diff options
Diffstat (limited to 'gdb/i386-tdep.c')
| -rw-r--r-- | gdb/i386-tdep.c | 282 |
1 files changed, 224 insertions, 58 deletions
diff --git a/gdb/i386-tdep.c b/gdb/i386-tdep.c index 4e3a15f..ddc461e 100644 --- a/gdb/i386-tdep.c +++ b/gdb/i386-tdep.c @@ -1215,52 +1215,195 @@ gdb_print_insn_i386 (bfd_vma memaddr, disassemble_info *info) } +/* This table matches the indices assigned to enum i386_abi. Keep + them in sync. */ +static const char * const i386_abi_names[] = +{ + "<unknown>", + "SVR4", + "NetBSD", + "GNU/Linux", + "GNU/Hurd", + "Solaris", + "FreeBSD", + NULL +}; + + +#define ABI_TAG_OS_GNU_LINUX I386_ABI_LINUX +#define ABI_TAG_OS_GNU_HURD I386_ABI_HURD +#define ABI_TAG_OS_GNU_SOLARIS I386_ABI_INVALID +#define ABI_TAG_OS_FREEBSD I386_ABI_FREEBSD +#define ABI_TAG_OS_NETBSD I386_ABI_NETBSD + static void -process_note_abi_tag_sections (bfd *abfd, asection *sect, void *obj) +process_note_sections (bfd *abfd, asection *sect, void *obj) { - int *os_ident_ptr = obj; + int *abi = obj; const char *name; - unsigned int sect_size; + unsigned int sectsize; name = bfd_get_section_name (abfd, sect); - sect_size = bfd_section_size (abfd, sect); - if (strcmp (name, ".note.ABI-tag") == 0 && sect_size > 0) + sectsize = bfd_section_size (abfd, sect); + + if (strcmp (name, ".note.ABI-tag") == 0 && sectsize > 0) { unsigned int name_length, data_length, note_type; - char *note = alloca (sect_size); + char *note; + + /* If the section is larger than this, it's probably not what we + are looking for. */ + if (sectsize > 128) + sectsize = 128; + + note = alloca (sectsize); bfd_get_section_contents (abfd, sect, note, - (file_ptr) 0, (bfd_size_type) sect_size); + (file_ptr) 0, (bfd_size_type) sectsize); name_length = bfd_h_get_32 (abfd, note); data_length = bfd_h_get_32 (abfd, note + 4); note_type = bfd_h_get_32 (abfd, note + 8); - if (name_length == 4 && data_length == 16 && note_type == 1 - && strcmp (note + 12, "GNU") == 0) - { - int os_number = bfd_h_get_32 (abfd, note + 16); - - /* The case numbers are from abi-tags in glibc. */ - switch (os_number) - { - case 0: - *os_ident_ptr = ELFOSABI_LINUX; - break; - case 1: - *os_ident_ptr = ELFOSABI_HURD; - break; - case 2: - *os_ident_ptr = ELFOSABI_SOLARIS; - break; - default: - internal_error (__FILE__, __LINE__, - "process_note_abi_sections: " - "unknown OS number %d", os_number); - break; - } - } + if (name_length == 4 && data_length == 16 + && note_type == NT_GNU_ABI_TAG + && strcmp (note + 12, "GNU") == 0) + { + int abi_tag_os = bfd_h_get_32 (abfd, note + 16); + + /* The case numbers are from abi-tags in glibc. */ + switch (abi_tag_os) + { + case GNU_ABI_TAG_LINUX: + *abi = ABI_TAG_OS_GNU_LINUX; + break; + + case GNU_ABI_TAG_HURD: + *abi = ABI_TAG_OS_GNU_HURD; + break; + + case GNU_ABI_TAG_SOLARIS: + *abi = ABI_TAG_OS_GNU_SOLARIS; + break; + + default: + internal_error + (__FILE__, __LINE__, + "process_note_abi_sections: unknown ABI OS tag %d", + abi_tag_os); + break; + } + } + else if (name_length == 8 && data_length == 4 + && note_type == NT_FREEBSD_ABI_TAG + && strcmp (note + 12, "FreeBSD") == 0) + *abi = ABI_TAG_OS_FREEBSD; } + /* NetBSD uses a similar trick. */ + else if (strcmp (name, ".note.netbsd.ident") == 0 && sectsize > 0) + { + unsigned int name_length, desc_length, note_type; + char *note; + + /* If the section is larger than this, it's probably not what we are + looking for. */ + if (sectsize > 128) + sectsize = 128; + + note = alloca (sectsize); + + bfd_get_section_contents (abfd, sect, note, + (file_ptr) 0, (bfd_size_type) sectsize); + + name_length = bfd_h_get_32 (abfd, note); + desc_length = bfd_h_get_32 (abfd, note + 4); + note_type = bfd_h_get_32 (abfd, note + 8); + + if (name_length == 7 && desc_length == 4 + && note_type == NT_NETBSD_IDENT + && strcmp (note + 12, "NetBSD") == 0) + *abi = ABI_TAG_OS_NETBSD; + } +} + +static int +i386_elf_abi_from_note (bfd *abfd) +{ + enum i386_abi abi = I386_ABI_UNKNOWN; + + bfd_map_over_sections (abfd, process_note_sections, &abi); + + return abi; +} + +static enum i386_abi +i386_elf_abi (bfd *abfd) +{ + int elfosabi = elf_elfheader (abfd)->e_ident[EI_OSABI]; + + /* The fact that the EI_OSABI byte is set to ELFOSABI_NONE doesn't + necessarily mean that this is a System V ELF binary. To further + distinguish between binaries for differens operating systems, + check for vendor-specific note elements. */ + if (elfosabi == ELFOSABI_NONE) + { + enum i386_abi abi = i386_elf_abi_from_note (abfd); + + if (abi != I386_ABI_UNKNOWN) + return abi; + + /* FreeBSD folks are naughty; they stored the string "FreeBSD" + in