diff options
author | Daniel Jacobowitz <drow@false.org> | 2008-08-08 19:24:49 +0000 |
---|---|---|
committer | Daniel Jacobowitz <drow@false.org> | 2008-08-08 19:24:49 +0000 |
commit | 861fb55ab50ac986e273334639c4c44bb3353efb (patch) | |
tree | 59222b43abbb363ff95f4d0b6fb94ded6a32f9bf /bfd/elfxx-mips.c | |
parent | 532f93bd8e3c0f2e072037e6cdbad4a8f83ee411 (diff) | |
download | fsf-binutils-gdb-861fb55ab50ac986e273334639c4c44bb3353efb.zip fsf-binutils-gdb-861fb55ab50ac986e273334639c4c44bb3353efb.tar.gz fsf-binutils-gdb-861fb55ab50ac986e273334639c4c44bb3353efb.tar.bz2 |
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
Catherine Moore <clm@codesourcery.com>
Mark Shinwell <shinwell@codesourcery.com>
Maxim Kuvyrkov <maxim@codesourcery.com>
* elf32-mips.c (mips_vxworks_copy_howto_rela): Replace with...
(elf_mips_copy_howto): ...this howto. Clear the size fields.
(mips_vxworks_jump_slot_howto_rela): Replace with...
(elf_mips_jump_slot_howto): ...this howto.
(bfd_elf32_bfd_reloc_type_lookup): Handle BFD_RELOC_MIPS_COPY
and BFD_RELOC_MIPS_JUMP_SLOT.
(bfd_elf32_bfd_reloc_name_lookup): Handle "R_MIPS_COPY" and
"R_MIPS_JUMP_SLOT".
(mips_elf32_rtype_to_howto): Handle R_MIPS_COPY and R_MIPS_JUMP_SLOT.
(elf_backend_plt_readonly): Define.
(elf_backend_plt_sym_val): Define for non-VxWorks targets.
(mips_vxworks_bfd_reloc_type_lookup): Delete.
(mips_vxworks_bfd_reloc_name_lookup): Likewise.
(mips_vxworks_rtype_to_howto): Likewise.
(elf_backend_want_dynbss): Don't define for VxWorks.
(elf_backend_plt_readonly): Likewise.
(bfd_elf32_bfd_reloc_type_lookup): Likewise.
(bfd_elf32_bfd_reloc_name_lookup): Likewise.
(elf_backend_mips_rtype_to_howto): Likewise.
(elf_backend_adjust_dynamic_symbol): Likewise.
(elf_backend_got_symbol_offset): Don't define.
* elfn32-mips.c (elf_mips_copy_howto, elf_mips_jump_slot_howto): New.
(bfd_elf32_bfd_reloc_type_lookup): Handle BFD_RELOC_MIPS_COPY
and BFD_RELOC_MIPS_JUMP_SLOT.
(bfd_elf32_bfd_reloc_name_lookup): Handle "R_MIPS_COPY" and
"R_MIPS_JUMP_SLOT".
(mips_elf32_n32_rtype_to_howto): Handle R_MIPS_COPY and
R_MIPS_JUMP_SLOT.
(elf_backend_rela_plts_and_copies_p, elf_backend_plt_readonly)
(elf_backend_plt_sym_val): Define.
* elf64-mips.c (elf_mips_copy_howto, elf_mips_jump_slot_howto): New.
(bfd_elf64_bfd_reloc_type_lookup): Handle BFD_RELOC_MIPS_COPY
and BFD_RELOC_MIPS_JUMP_SLOT.
(bfd_elf64_bfd_reloc_name_lookup): Handle "R_MIPS_COPY" and
"R_MIPS_JUMP_SLOT".
(mips_elf64_rtype_to_howto): Handle R_MIPS_COPY and R_MIPS_JUMP_SLOT.
(elf_backend_rela_plts_and_copies_p, elf_backend_plt_readonly)
(elf_backend_plt_sym_val): Define.
* elfxx-mips.h (_bfd_mips_vxworks_adjust_dynamic_symbol): Delete.
(_bfd_mips_elf_use_plts_and_copy_relocs, _bfd_mips_elf_init_stubs)
(_bfd_mips_elf_plt_sym_val, _bfd_mips_post_process_headers): Declare.
* elfxx-mips.c (mips_elf_la25_stub): New structure.
(LA25_LUI, LA25_J, LA25_ADDIU): New macros.
(mips_elf_link_hash_entry): Add "la25_stubs", "has_static_relocs"
and "has_nonpic_branches" fields. Remove "is_relocation_target" and
"is_branch_target".
(mips_elf_link_hash_table): Add blank lines. Add
"use_plts_and_copy_relocs", "reserved_gotno", "strampoline",
"la25_stubs" and "add_stub_section" fields.
(mips_htab_traverse_info): New structure.
(PIC_OBJECT_P, MIPS_ELF_LOAD_WORD): New macros.
(MIPS_RESERVED_GOTNO): Delete.
(mips_o32_exec_plt0_entry, mips_n32_exec_plt0_entry)
(mips_n64_exec_plt0_entry, mips_exec_plt_entry): New tables.
(mips_elf_link_hash_newfunc): Update after the changes to
mips_elf_link_hash_entry.
(mips_elf_check_mips16_stubs): Replace the DATA parameter with
an INFO parameter. Don't look through warnings symbols here;
do it in mips_elf_check_symbols instead.
(mips_elf_create_stub_symbol): New function.
(mips_elf_la25_stub_hash, mips_elf_la25_stub_eq): New functions.
(_bfd_mips_elf_init_stubs, mips_elf_local_pic_function_p): Likewise.
(mips_elf_add_la25_intro, mips_elf_add_la25_trampoline): Likewise.
(mips_elf_add_la25_stub, mips_elf_check_symbols): New functions.
(mips_elf_gotplt_index): Check for VxWorks.
(mips_elf_output_dynamic_relocation): Take the relocation index
as an extra parameter. Do not increment reloc_count here.
(mips_elf_initialize_tls_slots): Update the calls to
mips_elf_output_dynamic_relocation accordingly.
(mips_elf_multi_got): Use htab->reserved_gotno instead of
MIPS_RESERVED_GOTNO.
(mips_elf_create_got_section): Don't allocate reserved GOT
entries here. Unconditionally create .got.plt, but don't
set its alignment here.
(mips_elf_relocation_needs_la25_stub): New function.
(mips_elf_calculate_relocation): Redirect branches and jumps to
a non-PIC stub if one exists. Check !h->has_static_relocs instead
of !htab->is_vxworks when deciding whether to create dynamic
relocations for R_MIPS_32, R_MIPS_REL32 and R_MIPS_64.
(_bfd_mips_elf_create_dynamic_sections): Unconditionally call
_bfd_elf_create_dynamic_sections. Unconditionally set up
htab->splt and htab->sdynbss. Set htab->srelplt to ".rel.plt"
if !htab->is_vxworks. Add non-VxWorks values of
htab->plt_header_size and htab->plt_entry_size.
(_bfd_mips_elf_check_relocs): Set pointer_equality_needed for
non-branch static relocations. Set has_nonpic_branches when an la25
stub might be required. Set can_make_dynamic_p to TRUE if R_MIPS_32,
R_MIPS_REL32 and R_MIPS_64 relocations can be made dynamic,
rather than duplicating the condition. Do not make them dynamic
for read-only sections in non-PIC executable objects.
Do not protect this code with dynobj == NULL || htab->sgot == NULL;
handle each group of cases separately. Add a default case that
sets has_static_relocs for non-GOT relocations that cannot be
made dynamic. Don't set is_relocation_target and is_branch_target.
Reject non-PIC static relocations in shared objects.
(_bfd_mips_vxworks_adjust_dynamic_symbol): Fold into...
(_bfd_mips_elf_adjust_dynamic_symbol): ...here, using
htab->use_plts_and_copy_relocs instead of htab->is_vxworks
to select PLT and copy-reloc handling. Set the alignment of
.plt and .got.plt when allocating the first entry. Generalize
code to handle REL as well as RELA sections and 64-bit as well as
32-bit GOT entries. Complain if we find a static-only reloc
against an externally-defined symbol and if we cannot create
dynamic relocations for it. Allocate copy relocs using
mips_elf_allocate_dynamic_relocations on non-VxWorks targets.
Set possibly_dynamic_relocs to 0 when using PLTs or copy relocs.
Skip reserved .got.plt entries.
(_bfd_mips_elf_always_size_sections): Use mips_elf_check_symbols
instead of mips_elf_check_mips16_stubs to process each symbol.
Do the traversal for relocatable objects too.
(mips_elf_lay_out_got): Use htab->reserved_gotno instead of
MIPS_RESERVED_GOTNO.
(_bfd_mips_elf_size_dynamic_sections): Exclude sdynbss if it
is empty. Extend the DT_PLTREL, DT_JMPREL and DT_PLTRELSZ handling
to non-VxWorks targets. Only add DT_REL{,A}, DT_REL{,A}SZ and
DT_REL{,A}ENT if .rel.dyn is nonempty. Create a symbol for the
PLT. Allocate a nop at the end of the PLT. Allocate DT_MIPS_PLTGOT.
(mips_elf_create_la25_stub_info): New function.
(_bfd_mips_elf_finish_dynamic_symbol): Write out PLT entries
and copy relocs where necessary. Check pointer_equality_needed.
(mips_finish_exec_plt): New function.
(_bfd_mips_elf_finish_dynamic_sections): Always set DT_PLTGOT
to the beginning of htab->sgot. Use htab->reserved_gotno instead
of MIPS_RESERVED_GOTNO. Assert htab->use_plts_and_copy_relocs
instead of htab->is_vxworks for DT_PLTREL, DT_PLTRELSZ and DT_JMPREL.
Set DT_PLTREL to DT_REL instead of DT_RELA on non-VxWorks targets.
Use mips_finish_exec_plt to create non-VxWorks PLT headers. Set
DT_MIPS_PLTGOT.
(_bfd_mips_elf_copy_indirect_symbol): Copy has_static_relocs
from the indirect symbol to the direct symbol. Also copy
has_nonpic_branches for indirect symbols.
(_bfd_mips_elf_get_target_dtag): Handle DT_MIPS_PLTGOT and
DT_MIPS_RWPLT.
(_bfd_mips_elf_link_hash_table_create): Initialize the new
mips_elf_link_hash_table fields.
(_bfd_mips_vxworks_link_hash_table_create): Set
use_plts_and_copy_relocs to TRUE. Use TRUE rather than 1
when setting is_vxworks.
(_bfd_mips_elf_use_plts_and_copy_relocs): New function.
(_bfd_mips_elf_final_link): Call mips_elf_create_la25_stub for
each la25_stub.
(_bfd_mips_elf_merge_private_bfd_data): Treat dynamic objects
as PIC. Generalize message about linking PIC and non-PIC.
(_bfd_mips_elf_plt_sym_val, _bfd_mips_post_process_headers): New
functions.
* reloc.c: Update comment near BFD_RELOC_MIPS_JUMP_SLOT.
* bfd-in2.h: Regenerated.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
Catherine Moore <clm@codesourcery.com>
Mark Shinwell <shinwell@codesourcery.com>
* readelf.c (get_mips_symbol_other): Handle STO_MIPS_PLT and
STO_MIPS_PIC.
(slurp_rela_relocs, slurp_rel_relocs): Handle MIPS ELF64 here.
(dump_relocations, debug_apply_relocations): Don't handle it here.
(get_mips_dynamic_type): Handle DT_MIPS_PLTGOT and DT_MIPS_RWPLT.
(print_mips_pltgot_entry): New function.
(process_mips_specific): Dump the PLT GOT.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
* config/tc-mips.c (OPTION_CALL_NONPIC): New macro.
