This patch adds -mshared option to x86 ELF assembler. By default,
assembler will optimize out non-PLT relocations against defined non-weak
global branch targets with default visibility. The -mshared option tells
the assembler to generate code which may go into a shared library
where all non-weak global branch targets with default visibility can
be preempted. The resulting code is slightly bigger. This option
only affects the handling of branch instructions.
This Linux kernel patch is needed to create a working x86 Linux kernel if
it hasn't been applied:
diff --git a/arch/x86/kernel/head_64.S b/arch/x86/kernel/head_64.S
index ae6588b..b91a00c 100644
--- a/arch/x86/kernel/head_64.S
+++ b/arch/x86/kernel/head_64.S
@@ -339,8 +339,8 @@ early_idt_handlers:
i = i + 1
.endr
-/* This is global to keep gas from relaxing the jumps */
-ENTRY(early_idt_handler)
+/* This is weak to keep gas from relaxing the jumps */
+WEAK(early_idt_handler)
cld
cmpl $2,(%rsp) # X86_TRAP_NMI
--
gas/
* config/tc-i386.c (shared): New.
(OPTION_MSHARED): Likewise.
(elf_symbol_resolved_in_segment_p): Add relocation argument.
Check PLT relocations and shared.
(md_estimate_size_before_relax): Pass fragP->fr_var to
elf_symbol_resolved_in_segment_p.
(md_longopts): Add -mshared.
(md_show_usage): Likewise.
(md_parse_option): Handle OPTION_MSHARED.
* doc/c-i386.texi: Document -mshared.
gas/testsuite/
* gas/i386/i386.exp: Don't run pcrel for ELF targets. Run
pcrel-elf, relax-4 and x86-64-relax-3 for ELF targets.
* gas/i386/pcrel-elf.d: New file.
* gas/i386/relax-4.d: Likewise.
* gas/i386/x86-64-relax-3.d: Likewise.
* gas/i386/relax-3.d: Pass -mshared to assembler. Updated.
* gas/i386/x86-64-relax-2.d: Likewise.
* gas/i386/relax-3.s: Add test for PLT relocation.
Remove the wait instructions for server processors, since they were never
implemented. Also add the extra operands added to the tlbie and slbia
instructions with ISA 2.06 and ISA 2.05 respectively.
binutils/
* MAINTAINERS: Add myself as PPC maintainer.
opcodes/
* ppc-opc.c (IH) New define.
(powerpc_opcodes) <wait>: Do not enable for POWER7.
<tlbie>: Add RS operand for POWER7.
<slbia>: Add IH operand for POWER6.
gas/testsuite/
* gas/ppc/power4.d: Add a slbia test.
* gas/ppc/power4.s: Likewise.
* gas/ppc/power6.d: Add slbia and tlbie tests.
* gas/ppc/power6.s: Likewise.
* gas/ppc/power7.d: Remove wait tests. Add a tlbie test.
* gas/ppc/power7.s: Likewise.
In a SHF_COMPRESSED compressed section, the raw compressed data should
begin immediately after the compression header. This patch removes the
extra zlib header from the SHF_COMPRESSED section.
bfd/
* bfd.c (bfd_update_compression_header): Also write the zlib
header if the SHF_COMPRESSED bit cleared..
(bfd_check_compression_header): Return the uncompressed size.
* compress.c (decompress_contents): Don't skip the zlib header.
(bfd_compress_section_contents): Properly handle ELFCOMPRESS_ZLIB,
which doesn't have the zlib header.
(bfd_init_section_decompress_status): Likewise.
(bfd_get_full_section_contents): Updated.
(bfd_is_section_compressed): Likewise.
(bfd_is_section_compressed_with_header): Return the uncompressed
size.
* elf.c (_bfd_elf_make_section_from_shdr): Updated.
* bfd-in2.h: Regenerated.
binutils/
* readelf.c (uncompress_section_contents): Add a parameter for
uncompressed size. Don't check the zlib header.
