Commit Graph

3 Commits

Author SHA1 Message Date
Jan Beulich
36938cabf0 x86: avoid attaching suffixes to unambiguous insns
"Unambiguous" is is in particular taking as reference the assembler,
which also accepts certain insns - despite them allowing for varying
operand size, and hence in principle being ambiguous - without any
suffix. For example, from the very beginning of the life of x86-64 I had
trouble understanding why a plain and simple RET had to be printed as
RETQ. In case someone really used the 16-bit form, RETW disambiguates
the two quite fine.
2020-07-15 08:53:55 +02:00
H.J. Lu
0cb4071ef9 Add -mrelax-relocations= to x86 assembler
The x86 relax relocations introduced in binutils 2.26 aren't supported
by linker on Solaris older than Solaris 12.  To use x86 assembler with
older Solaris linker, this patch adds

1. A command line option -mrelax-relocations= to x86 assembler to
control whether to generate relax relocations.
2. A configure option --enable-x86-relax-relocations to decide whether
x86 assembler should generate relax relocations by default.  It is
defaulted to yes, except for x86 Solaris targets older than Solaris 12.

gas/

	PR gas/19520
	* NEWS: Mention new command line option -mrelax-relocations and
	new configure option --enable-x86-relax-relocations for x86
	target.
	* config.in: Regenerated.
	* configure.ac: Add --enable-x86-relax-relocations.
	(ac_default_x86_relax_relocations): New.  Default to 1 except
	for x86 Solaris targets older than Solaris 12.
	(DEFAULT_GENERATE_X86_RELAX_RELOCATIONS): Define.
	* configure: Likewise.
	* config/tc-i386.c (generate_relax_relocations): New.
	(OPTION_MRELAX_RELOCATIONS): Likewise.
	(output_disp): Don't generate relax relocations if
	generate_relax_relocations is 0.
	(md_longopts): Add -mrelax-relocations.
	(md_show_usage): Likewise.
	(md_parse_option): Handle OPTION_MRELAX_RELOCATIONS.
	* doc/c-i386.texi: Document -mrelax-relocations=.
	* testsuite/gas/i386/got-no-relax.d: New file.
	* testsuite/gas/i386/x86-64-gotpcrel-no-relax.d: Likewise.
	* testsuite/gas/i386/got.d: Pass -mrelax-relocations=yes to as.
	* testsuite/gas/i386/localpic.d: Likewise.
	* testsuite/gas/i386/mixed-mode-reloc32.d: Likewise.
	* testsuite/gas/i386/reloc32.d: Likewise.
	* testsuite/gas/i386/x86-64-gotpcrel.d: Likewise.
	* testsuite/gas/i386/x86-64-localpic.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-gotpcrel.d: Likewise.
	* testsuite/gas/i386/ilp32/x86-64-localpic.d: Likewise.
	* testsuite/gas/i386/i386.exp: Run got-no-relax and
	x86-64-gotpcrel-no-relax.

ld/

	PR gas/19520
	* testsuite/ld-i386/branch1.d: Pass -mrelax-relocations=yes to as.
	* testsuite/ld-i386/call1.d: Likewise.
	* testsuite/ld-i386/call2.d: Likewise.
	* testsuite/ld-i386/call3a.d: Likewise.
	* testsuite/ld-i386/call3b.d: Likewise.
	* testsuite/ld-i386/call3c.d: Likewise.
	* testsuite/ld-i386/call3d.d: Likewise.
	* testsuite/ld-i386/call3e.d: Likewise.
	* testsuite/ld-i386/call3f.d: Likewise.
	* testsuite/ld-i386/call3g.d: Likewise.
	* testsuite/ld-i386/call3h.d: Likewise.
	* testsuite/ld-i386/jmp1.d: Likewise.
	* testsuite/ld-i386/jmp2.d: Likewise.
	* testsuite/ld-i386/lea1c.d: Likewise.
	* testsuite/ld-i386/load1.d: Likewise.
	* testsuite/ld-i386/load2.d: Likewise.
	* testsuite/ld-i386/load3.d: Likewise.
	* testsuite/ld-i386/load4a.d: Likewise.
	* testsuite/ld-i386/load5a.d: Likewise.
	* testsuite/ld-i386/mov2b.d: Likewise.
	* testsuite/ld-i386/mov3.d: Likewise.
	* testsuite/ld-ifunc/ifunc-21-x86-64.d: Likewise.
	* testsuite/ld-ifunc/ifunc-22-x86-64.d: Likewise.
	* testsuite/ld-ifunc/ifunc-5r-local-x86-64.d: Likewise.
	* testsuite/ld-x86-64/call1a.d: Likewise.
	* testsuite/ld-x86-64/call1b.d: Likewise.
	* testsuite/ld-x86-64/call1c.d: Likewise.
	* testsuite/ld-x86-64/call1d.d: Likewise.
	* testsuite/ld-x86-64/call1e.d: Likewise.
	* testsuite/ld-x86-64/call1f.d: Likewise.
	* testsuite/ld-x86-64/call1h.d: Likewise.
	* testsuite/ld-x86-64/call1i.d: Likewise.
	* testsuite/ld-x86-64/load1a.d: Likewise.
	* testsuite/ld-x86-64/load1b.d: Likewise.
	* testsuite/ld-i386/got1a.S: Load GOT into %ecx and use it.
	* testsuite/ld-i386/got1.dd: Updated.
	* testsuite/ld-i386/got1d.S (1): Removed.
	* testsuite/ld-i386/i386.exp: Add -Wa,-mrelax-relocations=yes.
	* testsuite/ld-x86-64/x86-64.exp: Likewise.
2016-02-03 08:25:15 -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