| /* Machine-dependent ELF dynamic relocation inline functions. AM33 version. |
| Copyright (C) 1995-2014 Free Software Foundation, Inc. |
| This file is part of the GNU C Library. |
| |
| The GNU C Library is free software; you can redistribute it and/or |
| modify it under the terms of the GNU Library General Public License as |
| published by the Free Software Foundation; either version 2 of the |
| License, or (at your option) any later version. |
| |
| The GNU C Library is distributed in the hope that it will be useful, |
| but WITHOUT ANY WARRANTY; without even the implied warranty of |
| MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| Library General Public License for more details. |
| |
| You should have received a copy of the GNU Library General Public |
| License along with the GNU C Library. If not, see |
| <http://www.gnu.org/licenses/>. */ |
| |
| #ifndef dl_machine_h |
| #define dl_machine_h |
| |
| #define ELF_MACHINE_NAME "mn10300" |
| |
| #include <sys/param.h> |
| |
| /* Return nonzero iff ELF header is compatible with the running host. */ |
| static inline int __attribute__ ((unused)) |
| elf_machine_matches_host (const Elf32_Ehdr *ehdr) |
| { |
| return ehdr->e_machine == EM_MN10300; |
| } |
| |
| |
| /* Return the link-time address of _DYNAMIC. Conveniently, this is the |
| first element of the GOT. This must be inlined in a function which |
| uses global data. */ |
| static inline Elf32_Addr __attribute__ ((unused)) |
| elf_machine_dynamic (void) |
| { |
| register Elf32_Addr *got asm ("a2"); |
| return *got; |
| } |
| |
| |
| /* Return the run-time load address of the shared object. */ |
| static inline Elf32_Addr __attribute__ ((unused)) |
| elf_machine_load_address (void) |
| { |
| register Elf32_Addr gotaddr asm ("a2"); |
| Elf32_Addr off, gotval; |
| |
| asm ("mov _dl_start@GOTOFF,%0" : "=r" (off)); |
| asm ("mov (_dl_start@GOT,%1),%0" : "=r" (gotval) : "r" (gotaddr)); |
| |
| return off + gotaddr - gotval; |
| } |
| |
| #ifndef PROF |
| /* We add a declaration of this function here so that in dl-runtime.c |
| the ELF_MACHINE_RUNTIME_TRAMPOLINE macro really can pass the parameters |
| in registers. |
| |
| We cannot use this scheme for profiling because the _mcount call |
| destroys the passed register information. */ |
| static ElfW(Addr) fixup (struct link_map *l, ElfW(Word) reloc_offset) |
| __attribute__ ((unused)); |
| static ElfW(Addr) profile_fixup (struct link_map *l, ElfW(Word) reloc_offset, |
| ElfW(Addr) retaddr) |
| __attribute__ ((unused)); |
| #endif |
| |
| /* Set up the loaded object described by L so its unrelocated PLT |
| entries will jump to the on-demand fixup code in dl-runtime.c. */ |
| |
| static inline int __attribute__ ((unused)) |
| elf_machine_runtime_setup (struct link_map *l, int lazy, int profile) |
| { |
| Elf32_Addr *got; |
| extern void _dl_runtime_resolve (Elf32_Word) attribute_hidden; |
| extern void _dl_runtime_profile (Elf32_Word) attribute_hidden; |
| |
| if (l->l_info[DT_JMPREL] && lazy) |
| { |
| /* The GOT entries for functions in the PLT have not yet been filled |
