diff options
Diffstat (limited to 'nptl/sysdeps/unix/sysv/linux/sh/pthread_once.S')
| -rw-r--r-- | nptl/sysdeps/unix/sysv/linux/sh/pthread_once.S | 197 |
1 files changed, 197 insertions, 0 deletions
diff --git a/nptl/sysdeps/unix/sysv/linux/sh/pthread_once.S b/nptl/sysdeps/unix/sysv/linux/sh/pthread_once.S new file mode 100644 index 0000000000..c17701cffc --- /dev/null +++ b/nptl/sysdeps/unix/sysv/linux/sh/pthread_once.S @@ -0,0 +1,197 @@ +/* Copyright (C) 2003 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, write to the Free + Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA + 02111-1307 USA. */ + +#include <sysdep.h> +#include "lowlevel-atomic.h" + +#define SYS_futex 240 +#define FUTEX_WAIT 0 +#define FUTEX_WAKE 1 + + .comm __fork_generation, 4, 4 + + .text + .globl __pthread_once + .type __pthread_once,@function + .align 5 +__pthread_once: + mov.l @r4, r0 + tst #2, r0 + bt 1f + rts + mov #0, r0 + +1: + mov.l r12, @-r15 + mov.l r9, @-r15 + mov.l r8, @-r15 + sts.l pr, @-r15 + mov r5, r8 + + /* Not yet initialized or initialization in progress. + Get the fork generation counter now. */ +6: + mov.l @r4, r1 +#ifdef PIC + mova .Lgot, r0 + mov.l .Lgot, r12 + add r0, r12 +#endif + +5: + mov r1, r0 + + tst #2, r0 + bf 4f + + and #3, r0 + mov.l .Lfgen, r2 +#ifdef PIC + add r12, r2 +#endif + mov.l @r2, r3 + or r3, r0 + or #1, r0 + mov r0, r3 + mov r1, r5 + + CMPXCHG (r5, @r4, r3, r2) + bf 5b + + /* Check whether another thread already runs the initializer. */ + mov r2, r0 + tst #1, r0 + bt 3f /* No -> do it. */ + + /* Check whether the initializer execution was interrupted + by a fork. */ + xor r3, r0 + mov #-4, r1 /* -4 = 0xfffffffc */ + tst r1, r0 + bf 3f /* Different for generation -> run initializer. */ + + /* Somebody else got here first. Wait. */ + mov #FUTEX_WAIT, r5 + mov r3, r6 + mov #0, r7 + mov #SYS_futex, r3 + extu.b r3, r3 + trapa #0x14 + SYSCALL_INST_PAD + bra 6b + nop + + .align 2 +#ifdef PIC +.Lgot: + .long _GLOBAL_OFFSET_TABLE_ +.Lfgen: + .long __fork_generation@GOTOFF +#else +.Lfgen: + .long __fork_generation +#endif + +3: + /* Call the initializer function after setting up the + cancellation handler. */ + /* Allocate a _pthread_cleanup_buffer on stack. */ + add #-16, r15 + + /* Push the cleanup handler. */ + mov r4, r9 + mov r15, r4 + mov.l .Lconce, r5 +#ifdef PIC + add r12, r5 +#endif + mov.l .Lcpush, r1 + bsrf r1 + mov r3, r6 +.Lcpush0: + jsr @r8 + nop + + /* Pop the cleanup handler. */ + mov r15, r4 + mov.l .Lcpop, r1 + bsrf r1 + mov #0, r5 +.Lcpop0: + add #16, r15 + + /* Sucessful run of the initializer. Signal that we are done. */ + INC (@r9, r2) + /* Wake up all other threads. */ + mov r9, r4 + mov #FUTEX_WAKE, r5 + mov #-1, r6 + shlr r6 /* r6 = 0x7fffffff */ + mov #0, r7 + mov #SYS_futex, r3 + extu.b r3, r3 + trapa #0x14 + SYSCALL_INST_PAD + +4: + lds.l @r15+, pr + mov.l @r15+, r8 + mov.l @r15+, r9 + mov.l @r15+, r12 + rts + mov #0, r0 + + .align 2 +.Lconce: +#ifdef PIC + .long clear_once_control@GOTOFF +#else + .long clear_once_control +#endif +.Lcpush: + .long __pthread_cleanup_push - .Lcpush0 /* Note: no @PLT. */ +.Lcpop: + .long __pthread_cleanup_pop - .Lcpop0 /* Note: no @PLT. */ + + .size __pthread_once,.-__pthread_once + + .globl __pthread_once_internal +__pthread_once_internal = __pthread_once + + .globl pthread_once +pthread_once = __pthread_once + + + .type clear_once_control,@function + .align 5 +clear_once_control: + mov #0, r0 + mov.l r0, @r4 + + mov #FUTEX_WAKE, r5 + mov #-1, r6 + shlr r6 /* r6 = 0x7fffffff */ + mov #0, r7 + mov #SYS_futex, r3 + extu.b r3, r3 + trapa #0x14 + SYSCALL_INST_PAD + + rts + nop + .size clear_once_control,.-clear_once_control |