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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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