To support IBT in Intel Control-flow Enforcement Technology (CET)
instructions:
https://software.intel.com/sites/default/files/managed/4d/2a/control-flow-enforcement-technology-preview.pdf
#define GNU_PROPERTY_X86_FEATURE_1_AND 0xc0000002
#define GNU_PROPERTY_X86_FEATURE_1_IBT (1U << 0)
are added to GNU program properties to indicate that all executable
sections are compatible with IBT when ENDBR instruction starts each
valid target where an indirect branch instruction can land.
GNU_PROPERTY_X86_FEATURE_1_IBT is set on output only if it is set on
all relocatable inputs.
The followings changes are made to the Procedure Linkage Table (PLT):
1. For 64-bit x86-64, PLT is changed to
PLT0: push GOT[1]
bnd jmp *GOT[2]
nop
...
PLTn: endbr64
push namen_reloc_index
bnd jmp PLT0
together with the second PLT section:
PLTn: endbr64
bnd jmp *GOT[namen_index]
nop
BND prefix is also added so that IBT-enabled PLT is compatible with MPX.
2. For 32-bit x86-64 (x32) and i386, PLT is changed to
PLT0: push GOT[1]
jmp *GOT[2]
nop
...
PLTn: endbr64 # endbr32 for i386.
push namen_reloc_index
jmp PLT0
together with the second PLT section:
PLTn: endbr64 # endbr32 for i386.
jmp *GOT[namen_index]
nop
BND prefix isn't used since MPX isn't supported on x32 and BND registers
aren't used in parameter passing on i386.
GOT is an array of addresses. Initially, GOT[namen_index] is filled
with the address of the ENDBR instruction of the corresponding entry
in the first PLT section. The function, namen, is called via the
ENDBR instruction in the second PLT entry. GOT[namen_index] is updated
to the actual address of the function, namen, at run-time.
2 linker command line options are added:
1. -z ibtplt: Generate IBT-enabled PLT.
2. -z ibt: Generate GNU_PROPERTY_X86_FEATURE_1_IBT in GNU program
properties as well as IBT-enabled PLT.
bfd/
* elf32-i386.c (elf_i386_lazy_ibt_plt0_entry): New.
(elf_i386_lazy_ibt_plt_entry): Likewise.
(elf_i386_pic_lazy_ibt_plt0_entry): Likewise.
(elf_i386_non_lazy_ibt_plt_entry): Likewise.
(elf_i386_pic_non_lazy_ibt_plt_entry): Likewise.
(elf_i386_eh_frame_lazy_ibt_plt): Likewise.
(elf_i386_lazy_plt_layout): Likewise.
(elf_i386_non_lazy_plt_layout): Likewise.
(elf_i386_link_hash_entry): Add plt_second.
(elf_i386_link_hash_table): Add plt_second and
plt_second_eh_frame.
(elf_i386_allocate_dynrelocs): Use the second PLT if needed.
(elf_i386_size_dynamic_sections): Use .plt.got unwind info for
the second PLT. Check the second PLT.
(elf_i386_relocate_section): Use the second PLT to resolve
PLT reference if needed.
(elf_i386_finish_dynamic_symbol): Fill and use the second PLT if
needed.
(elf_i386_finish_dynamic_sections): Set sh_entsize on the
second PLT. Generate unwind info for the second PLT.
(elf_i386_plt_type): Add plt_second.
(elf_i386_get_synthetic_symtab): Support the second PLT.
(elf_i386_parse_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND.
(elf_i386_merge_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND. If info->ibt is set, turn
on GNU_PROPERTY_X86_FEATURE_1_IBT
(elf_i386_link_setup_gnu_properties): If info->ibt is set,
turn on GNU_PROPERTY_X86_FEATURE_1_IBT. Use IBT-enabled PLT
for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
is set on all relocatable inputs.
* elf64-x86-64.c (elf_x86_64_lazy_ibt_plt_entry): New.
(elf_x32_lazy_ibt_plt_entry): Likewise.
(elf_x86_64_non_lazy_ibt_plt_entry): Likewise.
(elf_x32_non_lazy_ibt_plt_entry): Likewise.
(elf_x86_64_eh_frame_lazy_ibt_plt): Likewise.
(elf_x32_eh_frame_lazy_ibt_plt): Likewise.
(elf_x86_64_lazy_ibt_plt): Likewise.
(elf_x32_lazy_ibt_plt): Likewise.
(elf_x86_64_non_lazy_ibt_plt): Likewise.
(elf_x32_non_lazy_ibt_plt): Likewise.
(elf_x86_64_get_synthetic_symtab): Support the second PLT.
(elf_x86_64_parse_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND.
(elf_x86_64_merge_gnu_properties): Support
GNU_PROPERTY_X86_FEATURE_1_AND. If info->ibt is set, turn
on GNU_PROPERTY_X86_FEATURE_1_IBT
(elf_x86_64_link_setup_gnu_properties): If info->ibt is set,
turn on GNU_PROPERTY_X86_FEATURE_1_IBT. Use IBT-enabled PLT
for info->ibtplt, info->ibt or GNU_PROPERTY_X86_FEATURE_1_IBT
is set on all relocatable inputs.
binutils/
* readelf.c (decode_x86_feature): New.
(print_gnu_property_note): Call decode_x86_feature on
GNU_PROPERTY_X86_FEATURE_1_AND.
* testsuite/binutils-all/i386/empty.d: New file.
* testsuite/binutils-all/i386/empty.s: Likewise.
* testsuite/binutils-all/i386/ibt.d: Likewise.
* testsuite/binutils-all/i386/ibt.s: Likewise.
* testsuite/binutils-all/x86-64/empty-x32.d: Likewise.
* testsuite/binutils-all/x86-64/empty.d: Likewise.
* testsuite/binutils-all/x86-64/empty.s: Likewise.
* testsuite/binutils-all/x86-64/ibt-x32.d: Likewise.
* testsuite/binutils-all/x86-64/ibt.d: Likewise.
* testsuite/binutils-all/x86-64/ibt.s: Likewise.
include/
* bfdlink.h (bfd_link_info): Add ibtplt and ibt.
* elf/common.h (GNU_PROPERTY_X86_FEATURE_1_AND): New.
(GNU_PROPERTY_X86_FEATURE_1_IBT): Likewise.
ld/
* Makefile.am (ELF_X86_DEPS): Add $(srcdir)/emulparams/cet.sh.
* Makefile.in: Regenerated.
* NEWS: Mention GNU_PROPERTY_X86_FEATURE_1_IBT, -z ibtplt
and -z ibt.
* emulparams/cet.sh: New file.
* testsuite/ld-i386/ibt-plt-1.d: Likewise.
* testsuite/ld-i386/ibt-plt-1.s: Likewise.
* testsuite/ld-i386/ibt-plt-2.s: Likewise.
* testsuite/ld-i386/ibt-plt-2a.d: Likewise.
* testsuite/ld-i386/ibt-plt-2b.d: Likewise.