| in. Their initial contents will arrange when called to push an |
| offset into the .rel.plt section, push _GLOBAL_OFFSET_TABLE_[1], |
| and then jump to _GLOBAL_OFFSET_TABLE[2]. */ |
| got = (Elf32_Addr *) D_PTR (l, l_info[DT_PLTGOT]); |
| got[1] = (Elf32_Addr) l; /* Identify this shared object. */ |
| |
| /* The got[2] entry contains the address of a function which gets |
| called to get the address of a so far unresolved function and |
| jump to it. The profiling extension of the dynamic linker allows |
| to intercept the calls to collect information. In this case we |
| don't store the address in the GOT so that all future calls also |
| end in this function. */ |
| if (__builtin_expect (profile, 0)) |
| { |
| got[2] = (Elf32_Addr) &_dl_runtime_profile; |
| |
| if (_dl_name_match_p (GLRO(dl_profile), l)) |
| /* This is the object we are looking for. Say that we really |
| want profiling and the timers are started. */ |
| GL(dl_profile_map) = l; |
| } |
| else |
| /* This function will get called to fix up the GOT entry indicated by |
| the offset on the stack, and then jump to the resolved address. */ |
| got[2] = (Elf32_Addr) &_dl_runtime_resolve; |
| } |
| |
| return lazy; |
| } |
| |
| /* This code is used in dl-runtime.c to call the `fixup' function |
| and then redirect to the address it returns. */ |
| #ifndef PROF |
| # define ELF_MACHINE_RUNTIME_TRAMPOLINE asm ("\ |
| .text\n\ |
| .globl _dl_runtime_resolve\n\ |
| .type _dl_runtime_resolve, @function\n\ |
| _dl_runtime_resolve:\n\ |
| add -12,sp # Preserve registers otherwise clobbered.\n\ |
| mov d1,(20,sp)\n\ |
| mov d0,(16,sp)\n\ |
| mov r1,d0\n\ |
| mov r0,d1\n\ |
| call fixup,[],0 # Call resolver.\n\ |
| mov d0,a0\n\ |
| mov (12,sp),d1 # Copy return address back to mdr,\n\ |
| mov d1,mdr # in case the callee returns with retf\n\ |
| mov (16,sp),d0 # Get register content back.\n\ |
| mov (20,sp),d1\n\ |
| add 12,sp\n\ |
| jmp (a0)\n\ |
| .size _dl_runtime_resolve, .-_dl_runtime_resolve\n\ |
| \n\ |
| .globl _dl_runtime_profile\n\ |
| .type _dl_runtime_profile, @function\n\ |
| _dl_runtime_profile:\n\ |
| add -12,sp # Preserve registers otherwise clobbered.\n\ |
| mov d1,(20,sp)\n\ |
| mov d0,(16,sp)\n\ |
| mov r1,d0\n\ |
| mov r0,d1\n\ |
| call profile_fixup,[],0 # Call resolver.\n\ |
| mov d0,a0\n\ |
| mov (12,sp),d1 # Copy return address back to mdr,\n\ |
| mov d1,mdr # in case the callee returns with retf\n\ |
| mov (16,sp),d0 # Get register content back.\n\ |
| mov (20,sp),d1\n\ |
| add 12,sp\n\ |
| jmp (a0)\n\ |
| .size _dl_runtime_profile, .-_dl_runtime_profile\n\ |
| .previous\n\ |
| "); |
| #else |
| # define ELF_MACHINE_RUNTIME_TRAMPOLINE asm ("\n\ |
| .text\n\ |
| .globl _dl_runtime_resolve\n\ |
| .globl _dl_runtime_profile\n\ |
| .type _dl_runtime_resolve, @function\n\ |
| .type _dl_runtime_profile, @function\n\ |
| _dl_runtime_resolve:\n\ |
| _dl_runtime_profile:\n\ |
| add -12,sp # Preserve registers otherwise clobbered.\n\ |
| mov d1,(20,sp)\n\ |
| mov d0,(16,sp)\n\ |
| mov r1,d0\n\ |
| mov r0,d1\n\ |
| call profile_fixup,[],0 # Call resolver.\n\ |
