ELF-only functions don't need to be built when dealing with a non-ELF
target. md_section_align() also doesn't need to be a function when
dealing with non-AOUT targets. Similarly tc_fix_adjustable() can be a
simple macro when building non-ELF targets.
Furthermore x86_elf_abi is already used in ELF-only code sections, with
one exception. By adjusting that, the otherwise bogusly named variable
can also be confined to just ELF builds.
The two are distinct in opcodes/, distinguished precisely by CpuNOP
that's relevant in i386_generate_nops(), yet the function has the PPro
case label in the other group. Simply removing it revealed that
cpu_arch[] had a wrong entry for i686.
While there also add PROCESSOR_IAMCU to the respective comment.
Making GENERIC64 a special case was never correct; prior to the
generalization of ".arch .no*" to cover all ISA extensions other
processor families supporting long NOPs should have been covered as
well. When introducing ".arch .nonops" (among others) it wasn't
apparent that a hidden implication of .cpunop not being possible to
separately turn off existed here. Seeing that the two large case label
blocks in the 2nd switch() already had identical behavior, simply
collapse all of the (useful) case labels into a single "default" one.
The recorded value, and not the global variable, will want using in
TC_FRAG_INIT(). The so far file scope variable therefore needs to become
external, to be accessible there.
It's not documented anyway, and having it makes no sense anymore with
obj_elf_section_word() now being TC_SPARC-only. In any event the x86
backing function was dead code.
While a442cac508 ("ix86: wrap constants") helped address a number of
inconsistencies between BFD64 and !BFD64 builds, it has also resulted in
certain bogus uses of constants to no longer be warned about. Leverage
the md_optimize_expr() hook to adjust when to actually truncate
expressions to 32 bits - any involvement of binary expressions (which
would be evaluated in 32 bits only when !BFD64) signals the need for
doing so. Plain constants (or ones merely subject to unary operators)
should remain un-truncated - they would be handled as bignums when
!BFD64, and hence are okay to permit.
To compensate
- slightly extend optimize_imm() (to be honest I never understood why
the code being added - or something similar - wasn't there in the
first place),
- adjust expectations of the disp-imm-32 testcase (there are now
warnings, as there should be for any code which won't build [warning-
free] when !BFD64, and Disp8/Imm8 are no longer used in the warned
about cases).
The newer update-copyright.py fixes file encoding too, removing cr/lf
on binutils/bfdtest2.c and ld/testsuite/ld-cygwin/exe-export.exp, and
embedded cr in binutils/testsuite/binutils-all/ar.exp string match.
Currently supported for x86_64 and aarch64 only.
[PS: Currently, the compiler has not been adapted to generate
".cfi_sections" with ".sframe" in it. The newly added command line
option of --gsframe provides an easy way to try out .sframe support
in the toolchain.]
gas interprets the CFI directives to generate DWARF-based .eh_frame
info. These internal DWARF structures are now consumed by
gen-sframe.[ch] sub-system to, in turn, create the SFrame unwind
information. These internal DWARF structures are read-only for the
purpose of SFrame unwind info generation.
SFrame unwind info generation does not impact .eh_frame unwind info
generation. Both .eh_frame and .sframe can co-exist in an ELF file,
if so desired by the user.
Recall that SFrame unwind information only contains the minimal
necessary information to generate backtraces and does not provide
information to recover all callee-saved registers. The reason being
that callee-saved registers other than FP are not needed for stack
unwinding, and hence are not included in the .sframe section.
Consequently, gen-sframe.[ch] only needs to interpret a subset of
DWARF opcodes in gas. More details follow.
[Set 1, Interpreted] The following opcodes are interpreted:
- DW_CFA_advance_loc
- DW_CFA_def_cfa
- DW_CFA_def_cfa_register
- DW_CFA_def_cfa_offset
- DW_CFA_offset
- DW_CFA_remember_state
- DW_CFA_restore_state
- DW_CFA_restore
[Set 2, Bypassed] The following opcodes are acknowledged but are not
necessary for generating SFrame unwind info:
- DW_CFA_undefined
- DW_CFA_same_value
Anything else apart from the two above-mentioned sets is skipped
altogether. This means that any function containing a CFI directive not
in Set 1 or Set 2 above, will not have any SFrame unwind information
generated for them. Holes in instructions covered by FREs of a single
FDE are not representable in the SFrame unwind format.