* testsuite/ld-i386/ibt-plt-2c.d: Likewise.
* testsuite/ld-i386/ibt-plt-2d.d: Likewise.
* testsuite/ld-i386/ibt-plt-3.s: Likewise.
* testsuite/ld-i386/ibt-plt-3a.d: Likewise.
* testsuite/ld-i386/ibt-plt-3b.d: Likewise.
* testsuite/ld-i386/ibt-plt-3c.d: Likewise.
* testsuite/ld-i386/ibt-plt-3d.d: Likewise.
* testsuite/ld-i386/plt-main-ibt.dd: Likewise.
* testsuite/ld-i386/plt-pie-ibt.dd: Likewise.
* testsuite/ld-i386/property-x86-empty.s: Likewise.
* testsuite/ld-i386/property-x86-ibt.s: Likewise.
* testsuite/ld-i386/property-x86-ibt1a.d: Likewise.
* testsuite/ld-i386/property-x86-ibt1b.d: Likewise.
* testsuite/ld-i386/property-x86-ibt2.d: Likewise.
* testsuite/ld-i386/property-x86-ibt3a.d: Likewise.
* testsuite/ld-i386/property-x86-ibt3b.d: Likewise.
* testsuite/ld-i386/property-x86-ibt4.d: Likewise.
* testsuite/ld-i386/property-x86-ibt5.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-1.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-2.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-2a-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2a.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2b-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2b.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-2d.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3.s: Likewise.
* testsuite/ld-x86-64/ibt-plt-3a-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3a.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3b-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3b.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3c.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d-x32.d: Likewise.
* testsuite/ld-x86-64/ibt-plt-3d.d: Likewise.
* testsuite/ld-x86-64/plt-main-ibt-now.rd: Likewise.
* testsuite/ld-x86-64/plt-main-ibt-x32.dd: Likewise.
* testsuite/ld-x86-64/plt-main-ibt.dd: Likewise.
* testsuite/ld-x86-64/property-x86-empty.s: Likewise.
* testsuite/ld-x86-64/property-x86-ibt.s: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1a-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1a.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1b-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt1b.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt2-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt2.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3a-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3a.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3b-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt3b.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt4-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt4.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt5-x32.d: Likewise.
* testsuite/ld-x86-64/property-x86-ibt5.d: Likewise.
* emulparams/elf32_x86_64.sh: Source emulparams/cet.sh.
(TINY_READONLY_SECTION): Add .plt.sec.
* emulparams/elf_i386.sh: Likewise.
* emulparams/elf_x86_64.sh: Source emulparams/cet.sh.
* ld.texinfo: Document -z ibtplt and -z ibt.
* testsuite/ld-i386/i386.exp: Run IBT and IBT PLT tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-x86-64/pr21481b.S (check): Updated for x32.
Since the BFD section count may not be cleared for shared objects during
linking, we should check the DYNAMIC bit for input shared objects.
bfd/
PR ld/21626
* elf-properties.c (_bfd_elf_link_setup_gnu_properties): Check
the DYNAMIC bit instead of bfd_count_sections.
ld/
PR ld/21626
* testsuite/ld-i386/i386.exp: Run ld/21626 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
Since it is incorrect to convert
bnd call *foo@GOTPCREL(%rip)
to
bnd nop
call foo
this patch removes the "-z prefix-nop" option from x86 linker.
* emulparams/call_nop.sh: Remove -z prefix-nop.
* ld.texinfo: Likewise.
* testsuite/ld-i386/call3c.d: Check for linker error.
* testsuite/ld-x86-64/call1c.d: Likewise.
Verify that debug section is removed by garbage collection when there
is a .note.gnu.property section.
* testsuite/ld-i386/i386.exp: Run property-x86-4a and
property-x86-4b.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/property-x86-4a.d: New file.
* testsuite/ld-i386/property-x86-4a.s: Likewise.
* testsuite/ld-i386/property-x86-4b.d: Likewise.
* testsuite/ld-i386/property-x86-4b.s: Likewise.
* testsuite/ld-x86-64/property-x86-4a.d: Likewise.
* testsuite/ld-x86-64/property-x86-4a.s: Likewise.
* testsuite/ld-x86-64/property-x86-4b.d: Likewise.
* testsuite/ld-x86-64/property-x86-4b.s: Likewise.
If there are more than GNU property note in an input, we should merge
X86_ISA_1_USED and X86_ISA_1_NEEDED properties.
bfd/
* elf32-i386.c (elf_i386_parse_gnu_properties): Merge
GNU_PROPERTY_X86_ISA_1_USED and GNU_PROPERTY_X86_ISA_1_NEEDED
properties.
* elf64-x86-64.c (elf_x86_64_parse_gnu_properties): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Run property-x86-3.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/property-x86-3.d: New file.
* testsuite/ld-i386/property-x86-3.s: Likewise.
* testsuite/ld-x86-64/property-x86-3.d: Likewise.
* testsuite/ld-x86-64/property-x86-3.s: Likewise.
This patch partially reverses:
commit 25070364b0
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Sat May 16 07:00:21 2015 -0700
Don't generate PLT relocations for now binding
to support LD_AUDIT and LD_PROFILE with -z now. If there is an existing
GOT relocation, it is still used to avoid PLT relocation against the same
function symbol.
bfd/
* elf32-i386.c (elf_i386_allocate_dynrelocs): Partially revert
commit 25070364b0.
* elf64-x86-64.c (elf_x86_64_allocate_dynrelocs): Likewse.
ld/
* testsuite/ld-i386/plt-pic2.dd: Updated.
* testsuite/ld-i386/plt2.dd: Likewise.
* testsuite/ld-i386/plt2.rd: Likewise.
* testsuite/ld-i386/pr17689now.rd: Likewise.
* testsuite/ld-ifunc/ifunc-16-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-16-x86-64-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-i386-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-x86-64-now.d: Likewise.
* testsuite/ld-x86-64/bnd-branch-1-now.d: Likewise.
* testsuite/ld-x86-64/bnd-ifunc-2-now.d: Likewise.
* testsuite/ld-x86-64/bnd-plt-1-now.d: Likewise.
* testsuite/ld-x86-64/plt2.dd: Likewise.
* testsuite/ld-x86-64/plt2.rd: Likewise.
* testsuite/ld-x86-64/pr17689now.rd: Likewise.
* testsuite/ld-x86-64/pr21038b-now.d: Likewise.
* testsuite/ld-x86-64/pr21038c-now.d: Likewise.
On i386, the procedure linkage table (PLT) is used to
1. Call external function.
2. Call internal IFUNC function. The best implementation is selected
for the target processor at run-time.
3. Act as the canonical function address.
4. Support LD_AUDIT to audit external function calls.
5. Support LD_PROFILE to profile external function calls.
PLT looks like:
PLT0: push GOT[1]
jmp *GOT[2]
nop
PLT1: jmp *GOT[name1_index]
push name1_reloc_index
jmp PLT0
GOT is an array of addresses. Initially the GOT entry of name1 is
filled with the address of the "push name1_reloc_index" instruction.
