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[/] [or1k/] [trunk/] [linux/] [uClibc/] [ldso/] [ldso/] [i386/] [resolve.S] - Rev 1771

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/*
 * This function is _not_ called directly.  It is jumped to (so no return
 * address is on the stack) when attempting to use a symbol that has not yet
 * been resolved.  The first time a jump symbol (such as a function call inside
 * a shared library) is used (before it gets resolved) it will jump here to
 * _dl_linux_resolve.  When we get called the stack looks like this:
 *      reloc_entry
 *      tpnt
 *
 * This function saves all the registers, puts a copy of reloc_entry and tpnt
 * on the stack (as function arguments) then make the function call
 * _dl_linux_resolver(tpnt, reloc_entry).  _dl_linux_resolver() figures out
 * where the jump symbol is _really_ supposed to have jumped to and returns
 * that to us.  Once we have that, we overwrite tpnt with this fixed up
 * address. We then clean up after ourselves, put all the registers back how we
 * found them, then we jump to where the fixed up address, which is where the
 * jump symbol that got us here really wanted to jump to in the first place.
 * found them, then we jump to the fixed up address, which is where the jump
 * symbol that got us here really wanted to jump to in the first place.  
 *  -Erik Andersen
 */

.text
.align 4

.globl _dl_linux_resolve
.type   _dl_linux_resolve,@function

_dl_linux_resolve:
        pusha                           /* preserve all regs */
        lea     0x20(%esp),%eax         /* eax = tpnt and reloc_entry params */
        pushl   4(%eax)                 /* push copy of reloc_entry param */
        pushl   (%eax)                  /* push copy of tpnt param */
                                         
#ifdef __PIC__
        call    .L24
.L24:
        popl    %ebx
        addl    $_GLOBAL_OFFSET_TABLE_+[.-.L24],%ebx
        movl _dl_linux_resolver@GOT(%ebx),%ebx  /* eax = resolved func */
        call *%ebx
#else
        call _dl_linux_resolver
#endif
        movl    %eax,0x28(%esp)         /* store func addr over original
                                         * tpnt param */
        addl    $0x8,%esp               /* remove copy parameters */
        popa                            /* restore regs */
        ret     $4                      /* jump to func removing original
                                         * reloc_entry param from stack */
.LFE2:
        .size _dl_linux_resolve,.LFE2-_dl_linux_resolve

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