As few examples, following opcodes are not processed for .sframe
generation, and are skipped:
- .cfi_personality*
- .cfi_*lsda
- .cfi_escape
- .cfi_negate_ra_state
- ...
Not processing .cfi_escape, .cfi_negate_ra_state will cause SFrame
unwind information to be absent for SFrame FDEs that contain these CFI
directives, hence affecting the asynchronicity.
x86-64 and aarch64 backends need to have a few new definitions and
functions for .sframe generation. These provide gas with architecture
specific information like the SP/FP/RA register numbers and an
SFrame-specific ABI marker.
Lastly, the patch also implements an optimization for size, where
specific fragments containing SFrame FRE start address and SFrame FDE
function are fixed up. This is similar to other similar optimizations
in gas, where fragments are sized and fixed up when the associated
symbols can be resolved. This optimization is controlled by a #define
SFRAME_FRE_TYPE_SELECTION_OPT and should be easy to turn off if needed.
The optimization is on by default for both x86_64 and aarch64.
ChangeLog:
* gas/Makefile.am: Include gen-sframe.c and sframe-opt.c.
* gas/Makefile.in: Regenerated.
* gas/as.h (enum _relax_state): Add new state rs_sframe.
(sframe_estimate_size_before_relax): New function.
(sframe_relax_frag): Likewise.
(sframe_convert_frag): Likewise.
* gas/config/tc-aarch64.c (aarch64_support_sframe_p): New
definition.
(aarch64_sframe_ra_tracking_p): Likewise.
(aarch64_sframe_cfa_ra_offset): Likewise.
(aarch64_sframe_get_abi_arch): Likewise.
(md_begin): Set values of sp/fp/ra registers.
* gas/config/tc-aarch64.h (aarch64_support_sframe_p): New
declaration.
(support_sframe_p): Likewise.
(SFRAME_CFA_SP_REG): Likewise.
(SFRAME_CFA_FP_REG): Likewise.
(SFRAME_CFA_RA_REG): Likewise.
(aarch64_sframe_ra_tracking_p): Likewise.
(sframe_ra_tracking_p): Likewise.
(aarch64_sframe_cfa_ra_offset): Likewise.
(sframe_cfa_ra_offset): Likewise.
(aarch64_sframe_get_abi_arch): Likewise.
(sframe_get_abi_arch): Likewise.
* gas/config/tc-i386.c (x86_support_sframe_p): New definition.
(x86_sframe_ra_tracking_p): Likewise.
(x86_sframe_cfa_ra_offset): Likewise.
(x86_sframe_get_abi_arch): Likewise.
* gas/config/tc-i386.h (x86_support_sframe_p): New declaration.
(support_sframe_p): Likewise.
(SFRAME_CFA_SP_REG): Likewise.
(SFRAME_CFA_FP_REG): Likewise.
(x86_sframe_ra_tracking_p): Likewise.
(sframe_ra_tracking_p): Likewise.
(x86_sframe_cfa_ra_offset): Likewise.
(sframe_cfa_ra_offset): Likewise.
(x86_sframe_get_abi_arch): Likewise.
(sframe_get_abi_arch): Likewise.
* gas/config/tc-xtensa.c (unrelaxed_frag_max_size): Add case for
rs_sframe.
* gas/doc/as.texi: Add .sframe to the documentation for
.cfi_sections.
* gas/dw2gencfi.c (cfi_finish): Create a .sframe section.
* gas/dw2gencfi.h (CFI_EMIT_sframe): New definition.
* gas/write.c (cvt_frag_to_fill): Handle rs_sframe.
(relax_segment): Likewise.
* gas/gen-sframe.c: New file.
* gas/gen-sframe.h: New file.
* gas/sframe-opt.c: New file.
This tidies memory used by the two x86 gas string hash tables before
exiting. I'm using a two-pronged approach, firstly the obvious call
to htab_delete plus telling the libiberty/hashtab.c infrastructure to
free tuples generated by str_hash_insert, and secondly putting the x86
core_optab memory on the notes obstack. It would be possible to free
core_optab memory by using a custom hash table del_f on x86, as I do
for arc, but a later patch will move all the string hash memory to the
notes obstack.