the padding of the e_ident field of the ELF header. */ + if (strcmp (&elf_elfheader (abfd)->e_ident[8], "FreeBSD") == 0) + return I386_ABI_FREEBSD; + } + + switch (elfosabi) + { + case ELFOSABI_NONE: + return I386_ABI_SVR4; + case ELFOSABI_FREEBSD: + return I386_ABI_FREEBSD; + } + + return I386_ABI_UNKNOWN; +} + +struct i386_abi_handler +{ + struct i386_abi_handler *next; + enum i386_abi abi; + void (*init_abi)(struct gdbarch_info, struct gdbarch *); +}; + +struct i386_abi_handler *i386_abi_handler_list = NULL; + +void +i386_gdbarch_register_os_abi (enum i386_abi abi, + void (*init_abi)(struct gdbarch_info, + struct gdbarch *)) +{ + struct i386_abi_handler **handler_p; + + for (handler_p = &i386_abi_handler_list; *handler_p != NULL; + handler_p = &(*handler_p)->next) + { + if ((*handler_p)->abi == abi) + { + internal_error + (__FILE__, __LINE__, + "i386_gdbarch_register_abi: A handler for this ABI variant " + "(%d) has already been registered", (int) abi); + /* If user wants to continue, override previous definition. */ + (*handler_p)->init_abi = init_abi; + return; + } + } + (*handler_p) + = (struct i386_abi_handler *) xmalloc (sizeof (struct i386_abi_handler)); + (*handler_p)->next = NULL; + (*handler_p)->abi = abi; + (*handler_p)->init_abi = init_abi; } struct gdbarch * @@ -1268,42 +1411,31 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) { struct gdbarch_tdep *tdep; struct gdbarch *gdbarch; - int os_ident; + enum i386_abi abi = I386_ABI_UNKNOWN; + struct i386_abi_handler *abi_handler; - if (info.abfd != NULL - && bfd_get_flavour (info.abfd) == bfd_target_elf_flavour) + if (info.abfd != NULL) { - os_ident = elf_elfheader (info.abfd)->e_ident[EI_OSABI]; - - /* If os_ident is 0, it is not necessarily the case that we're - on a SYSV system. (ELFOSABI_NONE is defined to be 0.) - GNU/Linux uses a note section to record OS/ABI info, but - leaves e_ident[EI_OSABI] zero. So we have to check for note - sections too. */ - if (os_ident == ELFOSABI_NONE) - bfd_map_over_sections (info.abfd, - process_note_abi_tag_sections, - &os_ident); - - /* If that didn't help us, revert to some non-standard checks. */ - if (os_ident == ELFOSABI_NONE) + switch (bfd_get_flavour (info.abfd)) { - /* FreeBSD folks are naughty; they stored the string - "FreeBSD" in the padding of the e_ident field of the ELF - header. */ - if (strcmp (&elf_elfheader (info.abfd)->e_ident[8], "FreeBSD") == 0) - os_ident = ELFOSABI_FREEBSD; - } + case bfd_target_elf_flavour: + abi= i386_elf_abi (info.abfd); + break; + + default: + /* Not sure what to do here, leave the ABI as unknown. */ + break; + } } - else - os_ident = -1; + /* Find a candidate among extant architectures. */ for (arches = gdbarch_list_lookup_by_info (arches, &info); arches != NULL; arches = gdbarch_list_lookup_by_info (arches->next, &info)) { + /* Make sure the ABI selection matches. */ tdep = gdbarch_tdep (arches->gdbarch); - if (tdep && tdep->os_ident == os_ident) + if (tdep && tdep->abi == abi) return arches->gdbarch; } @@ -1311,7 +1443,7 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) tdep = XMALLOC (struct gdbarch_tdep); gdbarch = gdbarch_alloc (&info, tdep); - tdep->os_ident = os_ident; + tdep->abi = abi; /* FIXME: kettenis/2001-11-24: Although not all IA-32 processors have the SSE registers, it's easier to set the default to 8. */ @@ -1338,6 +1470,40 @@ i386_gdbarch_init (struct gdbarch_info info, struct gdbarch_list *arches) tm-ptx.h, tm-symmetry.h currently override this. Sigh. */ set_gdbarch_num_regs (gdbarch, NUM_GREGS + NUM_FREGS + NUM_SSE_REGS); + /* Hook in ABI-specific overrides, if they have been registered. */ + if (abi == I386_ABI_UNKNOWN) + { + /* Don't complain about not knowing the ABI variant if we don't + have an inferior. */ + if (info.abfd) + fprintf_filtered + (gdb_stderr, "GDB doesn't recognize the ABI of the inferior. " + "Attempting to continue with the default i386 settings"); + } + else + { + for (abi_handler = i386_abi_handler_list; abi_handler != NULL; + abi_handler = abi_handler->next) + if (abi_handler->abi == abi) + break; + + if (abi_handler) + abi_handler->init_abi (info, gdbarch); + else + { + /* We assume that if GDB_MULTI_ARCH is less than + GDB_MULTI_ARCH_TM that an ABI variant can be supported by + overriding definitions in this file. */ + if (GDB_MULTI_ARCH > GDB_MULTI_ARCH_PARTIAL) + fprintf_filtered + (gdb_stderr, + "A handler for the ABI variant \"%s\" is not built into this " + "configuration of GDB. " + "Attempting to continue with the default i386 settings", + i386_abi_names[abi]); + } + } + return gdbarch; } |