(OPTION_NON_SHARED, OPTION_XGOT, OPTION_MABI, OPTION_32)
(OPTION_N32, OPTION_64, OPTION_MDEBUG, OPTION_NO_MDEBUG)
(OPTION_PDR, OPTION_NO_PDR, OPTION_MVXWORKS_PIC): Bump by 1.
(md_longopts): Add -call_nonpic.
(md_parse_option): Handle OPTION_CALL_NONPIC.
(md_show_usage): Add -call_nonpic.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
* gas/mips/call-nonpic-1.s, gas/mips/call-nonpic-1.d: New test.
* gas/mips/mips.exp: Run it.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
Catherine Moore <clm@codesourcery.com>
Mark Shinwell <shinwell@codesourcery.com>
* mips.h (STO_MIPS_PLT, ELF_ST_IS_MIPS_PLT, ELF_ST_SET_MIPS_PLT)
(STO_MIPS_PIC, DT_MIPS_PLTGOT, DT_MIPS_RWPLT): New macros.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
* emulparams/elf32bmip.sh (GOT): Define, moving .got.plt to...
(OTHER_RELRO_SECTIONS, OTHER_READWRITE_SECTIONS): ...one of these
two variables.
* emulparams/elf32bmipn32-defs.sh: Likewise.
* emultempl/mipself.em: Include ldctor.h, elf/mips.h and elfxx-mips.h.
(is_mips_elf): New macro.
(stub_file, stub_bfd): New variables.
(hook_stub_info): New structure.
(hook_in_stub): New function.
(mips_add_stub_section): Likewise.
(mips_create_output_section_statements): Likewise.
(mips_before_allocation): Likewise.
(real_func): New variable.
(mips_for_each_input_file_wrapper): New function.
(mips_lang_for_each_input_file): Likewise.
(lang_for_each_input_file): Define.
(LDEMUL_BEFORE_ALLOCATION): Likewise.
(LDEMUL_CREATE_OUTPUT_SECTION_STATEMENTS): Likewise.
2008-08-08 Richard Sandiford <rdsandiford@googlemail.com>
Daniel Jacobowitz <dan@codesourcery.com>
* ld-mips-elf/mips16-pic-3a.s,
ld-mips-elf/mips16-pic-3b.s,
ld-mips-elf/mips16-pic-3.dd,
ld-mips-elf/mips16-pic-3.gd,
ld-mips-elf/mips16-pic-3.rd,
ld-mips-elf/mips16-pic-3.inc,
ld-mips-elf/pic-and-nonpic-1a.s,
ld-mips-elf/pic-and-nonpic-1b.s,
ld-mips-elf/pic-and-nonpic-1.ld,
ld-mips-elf/pic-and-nonpic-1.dd,
ld-mips-elf/pic-and-nonpic-1.nd,
ld-mips-elf/pic-and-nonpic-1-rel.dd,
ld-mips-elf/pic-and-nonpic-1-rel.nd,
ld-mips-elf/pic-and-nonpic-2a.s,
ld-mips-elf/pic-and-nonpic-2b.s,
ld-mips-elf/pic-and-nonpic-2.d,
ld-mips-elf/pic-and-nonpic-3a.s,
ld-mips-elf/pic-and-nonpic-3a.ld,
ld-mips-elf/pic-and-nonpic-3a.dd,
ld-mips-elf/pic-and-nonpic-3a.gd,
ld-mips-elf/pic-and-nonpic-3a.sd,
ld-mips-elf/pic-and-nonpic-3b.s,
ld-mips-elf/pic-and-nonpic-3b.ld,
ld-mips-elf/pic-and-nonpic-3b.ad,
ld-mips-elf/pic-and-nonpic-3b.dd,
ld-mips-elf/pic-and-nonpic-3b.gd,
ld-mips-elf/pic-and-nonpic-3b.nd,
ld-mips-elf/pic-and-nonpic-3b.pd,
ld-mips-elf/pic-and-nonpic-3b.rd,
ld-mips-elf/pic-and-nonpic-3b.sd,
ld-mips-elf/pic-and-nonpic-3-error.d,
ld-mips-elf/pic-and-nonpic-4a.s,
ld-mips-elf/pic-and-nonpic-4b.s,
ld-mips-elf/pic-and-nonpic-4b.ld,
ld-mips-elf/pic-and-nonpic-4b.ad,
ld-mips-elf/pic-and-nonpic-4b.dd,
ld-mips-elf/pic-and-nonpic-4b.gd,
ld-mips-elf/pic-and-nonpic-4b.nd,
ld-mips-elf/pic-and-nonpic-4b.rd,
ld-mips-elf/pic-and-nonpic-4b.sd,
ld-mips-elf/pic-and-nonpic-4-error.d,
ld-mips-elf/pic-and-nonpic-5a.s,
ld-mips-elf/pic-and-nonpic-5b.s,
ld-mips-elf/pic-and-nonpic-5b.ld,
ld-mips-elf/pic-and-nonpic-5b.ad,
ld-mips-elf/pic-and-nonpic-5b.dd,
ld-mips-elf/pic-and-nonpic-5b.gd,
ld-mips-elf/pic-and-nonpic-5b.nd,
ld-mips-elf/pic-and-nonpic-5b.rd,
ld-mips-elf/pic-and-nonpic-5b.sd,
ld-mips-elf/pic-and-nonpic-5b.pd,
ld-mips-elf/pic-and-nonpic-6.ld,
ld-mips-elf/pic-and-nonpic-6-o32a.s,
ld-mips-elf/pic-and-nonpic-6-o32b.s,
ld-mips-elf/pic-and-nonpic-6-o32c.s,
ld-mips-elf/pic-and-nonpic-6-o32.ad,
ld-mips-elf/pic-and-nonpic-6-o32.dd,
ld-mips-elf/pic-and-nonpic-6-o32.gd,
ld-mips-elf/pic-and-nonpic-6-o32.nd,
ld-mips-elf/pic-and-nonpic-6-o32.pd,
ld-mips-elf/pic-and-nonpic-6-o32.rd,
ld-mips-elf/pic-and-nonpic-6-o32.sd,
ld-mips-elf/pic-and-nonpic-6-n32a.s,
ld-mips-elf/pic-and-nonpic-6-n32b.s,
ld-mips-elf/pic-and-nonpic-6-n32c.s,
ld-mips-elf/pic-and-nonpic-6-n32.ad,
ld-mips-elf/pic-and-nonpic-6-n32.dd,
ld-mips-elf/pic-and-nonpic-6-n32.gd,
ld-mips-elf/pic-and-nonpic-6-n32.nd,
ld-mips-elf/pic-and-nonpic-6-n32.pd,
ld-mips-elf/pic-and-nonpic-6-n32.rd,
ld-mips-elf/pic-and-nonpic-6-n32.sd,
ld-mips-elf/pic-and-nonpic-6-n64a.s,
ld-mips-elf/pic-and-nonpic-6-n64b.s,
ld-mips-elf/pic-and-nonpic-6-n64c.s,
ld-mips-elf/pic-and-nonpic-6-n64.ad,
ld-mips-elf/pic-and-nonpic-6-n64.dd,
ld-mips-elf/pic-and-nonpic-6-n64.gd,
ld-mips-elf/pic-and-nonpic-6-n64.nd,
ld-mips-elf/pic-and-nonpic-6-n64.pd,
ld-mips-elf/pic-and-nonpic-6-n64.rd,
ld-mips-elf/pic-and-nonpic-6-n64.sd: New tests.
* ld-mips-elf/mips-elf.exp: Run them.
Diffstat (limited to 'bfd/elfxx-mips.c')
-rw-r--r-- | bfd/elfxx-mips.c | 1347 |
1 files changed, 1056 insertions, 291 deletions
diff --git a/bfd/elfxx-mips.c b/bfd/elfxx-mips.c index 5c87ecd..80ce5b2 100644 --- a/bfd/elfxx-mips.c +++ b/bfd/elfxx-mips.c @@ -269,6 +269,41 @@ struct _mips_elf_section_data #define GGA_RELOC_ONLY 1 #define GGA_NONE 2 +/* Information about a non-PIC interface to a PIC function. There are + two ways of creating these interfaces. The first is to add: + + lui $25,%hi(func) + addiu $25,$25,%lo(func) + + immediately before a PIC function "func". The second is to add: + + lui $25,%hi(func) + j func + addiu $25,$25,%lo(func) + + to a separate trampoline section. + + Stubs of the first kind go in a new section immediately before the + target function. Stubs of the second kind go in a single section + pointed to by the hash table's "strampoline" field. */ +struct mips_elf_la25_stub { + /* The generated section that contains this stub. */ + asection *stub_section; + + /* The offset of the stub from the start of STUB_SECTION. */ + bfd_vma offset; + + /* One symbol for the original function. Its location is available + in H->root.root.u.def. */ + struct mips_elf_link_hash_entry *h; +}; + +/* Macros for populating a mips_elf_la25_stub. */ + +#define LA25_LUI(VAL) (0x3c190000 | (VAL)) /* lui t9,VAL */ +#define LA25_J(VAL) (0x08000000 | (((VAL) >> 2) & 0x3ffffff)) /* j VAL */ +#define LA25_ADDIU(VAL) (0x27390000 | (VAL)) /* addiu t9,t9,VAL */ + /* This structure is passed to mips_elf_sort_hash_table_f when sorting the dynamic symbols. */ @@ -299,6 +334,9 @@ struct mips_elf_link_hash_entry /* External symbol information. */ EXTR esym; + /* The la25 stub we have created for ths symbol, if any. */ + struct mips_elf_la25_stub *la25_stub; + /* Number of R_MIPS_32, R_MIPS_REL32, or R_MIPS_64 relocs against this symbol. */ unsigned int possibly_dynamic_relocs; @@ -338,6 +376,11 @@ struct mips_elf_link_hash_entry is against a readonly section. */ unsigned int readonly_reloc : 1; + /* True if there is a relocation against this symbol that must be + resolved by the static linker (in other words, if the relocation + cannot possibly be made dynamic). */ + unsigned int has_static_relocs : 1; + /* True if we must not create a .MIPS.stubs entry for this symbol. This is set, for example, if there are relocations related to taking the function's address, i.e. any but R_MIPS_CALL*16 ones. @@ -348,11 +391,10 @@ struct mips_elf_link_hash_entry in any relocs other than a 16 bit call. */ unsigned int need_fn_stub : 1; - /* Are we referenced by some kind of relocation? */ - unsigned int is_relocation_target : 1; - - /* Are we referenced by branch relocations? */ - unsigned int is_branch_target : 1; + /* True if this symbol is referenced by branch relocations from + any non-PIC input file. This is used to determine whether an + la25 stub is required. */ + unsigned int has_nonpic_branches : 1; /* Does this symbol need a traditional MIPS lazy-binding stub (as opposed to a PLT entry)? */ @@ -369,21 +411,32 @@ struct mips_elf_link_hash_table /* String section indices for the dynamic section symbols. */ bfd_size_type dynsym_sec_strindex[SIZEOF_MIPS_DYNSYM_SECNAMES]; #endif + /* The number of .rtproc entries. */ bfd_size_type procedure_count; + /* The size of the .compact_rel section (if SGI_COMPAT). */ bfd_size_type compact_rel_size; + /* This flag indicates that the value of DT_MIPS_RLD_MAP dynamic entry is set to the address of __rld_obj_head as in IRIX5. */ bfd_boolean use_rld_obj_head; + /* This is the value of the __rld_map or __rld_obj_head symbol. */ bfd_vma rld_value; + /* This is set if we see any mips16 stub sections. */ bfd_boolean mips16_stubs_seen; + + /* True if we can generate copy relocs and PLTs. */ + bfd_boolean use_plts_and_copy_relocs; + /* True if we're generating code for VxWorks. */ bfd_boolean is_vxworks; + /* True if we already reported the small-data section overflow. */ bfd_boolean small_data_overflow_reported; + /* Shortcuts to some dynamic sections, or NULL if they are not being used. */ asection *srelbss; @@ -394,16 +447,51 @@ struct mips_elf_link_hash_table asection *splt; asection *sstubs; asection *sgot; + /* The master GOT information. */ struct mips_got_info *got_info; - /* The size of the PLT header in bytes (VxWorks only). */ + + /* The size of the PLT header in bytes. */ bfd_vma plt_header_size; - /* The size of a PLT entry in bytes (VxWorks only). */ + + /* The size of a PLT entry in bytes. */ bfd_vma plt_entry_size; + /* The number of functions that need a lazy-binding stub. */ bfd_vma lazy_stub_count; + /* The size of a function stub entry in bytes. */ bfd_vma function_stub_size; + + /* The number of reserved entries at the beginning of the GOT. */ + unsigned int reserved_gotno; + + /* The section used for mips_elf_la25_stub trampolines. + See the comment above that structure for details. */ + asection *strampoline; + + /* A table of mips_elf_la25_stubs, indexed by (input_section, offset) + pairs. */ + htab_t la25_stubs; + + /* A function FN (NAME, IS, OS) that creates a new input section + called NAME and links it to output section OS. If IS is nonnull, + the new section should go immediately before it, otherwise it + should go at the (current) beginning of OS. + + The function returns the new section on success, otherwise it + returns null. */ + asection *(*add_stub_section) (const char *, asection *, asection *); +}; + +/* A structure used to communicate with htab_traverse callbacks. */ +struct mips_htab_traverse_info { + /* The usual link-wide information. */ + struct bfd_link_info *info; + bfd *output_bfd; + + /* Starts off FALSE and is set to TRUE if the link should be aborted. */ + bfd_boolean error; }; #define TLS_RELOC_P(r_type) \ @@ -574,6 +662,10 @@ static struct mips_got_info *mips_elf_got_for_ibfd /* This will be used when we sort the dynamic relocation records. */ static bfd *reldyn_sorting_bfd; +/* True if ABFD is a PIC object. */ +#define PIC_OBJECT_P(abfd) \ + ((elf_elfheader (abfd)->e_flags & EF_MIPS_PIC) != 0) + /* Nonzero if ABFD is using the N32 ABI. */ #define ABI_N32_P(abfd) \ ((elf_elfheader (abfd)->e_flags & EF_MIPS_ABI2) != 0) @@ -644,6 +736,10 @@ static bfd *reldyn_sorting_bfd; ? bfd_put_64 (abfd, val, ptr) \ : bfd_put_32 (abfd, val, ptr)) +/* The opcode for word-sized loads (LW or LD). */ +#define MIPS_ELF_LOAD_WORD(abfd) \ + (ABI_64_P (abfd) ? 