(load_specific_debug_section): Updated.
binutils/testsuite/
* binutils-all/compress.exp: Replace "$OBJDUMP -s -j .debug_info"
with "$OBJDUMP -W".
* binutils-all/libdw2-compressedgabi.out: Updated.
gas/
2015-05-14 H.J. Lu <hongjiu.lu@intel.com>
* write.c (compress_debug): Don't write the zlib header, which
is handled by bfd_update_compression_header.
Extra condition 'abs (addr - trampaddr) < J_RANGE / 2' for trampoline
selection results in regressions: when relaxable jump is little longer
than J_RANGE so that single trampoline makes two new jumps, one longer
than J_RANGE / 2 and one shorter, correct trampoline cannot be found.
Drop that condition.
2015-05-13 Max Filippov <jcmvbkbc@gmail.com>
gas/
* config/tc-xtensa.c (xtensa_relax_frag): Allow trampoline to be
closer than J_RANGE / 2 to jump frag.
gas/testsuite/
* gas/xtensa/trampoline.s: Add regression testcase.
This patch sets the default ELF output format of assembler and linker to
EM_IAMCU when binutils is configured to i?86-*-elfiamcu target.
gas/
* configure.tgt (arch): Set to iamcu for i386-*-elfiamcu target.
* config/tc-i386.c (i386_mach): Support iamcu.
(i386_target_format): Likewise.
ld/
* configure.tgt: Support i[3-7]86-*-elfiamcu target.
ld/testsuite/
* ld-i386/i386.exp (iamcu_tests): Run iamcu-4.
* ld-i386/iamcu-4.d: New file.
PR gas/18347
* config/tc-arm.h (TC_EQUAL_IN_INSN): Define.
* config/tc-arm.c (arm_tc_equal_in_insn): New function. Move
the symbol name checking code to here from...
(md_undefined_symbo): ... here.
On ELF target, the assembler normally generates code which can go into a
shared library where non-weak symbols can be preempted. The -mno-shared
option tells the assembler to generate code not for a shared library,
where non-weak symbols won't be preempted. The resulting code is slightly
smaller. This option mainly affects the handling of branch instructions.
gas/
* config/tc-i386.c (no_shared): New.
(OPTION_MNO_SHARED): Likewise.
(elf_symbol_resolved_in_segment_p): Check no_shared.
(md_longopts): Add mno-shared.
(md_parse_option): Handle OPTION_MNO_SHARED.
(md_show_usage): Add -mno-shared.
* doc/c-i386.texi: Document -mno-shared.
gas/testsuite/
* gas/i386/i386.exp: Run relax-4 and x86-64-relax-3.
* gas/i386/relax-4.d: New file.
* gas/i386/x86-64-relax-3.d: Likewise.
Branches to global non-weak symbols defined in the same segment with
non-default visibility can be optimized the same way as branches to
local symbols.
gas/
* config/tc-i386.c (elf_symbol_resolved_in_segment_p): New.
(md_estimate_size_before_relax): Use it.
gas/testsuite/
* gas/i386/i386.exp: Run relax-3 and x86-64-relax-2.
* gas/i386/relax-3.d: New file.
* gas/i386/relax-3.s: Likewise.
* gas/i386/x86-64-relax-2.d: Likewise.
gas/ChangeLog:
2015-05-06 Jose E. Marchesi <jose.marchesi@oracle.com>
* config/tc-sparc.c (sparc_ip): Support the %ncc "natural"
condition codes
* doc/c-sparc.texi (Sparc-Regs): Document %ncc.
gas/testsuite/ChangeLog:
2015-05-06 Jose E. Marchesi <jose.marchesi@oracle.com>
* gas/sparc/natural.s: New file.
* gas/sparc/natural-32.s: Likewise.
* gas/sparc/natural.d: Likewise.
* gas/sparc/natural-32.d: Likewise.
* gas/sparc/sparc.exp (sparc_elf_setup): Run the tests natural and
natural-32.
gas * config/tc-msp430.c (MAX_OP_LEN): Increase to 4096.
