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authorJoseph Myers <joseph@codesourcery.com>2015-09-11 20:00:19 +0000
committerJoseph Myers <joseph@codesourcery.com>2015-09-11 20:00:19 +0000
commitde071d199a8578055edf2722114788ae749823aa (patch)
treee873095059e9624873d9629a68885afebaf6fbee /sysdeps/mips/atomic-machine.h
parent20f366af163db7b9243a6bfd5d4d42ad6b3214c0 (diff)
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Move bits/atomic.h to atomic-machine.h (bug 14912).
It was noted in
<https://sourceware.org/ml/libc-alpha/2012-09/msg00305.html> that the
bits/*.h naming scheme should only be used for installed headers.
This patch renames bits/atomic.h to atomic-machine.h to follow that
convention.

This is the only change in this series that needs to change the
filename rather than simply removing a directory level (because both
atomic.h and bits/atomic.h exist at present).

Tested for x86_64 (testsuite, and that installed stripped shared
libraries are unchanged by the patch).

	[BZ #14912]
	* sysdeps/aarch64/bits/atomic.h: Move to ...
	* sysdeps/aarch64/atomic-machine.h: ...here.
	(_AARCH64_BITS_ATOMIC_H): Rename macro to
	_AARCH64_ATOMIC_MACHINE_H.
	* sysdeps/alpha/bits/atomic.h: Move to ...
	* sysdeps/alpha/atomic-machine.h: ...here.
	* sysdeps/arm/bits/atomic.h: Move to ...
	* sysdeps/arm/atomic-machine.h: ...here.  Update comments.
	* bits/atomic.h: Move to ...
	* sysdeps/generic/atomic-machine.h: ...here.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/i386/bits/atomic.h: Move to ...
	* sysdeps/i386/atomic-machine.h: ...here.
	* sysdeps/ia64/bits/atomic.h: Move to ...
	* sysdeps/ia64/atomic-machine.h: ...here.
	* sysdeps/m68k/coldfire/bits/atomic.h: Move to ...
	* sysdeps/m68k/coldfire/atomic-machine.h: ...here.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/m68k/m680x0/m68020/bits/atomic.h: Move to ...
	* sysdeps/m68k/m680x0/m68020/atomic-machine.h: ...here.
	* sysdeps/microblaze/bits/atomic.h: Move to ...
	* sysdeps/microblaze/atomic-machine.h: ...here.
	* sysdeps/mips/bits/atomic.h: Move to ...
	* sysdeps/mips/atomic-machine.h: ...here.
	(_MIPS_BITS_ATOMIC_H): Rename macro to _MIPS_ATOMIC_MACHINE_H.
	* sysdeps/powerpc/bits/atomic.h: Move to ...
	* sysdeps/powerpc/atomic-machine.h: ...here.  Update comments.
	* sysdeps/powerpc/powerpc32/bits/atomic.h: Move to ...
	* sysdeps/powerpc/powerpc32/atomic-machine.h: ...here.  Update
	comments.  Include <atomic-machine.h> instead of <bits/atomic.h>.
	* sysdeps/powerpc/powerpc64/bits/atomic.h: Move to ...
	* sysdeps/powerpc/powerpc64/atomic-machine.h: ...here.  Include
	<atomic-machine.h> instead of <bits/atomic.h>.
	* sysdeps/s390/bits/atomic.h: Move to ...
	* sysdeps/s390/atomic-machine.h: ...here.
	* sysdeps/sparc/sparc32/bits/atomic.h: Move to ...
	* sysdeps/sparc/sparc32/atomic-machine.h: ...here.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/sparc/sparc32/sparcv9/bits/atomic.h: Move to ...
	* sysdeps/sparc/sparc32/sparcv9/atomic-machine.h: ...here.
	* sysdeps/sparc/sparc64/bits/atomic.h: Move to ...
	* sysdeps/sparc/sparc64/atomic-machine.h: ...here.
	* sysdeps/tile/bits/atomic.h: Move to ...
	* sysdeps/tile/atomic-machine.h: ...here.
	* sysdeps/tile/tilegx/bits/atomic.h: Move to ...