0xdc000000 : 0x8c000000) + /* Add a dynamic symbol table-entry. */ #define MIPS_ELF_ADD_DYNAMIC_ENTRY(info, tag, val) \ _bfd_elf_add_dynamic_entry (info, tag, val) @@ -677,10 +773,6 @@ static bfd *reldyn_sorting_bfd; #define MINUS_ONE (((bfd_vma)0) - 1) #define MINUS_TWO (((bfd_vma)0) - 2) -/* The number of local .got entries we reserve. */ -#define MIPS_RESERVED_GOTNO(INFO) \ - (mips_elf_hash_table (INFO)->is_vxworks ? 3 : 2) - /* The value to write into got[1] for SVR4 targets, to identify it is a GNU object. The dynamic linker can then use got[1] to store the module pointer. */ @@ -785,6 +877,52 @@ static bfd *reldyn_sorting_bfd; #define CALL_STUB_P(name) CONST_STRNEQ (name, CALL_STUB) #define CALL_FP_STUB_P(name) CONST_STRNEQ (name, CALL_FP_STUB) +/* The format of the first PLT entry in an O32 executable. */ +static const bfd_vma mips_o32_exec_plt0_entry[] = { + 0x3c1c0000, /* lui $28, %hi(&GOTPLT[0]) */ + 0x8f990000, /* lw $25, %lo(&GOTPLT[0])($28) */ + 0x279c0000, /* addiu $28, $28, %lo(&GOTPLT[0]) */ + 0x031cc023, /* subu $24, $24, $28 */ + 0x03e07821, /* move $15, $31 */ + 0x0018c082, /* srl $24, $24, 2 */ + 0x0320f809, /* jalr $25 */ + 0x2718fffe /* subu $24, $24, 2 */ +}; + +/* The format of the first PLT entry in an N32 executable. Different + because gp ($28) is not available; we use t2 ($14) instead. */ +static const bfd_vma mips_n32_exec_plt0_entry[] = { + 0x3c0e0000, /* lui $14, %hi(&GOTPLT[0]) */ + 0x8dd90000, /* lw $25, %lo(&GOTPLT[0])($14) */ + 0x25ce0000, /* addiu $14, $14, %lo(&GOTPLT[0]) */ + 0x030ec023, /* subu $24, $24, $14 */ + 0x03e07821, /* move $15, $31 */ + 0x0018c082, /* srl $24, $24, 2 */ + 0x0320f809, /* jalr $25 */ + 0x2718fffe /* subu $24, $24, 2 */ +}; + +/* The format of the first PLT entry in an N64 executable. Different + from N32 because of the increased size of GOT entries. */ +static const bfd_vma mips_n64_exec_plt0_entry[] = { + 0x3c0e0000, /* lui $14, %hi(&GOTPLT[0]) */ + 0xddd90000, /* ld $25, %lo(&GOTPLT[0])($14) */ + 0x25ce0000, /* addiu $14, $14, %lo(&GOTPLT[0]) */ + 0x030ec023, /* subu $24, $24, $14 */ + 0x03e07821, /* move $15, $31 */ + 0x0018c0c2, /* srl $24, $24, 3 */ + 0x0320f809, /* jalr $25 */ + 0x2718fffe /* subu $24, $24, 2 */ +}; + +/* The format of subsequent PLT entries. */ +static const bfd_vma mips_exec_plt_entry[] = { + 0x3c0f0000, /* lui $15, %hi(.got.plt entry) */ + 0x01f90000, /* l[wd] $25, %lo(.got.plt entry)($15) */ + 0x25f80000, /* addiu $24, $15, %lo(.got.plt entry) */ + 0x03200008 /* jr $25 */ +}; + /* The format of the first PLT entry in a VxWorks executable. */ static const bfd_vma mips_vxworks_exec_plt0_entry[] = { 0x3c190000, /* lui t9, %hi(_GLOBAL_OFFSET_TABLE_) */ @@ -894,6 +1032,7 @@ mips_elf_link_hash_newfunc (struct bfd_hash_entry *entry, /* We use -2 as a marker to indicate that the information has not been set. -1 means there is no associated ifd. */ ret->esym.ifd = -2; + ret->la25_stub = 0; ret->possibly_dynamic_relocs = 0; ret->fn_stub = NULL; ret->call_stub = NULL; @@ -901,10 +1040,10 @@ mips_elf_link_hash_newfunc (struct bfd_hash_entry *entry, ret->tls_type = GOT_NORMAL; ret->global_got_area = GGA_NONE; ret->readonly_reloc = FALSE; + ret->has_static_relocs = FALSE; ret->no_fn_stub = FALSE; ret->need_fn_stub = FALSE; - ret->is_relocation_target = FALSE; - ret->is_branch_target = FALSE; + ret->has_nonpic_branches = FALSE; ret->needs_lazy_stub = FALSE; } @@ -1183,6 +1322,35 @@ mips_elf_create_procedure_table (void *handle, bfd *abfd, return FALSE; } +/* We're going to create a stub for H. Create a symbol for the stub's + value and size, to help make the disassembly easier to read. */ + +static bfd_boolean +mips_elf_create_stub_symbol (struct bfd_link_info *info, + struct mips_elf_link_hash_entry *h, + const char *prefix, asection *s, bfd_vma value, + bfd_vma size) +{ + struct bfd_link_hash_entry *bh; + struct elf_link_hash_entry *elfh; + const char *name; + + /* Create a new symbol. */ + name = ACONCAT ((prefix, h->root.root.root.string, NULL)); + bh = NULL; + if (!_bfd_generic_link_add_one_symbol (info, s->owner, name, + BSF_LOCAL, s, value, NULL, + TRUE, FALSE, &bh)) + return FALSE; + + /* Make it a local function. */ + elfh = (struct elf_link_hash_entry *) bh; + elfh->type = ELF_ST_INFO (STB_LOCAL, STT_FUNC); + elfh->size = size; + elfh->forced_local = 1; + return TRUE; +} + /* We're about to redefine H. Create a symbol to represent H's current value and size, to help make the disassembly easier to read. */ @@ -1262,15 +1430,10 @@ mips16_stub_symndx (asection *sec, const Elf_Internal_Rela *relocs, /* Check the mips16 stubs for a particular symbol, and see if we can discard them. */ -static bfd_boolean -mips_elf_check_mips16_stubs (struct mips_elf_link_hash_entry *h, void *data) +static void +mips_elf_check_mips16_stubs (struct bfd_link_info *info, + struct mips_elf_link_hash_entry *h) { - struct bfd_link_info *info; - - info = (struct bfd_link_info *) data; - if (h->root.root.type == bfd_link_hash_warning) - h = (struct mips_elf_link_hash_entry *) h->root.root.u.i.link; - /* Dynamic symbols must use the standard call interface, in case other objects try to call them. */ if (h->fn_stub != NULL @@ -1315,7 +1478,236 @@ mips_elf_check_mips16_stubs (struct mips_elf_link_hash_entry *h, void *data) h->call_fp_stub->reloc_count = 0; h->call_fp_stub->flags |= SEC_EXCLUDE; } +} + +/* Hashtable callbacks for mips_elf_la25_stubs. */ + +static hashval_t +mips_elf_la25_stub_hash (const void *entry_) +{ + const struct mips_elf_la25_stub *entry; + + entry = (struct mips_elf_la25_stub *) entry_; + return entry->h->root.root.u.def.section->id + + entry->h->root.root.u.def.value; +} + +static int +mips_elf_la25_stub_eq (const void *entry1_, const void *entry2_) +{ + const struct mips_elf_la25_stub *entry1, *entry2; + + entry1 = (struct mips_elf_la25_stub *) entry1_; + entry2 = (struct mips_elf_la25_stub *) entry2_; + return ((entry1->h->root.root.u.def.section + == entry2->h->root.root.u.def.section) + && (entry1->h->root.root.u.def.value + == entry2->h->root.root.u.def.value)); +} + +/* Called by the linker to set up the la25 stub-creation code. FN is + the linker's implementation of add_stub_function. Return true on + success. */ + +bfd_boolean +_bfd_mips_elf_init_stubs (struct bfd_link_info *info, + asection *(*fn) (const char *, asection *, + asection *)) +{ + struct mips_elf_link_hash_table *htab; + + htab = mips_elf_hash_table (info); + htab->add_stub_section = fn; + htab->la25_stubs = htab_try_create (1, mips_elf_la25_stub_hash, + mips_elf_la25_stub_eq, NULL); + if (htab->la25_stubs == NULL) + return FALSE; + + return TRUE; +} + +/* Return true if H is a locally-defined PIC function, in the sense + that it might need $25 to be valid on entry. Note that MIPS16 + functions never need $25 to be valid on entry; they set up $gp + using PC-relative instructions instead. */ + +static bfd_boolean +mips_elf_local_pic_function_p (struct mips_elf_link_hash_entry *h) +{ + return ((h->root.root.type == bfd_link_hash_defined + || h->root.root.type == bfd_link_hash_defweak) + && h->root.def_regular + && !bfd_is_abs_section (h->root.root.u.def.section) + && !ELF_ST_IS_MIPS16 (h->root.other) + && (PIC_OBJECT_P (h->root.root.u.def.section->owner) + || ELF_ST_IS_MIPS_PIC (h->root.other))); +} + +/* STUB describes an la25 stub that we have decided to implement + by inserting an LUI/ADDIU pair before the target function. + Create the section and redirect the function symbol to it. */ + +static bfd_boolean +mips_elf_add_la25_intro (struct mips_elf_la25_stub *stub, + struct bfd_link_info *info) +{ + struct mips_elf_link_hash_table *htab; + char *name; + asection *s, *input_section; + unsigned int align; + + htab = mips_elf_hash_table (info); + + /* Create a unique name for the new section. */ + name = bfd_malloc (11 + sizeof (".text.stub.")); + if (name == NULL) + return FALSE; + sprintf (name, ".text.stub.