* config/tc-i386.c (md_begin): Use notes_alloc for core_optab.
(386_md_end): New function.
* config/tc-i386.h (386_md_end): Declare.
(md_end): Define.
* hash.h (str_htab_create): Pass free as del_f.
This is in preparation of dropping the leading . from the strings.
While there also move PROCESSOR_GENERIC{32,64} from the middle of AMD
entries to near the top.
Neither non-64-bit code nor uses with a non-zero offset from a symbol
should be converted to PLT32, as an eventual PLT entry would not express
what was requested.
The result of running etc/update-copyright.py --this-year, fixing all
the files whose mode is changed by the script, plus a build with
--enable-maintainer-mode --enable-cgen-maint=yes, then checking
out */po/*.pot which we don't update frequently.
The copy of cgen was with commit d1dd5fcc38ead reverted as that commit
breaks building of bfp opcodes files.
.tfloat output should always be 10 bytes without padding, independent
of psABIs. In glibc, x86 assembly codes expect 10-byte .tfloat output.
This also reduces .ds.x output and .tfloat output with hex input from
12 bytes to 10 bytes to match .tfloat output.
PR gas/28230
* NEWS: Mention changes of .ds.x output and .tfloat output with
hex input.
* config/tc-i386.c (x86_tfloat_pad): Removed.
* config/tc-i386.h (X_PRECISION_PAD): Changed to 0.
(x86_tfloat_pad): Removed.
* testsuite/gas/i386/fp.s: If NO_TFLOAT_PADDING isn't defined,
add explicit paddings after .tfloat, .ds.x, .dc.x and .dcb.x
directives.
* testsuite/gas/i386/i386.exp (ASFLAGS): Append
"--defsym NO_TFLOAT_PADDING=1" when running the fp test.
The ELF psABI-s are quite clear here: On 32-bit the underlying data type
is 12 bytes long (with 2 bytes of trailing padding), while on 64-bit it
is 16 bytes long (with 6 bytes of padding). Make s_space() capable of
handling 'x' (and 'p') type floating point being other than 12 bytes
wide (also adjusting documentation). This requires duplicating the
definition of X_PRECISION in the target speciifc header; the compiler
would complain if this was out of sync with config/atof-ieee.c.
Note that for now padding space doesn't get separated from actual
storage, which means that things will work correctly only for little-
endian cases, and which also means that by specifying large enough
numbers padding space can be set to non-zero. Since the logic is needed
for a single little-endian architecture only for now, I'm hoping that
this might be acceptable for the time being; otherwise the change will
become more intrusive.
Note also that this brings the emitted data size of .ds.x vs .tfloat in
line for non-ELF targets as well; the issue will be even more obvious
when further taking into account a subsequent patch fixing .dc.x/.dcb.x
(where output sizes currently differ depending on input format).
Extend existing x86 testcases.
The ELF psABI-s are quite clear here: On 32-bit the data type is 12
bytes long (with 2 bytes of trailing padding), while on 64-bit it is 16
bytes long (with 6 bytes of padding). Make ieee_md_atof() capable of
handling such padding, and specify the needed padding for x86 (leaving
non-ELF targets alone for now). Split the existing x86 testcase.
Always define TC_PARSE_CONS_EXPRESSION to properly wrap constants for
all x86 targets.
* config/tc-i386.c (x86_cons): Handle GOT/PLT relocations only
if needed.
* config/tc-i386.h (TC_PARSE_CONS_EXPRESSION): Always define.
Now that lex_got() is uniform for all targets using it, permit COFF
targets to also use @secrel32 with, in particular, .long. This is more
natural than the custom .secrel32 directive, and also allows more
flexibility (the "+six" form of the two added test lines doesn't work
with a .secrel32 equivalent, in that it silently produces an unintended
relocation type).
As an extra benefit this also makes sure that data definitions in Intel
syntax mode would get treated like they do for e.g. ELF targets.
Allow a few more expression forms when the entire expression can be
resolved at assembly time. For this, i386_validate_fix() needs to
arrange for all processing of the relocation to be deferred to
tc_gen_reloc().