	* sysdeps/tile/tilegx/atomic-machine.h: ...here.  Include
	<sysdeps/tile/atomic-machine.h> instead of
	<sysdeps/tile/bits/atomic.h>.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/tile/tilepro/bits/atomic.h: Move to ...
	* sysdeps/tile/tilepro/atomic-machine.h: ...here.  Include
	<sysdeps/tile/atomic-machine.h> instead of
	<sysdeps/tile/bits/atomic.h>.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/unix/sysv/linux/arm/bits/atomic.h: Move to ...
	* sysdeps/unix/sysv/linux/arm/atomic-machine.h: ...here.  Include
	<sysdeps/arm/atomic-machine.h> instead of
	<sysdeps/arm/bits/atomic.h>.
	* sysdeps/unix/sysv/linux/hppa/bits/atomic.h: Move to ...
	* sysdeps/unix/sysv/linux/hppa/atomic-machine.h: ...here.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/unix/sysv/linux/m68k/coldfire/bits/atomic.h: Move to ...
	* sysdeps/unix/sysv/linux/m68k/coldfire/atomic-machine.h: ...here.
	(_BITS_ATOMIC_H): Rename macro to _ATOMIC_MACHINE_H.
	* sysdeps/unix/sysv/linux/nios2/bits/atomic.h: Move to ...
	* sysdeps/unix/sysv/linux/nios2/atomic-machine.h: ...here.
	(_NIOS2_BITS_ATOMIC_H): Rename macro to _NIOS2_ATOMIC_MACHINE_H.
	* sysdeps/unix/sysv/linux/sh/bits/atomic.h: Move to ...
	* sysdeps/unix/sysv/linux/sh/atomic-machine.h: ...here.
	* sysdeps/x86_64/bits/atomic.h: Move to ...
	* sysdeps/x86_64/atomic-machine.h: ...here.
	* include/atomic.h: Include <atomic-machine.h> instead of
	<bits/atomic.h>.
Diffstat (limited to 'sysdeps/mips/atomic-machine.h')
-rw-r--r--sysdeps/mips/atomic-machine.h503
1 files changed, 503 insertions, 0 deletions
diff --git a/sysdeps/mips/atomic-machine.h b/sysdeps/mips/atomic-machine.h
new file mode 100644
index 0000000000..6db8fee1d4
--- /dev/null
+++ b/sysdeps/mips/atomic-machine.h
@@ -0,0 +1,503 @@
+/* Low-level functions for atomic operations. Mips version.
+   Copyright (C) 2005-2015 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#ifndef _MIPS_ATOMIC_MACHINE_H
+#define _MIPS_ATOMIC_MACHINE_H 1
+
+#include <stdint.h>
+#include <inttypes.h>
+#include <sgidefs.h>
+
+typedef int32_t atomic32_t;
+typedef uint32_t uatomic32_t;
+typedef int_fast32_t atomic_fast32_t;
+typedef uint_fast32_t uatomic_fast32_t;
+
+typedef int64_t atomic64_t;
+typedef uint64_t uatomic64_t;
+typedef int_fast64_t atomic_fast64_t;
+typedef uint_fast64_t uatomic_fast64_t;
+
+typedef intptr_t atomicptr_t;
+typedef uintptr_t uatomicptr_t;
+typedef intmax_t atomic_max_t;
+typedef uintmax_t uatomic_max_t;
+
+#if _MIPS_SIM == _ABIO32 && __mips < 2
+#define MIPS_PUSH_MIPS2 ".set	mips2\n\t"
+#else
+#define MIPS_PUSH_MIPS2
+#endif
+
+#if _MIPS_SIM == _ABIO32 || _MIPS_SIM == _ABIN32
+#define __HAVE_64B_ATOMICS 0
+#else
+#define __HAVE_64B_ATOMICS 1
+#endif
+
+/* See the comments in <sys/asm.h> about the use of the sync instruction.  */
+#ifndef MIPS_SYNC
+# define MIPS_SYNC	sync
+#endif
+
+/* Certain revisions of the R10000 Processor need an LL/SC Workaround
+   enabled.  Revisions before 3.0 misbehave on atomic operations, and
+   Revs 2.6 and lower deadlock after several seconds due to other errata.
