X-Git-Url: http://git.sourceforge.jp/view?p=pf3gnuchains%2Fgcc-fork.git;a=blobdiff_plain;f=libjava%2Fsysdep%2Fi386%2Flocks.h;h=9d130b0f515446c27d83c8673f02499ac4cf7d3b;hp=7b99f0bd7816dd2173f34a21cc2f49465a1a9546;hb=9cecf767f073a1b553c04e7884cc37db12fbe2d0;hpb=3962e00c61cc12efda893d31cbdec381fce6521b diff --git a/libjava/sysdep/i386/locks.h b/libjava/sysdep/i386/locks.h index 7b99f0bd781..9d130b0f515 100644 --- a/libjava/sysdep/i386/locks.h +++ b/libjava/sysdep/i386/locks.h @@ -1,6 +1,6 @@ /* locks.h - Thread synchronization primitives. X86/x86-64 implementation. - Copyright (C) 2002, 2011 Free Software Foundation + Copyright (C) 2002 Free Software Foundation This file is part of libgcj. @@ -23,25 +23,19 @@ compare_and_swap(volatile obj_addr_t *addr, obj_addr_t old, obj_addr_t new_val) { - return __sync_bool_compare_and_swap (addr, old, new_val); -} - -// Ensure that subsequent instructions do not execute on stale -// data that was loaded from memory before the barrier. -// On X86/x86-64, the hardware ensures that reads are properly ordered. -inline static void -read_barrier() -{ -} - -// Ensure that prior stores to memory are completed with respect to other -// processors. -inline static void -write_barrier() -{ - /* x86-64/X86 does not reorder writes. We just need to ensure that - gcc also doesn't. */ - __asm__ __volatile__(" " : : : "memory"); + char result; +#ifdef __x86_64__ + __asm__ __volatile__("lock; cmpxchgq %2, %0; setz %1" + : "=m"(*(addr)), "=q"(result) + : "r" (new_val), "a"(old), "m"(*addr) + : "memory"); +#else + __asm__ __volatile__("lock; cmpxchgl %2, %0; setz %1" + : "=m"(*addr), "=q"(result) + : "r" (new_val), "a"(old), "m"(*addr) + : "memory"); +#endif + return (bool) result; } // Set *addr to new_val with release semantics, i.e. making sure @@ -52,7 +46,7 @@ write_barrier() inline static void release_set(volatile obj_addr_t *addr, obj_addr_t new_val) { - write_barrier (); + __asm__ __volatile__(" " : : : "memory"); *(addr) = new_val; } @@ -66,4 +60,22 @@ compare_and_swap_release(volatile obj_addr_t *addr, { return compare_and_swap(addr, old, new_val); } + +// Ensure that subsequent instructions do not execute on stale +// data that was loaded from memory before the barrier. +// On X86/x86-64, the hardware ensures that reads are properly ordered. +inline static void +read_barrier() +{ +} + +// Ensure that prior stores to memory are completed with respect to other +// processors. +inline static void +write_barrier() +{ + /* x86-64/X86 does not reorder writes. We just need to ensure that + gcc also doesn't. */ + __asm__ __volatile__(" " : : : "memory"); +} #endif