Define TC_FORCE_RELOCATION_ABS to force relocation against local
absolute symbol.
PR gas/25756
* config/tc-i386.h (TC_FORCE_RELOCATION_ABS): New.
* testsuite/gas/i386/localpic.s: Add a test for relocation
against local absolute symbol.
* testsuite/gas/i386/x86-64-localpic.s: Likewise.
* testsuite/gas/i386/localpic.d: Updated.
* testsuite/gas/i386/x86-64-localpic.d: Likewise.
* testsuite/gas/i386/ilp32/x86-64-localpic.d: Likewise.
According to intel SDM manual, not all compare flag-modifying instructions
are marcro-fusible with subsequent jcc instructions. For those non-fusible
instructions, -malign-branch doesn't need to align them, only jcc itself
needs to be aligned.
Here are 2 restrictions which separate macro-fusible instruction from not
Restriction 1:
If TEST/AND/CMP/ADD/SUB/INC/DEC is one of the following format:
cmp m, imm
add m, imm
sub m, imm
test m, imm
and m, imm
inc m
dec m
it is unfusible with any jcc instruction.
Restriction 2:
/* Table 3-2. Macro-Fusible Instructions in Haswell Microarchitecture
Note it also works for Skylake and Cascadelake.
---------------------------------------------------------------------
| JCC | ADD/SUB/CMP | INC/DEC | TEST/AND |
| ------ | ----------- | ------- | -------- |
| Jo | N | N | Y |
| Jno | N | N | Y |
| Jc/Jb | Y | N | Y |
| Jae/Jnb | Y | N | Y |
| Je/Jz | Y | Y | Y |
| Jne/Jnz | Y | Y | Y |
| Jna/Jbe | Y | N | Y |
| Ja/Jnbe | Y | N | Y |
| Js | N | N | Y |
| Jns | N | N | Y |
| Jp/Jpe | N | N | Y |
| Jnp/Jpo | N | N | Y |
| Jl/Jnge | Y | Y | Y |
| Jge/Jnl | Y | Y | Y |
| Jle/Jng | Y | Y | Y |
| Jg/Jnle | Y | Y | Y |
Update maybe_fused_with_jcc_p to check if operands of CMP like instructions
can be fused with condition jump.
* gas/config/tc-i386.h (i386_tc_frag_data): Add member mf_type.
(TC_FRAG_INIT): Init mf_type.
* gas/config/tc-i386.c (enum mf_jcc_kind): New enum.
(enum mf_cmp_kind): Ditto.
(maybe_fused_with_jcc_p): Add argument mf_cmp_p to get
mf_type of corresponding instructons, exclude unfusible
instructions.
(add_fused_jcc_padding_frag_p): Likewise.
(add_branch_padding_frag_p): Likewise.
(output_insn): Record mf_type for corresponding instructions.
(i386_macro_fusible_p): New function.
(i386_next_fusible_jcc_frag): Rename from i386_next_jcc_frag,
add argument cmp_fragP to return next fusible jcc frag only.
(i386_classify_machine_dependant_frag): Seperate macro-fusible
instructions from condition jump.
* gas/testsuite/gas/i386/align-branch-9.s: New file.
* gas/testsuite/gas/i386/align-branch-9.d: Ditto.
* gas/testsuite/gas/i386/x86-64-align-branch-9.s: Ditto.
* gas/testsuite/gas/i386/x86-64-align-branch-9.d: Ditto.
* gas/testsuite/gas/i386/i386.exp: Run new tests.
Add 3 command-line options to align branches within a fixed boundary
with segment prefixes or NOPs:
1. -malign-branch-boundary=NUM aligns branches within NUM byte boundary.
2. -malign-branch=TYPE[+TYPE...] specifies types of branches to align.
The supported branches are:
a. Conditional jump.
b. Fused conditional jump.
c. Unconditional jump.
d. Call.
e. Ret.
f. Indirect jump and call.
3. -malign-branch-prefix-size=NUM aligns branches with NUM segment
prefixes per instruction.
