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778 lines
25 KiB
C
778 lines
25 KiB
C
/* Machine-dependent ELF dynamic relocation inline functions. MIPS version.
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Copyright (C) 1996-2001, 2002, 2003, 2004 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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Contributed by Kazumoto Kojima <kkojima@info.kanagawa-u.ac.jp>.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Lesser General Public
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License as published by the Free Software Foundation; either
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version 2.1 of the License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Lesser General Public License for more details.
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You should have received a copy of the GNU Lesser General Public
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License along with the GNU C Library; if not, write to the Free
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Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
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02111-1307 USA. */
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/* FIXME: Profiling of shared libraries is not implemented yet. */
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#ifndef dl_machine_h
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#define dl_machine_h
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#define ELF_MACHINE_NAME "MIPS"
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#define ELF_MACHINE_NO_PLT
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#include <entry.h>
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#ifndef ENTRY_POINT
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#error ENTRY_POINT needs to be defined for MIPS.
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#endif
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#include <sgidefs.h>
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#include <sys/asm.h>
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/* The offset of gp from GOT might be system-dependent. It's set by
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ld. The same value is also */
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#define OFFSET_GP_GOT 0x7ff0
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#ifndef _RTLD_PROLOGUE
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# define _RTLD_PROLOGUE(entry) \
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".globl\t" __STRING(entry) "\n\t" \
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".ent\t" __STRING(entry) "\n\t" \
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".type\t" __STRING(entry) ", @function\n" \
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__STRING(entry) ":\n\t"
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#endif
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#ifndef _RTLD_EPILOGUE
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# define _RTLD_EPILOGUE(entry) \
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".end\t" __STRING(entry) "\n\t" \
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".size\t" __STRING(entry) ", . - " __STRING(entry) "\n\t"
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#endif
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/* A reloc type used for ld.so cmdline arg lookups to reject PLT entries.
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This makes no sense on MIPS but we have to define this to R_MIPS_REL32
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to avoid the asserts in dl-lookup.c from blowing. */
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#define ELF_MACHINE_JMP_SLOT R_MIPS_REL32
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#define elf_machine_type_class(type) ELF_RTYPE_CLASS_PLT
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/* Translate a processor specific dynamic tag to the index
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in l_info array. */
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#define DT_MIPS(x) (DT_MIPS_##x - DT_LOPROC + DT_NUM)
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/* If there is a DT_MIPS_RLD_MAP entry in the dynamic section, fill it in
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with the run-time address of the r_debug structure */
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#define ELF_MACHINE_DEBUG_SETUP(l,r) \
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do { if ((l)->l_info[DT_MIPS (RLD_MAP)]) \
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*(ElfW(Addr) *)((l)->l_info[DT_MIPS (RLD_MAP)]->d_un.d_ptr) = \
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(ElfW(Addr)) (r); \
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} while (0)
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/* Return nonzero iff ELF header is compatible with the running host. */
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static inline int __attribute_used__
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elf_machine_matches_host (const ElfW(Ehdr) *ehdr)
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{
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#if _MIPS_SIM == _ABIO32 || _MIPS_SIM == _ABIN32
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/* Don't link o32 and n32 together. */
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if (((ehdr->e_flags & EF_MIPS_ABI2) != 0) != (_MIPS_SIM == _ABIN32))
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return 0;
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#endif
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switch (ehdr->e_machine)
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{
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case EM_MIPS:
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case EM_MIPS_RS3_LE:
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return 1;
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default:
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return 0;
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}
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}
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static inline ElfW(Addr) *
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elf_mips_got_from_gpreg (ElfW(Addr) gpreg)
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{
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/* FIXME: the offset of gp from GOT may be system-dependent. */
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return (ElfW(Addr) *) (gpreg - OFFSET_GP_GOT);
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}
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/* Return the link-time address of _DYNAMIC. Conveniently, this is the
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first element of the GOT. This must be inlined in a function which
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uses global data. We assume its $gp points to the primary GOT. */
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static inline ElfW(Addr)
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elf_machine_dynamic (void)
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{
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register ElfW(Addr) gp __asm__ ("$28");