The function, name1, is called via "jmp *GOT[name1]" in the PLT entry.
Even when lazy binding is disabled by "-z now", the PLT0 entry may
still be used with LD_AUDIT or LD_PROFILE if PLT entry is used for
canonical function address.
1. With lazy binding, when the external function, name1, is called the
first time, dynamic linker is called via PLT0 to update GOT[name1_index]
with the actual address of name1 and transfers control to name1
afterwards.
2. PLT is also used to call a local IFUNC function, name1, run-time
loader updates GOT[name1_index] when loading the module.
This patch
1. Remove PLT layout configurations from i386 backend_data.
2. Add generic, lay and non-lazy PLT layout configurations to i386
link_hash_table. Generic PLT layout includes the PLT entry templates,
information how to update the first instruction in PLT and PLT eh_frame
informaton, which are initialized in i386 setup_gnu_properties, based
on PIC and target selection. PLT section alignment is also set to PLT
entry size for non-NaCl/VxWorks target.
3. Remove elf_i386_create_dynamic_sections. create_dynamic_sections
isn't always called, but GOT relocations need GOT relocations. Instead,
create all i386 specific dynamic sections in i386 setup_gnu_properties,
which initializes elf.dynobj, so that i386 check_relocs can be simplified.
4. Rewrite elf_i386_get_synthetic_symtab to check PLT sections against
all dynamic relocations to support both lazy and non-lazy PLTs.
bfd/
* elf32-i386.c (PLT_ENTRY_SIZE): Renamed to ...
(LAZY_PLT_ENTRY_SIZE): This.
(NON_LAZY_PLT_ENTRY_SIZE): New.
(elf_i386_plt0_entry): Renamed to ...
(elf_i386_lazy_plt0_entry): This.
(elf_i386_plt_entry): Renamed to ...
(elf_i386_lazy_plt_entry): This.
(elf_i386_pic_plt0_entry): Renamed to ...
(elf_i386_pic_lazy_plt0_entry): This.
(elf_i386_pic_plt_entry): Renamed to ...
(elf_i386_pic_lazy_plt_entry): This.
(elf_i386_got_plt_entry): Renamed to ...
(elf_i386_non_lazy_plt_entry): This.
(elf_i386_pic_got_plt_entry): Renamed to ...
(elf_i386_pic_non_lazy_plt_entry): This.
(elf_i386_eh_frame_plt): Renamed to ...
(elf_i386_eh_frame_lazy_plt): This.
(elf_i386_eh_frame_plt_got): Renamed to ...
(elf_i386_eh_frame_non_lazy_plt): This.
(elf_i386_plt_layout): Renamed to ...
(elf_i386_lazy_plt_layout): This. Remove eh_frame_plt_got and
eh_frame_plt_got_size.
(elf_i386_non_lazy_plt_layout): New.
(elf_i386_plt_layout): Likewise.
(elf_i386_non_lazy_plt): Likewise.
(GET_PLT_ENTRY_SIZE): Removed.
(elf_i386_plt): Renamed to ...
(elf_i386_lazy_plt): This.
(elf_i386_backend_data): Remove plt. Rename is_vxworks to os.
(elf_i386_arch_bed): Updated.
(elf_i386_link_hash_table): Add plt, lazy_plt and non_lazy_plt.
(elf_i386_create_dynamic_sections): Removed.
(elf_i386_check_relocs): Don't check elf.dynobj. Don't call
_bfd_elf_create_ifunc_sections nor _bfd_elf_create_got_section.
(elf_i386_adjust_dynamic_symbol): Updated.
(elf_i386_allocate_dynrelocs): Updated. Pass 0 as PLT header
size to _bfd_elf_allocate_ifunc_dyn_relocs and don't allocate
size for PLT0 if there is no PLT0.
(elf_i386_size_dynamic_sections): Updated. Check whether GOT
output section is discarded only if GOT isn't empty.
(elf_i386_relocate_section): Updated. Properly get PLT index
if there is no PLT0.
(elf_i386_finish_dynamic_symbol): Updated. Don't fill the
second and third slots in the PLT entry if there is no PLT0.
(elf_i386_finish_dynamic_sections): Updated. Don't fill PLT0
if there is no PLT0. Set sh_entsize on the .plt.got section.
(elf_i386_nacl_plt): Forward declaration.
(elf_i386_get_plt_sym_val): Removed.
(elf_i386_get_synthetic_symtab): Rewrite to check PLT sections
against all dynamic relocations.
(elf_i386_link_setup_gnu_properties): New function.
(elf_backend_create_dynamic_sections): Updated.
(elf_backend_setup_gnu_properties): New.
(elf_i386_nacl_plt): Updated.
(elf_i386_nacl_arch_bed): Likewise.
(elf_i386_vxworks_arch_bed): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Add some -z now tests.
* testsuite/ld-i386/plt-pic2.dd: New file.
* testsuite/ld-i386/plt2.dd: Likewise.
* testsuite/ld-i386/plt2.rd: Likewise.
* testsuite/ld-i386/plt2.s: Likewise.
* testsuite/ld-ifunc/ifunc-16-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-2-i386-now.d: Likewise.
* testsuite/ld-ifunc/ifunc-2-local-i386-now.d: Likewise.
* testsuite/ld-ifunc/pr17154-i386-now.d: Likewise.
* testsuite/ld-i386/pr20830.d: Update the .plt.got section
with func@plt.
* testsuite/ld-i386/tls.exp: Add -Wl,--no-as-needed to
"TLS without PLT (1)" and "TLS without PLT (3)".
* testsuite/ld-x86-64/tls.exp: Add -Wl,--no-as-needed to
to "TLS without PLT (3)".
Check if GNU2 TLS really works before running GNU2 TLS tests.
* testsuite/ld-i386/tls.exp: Run GNU2 TLS tests only if there
is working GNU2 TLS support.
* testsuite/ld-x86-64/tls.exp: Likewise.
* testsuite/lib/ld-lib.exp (check_gnu2_tls_available): New proc.
x86, PLT relocation may contain R_386_TLS_DESC or R_X86_64_TLSDESC
even though there is no real PLT. We need to add DT_PLTRELSZ, DT_PLTREL
and DT_JMPREL if there is a .rel.plt/.rela.plt section.
bfd/
* elf32-i386.c (elf_i386_size_dynamic_sections): Alwasys add
DT_PLTRELSZ, DT_PLTREL and DT_JMPREL for .rel.plt section.
* elf64-x86-64.c (elf_x86_64_size_dynamic_sections): Alwasys
add DT_PLTRELSZ, DT_PLTREL and DT_JMPREL for .rela.plt section.
ld/
* testsuite/ld-i386/tlsdesc2.d: New test.