3 new rs_machine_dependent frag types are added:
1. BRANCH_PADDING. The variable size frag to insert NOP before branch.
2. BRANCH_PREFIX. The variable size frag to insert segment prefixes to
an instruction. The choices of prefixes are:
a. Use the existing segment prefix if there is one.
b. Use CS segment prefix in 64-bit mode.
c. In 32-bit mode, use SS segment prefix with ESP/EBP base register
and use DS segment prefix without ESP/EBP base register.
3. FUSED_JCC_PADDING. The variable size frag to insert NOP before fused
conditional jump.
The new rs_machine_dependent frags aren't inserted if the previous item
is a prefix or a constant directive, which may be used to hardcode an
instruction, since there is no clear instruction boundary. Segment
prefixes and NOP padding are disabled before relaxable TLS relocations
and tls_get_addr calls to keep TLS instruction sequence unchanged.
md_estimate_size_before_relax() and i386_generic_table_relax_frag() are
used to handled BRANCH_PADDING, BRANCH_PREFIX and FUSED_JCC_PADDING frags.
i386_generic_table_relax_frag() grows or shrinks sizes of segment prefix
and NOP to align the next branch frag:
1. First try to add segment prefixes to instructions before a branch.
2. If there is no sufficient room to add segment prefixes, NOP will be
inserted before a branch.
* config/tc-i386.c (_i386_insn): Add has_gotpc_tls_reloc.
(tls_get_addr): New.
(last_insn): New.
(align_branch_power): New.
(align_branch_kind): New.
(align_branch_bit): New.
(align_branch): New.
(MAX_FUSED_JCC_PADDING_SIZE): New.
(align_branch_prefix_size): New.
(BRANCH_PADDING): New.
(BRANCH_PREFIX): New.
(FUSED_JCC_PADDING): New.
(i386_generate_nops): Support BRANCH_PADDING and FUSED_JCC_PADDING.
(md_begin): Abort if align_branch_prefix_size <
MAX_FUSED_JCC_PADDING_SIZE.
(md_assemble): Set last_insn.
(maybe_fused_with_jcc_p): New.
(add_fused_jcc_padding_frag_p): New.
(add_branch_prefix_frag_p): New.
(add_branch_padding_frag_p): New.
(output_insn): Generate a BRANCH_PADDING, FUSED_JCC_PADDING or
BRANCH_PREFIX frag and terminate each frag to align branches.
(output_disp): Set i.has_gotpc_tls_reloc to TRUE for GOTPC and
relaxable TLS relocations.
(output_imm): Likewise.
(i386_next_non_empty_frag): New.
(i386_next_jcc_frag): New.
(i386_classify_machine_dependent_frag): New.
(i386_branch_padding_size): New.
(i386_generic_table_relax_frag): New.
(md_estimate_size_before_relax): Handle COND_JUMP_PADDING,
FUSED_JCC_PADDING and COND_JUMP_PREFIX frags.
(md_convert_frag): Handle BRANCH_PADDING, BRANCH_PREFIX and
FUSED_JCC_PADDING frags.
(OPTION_MALIGN_BRANCH_BOUNDARY): New.
(OPTION_MALIGN_BRANCH_PREFIX_SIZE): New.
(OPTION_MALIGN_BRANCH): New.
(md_longopts): Add -malign-branch-boundary=,
-malign-branch-prefix-size= and -malign-branch=.
(md_parse_option): Handle -malign-branch-boundary=,
-malign-branch-prefix-size= and -malign-branch=.
(md_show_usage): Display -malign-branch-boundary=,
-malign-branch-prefix-size= and -malign-branch=.
(i386_target_format): Set tls_get_addr.
(i386_cons_align): New.
* config/tc-i386.h (i386_cons_align): New.
(md_cons_align): New.
(i386_generic_table_relax_frag): New.
(md_generic_table_relax_frag): New.
(i386_tc_frag_data): Add u, padding_address, length,
max_prefix_length, prefix_length, default_prefix, cmp_size,
classified and branch_type.
(TC_FRAG_INIT): Initialize u, padding_address, length,
max_prefix_length, prefix_length, default_prefix, cmp_size,
classified and branch_type.
* doc/c-i386.texi: Document -malign-branch-boundary=,
-malign-branch= and -malign-branch-prefix-size=.
This patch is aimed a fixing large numbers of x86_64-cloudabi failures
caused by gas selecting the wrong target name.
* config/te-cloudabi.h: New file.