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return *elf_mips_got_from_gpreg (gp);
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}
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#define STRINGXP(X) __STRING(X)
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#define STRINGXV(X) STRINGV_(X)
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#define STRINGV_(...) # __VA_ARGS__
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/* Return the run-time load address of the shared object. */
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static inline ElfW(Addr)
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elf_machine_load_address (void)
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{
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ElfW(Addr) addr;
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asm (" .set noreorder\n"
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" " STRINGXP (PTR_LA) " %0, 0f\n"
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" bltzal $0, 0f\n"
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" nop\n"
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"0: " STRINGXP (PTR_SUBU) " %0, $31, %0\n"
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" .set reorder\n"
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: "=r" (addr)
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: /* No inputs */
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: "$31");
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return addr;
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}
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/* The MSB of got[1] of a gnu object is set to identify gnu objects. */
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#if _MIPS_SIM == _ABI64
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# define ELF_MIPS_GNU_GOT1_MASK 0x8000000000000000L
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#else
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# define ELF_MIPS_GNU_GOT1_MASK 0x80000000L
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#endif
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/* We can't rely on elf_machine_got_rel because _dl_object_relocation_scope
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fiddles with global data. */
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#define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) \
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do { \
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struct link_map *map = &bootstrap_map; \
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ElfW(Sym) *sym; \
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ElfW(Addr) *got; \
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int i, n; \
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\
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got = (ElfW(Addr) *) D_PTR (map, l_info[DT_PLTGOT]); \
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\
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if (__builtin_expect (map->l_addr == 0, 1)) \
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break; \
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\
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/* got[0] is reserved. got[1] is also reserved for the dynamic object \
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generated by gnu ld. Skip these reserved entries from \
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relocation. */ \
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i = (got[1] & ELF_MIPS_GNU_GOT1_MASK)? 2 : 1; \
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n = map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val; \
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\
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/* Add the run-time displacement to all local got entries. */ \
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while (i < n) \
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got[i++] += map->l_addr; \
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\
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/* Handle global got entries. */ \
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got += n; \
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sym = (ElfW(Sym) *) D_PTR(map, l_info[DT_SYMTAB]) \
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+ map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val; \
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i = (map->l_info[DT_MIPS (SYMTABNO)]->d_un.d_val \
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- map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val); \
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\
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while (i--) \
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{ \
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if (sym->st_shndx == SHN_UNDEF || sym->st_shndx == SHN_COMMON) \
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*got = map->l_addr + sym->st_value; \
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else if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC \
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&& *got != sym->st_value) \
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*got += map->l_addr; \
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else if (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION) \
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{ \
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if (sym->st_other == 0) \
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*got += map->l_addr; \
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} \
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else \
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*got = map->l_addr + sym->st_value; \
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\
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got++; \
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sym++; \
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} \
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} while(0)
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/* Get link map for callers object containing STUB_PC. */
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static inline struct link_map *
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elf_machine_runtime_link_map (ElfW(Addr) gpreg, ElfW(Addr) stub_pc)
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{
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extern int _dl_mips_gnu_objects;
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/* got[1] is reserved to keep its link map address for the shared
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object generated by the gnu linker. If all are such objects, we
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can find the link map from current GPREG simply. If not so, get
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the link map for caller's object containing STUB_PC. */
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if (_dl_mips_gnu_objects)
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{
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ElfW(Addr) *got = elf_mips_got_from_gpreg (gpreg);
