Add R_386_GOT32X support to gas and ld
authorH.J. Lu <hjl.tools@gmail.com>
Thu, 22 Oct 2015 11:46:51 +0000 (04:46 -0700)
committerH.J. Lu <hjl.tools@gmail.com>
Thu, 22 Oct 2015 11:47:07 +0000 (04:47 -0700)
commit02a866936de7e63ad4962ccba56c8cd05c231275
tree057157847f8f10880700c0fd6e006bee27034697
parent99ba51255402201c6e193d803ee1f1fc3f2de0e6
Add R_386_GOT32X support to gas and ld

This patch adds support for the R_386_GOT32X relocation proposed in

https://groups.google.com/forum/#!topic/ia32-abi/GbJJskkid4I

to gas and ld.  It updates gas to generate R_386_GOT32X relocation for
memory operand, foo@GOT[(%reg)].  We must encode "mov foo@GOT, %eax"
with the 0x8b opcode, instead of the 0xb8 opcode, so that it can be
transformed to "lea foo, %eax".  With the locally defined symbol, foo,
we convert

   mov foo@GOT[(%reg1)], %reg2
to
   lea foo[@GOTOFF(%reg1)], %reg2

and convert

   call/jmp *foo@GOT[(%reg)]
to

   nop call foo/jmp foo nop

When PIC is false, convert

   test %reg1, foo@GOT[(%reg2)]
to
   test $foo, %reg1

and convert

binop foo@GOT[(%reg1)], %reg2

to

binop $foo, %reg2

where binop is one of adc, add, and, cmp, or, sbb, sub, xor instructions.

bfd/

* elf32-i386.c: Include opcode/i386.h.
(elf_howto_table): Add R_386_GOT32X.
(R_386_ext2): Replace R_386_IRELATIVE with R_386_GOT32X.
(elf_i386_reloc_type_lookup): Handle BFD_RELOC_386_GOT32X.
(need_convert_mov_to_lea): Renamed to ...
(need_convert_load): This.
(elf_i386_check_relocs): Handle R_386_GOT32X.  Replace
need_convert_mov_to_lea with need_convert_load.
(elf_i386_gc_sweep_hook): Handle R_386_GOT32X.
(elf_i386_size_dynamic_sections): Likewise.
(elf_i386_relocate_section): Likewise.
(elf_i386_convert_mov_to_lea): Renamed to ...
(elf_i386_convert_load): This.  Replace need_convert_mov_to_lea
with need_convert_load.  Support R_386_GOT32X transformations.
* reloc.c (BFD_RELOC_386_GOT32X): New.
* bfd-in2.h: Regenerated.
* libbfd.h: Likewise.

gas/

* config/tc-i386.c (tc_i386_fix_adjustable): Handle
BFD_RELOC_386_GOT32X.
(tc_gen_reloc): Likewise.
(match_template): Force 0x8b encoding for "mov foo@GOT, %eax".
(output_disp): Check for "call/jmp *mem", "mov mem, %reg",
"test %reg, mem" and "binop mem, %reg" where binop is one of
adc, add, and, cmp, or, sbb, sub, xor instructions.  Set
fx_tcbit if the REX prefix is generated.  Set fx_tcbit2 if
BFD_RELOC_386_GOT32X should be generated.
(i386_validate_fix): Generate BFD_RELOC_386_GOT32X if fx_tcbit2
is set.

gas/testsuite/

* gas/i386/got.d: New file.
* gas/i386/got.s: Likewise.
* gas/i386/i386.exp: Run got.
* gas/i386/localpic.d: Replace R_386_GOT32 with R_386_GOT32X.
* gas/i386/mixed-mode-reloc32.d: Likewise.
* gas/i386/reloc32.d: Likewise.

include/elf/

* i386.h (R_386_GOT32X): New relocation.

