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binutils-gdb/ld/testsuite/ld-ifunc/ifunc-16-i386-now.d

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i386: Improve PLT generation and synthetic PLT symbols 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.
2017-05-09 01:10:22 +08:00
#source: ifunc-16-x86.s
#ld: -z now -shared -m elf_i386
#as: --32
#readelf: -r --wide
#target: x86_64-*-* i?86-*-*
Relocation section '.rel.plt' at .*
[ ]+Offset[ ]+Info[ ]+Type[ ]+.*
x86: Generate PLT relocations for -z now This patch partially reverses: commit 25070364b0ce33eed46aa5d78ebebbec6accec7e 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 25070364b0ce33eed46aa5d78ebebbec6accec7e. * 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.
2017-05-11 22:42:30 +08:00
[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_386_JUMP_SLOT[ ]+0+[ ]+ifunc
i386: Improve PLT generation and synthetic PLT symbols 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.
2017-05-09 01:10:22 +08:00
[0-9a-f]+[ ]+[0-9a-f]+[ ]+R_386_IRELATIVE[ ]*
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