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ElfW(Word) g1;
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g1 = ((ElfW(Word) *) got)[1];
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if ((g1 & ELF_MIPS_GNU_GOT1_MASK) != 0)
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{
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struct link_map *l =
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(struct link_map *) (g1 & ~ELF_MIPS_GNU_GOT1_MASK);
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ElfW(Addr) base, limit;
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const ElfW(Phdr) *p = l->l_phdr;
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ElfW(Half) this, nent = l->l_phnum;
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/* For the common case of a stub being called from the containing
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object, STUB_PC will point to somewhere within the object that
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is described by the link map fetched via got[1]. Otherwise we
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have to scan all maps. */
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for (this = 0; this < nent; this++)
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{
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if (p[this].p_type == PT_LOAD)
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{
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base = p[this].p_vaddr + l->l_addr;
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limit = base + p[this].p_memsz;
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if (stub_pc >= base && stub_pc < limit)
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return l;
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}
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}
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}
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}
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struct link_map *l;
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Lmid_t nsid;
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for (nsid = 0; nsid < DL_NNS; ++nsid)
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for (l = GL(dl_ns)[nsid]._ns_loaded; l != NULL; l = l->l_next)
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{
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ElfW(Addr) base, limit;
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const ElfW(Phdr) *p = l->l_phdr;
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ElfW(Half) this, nent = l->l_phnum;
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for (this = 0; this < nent; ++this)
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{
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if (p[this].p_type == PT_LOAD)
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{
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base = p[this].p_vaddr + l->l_addr;
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limit = base + p[this].p_memsz;
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if (stub_pc >= base && stub_pc < limit)
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return l;
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}
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}
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}
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_dl_signal_error (0, NULL, NULL, "cannot find runtime link map");
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return NULL;
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}
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#if _MIPS_SIM == _ABIO32
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#define ELF_DL_FRAME_SIZE 40
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#define ELF_DL_SAVE_ARG_REGS "\
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sw $15, 36($29)\n \
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sw $4, 16($29)\n \
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sw $5, 20($29)\n \
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sw $6, 24($29)\n \
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sw $7, 28($29)\n \
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"
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#define ELF_DL_RESTORE_ARG_REGS "\
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lw $31, 36($29)\n \
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lw $4, 16($29)\n \
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lw $5, 20($29)\n \
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lw $6, 24($29)\n \
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lw $7, 28($29)\n \
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"
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#define IFABIO32(X) X
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#else /* _MIPS_SIM == _ABIN32 || _MIPS_SIM == _ABI64 */
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#define ELF_DL_FRAME_SIZE 80
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#define ELF_DL_SAVE_ARG_REGS "\
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sd $15, 72($29)\n \
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sd $4, 8($29)\n \
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sd $5, 16($29)\n \
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sd $6, 24($29)\n \
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sd $7, 32($29)\n \
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sd $8, 40($29)\n \
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sd $9, 48($29)\n \
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sd $10, 56($29)\n \
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sd $11, 64($29)\n \
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"
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#define ELF_DL_RESTORE_ARG_REGS "\
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ld $31, 72($29)\n \
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ld $4, 8($29)\n \
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ld $5, 16($29)\n \
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ld $6, 24($29)\n \
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ld $7, 32($29)\n \
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ld $8, 40($29)\n \
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ld $9, 48($29)\n \
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ld $10, 56($29)\n \
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ld $11, 64($29)\n \
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"
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#define IFABIO32(X)
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#endif
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/* Define mips specific runtime resolver. The function __dl_runtime_resolve
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is called from assembler function _dl_runtime_resolve which converts
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special argument registers t7 ($15) and t8 ($24):
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t7 address to return to the caller of the function
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t8 index for this function symbol in .dynsym
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to usual c arguments.