(msp430_make_init_symbols): New function.
(msp430_section): Call it.
(msp430_frob_section): Likewise.
ld * emulparams/msp430elf.sh (TEMPLATE_NAME): Change to msp430.
* scripttempl/msp430.sc (.text): Add .lower.text and .either.text.
(.data): Add .lower.data and .either.data.
(.bss): Add .lower.bss and .either.bss.
(.rodata): Add .lower.rodata and .either.rodata.
* emultempl/msp430.em: New file. Implements a new orphan
placement algorithm that divides sections between lower and upper
memory regions.
* Makefile.am (emsp430elf.c): Depend upon msp430.em.
*emsp430X.c): Likewise.
* Makefine.in: Regenerate.
Currently every fixup in the current segment is checked when relaxing
trampoline frag. This is very expensive. Make a searchable array of
fixups pointing at potentially oversized jumps at the beginning of every
relaxation pass and only check subset of this cache in the reach of
single jump from the trampoline frag currently being relaxed.
Original profile:
% time self children called name
-----------------------------------------
370.16 593.38 12283048/12283048 relax_segment
98.4 370.16 593.38 12283048 xtensa_relax_frag
58.91 269.26 2691463834/2699602236 xtensa_insnbuf_from_chars
68.35 68.17 811266668/813338977 S_GET_VALUE
36.85 29.51 2684369246/2685538060 xtensa_opcode_decode
28.34 8.84 2684369246/2685538060 xtensa_format_get_slot
12.39 5.94 2691463834/2699775044 xtensa_format_decode
0.03 4.60 4101109/4101109 relax_frag_for_align
0.18 1.76 994617/994617 relax_frag_immed
0.07 0.09 24556277/24851220 new_logical_line
0.06 0.00 12283048/14067410 as_where
0.04 0.00 7094588/15460506 xtensa_format_num_slots
0.00 0.00 1/712477 xtensa_insnbuf_alloc
-----------------------------------------
Same data, after optimization:
% time self children called name
-----------------------------------------
0.51 7.47 12283048/12283048 relax_segment
58.0 0.51 7.47 12283048 xtensa_relax_frag
0.02 4.08 4101109/4101109 relax_frag_for_align
0.18 1.39 994617/994617 relax_frag_immed
0.01 0.98 555/555 xtensa_cache_relaxable_fixups
0.21 0.25 7094588/16693271 xtensa_insnbuf_from_chars
0.06 0.12 24556277/24851220 new_logical_line
0.06 0.00 7094588/15460506 xtensa_format_num_slots
0.02 0.04 7094588/16866079 xtensa_format_decode
0.05 0.00 12283048/14067410 as_where
0.00 0.00 1/712477 xtensa_insnbuf_alloc
0.00 0.00 93808/93808 xtensa_find_first_cached_fixup
-----------------------------------------
2015-05-02 Max Filippov <jcmvbkbc@gmail.com>
gas/
* config/tc-xtensa.c (cached_fixupS, fixup_cacheS): New typedefs.
(struct cached_fixup, struct fixup_cache): New structures.
(fixup_order, xtensa_make_cached_fixup),
(xtensa_realloc_fixup_cache, xtensa_cache_relaxable_fixups),
(xtensa_find_first_cached_fixup, xtensa_delete_cached_fixup),
(xtensa_add_cached_fixup): New functions.
(xtensa_relax_frag): Cache fixups pointing at potentially
oversized jumps at the beginning of every relaxation pass. Only
check subset of this cache in the reach of single jump from the
trampoline frag currently being relaxed.
This x86 assembler patch:
https://sourceware.org/ml/binutils/2001-11/msg00344.html
generates a .note section for .arch directive so that GDB can tell which
architecture an i386 binary belongs:
https://sourceware.org/ml/binutils/2001-11/msg00271.html
However, x86 assembly code can have any instructions. A .note section
doesn't help. This patch removes it.
gas/
* config/tc-i386.c (i386_elf_emit_arch_note): Removed.
