diff options
Diffstat (limited to 'ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h')
| -rw-r--r-- | ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h | 60 |
1 files changed, 13 insertions, 47 deletions
diff --git a/ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h b/ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h index c9ad50d135..3374153867 100644 --- a/ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h +++ b/ports/sysdeps/unix/sysv/linux/arm/nptl/bits/atomic.h @@ -1,4 +1,5 @@ -/* Copyright (C) 2002-2012 Free Software Foundation, Inc. +/* Atomic operations. ARM/Linux version. + Copyright (C) 2002-2012 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 @@ -15,41 +16,17 @@ License along with the GNU C Library. If not, see <http://www.gnu.org/licenses/>. */ -#include <stdint.h> -#include <sysdep.h> - - -typedef int8_t atomic8_t; -typedef uint8_t uatomic8_t; -typedef int_fast8_t atomic_fast8_t; -typedef uint_fast8_t uatomic_fast8_t; - -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 intptr_t atomicptr_t; -typedef uintptr_t uatomicptr_t; -typedef intmax_t atomic_max_t; -typedef uintmax_t uatomic_max_t; - -void __arm_link_error (void); - -/* Use the atomic builtins provided by GCC in case the backend provides - a pattern to do this efficiently. */ - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 -#define atomic_full_barrier() __sync_synchronize () -#elif defined __thumb2__ -#define atomic_full_barrier() \ +/* If the compiler doesn't provide a primitive, we'll use this macro + to get assistance from the kernel. */ +#ifdef __thumb2__ +# define __arm_assisted_full_barrier() \ __asm__ __volatile__ \ ("movw\tip, #0x0fa0\n\t" \ "movt\tip, #0xffff\n\t" \ "blx\tip" \ : : : "ip", "lr", "cc", "memory"); #else -#define atomic_full_barrier() \ +# define __arm_assisted_full_barrier() \ __asm__ __volatile__ \ ("mov\tip, #0xffff0fff\n\t" \ "mov\tlr, pc\n\t" \ @@ -60,19 +37,9 @@ void __arm_link_error (void); /* Atomic compare and exchange. This sequence relies on the kernel to provide a compare and exchange operation which is atomic on the current architecture, either via cleverness on pre-ARMv6 or via - ldrex / strex on ARMv6. */ - -#define __arch_compare_and_exchange_val_8_acq(mem, newval, oldval) \ - ({ __arm_link_error (); oldval; }) - -#define __arch_compare_and_exchange_val_16_acq(mem, newval, oldval) \ - ({ __arm_link_error (); oldval; }) - -#ifdef __GCC_HAVE_SYNC_COMPARE_AND_SWAP_4 -#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \ - __sync_val_compare_and_swap ((mem), (oldval), (newval)) + ldrex / strex on ARMv6. -/* It doesn't matter what register is used for a_oldval2, but we must + It doesn't matter what register is used for a_oldval2, but we must specify one to work around GCC PR rtl-optimization/21223. Otherwise it may cause a_oldval or a_tmp to be moved to a different register. @@ -81,10 +48,10 @@ void __arm_link_error (void); form *PTR and PTR has a 'volatile ... *' type, then __typeof (*PTR) has a 'volatile ...' type and this triggers -Wvolatile-register-var to complain about 'register volatile ... asm ("reg")'. */ -#elif defined __thumb2__ +#ifdef __thumb2__ /* Thumb-2 has ldrex/strex. However it does not have barrier instructions, so we still need to use the kernel helper. */ -#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \ +# define __arm_assisted_compare_and_exchange_val_32_acq(mem, newval, oldval) \ ({ union { __typeof (oldval) a; uint32_t v; } oldval_arg = { .a = (oldval) };\ union { __typeof (newval) a; uint32_t v; } newval_arg = { .a = (newval) };\ register uint32_t a_oldval asm ("r0"); \ @@ -109,7 +76,7 @@ void __arm_link_error (void); : "ip", "lr", "cc", "memory"); \ (__typeof (oldval)) a_tmp; }) #else -#define __arch_compare_and_exchange_val_32_acq(mem, newval, oldval) \ +# define __arm_assisted_compare_and_exchange_val_32_acq(mem, newval, oldval) \ ({ union { __typeof (oldval) a; uint32_t v; } oldval_arg = { .a = (oldval) };\ union { __typeof (newval) a; uint32_t v; } newval_arg = { .a = (newval) };\ register uint32_t a_oldval asm ("r0"); \ @@ -135,5 +102,4 @@ void __arm_link_error (void); (__typeof (oldval)) a_tmp; }) #endif -#define __arch_compare_and_exchange_val_64_acq(mem, newval, oldval) \ - ({ __arm_link_error (); oldval; }) +#include <sysdeps/arm/bits/atomic.h> |