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Other architectures call fixup from dl-runtime.c in
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_dl_runtime_resolve. MIPS instead calls __dl_runtime_resolve. We
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have to use our own version because of the way the got section is
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treated on MIPS (we've also got ELF_MACHINE_PLT defined). */
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#define ELF_MACHINE_RUNTIME_TRAMPOLINE \
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/* The flag _dl_mips_gnu_objects is set if all dynamic objects are \
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generated by the gnu linker. */ \
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int _dl_mips_gnu_objects = 1; \
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\
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/* This is called from assembly stubs below which the compiler can't see. */ \
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static ElfW(Addr) \
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__dl_runtime_resolve (ElfW(Word), ElfW(Word), ElfW(Addr), ElfW(Addr)) \
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__attribute_used__; \
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\
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static ElfW(Addr) \
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__dl_runtime_resolve (ElfW(Word) sym_index, \
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ElfW(Word) return_address, \
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ElfW(Addr) old_gpreg, \
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ElfW(Addr) stub_pc) \
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{ \
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struct link_map *l = elf_machine_runtime_link_map (old_gpreg, stub_pc); \
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const ElfW(Sym) *const symtab \
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= (const ElfW(Sym) *) D_PTR (l, l_info[DT_SYMTAB]); \
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const char *strtab = (const void *) D_PTR (l, l_info[DT_STRTAB]); \
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ElfW(Addr) *got \
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= (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]); \
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const ElfW(Word) local_gotno \
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= (const ElfW(Word)) l->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val; \
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const ElfW(Word) gotsym \
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= (const ElfW(Word)) l->l_info[DT_MIPS (GOTSYM)]->d_un.d_val; \
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const ElfW(Sym) *sym = &symtab[sym_index]; \
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ElfW(Addr) value; \
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\
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/* FIXME: The symbol versioning stuff is not tested yet. */ \
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if (__builtin_expect (ELFW(ST_VISIBILITY) (sym->st_other), 0) == 0) \
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{ \
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switch (l->l_info[VERSYMIDX (DT_VERSYM)] != NULL) \
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{ \
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default: \
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{ \
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const ElfW(Half) *vernum = \
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(const void *) D_PTR (l, l_info[VERSYMIDX (DT_VERSYM)]); \
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ElfW(Half) ndx = vernum[sym_index] & 0x7fff; \
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const struct r_found_version *version = &l->l_versions[ndx]; \
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\
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if (version->hash != 0) \
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{ \
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value = _dl_lookup_symbol_x (strtab + sym->st_name, l, \
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&sym, l->l_scope, version, \
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ELF_RTYPE_CLASS_PLT, 0, 0); \
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break; \
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} \
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/* Fall through. */ \
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} \
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case 0: \
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value = _dl_lookup_symbol_x (strtab + sym->st_name, l, &sym, \
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l->l_scope, 0, ELF_RTYPE_CLASS_PLT, \
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DL_LOOKUP_ADD_DEPENDENCY, 0); \
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} \
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\
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/* Currently value contains the base load address of the object \
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that defines sym. Now add in the symbol offset. */ \
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value = (sym ? value + sym->st_value : 0); \
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} \
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else \
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/* We already found the symbol. The module (and therefore its load \
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address) is also known. */ \
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value = l->l_addr + sym->st_value; \
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\
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/* Apply the relocation with that value. */ \
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*(got + local_gotno + sym_index - gotsym) = value; \
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\
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return value; \
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} \
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\
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asm ("\n \
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.text\n \
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.align 2\n \
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.globl _dl_runtime_resolve\n \
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.type _dl_runtime_resolve,@function\n \
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.ent _dl_runtime_resolve\n \
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_dl_runtime_resolve:\n \
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.frame $29, " STRINGXP(ELF_DL_FRAME_SIZE) ", $31\n \
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.set noreorder\n \
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# Save GP.\n \
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move $3, $28\n \
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# Save arguments and sp value in stack.\n \
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" STRINGXP(PTR_SUBIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \
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# Modify t9 ($25) so as to point .cpload instruction.\n \
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" IFABIO32(STRINGXP(PTR_ADDIU) " $25, 12\n") " \
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# Compute GP.\n \
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" STRINGXP(SETUP_GP) "\n \
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" STRINGXV(SETUP_GP64 (0, _dl_runtime_resolve)) "\n \
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.set reorder\n \
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# Save slot call pc.\n \
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move $2, $31\n \
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" IFABIO32(STRINGXP(CPRESTORE(32))) "\n \
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" ELF_DL_SAVE_ARG_REGS " \
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move $4, $24\n \
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move $5, $15\n \
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move $6, $3\n \
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move $7, $2\n \
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jal __dl_runtime_resolve\n \
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" ELF_DL_RESTORE_ARG_REGS " \
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" STRINGXP(RESTORE_GP64) "\n \
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" STRINGXP(PTR_ADDIU) " $29, " STRINGXP(ELF_DL_FRAME_SIZE) "\n \
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move $25, $2\n \
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jr $25\n \
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.end _dl_runtime_resolve\n \
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.previous\n \
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");
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/* Mask identifying addresses reserved for the user program,
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where the dynamic linker should not map anything. */
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#define ELF_MACHINE_USER_ADDRESS_MASK 0x80000000UL
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/* Initial entry point code for the dynamic linker.