%d", (int) htab_elements (htab->la25_stubs)); + /* Create the section. */ + input_section = stub->h->root.root.u.def.section; + s = htab->add_stub_section (name, input_section, + input_section->output_section); + if (s == NULL) + return FALSE; + + /* Make sure that any padding goes before the stub. */ + align = input_section->alignment_power; + if (!bfd_set_section_alignment (s->owner, s, align)) + return FALSE; + if (align > 3) + s->size = (1 << align) - 8; + + /* Create a symbol for the stub. */ + mips_elf_create_stub_symbol (info, stub->h, ".pic.", s, s->size, 8); + stub->stub_section = s; + stub->offset = s->size; + + /* Allocate room for it. */ + s->size += 8; + return TRUE; +} + +/* STUB describes an la25 stub that we have decided to implement + with a separate trampoline. Allocate room for it and redirect + the function symbol to it. */ + +static bfd_boolean +mips_elf_add_la25_trampoline (struct mips_elf_la25_stub *stub, + struct bfd_link_info *info) +{ + struct mips_elf_link_hash_table *htab; + asection *s; + + htab = mips_elf_hash_table (info); + + /* Create a trampoline section, if we haven't already. */ + s = htab->strampoline; + if (s == NULL) + { + asection *input_section = stub->h->root.root.u.def.section; + s = htab->add_stub_section (".text", NULL, + input_section->output_section); + if (s == NULL || !bfd_set_section_alignment (s->owner, s, 4)) + return FALSE; + htab->strampoline = s; + } + + /* Create a symbol for the stub. */ + mips_elf_create_stub_symbol (info, stub->h, ".pic.", s, s->size, 16); + stub->stub_section = s; + stub->offset = s->size; + + /* Allocate room for it. */ + s->size += 16; + return TRUE; +} + +/* H describes a symbol that needs an la25 stub. Make sure that an + appropriate stub exists and point H at it. */ + +static bfd_boolean +mips_elf_add_la25_stub (struct bfd_link_info *info, + struct mips_elf_link_hash_entry *h) +{ + struct mips_elf_link_hash_table *htab; + struct mips_elf_la25_stub search, *stub; + bfd_boolean use_trampoline_p; + asection *s; + bfd_vma value; + void **slot; + + /* Prefer to use LUI/ADDIU stubs if the function is at the beginning + of the section and if we would need no more than 2 nops. */ + s = h->root.root.u.def.section; + value = h->root.root.u.def.value; + use_trampoline_p = (value != 0 || s->alignment_power > 4); + + /* Describe the stub we want. */ + search.stub_section = NULL; + search.offset = 0; + search.h = h; + + /* See if we've already created an equivalent stub. */ + htab = mips_elf_hash_table (info); + slot = htab_find_slot (htab->la25_stubs, &search, INSERT); + if (slot == NULL) + return FALSE; + + stub = (struct mips_elf_la25_stub *) *slot; + if (stub != NULL) + { + /* We can reuse the existing stub. */ + h->la25_stub = stub; + return TRUE; + } + + /* Create a permanent copy of ENTRY and add it to the hash table. */ + stub = bfd_malloc (sizeof (search)); + if (stub == NULL) + return FALSE; + *stub = search; + *slot = stub; + + h->la25_stub = stub; + return (use_trampoline_p + ? mips_elf_add_la25_trampoline (stub, info) + : mips_elf_add_la25_intro (stub, info)); +} + +/* A mips_elf_link_hash_traverse callback that is called before sizing + sections. DATA points to a mips_htab_traverse_info structure. */ + +static bfd_boolean +mips_elf_check_symbols (struct mips_elf_link_hash_entry *h, void *data) +{ + struct mips_htab_traverse_info *hti; + + hti = (struct mips_htab_traverse_info *) data; + if (h->root.root.type == bfd_link_hash_warning) + h = (struct mips_elf_link_hash_entry *) h->root.root.u.i.link; + + if (!hti->info->relocatable) + mips_elf_check_mips16_stubs (hti->info, h); + + if (mips_elf_local_pic_function_p (h)) + { + /* H is a function that might need $25 to be valid on entry. + If we're creating a non-PIC relocatable object, mark H as + being PIC. If we're creating a non-relocatable object with + non-PIC branches and jumps to H, make sure that H has an la25 + stub. */ + if (hti->info->relocatable) + { + if (!PIC_OBJECT_P (hti->output_bfd)) + h->root.other = ELF_ST_SET_MIPS_PIC (h->root.other); + } + else if (h->has_nonpic_branches && !mips_elf_add_la25_stub (hti->info, h)) + { + hti->error = TRUE; + return FALSE; + } + } return TRUE; } @@ -2382,6 +2774,7 @@ mips_elf_count_global_tls_relocs (void *arg1, void *arg2) static void mips_elf_output_dynamic_relocation (bfd *output_bfd, asection *sreloc, + unsigned long reloc_index, unsigned long indx, int r_type, bfd_vma offset) @@ -2398,14 +2791,13 @@ mips_elf_output_dynamic_relocation (bfd *output_bfd, (*get_elf_backend_data (output_bfd)->s->swap_reloc_out) (output_bfd, &rel[0], (sreloc->contents - + sreloc->reloc_count * sizeof (Elf64_Mips_External_Rel))); + + reloc_index * sizeof (Elf64_Mips_External_Rel))); } else bfd_elf32_swap_reloc_out (output_bfd, &rel[0], (sreloc->contents - + sreloc->reloc_count * sizeof (Elf32_External_Rel))); - ++sreloc->reloc_count; + + reloc_index * sizeof (Elf32_External_Rel))); } /* Initialize a set of TLS GOT entries for one symbol. */ @@ -2463,13 +2855,13 @@ mips_elf_initialize_tls_slots (bfd *abfd, bfd_vma got_offset, if (need_relocs) { mips_elf_output_dynamic_relocation - (abfd, sreloc, indx, + (abfd, sreloc, sreloc->reloc_count++, indx, ABI_64_P (abfd) ? R_MIPS_TLS_DTPMOD64 : R_MIPS_TLS_DTPMOD32, sgot->output_offset + sgot->output_section->vma + offset); if (indx) mips_elf_output_dynamic_relocation - (abfd, sreloc, indx, + (abfd, sreloc, sreloc->reloc_count++, indx, ABI_64_P (abfd) ? R_MIPS_TLS_DTPREL64 : R_MIPS_TLS_DTPREL32, sgot->output_offset + sgot->output_section->vma + offset2); else @@ -2502,7 +2894,7 @@ mips_elf_initialize_tls_slots (bfd *abfd, bfd_vma got_offset, sgot->contents + offset); mips_elf_output_dynamic_relocation - (abfd, sreloc, indx, + (abfd, sreloc, sreloc->reloc_count++, indx, ABI_64_P (abfd) ? R_MIPS_TLS_TPREL64 : R_MIPS_TLS_TPREL32, sgot->output_offset + sgot->output_section->vma + offset); } @@ -2524,7 +2916,7 @@ mips_elf_initialize_tls_slots (bfd *abfd, bfd_vma got_offset, sgot->contents + got_offset); else mips_elf_output_dynamic_relocation - (abfd, sreloc, indx, + (abfd, sreloc, sreloc->reloc_count++, indx, ABI_64_P (abfd) ? R_MIPS_TLS_DTPMOD64 : R_MIPS_TLS_DTPMOD32, sgot->output_offset + sgot->output_section->vma + got_offset); } @@ -2585,6 +2977,10 @@ mips_elf_gotplt_index (struct bfd_link_info *info, htab = mips_elf_hash_table (info); BFD_ASSERT (h->plt.offset != (bfd_vma) -1); + /* This function only works for VxWorks, because a non-VxWorks .got.plt + section starts with reserved entries. */ + BFD_ASSERT (htab->is_vxworks); + /* Calculate the index of the symbol's PLT entry. */ plt_index = (h->plt.offset - htab->plt_header_size) / htab->plt_entry_size; @@ -3882,7 +4278,7 @@ mips_elf_multi_got (bfd *abfd, struct bfd_link_info *info, got_per_bfd_arg.primary = NULL; got_per_bfd_arg.max_count = ((MIPS_ELF_GOT_MAX_SIZE (info) / MIPS_ELF_GOT_SIZE (abfd)) - - MIPS_RESERVED_GOTNO (info)); + - htab->reserved_gotno); got_per_bfd_arg.max_pages = pages; /* The number of globals that will be included in the primary GOT. See the calls to mips_elf_set_global_got_offset below for more @@ -3993,7 +4389,7 @@ mips_elf_multi_got (bfd *abfd, struct bfd_link_info *info, { struct mips_got_info *gn; - assign += MIPS_RESERVED_GOTNO (info); + assign += htab->reserved_gotno; g->assigned_gotno = assign; g->local_gotno += assign; g->local_gotno += (pages < g->page_gotno ? pages : g->page_gotno); @@ -4050,7 +4446,7 @@ mips_elf_multi_got (bfd *abfd, struct bfd_link_info *info, BFD_ASSERT (g->assigned_gotno == g->next->local_gotno + g->next->global_gotno + g->next->tls_gotno - + MIPS_RESERVED_GOTNO (info)); + + htab->reserved_gotno); } } @@ -4273,9 +4669,9 @@ mips_elf_create_got_section (bfd *abfd, struct bfd_link_info *info) g->global_gotno = 0; g->reloc_only_gotno = 0; g->tls_gotno = 0; - g->local_gotno = MIPS_RESERVED_GOTNO (info); + g->local_gotno = 0; g->page_gotno = 0; - g->assigned_gotno = MIPS_RESERVED_GOTNO (info); + g->assigned_gotno = 0; g->bfd2got = NULL; g->next = NULL; g->tls_ldm_offset = MINUS_ONE; @@ -4291,17 +4687,14 @@ mips_elf_create_got_section (bfd *abfd, struct bfd_link_info *info) mips_elf_section_data (s)->elf.this_hdr.sh_flags |= SHF_ALLOC | SHF_WRITE | SHF_MIPS_GPREL; - /* VxWorks also needs a .got.plt section. */ - if (htab->is_vxworks) - { - s = bfd_make_section_with_flags (abfd, ".got.plt", - SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS - | SEC_IN_MEMORY | SEC_LINKER_CREATED); - if (s == NULL || !bfd_set_section_alignment (abfd, s, 4)) - return FALSE; + /* We also need a .got.plt section when generating PLTs. */ + s = bfd_make_section_with_flags (abfd, ".got.plt", + SEC_ALLOC | SEC_LOAD | SEC_HAS_CONTENTS + | SEC_IN_MEMORY | SEC_LINKER_CREATED); + if (s == NULL) + return FALSE; + htab->sgotplt = s; - htab->sgotplt = s; - } return TRUE; } @@ -4317,6 +4710,34 @@ is_gott_symbol (struct bfd_link_info *info, struct elf_link_hash_entry *h) && (strcmp (h->root.root.string, "__GOTT_BASE__") == 0 || strcmp (h->root.root.string, "__GOTT_INDEX__") == 0)); } + +/* Return TRUE if a relocation of type R_TYPE from INPUT_BFD might + require an la25 stub. See also mips_elf_local_pic_function_p, + which determines whether the destination function ever requires a + stub. */ + +static bfd_boolean +mips_elf_relocation_needs_la25_stub (bfd *input_bfd, int r_type) +{ + /* We specifically ignore branches and jumps from EF_PIC objects, + where the onus is on the compiler or programmer to perform any + necessary initialization of $25. Sometimes such initialization + is unnecessary; for example, -mno-shared functions do not use + the incoming value of $25, and may therefore be called directly. */ + if (PIC_OBJECT_P (input_bfd)) + return FALSE; + + switch (r_type) + { + case R_MIPS_26: + case R_MIPS_PC16: + case R_MIPS16_26: + return TRUE; + + default: + return FALSE; + } +} /* Calculate the value produced by the RELOCATION (which comes from the INPUT_BFD). The ADDEND is the addend to use for this @@ -4617,6 +5038,13 @@ mips_elf_calculate_relocation (bfd *abfd, bfd *input_bfd, BFD_ASSERT (sec->size > 0); symbol = sec->output_section->vma + sec->output_offset; } + /* If this is a direct call to a PIC function, redirect to the + non-PIC stub. */ + else if (h != NULL && h->la25_stub + && mips_elf_relocation_needs_la25_stub (input_bfd, r_type)) + symbol = (h->la25_stub->stub_section->output_section->vma + + h->la25_stub->stub_section->output_offset + + h->la25_stub->offset); /* Calls from 16-bit code to 32-bit code and vice versa require the special jalx instruction. */ @@ -4761,26 +5189,23 @@ mips_elf_calculate_relocation (bfd *abfd, bfd *input_bfd, case R_MIPS_REL32: case R_MIPS_64: if ((info->shared - || (!htab->is_vxworks - && htab->root.dynamic_sections_created + || (htab->root.dynamic_sections_created && h != NULL && h->root.def_dynamic - && !h->root.def_regular)) + && !h->root.def_regular + && !h->has_static_relocs)) && r_symndx != 0 && (h == NULL || h->root.root.type != bfd_link_hash_undefweak || ELF_ST_VISIBILITY (h->root.other) == STV_DEFAULT) && (input_section->flags & SEC_ALLOC) != 0) { - /* If we're creating a shared library, or this relocation is - against a symbol in a shared library, then we can't know + /* If we're creating a shared library, then we can't know where the symbol will end up. So, we create a relocation record in the output, and leave the job up to the dynamic - linker. - - In VxWorks executables, references to external symbols - are handled using copy relocs or PLT stubs, so there's - no need to add a dynamic relocation here. */ + linker. We must do the same for executable references to + shared library symbols, unless we've decided to use copy + relocs or PLTs instead. */ value = addend; if (!mips_elf_create_dynamic_relocation (abfd, info, @@ -6525,24 +6950,29 @@ _bfd_mips_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info) } } + /* Create the .plt, .rel(a).plt, .dynbss and .rel(a).bss sections. + Also create the _PROCEDURE_LINKAGE_TABLE symbol. */ + if (!_bfd_elf_create_dynamic_sections (abfd, info)) + return FALSE; + + /* Cache the sections created above. */ + htab->splt = bfd_get_section_by_name (abfd, ".plt"); + htab->sdynbss = bfd_get_section_by_name (abfd, ".dynbss"); if (htab->is_vxworks) { - /* Create the .plt, .rela.plt, .dynbss and .rela.bss sections. - Also create the _PROCEDURE_LINKAGE_TABLE symbol. */ - if (!_bfd_elf_create_dynamic_sections (abfd, info)) - return FALSE; - - /* Cache the sections created above. */ - htab->sdynbss = bfd_get_section_by_name (abfd, ".dynbss"); htab->srelbss = bfd_get_section_by_name (abfd, ".rela.bss"); htab->srelplt = bfd_get_section_by_name (abfd, ".rela.plt"); - htab->splt = bfd_get_section_by_name (abfd, ".plt"); - if (!htab->sdynbss - || (!htab->srelbss && !info->shared) - || !htab->srelplt - || !htab->splt) - abort (); + } + else + htab->srelplt = bfd_get_section_by_name (abfd, ".rel.plt"); + if (!htab->sdynbss + || (htab->is_vxworks && !htab->srelbss && !info->shared) + || !htab->srelplt + || !htab->splt) + abort (); + if (htab->is_vxworks) + { /* Do the usual VxWorks handling. */ if (!elf_vxworks_create_dynamic_sections (abfd, info, &htab->srelplt2)) return FALSE; @@ -6563,6 +6993,12 @@ _bfd_mips_elf_create_dynamic_sections (bfd *abfd, struct bfd_link_info *info) = 4 * ARRAY_SIZE (mips_vxworks_exec_plt_entry); } } + else if (!info->shared) + { + /* All variants of the plt0 entry are the same size. */ + htab->plt_header_size = 4 * ARRAY_SIZE (mips_o32_exec_plt0_entry); + htab->plt_entry_size = 4 * ARRAY_SIZE (mips_exec_plt_entry); + } return TRUE; } @@ -6979,6 +7415,7 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, unsigned long r_symndx; unsigned int r_type; struct elf_link_hash_entry *h; + bfd_boolean can_make_dynamic_p; r_symndx = ELF_R_SYM (abfd, rel->r_info); r_type = ELF_R_TYPE (abfd, rel->r_info); @@ -6996,69 +7433,89 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, else { h = sym_hashes[r_symndx - extsymoff]; + while (h->root.type == bfd_link_hash_indirect + || h->root.type == bfd_link_hash_warning) + h = (struct elf_link_hash_entry *) h->root.u.i.link; + } - /* This may be an indirect symbol created because of a version. */ - if (h != NULL) + /* Set CAN_MAKE_DYNAMIC_P to true if we can convert this + relocation into a dynamic one. */ + can_make_dynamic_p = FALSE; + switch (r_type) + { + case R_MIPS16_GOT16: + case R_MIPS16_CALL16: + case R_MIPS_GOT16: + case R_MIPS_CALL16: + case R_MIPS_CALL_HI16: + case R_MIPS_CALL_LO16: + case R_MIPS_GOT_HI16: + case R_MIPS_GOT_LO16: + case R_MIPS_GOT_PAGE: + case R_MIPS_GOT_OFST: + case R_MIPS_GOT_DISP: + case R_MIPS_TLS_GOTTPREL: + case R_MIPS_TLS_GD: + case R_MIPS_TLS_LDM: + if (dynobj == NULL) + elf_hash_table (info)->dynobj = dynobj = abfd; + if (!mips_elf_create_got_section (dynobj, info)) + return FALSE; + if (htab->is_vxworks && !info->shared) { - while (h->root.type == bfd_link_hash_indirect) - h = (struct elf_link_hash_entry *) h->root.u.i.link; + (*_bfd_error_handler) + (_("%B: GOT reloc at 0x%lx not expected in executables"), + abfd, (unsigned long) rel->r_offset); + bfd_set_error (bfd_error_bad_value); + return FALSE; } - } + break; - /* Some relocs require a global offset table. */ - if (dynobj == NULL || htab->sgot == NULL) - { - switch (r_type) + case R_MIPS_32: + case R_MIPS_REL32: + case R_MIPS_64: + /* In VxWorks executables, references to external symbols + must be handled using copy relocs or PLT entries; it is not + possible to convert this relocation into a dynamic one. + + For executables that use PLTs and copy-relocs, we have a + choice between converting the relocation into a dynamic + one or using copy relocations or PLT entries. It is + usually better to do the former, unless the relocation is + against a read-only section. */ + if ((info->shared + || (h != NULL + && !htab->is_vxworks + && strcmp (h->root.root.string, "__gnu_local_gp") != 0 + && !(!info->nocopyreloc + && !PIC_OBJECT_P (abfd) + && MIPS_ELF_READONLY_SECTION (sec)))) + && (sec->flags & SEC_ALLOC) != 0) { - case R_MIPS16_GOT16: - case R_MIPS16_CALL16: - case R_MIPS_GOT16: - case R_MIPS_CALL16: - case R_MIPS_CALL_HI16: - case R_MIPS_CALL_LO16: - case R_MIPS_GOT_HI16: - case R_MIPS_GOT_LO16: - case R_MIPS_GOT_PAGE: - case R_MIPS_GOT_OFST: - case R_MIPS_GOT_DISP: - case R_MIPS_TLS_GOTTPREL: - case R_MIPS_TLS_GD: - case R_MIPS_TLS_LDM: + can_make_dynamic_p = TRUE; if (dynobj == NULL) elf_hash_table (info)->dynobj = dynobj = abfd; - if (!mips_elf_create_got_section (dynobj, info)) - return FALSE; - if (htab->is_vxworks && !info->shared) - { - (*_bfd_error_handler) - (_("%B: GOT reloc at 0x%lx not expected in executables"), - abfd, (unsigned long) rel->r_offset); - bfd_set_error (bfd_error_bad_value); - return FALSE; - } break; + } + /* Fall through. */ - case R_MIPS_32: - case R_MIPS_REL32: - case R_MIPS_64: - /* In VxWorks executables, references to external symbols - are handled using copy relocs or PLT stubs, so there's - no need to add a dynamic relocation here. */ - if (dynobj == NULL - && (info->shared || (h != NULL && !htab->is_vxworks)) - && (sec->flags & SEC_ALLOC) != 0) - elf_hash_table (info)->dynobj = dynobj = abfd; - break; + default: + /* Most static relocations require pointer equality, except + for branches. */ + if (h) + h->pointer_equality_needed = TRUE; + /* Fall through. */ - default: - break; - } + case R_MIPS_26: + case R_MIPS_PC16: + case R_MIPS16_26: + if (h) + ((struct mips_elf_link_hash_entry *) h)->has_static_relocs = TRUE; + break; } if (h) { - ((struct mips_elf_link_hash_entry *) h)->is_relocation_target = TRUE; - /* Relocations against the special VxWorks __GOTT_BASE__ and __GOTT_INDEX__ symbols must be left to the loader. Allocate room for them in .rela.dyn. */ @@ -7095,6 +7552,9 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, return FALSE; } + if (h != NULL && mips_elf_relocation_needs_la25_stub (abfd, r_type)) + ((struct mips_elf_link_hash_entry *) h)->has_nonpic_branches = TRUE; + switch (r_type) { case R_MIPS_CALL16: @@ -7136,11 +7596,6 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, struct mips_elf_link_hash_entry *hmips = (struct mips_elf_link_hash_entry *) h; - while (hmips->root.root.type == bfd_link_hash_indirect - || hmips->root.root.type == bfd_link_hash_warning) - hmips = (struct mips_elf_link_hash_entry *) - hmips->root.root.u.i.link; - /* This symbol is definitely not overridable. */ if (hmips->root.def_regular && ! (info->shared && ! info->symbolic @@ -7236,9 +7691,7 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, /* In VxWorks executables, references to external symbols are handled using copy relocs or PLT stubs, so there's no need to add a .rela.dyn entry for this relocation. */ - if ((info->shared || (h != NULL && !htab->is_vxworks)) - && !