| mov d0,a0\n\ |
| mov (12,sp),d1 # Copy return address back to mdr,\n\ |
| mov d1,mdr # in case the callee returns with retf\n\ |
| mov (16,sp),d0 # Get register content back.\n\ |
| mov (20,sp),d1\n\ |
| add 12,sp\n\ |
| jmp (a0)\n\ |
| .size _dl_runtime_resolve, .-_dl_runtime_resolve\n\ |
| .size _dl_runtime_profile, .-_dl_runtime_profile\n\ |
| .previous\n\ |
| "); |
| #endif |
| |
| /* Mask identifying addresses reserved for the user program, |
| where the dynamic linker should not map anything. */ |
| #define ELF_MACHINE_USER_ADDRESS_MASK 0xf8000000UL |
| |
| /* Initial entry point code for the dynamic linker. |
| The C function `_dl_start' is the real entry point; |
| its return value is the user program's entry point. */ |
| #define RTLD_START asm ("\n\ |
| .text\n\ |
| .globl _start\n\ |
| .globl _dl_start_user\n\ |
| _start:\n\ |
| mov 0,a3 # Mark the top of the stack\n\ |
| mov sp,a1\n\ |
| add -20,sp # Prepare for function call\n\ |
| mov a1,d0\n\ |
| call _dl_start,[],0\n\ |
| _dl_start_user:\n\ |
| # Save the user entry point address in d2.\n\ |
| mov d0,d2\n\ |
| # Point a2 at the GOT.\n\ |
| 0: mov pc,a2\n\ |
| add _GLOBAL_OFFSET_TABLE_ - (0b-.),a2\n\ |
| # Store the highest stack address\n\ |
| mov (__libc_stack_end@GOT,a2),a0\n\ |
| mov a1,(a0)\n\ |
| # See if we were run as a command with the executable file\n\ |
| # name as an extra leading argument.\n\ |
| mov (_dl_skip_args@GOT,a2),a0\n\ |
| mov (a0),d0\n\ |
| # Pop the original argument count.\n\ |
| mov (20,sp),d3\n\ |
| # Subtract _dl_skip_args from it.\n\ |
| sub d0,d3\n\ |
| # Adjust the stack pointer to skip _dl_skip_args words.\n\ |
| asl2 d0\n\ |
| mov sp,a0\n\ |
| add d0,a0\n\ |
| mov a0,sp\n\ |
| # Push argc back on the stack.\n\ |
| mov d3,(20,sp)\n\ |
| # The special initializer gets called with the stack just\n\ |
| # as the application's entry point will see it; it can\n\ |
| # switch stacks if it moves these contents over.\n\ |
| " RTLD_START_SPECIAL_INIT "\n\ |
| # Load the parameters again.\n\ |
| # (d0, d1, (12,sp), (16,sp)) = (_dl_loaded, argc, argv, envp)\n\ |
| add 24,a0\n\ |
| mov a0,(12,sp) # a0 is 24+sp\n\ |
| mov d3,d1 # d3 contained argc\n\ |
| inc d3\n\ |
| asl2 d3 # d3 is now (argc+1)*4,\n\ |
| add d3,a0 # the offset between argv and envp\n\ |
| mov a0,(16,sp)\n\ |
| mov (_rtld_local@GOTOFF,a2),d0\n\ |
| # Call the function to run the initializers.\n\ |
| call _dl_init@PLT,[],0\n\ |
| # Pass our finalizer function to the user in d0, as per ELF ABI.\n\ |
| mov (_dl_fini@GOT,a2),d0\n\ |
| add 20,sp\n\ |
| # Jump to the user's entry point.\n\ |
| mov d2,a1\n\ |
| jmp (a1)\n\ |
| .previous\n\ |
| "); |
| |
| #ifndef RTLD_START_SPECIAL_INIT |
| #define RTLD_START_SPECIAL_INIT /* nothing */ |
| #endif |
| |
| /* ELF_RTYPE_CLASS_PLT iff TYPE describes relocation of a PLT entry, so |
| PLT entries 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. */ |
| #define elf_machine_type_class(type) \ |
| ((((type) == R_MN10300_JMP_SLOT) * ELF_RTYPE_CLASS_PLT) \ |
| | (((type) == R_MN10300_COPY) * ELF_RTYPE_CLASS_COPY)) |
| |