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The C function `_dl_start' is the real entry point;
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its return value is the user program's entry point.
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Note how we have to be careful about two things:
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1) That we allocate a minimal stack of 24 bytes for
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every function call, the MIPS ABI states that even
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if all arguments are passed in registers the procedure
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called can use the 16 byte area pointed to by $sp
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when it is called to store away the arguments passed
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to it.
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2) That under Linux the entry is named __start
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and not just plain _start. */
|
|
|
|
#define RTLD_START asm (\
|
|
".text\n"\
|
|
_RTLD_PROLOGUE(ENTRY_POINT) "\
|
|
" STRINGXV(SETUP_GPX($25)) "\n\
|
|
" STRINGXV(SETUP_GPX64($18,$25)) "\n\
|
|
# i386 ABI book says that the first entry of GOT holds\n\
|
|
# the address of the dynamic structure. Though MIPS ABI\n\
|
|
# doesn't say nothing about this, I emulate this here.\n\
|
|
" STRINGXP(PTR_LA) " $4, _DYNAMIC\n\
|
|
# Subtract OFFSET_GP_GOT\n\
|
|
" STRINGXP(PTR_S) " $4, -0x7ff0($28)\n\
|
|
move $4, $29\n\
|
|
" STRINGXP(PTR_SUBIU) " $29, 16\n\
|
|
\n\
|
|
" STRINGXP(PTR_LA) " $8, .Lcoff\n\
|
|
bltzal $8, .Lcoff\n\
|
|
.Lcoff: " STRINGXP(PTR_SUBU) " $8, $31, $8\n\
|
|
\n\
|
|
" STRINGXP(PTR_LA) " $25, _dl_start\n\
|
|
" STRINGXP(PTR_ADDU) " $25, $8\n\
|
|
jalr $25\n\
|
|
\n\
|
|
" STRINGXP(PTR_ADDIU) " $29, 16\n\
|
|
# Get the value of label '_dl_start_user' in t9 ($25).\n\
|
|
" STRINGXP(PTR_LA) " $25, _dl_start_user\n\
|
|
.globl _dl_start_user\n\
|
|
.type _dl_start_user,@function\n\
|
|
.aent _dl_start_user\n\
|
|
_dl_start_user:\n\
|
|
" STRINGXP(SETUP_GP) "\n\
|
|
" STRINGXV(SETUP_GP64($18,_dl_start_user)) "\n\
|
|
move $16, $28\n\
|
|
# Save the user entry point address in a saved register.\n\
|
|
move $17, $2\n\
|
|
# See if we were run as a command with the executable file\n\
|
|
# name as an extra leading argument.\n\
|
|
lw $2, _dl_skip_args\n\
|
|
beq $2, $0, 1f\n\
|
|
# Load the original argument count.\n\
|
|
" STRINGXP(PTR_L) " $4, 0($29)\n\
|
|
# Subtract _dl_skip_args from it.\n\
|
|
subu $4, $2\n\
|
|
# Adjust the stack pointer to skip _dl_skip_args words.\n\
|
|
sll $2, " STRINGXP (PTRLOG) "\n\
|
|
" STRINGXP(PTR_ADDU) " $29, $2\n\
|
|
# Save back the modified argument count.\n\
|
|
" STRINGXP(PTR_S) " $4, 0($29)\n\
|
|
1: # Call _dl_init (struct link_map *main_map, int argc, char **argv, char **env) \n\
|
|
" STRINGXP(PTR_L) " $4, _rtld_local\n\
|
|
" STRINGXP(PTR_L) /* or lw??? fixme */ " $5, 0($29)\n\
|
|
" STRINGXP(PTR_LA) " $6, " STRINGXP (PTRSIZE) "($29)\n\
|
|
sll $7, $5, " STRINGXP (PTRLOG) "\n\
|
|
" STRINGXP(PTR_ADDU) " $7, $7, $6\n\
|
|
" STRINGXP(PTR_ADDU) " $7, $7, " STRINGXP (PTRSIZE) " \n\
|
|
" STRINGXP(PTR_SUBIU) " $29, 32\n\
|
|
" STRINGXP(SAVE_GP(16)) "\n\
|
|
# Call the function to run the initializers.\n\
|
|
jal _dl_init_internal\n\
|
|
" STRINGXP(PTR_ADDIU) " $29, 32\n\
|
|
# Pass our finalizer function to the user in $2 as per ELF ABI.\n\
|
|
" STRINGXP(PTR_LA) " $2, _dl_fini\n\
|
|
# Jump to the user entry point.\n\
|
|
move $25, $17\n\
|
|
jr $25\n\t"\
|
|
_RTLD_EPILOGUE(ENTRY_POINT)\
|
|
".previous"\
|
|
);
|
|
|
|
/* The MIPS never uses Elfxx_Rela relocations. */
|
|
#define ELF_MACHINE_NO_RELA 1
|
|
|
|
#endif /* !dl_machine_h */
|
|
|
|
#ifdef RESOLVE
|
|
|
|
/* Perform the relocation specified by RELOC and SYM (which is fully resolved).