* config/tc-i386.h (md_end): Likewise.
(i386_elf_emit_arch_note): Likewise.
gas/testsuite/
* gas/i386/i386.exp: Run note.
* gas/i386/note.d: New file.
* gas/i386/note.s: Likewise.
PR gas/18347
gas * config/tc-arm.c (md_undefined_symbol): Issue a warning message
(if enabled) when the user creates a symbol with the same name as
an ARM instruction.
(flag_warn_syms): New static variable.
(arm_opts): Add mwarn-syms and mno-warn-syms.
* doc/c-arm.texi (ARM Options): Document the -m[no-]warn-syms
options.
tests * gas/arm/pr18347.s: New file: Test case.
* gas/arm/pr18347.l: New file: Expected assembler output.
* gas/arm/pr18347.d: New file: Test driver.
gas PR 18256
* config/tc-arm.c (encode_arm_cp_address): Issue an error message
if the operand is neither a register nor a vector.
tests * gas/arm/pr18256.s: New file: Test case.
* gas/arm/pr18256.l: New file: Expected assembler output.
* gas/arm/pr18256.d: New file: Test driver.
* ppc-opc.c (DCBT_EO): New define.
(powerpc_opcodes) <lbarx>: Enable for POWER8 and later.
<lharx>: Likewise.
<stbcx.>: Likewise.
<sthcx.>: Likewise.
<waitrsv>: Do not enable for POWER7 and later.
<waitimpl>: Likewise.
<dcbt>: Default to the two operand form of the instruction for all
"old" cpus. For "new" cpus, use the operand ordering that matches
whether the cpu is server or embedded.
<dcbtst>: Likewise.
gas/testsuite/
* gas/ppc/a2.s: Fixup test case due to dcbt/dcbtst embedded operand
ordering change.
* gas/ppc/a2.d: Likewise.
* gas/ppc/476.d: Likewise.
* gas/ppc/booke.s: Remove invalid 3 operand dcbt tests.
* gas/ppc/booke.d: Likewise.
* gas/ppc/power7.s: Remove lbarx, lharx, stbcx., sthcx., waitrsv
and waitimpl tests.
* gas/ppc/power7.d: Likewise.
gas/
* config/tc-mips.c (macro): State the recommended way of creating
32-bit or 64-bit addresses.
gas/testsuite/
* gas/mips/dla-warn.l: New file.
* gas/mips/dla-warn.s: New file.
* gas/mips/la-warn.l: New file.
* gas/mips/la-warn.s: New file.
* gas/mips/mips.exp: Run new tests.
Certain conversion operations as well as vfpclassp{d,s} are ambiguous
when the input operand is in memory and no broadcast is being used.
While in Intel mode this gets resolved by printing suitable operand
size modifiers, AT&T mode need mnemonic suffixes to be added.
gas/testsuite/
2015-04-23 Jan Beulich <jbeulich@suse.com>
* gas/i386/avx512dq.d: Add 'z' suffix to vfpclassp{d,s} non-
register, non-broadcast cases.
* gas/i386/x86-64-avx512dq.d: Likewise.
* gas/i386/avx512dq_vl.d: Add 'x' and 'y' suffixes to
vcvt{,u}qq2ps and vfpclassp{d,s} non-register, non-broadcast
cases.
* gas/i386/x86-64-avx512dq_vl.d: Likewise.
* gas/i386/avx512f_vl.d: Add 'x' and 'y' suffixes to
vcvt{,t}pd2{,u}dq and vcvtpd2ps non-register, non-broadcast
cases.
* gas/i386/x86-64-avx512f_vl.d: Likewise.
opcodes/
2015-04-23 Jan Beulich <jbeulich@suse.com>
* i386-dis.c (putop): Extend "XY" handling to AVX512. Handle "XZ".
* i386-dis-evex.h.c (vcvtpd2ps, vcvtqq2ps, vcvttpd2udq,
vcvtpd2udq, vcvtuqq2ps, vcvttpd2dq, vcvtpd2dq): Add %XY.