+
+   To quote the R10K Errata:
+      Workaround: The basic idea is to inhibit the four instructions
+      from simultaneously becoming active in R10000. Padding all
+      ll/sc sequences with nops or changing the looping branch in the
+      routines to a branch likely (which is always predicted taken
+      by R10000) will work. The nops should go after the loop, and the
+      number of them should be 28. This number could be decremented for
+      each additional instruction in the ll/sc loop such as the lock
+      modifier(s) between the ll and sc, the looping branch and its
+      delay slot. For typical short routines with one ll/sc loop, any
+      instructions after the loop could also count as a decrement. The
+      nop workaround pollutes the cache more but would be a few cycles
+      faster if all the code is in the cache and the looping branch
+      is predicted not taken.  */
+
+
+#ifdef _MIPS_ARCH_R10000
+#define R10K_BEQZ_INSN "beqzl"
+#else
+#define R10K_BEQZ_INSN "beqz"
+#endif
+
+#define MIPS_SYNC_STR_2(X) #X
+#define MIPS_SYNC_STR_1(X) MIPS_SYNC_STR_2(X)
+#define MIPS_SYNC_STR MIPS_SYNC_STR_1(MIPS_SYNC)
+
+#if __GNUC_PREREQ (4, 8) || (defined __mips16 && __GNUC_PREREQ (4, 7))
+/* The __atomic_* builtins are available in GCC 4.7 and later, but MIPS
+   support for their efficient implementation was added only in GCC 4.8.
+   We still want to use them even with GCC 4.7 for MIPS16 code where we
+   have no assembly alternative available and want to avoid the __sync_*
+   builtins if at all possible.  */
+
+#define USE_ATOMIC_COMPILER_BUILTINS 1
+
+/* Compare and exchange.
+   For all "bool" routines, we return FALSE if exchange succesful.  */
+
+# define __arch_compare_and_exchange_bool_8_int(mem, newval, oldval, model) \
+  (abort (), 0)
+
+# define __arch_compare_and_exchange_bool_16_int(mem, newval, oldval, model) \
+  (abort (), 0)
+
+# define __arch_compare_and_exchange_bool_32_int(mem, newval, oldval, model) \
+  ({									\
+    typeof (*mem) __oldval = (oldval);					\
+    !__atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0,	\
+				  model, __ATOMIC_RELAXED);		\
+  })
+
+# define __arch_compare_and_exchange_val_8_int(mem, newval, oldval, model) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_compare_and_exchange_val_16_int(mem, newval, oldval, model) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_compare_and_exchange_val_32_int(mem, newval, oldval, model) \
+  ({									\
+    typeof (*mem) __oldval = (oldval);					\
+    __atomic_compare_exchange_n (mem, (void *) &__oldval, newval, 0,	\
+				 model, __ATOMIC_RELAXED);		\
+    __oldval;								\
+  })
+
+# if _MIPS_SIM == _ABIO32
+  /* We can't do an atomic 64-bit operation in O32.  */
+#  define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
+  (abort (), 0)
+#  define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
+  (abort (), (typeof(*mem)) 0)
+# else
+#  define __arch_compare_and_exchange_bool_64_int(mem, newval, oldval, model) \
+  __arch_compare_and_exchange_bool_32_int (mem, newval, oldval, model)
+#  define __arch_compare_and_exchange_val_64_int(mem, newval, oldval, model) \
+  __arch_compare_and_exchange_val_32_int (mem, newval, oldval, model)
+# endif
+
+/* Compare and exchange with "acquire" semantics, ie barrier after.  */
+
+# define atomic_compare_and_exchange_bool_acq(mem, new, old)	\
+  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int,	\
+			mem, new, old, __ATOMIC_ACQUIRE)
+
+# define atomic_compare_and_exchange_val_acq(mem, new, old)	\
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int,	\
+		       mem, new, old, __ATOMIC_ACQUIRE)
+
+/* Compare and exchange with "release" semantics, ie barrier before.  */
+
+# define atomic_compare_and_exchange_bool_rel(mem, new, old)	\
+  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int,	\
+			mem, new, old, __ATOMIC_RELEASE)
