understanding elf_machine_load_address

[Guido Guenther <guido.guenther@GMX.NET>]

Hi,
I'm trying to understand to following snippet from glibc's
sysdeps/mips/dl-machine.h:

elf_machine_load_address (void)
{
  ElfW(Addr) addr;
  asm ("	.set noreorder\n"
       "	la %0, here\n"
       "	bltzal $0, here\n"
       "	nop\n"
       "here:	subu %0, $31, %0\n"
       "	.set reorder\n"
       :	"=r" (addr)
       :	/* No inputs */
       :	"$31");
  return addr;
}

As of my understanding addr is zero since $31-%0 is always
zero(%0 stored (before the subu) the address of 'here', as does $31
after the bltzal). Please beat me with a cluebat.
 -- Guido