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/*
* Various assembly language/system dependent hacks that are required
* so that we can minimize the amount of platform specific code.
* Copyright (C) 2000-2004 by Erik Andersen <andersen@codepoet.org>
*/
#ifndef _ARCH_DL_SYSDEP
#define _ARCH_DL_SYSDEP
/* Define this if the system uses RELOCA. */
#undef ELF_USES_RELOCA
#include <elf.h>
#ifdef __FDPIC__
/* Need bootstrap relocations */
#define ARCH_NEEDS_BOOTSTRAP_RELOCS
#define DL_CHECK_LIB_TYPE(epnt, piclib, _dl_progname, libname) \
do \
{ \
(piclib) = 2; \
} \
while (0)
#endif /* __FDPIC__ */
/* Initialization sequence for the GOT. */
#define INIT_GOT(GOT_BASE,MODULE) \
{ \
GOT_BASE[2] = (unsigned long) _dl_linux_resolve; \
GOT_BASE[1] = (unsigned long) MODULE; \
}
static __always_inline unsigned long arm_modulus(unsigned long m, unsigned long p)
{
unsigned long i,t,inc;
i=p; t=0;
while (!(i&(1<<31))) {
i<<=1;
t++;
}
t--;
for (inc=t;inc>2;inc--) {
i=p<<inc;
if (i&(1<<31))
break;
while (m>=i) {
m-=i;
i<<=1;
if (i&(1<<31))
break;
if (i<p)
break;
}
}
while (m>=p) {
m-=p;
}
return m;
}
#define do_rem(result, n, base) ((result) = arm_modulus(n, base))
#define do_div_10(result, remain) ((result) = (((result) - (remain)) / 2) * -(-1ul / 5ul))
/* Here we define the magic numbers that this dynamic loader should accept */
#define MAGIC1 EM_ARM
#undef MAGIC2
/* Used for error messages */
#define ELF_TARGET "ARM"
struct elf_resolve;
unsigned long _dl_linux_resolver(struct elf_resolve * tpnt, int reloc_entry);
/* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry or
TLS variable, so undefined references should not be allowed to
define the value.
ELF_RTYPE_CLASS_NOCOPY iff TYPE should not be allowed to resolve to one
of the main executable's symbols, as for a COPY reloc. */
#ifdef __FDPIC__
/* Avoid R_ARM_ABS32 to go through the PLT so that R_ARM_TARGET1
translated to R_ARM_ABS32 doesn't use the PLT: otherwise, this
breaks init_array because functions are referenced through the
PLT. */
#define elf_machine_type_class(type) \
((((type) == R_ARM_JUMP_SLOT || (type) == R_ARM_TLS_DTPMOD32 \
|| (type) == R_ARM_FUNCDESC_VALUE || (type) == R_ARM_FUNCDESC || (type) == R_ARM_ABS32 \
|| (type) == R_ARM_TLS_DTPOFF32 || (type) == R_ARM_TLS_TPOFF32) \
* ELF_RTYPE_CLASS_PLT) \
| (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY))
#else
#define elf_machine_type_class(type) \
((((type) == R_ARM_JUMP_SLOT || (type) == R_ARM_TLS_DTPMOD32 \
|| (type) == R_ARM_TLS_DTPOFF32 || (type) == R_ARM_TLS_TPOFF32) \
* ELF_RTYPE_CLASS_PLT) \
| (((type) == R_ARM_COPY) * ELF_RTYPE_CLASS_COPY))
#endif /* __FDPIC__ */
/* Return the link-time address of _DYNAMIC. Conveniently, this is the
first element of the GOT. We used to use the PIC register to do this
without a constant pool reference, but GCC 4.2 will use a pseudo-register
for the PIC base, so it may not be in r10. */
static __always_inline Elf32_Addr __attribute__ ((unused))
elf_machine_dynamic (void)
{
Elf32_Addr dynamic;
#if !defined __thumb__
__asm__ ("ldr %0, 2f\n"
"1: ldr %0, [pc, %0]\n"
"b 3f\n"
"2: .word _GLOBAL_OFFSET_TABLE_ - (1b+8)\n"
"3:" : "=r" (dynamic));
#else
int tmp;
__asm__ (".align 2\n"
"bx pc\n"
"nop\n"
".arm\n"
"ldr %0, 2f\n"
"1: ldr %0, [pc, %0]\n"
"b 3f\n"
"2: .word _GLOBAL_OFFSET_TABLE_ - (1b+8)\n"
"3:"
".align 2\n"
"orr %1, pc, #1\n"
"bx %1\n"
".force_thumb\n"
: "=r" (dynamic), "=&r" (tmp));
#endif
return dynamic;
}
extern char __dl_start[] __asm__("_dl_start");
#ifdef __FDPIC__
/* We must force strings used early in the bootstrap into the data
segment. */
#undef SEND_EARLY_STDERR
#define SEND_EARLY_STDERR(S) \
do { /* FIXME: implement */; } while (0)
#undef INIT_GOT
#include "../fdpic/dl-sysdep.h"
#endif /* __FDPIC__ */
/* Return the run-time load address of the shared object. */
static __always_inline Elf32_Addr __attribute__ ((unused))
elf_machine_load_address (void)
{
#if defined(__FDPIC__)
return 0;
#else
Elf32_Addr got_addr = (Elf32_Addr) &__dl_start;
Elf32_Addr pcrel_addr;
#if defined __OPTIMIZE__ && !defined __thumb__
__asm__ ("adr %0, _dl_start" : "=r" (pcrel_addr));
#else
/* A simple adr does not work in Thumb mode because the offset is
negative, and for debug builds may be too large. */
int tmp;
__asm__ ("adr %1, 1f\n\t"
"ldr %0, [%1]\n\t"
"add %0, %0, %1\n\t"
"b 2f\n\t"
".align 2\n\t"
"1: .word _dl_start - 1b\n\t"
"2:"
: "=r" (pcrel_addr), "=r" (tmp));
#endif
return pcrel_addr - got_addr;
#endif
}
static __always_inline void
#ifdef __FDPIC__
elf_machine_relative (DL_LOADADDR_TYPE load_off, const Elf32_Addr rel_addr,
#else
elf_machine_relative (Elf32_Addr load_off, const Elf32_Addr rel_addr,
#endif
Elf32_Word relative_count)
{
#if defined(__FDPIC__)
Elf32_Rel *rpnt = (void *) rel_addr;
do {
unsigned long *reloc_addr = (unsigned long *) DL_RELOC_ADDR(load_off, rpnt->r_offset);
*reloc_addr = DL_RELOC_ADDR(load_off, *reloc_addr);
rpnt++;
#else
Elf32_Rel * rpnt = (void *) rel_addr;
--rpnt;
do {
Elf32_Addr *const reloc_addr = (void *) (load_off + (++rpnt)->r_offset);
*reloc_addr += load_off;
#endif
} while(--relative_count);
}
#endif /* !_ARCH_DL_SYSDEP */
#ifdef __ARM_EABI__
#define DL_MALLOC_ALIGN 8 /* EABI needs 8 byte alignment for STRD LDRD */
#endif
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