glibc/sysdeps/i386/dl-trampoline.S

186 lines
4.5 KiB
ArmAsm

/* PLT trampolines. i386 version.
Copyright (C) 2004-2015 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, see
<http://www.gnu.org/licenses/>. */
#include <sysdep.h>
.text
.globl _dl_runtime_resolve
.type _dl_runtime_resolve, @function
cfi_startproc
.align 16
_dl_runtime_resolve:
cfi_adjust_cfa_offset (8)
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl 16(%esp), %edx # Copy args pushed by PLT in register. Note
movl 12(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_fixup # Call resolver.
popl %edx # Get register content back.
cfi_adjust_cfa_offset (-4)
movl (%esp), %ecx
movl %eax, (%esp) # Store the function address.
movl 4(%esp), %eax
ret $12 # Jump to function address.
cfi_endproc
.size _dl_runtime_resolve, .-_dl_runtime_resolve
#ifndef PROF
.globl _dl_runtime_profile
.type _dl_runtime_profile, @function
cfi_startproc
.align 16
_dl_runtime_profile:
cfi_adjust_cfa_offset (8)
pushl %esp
cfi_adjust_cfa_offset (4)
addl $8, (%esp) # Account for the pushed PLT data
pushl %ebp
cfi_adjust_cfa_offset (4)
pushl %eax # Preserve registers otherwise clobbered.
cfi_adjust_cfa_offset (4)
pushl %ecx
cfi_adjust_cfa_offset (4)
pushl %edx
cfi_adjust_cfa_offset (4)
movl %esp, %ecx
subl $8, %esp
cfi_adjust_cfa_offset (8)
movl $-1, 4(%esp)
leal 4(%esp), %edx
movl %edx, (%esp)
pushl %ecx # Address of the register structure
cfi_adjust_cfa_offset (4)
movl 40(%esp), %ecx # Load return address
movl 36(%esp), %edx # Copy args pushed by PLT in register. Note
movl 32(%esp), %eax # that `fixup' takes its parameters in regs.
call _dl_profile_fixup # Call resolver.
cfi_adjust_cfa_offset (-8)
movl (%esp), %edx
testl %edx, %edx
jns 1f
popl %edx
cfi_adjust_cfa_offset (-4)
popl %edx # Get register content back.
cfi_adjust_cfa_offset (-4)
movl (%esp), %ecx
movl %eax, (%esp) # Store the function address.
movl 4(%esp), %eax
ret $20 # Jump to function address.
/*
+32 return address
+28 PLT1
+24 PLT2
+20 %esp
+16 %ebp
+12 %eax
+8 %ecx
+4 %edx
%esp free
*/
cfi_adjust_cfa_offset (8)
1: movl %ebx, (%esp)
cfi_rel_offset (ebx, 0)
movl %edx, %ebx # This is the frame buffer size
pushl %edi
cfi_adjust_cfa_offset (4)
cfi_rel_offset (edi, 0)
pushl %esi
cfi_adjust_cfa_offset (4)
cfi_rel_offset (esi, 0)
leal 44(%esp), %esi
movl %ebx, %ecx
orl $4, %ebx # Increase frame size if necessary to align
# stack for the function call
andl $~3, %ebx
movl %esp, %edi
subl %ebx, %edi
movl %esp, %ebx
cfi_def_cfa_register (ebx)
movl %edi, %esp
shrl $2, %ecx
rep
movsl
movl (%ebx), %esi
cfi_restore (esi)
movl 4(%ebx), %edi
cfi_restore (edi)
/*
%ebx+40 return address
%ebx+36 PLT1
%ebx+32 PLT2
%ebx+28 %esp
%ebx+24 %ebp
%ebx+20 %eax
%ebx+16 %ecx
%ebx+12 %edx
%ebx+8 %ebx
%ebx+4 free
%ebx free
%esp copied stack frame
*/
movl %eax, (%ebx)
movl 12(%ebx), %edx
movl 16(%ebx), %ecx
movl 20(%ebx), %eax
call *(%ebx)
movl %ebx, %esp
cfi_def_cfa_register (esp)
movl 8(%esp), %ebx
cfi_restore (ebx)
/*
+40 return address
+36 PLT1
+32 PLT2
+28 %esp
+24 %ebp
+20 %eax
+16 %ecx
+12 %edx
+8 free
+4 free
%esp free
*/
subl $20, %esp
cfi_adjust_cfa_offset (20)
movl %eax, (%esp)
movl %edx, 4(%esp)
fstpt 8(%esp)
fstpt 20(%esp)
pushl %esp
cfi_adjust_cfa_offset (4)
leal 36(%esp), %ecx
movl 56(%esp), %eax
movl 60(%esp), %edx
call _dl_call_pltexit
movl (%esp), %eax
movl 4(%esp), %edx
fldt 20(%esp)
fldt 8(%esp)
addl $60, %esp
cfi_adjust_cfa_offset (-60)
ret
cfi_endproc
.size _dl_runtime_profile, .-_dl_runtime_profile
#endif