* config/tc-aarch64.c (aarch64_after_parse_args): Use TE_CLOUDABI
rather than TARGET_OS to select cloudabi.
* config/tc-i386.h (ELF_TARGET_FORMAT64): Define for TE_CLOUDABI.
* configure.tgt (*-*-cloudabi*): Set em=cloudabi.
ommit 3ae729d5a4
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Wed Mar 7 04:18:45 2018 -0800
x86: Rewrite NOP generation for fill and alignment
increased MAX_MEM_FOR_RS_ALIGN_CODE to 4095 which resulted in increase
of assembler time and memory usage by 5 times for inputs with many
.p2align directives, which is typical for LTO output. This patch passes
max_bytes to TC_FRAG_INIT so that MAX_MEM_FOR_RS_ALIGN_CODE can be set
as needed and tracked by backend it so that HANDLE_ALIGN can check the
maximum alignment for each rs_align_code frag. Wall time to assemble
the same cc1plus.s:
before:
423.78user 0.89system 7:05.71elapsed 99%CPU
after:
102.35user 0.27system 1:42.89elapsed 99%CPU
PR gas/24165
* frags.c (frag_var_init): Pass max_chars to TC_FRAG_INIT as
max_bytes.
* config/tc-aarch64.h (TC_FRAG_INIT): Add and pass max_bytes to
aarch64_init_frag.
* /config/tc-arm.h (TC_FRAG_INIT): And and pass max_bytes to
arm_init_frag.
* config/tc-avr.h (TC_FRAG_INIT): And and ignore max_bytes.
* config/tc-ia64.h (TC_FRAG_INIT): Likewise.
* config/tc-mmix.h (TC_FRAG_INIT): Likewise.
* config/tc-nds32.h (TC_FRAG_INIT): Likewise.
* config/tc-ns32k.h (TC_FRAG_INIT): Likewise.
* config/tc-rl78.h (TC_FRAG_INIT): Likewise.
* config/tc-rx.h (TC_FRAG_INIT): Likewise.
* config/tc-score.h (TC_FRAG_INIT): Likewise.
* config/tc-tic54x.h (TC_FRAG_INIT): Likewise.
* config/tc-tic6x.h (TC_FRAG_INIT): Likewise.
* config/tc-xtensa.h (TC_FRAG_INIT): Likewise.
* config/tc-i386.h (MAX_MEM_FOR_RS_ALIGN_CODE): Set to
(alignment ? ((1 << alignment) - 1) : 1)
(i386_tc_frag_data): Add max_bytes.
(TC_FRAG_INIT): Add and track max_bytes.
(HANDLE_ALIGN): Replace MAX_MEM_FOR_RS_ALIGN_CODE with
fragP->tc_frag_data.max_bytes.
* doc/internals.texi: Update TC_FRAG_TYPE with max_bytes.
Put back BFD_RELOC_X86_64_GOTPCREL in TC_FORCE_RELOCATION_LOCAL, which
was removed by
commit 56ceb5b540
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Thu Oct 22 04:49:20 2015 -0700
Add R_X86_64_[REX_]GOTPCRELX support to gas and ld
by accident.
Add -mx86-used-note=[yes|no] option to generate (or not) GNU property
notes with GNU_PROPERTY_X86_FEATURE_2_USED and GNU_PROPERTY_X86_ISA_1_USED
properties. If the assembly input contains no instructions, set the
GNU_PROPERTY_X86_UINT32_VALID bit in GNU_PROPERTY_X86_FEATURE_2_USED
property. Add a --enable-x86-used-note configure time option to set the
default behavior. Set the default if the configure option is not used
to "no".
* NEWS: Mention -mx86-used-note=[no|yes].
* configure.ac: Add --enable-x86-used-note. Define
DEFAULT_X86_USED_NOTE.
* config.in: Regenerated.
* configure: Likewise.
* config/tc-i386.c (x86_isa_1_used): New.
(x86_feature_2_used): Likewise.
(x86_used_note): Likewise.
(_i386_insn): Add has_regmmx, has_regxmm, has_regymm and
has_regzmm.
(build_modrm_byte): Set i.has_regmmx, i.has_regzmm.
i.has_regymm and i.has_regxmm.