|
|
MAP is the object containing the reloc. */
|
|
|
|
static inline void
|
|
#ifdef RTLD_BOOTSTRAP
|
|
__attribute__ ((always_inline))
|
|
#endif
|
|
elf_machine_rel (struct link_map *map, const ElfW(Rel) *reloc,
|
|
const ElfW(Sym) *sym, const struct r_found_version *version,
|
|
void *const reloc_addr)
|
|
{
|
|
const unsigned long int r_type = ELFW(R_TYPE) (reloc->r_info);
|
|
|
|
#if !defined RTLD_BOOTSTRAP && !defined SHARED
|
|
/* This is defined in rtld.c, but nowhere in the static libc.a;
|
|
make the reference weak so static programs can still link. This
|
|
declaration cannot be done when compiling rtld.c (i.e. #ifdef
|
|
RTLD_BOOTSTRAP) because rtld.c contains the common defn for
|
|
_dl_rtld_map, which is incompatible with a weak decl in the same
|
|
file. */
|
|
weak_extern (GL(dl_rtld_map));
|
|
#endif
|
|
|
|
switch (r_type)
|
|
{
|
|
#if _MIPS_SIM == _ABI64
|
|
case (R_MIPS_64 << 8) | R_MIPS_REL32:
|
|
#else
|
|
case R_MIPS_REL32:
|
|
#endif
|
|
{
|
|
int symidx = ELFW(R_SYM) (reloc->r_info);
|
|
ElfW(Addr) reloc_value;
|
|
|
|
/* Support relocations on mis-aligned offsets. Should we ever
|
|
implement RELA, this should be replaced with an assignment
|
|
from reloc->r_addend. */
|
|
__builtin_memcpy (&reloc_value, reloc_addr, sizeof (reloc_value));
|
|
|
|
if (symidx)
|
|
{
|
|
const ElfW(Word) gotsym
|
|
= (const ElfW(Word)) map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val;
|
|
|
|
if ((ElfW(Word))symidx < gotsym)
|
|
{
|
|
/* This wouldn't work for a symbol imported from other
|
|
libraries for which there's no GOT entry, but MIPS
|
|
requires every symbol referenced in a dynamic
|
|
relocation to have a GOT entry in the primary GOT,
|
|
so we only get here for locally-defined symbols.
