2 Commits

Author	SHA1	Message	Date
H.J. Lu	cd04836359	x86: Remove the unused _GLOBAL_OFFSET_TABLE_ ... Since _GLOBAL_OFFSET_TABLE_ may be referenced implicitly on x86, checking ref_regular_nonweak leaves the unused _GLOBAL_OFFSET_TABLE_ in output. This patch checks explicit GOT references instead. ld-i386/discarded1.s and ld-x86-64/discarded1.s are updated to avoid linker optimization which removes GOT references. bfd/ PR ld/22782 * elf32-i386.c (elf_i386_check_relocs): Set got_referenced if _GLOBAL_OFFSET_TABLE_ is referenced or GOT is needed to resolve undefined weak symbol to 0. * elf64-x86-64.c (elf_x86_64_check_relocs): Set got_referenced if _GLOBAL_OFFSET_TABLE_ is referenced. * elfxx-x86.c (_bfd_x86_elf_size_dynamic_sections): Check got_referenced instead of ref_regular_nonweak. Remove the unused _GLOBAL_OFFSET_TABLE_ from symbol table. * elfxx-x86.h (elf_x86_link_hash_table): Add got_referenced. ld/ PR ld/22782 * testsuite/ld-i386/discarded1.s: Replace mov with div. * testsuite/ld-x86-64/discarded1.s: Likewise. * testsuite/ld-i386/i386.exp: Run pr22782. * testsuite/ld-i386/load1-nacl.d: Updated for removing _GLOBAL_OFFSET_TABLE_ from output. * testsuite/ld-i386/load1.d: Likewise. * testsuite/ld-x86-64/load1a-nacl.d: Likewise. * testsuite/ld-x86-64/load1a.d: Likewise. * testsuite/ld-x86-64/load1b-nacl.d: Likewise. * testsuite/ld-x86-64/load1b.d: Likewise. * testsuite/ld-i386/pr22782.d: New file. * testsuite/ld-i386/pr22782.s: Likewise. * testsuite/ld-x86-64/pr22782.s: Likewise. * testsuite/ld-x86-64/pr22782a.d: Likewise. * testsuite/ld-x86-64/pr22782b.d: Likewise. * testsuite/ld-x86-64/x86-64.exp: Run pr22782a and pr22782b.	2018-02-05 08:38:16 -08:00
H.J. Lu	caa65211bb	Add "-z call-nop=PADDING" option to ld ... The ld linker can transform indirect call to a locally defined function, foo, via its GOT slot, to either "NOP call foo" or "call foo NOP" where NOP is a 1-byte NOP padding. This patch adds a "-z call-nop=PADDING" option to x86 ld to control 1-byte NOP padding for x86 call instruction. PADDING is one of prefix-addr, prefix-nop, suffix-nop, prefix-NUMBER or suffix-NUMBER. bfd/ * elf32-i386.c (elf_i386_convert_load): Use call_nop_byte and check call_nop_as_suffix for 1-byte NOP padding to pad call. * elf64-x86-64.c (elf_x86_64_convert_load): Likewise. include/ * bfdlink.h (bfd_link_info): Add call_nop_as_suffix and call_nop_byte. ld/ * ld/ld.texinfo: Document "-z call-nop=PADDING" option. * emulparams/call_nop.sh: New file. * emulparams/elf_i386_be.sh: Source ${srcdir}/emulparams/call_nop.sh. * emulparams/elf_i386_chaos.sh: Likewise. * emulparams/elf_i386_ldso.sh: Likewise. * emulparams/elf_i386_vxworks.sh: Likewise. * emulparams/elf_iamcu.sh: Likewise. * emulparams/elf_k1om.sh: Likewise. * emulparams/elf_l1om.sh: Likewise. * emulparams/elf_x86_64.sh: Likewise. * emultempl/elf32.em (gld${EMULATION_NAME}_before_parse): Set link_info.call_nop_byte if $CALL_NOP_BYTE isn't empty. ld/testsuite/ * ld-i386/call3.s: New file. * ld-i386/call3a.d: Likewise. * ld-i386/call3b.d: Likewise. * ld-i386/call3c.d: Likewise. * ld-i386/call3d.d: Likewise. * ld-i386/call3e.d: Likewise. * ld-i386/call3f.d: Likewise. * ld-i386/call3g.d: Likewise. * ld-i386/call3h.d: Likewise. * ld-i386/load1-nacl.d: Likewise. * ld-x86-64/call1.s: Likewise. * ld-x86-64/call1a.d: Likewise. * ld-x86-64/call1b.d: Likewise. * ld-x86-64/call1c.d: Likewise. * ld-x86-64/call1d.d: Likewise. * ld-x86-64/call1e.d: Likewise. * ld-x86-64/call1f.d: Likewise. * ld-x86-64/call1g.d: Likewise. * ld-x86-64/call1h.d: Likewise. * ld-x86-64/call1i.d: Likewise. * ld-x86-64/load1a-nacl.d: Likewise. * ld-x86-64/load1b-nacl.d: Likewise. * ld-x86-64/load1c-nacl.d: Likewise. * ld-x86-64/load1d-nacl.d: Likewise.	2015-10-22 04:56:39 -07:00