(x86_cleanup): New function.
(output_insn): Update x86_isa_1_used and x86_feature_2_used.
(OPTION_X86_USED_NOTE): New.
(md_longopts): Add -mx86-used-note=.
(md_parse_option): Handle OPTION_X86_USED_NOTE.
(md_show_usage): Display -mx86-used-note=.
* config/tc-i386.h (x86_cleanup): New prototype.
(md_cleanup): New.
* doc/c-i386.texi: Document -mx86-used-note=.
Implement the '.nop SIZE[, CONTROL]' assembler directive, which emits
SIZE bytes filled with no-op instructions. SIZE is absolute expression.
The optional CONTROL byte controls how no-op instructions should be
generated. If the comma and @var{control} are omitted, CONTROL is
assumed to be zero.
For Intel 80386 and AMD x86-64 targets, CONTROL byte specifies the size
limit of a single no-op instruction. The valid values of CONTROL byte
are between 0 and 8 for 16-bit mode, between 0 and 10 for 32-bit mode,
between 0 and 11 for 64-bit mode. When 0 is used, the no-op size limit
is set to the maximum supported size.
2 new relax states, rs_space_nop and rs_fill_nop, are added to enum
_relax_state, which are similar to rs_space and rs_fill, respectively,
but they fill with no-op instructions, instead of a single byte. A
target backend must override the default md_generate_nops to generate
proper no-op instructions. Otherwise, an error of unimplemented .nop
directive will be issued whenever .nop directive is used.
* NEWS: Mention .nop directive.
* as.h (_relax_state): Add rs_space_nop and rs_fill_nop.
* read.c (potable): Add .nop.
(s_nop): New function.
* read.h (s_nop): New prototype.
* write.c (cvt_frag_to_fill): Handle rs_space_nop and
rs_fill_nop.
(md_generate_nops): New function.
(relax_segment): Likewise.
(write_contents): Use md_generate_nops for rs_fill_nop.
* config/tc-i386.c (alt64_11): New.
(alt64_patt): Likewise.
(md_convert_frag): Handle rs_space_nop.
(i386_output_nops): New function.
(i386_generate_nops): Likewise.
(i386_align_code): Call i386_output_nops.
* config/tc-i386.h (i386_generate_nops): New.
(md_generate_nops): Likewise.
* doc/as.texinfo: Document .nop directive.
* testsuite/gas/i386/i386.exp: Run .nop directive tests.
* testsuite/gas/i386/nop-1.d: New file.
* testsuite/gas/i386/nop-1.s: Likewise.
* testsuite/gas/i386/nop-2.d: Likewise.
* testsuite/gas/i386/nop-2.s: Likewise.
* testsuite/gas/i386/nop-3.d: Likewise.
* testsuite/gas/i386/nop-3.s: Likewise.
* testsuite/gas/i386/nop-4.d: Likewise.
* testsuite/gas/i386/nop-4.s: Likewise.
* testsuite/gas/i386/nop-5.d: Likewise.
* testsuite/gas/i386/nop-5.s: Likewise.
* testsuite/gas/i386/nop-6.d: Likewise.
* testsuite/gas/i386/nop-6.s: Likewise.
* testsuite/gas/i386/nop-bad-1.l: Likewise.
* testsuite/gas/i386/nop-bad-1.s: Likewise.
* testsuite/gas/i386/x86-64-nop-1.d: Likewise.
* testsuite/gas/i386/x86-64-nop-2.d: Likewise.
* testsuite/gas/i386/x86-64-nop-3.d: Likewise.
* testsuite/gas/i386/x86-64-nop-4.d: Likewise.
* testsuite/gas/i386/x86-64-nop-5.d: Likewise.
* testsuite/gas/i386/x86-64-nop-6.d: Likewise.