ld/testsuite/

* ld-i386/branch1.d: New file.
* ld-i386/branch1.s: Likewise.
* ld-i386/call1.d: Likewise.
* ld-i386/call1.s: Likewise.
* ld-i386/call2.d: Likewise.
* ld-i386/call2.s: Likewise.
* ld-i386/got1.dd: Likewise.
* ld-i386/got1.out: Likewise.
* ld-i386/got1a.S: Likewise.
* ld-i386/got1b.c: Likewise.
* ld-i386/got1c.c: Likewise.
* ld-i386/got1d.S: Likewise.
* ld-i386/jmp1.d: Likewise.
* ld-i386/jmp1.s: Likewise.
* ld-i386/jmp2.d: Likewise.
* ld-i386/jmp2.s: Likewise.
* ld-i386/load1.d: Likewise.
* ld-i386/load1.s: Likewise.
* ld-i386/load2.d: Likewise.
* ld-i386/load2.s: Likewise.
* ld-i386/load3.d: Likewise.
* ld-i386/load3.s: Likewise.
* ld-i386/load4.s: Likewise.
* ld-i386/load4a.d: Likewise.
* ld-i386/load4b.d: Likewise.
* ld-i386/load5.s: Likewise.
* ld-i386/load5a.d: Likewise.
* ld-i386/load5b.d: Likewise.
* ld-i386/load6.d: Likewise.
* ld-i386/load6.s: Likewise.
* ld-i386/i386.exp: Run branch1, call1, call2, jmp1, jmp2,
load1, load2, load3, load4a, load4b, load5a, load5b and load6
tests.  Run got1 test.
52 files changed:
bfd/ChangeLog
bfd/bfd-in2.h
bfd/elf32-i386.c
bfd/libbfd.h
bfd/reloc.c
gas/ChangeLog
gas/config/tc-i386.c
gas/testsuite/ChangeLog
gas/testsuite/gas/i386/got.d [new file with mode: 0644]
gas/testsuite/gas/i386/got.s [new file with mode: 0644]
gas/testsuite/gas/i386/i386.exp
gas/testsuite/gas/i386/localpic.d
gas/testsuite/gas/i386/mixed-mode-reloc32.d
gas/testsuite/gas/i386/reloc32.d
include/elf/ChangeLog
include/elf/i386.h
ld/testsuite/ChangeLog
ld/testsuite/ld-i386/branch1.d [new file with mode: 0644]
ld/testsuite/ld-i386/branch1.s [new file with mode: 0644]
ld/testsuite/ld-i386/call1.d [new file with mode: 0644]
ld/testsuite/ld-i386/call1.s [new file with mode: 0644]
ld/testsuite/ld-i386/call2.d [new file with mode: 0644]
ld/testsuite/ld-i386/call2.s [new file with mode: 0644]
ld/testsuite/ld-i386/got1.dd [new file with mode: 0644]
ld/testsuite/ld-i386/got1.out [new file with mode: 0644]
ld/testsuite/ld-i386/got1a.S [new file with mode: 0644]
ld/testsuite/ld-i386/got1b.c [new file with mode: 0644]
ld/testsuite/ld-i386/got1c.c [new file with mode: 0644]
ld/testsuite/ld-i386/got1d.S [new file with mode: 0644]
ld/testsuite/ld-i386/i386.exp
ld/testsuite/ld-i386/jmp1.d [new file with mode: 0644]
ld/testsuite/ld-i386/jmp1.s [new file with mode: 0644]
ld/testsuite/ld-i386/jmp2.d [new file with mode: 0644]
ld/testsuite/ld-i386/jmp2.s [new file with mode: 0644]
ld/testsuite/ld-i386/lea1c.d
ld/testsuite/ld-i386/load1.d [new file with mode: 0644]
ld/testsuite/ld-i386/load1.s [new file with mode: 0644]
ld/testsuite/ld-i386/load2.d [new file with mode: 0644]
ld/testsuite/ld-i386/load2.s [new file with mode: 0644]
ld/testsuite/ld-i386/load3.d [new file with mode: 0644]
ld/testsuite/ld-i386/load3.s [new file with mode: 0644]
ld/testsuite/ld-i386/load4.s [new file with mode: 0644]
ld/testsuite/ld-i386/load4a.d [new file with mode: 0644]
ld/testsuite/ld-i386/load4b.d [new file with mode: 0644]
ld/testsuite/ld-i386/load5.s [new file with mode: 0644]
ld/testsuite/ld-i386/load5a.d [new file with mode: 0644]
ld/testsuite/ld-i386/load5b.d [new file with mode: 0644]
ld/testsuite/ld-i386/load6.d [new file with mode: 0644]
ld/testsuite/ld-i386/load6.s [new file with mode: 0644]
ld/testsuite/ld-i386/plt-main1.rd
ld/testsuite/ld-i386/plt-main3.rd
ld/testsuite/ld-i386/plt-main4.rd