caa65211bb
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.
13 lines
220 B
D
13 lines
220 B
D
#source: call1.s
|
|
#as: --64
|
|
#ld: -melf_x86_64 -z call-nop=prefix-addr
|
|
#objdump: -dw
|
|
|
|
.*: +file format .*
|
|
|
|
|
|
Disassembly of section .text:
|
|
|
|
#...
|
|
[ ]*[a-f0-9]+: 67 e8 ([0-9a-f]{2} ){4} * addr32 callq +[a-f0-9]+ <foo>
|
|
#pass
|