This patch adds support for the R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX relocations proposed in
https://groups.google.com/forum/#!topic/x86-64-abi/n9AWHogmVY0
to gas and ld. It updates gas to generate R_X86_64_GOTPCRELX,
R_X86_64_REX_GOTPCRELX if there is a REX prefix, relocation for memory
operand, foo@GOTPCREL(%rip). With the locally defined symbol, foo, we
convert
mov foo@GOTPCREL(%rip), %reg
to
lea foo(%rip), %reg
and convert
call/jmp *foo@GOTPCREL(%rip)
to
nop call foo/jmp foo nop
When PIC is false, convert
test %reg, foo@GOTPCREL(%rip)
to
test $foo, %reg
and convert
binop foo@GOTPCREL(%rip), %reg
to
binop $foo, %reg
where binop is one of adc, add, and, cmp, or, sbb, sub, xor instructions.
bfd/
* elf64-x86-64.c: Include opcode/i386.h.
(x86_64_elf_howto_table): Add R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX.
(R_X86_64_standard): Replace R_X86_64_PLT32_BND with
R_X86_64_REX_GOTPCRELX.
(x86_64_reloc_map): Add BFD_RELOC_X86_64_GOTPCRELX and
BFD_RELOC_X86_64_REX_GOTPCRELX.
(need_convert_mov_to_lea): Renamed to ...
(need_convert_load): This.
(elf_x86_64_check_relocs): Handle R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX. Replace need_convert_mov_to_lea with
need_convert_load.
(elf_x86_64_gc_sweep_hook): Handle R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX.
(elf_x86_64_size_dynamic_sections): Likewise.
(elf_x86_64_relocate_section): Likewise.
(elf_x86_64_convert_mov_to_lea): Renamed to ...
(elf_x86_64_convert_load): This. Replace need_convert_mov_to_lea
with need_convert_load. Support R_X86_64_GOTPCRELX and
R_X86_64_REX_GOTPCRELX transformations.
* reloc.c (BFD_RELOC_X86_64_GOTPCRELX): New.
(BFD_RELOC_X86_64_REX_GOTPCRELX): Likewise.
* bfd-in2.h: Regenerated.
* libbfd.h: Likewise.
gas/
* config/tc-i386.c (tc_i386_fix_adjustable): Handle
BFD_RELOC_X86_64_GOTPCRELX and BFD_RELOC_X86_64_REX_GOTPCRELX.
(tc_gen_reloc): Likewise.
(i386_validate_fix): Generate BFD_RELOC_X86_64_GOTPCRELX or
BFD_RELOC_X86_64_REX_GOTPCRELX if fx_tcbit2 is set.
* config/tc-i386.h (TC_FORCE_RELOCATION_LOCAL): Also return
true for BFD_RELOC_X86_64_GOTPCRELX and
BFD_RELOC_X86_64_REX_GOTPCRELX.
gas/testsuite/
* gas/i386/i386.exp: Run x86-64-gotpcrel.
* gas/i386/x86-64-gotpcrel.d: New file.
* gas/i386/x86-64-gotpcrel.s: Likewise.
* gas/i386/ilp32/x86-64-gotpcrel.d: Likewise.
* gas/i386/x86-64-localpic.d: Replace R_X86_64_GOTPCREL with
R_X86_64_REX_GOTPCRELX.
* gas/i386/ilp32/x86-64-localpic.d: Likewise.
include/elf/
* x86-64.h (R_X86_64_GOTPCRELX): New.
(R_X86_64_REX_GOTPCRELX): Likewise.
ld/testsuite/
* ld-ifunc/ifunc-5r-local-x86-64.d: Replace R_X86_64_GOTPCREL
with R_X86_64_REX_GOTPCRELX.
* ld-x86-64/plt-main1.rd: Likewise.
* ld-x86-64/plt-main3.rd: Likewise.
* ld-x86-64/plt-main4.rd: Likewise.
* ld-x86-64/gotpcrel1.dd: New file.
* ld-x86-64/gotpcrel1.out: Likewise.
* ld-x86-64/gotpcrel1a.S: Likewise.
* ld-x86-64/gotpcrel1b.c: Likewise.
* ld-x86-64/gotpcrel1c.c: Likewise.
* ld-x86-64/gotpcrel1d.S: Likewise.
* ld-x86-64/load1.s: Likewise.
* ld-x86-64/load1a.d: Likewise.
* ld-x86-64/load1b.d: Likewise.
* ld-x86-64/load1c.d: Likewise.
* ld-x86-64/load1d.d: Likewise.
* ld-x86-64/x86-64.exp: Run load1a, load1b, load1c and load1d
tests. Run gotpcrel1 test.
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.