(vfpclasspd, vfpclassps): Add %XZ.
Certain conversion operations as well as vfpclassp{d,s} are ambiguous
when the input operand is in memory. That ambiguity, however, doesn't
apply when using broadcasts (the destination operand size can be
induced from the broadcast specifier).
gas/
2015-04-23 Jan Beulich <jbeulich@suse.com>
* config/tc-i386.c (match_mem_size): Also allow no size
specification when broadcasting.
gas/testsuite/
2015-04-23 Jan Beulich <jbeulich@suse.com>
* gas/i386/avx512dq.s: Drop 'z' suffix from vfpclassp{d,s} in
some AT&T and all Intel cases.
* gas/i386/x86-64-avx512dq.s: Likewise.
* gas/i386/avx512dq_vl.s: Drop 'x' and 'y' suffixes from
vcvt{,u}qq2ps and vfpclassp{d,s} in some AT&T and all Intel
cases.
* gas/i386/x86-64-avx512dq_vl.s: Likewise.
* gas/i386/avx512f_vl.s: Drop 'x' and 'y' suffixes from
vcvt{,t}pd2{,u}dq and vcvtpd2ps in some AT&T and all Intel
cases.
* gas/i386/x86-64-avx512f_vl.s: Likewise.
This patch silences texinfo 5.1 warnings by using @subsection and
sorting entries in Machine Dependencies menu.
* doc/as.texinfo (Bundle directives): Shorten menu entry and
use @subsection.
(CFI directives): Use @subsection.
(SH-Dependent, SH64-Dependent): Moved after SCORE-Dependent.
* doc/c-i386.texi (i386-Mnemonics): Use @subsection.
This patch puts rdrand and rdseed in prefix_table so that invalid
prefixes for rdrand and rdseed are handled properly.
gas/testsuite/
PR binutils/17898
* gas/i386/prefix.s: Add rdrand/rdseed prefix tests.
* gas/i386/prefix.d: Updated.
opcodes/
PR binutils/17898
* i386-dis.c (PREFIX_0FC7_REG_6): Renamed to ...
(PREFIX_MOD_0_0FC7_REG_6): This.
(PREFIX_MOD_3_0FC7_REG_6): New.
(PREFIX_MOD_3_0FC7_REG_7): Likewise.
(prefix_table): Replace PREFIX_0FC7_REG_6 with
PREFIX_MOD_0_0FC7_REG_6. Add PREFIX_MOD_3_0FC7_REG_6 and
PREFIX_MOD_3_0FC7_REG_7.
(mod_table): Replace PREFIX_0FC7_REG_6 with
PREFIX_MOD_0_0FC7_REG_6. Use PREFIX_MOD_3_0FC7_REG_6 and
PREFIX_MOD_3_0FC7_REG_7.
2015-04-15 Renlin Li <renlin.li@arm.com>
opcodes/:
* arm-dis.c (thumb32_opcodes): Define 'D' format control code,
use it for ssat and ssat16.
(print_insn_thumb32): Add handle case for 'D' control code.
gas/testsuite/:
* gas/arm/arch7em.d: Adjust required ssat and ssat16 immediate field.
* gas/arm/thumb32.d: Likewise.
This patch adds --compress-debug-sections=[none|zlib|zlib-gnu|zlib-gabi]
to ld for ELF targets to support generating compressed DWARF debug
sections. We always generate .zdebug_* section since section names have
been finalized and they can't be changed easily when compression is
being performed.
bfd/
* bfd-in.h (compressed_debug_section_type): New.
* compress.c (bfd_compress_section_contents): Add an argument
for linker write compression and always generate .zdebug_*
section when linking.
(bfd_init_section_compress_status): Pass FALSE to
bfd_compress_section_contents.
(bfd_compress_section): New function.