+
+# define atomic_compare_and_exchange_val_rel(mem, new, old)	 \
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int,    \
+                       mem, new, old, __ATOMIC_RELEASE)
+
+
+/* Atomic exchange (without compare).  */
+
+# define __arch_exchange_8_int(mem, newval, model)	\
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_16_int(mem, newval, model)	\
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_32_int(mem, newval, model)	\
+  __atomic_exchange_n (mem, newval, model)
+
+# if _MIPS_SIM == _ABIO32
+/* We can't do an atomic 64-bit operation in O32.  */
+#  define __arch_exchange_64_int(mem, newval, model)	\
+  (abort (), (typeof(*mem)) 0)
+# else
+#  define __arch_exchange_64_int(mem, newval, model)	\
+  __atomic_exchange_n (mem, newval, model)
+# endif
+
+# define atomic_exchange_acq(mem, value)				\
+  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_ACQUIRE)
+
+# define atomic_exchange_rel(mem, value)				\
+  __atomic_val_bysize (__arch_exchange, int, mem, value, __ATOMIC_RELEASE)
+
+
+/* Atomically add value and return the previous (unincremented) value.  */
+
+# define __arch_exchange_and_add_8_int(mem, value, model)	\
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_and_add_16_int(mem, value, model)	\
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_and_add_32_int(mem, value, model)	\
+  __atomic_fetch_add (mem, value, model)
+
+# if _MIPS_SIM == _ABIO32
+/* We can't do an atomic 64-bit operation in O32.  */
+#  define __arch_exchange_and_add_64_int(mem, value, model)	\
+  (abort (), (typeof(*mem)) 0)
+# else
+#  define __arch_exchange_and_add_64_int(mem, value, model)	\
+  __atomic_fetch_add (mem, value, model)
+# endif
+
+# define atomic_exchange_and_add_acq(mem, value)			\
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
+		       __ATOMIC_ACQUIRE)
+
+# define atomic_exchange_and_add_rel(mem, value)			\
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
+		       __ATOMIC_RELEASE)
+
+#elif defined __mips16 /* !__GNUC_PREREQ (4, 7) */
+/* This implementation using __sync* builtins will be removed once glibc
+   requires GCC 4.7 or later to build.  */
+
+# define atomic_compare_and_exchange_val_acq(mem, newval, oldval)	\
+  __sync_val_compare_and_swap ((mem), (oldval), (newval))
+# define atomic_compare_and_exchange_bool_acq(mem, newval, oldval)	\
+  (!__sync_bool_compare_and_swap ((mem), (oldval), (newval)))
+
+# define atomic_exchange_acq(mem, newval)				\
+  __sync_lock_test_and_set ((mem), (newval))
+
+# define atomic_exchange_and_add(mem, val)				\
+  __sync_fetch_and_add ((mem), (val))
+
+# define atomic_bit_test_set(mem, bit)					\
+  ({ __typeof (bit) __bit = (bit);					\
+     (__sync_fetch_and_or ((mem), 1 << (__bit)) & (1 << (__bit))); })
+
+# define atomic_and(mem, mask) (void) __sync_fetch_and_and ((mem), (mask))
+# define atomic_and_val(mem, mask) __sync_fetch_and_and ((mem), (mask))
+
+# define atomic_or(mem, mask) (void) __sync_fetch_and_or ((mem), (mask))
+# define atomic_or_val(mem, mask) __sync_fetch_and_or ((mem), (mask))
+
+#else /* !__mips16 && !__GNUC_PREREQ (4, 8) */
+/* This implementation using inline assembly will be removed once glibc
+   requires GCC 4.8 or later to build.  */
+
+#define USE_ATOMIC_COMPILER_BUILTINS 0
+
+/* Compare and exchange.  For all of the "xxx" routines, we expect a
+   "__prev" and a "__cmp" variable to be provided by the enclosing scope,
+   in which values are returned.  */
+
+# define __arch_compare_and_exchange_xxx_8_int(mem, newval, oldval, rel, acq) \
+  (abort (), __prev = 0, __cmp = 0, (void) __cmp)
+
+# define __arch_compare_and_exchange_xxx_16_int(mem, newval, oldval, rel, acq) \
+  (abort (), __prev = 0, __cmp = 0, (void) __cmp)
+
+# define __arch_compare_and_exchange_xxx_32_int(mem, newval, oldval, rel, acq) \
+     __asm__ __volatile__ (						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\t"								      \