* testsuite/ld-x86-64/tlsdesc2.d: Likewise.
commit f129e49f4d
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Tue Jan 10 11:30:25 2017 -0800
Don't use elf_i386_eh_frame_plt directly
fixed i386 PLT eh_frame generation. Skip pr12570 tests since they are
for non-nacl targets.
* testsuite/ld-i386/pr12570a.d: Skip for nacl targets.
* testsuite/ld-i386/pr12570b.d: Likewise.
commit a27e437177
Author: Roland McGrath <roland@gnu.org>
Date: Thu Jul 28 22:35:15 2011 +0000
BFD vector for elf32-i386-nacl:
changed ELF_MAXPAGESIZE to 0x10000 for VxWorks. This patch fixes it
and updated testsuite/ld-i386/vxworks2.sd to add space for program
headers.
bfd/
PR ld/21425
* elf32-i386.c (ELF_MAXPAGESIZE): Set to 0x1000 for VxWorks.
ld/
PR ld/20815
* testsuite/ld-i386/vxworks2.sd: Add space for program headers.
When -static -E/--dynamic-list are passed to linker, linker may create
executable with dynamic sections which aren't supported by run-time.
We require --no-dynamic-linker together with -static -E/--dynamic-list
before adding dynamic symbol table to static executable.
bfd/
PR ld/19617
PR ld/21086
* elflink.c (elf_link_add_object_symbols): Require
--no-dynamic-linker with -E/--dynamic-list when creating
dynamic sections.
ld/
PR ld/19617
PR ld/21086
* testsuite/ld-elf/pr19617a.d: Pass --no-dynamic-linker to ld.
* testsuite/ld-elf/pr19617b.d: Likewise.
* testsuite/ld-elf/pr19617c.d: Likewise.
*testsuite/ld-i386/pr19636-4d.d: Likewise.
* testsuite/ld-elf/readelf.exp: Pass --no-dynamic-linker to ld
with --export-dynamic.
* testsuite/ld-elf/shared.exp: Pass --no-dynamic-linker to ld
with -E.
"lea foo@GOT, %reg" is OK in PIC since it only loads the GOT offset
into register, which can be used later with a GOT base register to
get the value in the GOT entry.
bfd/
PR ld/21168
* elf32-i386.c (elf_i386_relocate_section): Allow
"lea foo@GOT, %reg" in PIC.
ld/
PR ld/21168
* testsuite/ld-i386/i386.exp: Run pr21168.
* testsuite/ld-i386/pr21168a.c: New file.
* testsuite/ld-i386/pr21168b.S: Likewise.
bfd/
PR ld/20244
* elf32-i386.c (elf_i386_relocate_section): Properly get IFUNC
symbol name when reporting R_386_GOT32/R_386_GOT32X relocation
error against local IFUNC symbol without a base register for
PIC.
ld/
PR ld/20244
* testsuite/ld-i386/i386.exp: Run pr20244-4a, pr20244-4b and
pr20244-4c.
* testsuite/ld-i386/pr20244-4.s: New file.
* testsuite/ld-i386/pr20244-4a.d: Likewise.
* testsuite/ld-i386/pr20244-4b.d: Likewise.
* testsuite/ld-i386/pr20244-4c.d: Likewise.
When there are both PLT and GOT references to the same function symbol,
linker combines GOTPLT and GOT slots into a single GOT slot and create
an entry in .plt.got section for PLT access via the GOT slot. This
patch adds unwind info for .plt.got section.
bfd/
PR ld/20830
* elf32-i386.c (elf_i386_eh_frame_plt_got): New.
(PLT_GOT_FDE_LENGTH): Likewise.
(elf_i386_plt_layout): Add eh_frame_plt_got and
eh_frame_plt_got_size.
(elf_i386_plt): Updated.
(elf_i386_link_hash_table): Add plt_got_eh_frame.
(elf_i386_check_relocs): Create .eh_frame section for .plt.got.
(elf_i386_size_dynamic_sections): Allocate and initialize
.eh_frame section for .plt.got.
(elf_i386_finish_dynamic_sections): Adjust .eh_frame section for
.plt.got.
(elf_i386_nacl_plt): Add FIXME for eh_frame_plt_got and
eh_frame_plt_got_size.
* elf64-x86-64.c (elf_x86_64_eh_frame_plt_got): New.
(PLT_GOT_FDE_LENGTH): Likewise.
(elf_x86_64_backend_data): Add eh_frame_plt_got and
eh_frame_plt_got_size.
(elf_x86_64_arch_bed): Updated.
(elf_x86_64_bnd_arch_bed): Add FIXME for eh_frame_plt_got and
eh_frame_plt_got_size.
(elf_x86_64_nacl_arch_bed): Likewise.
(elf_x86_64_link_hash_table): Add plt_got_eh_frame.
(elf_x86_64_check_relocs): Create .eh_frame section for .plt.got.
(elf_x86_64_size_dynamic_sections): Allocate and initialize
.eh_frame section for .plt.got.
(elf_x86_64_finish_dynamic_sections): Adjust .eh_frame section
for .plt.got.
ld/
PR ld/20830
* testsuite/ld-i386/i386.exp: Run pr20830.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr20830.d: New file.
* testsuite/ld-i386/pr20830.s: Likewise.
* testsuite/ld-x86-64/pr20830.d: Likewise.
* testsuite/ld-x86-64/pr20830.s: Likewise.
Since linker tests were changed to use $CC, instead of $LD, we need
to pass -Wl,-R,tmpdir and -Wl,--as-needed to $CC.
* testsuite/ld-i386/i386.exp: Pass -Wl,-R,tmpdir to GCC driver.
* testsuite/ld-i386/tls.exp: Likewise.
PR ld/20815
bfd * elf.c (elf_modify_segment_map): Allow empty LOAD segments if
they contain the program headers.
(_bfd_elf_map_sections_to_segments): If the linker created the
PHDR segment then always attempt to include it in a LOAD segment.
(assign_file_positions_for_non_load_sections): Allow LOAD segments
to overlap PHDR segments.
(phdr_sorter): New function. Sorts program headers.
(assign_file_positions_except_relocs): Sort the program headers
before writing them out. Issue an error if the PHDR segment is
not covered by a LOAD segment, unless the backend allows it.
* elf-bfd.h (struct elf_backend_data): Add
elf_backend_allow_non_load_phdr.
* elfxx-target.h (elf_backend_allow_non_load_phdr): Provide
default definition that returns FALSE.
(elfNN_bed): Initialise the elf_backend_allow_non_load_phdr
field.
* elf64-hppa.c (elf64_hppa_allow_non_load_phdr): New function.
Returns TRUE.
(elf_backend_allow_non_load_phdr): Define.
* elf-m10300.c (_bfd_mn10300_elf_size_dynamic_sections): Do not
place the interpreter string into the .interp section if the
nointerp flag is set in the link info structure.
* elf32-arc.c (elf_arc_size_dynamic_sections): Likewise.