| /* A reloc type used for ld.so cmdline arg lookups to reject PLT entries. */ |
| #define ELF_MACHINE_JMP_SLOT R_MN10300_JMP_SLOT |
| |
| static inline Elf32_Addr |
| elf_machine_fixup_plt (struct link_map *map, lookup_t t, |
| const Elf32_Rela *reloc, |
| Elf32_Addr *reloc_addr, Elf32_Addr value) |
| { |
| return *reloc_addr = value; |
| } |
| |
| /* Return the final value of a plt relocation. */ |
| static inline Elf32_Addr |
| elf_machine_plt_value (struct link_map *map, const Elf32_Rela *reloc, |
| Elf32_Addr value) |
| { |
| return value + reloc->r_addend; |
| } |
| |
| #endif /* !dl_machine_h */ |
| |
| #ifdef RESOLVE |
| |
| /* The mn10300 never uses Elf32_Rel relocations. */ |
| #define ELF_MACHINE_NO_REL 1 |
| |
| /* Perform the relocation specified by RELOC and SYM (which is fully resolved). |
| MAP is the object containing the reloc. */ |
| |
| static inline void |
| elf_machine_rela (struct link_map *map, const Elf32_Rela *reloc, |
| const Elf32_Sym *sym, const struct r_found_version *version, |
| void *const reloc_addr_arg, int skip_ifunc) |
| { |
| const unsigned int r_type = ELF32_R_TYPE (reloc->r_info); |
| Elf32_Addr value, *reloc_addr; |
| |
| /* Make sure we drop any previous alignment assumptions. */ |
| asm ("" : "=r" (reloc_addr) : "0" (reloc_addr_arg)); |
| |
| #define COPY_UNALIGNED_WORD(sw, tw, align) \ |
| { \ |
| unsigned long *__sl = (void*)&(sw), *__tl = (void*)&(tw); \ |
| unsigned short *__ss = (void*)&(sw), *__ts = (void*)&(tw); \ |
| unsigned char *__sc = (void*)&(sw), *__tc = (void*)&(tw); \ |
| switch ((align)) \ |
| { \ |
| case 0: \ |
| *__tl = *__sl; \ |
| break; \ |
| case 2: \ |
| *__ts++ = *__ss++; \ |
| *__ts = *__ss; \ |
| break; \ |
| default: \ |
| *__tc++ = *__sc++; \ |
| *__tc++ = *__sc++; \ |
| *__tc++ = *__sc++; \ |
| *__tc = *__sc; \ |
| break; \ |
| } \ |
| } |
| |
| #define COPY_UNALIGNED_HALFWORD(sw, tw, align) \ |
| { \ |
| unsigned short *__ss = (void*)&(sw), *__ts = (void*)&(tw); \ |
| unsigned char *__sc = (void*)&(sw), *__tc = (void*)&(tw); \ |
| switch ((align)) \ |
| { \ |
| case 0: \ |
| *__ts = *__ss; \ |
| break; \ |
| default: \ |
| *__tc++ = *__sc++; \ |
| *__tc = *__sc; \ |
| break; \ |
| } \ |
| } |
| |
| #if !defined RTLD_BOOTSTRAP || !defined HAVE_Z_COMBRELOC |
| if (__builtin_expect (r_type == R_MN10300_RELATIVE, 0)) |
| { |
| # if !defined RTLD_BOOTSTRAP && !defined HAVE_Z_COMBRELOC |
| /* 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 (_dl_rtld_map); |
| if (map != &_dl_rtld_map) /* Already done in rtld itself. */ |
| # endif |
| { |
| COPY_UNALIGNED_WORD (*reloc_addr, value, (int) reloc_addr & 3); |
| value += map->l_addr; |
| COPY_UNALIGNED_WORD (value, *reloc_addr, (int) reloc_addr & 3); |
| } |
| } |
| # ifndef RTLD_BOOTSTRAP |
| else if (__builtin_expect (r_type == R_MN10300_NONE, 0)) |
| return; |
| # endif |
| else |
| #endif |
| { |
| #ifndef RTLD_BOOTSTRAP |
| const Elf32_Sym *const refsym = sym; |
| #endif |
| |
| value = RESOLVE (&sym, version, ELF32_R_TYPE (reloc->r_info)); |
| if (sym) |
| value += sym->st_value; |
| value += reloc->r_addend; /* Assume copy relocs have zero addend. */ |
