dl-startup.h

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/*
 * Architecture specific code used by dl-startup.c
 */

/* This code fixes the stack pointer so that the dynamic linker
 * can find argc, argv and auxvt (Auxillary Vector Table).  */
asm(""					\
"	.text\n"			\
"	.globl _dl_boot\n"		\
"	.type _dl_boot,@function\n"	\
"_dl_boot:\n"				\
"	move.d $sp,$r10\n"		\
"	move.d $pc,$r9\n"		\
"	add.d _dl_boot2 - ., $r9\n"	\
"	jsr $r9\n"			\
);

#define DL_BOOT(X) static void __attribute_used__ _dl_boot2 (X)


/* Get a pointer to the argv array.  On many platforms this can be just
 * the address if the first argument, on other platforms we need to
 * do something a little more subtle here.  */
#define GET_ARGV(ARGVP, ARGS) ARGVP = ((unsigned long *) ARGS)

/* Handle relocation of the symbols in the dynamic loader. */
static inline
void PERFORM_BOOTSTRAP_RELOC(ELF_RELOC *rpnt, unsigned long *reloc_addr,
	unsigned long symbol_addr, unsigned long load_addr, Elf32_Sym *symtab)
{
	switch (ELF32_R_TYPE(rpnt->r_info)) {
		case R_CRIS_GLOB_DAT:
		case R_CRIS_JUMP_SLOT:
		case R_CRIS_32:
			*reloc_addr = symbol_addr;
			break;
		case R_CRIS_16_PCREL:
			*(short *) *reloc_addr = symbol_addr + rpnt->r_addend - *reloc_addr - 2;
			break;
		case R_CRIS_32_PCREL:
			*reloc_addr = symbol_addr + rpnt->r_addend - *reloc_addr - 4;
			break;
		case R_CRIS_NONE:
			break;
		case R_CRIS_RELATIVE:
			*reloc_addr = load_addr + rpnt->r_addend;
			break;
		default:
			_dl_exit(1);
			break;
	}
}

/* Transfer control to the user's application, once the dynamic loader is
 * done.  This routine has to exit the current function, then call the
 * _dl_elf_main function.  */
#define START() __asm__ volatile ("moveq 0,$r8\n\t" \
				  "move $r8,$srp\n\t" \
				  "move.d %1,$sp\n\t" \
				  "jump %0\n\t" \
				  : : "r" (_dl_elf_main), "r" (args))