* elf32-score7.c (score_elf_final_link_relocate): Allow for the
_gp symbol not being part of the output.
binutils* readelf.c (process_program_headers): Check PT_LOAD and PT_PHDR
segments for validity.
ld * ld.texinfo: Note that PT_TLS can be used as a segment type.
* testsuite/ld-discard/discard.ld: Add space for program headers.
* testsuite/ld-elf/flags1.ld: Likewise.
* testsuite/ld-elf/maxpage3.t: Likewise.
* testsuite/ld-elf/noload-1.t: Likewise.
* testsuite/ld-elf/orphan.ld: Likewise.
* testsuite/ld-elf/overlay.t: Likewise.
* testsuite/ld-elf/pr14052.t: Likewise.
* testsuite/ld-elf/pr19539.t: Likewise.
* testsuite/ld-elf/provide-hidden-1.ld: Likewise.
* testsuite/ld-elf/provide-hidden-s.ld: Likewise.
* testsuite/ld-elf/weak-dyn-1.ld: Likewise.
* testsuite/ld-i386/pr19539.t: Likewise.
* testsuite/ld-scripts/defined.t: Likewise.
* testsuite/ld-scripts/defined6.t: Likewise.
* testsuite/ld-scripts/dynamic-sections.t: Likewise.
* testsuite/ld-scripts/empty-aligned.t: Likewise.
* testsuite/ld-scripts/provide-2.t: Likewise.
* testsuite/ld-scripts/provide-4.t: Likewise.
* testsuite/ld-vax-elf/plt-local.ld: Likewise.
* testsuite/ld-x86-64/pr19539.t: Likewise.
* testsuite/ld-elf/ehdr_start-missing.d: Do not initialise the
dynamic linker.
* testsuite/ld-elf/ehdr_start-weak.d: Likewise.
* testsuite/ld-elf/elf.exp (pr14170, pr17068): Likewise.
* testsuite/ld-elf/loadaddr1.d: Update expected readelf output.
* testsuite/ld-elf/noload-2.d: Likewise.
* testsuite/ld-powerpc/vxworks2.sd: Likewise.
* testsuite/ld-scripts/phdrs3a.d: Likewise.
* testsuite/ld-scripts/size-2.d: Likewise.
* testsuite/ld-elf/group.ld: Add program headers.
* testsuite/ld-elf/overlay.d: Skip for SPU.
* testsuite/ld-elf/flags1.d: Skip for RX.
* testsuite/ld-elf/pr19162.d: Skip for HPPA64.
* testsuite/ld-elf/pr19539.d: Skip for ALPHA.
* testsuite/ld-scripts/empty-orphan.t: Update program headers.
* testsuite/ld-scripts/size-2.t: Likewise.
On i386, IFUNC function must be called via PLT. Since PLT in PIC
object uses EBX register, R_386_PLT32 relocation must be used to
call IFUNC function even when IFUNC function is defined locally.
Linker should issue an error when R_386_PC32 relocation is used
to call IFUNC function.
Since PR ld/19784 tests doesn't use PLT relocation to local IFUNC
function, they are moved to the x86-64 test directory.
bfd/
PR ld/14961
PR ld/20515
* elf32-i386.c (elf_i386_check_relocs): Issue an error when
R_386_PC32 relocation is used to call IFUNC function in PIC
object.
ld/
PR ld/14961
PR ld/20515
* testsuite/ld-i386/i386.exp: Run pr20515.
* testsuite/ld-i386/pr20515.d: New file.
* testsuite/ld-i386/pr20515.s: Likewise.
* testsuite/ld-ifunc/ifunc-14a.s: Use R_386_PLT32 to call IFUNC
function.
* testsuite/ld-ifunc/ifunc-14c.s: Likewise.
* testsuite/ld-ifunc/ifunc-2-i386.s: Likewise.
* testsuite/ld-ifunc/ifunc-2-local-i386.s: Likewise.
* testsuite/ld-ifunc/ifunc.exp: Move PR ld/19784 tests to ...
* testsuite/ld-x86-64/x86-64.exp: Here.
* testsuite/ld-ifunc/pr19784a.c: Moved to ...
* testsuite/ld-x86-64/pr19784a.c: Here.
* testsuite/ld-ifunc/pr19784b.c: Moved to ...
* testsuite/ld-x86-64/pr19784b.c: Here.
* testsuite/ld-ifunc/pr19784c.c: Moved to ...
* testsuite/ld-x86-64/pr19784c.c: Here.
If the last parameter of a tcl function is "args" then it can take
zero or more arguments. Make use of this language feature in
run_ld_link_exec_tests.
* testsuite/lib/ld-lib.exp (run_ld_link_exec_tests): Replace
"targets_to_xfail" parameter with "args".
* testsuite/ld-elf/compress.exp: Remove empty list of xfails on
all calls to run_ld_link_exec_tests.
* testsuite/ld-elf/dwarf.exp: Likewise.
* testsuite/ld-elf/indirect.exp: Likewise.
* testsuite/ld-elf/wrap.exp: Likewise.
* testsuite/ld-i386/i386.exp: Likewise.
* testsuite/ld-i386/no-plt.exp: Likewise.
* testsuite/ld-i386/tls.exp: Likewise.
* testsuite/ld-ifunc/ifunc.exp: Likewise.
* testsuite/ld-pie/pie.exp: Likewise.
* testsuite/ld-plugin/lto.exp: Likewise.
* testsuite/ld-size/size.exp: Likewise.
* testsuite/ld-x86-64/mpx.exp: Likewise.
* testsuite/ld-x86-64/no-plt.exp: Likewise.
* testsuite/ld-x86-64/tls.exp: Likewise.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-elf/elf.exp: Likewise. Reorder args when providing
xfails and simplify lists.
* testsuite/ld-elf/shared.exp: Likewise.
Since x86 elf_*_check_relocs is called after all symbols have been
resolved, there is no need to check undefined symbols for relocations
against IFUNC symbols.
bfd/
* elf32-i386.c (elf_i386_check_relocs): Don't check undefined
symbols for relocations against IFUNC symbols.
* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
ld/
* testsuite/ld-i386/i386.exp: Run pr19636-2e-nacl.
* testsuite/ld-i386/pr19636-2e.d: Skip for NaCl targets.
Remove .rel.plt section.
* testsuite/ld-i386/pr19636-2e-nacl.d: New file.
Add the GOT base for R_386_GOT32/R_386_GOT32X relocations against IFUNC
symbols if there is no base register and disallow them for PIC.
bfd/
PR ld/20244
* elf32-i386.c (elf_i386_relocate_section): Add the .got.plt
section address for R_386_GOT32/R_386_GOT32X relocations against
IFUNC symbols if there is no base register and return error for
PIC.
ld/
PR ld/20244
* testsuite/ld-i386/i386.exp: Run pr20244-2a, pr20244-2b,
pr20244-2c and pr20244-2d.
* testsuite/ld-i386/no-plt.exp: Run pr20244-3a and pr20244-3b.
* testsuite/ld-i386/pr20244-2.s: New file.
