diff options
Diffstat (limited to 'sysdeps/powerpc/powerpc32/dl-machine.h')
-rw-r--r-- | sysdeps/powerpc/powerpc32/dl-machine.h | 124 |
1 files changed, 103 insertions, 21 deletions
diff --git a/sysdeps/powerpc/powerpc32/dl-machine.h b/sysdeps/powerpc/powerpc32/dl-machine.h index 545c19b300..496fa71ecc 100644 --- a/sysdeps/powerpc/powerpc32/dl-machine.h +++ b/sysdeps/powerpc/powerpc32/dl-machine.h @@ -25,6 +25,10 @@ #include <assert.h> #include <dl-tls.h> +/* Translate a processor specific dynamic tag to the index + in l_info array. */ +#define DT_PPC(x) (DT_PPC_##x - DT_LOPROC + DT_NUM) + /* Return nonzero iff ELF header is compatible with the running host. */ static inline int elf_machine_matches_host (const Elf32_Ehdr *ehdr) @@ -32,24 +36,38 @@ elf_machine_matches_host (const Elf32_Ehdr *ehdr) return ehdr->e_machine == EM_PPC; } +/* Return the value of the GOT pointer. */ +static inline Elf32_Addr * __attribute__ ((const)) +ppc_got (void) +{ + Elf32_Addr *got; +#ifdef HAVE_ASM_PPC_REL16 + asm ("bcl 20,31,1f\n" + "1: mflr %0\n" + " addis %0,%0,_GLOBAL_OFFSET_TABLE_-1b@ha\n" + " addi %0,%0,_GLOBAL_OFFSET_TABLE_-1b@l\n" + : "=b" (got) : : "lr"); +#else + asm (" bl _GLOBAL_OFFSET_TABLE_-4@local" + : "=l" (got)); +#endif + return got; +} /* Return the link-time address of _DYNAMIC, stored as the first value in the GOT. */ -static inline Elf32_Addr +static inline Elf32_Addr __attribute__ ((const)) elf_machine_dynamic (void) { - Elf32_Addr *got; - asm (" bl _GLOBAL_OFFSET_TABLE_-4@local" - : "=l"(got)); - return *got; + return *ppc_got (); } /* Return the run-time load address of the shared object. */ -static inline Elf32_Addr +static inline Elf32_Addr __attribute__ ((const)) elf_machine_load_address (void) { - unsigned int *got; - unsigned int *branchaddr; + Elf32_Addr *branchaddr; + Elf32_Addr runtime_dynamic; /* This is much harder than you'd expect. Possibly I'm missing something. The 'obvious' way: @@ -80,19 +98,17 @@ elf_machine_load_address (void) the address ourselves. That gives us the following code: */ /* Get address of the 'b _DYNAMIC@local'... */ - asm ("bl 0f ;" + asm ("bcl 20,31,0f;" "b _DYNAMIC@local;" "0:" - : "=l"(branchaddr)); - - /* ... and the address of the GOT. */ - asm (" bl _GLOBAL_OFFSET_TABLE_-4@local" - : "=l"(got)); + : "=l" (branchaddr)); /* So now work out the difference between where the branch actually points, and the offset of that location in memory from the start of the file. */ - return ((Elf32_Addr)branchaddr - *got - + ((int)(*branchaddr << 6 & 0xffffff00) >> 6)); + runtime_dynamic = ((Elf32_Addr) branchaddr + + ((Elf32_Sword) (*branchaddr << 6 & 0xffffff00) >> 6)); + + return runtime_dynamic - elf_machine_dynamic (); } #define ELF_MACHINE_BEFORE_RTLD_RELOC(dynamic_info) /* nothing */ @@ -144,13 +160,69 @@ __elf_preferred_address(struct link_map *loader, size_t maplength, /* The PowerPC never uses REL relocations. */ #define ELF_MACHINE_NO_REL 1 -/* Set up the loaded object described by L so its unrelocated PLT +/* Set up the loaded object described by MAP so its unrelocated PLT entries will jump to the on-demand fixup code in dl-runtime.c. Also install a small trampoline to be used by entries that have been relocated to an address too far away for a single branch. */ extern int __elf_machine_runtime_setup (struct link_map *map, int lazy, int profile); -#define elf_machine_runtime_setup __elf_machine_runtime_setup + +static inline int +elf_machine_runtime_setup (struct link_map *map, + int lazy, int profile) +{ + if (map->l_info[DT_JMPREL] == 0) + return lazy; + + if (map->l_info[DT_PPC(GOT)] == 0) + /* Handle old style PLT. */ + return __elf_machine_runtime_setup (map, lazy, profile); + + /* New style non-exec PLT consisting of an array of addresses. */ + map->l_info[DT_PPC(GOT)]->d_un.d_ptr += map->l_addr; + if (lazy) + { + Elf32_Addr *plt, *got, glink; + Elf32_Word num_plt_entries; + void (*dlrr) (void); + extern void _dl_runtime_resolve (void); + extern void _dl_prof_resolve (void); + + if (__builtin_expect (!profile, 1)) + dlrr = _dl_runtime_resolve; + else + { + if (GLRO(dl_profile) != NULL + &&_dl_name_match_p (GLRO(dl_profile), map)) + GL(dl_profile_map) = map; + dlrr = _dl_prof_resolve; + } + got = (Elf32_Addr *) map->l_info[DT_PPC(GOT)]->d_un.d_ptr; + glink = got[1]; + got[1] = (Elf32_Addr) dlrr; + got[2] = (Elf32_Addr) map; + + /* Relocate everything in .plt by the load address offset. */ + plt = (Elf32_Addr *) D_PTR (map, l_info[DT_PLTGOT]); + num_plt_entries = (map->l_info[DT_PLTRELSZ]->d_un.d_val + / sizeof (Elf32_Rela)); + + /* If a library is prelinked but we have to relocate anyway, + we have to be able to undo the prelinking of .plt section. + The prelinker saved us at got[1] address of .glink + section's start. */ + if (glink) + { + glink += map->l_addr; + while (num_plt_entries-- != 0) + *plt++ = glink, glink += 4; + } + else + while (num_plt_entries-- != 0) + *plt++ += map->l_addr; + } + return lazy; +} /* Change the PLT entry whose reloc is 'reloc' to call the actual routine. */ extern Elf32_Addr __elf_machine_fixup_plt (struct link_map *map, @@ -163,7 +235,12 @@ elf_machine_fixup_plt (struct link_map *map, lookup_t t, const Elf32_Rela *reloc, Elf32_Addr *reloc_addr, Elf64_Addr finaladdr) { - return __elf_machine_fixup_plt (map, reloc, reloc_addr, finaladdr); + if (map->l_info[DT_PPC(GOT)] == 0) + /* Handle old style PLT. */ + return __elf_machine_fixup_plt (map, reloc, reloc_addr, finaladdr); + + *reloc_addr = finaladdr; + return finaladdr; } /* Return the final value of a plt relocation. */ @@ -286,11 +363,16 @@ elf_machine_rela (struct link_map *map, const Elf32_Rela *reloc, break; #endif /* USE_TLS etc. */ -#ifdef RESOLVE_CONFLICT_FIND_MAP case R_PPC_JMP_SLOT: +#ifdef RESOLVE_CONFLICT_FIND_MAP RESOLVE_CONFLICT_FIND_MAP (map, reloc_addr); - /* FALLTHROUGH */ #endif + if (map->l_info[DT_PPC(GOT)] != 0) + { + *reloc_addr = value; + break; + } + /* FALLTHROUGH */ default: __process_machine_rela (map, reloc, sym_map, sym, refsym, |