|
|
For section symbols, we should *NOT* be adding
|
|
sym->st_value (per the definition of the meaning of
|
|
S in reloc expressions in the ELF64 MIPS ABI),
|
|
since it should have already been added to
|
|
reloc_value by the linker, but older versions of
|
|
GNU ld didn't add it, and newer versions don't emit
|
|
useless relocations to section symbols any more, so
|
|
it is safe to keep on adding sym->st_value, even
|
|
though it's not ABI compliant. Some day we should
|
|
bite the bullet and stop doing this. */
|
|
#ifndef RTLD_BOOTSTRAP
|
|
if (map != &GL(dl_rtld_map))
|
|
#endif
|
|
reloc_value += sym->st_value + map->l_addr;
|
|
}
|
|
else
|
|
{
|
|
#ifndef RTLD_BOOTSTRAP
|
|
const ElfW(Addr) *got
|
|
= (const ElfW(Addr) *) D_PTR (map, l_info[DT_PLTGOT]);
|
|
const ElfW(Word) local_gotno
|
|
= (const ElfW(Word))
|
|
map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val;
|
|
|
|
reloc_value += got[symidx + local_gotno - gotsym];
|
|
#endif
|
|
}
|
|
}
|
|
else
|
|
#ifndef RTLD_BOOTSTRAP
|
|
if (map != &GL(dl_rtld_map))
|
|
#endif
|
|
reloc_value += map->l_addr;
|
|
|
|
__builtin_memcpy (reloc_addr, &reloc_value, sizeof (reloc_value));
|
|
}
|
|
break;
|
|
case R_MIPS_NONE: /* Alright, Wilbur. */
|
|
break;
|
|
#if _MIPS_SIM == _ABI64
|
|
case R_MIPS_64:
|
|
/* For full compliance with the ELF64 ABI, one must precede the
|
|
_REL32/_64 pair of relocations with a _64 relocation, such
|
|
that the in-place addend is read as a 64-bit value. IRIX
|
|
didn't pick up on this requirement, so we treat the
|
|
_REL32/_64 relocation as a 64-bit relocation even if it's by
|
|
itself. For ABI compliance, we ignore such _64 dummy
|
|
relocations. For RELA, this may be simply removed, since
|
|
it's totally unnecessary. */
|
|
if (ELFW(R_SYM) (reloc->r_info) == 0)
|
|
break;
|
|
/* Fall through. */
|
|
#endif
|
|
default:
|
|
_dl_reloc_bad_type (map, r_type, 0);
|
|
break;
|
|
}
|
|
}
|
|
|
|
static inline void
|
|
elf_machine_rel_relative (ElfW(Addr) l_addr, const ElfW(Rel) *reloc,
|
|
void *const reloc_addr)
|
|
{
|
|
/* XXX Nothing to do. There is no relative relocation, right? */
|
|
}
|
|
|
|
static inline void
|
|
elf_machine_lazy_rel (struct link_map *map,
|
|
ElfW(Addr) l_addr, const ElfW(Rel) *reloc)
|
|
{
|
|
/* Do nothing. */
|
|
}
|
|
|
|
#ifndef RTLD_BOOTSTRAP
|
|
/* Relocate GOT. */
|
|
static inline void
|
|
elf_machine_got_rel (struct link_map *map, int lazy)
|
|
{
|
|
ElfW(Addr) *got;
|
|
ElfW(Sym) *sym;
|
|
const ElfW(Half) *vernum;
|
|
int i, n, symidx;
|
|
|
|
#define RESOLVE_GOTSYM(sym,vernum,sym_index) \
|
|
({ \
|
|
const ElfW(Sym) *ref = sym; \
|
|
const struct r_found_version *version \
|
|
= vernum ? &map->l_versions[vernum[sym_index] & 0x7fff] : NULL; \
|
|
ElfW(Addr) value; \
|
|
value = RESOLVE (&ref, version, R_MIPS_REL32); \
|
|
(ref)? value + ref->st_value: 0; \
|
|
})
|
|
|
|
if (map->l_info[VERSYMIDX (DT_VERSYM)] != NULL)
|
|
vernum = (const void *) D_PTR (map, l_info[VERSYMIDX (DT_VERSYM)]);
|
|
else
|
|
vernum = NULL;
|
|
|
|
got = (ElfW(Addr) *) D_PTR (map, l_info[DT_PLTGOT]);
|
|
|
|