* testsuite/ld-i386/pr20244-2a.d: Likewise.
* testsuite/ld-i386/pr20244-2b.d: Likewise.
* testsuite/ld-i386/pr20244-2c.d: Likewise.
* testsuite/ld-i386/pr20244-2d.d: Likewise.
* testsuite/ld-i386/pr20244-3a.c: Likewise.
* testsuite/ld-i386/pr20244-3b.S: Likewise.
* testsuite/ld-i386/pr20244-3c.S: Likewise.
* testsuite/ld-i386/pr20244-3d.S: Likewise.
When relocating R_386_GOT32 in "op $0, bar@GOT", we shouldn't subtract
GOT base without a base register and we should disallow it without a
base register for PIC.
bfd/
PR ld/20244
* elf32-i386.c (elf_i386_relocate_section): When relocating
R_386_GOT32, return error without a base register for PIC and
subtract the .got.plt section address only with a base register.
ld/
PR ld/20244
* testsuite/ld-i386/i386.exp: Run pr20244-1a and pr20244-1b.
* testsuite/ld-i386/pr20244-1.s: New file.
* testsuite/ld-i386/pr20244-1a.d: Likewise.
* testsuite/ld-i386/pr20244-1b.d: Likewise.
* testsuite/ld-i386/pr20244-1c.d: Likewise.
To call an external function, the direct branch to the PLT entry can be
replaced by an indirect branch via the GOT slot, which is similar to the
first instruction in the PLT slot. Instead using the PLT slot as function
address, the function address is retrieved from the GOT slot. The
R_386_GOT32X relocation can be used to compute the address of the symbol’s
GOT entry without base register when PIC is disabled. In non-PIC
executable,
call/jmp *func@GOT
should be used for indirect branch via the GOT slot and
movl func@GOT, %eax
should be used to load function address. Unlike PIC case, no register
is needed to access GOT. If linker determines the function is defined
locally, it converts indirect branch via the GOT slot to direct branch
with a nop prefix and converts load via the GOT slot to load immediate
or lea.
* testsuite/ld-i386/libno-plt-1b.dd: New file.
* testsuite/ld-i386/libno-plt-1b.rd: Likewise.
* testsuite/ld-i386/no-plt-1a.dd: Likewise.
* testsuite/ld-i386/no-plt-1a.rd: Likewise.
* testsuite/ld-i386/no-plt-1b.dd: Likewise.
* testsuite/ld-i386/no-plt-1b.rd: Likewise.
* testsuite/ld-i386/no-plt-1c.dd: Likewise.
* testsuite/ld-i386/no-plt-1c.rd: Likewise.
* testsuite/ld-i386/no-plt-1d.dd: Likewise.
* testsuite/ld-i386/no-plt-1d.rd: Likewise.
* testsuite/ld-i386/no-plt-1e.dd: Likewise.
* testsuite/ld-i386/no-plt-1e.rd: Likewise.
* testsuite/ld-i386/no-plt-1f.dd: Likewise.
* testsuite/ld-i386/no-plt-1f.rd: Likewise.
* testsuite/ld-i386/no-plt-1g.dd: Likewise.
* testsuite/ld-i386/no-plt-1g.rd: Likewise.
* testsuite/ld-i386/no-plt-1h.dd: Likewise.
* testsuite/ld-i386/no-plt-1h.rd: Likewise.
* testsuite/ld-i386/no-plt-1i.dd: Likewise.
* testsuite/ld-i386/no-plt-1i.rd: Likewise.
* testsuite/ld-i386/no-plt-1j.dd: Likewise.
* testsuite/ld-i386/no-plt-1j.rd: Likewise.
* testsuite/ld-i386/no-plt-check1a.S: Likewise.
* testsuite/ld-i386/no-plt-check1b.S: Likewise.
* testsuite/ld-i386/no-plt-extern1a.S: Likewise.
* testsuite/ld-i386/no-plt-extern1b.S: Likewise.
* testsuite/ld-i386/no-plt-func1.c: Likewise.
* testsuite/ld-i386/no-plt-main1.c: Likewise.
* testsuite/ld-i386/no-plt.exp: Likewise.
We can generate i386 TLS code sequences for general and local dynamic
models without PLT, which uses indirect call via GOT:
call *___tls_get_addr@GOT(%reg)
where EBX register isn't required as GOT base, instead of direct call:
call ___tls_get_addr[@PLT]
which requires EBX register as GOT base.
Since direct call is 4-byte long and indirect call, is 5-byte long, the
extra one byte must be handled properly.
For general dynamic model, 7-byte lea instruction before call instruction
is replaced by 6-byte one to make room for indirect call. For local
dynamic model, we simply use 5-byte indirect call.
TLS linker optimization is updated to recognize new instruction patterns.
For local dynamic model to local exec model transition, we generate
a 6-byte lea instruction as nop, instead of a 1-byte nop plus a 4-byte
lea instruction. Since linker may convert
call ___tls_get_addr[@PLT]
to
addr32 call ____tls_get_addr
when producing static executable, both patterns are recognized.
bfd/
* elf64-i386.c (elf_i386_link_hash_entry): Add tls_get_addr.
(elf_i386_link_hash_newfunc): Initialize tls_get_addr to 2.
(elf_i386_check_tls_transition): Check indirect call and direct
call with the addr32 prefix for general and local dynamic models.
Set the tls_get_addr feild.
(elf_i386_convert_load_reloc): Always use addr32 prefix for
indirect ___tls_get_addr call via GOT.
(elf_i386_relocate_section): Handle GD->LE, GD->IE and LD->LE
transitions with indirect call and direct call with the addr32
prefix.
ld/
* testsuite/ld-i386/i386.exp: Run libtlspic2.so, tlsbin2,
tlsgd3, tlsld2, tlsgd4, tlspie3a, tlspie3b and tlspie3c.
* testsuite/ld-i386/pass.out: New file.
* testsuite/ld-i386/tls-def1.c: Likewise.
* testsuite/ld-i386/tls-gd1.S: Likewise.
* testsuite/ld-i386/tls-ld1.S: Likewise.
* testsuite/ld-i386/tls-main1.c: Likewise.
* testsuite/ld-i386/tls.exp: Likewise.
* testsuite/ld-i386/tlsbin2-nacl.rd: Likewise.
* testsuite/ld-i386/tlsbin2.dd: Likewise.
* testsuite/ld-i386/tlsbin2.rd: Likewise.
* testsuite/ld-i386/tlsbin2.sd: Likewise.
* testsuite/ld-i386/tlsbin2.td: Likewise.
* testsuite/ld-i386/tlsbinpic2.s: Likewise.
* testsuite/ld-i386/tlsgd3.dd: Likewise.
* testsuite/ld-i386/tlsgd3.s: Likewise.
* testsuite/ld-i386/tlsgd4.d: Likewise.
* testsuite/ld-i386/tlsgd4.s: Likewise.
* testsuite/ld-i386/tlsld2.s: Likewise.
