/platform.h>
+#include <isc/types.h>
+
+#ifdef ISC_PLATFORM_USEGCCASM
+/*
+ * This routine atomically increments the value stored in 'p' by 'val', and
+ * returns the previous value.
+ */
+static __inline__ isc_int32_t
+isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
+ isc_int32_t prev = val;
+
+ __asm__ volatile(
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+ "xadd %0, %1"
+ :"=q"(prev)
+ :"m"(*p), "0"(prev)
+ :"memory", "cc");
+
+ return (prev);
+}
+
+#ifdef ISC_PLATFORM_HAVEXADDQ
+static __inline__ isc_int64_t
+isc_atomic_xaddq(isc_int64_t *p, isc_int64_t val) {
+ isc_int64_t prev = val;
+
+ __asm__ volatile(
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+ "xaddq %0, %1"
+ :"=q"(prev)
+ :"m"(*p), "0"(prev)
+ :"memory", "cc");
+
+ return (prev);
+}
+#endif /* ISC_PLATFORM_HAVEXADDQ */
+
+/*
+ * This routine atomically stores the value 'val' in 'p'.
+ */
+static __inline__ void
+isc_atomic_store(isc_int32_t *p, isc_int32_t val) {
+ __asm__ volatile(
+#ifdef ISC_PLATFORM_USETHREADS
+ /*
+ * xchg should automatically lock memory, but we add it
+ * explicitly just in case (it at least doesn't harm)
+ */
+ "lock;"
+#endif
+
+ "xchgl %1, %0"
+ :
+ : "r"(val), "m"(*p)
+ : "memory");
+}
+
+/*
+ * This routine atomically replaces the value in 'p' with 'val', if the
+ * original value is equal to 'cmpval'. The original value is returned in any
+ * case.
+ */
+static __inline__ isc_int32_t
+isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
+ __asm__ volatile(
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+ "cmpxchgl %1, %2"
+ : "=a"(cmpval)
+ : "r"(val), "m"(*p), "a"(cmpval)
+ : "memory");
+
+ return (cmpval);
+}
+
+#elif defined(ISC_PLATFORM_USESTDASM)
+/*
+ * The followings are "generic" assembly code which implements the same
+ * functionality in case the gcc extension cannot be used. It should be
+ * better to avoid inlining below, since we directly refer to specific
+ * positions of the stack frame, which would not actually point to the
+ * intended address in the embedded mnemonic.
+ */
+#include <isc/util.h> /* for 'UNUSED' macro */
+
+static isc_int32_t
+isc_atomic_xadd(isc_int32_t *p, isc_int32_t val) {
+ UNUSED(p);
+ UNUSED(val);
+
+ __asm (
+ "movl 8(%ebp), %ecx\n"
+ "movl 12(%ebp), %edx\n"
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+ "xadd %edx, (%ecx)\n"
+
+ /*
+ * set the return value directly in the register so that we
+ * can avoid guessing the correct position in the stack for a
+ * local variable.
+ */
+ "movl %edx, %eax"
+ );
+}
+
+static void
+isc_atomic_store(isc_int32_t *p, isc_int32_t val) {
+ UNUSED(p);
+ UNUSED(val);
+
+ __asm (
+ "movl 8(%ebp), %ecx\n"
+ "movl 12(%ebp), %edx\n"
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+ "xchgl (%ecx), %edx\n"
+ );
+}
+
+static isc_int32_t
+isc_atomic_cmpxchg(isc_int32_t *p, isc_int32_t cmpval, isc_int32_t val) {
+ UNUSED(p);
+ UNUSED(cmpval);
+ UNUSED(val);
+
+ __asm (
+ "movl 8(%ebp), %ecx\n"
+ "movl 12(%ebp), %eax\n" /* must be %eax for cmpxchgl */
+ "movl 16(%ebp), %edx\n"
+#ifdef ISC_PLATFORM_USETHREADS
+ "lock;"
+#endif
+
+ /*
+ * If (%ecx) == %eax then (%ecx) := %edx.
+ % %eax is set to old (%ecx), which will be the return value.
+ */
+ "cmpxchgl %edx, (%ecx)"
+ );
+}
+#else /* !ISC_PLATFORM_USEGCCASM && !ISC_PLATFORM_USESTDASM */
+
+#error "unsupported compiler. disable atomic ops by --disable-atomic"
+
+#endif
+#endif /* ISC_ATOMIC_H */