(h && strcmp (h->root.root.string, "__gnu_local_gp") == 0) - && (sec->flags & SEC_ALLOC) != 0) + if (can_make_dynamic_p) { if (sreloc == NULL) { @@ -7286,16 +7739,7 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, sizeof (Elf32_External_crinfo); break; - case R_MIPS_PC16: - if (h) - ((struct mips_elf_link_hash_entry *) h)->is_branch_target = TRUE; - break; - case R_MIPS_26: - if (h) - ((struct mips_elf_link_hash_entry *) h)->is_branch_target = TRUE; - /* Fall through. */ - case R_MIPS_GPREL16: case R_MIPS_LITERAL: case R_MIPS_GPREL32: @@ -7355,6 +7799,46 @@ _bfd_mips_elf_check_relocs (bfd *abfd, struct bfd_link_info *info, mh = (struct mips_elf_link_hash_entry *) h; mh->need_fn_stub = TRUE; } + + /* Refuse some position-dependent relocations when creating a + shared library. Do not refuse R_MIPS_32 / R_MIPS_64; they're + not PIC, but we can create dynamic relocations and the result + will be fine. Also do not refuse R_MIPS_LO16, which can be + combined with R_MIPS_GOT16. */ + if (info->shared) + { + switch (r_type) + { + case R_MIPS16_HI16: + case R_MIPS_HI16: + case R_MIPS_HIGHER: + case R_MIPS_HIGHEST: + /* Don't refuse a high part relocation if it's against + no symbol (e.g. part of a compound relocation). */ + if (r_symndx == 0) + break; + + /* R_MIPS_HI16 against _gp_disp is used for $gp setup, + and has a special meaning. */ + if (!NEWABI_P (abfd) && h != NULL + && strcmp (h->root.root.string, "_gp_disp") == 0) + break; + + /* FALLTHROUGH */ + + case R_MIPS16_26: + case R_MIPS_26: + howto = MIPS_ELF_RTYPE_TO_HOWTO (abfd, r_type, FALSE); + (*_bfd_error_handler) + (_("%B: relocation %s against `%s' can not be used when making a shared object; recompile with -fPIC"), + abfd, howto->name, + (h) ? h->root.root.string : "a local symbol"); + bfd_set_error (bfd_error_bad_value); + return FALSE; + default: + break; + } + } } return TRUE; @@ -7609,6 +8093,7 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info, htab = mips_elf_hash_table (info); dynobj = elf_hash_table (info)->dynobj; + hmips = (struct mips_elf_link_hash_entry *) h; /* Make sure we know what is going on here. */ BFD_ASSERT (dynobj != NULL @@ -7620,9 +8105,15 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info, hmips = (struct mips_elf_link_hash_entry *) h; - /* For a function, create a stub, if allowed. */ - if (! hmips->no_fn_stub - && h->needs_plt) + /* If there are call relocations against an externally-defined symbol, + see whether we can create a MIPS lazy-binding stub for it. We can + only do this if all references to the function are through call + relocations, and in that case, the traditional lazy-binding stubs + are much more efficient than PLT entries. + + Traditional stubs are only available on SVR4 psABI-based systems; + VxWorks always uses PLTs instead. */ + if (!htab->is_vxworks && h->needs_plt && !hmips->no_fn_stub) { if (! elf_hash_table (info)->dynamic_sections_created) return TRUE; @@ -7638,90 +8129,53 @@ _bfd_mips_elf_adjust_dynamic_symbol (struct bfd_link_info *info, return TRUE; } } - else if ((h->type == STT_FUNC) - && !h->needs_plt) - { - /* This will set the entry for this symbol in the GOT to 0, and - the dynamic linker will take care of this. */ - h->root.u.def.value = 0; - return TRUE; - } + /* As above, VxWorks requires PLT entries for externally-defined + functions that are only accessed through call relocations. - /* If this is a weak symbol, and there is a real definition, the - processor independent code will have arranged for us to see the - real definition first, and we can just use the same value. */ - if (h->u.weakdef != NULL) + Both VxWorks and non-VxWorks targets also need PLT entries if there + are static-only relocations against an externally-defined function. + This can technically occur for shared libraries if there are + branches to the symbol, although it is unlikely that this will be + used in practice due to the short ranges involved. It can occur + for any relative or absolute relocation in executables; in that + case, the PLT entry becomes the function's canonical address. */ + else if (((h->needs_plt && !hmips->no_fn_stub) + || (h->type == STT_FUNC && hmips->has_static_relocs)) + && htab->use_plts_and_copy_relocs + && !SYMBOL_CALLS_LOCAL (info, h) + && !(ELF_ST_VISIBILITY (h->other) != STV_DEFAULT + && h->root.type == bfd_link_hash_undefweak)) { - BFD_ASSERT (h->u.weakdef->root.type == bfd_link_hash_defined - || h->u.weakdef->root.type == bfd_link_hash_defweak); - h->root.u.def.section = h->u.weakdef->root.u.def.section; - h->root.u.def.value = h->u.weakdef->root.u.def.value; - return TRUE; - } - - /* This is a reference to a symbol defined by a dynamic object which - is not a function. */ - - return TRUE; -} - -/* Likewise, for VxWorks. */ + /* If this is the first symbol to need a PLT entry, allocate room + for the header. */ + if (htab->splt->size == 0) + { + BFD_ASSERT (htab->sgotplt->size == 0); -bfd_boolean -_bfd_mips_vxworks_adjust_dynamic_symbol (struct bfd_link_info *info, - struct elf_link_hash_entry *h) -{ - bfd *dynobj; - struct mips_elf_link_hash_entry *hmips; - struct mips_elf_link_hash_table *htab; + /* If we're using the PLT additions to the psABI, each PLT + entry is 16 bytes and the PLT0 entry is 32 bytes. + Encourage better cache usage by aligning. We do this + lazily to avoid pessimizing traditional objects. */ + if (!htab->is_vxworks + && !bfd_set_section_alignment (dynobj, htab->splt, 5)) + return FALSE; - htab = mips_elf_hash_table (info); - dynobj = elf_hash_table (info)->dynobj; - hmips = (struct mips_elf_link_hash_entry *) h; + /* Make sure that .got.plt is word-aligned. We do this lazily + for the same reason as above. */ + if (!bfd_set_section_alignment (dynobj, htab->sgotplt, + MIPS_ELF_LOG_FILE_ALIGN (dynobj))) + return FALSE; - /* Make sure we know what is going on here. */ - BFD_ASSERT (dynobj != NULL - && (h->needs_plt - || h->needs_copy - || h->u.weakdef != NULL - || (h->def_dynamic - && h->ref_regular - && !h->def_regular))); + htab->splt->size += htab->plt_header_size; - /* If the symbol is defined by a dynamic object, we need a PLT stub if - either (a) we want to branch to the symbol or (b) we're linking an - executable that needs a canonical function address. In the latter - case, the canonical address will be the address of the executable's - load stub. */ - if ((hmips->is_branch_target - || (!info->shared - && h->type == STT_FUNC - && hmips->is_relocation_target)) - && h->def_dynamic - && h->ref_regular - && !h->def_regular - && !h->forced_local) - h->needs_plt = 1; - - /* Locally-binding symbols do not need a PLT stub; we can refer to - the functions directly. */ - else if (h->needs_plt - && (SYMBOL_CALLS_LOCAL (info, h) - || (ELF_ST_VISIBILITY (h->other) != STV_DEFAULT - && h->root.type == bfd_link_hash_undefweak))) - { - h->needs_plt = 0; - return TRUE; - } + /* On non-VxWorks targets, the first two entries in .got.plt + are reserved. */ + if (!htab->is_vxworks) + htab->sgotplt->size += 2 * MIPS_ELF_GOT_SIZE (dynobj); - if (h->needs_plt) - { - /* If this is the first symbol to need a PLT entry, allocate room - for the header, and for the header's .rela.plt.unloaded entries. */ - if (htab->splt->size == 0) - { - htab->splt->size += htab->plt_header_size; - if (!info->shared) + /* On VxWorks, also allocate room for the header's + .rela.plt.unloaded entries. */ + if (htab->is_vxworks && !info->shared) htab->srelplt2->size += 2 * sizeof (Elf32_External_Rela); } @@ -7730,35 +8184,33 @@ _bfd_mips_vxworks_adjust_dynamic_symbol (struct bfd_link_info *info, htab->splt->size += htab->plt_entry_size; /* If the output file has no definition of the symbol, set the - symbol's value to the address of the stub. Point at the PLT - load stub rather than the lazy resolution stub; this stub - will become the canonical function address. */ + symbol's value to the address of the stub. */ if (!info->shared && !h->def_regular) { h->root.u.def.section = htab->splt; h->root.u.def.value = h->plt.offset; - h->root.u.def.value += 8; + /* For VxWorks, point at the PLT load stub rather than the + lazy resolution stub; this stub will become the canonical + function address. */ + if (htab->is_vxworks) + h->root.u.def.value += 8; } - /* Make room for the .got.plt entry and the R_JUMP_SLOT relocation. */ - htab->sgotplt->size += 4; - htab->srelplt->size += sizeof (Elf32_External_Rela); + /* Make room for the .got.plt entry and the R_MIPS_JUMP_SLOT + relocation. */ + htab->sgotplt->size += MIPS_ELF_GOT_SIZE (dynobj); + htab->srelplt->size += (htab->is_vxworks + ? MIPS_ELF_RELA_SIZE (dynobj) + : MIPS_ELF_REL_SIZE (dynobj)); /* Make room for the .rela.plt.unloaded relocations. */ - if (!info->shared) + if (htab->is_vxworks && !info->shared) htab->srelplt2->size += 3 * sizeof (Elf32_External_Rela); - return TRUE; - } + /* All relocations against this symbol that could have been made + dynamic will now refer to the PLT entry instead. */ + hmips->possibly_dynamic_relocs = 0; - /* If a function symbol is defined by a dynamic object, and we do not - need a PLT stub for it, the symbol's value should be zero. */ - if (h->type == STT_FUNC - && h->def_dynamic - && h->ref_regular - && !h->def_regular) - { - h->root.u.def.value = 0; return TRUE; } @@ -7774,11 +8226,27 @@ _bfd_mips_vxworks_adjust_dynamic_symbol (struct bfd_link_info *info, return TRUE; } - /* This is a reference to a symbol defined by a dynamic object which - is not a function. */ - if (info->shared) + /* Otherwise, there is nothing further to do for symbols defined + in regular objects. */ + if (h->def_regular) return TRUE; + /* There's also nothing more to do if we'll convert all relocations + against this symbol into dynamic relocations. */ + if (!hmips->has_static_relocs) + return TRUE; + + /* We're now relying on copy relocations. Complain if we have + some that we can't convert. */ + if (!htab->use_plts_and_copy_relocs || info->shared) + { + (*_bfd_error_handler) (_("non-dynamic relocations refer to " + "dynamic symbol %s"), + h->root.root.string); + bfd_set_error (bfd_error_bad_value); + return FALSE; + } + /* We must allocate the symbol in our .dynbss section, which will become part of the .bss section of the executable. There will be an entry for this symbol in the .dynsym section. The dynamic @@ -7791,10 +8259,17 @@ _bfd_mips_vxworks_adjust_dynamic_symbol (struct bfd_link_info *info, if ((h->root.u.def.section->flags & SEC_ALLOC) != 0) { - htab->srelbss->size += sizeof (Elf32_External_Rela); + if (htab->is_vxworks) + htab->srelbss->size += sizeof (Elf32_External_Rela); + else + mips_elf_allocate_dynamic_relocations (dynobj, info, 1); h->needs_copy = 1; } + /* All relocations against this symbol that could have been made + dynamic will now refer to the local copy instead. */ + hmips->possibly_dynamic_relocs = 0; + return _bfd_elf_adjust_dynamic_copy (h, htab->sdynbss); } @@ -7808,6 +8283,7 @@ _bfd_mips_elf_always_size_sections (bfd *output_bfd, { asection *ri; struct mips_elf_link_hash_table *htab; + struct mips_htab_traverse_info hti; htab = mips_elf_hash_table (info); @@ -7816,10 +8292,13 @@ _bfd_mips_elf_always_size_sections (bfd *output_bfd, if (ri != NULL) bfd_set_section_size (output_bfd, ri, sizeof (Elf32_External_RegInfo)); - if (! (info->relocatable - || ! mips_elf_hash_table (info)->mips16_stubs_seen)) - mips_elf_link_hash_traverse (mips_elf_hash_table (info), - mips_elf_check_mips16_stubs, info); + hti.info = info; + hti.output_bfd = output_bfd; + hti.error = FALSE; + mips_elf_link_hash_traverse (mips_elf_hash_table (info), + mips_elf_check_symbols, &hti); + if (hti.error) + return FALSE; return TRUE; } @@ -7846,6 +8325,16 @@ mips_elf_lay_out_got (bfd *output_bfd, struct bfd_link_info *info) dynobj = elf_hash_table (info)->dynobj; g = htab->got_info; + /* Allocate room for the reserved entries. VxWorks always reserves + 3 entries; other objects only reserve 2 entries. */ + BFD_ASSERT (g->assigned_gotno == 0); + if (htab->is_vxworks) + htab->reserved_gotno = 3; + else + htab->reserved_gotno = 2; + g->local_gotno += htab->reserved_gotno; + g->assigned_gotno = htab->reserved_gotno; + /* Replace entries for indirect and warning symbols with entries for the target symbol. */ if (!mips_elf_resolve_final_got_entries (g)) @@ -7913,7 +8402,7 @@ mips_elf_lay_out_got (bfd *output_bfd, struct bfd_link_info *info) /* Each VxWorks GOT entry needs an explicit relocation. */ unsigned int count; - count = g->global_gotno + g->local_gotno - MIPS_RESERVED_GOTNO (info); + count = g->global_gotno + g->local_gotno - htab->reserved_gotno; if (count) mips_elf_allocate_dynamic_relocations (dynobj, info, count); } @@ -8023,7 +8512,7 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, struct bfd_link_info *info) { bfd *dynobj; - asection *s; + asection *s, *sreldyn; bfd_boolean reltext; struct mips_elf_link_hash_table *htab; @@ -8043,7 +8532,22 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, s->contents = (bfd_byte *) ELF_DYNAMIC_INTERPRETER (output_bfd); } - } + + /* Create a symbol for the PLT, if we know that we are using it. */ + if (htab->splt && htab->splt->size > 0 && htab->root.hplt == NULL) + { + struct elf_link_hash_entry *h; + + BFD_ASSERT (htab->use_plts_and_copy_relocs); + + h = _bfd_elf_define_linkage_sym (dynobj, info, htab->splt, + "_PROCEDURE_LINKAGE_TABLE_"); + htab->root.hplt = h; + if (h == NULL) + return FALSE; + h->type = STT_FUNC; + } + } /* Allocate space for global sym dynamic relocs. */ elf_link_hash_traverse (&htab->root, allocate_dynrelocs, (PTR) info); @@ -8117,11 +8621,18 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, else if (SGI_COMPAT (output_bfd) && CONST_STRNEQ (name, ".compact_rel")) s->size += mips_elf_hash_table (info)->compact_rel_size; + else if (s == htab->splt) + { + /* If the last PLT entry has a branch delay slot, allocate + room for an extra nop to fill the delay slot. */ + if (!htab->is_vxworks && s->size > 0) + s->size += 4; + } else if (! CONST_STRNEQ (name, ".init") && s != htab->sgot && s != htab->sgotplt - && s != htab->splt - && s != htab->sstubs) + && s != htab->sstubs + && s != htab->sdynbss) { /* It's not one of our sections, so don't allocate space. */ continue; @@ -8185,11 +8696,12 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_PLTGOT, 0)) return FALSE; + sreldyn = mips_elf_rel_dyn_section (info, FALSE); if (htab->is_vxworks) { /* VxWorks uses .rela.dyn instead of .rel.dyn. It does not use any of the DT_MIPS_* tags. */ - if (mips_elf_rel_dyn_section (info, FALSE)) + if (sreldyn && sreldyn->size > 0) { if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_RELA, 0)) return FALSE; @@ -8200,21 +8712,10 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_RELAENT, 0)) return FALSE; } - if (htab->splt->size > 0) - { - if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_PLTREL, 0)) - return FALSE; - - if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_JMPREL, 0)) - return FALSE; - - if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_PLTRELSZ, 0)) - return FALSE; - } } else { - if (mips_elf_rel_dyn_section (info, FALSE)) + if (sreldyn && sreldyn->size > 0) { if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_REL, 0)) return FALSE; @@ -8257,6 +8758,20 @@ _bfd_mips_elf_size_dynamic_sections (bfd *output_bfd, && !MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_MIPS_OPTIONS, 0)) return FALSE; } + if (htab->splt->size > 0) + { + if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_PLTREL, 0)) + return FALSE; + + if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_JMPREL, 0)) + return FALSE; + + if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_PLTRELSZ, 0)) + return FALSE; + + if (! MIPS_ELF_ADD_DYNAMIC_ENTRY (info, DT_MIPS_PLTGOT, 0)) + return FALSE; + } if (htab->is_vxworks && !elf_vxworks_add_dynamic_entries (output_bfd, info)) return FALSE; @@ -8651,6 +9166,68 @@ _bfd_mips_elf_relocate_section (bfd *output_bfd, struct bfd_link_info *info, return TRUE; } +/* A function that iterates over each entry in la25_stubs and fills + in the code for each one. DATA points to a mips_htab_traverse_info. */ + +static int +mips_elf_create_la25_stub (void **slot, void *data) +{ + struct mips_htab_traverse_info *hti; + struct mips_elf_link_hash_table *htab; + struct mips_elf_la25_stub *stub; + asection *s; + bfd_byte *loc; + bfd_vma offset, target, target_high, target_low; + + stub = (struct mips_elf_la25_stub *) *slot; + hti = (struct mips_htab_traverse_info *) data; + htab = mips_elf_hash_table (hti->info); + + /* Create the section contents, if we haven't already. */ + s = stub->stub_section; + loc = s->contents; + if (loc == NULL) + { + loc = bfd_malloc (s->size); + if (loc == NULL) + { + hti->error = TRUE; + return FALSE; + } + s->contents = loc; + } + + /* Work out where in the section this stub should go. */ + offset = stub->offset; + + /* Work out the target address. */ + target = (stub->h->root.root.u.def.section->output_section->vma + + stub->h->root.root.u.def.section->output_offset + + stub->h->root.root.u.def.value); + target_high = ((target + 0x8000) >> 16) & 0xffff; + target_low = (target & 0xffff); + + if (stub->stub_section != htab->strampoline) + { + /* This is a simple LUI/ADIDU stub. Zero out the beginning + of the section and write the two instructions at the end. */ + memset (loc, 0, offset); + loc += offset; + bfd_put_32 (hti->output_bfd, LA25_LUI (target_high), loc); + bfd_put_32 (hti->output_bfd, LA25_ADDIU (target_low), loc + 4); + } + else + { + /* This is trampoline. */ + loc += offset; + bfd_put_32 (hti->output_bfd, LA25_LUI (target_high), loc); + bfd_put_32 (hti->output_bfd, LA25_J (target), loc + 4); + bfd_put_32 (hti->output_bfd, LA25_ADDIU (target_low), loc + 8); + bfd_put_32 (hti->output_bfd, 0, loc + 12); + } + return TRUE; +} + /* If NAME is one of the special IRIX6 symbols defined by the linker, adjust it appropriately now. */ @@ -8722,8 +9299,76 @@ _bfd_mips_elf_finish_dynamic_symbol (bfd *output_bfd, dynobj = elf_hash_table (info)->dynobj; hmips = (struct mips_elf_link_hash_entry *) h; - if (h->plt.offset != MINUS_ONE) + BFD_ASSERT (!htab->is_vxworks); + + if (h->plt.offset != MINUS_ONE && hmips->no_fn_stub) + { + /* We've decided to create a PLT entry for this symbol. */ + bfd_byte *loc; + bfd_vma header_address, plt_index, got_address; + bfd_vma got_address_high, got_address_low, load; + const bfd_vma *plt_entry; + + BFD_ASSERT (htab->use_plts_and_copy_relocs); + BFD_ASSERT (h->dynindx != -1); + BFD_ASSERT (htab->splt != NULL); + BFD_ASSERT (h->plt.offset <= htab->splt->size); + BFD_ASSERT (!h->def_regular); + + /* Calculate the address of the PLT header. */ + header_address = (htab->splt->output_section->vma + + htab->splt->output_offset); + + /* Calculate the index of the entry. */ + plt_index = ((h->plt.offset - htab->plt_header_size) + / htab->plt_entry_size); + + /* Calculate the address of the .got.plt entry. */ + got_address = (htab->sgotplt->output_section->vma + + htab->sgotplt->output_offset + + (2 + plt_index) * MIPS_ELF_GOT_SIZE (dynobj)); + got_address_high = ((got_address + 0x8000) >> 16) & 0xffff; + got_address_low = got_address & 0xffff; + + /* Initially point the .got.plt entry at the PLT header. */ + loc = (htab->sgotplt->contents + + (2 + plt_index) * MIPS_ELF_GOT_SIZE (dynobj)); + if (ABI_64_P (output_bfd)) + bfd_put_64 (output_bfd, header_address, loc); + else + bfd_put_32 (output_bfd, header_address, loc); + + /* Find out where the .plt entry should go. */ + loc = htab->splt->contents + h->plt.offset; + + /* Pick the load opcode. */ + load = MIPS_ELF_LOAD_WORD (output_bfd); + + /* Fill in the PLT entry itself. */ + plt_entry = mips_exec_plt_entry; + bfd_put_32 (output_bfd, plt_entry[0] | got_address_high, loc); + bfd_put_32 (output_bfd, plt_entry[1] | got_address_low | load, loc + 4); + bfd_put_32 (output_bfd, plt_entry[2] | got_address_low, loc + 8); + bfd_put_32 (output_bfd, plt_entry[3], loc + 12); + + /* Emit an R_MIPS_JUMP_SLOT relocation against the .got.plt entry. */ + mips_elf_output_dynamic_relocation (output_bfd, htab->srelplt, + plt_index, h->dynindx, + R_MIPS_JUMP_SLOT, got_address); + + /* We distinguish between PLT entries and lazy-binding stubs by + giving the former an st_other value of STO_MIPS_PLT. Set the + flag and leave the value if there are any relocations in the + binary where pointer equality matters. */ + sym->st_shndx = SHN_UNDEF; + if (h->pointer_equality_needed) + sym->st_other = STO_MIPS_PLT; + else + sym->st_value = 0; + } + else if (h->plt.offset != MINUS_ONE) { + /* We've decided to create a lazy-binding stub. */ bfd_byte stub[MIPS_FUNCTION_STUB_BIG_SIZE]; /* This symbol has a stub. Set it up. */ @@ -8910,6 +9555,23 @@ _bfd_mips_elf_finish_dynamic_symbol (bfd *output_bfd, } } + /* Emit a copy reloc, if needed. */ + if (h->needs_copy) + { + asection *s; + bfd_vma symval; + + BFD_ASSERT (h->dynindx != -1); + BFD_ASSERT (htab->use_plts_and_copy_relocs); + + s = mips_elf_rel_dyn_section (info, FALSE); + symval = (h->root.u.def.section->output_section->vma + + h->root.u.def.section->output_offset + + h->root.u.def.value); + mips_elf_output_dynamic_relocation (output_bfd, s, s->reloc_count++, + h->dynindx, R_MIPS_COPY, symval); + } + /* Handle the IRIX6-specific symbols. */ if (IRIX_COMPAT (output_bfd) == ict_irix6) mips_elf_irix6_finish_dynamic_symbol (output_bfd, name, sym); @@ -9120,6 +9782,47 @@ _bfd_mips_vxworks_finish_dynamic_symbol (bfd *output_bfd, return TRUE; } +/* Write out a plt0 entry to the beginning of .plt. */ + +static void +mips_finish_exec_plt (bfd *output_bfd, struct bfd_link_info *info) +{ + bfd_byte *loc; + bfd_vma gotplt_value, gotplt_value_high, gotplt_value_low; + static const bfd_vma *plt_entry; + struct mips_elf_link_hash_table *htab; + + htab = mips_elf_hash_table (info); + if (ABI_64_P (output_bfd)) + plt_entry = mips_n64_exec_plt0_entry; + else if (ABI_N32_P (output_bfd)) + plt_entry = mips_n32_exec_plt0_entry; + else + plt_entry = mips_o32_exec_plt0_entry; + + /* Calculate the value of .got.plt. */ + gotplt_value = (htab->sgotplt->output_section->vma + + htab->sgotplt->output_offset); + gotplt_value_high = ((gotplt_value + 0x8000) >> 16) & 0xffff; + gotplt_value_low = gotplt_value & 0xffff; + + /* The PLT sequence is not safe for N64 if .got.plt's address can + not be loaded in two instructions. */ + BFD_ASSERT ((gotplt_value & ~(bfd_vma) 0x7fffffff) == 0 + || ~(gotplt_value | 0x7fffffff) == 0); + + /* Install the PLT header. */ + loc = htab->splt->contents; + bfd_put_32 (output_bfd, plt_entry[0] | gotplt_value_high, loc); + bfd_put_32 (output_bfd, plt_entry[1] | gotplt_value_low, loc + 4); + bfd_put_32 (output_bfd, plt_entry[2] | gotplt_value_low, loc + 8); + bfd_put_32 (output_bfd, plt_entry[3], loc + 12); + bfd_put_32 (output_bfd, plt_entry[4], loc + 16); + bfd_put_32 (output_bfd, plt_entry[5], loc + 20); + bfd_put_32 (output_bfd, plt_entry[6], loc + 24); + bfd_put_32 (output_bfd, plt_entry[7], loc + 28); +} + /* Install the PLT header for a VxWorks executable and finalize the contents of .rela.plt.unloaded. */ @@ -9275,21 +9978,13 @@ _bfd_mips_elf_finish_dynamic_sections (bfd *output_bfd, break; case DT_PLTGOT: - name = ".got"; - if (htab->is_vxworks) - { - /* _GLOBAL_OFFSET_TABLE_ is defined to be the beginning - of the ".got" section in DYNOBJ. */ - s = bfd_get_section_by_name (dynobj, name); - BFD_ASSERT (s != NULL); - dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; - } - else - { - s = bfd_get_section_by_name (output_bfd, name); - BFD_ASSERT (s != NULL); - dyn.d_un.d_ptr = s->vma; - } + s = htab->sgot; + dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; + break; + + case DT_MIPS_PLTGOT: + s = htab->sgotplt; + dyn.d_un.d_ptr = s->output_section->vma + s->output_offset; break; case DT_MIPS_RLD_VERSION: @@ -9355,7 +10050,7 @@ _bfd_mips_elf_finish_dynamic_sections (bfd *output_bfd, break; case DT_MIPS_HIPAGENO: - dyn.d_un.d_val = g->local_gotno - MIPS_RESERVED_GOTNO (info); + dyn.d_un.d_val = g->local_gotno - htab->reserved_gotno; break; case DT_MIPS_RLD_MAP: @@ -9376,18 +10071,21 @@ _bfd_mips_elf_finish_dynamic_sections (bfd *output_bfd, break; case DT_PLTREL: - BFD_ASSERT (htab->is_vxworks); - dyn.d_un.d_val = DT_RELA; + BFD_ASSERT (htab->use_plts_and_copy_relocs); + if (htab->is_vxworks) + dyn.d_un.d_val = DT_RELA; + else + dyn.d_un.d_val = DT_REL; break; case DT_PLTRELSZ: - BFD_ASSERT (htab->is_vxworks); + BFD_ASSERT (htab->use_plts_and_copy_relocs); dyn.d_un.d_val = htab->srelplt->size; break; case DT_JMPREL: - BFD_ASSERT (htab->is_vxworks); - dyn.d_un.d_val = (htab->srelplt->output_section->vma + BFD_ASSERT (htab->use_plts_and_copy_relocs); + dyn.d_un.d_ptr = (htab->srelplt->output_section->vma + htab->srelplt->output_offset); break; @@ -9615,12 +10313,20 @@ _bfd_mips_elf_finish_dynamic_sections (bfd *output_bfd, } } - if (htab->is_vxworks && htab->splt->size > 0) + if (htab->splt && htab->splt->size > 0) { - if (info->shared) - mips_vxworks_finish_shared_plt (output_bfd, info); + if (htab->is_vxworks) + { + if (info->shared) + mips_vxworks_finish_shared_plt (output_bfd, info); + else + mips_vxworks_finish_exec_plt (output_bfd, info); + } else - mips_vxworks_finish_exec_plt (output_bfd, info); + { + BFD_ASSERT (!info->shared); + mips_finish_exec_plt (output_bfd, info); + } } return TRUE; } @@ -10201,11 +10907,16 @@ _bfd_mips_elf_copy_indirect_symbol (struct bfd_link_info *info, _bfd_elf_link_hash_copy_indirect (info, dir, ind); + dirmips = (struct mips_elf_link_hash_entry *) dir; + indmips = (struct mips_elf_link_hash_entry *) ind; + /* Any absolute non-dynamic relocations against an indirect or weak + definition will be against the target symbol. */ + if (indmips->has_static_relocs) + dirmips->has_static_relocs = TRUE; + if (ind->root.type != bfd_link_hash_indirect) return; - dirmips = (struct mips_elf_link_hash_entry *) dir; - indmips = (struct mips_elf_link_hash_entry *) ind; dirmips->possibly_dynamic_relocs += indmips->possibly_dynamic_relocs; if (indmips->readonly_reloc) dirmips->readonly_reloc = TRUE; @@ -10215,6 +10926,8 @@ _bfd_mips_elf_copy_indirect_symbol (struct bfd_link_info *info, dirmips->global_got_area = indmips->global_got_area; if (indmips->global_got_area < GGA_NONE) indmips->global_got_area = GGA_NONE; + if (indmips->has_nonpic_branches) + dirmips->has_nonpic_branches = TRUE; if (dirmips->tls_type == 0) dirmips->tls_type = indmips->tls_type; @@ -10684,6 +11397,7 @@ _bfd_mips_elf_link_hash_table_create (bfd *abfd) ret->use_rld_obj_head = FALSE; ret->rld_value = 0; ret->mips16_stubs_seen = FALSE; + ret->use_plts_and_copy_relocs = FALSE; ret->is_vxworks = FALSE; ret->small_data_overflow_reported = FALSE; ret->srelbss = NULL; @@ -10699,6 +11413,9 @@ _bfd_mips_elf_link_hash_table_create (bfd *abfd) ret->plt_entry_size = 0; ret->lazy_stub_count = 0; ret->function_stub_size = 0; + ret->strampoline = NULL; + ret->la25_stubs = NULL; + ret->add_stub_section = NULL; return &ret->root.root; } @@ -10716,10 +11433,20 @@ _bfd_mips_vxworks_link_hash_table_create (bfd *abfd) struct mips_elf_link_hash_table *htab; htab = (struct mips_elf_link_hash_table *) ret; - htab->is_vxworks = 1; + htab->use_plts_and_copy_relocs = TRUE; + htab->is_vxworks = TRUE; } return ret; } + +/* A function that the linker calls if we are allowed to use PLTs + and copy relocs. */ + +void +_bfd_mips_elf_use_plts_and_copy_relocs (struct bfd_link_info *info) +{ + mips_elf_hash_table (info)->use_plts_and_copy_relocs = TRUE; +} /* We need to use a special link routine to handle the .reginfo and the .mdebug sections. We need to merge all instances of these @@ -10734,6 +11461,7 @@ _bfd_mips_elf_final_link (bfd *abfd, struct bfd_link_info *info) asection *rtproc_sec; Elf32_RegInfo reginfo; struct ecoff_debug_info debug; + struct mips_htab_traverse_info hti; const struct elf_backend_data *bed = get_elf_backend_data (abfd); const struct ecoff_debug_swap *swap = bed->elf_backend_ecoff_debug_swap; HDRR *symhdr = &debug.symbolic_header; @@ -10761,6 +11489,14 @@ _bfd_mips_elf_final_link (bfd *abfd, struct bfd_link_info *info) if (!mips_elf_sort_hash_table (abfd, info)) return FALSE; + /* Create any scheduled LA25 stubs. */ + hti.info = info; + hti.output_bfd = abfd; + hti.error = FALSE; + htab_traverse (htab->la25_stubs, mips_elf_create_la25_stub, &hti); + if (hti.error) + return FALSE; + /* Get a value for the GP register. */ if (elf_gp (abfd) == 0) { @@ -11676,11 +12412,9 @@ _bfd_mips_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd) new_flags &= ~EF_MIPS_UCODE; old_flags &= ~EF_MIPS_UCODE; - /* Don't care about the PIC flags from dynamic objects; they are - PIC by design. */ - if ((new_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0 - && (ibfd->flags & DYNAMIC) != 0) - new_flags &= ~ (EF_MIPS_PIC | EF_MIPS_CPIC); + /* DSOs should only be linked with CPIC code. */ + if ((ibfd->flags & DYNAMIC) != 0) + new_flags |= EF_MIPS_PIC | EF_MIPS_CPIC; if (new_flags == old_flags) return TRUE; @@ -11712,7 +12446,7 @@ _bfd_mips_elf_merge_private_bfd_data (bfd *ibfd, bfd *obfd) != ((old_flags & (EF_MIPS_PIC | EF_MIPS_CPIC)) != 0)) { (*_bfd_error_handler) - (_("%B: warning: linking PIC files with non-PIC files"), + (_("%B: warning: linking abicalls files with non-abicalls files"), ibfd); ok = TRUE; } @@ -11923,6 +12657,10 @@ _bfd_mips_elf_get_target_dtag (bfd_vma dtag) return "DT_MIPS_GP_VALUE"; case DT_MIPS_AUX_DYNAMIC: return "DT_MIPS_AUX_DYNAMIC"; + case DT_MIPS_PLTGOT: + return "DT_MIPS_PLTGOT"; + case DT_MIPS_RWPLT: + return "DT_MIPS_RWPLT"; } } @@ -12057,3 +12795,30 @@ _bfd_mips_elf_common_definition (Elf_Internal_Sym *sym) || sym->st_shndx == SHN_MIPS_ACOMMON || sym->st_shndx == SHN_MIPS_SCOMMON); } + +/* Return address for Ith PLT stub in section PLT, for relocation REL + or (bfd_vma) -1 if it should not be included. */ + +bfd_vma +_bfd_mips_elf_plt_sym_val (bfd_vma i, const asection *plt, + const arelent *rel ATTRIBUTE_UNUSED) +{ + return (plt->vma + + 4 * ARRAY_SIZE (mips_o32_exec_plt0_entry) + + i * 4 * ARRAY_SIZE (mips_exec_plt_entry)); +} + +void +_bfd_mips_post_process_headers (bfd *abfd, struct bfd_link_info *link_info) +{ + struct mips_elf_link_hash_table *htab; + Elf_Internal_Ehdr *i_ehdrp; + + i_ehdrp = elf_elfheader (abfd); + if (link_info) + { + htab = mips_elf_hash_table (link_info); + if (htab->use_plts_and_copy_relocs && !htab->is_vxworks) + i_ehdrp->e_ident[EI_ABIVERSION] = 1; + } +} |