n = map->l_info[DT_MIPS (LOCAL_GOTNO)]->d_un.d_val;
|
|
/* The dynamic linker's local got entries have already been relocated. */
|
|
if (map != &GL(dl_rtld_map))
|
|
{
|
|
/* got[0] is reserved. got[1] is also reserved for the dynamic object
|
|
generated by gnu ld. Skip these reserved entries from relocation. */
|
|
i = (got[1] & ELF_MIPS_GNU_GOT1_MASK)? 2 : 1;
|
|
|
|
/* Add the run-time displacement to all local got entries if
|
|
needed. */
|
|
if (__builtin_expect (map->l_addr != 0, 0))
|
|
{
|
|
while (i < n)
|
|
got[i++] += map->l_addr;
|
|
}
|
|
}
|
|
|
|
/* Handle global got entries. */
|
|
got += n;
|
|
/* Keep track of the symbol index. */
|
|
symidx = map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val;
|
|
sym = (ElfW(Sym) *) D_PTR (map, l_info[DT_SYMTAB]) + symidx;
|
|
i = (map->l_info[DT_MIPS (SYMTABNO)]->d_un.d_val
|
|
- map->l_info[DT_MIPS (GOTSYM)]->d_un.d_val);
|
|
|
|
/* This loop doesn't handle Quickstart. */
|
|
while (i--)
|
|
{
|
|
if (sym->st_shndx == SHN_UNDEF)
|
|
{
|
|
if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC
|
|
&& sym->st_value && lazy)
|
|
*got = sym->st_value + map->l_addr;
|
|
else
|
|
*got = RESOLVE_GOTSYM (sym, vernum, symidx);
|
|
}
|
|
else if (sym->st_shndx == SHN_COMMON)
|
|
*got = RESOLVE_GOTSYM (sym, vernum, symidx);
|
|
else if (ELFW(ST_TYPE) (sym->st_info) == STT_FUNC
|
|
&& *got != sym->st_value
|
|
&& lazy)
|
|
*got += map->l_addr;
|
|
else if (ELFW(ST_TYPE) (sym->st_info) == STT_SECTION)
|
|
{
|
|
if (sym->st_other == 0)
|
|
*got += map->l_addr;
|
|
}
|
|
else
|
|
*got = RESOLVE_GOTSYM (sym, vernum, symidx);
|
|
|
|
++got;
|
|
++sym;
|
|
++symidx;
|
|
}
|
|
|
|
#undef RESOLVE_GOTSYM
|
|
}
|
|
#endif
|
|
|
|
/* Set up the loaded object described by L so its stub function
|
|
will jump to the on-demand fixup code __dl_runtime_resolve. */
|
|
|
|
static inline int
|
|
elf_machine_runtime_setup (struct link_map *l, int lazy, int profile)
|
|
{
|
|
# ifndef RTLD_BOOTSTRAP
|
|
ElfW(Addr) *got;
|
|
extern void _dl_runtime_resolve (ElfW(Word));
|
|
extern int _dl_mips_gnu_objects;
|
|
|
|
if (lazy)
|
|
{
|
|
/* The GOT entries for functions have not yet been filled in.
|
|
Their initial contents will arrange when called to put an
|
|
offset into the .dynsym section in t8, the return address
|
|
in t7 and then jump to _GLOBAL_OFFSET_TABLE[0]. */
|
|
got = (ElfW(Addr) *) D_PTR (l, l_info[DT_PLTGOT]);
|
|
|
|
/* This function will get called to fix up the GOT entry indicated by
|
|
the register t8, and then jump to the resolved address. */
|
|
got[0] = (ElfW(Addr)) &_dl_runtime_resolve;
|
|
|
|
/* Store l to _GLOBAL_OFFSET_TABLE[1] for gnu object. The MSB
|
|
of got[1] of a gnu object is set to identify gnu objects.
|
|
Where we can store l for non gnu objects? XXX */
|
|
if ((got[1] & ELF_MIPS_GNU_GOT1_MASK) != 0)
|
|
got[1] = ((ElfW(Addr)) l | ELF_MIPS_GNU_GOT1_MASK);
|
|
else
|
|
_dl_mips_gnu_objects = 0;
|
|
}
|
|
|
|
/* Relocate global offset table. */
|
|
elf_machine_got_rel (l, lazy);
|
|
|
|
# endif
|
|
return lazy;
|
|
}
|
|
|
|
#endif /* RESOLVE */
|