* elf.c (elf_fake_sections): For linking, set SEC_ELF_COMPRESS
on DWARF debug sections if COMPRESS_DEBUG is set and rename
section if COMPRESS_DEBUG_GABI_ZLIB isn't set.
(assign_file_positions_for_non_load_sections): Set sh_offset
to -1 if SEC_ELF_COMPRESS is set.
(assign_file_positions_except_relocs): Likwise.
(_bfd_elf_assign_file_positions_for_relocs): Renamed to ...
(_bfd_elf_assign_file_positions_for_non_load): This. Change
return time to bfd_boolean. Compress the section if
SEC_ELF_COMPRESS is set.
(_bfd_elf_write_object_contents): Updated.
(_bfd_elf_set_section_contents): Write section contents to
the buffer if SEC_ELF_COMPRESS is set.
* merge.c: Include "elf-bfd.h".
(sec_merge_emit): Add arguments for contents and offset. Write
to contents with offset if contents isn't NULL.
(_bfd_write_merged_section): Write section contents to the
buffer if SEC_ELF_COMPRESS is set. Pass contents and
output_offset to sec_merge_emit.
* elflink.c (bfd_elf_final_link): Allocate the buffer for
output section contents if SEC_ELF_COMPRESS is set.
* section.c (SEC_ELF_COMPRESS): New.
* bfd-in2.h: Regenerated.
gas/
* as.h (compressed_debug_section_type): Removed.
include/
* bfdlink.h (bfd_link_info): Add compress_debug.
ld/
* ld.texinfo: Document --compress-debug-sections=.
* ldmain.c (main): Set BFD_COMPRESS on output_bfd if
COMPRESS_DEBUG is set. Set BFD_COMPRESS_GABI on output_bfd
for COMPRESS_DEBUG_GABI_ZLIB.
* lexsup.c (elf_static_list_options): Add
--compress-debug-sections=.
* emultempl/elf32.em (OPTION_COMPRESS_DEBUG): New.
(xtra_long): Add "compress-debug-sections".
(gld${EMULATION_NAME}_handle_option): Handle
OPTION_COMPRESS_DEBUG.
ld/testsuite/
* ld-elf/compress.exp (build_tests): Add tests for
--compress-debug-sections=.
(run_tests): Likewise.
Add additonal tests for --compress-debug-sections=.
* ld-elf/gabiend.rt: New file.
* ld-elf/gabinormal.rt: Likewise.
* ld-elf/gnubegin.rS: Likewise.
* ld-elf/gnunormal.rS: Likewise.
* ld-elf/zlibbegin.rS: Likewise.
* ld-elf/zlibnormal.rS: Likewise.
gas * config/tc-rl78.h (TC_LINKRELAX_FIXUP): Define.
(TC_FORCE_RELOCATION_SUB_SAME): Define.
(DWARF2_USE_FIXED_ADVANCE_PC): Define.
* gas/lns/lns.exp: Add RL78 to list of targets using
DW_LNS_fixed_advance_pc.
bfd * elf32-rl78.c (RL78_OP_REL): New macro.
(rl78_elf_howto_table): Use it for complex relocs.
(get_symbol_value): Handle the cases when the info or status
arguments are NULL.
(get_romstart): Cache the status returned by get_symbol_value.
(get_ramstart): Likewise.
(RL78_STACK_PUSH): Generate an error message if the stack
overflows.
(RL78_STACK_POP): Likewise for underflows.
(rl78_compute_complex_reloc): New function. Contains the basic
processing code for all RL78 complex relocs.
(rl78_special_reloc): New function. Provides special reloc
handling for complex relocs.
(rl78_elf_relocate_section): Use rl78_compute_complex_reloc.
(rl78_offset_for_reloc): Likewise.
binutils* readelf.c (target_specific_reloc_handling): Add code to handle
RL78 complex relocs.
PR binutils/18198
* ld.texinfo (--be8): Add a note about the interaction of this
option with the assembler's -EB option.
* doc/c-arm.texi (ARM Options): Add a note about the interaction of
the -EB option with the linker's --be8 option.