* testsuite/ld-i386/tlspic2-nacl.rd: Likewise.
* testsuite/ld-i386/tlspic2.dd: Likewise.
* testsuite/ld-i386/tlspic2.rd: Likewise.
* testsuite/ld-i386/tlspic2.sd: Likewise.
* testsuite/ld-i386/tlspic2.td: Likewise.
* testsuite/ld-i386/tlspic3.s: Likewise.
* testsuite/ld-i386/tlspie3.s: Likewise.
* testsuite/ld-i386/tlspie3a.d: Likewise.
* testsuite/ld-i386/tlspie3b.d: Likewise.
* testsuite/ld-i386/tlspie3c.d: Likewise.
Don't convert R_386_GOT32 since we can't tell if it is applied
to "mov $foo@GOT, %reg" which isn't a load via GOT.
bfd/
PR ld/20117
* elf32-i386.c (elf_i386_convert_load_reloc): Don't check
R_386_GOT32X.
(elf_i386_convert_load): Don't convert R_386_GOT32.
ld/
PR ld/20117
* testsuite/ld-i386/i386.exp: Run pr20117.
* testsuite/ld-i386/pr19609-1i.d: Updated.
* testsuite/ld-i386/pr20117.d: New file.
* testsuite/ld-i386/pr20117.s: Likewise.
We shouldn't issue an error for read-only segment with dynamic IFUNC
relocations when dynamic relocations are against normal symbols.
bfd/
PR ld/19939
* elf-bfd.h (_bfd_elf_allocate_ifunc_dyn_relocs): Add a pointer
to bfd_boolean.
* elf-ifunc.c (_bfd_elf_allocate_ifunc_dyn_relocs): Updated.
Set *readonly_dynrelocs_against_ifunc_p to TRUE if dynamic reloc
applies to read-only section.
* elf32-i386.c (elf_i386_link_hash_table): Add
readonly_dynrelocs_against_ifunc.
(elf_i386_allocate_dynrelocs): Updated.
(elf_i386_size_dynamic_sections): Issue an error for read-only
segment with dynamic IFUNC relocations only if
readonly_dynrelocs_against_ifunc is TRUE.
* elf64-x86-64.c (elf_x86_64_link_hash_table): Add
readonly_dynrelocs_against_ifunc.
(elf_x86_64_allocate_dynrelocs): Updated.
(elf_x86_64_size_dynamic_sections): Issue an error for read-only
segment with dynamic IFUNC relocations only if
readonly_dynrelocs_against_ifunc is TRUE.
* elfnn-aarch64.c (elfNN_aarch64_allocate_ifunc_dynrelocs):
Updated.
ld/
PR ld/19939
* testsuite/ld-i386/i386.exp: Run PR ld/19939 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr19939.s: New file.
* testsuite/ld-i386/pr19939a.d: Likewise.
* testsuite/ld-i386/pr19939b.d: Likewise.
* testsuite/ld-x86-64/pr19939.s: Likewise.
* testsuite/ld-x86-64/pr19939a.d: Likewise.
* testsuite/ld-x86-64/pr19939b.d: Likewise.
Symbols defined in PIE should be bound locally, the same as -shared
-Bsymbolic.
bfd/
PR ld/19827
* elf32-i386.c (elf_i386_check_relocs): Bind defined symbol
locally in PIE.
(elf_i386_relocate_section): Likewise.
* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
(elf_x86_64_relocate_section): Likewise.
ld/
PR ld/19827
* testsuite/ld-i386/i386.exp: Run PR ld/19827 tests.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
* testsuite/ld-i386/pr19827.rd: New file.
* testsuite/ld-i386/pr19827a.S: Likewise.
* testsuite/ld-i386/pr19827b.S: Likewise.
* testsuite/ld-x86-64/pr19827.rd: Likewise.
* testsuite/ld-x86-64/pr19827a.S: Likewise.
* testsuite/ld-x86-64/pr19827b.S: Likewise.
Increment PLT reference count for locally defined local IFUNC symbols
in shared object since STT_GNU_IFUNC symbol must go through PLT even
if it is locally defined and undefined symbol may turn out to be a
STT_GNU_IFUNC symbol later.
bfd/
PR ld/19784
* elf32-i386.c (elf_i386_check_relocs): Increment PLT reference
count for locally defined local IFUNC symbols in shared object.
* elf64-x86-64.c (elf_x86_64_check_relocs): Likewise.
ld/
PR ld/19784
* testsuite/ld-i386/i386.exp: Remove pr19636-2e-nacl test.
* testsuite/ld-i386/pr19636-2e-nacl.d: Moved to ...
* testsuite/ld-i386/pr19636-2e.d: Here. Remove notarget.
* testsuite/ld-ifunc/ifunc.exp: Run PR ld/19784 tests.
* testsuite/ld-ifunc/pass.out: New file.
* testsuite/ld-ifunc/pr19784a.c: Likewise.
* testsuite/ld-ifunc/pr19784b.c: Likewise.
* testsuite/ld-ifunc/pr19784c.c: Likewise.
Since compiler may pass --as-needed to ld by default, link .o file
before .so file in i386/x86-64 tests.
PR ld/19774
* testsuite/ld-i386/i386.exp: Link tmpdir/pr18900.o before
tmpdir/pr18900.so and test --as-needed. Link tmpdir/gotpc1.o
before tmpdir/got1d.so and test --as-needed.
* testsuite/ld-x86-64/x86-64.exp: Link tmpdir/pr18900.o before
tmpdir/pr18900.so and test --as-needed.
Since compiler may pass --as-needed to ld by default, link
tmpdir/copyreloc-main.o before tmpdir/copyreloc-lib.so.
* testsuite/ld-i386/i386.exp: Link tmpdir/copyreloc-main.o
before tmpdir/copyreloc-lib.so and test --as-needed.
* testsuite/ld-x86-64/x86-64.exp: Likewise.
R_386_GOT32X, R_X86_64_GOTPCRELX and R_X86_64_REX_GOTPCRELX relocations
retrieve the symbol address via its GOT slot. If the symbol address is
known at the link-time, we can use it directly by changing instruction
encoding. Indirect branch can only be converted to PC relative direct
branch. MOV can be changed to LEA or encoded differently with signed
address. The subset of binary operations can be encoded only with
signed address.
If undefined weak symbol is resolved to zero link-time, we can use it
as address. Zero addresss can't used with PC relative direct branch
when PIC is true since the current PC is unknown. In 64-bit, 32-bit
relocation for PC relatiave direct branch to zero may also overflow.
If this optimization causes relocation overflow, --no-relax can be used
to work around it.
bfd/
PR ld/19609
* elf32-i386.c (elf_i386_convert_load): Convert to R_386_32 for
load with locally bound symbols if PIC is false or there is no
base register. Optimize branch to 0 if PIC is false.
(elf_i386_relocate_section): Don't generate dynamic relocations
against undefined weak symbols if PIC is false.
