011e111d29
The use of the .hidden directive to avoid going via the PLT for __set_errno had the side-effect of actually making __set_errno hidden (which is odd because assembler directives don't usually affect symbols defined in a different file --- you can't even create a weak reference to a symbol that's defined in a different file). This change switches the system call stubs over to a new always-hidden __set_errno_internal and has a visible __set_errno on LP32 just for binary compatibility with old NDK apps. (cherry-pick of 7efad83d430f4d824f2aaa75edea5106f6ff8aae.) Bug: 17423135 Change-Id: I6b6d7a05dda85f923d22e5ffd169a91e23499b7b
77 lines
2.8 KiB
ArmAsm
77 lines
2.8 KiB
ArmAsm
/*
|
|
* Copyright (C) 2013 The Android Open Source Project
|
|
* All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* * Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* * Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in
|
|
* the documentation and/or other materials provided with the
|
|
* distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
|
|
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
|
|
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
|
|
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
|
|
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
|
|
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
|
|
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
|
|
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
|
|
* SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <private/bionic_asm.h>
|
|
|
|
// pid_t __bionic_clone(int flags, void* child_stack, pid_t* parent_tid, void* tls, pid_t* child_tid, int (*fn)(void*), void* arg);
|
|
ENTRY(__bionic_clone)
|
|
# Copy 'fn' and 'arg' onto the child stack.
|
|
movq %r9, -16(%rsi) # fn
|
|
movq 8(%rsp), %rax # Read 'arg'.
|
|
movq %rax, -8(%rsi) # Write 'arg'.
|
|
|
|
subq $16, %rsi
|
|
|
|
# Translate to the kernel calling convention and swap the 'tls' and 'child_tid' arguments.
|
|
# They're flipped for x86-64 compared to all our other architectures and __bionic_clone.
|
|
movq %r8, %r10
|
|
movq %rcx, %r8
|
|
|
|
# Make the system call.
|
|
movl $__NR_clone, %eax
|
|
syscall
|
|
|
|
# Check result.
|
|
testq %rax, %rax
|
|
jz .L_bc_child
|
|
jg .L_bc_parent
|
|
|
|
# An error occurred, set errno and return -1.
|
|
negl %eax
|
|
movl %eax, %edi
|
|
call __set_errno_internal
|
|
ret
|
|
|
|
.L_bc_child:
|
|
# We don't want anyone to unwind past this point.
|
|
.cfi_undefined %rip
|
|
.cfi_undefined %rbp
|
|
|
|
# We're in the child now, so call __start_thread
|
|
# with the arguments from the child stack moved into
|
|
# the appropriate registers.
|
|
popq %rdi # fn
|
|
popq %rsi # arg
|
|
call __start_thread
|
|
hlt
|
|
|
|
.L_bc_parent:
|
|
# We're the parent; nothing to do.
|
|
ret
|
|
END(__bionic_clone)
|
|
.hidden __bionic_clone
|