+     "ll	%0,%5\n\t"						      \
+     "move	%1,$0\n\t"						      \
+     "bne	%0,%3,2f\n\t"						      \
+     "move	%1,%4\n\t"						      \
+     "sc	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (oldval), "r" (newval), "m" (*mem)			      \
+	      : "memory")
+
+# if _MIPS_SIM == _ABIO32
+/* We can't do an atomic 64-bit operation in O32.  */
+# define __arch_compare_and_exchange_xxx_64_int(mem, newval, oldval, rel, acq) \
+  (abort (), __prev = 0, __cmp = 0, (void) __cmp)
+# else
+# define __arch_compare_and_exchange_xxx_64_int(mem, newval, oldval, rel, acq) \
+     __asm__ __volatile__ ("\n"						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\t"								      \
+     "lld	%0,%5\n\t"						      \
+     "move	%1,$0\n\t"						      \
+     "bne	%0,%3,2f\n\t"						      \
+     "move	%1,%4\n\t"						      \
+     "scd	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (oldval), "r" (newval), "m" (*mem)			      \
+	      : "memory")
+# endif
+
+/* For all "bool" routines, we return FALSE if exchange succesful.  */
+
+# define __arch_compare_and_exchange_bool_8_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev __attribute__ ((unused)); int __cmp;		\
+   __arch_compare_and_exchange_xxx_8_int(mem, new, old, rel, acq);	\
+   !__cmp; })
+
+# define __arch_compare_and_exchange_bool_16_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev __attribute__ ((unused)); int __cmp;		\
+   __arch_compare_and_exchange_xxx_16_int(mem, new, old, rel, acq);	\
+   !__cmp; })
+
+# define __arch_compare_and_exchange_bool_32_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev __attribute__ ((unused)); int __cmp;		\
+   __arch_compare_and_exchange_xxx_32_int(mem, new, old, rel, acq);	\
+   !__cmp; })
+
+# define __arch_compare_and_exchange_bool_64_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev __attribute__ ((unused)); int __cmp;		\
+   __arch_compare_and_exchange_xxx_64_int(mem, new, old, rel, acq);	\
+   !__cmp; })
+
+/* For all "val" routines, return the old value whether exchange
+   successful or not.  */
+
+# define __arch_compare_and_exchange_val_8_int(mem, new, old, rel, acq)	\
+({ typeof (*mem) __prev; int __cmp;					\
+   __arch_compare_and_exchange_xxx_8_int(mem, new, old, rel, acq);	\
+   (typeof (*mem))__prev; })
+
+# define __arch_compare_and_exchange_val_16_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					\
+   __arch_compare_and_exchange_xxx_16_int(mem, new, old, rel, acq);	\
+   (typeof (*mem))__prev; })
+
+# define __arch_compare_and_exchange_val_32_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					\
+   __arch_compare_and_exchange_xxx_32_int(mem, new, old, rel, acq);	\
+   (typeof (*mem))__prev; })
+
+# define __arch_compare_and_exchange_val_64_int(mem, new, old, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					\
+   __arch_compare_and_exchange_xxx_64_int(mem, new, old, rel, acq);	\
+   (typeof (*mem))__prev; })
+
+/* Compare and exchange with "acquire" semantics, ie barrier after.  */
+
+# define atomic_compare_and_exchange_bool_acq(mem, new, old)	\
+  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int,	\
+		        mem, new, old, "", MIPS_SYNC_STR)
+
+# define atomic_compare_and_exchange_val_acq(mem, new, old)	\
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int,	\
+		       mem, new, old, "", MIPS_SYNC_STR)
+
+/* Compare and exchange with "release" semantics, ie barrier before.  */
+
+# define atomic_compare_and_exchange_bool_rel(mem, new, old)	\
+  __atomic_bool_bysize (__arch_compare_and_exchange_bool, int,	\
+		        mem, new, old, MIPS_SYNC_STR, "")
+
+# define atomic_compare_and_exchange_val_rel(mem, new, old)	\
+  __atomic_val_bysize (__arch_compare_and_exchange_val, int,	\
+		       mem, new, old, MIPS_SYNC_STR, "")
+
+
+
+/* Atomic exchange (without compare).  */
+