* elf64-x86-64.c (elf_x86_64_convert_load): Disable optimization
if we can't estimate relocation overflow with --no-relax.
Convert to R_X86_64_32S/R_X86_64_32 for load with locally bound
symbols if PIC is false. Optimize branch to 0 if PIC is false.
(elf_x86_64_relocate_section): Don't generate dynamic relocations
against undefined weak symbols if PIC is false.
ld/
PR ld/19609
* testsuite/ld-i386/got1.dd: Updated.
* testsuite/ld-i386/lea1c.d: Likewise.
* testsuite/ld-i386/load1-nacl.d: Likewise.
* testsuite/ld-i386/load1.d: Likewise.
* testsuite/ld-i386/load4b.d: Likewise.
* testsuite/ld-i386/load5b.d: Likewise.
* testsuite/ld-i386/mov1b.d: Likewise.
* testsuite/ld-x86-64/mov1b.d: Likewise.
* testsuite/ld-x86-64/mov1d.d: Likewise.
* testsuite/ld-ifunc/ifunc-21-i386.d: Likewise.
* testsuite/ld-ifunc/ifunc-21-x86-64.d: Likewise.
* testsuite/ld-ifunc/ifunc-22-i386.d: Likewise.
* testsuite/ld-ifunc/ifunc-22-x86-64.d: Likewise.
* testsuite/ld-x86-64/gotpcrel1.dd: Likewise.
* testsuite/ld-x86-64/lea1a.d: Likewise.
* testsuite/ld-x86-64/lea1b.d: Likewise.
* testsuite/ld-x86-64/lea1c.d: Likewise.
* testsuite/ld-x86-64/lea1d.d: Likewise.
* testsuite/ld-x86-64/lea1e.d: Likewise.
* testsuite/ld-x86-64/lea1f.d: Likewise.
* testsuite/ld-x86-64/mov1b.d: Likewise.
* testsuite/ld-x86-64/mov1d.d: Likewise.
* testsuite/ld-x86-64/pr13082-3b.d: Likewise.
* testsuite/ld-x86-64/pr13082-4b.d: Likewise.
* testsuite/ld-x86-64/lea1.s: Add tests for 32-bit registers.
* testsuite/ld-i386/pr19609-1.s: New file.
* testsuite/ld-i386/pr19609-1a.d: Likewise.
* testsuite/ld-i386/pr19609-1b.d: Likewise.
* testsuite/ld-i386/pr19609-1c.d: Likewise.
* testsuite/ld-i386/pr19609-1d.d: Likewise.
* testsuite/ld-i386/pr19609-1e.d: Likewise.
* testsuite/ld-i386/pr19609-1f.d: Likewise.
* testsuite/ld-i386/pr19609-1g.d: Likewise.
* testsuite/ld-i386/pr19609-1h.d: Likewise.
* testsuite/ld-i386/pr19609-1i.d: Likewise.
* testsuite/ld-i386/pr19609-2.s: Likewise.
* testsuite/ld-i386/pr19609-2a.d: Likewise.
* testsuite/ld-i386/pr19609-2b.d: Likewise.
* testsuite/ld-i386/pr19609-2c.d: Likewise.
* testsuite/ld-i386/undefweak.s: Likewise.
* testsuite/ld-i386/undefweaka.d: Likewise.
* testsuite/ld-i386/undefweakb.d: Likewise.
* testsuite/ld-x86-64/pr13082-3c.d: Likewise.
* testsuite/ld-x86-64/pr13082-3d.d: Likewise.
* testsuite/ld-x86-64/pr19609-1.s: Likewise.
* testsuite/ld-x86-64/pr19609-1a.d: Likewise.
* testsuite/ld-x86-64/pr19609-1b.d: Likewise.
* testsuite/ld-x86-64/pr19609-1c.d: Likewise.
* testsuite/ld-x86-64/pr19609-1d.d: Likewise.
* testsuite/ld-x86-64/pr19609-1e.d: Likewise.
* testsuite/ld-x86-64/pr19609-1f.d: Likewise.
* testsuite/ld-x86-64/pr19609-1g.d: Likewise.
* testsuite/ld-x86-64/pr19609-1h.d: Likewise.
* testsuite/ld-x86-64/pr19609-1i.d: Likewise.
* testsuite/ld-x86-64/pr19609-1j.d: Likewise.
* testsuite/ld-x86-64/pr19609-1k.d: Likewise.
* testsuite/ld-x86-64/pr19609-1l.d: Likewise.
* testsuite/ld-x86-64/pr19609-1m.d: Likewise.
* testsuite/ld-x86-64/pr19609-2.s: Likewise.
* testsuite/ld-x86-64/pr19609-2a.d: Likewise.
* testsuite/ld-x86-64/pr19609-2b.d: Likewise.
* testsuite/ld-x86-64/pr19609-2c.d: Likewise.
* testsuite/ld-x86-64/pr19609-2d.d: Likewise.
* testsuite/ld-x86-64/pr19609-3.s: Likewise.
* testsuite/ld-x86-64/pr19609-3a.d: Likewise.
* testsuite/ld-x86-64/pr19609-3b.d: Likewise.
* testsuite/ld-x86-64/pr19609-4.s: Likewise.
* testsuite/ld-x86-64/pr19609-4a.d: Likewise.
* testsuite/ld-x86-64/pr19609-4b.d: Likewise.
* testsuite/ld-x86-64/pr19609-4c.d: Likewise.
* testsuite/ld-x86-64/pr19609-4d.d: Likewise.
* testsuite/ld-x86-64/pr19609-4e.d: Likewise.
* testsuite/ld-x86-64/pr19609-5.s: Likewise.
* testsuite/ld-x86-64/pr19609-5a.d: Likewise.
* testsuite/ld-x86-64/pr19609-5b.d: Likewise.
* testsuite/ld-x86-64/pr19609-5c.d: Likewise.
* testsuite/ld-x86-64/pr19609-5d.d: Likewise.
* testsuite/ld-x86-64/pr19609-5e.d: Likewise.
* testsuite/ld-x86-64/pr19609-6.s: Likewise.
* testsuite/ld-x86-64/pr19609-6a.d: Likewise.
* testsuite/ld-x86-64/pr19609-6b.d: Likewise.
* testsuite/ld-x86-64/pr19609-6c.d: Likewise.
* testsuite/ld-x86-64/pr19609-6d.d: Likewise.
* testsuite/ld-x86-64/pr19609-7.s: Likewise.
* testsuite/ld-x86-64/pr19609-7a.d: Likewise.
* testsuite/ld-x86-64/pr19609-7b.d: Likewise.
* testsuite/ld-x86-64/pr19609-7c.d: Likewise.
* testsuite/ld-x86-64/pr19609-7d.d: Likewise.
* testsuite/ld-i386/i386.exp: Run undefweak tests and tests for
PR ld/19609.
* testsuite/ld-x86-64/x86-64.exp: Run pr13082-3c, pr13082-3d
and tests for PR ld/19609.
H.J. Lu