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/*
* June 27, 2001 Manuel Novoa III
*
* This is a heavily modified version of gcc's output for the syscall5 macro.
* The idea (originally from dietlibc) is that all syscall functions simply
* set the syscall number in %al (since <= 255) and then jump here. All the
* common work is done by __uClibc_syscall, saving a fair amount of generated
* code where a number of syscalls are used. The (potential) cost is some
* unnecessary pushes, pops, and movs but the execution time penalty should
* be relatively small compared to the cost of the syscall itself.
*
* WARNING: If the startup code for uClibc changes, I suppose it is possible
* that this code might try to access memory under the bottom of
* the stack.
* WARNING: This will need to be modified if the number of syscalls ever
* exceeds 255. So will the associated syscall macros.
*/
.text
.align 4
.globl __uClibc_syscall
.type __uClibc_syscall,@function
__uClibc_syscall:
pushl %edi
pushl %esi
pushl %ebx
and $0xff,%eax
movl 16(%esp),%ebx
movl 20(%esp),%ecx
movl 24(%esp),%edx
movl 28(%esp),%esi
movl 32(%esp),%edi
#APP
int $0x80
#NO_APP
cmpl $-4095,%eax
jbe .Ldone
#ifdef PIC
call Lhere
Lhere:
popl %ebx
addl $_GLOBAL_OFFSET_TABLE_+[.-Lhere],%ebx
negl %eax
movl %eax,%ecx
#ifdef _LIBC_REENTRANT
call __errno_location@PLT
#else
movl errno@GOT(%ebx),%eax
#endif /* _LIBC_REENTRANT */
movl %ecx,(%eax)
#else
negl %eax
#ifdef _LIBC_REENTRANT
movl %eax,%ecx
call __errno_location
movl %ecx,(%eax)
#else
movl %eax,errno
#endif /* _LIBC_REENTRANT */
#endif /* PIC */
movl $-1,%eax
.p2align 4,,7
.Ldone:
popl %ebx
popl %esi
popl %edi
ret
.Lsize:
.size __uClibc_syscall,.Lsize-__uClibc_syscall
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