+# define __arch_exchange_xxx_8_int(mem, newval, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_xxx_16_int(mem, newval, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_xxx_32_int(mem, newval, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					      \
+     __asm__ __volatile__ ("\n"						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\t"								      \
+     "ll	%0,%4\n\t"						      \
+     "move	%1,%3\n\t"						      \
+     "sc	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (newval), "m" (*mem)				      \
+	      : "memory");						      \
+  __prev; })
+
+# if _MIPS_SIM == _ABIO32
+/* We can't do an atomic 64-bit operation in O32.  */
+#  define __arch_exchange_xxx_64_int(mem, newval, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+# else
+#  define __arch_exchange_xxx_64_int(mem, newval, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					      \
+     __asm__ __volatile__ ("\n"						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\n"								      \
+     "lld	%0,%4\n\t"						      \
+     "move	%1,%3\n\t"						      \
+     "scd	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (newval), "m" (*mem)				      \
+	      : "memory");						      \
+  __prev; })
+# endif
+
+# define atomic_exchange_acq(mem, value) \
+  __atomic_val_bysize (__arch_exchange_xxx, int, mem, value, "", MIPS_SYNC_STR)
+
+# define atomic_exchange_rel(mem, value) \
+  __atomic_val_bysize (__arch_exchange_xxx, int, mem, value, MIPS_SYNC_STR, "")
+
+
+/* Atomically add value and return the previous (unincremented) value.  */
+
+# define __arch_exchange_and_add_8_int(mem, newval, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_and_add_16_int(mem, newval, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+
+# define __arch_exchange_and_add_32_int(mem, value, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					      \
+     __asm__ __volatile__ ("\n"						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\t"								      \
+     "ll	%0,%4\n\t"						      \
+     "addu	%1,%0,%3\n\t"						      \
+     "sc	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (value), "m" (*mem)					      \
+	      : "memory");						      \
+  __prev; })
+
+# if _MIPS_SIM == _ABIO32
+/* We can't do an atomic 64-bit operation in O32.  */
+#  define __arch_exchange_and_add_64_int(mem, value, rel, acq) \
+  (abort (), (typeof(*mem)) 0)
+# else
+#  define __arch_exchange_and_add_64_int(mem, value, rel, acq) \
+({ typeof (*mem) __prev; int __cmp;					      \
+     __asm__ __volatile__ (						      \
+     ".set	push\n\t"						      \
+     MIPS_PUSH_MIPS2							      \
+     rel	"\n"							      \
+     "1:\t"								      \
+     "lld	%0,%4\n\t"						      \
+     "daddu	%1,%0,%3\n\t"						      \
+     "scd	%1,%2\n\t"						      \
+     R10K_BEQZ_INSN"	%1,1b\n"					      \
+     acq	"\n\t"							      \
+     ".set	pop\n"							      \
+     "2:\n\t"								      \
+	      : "=&r" (__prev), "=&r" (__cmp), "=m" (*mem)		      \
+	      : "r" (value), "m" (*mem)					      \
+	      : "memory");						      \
+  __prev; })
+# endif
+
+# define atomic_exchange_and_add_acq(mem, value)			\
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
+		       "", MIPS_SYNC_STR)
+
+# define atomic_exchange_and_add_rel(mem, value)			\
+  __atomic_val_bysize (__arch_exchange_and_add, int, mem, value,	\
+		       MIPS_SYNC_STR, "")
+
+#endif /* !__mips16 && !__GNUC_PREREQ (4, 8) */
+
+/* TODO: More atomic operations could be implemented efficiently; only the
+   basic requirements are done.  */
+
+#ifdef __mips16
+# define atomic_full_barrier() __sync_synchronize ()
+
+#else /* !__mips16 */
+# define atomic_full_barrier() \
+  __asm__ __volatile__ (".set push\n\t"					      \
+			MIPS_PUSH_MIPS2					      \
+			MIPS_SYNC_STR "\n\t"				      \
+			".set pop" : : : "memory")
+#endif /* !__mips16 */
+
+#endif /* atomic-machine.h */