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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 as the first argument, then set the syscall arguments as

 * the next up-to-five arguments, and then jump here.  All the common work is

 * done by syscall(), saving a fair amount of generated code when 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.

 *

 * July 24, 2002

 *

 * Modified by Erik Andersen to take all function parameters from off the stack

 * like a proper function and eliminates the old 255 syscall number limit.  So

 * now we can just call this as a function as syscall() per the function

 * prototype in unistd.h, so to call _exit(42) you can just call.

 *         syscall(__NR_exit, 42);

 * and things will just work.

 */

.text

        .align 4

.globl syscall

        .type    syscall,@function

syscall:

        pushl %edi

        pushl %esi

        pushl %ebx

        movl  36(%esp),%edi;    /* Load the 5 syscall argument registers */

        movl  32(%esp),%esi;

        movl  28(%esp),%edx;

        movl  24(%esp),%ecx;

        movl  20(%esp),%ebx;

        movl  16(%esp),%eax     /* Load syscall number into %eax.  */

#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 __UCLIBC_HAS_THREADS__

        call __errno_location@PLT

#else

        movl errno@GOT(%ebx),%eax

#endif /* __UCLIBC_HAS_THREADS__ */

        movl %ecx,(%eax)

#else

        negl %eax

#ifdef __UCLIBC_HAS_THREADS__

        movl %eax,%ecx

        call __errno_location

        movl %ecx,(%eax)

#else

        movl %eax,errno

#endif /* __UCLIBC_HAS_THREADS__ */

#endif /* __PIC__ */

        movl $-1,%eax

        .p2align 4,,7

.Ldone:

        popl %ebx

        popl %esi

        popl %edi

        ret

.Lsize:

        .size    syscall,.Lsize-syscall