| |
| switch (r_type) |
| { |
| #ifndef RTLD_BOOTSTRAP |
| case R_MN10300_COPY: |
| if (sym == NULL) |
| /* This can happen in trace mode if an object could not be |
| found. */ |
| break; |
| if (sym->st_size > refsym->st_size |
| || (GLRO(dl_verbose) && sym->st_size < refsym->st_size)) |
| { |
| extern char **_dl_argv; |
| const char *strtab; |
| |
| strtab = (const void *) D_PTR (map, l_info[DT_STRTAB]); |
| _dl_error_printf ("\ |
| %s: Symbol `%s' has different size in shared object, consider re-linking\n", |
| _dl_argv[0] ?: "<program name unknown>", |
| strtab + refsym->st_name); |
| } |
| memcpy (reloc_addr, (void *) value, MIN (sym->st_size, |
| refsym->st_size)); |
| break; |
| #endif |
| case R_MN10300_GLOB_DAT: |
| case R_MN10300_JMP_SLOT: |
| /* These addresses are always aligned. */ |
| *reloc_addr = value; |
| break; |
| case R_MN10300_32: |
| COPY_UNALIGNED_WORD (value, *reloc_addr, (int) reloc_addr & 3); |
| break; |
| #ifndef RTLD_BOOTSTRAP |
| case R_MN10300_16: |
| COPY_UNALIGNED_HALFWORD (value, *reloc_addr, (int) reloc_addr & 1); |
| break; |
| case R_MN10300_8: |
| *(char *) reloc_addr = value; |
| break; |
| case R_MN10300_PCREL32: |
| value -= (Elf32_Addr) reloc_addr; |
| COPY_UNALIGNED_WORD (value, *reloc_addr, (int) reloc_addr & 3); |
| break; |
| case R_MN10300_PCREL16: |
| value -= (Elf32_Addr) reloc_addr; |
| COPY_UNALIGNED_HALFWORD (value, *reloc_addr, (int) reloc_addr & 1); |
| break; |
| case R_MN10300_PCREL8: |
| value -= (Elf32_Addr) reloc_addr; |
| *(char *) reloc_addr = (value - (Elf32_Addr) reloc_addr); |
| break; |
| #endif |
| case R_MN10300_NONE: /* Alright, Wilbur. */ |
| break; |
| #if !defined RTLD_BOOTSTRAP || defined _NDEBUG |
| default: |
| _dl_reloc_bad_type (map, ELFW(R_TYPE) (reloc->r_info), 0); |
| break; |
| #endif |
| } |
| |
| } |
| } |
| |
| static inline void |
| elf_machine_rela_relative (Elf32_Addr l_addr, const Elf32_Rela *reloc, |
| void *const reloc_addr_arg) |
| { |
| Elf32_Addr value, *reloc_addr; |
| |
| asm ("" : "=r" (reloc_addr) : "0" (reloc_addr_arg)); |
| |
| COPY_UNALIGNED_WORD (*reloc_addr, value, (int)reloc_addr & 3); |
| value += l_addr; |
| COPY_UNALIGNED_WORD (value, *reloc_addr, (int)reloc_addr & 3); |
| } |
| |
| static inline void |
| elf_machine_lazy_rel (struct link_map *map, |
| Elf32_Addr l_addr, const Elf32_Rela *reloc, |
| int skip_ifunc) |
| { |
| unsigned long int const r_type = ELF32_R_TYPE (reloc->r_info); |
| |
| /* Check for unexpected PLT reloc type. */ |
| if (__builtin_expect (r_type, R_MN10300_JMP_SLOT) == R_MN10300_JMP_SLOT) |
| { |
| Elf32_Addr* const reloc_addr = (void *)(l_addr + reloc->r_offset); |
| Elf32_Addr value; |
| |
| /* Perform a RELATIVE reloc on the .got entry that transfers |
| to the .plt. */ |
| COPY_UNALIGNED_WORD (*reloc_addr, value, (int)reloc_addr & 3); |
| value += l_addr; |
| COPY_UNALIGNED_WORD (value, *reloc_addr, (int)reloc_addr & 3); |
| } |
| else if (__builtin_expect (r_type, R_MN10300_NONE) != R_MN10300_NONE) |
| _dl_reloc_bad_type (map, ELFW(R_TYPE) (reloc->r_info), 1); |
| |
| } |
| |
| #endif /* RESOLVE */ |