/* Copyright (C) 2002, 2003 Free Software Foundation, Inc. This file is part of the GNU C Library. Contributed by Ulrich Drepper , 2002. 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. */ #ifndef UP # define LOCK lock #else # define LOCK #endif #define SYS_futex 202 #define FUTEX_WAKE 1 .comm __fork_generation, 4, 4 .text .globl __pthread_once .type __pthread_once,@function .align 16 __pthread_once: .LSTARTCODE: testl $2, (%rdi) jz 1f xorl %eax, %eax retq /* Preserve the function pointer. */ 1: pushq %rsi .Lpush_rsi: xorq %r10, %r10 /* Not yet initialized or initialization in progress. Get the fork generation counter now. */ 6: movl (%rdi), %eax 5: movl %eax, %edx testl $2, %eax jnz 4f andl $3, %edx orl __fork_generation(%rip), %edx orl $1, %edx LOCK cmpxchgl %edx, (%rdi) jnz 5b /* Check whether another thread already runs the initializer. */ testl $1, %eax jz 3f /* No -> do it. */ /* Check whether the initializer execution was interrupted by a fork. */ xorl %edx, %eax testl $0xfffffffc, %eax jnz 3f /* Different for generation -> run initializer. */ /* Somebody else got here first. Wait. */ movq %r10, %rsi /* movq $FUTEX_WAIT, %rsi */ movq $SYS_futex, %rax syscall jmp 6b /* Preserve the pointer to the control variable. */ 3: pushq %rdi .Lpush_rdi: .LcleanupSTART: callq *8(%rsp) .LcleanupEND: /* Get the control variable address back. */ popq %rdi .Lpop_rdi: /* Sucessful run of the initializer. Signal that we are done. */ LOCK incl (%rdi) /* Wake up all other threads. */ movl $0x7fffffff, %edx movl $FUTEX_WAKE, %esi movq $SYS_futex, %rax syscall 4: addq $8, %rsp .Ladd: xorq %rax, %rax retq .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 16 clear_once_control: movq (%rsp), %rdi movq %rax, %r8 movl $0, (%rdi) movl $0x7fffffff, %edx movq $FUTEX_WAKE, %rsi movq $SYS_futex, %rax syscall movq %r8, %rdi .LcallUR: call _Unwind_Resume@PLT hlt .LENDCODE: .size clear_once_control,.-clear_once_control .section .gcc_except_table,"a",@progbits .LexceptSTART: .byte 0xff # @LPStart format (omit) .byte 0xff # @TType format (omit) .byte 0x01 # call-site format # DW_EH_PE_uleb128 .uleb128 .Lcstend-.Lcstbegin .Lcstbegin: .uleb128 .LcleanupSTART-.LSTARTCODE .uleb128 .LcleanupEND-.LcleanupSTART .uleb128 clear_once_control-.LSTARTCODE .uleb128 0 .uleb128 .LcallUR-.LSTARTCODE .uleb128 .LENDCODE-.LcallUR .uleb128 0 .uleb128 0 .Lcstend: .section .eh_frame,"a",@progbits .LSTARTFRAME: .long .LENDCIE-.LSTARTCIE # Length of the CIE. .LSTARTCIE: .long 0 # CIE ID. .byte 1 # Version number. #ifdef SHARED .string "zPLR" # NUL-terminated augmentation # string. #else .string "zPL" # NUL-terminated augmentation # string. #endif .uleb128 1 # Code alignment factor. .sleb128 -8 # Data alignment factor. .byte 16 # Return address register # column. #ifdef SHARED .uleb128 7 # Augmentation value length. .byte 0x9b # Personality: DW_EH_PE_pcrel # + DW_EH_PE_sdata4 # + DW_EH_PE_indirect .long DW.ref.__gcc_personality_v0-. .byte 0x1b # LSDA Encoding: DW_EH_PE_pcrel # + DW_EH_PE_sdata4. .byte 0x1b # FDE Encoding: DW_EH_PE_pcrel # + DW_EH_PE_sdata4. #else .uleb128 10 # Augmentation value length. .byte 0x0 # Personality: absolute .quad __gcc_personality_v0 .byte 0x0 # LSDA Encoding: absolute #endif .byte 0x0c # DW_CFA_def_cfa .uleb128 7 .uleb128 8 .byte 0x90 # DW_CFA_offset, column 0x10 .uleb128 1 .align 8 .LENDCIE: .long .LENDFDE-.LSTARTFDE # Length of the FDE. .LSTARTFDE: .long .LSTARTFDE-.LSTARTFRAME # CIE pointer. #ifdef SHARED .long .LSTARTCODE-. # PC-relative start address # of the code. .long .LENDCODE-.LSTARTCODE # Length of the code. .uleb128 4 # Augmentation size .long .LexceptSTART-. #else .quad .LSTARTCODE # Start address of the code. .quad .LENDCODE-.LSTARTCODE # Length of the code. .uleb128 8 # Augmentation size .quad .LexceptSTART #endif .byte 4 # DW_CFA_advance_loc4 .long .Lpush_rsi-.LSTARTCODE .byte 14 # DW_CFA_def_cfa_offset .uleb128 16 .byte 4 # DW_CFA_advance_loc4 .long .Lpush_rdi-.Lpush_rsi .byte 14 # DW_CFA_def_cfa_offset .uleb128 24 .byte 4 # DW_CFA_advance_loc4 .long .Lpop_rdi-.Lpush_rdi .byte 14 # DW_CFA_def_cfa_offset .uleb128 16 .byte 4 # DW_CFA_advance_loc4 .long .Ladd-.Lpop_rdi .byte 14 # DW_CFA_def_cfa_offset .uleb128 8 .byte 4 # DW_CFA_advance_loc4 .long clear_once_control-.Ladd .byte 14 # DW_CFA_def_cfa_offset .uleb128 24 #if 0 .byte 4 # DW_CFA_advance_loc4 .long .Lpop_rdi2-clear_once_control .byte 14 # DW_CFA_def_cfa_offset .uleb128 16 #endif .align 8 .LENDFDE: #ifdef SHARED .hidden DW.ref.__gcc_personality_v0 .weak DW.ref.__gcc_personality_v0 .section .gnu.linkonce.d.DW.ref.__gcc_personality_v0,"aw",@progbits .align 8 .type DW.ref.__gcc_personality_v0, @object .size DW.ref.__gcc_personality_v0, 8 DW.ref.__gcc_personality_v0: .quad __gcc_personality_v0 #endif