Commit Graph

119277 Commits

Author SHA1 Message Date
Jan Beulich
fd05d6b739 gas: adjust impossible/bogus M68K/MRI special case when scrubbing
State 1 is uniformly handled further up. And it is highly questionable
that in state 10 (i.e. after having seen not only a possible label, but
also an opcode), which is about to go away anyway, a line comment char
could still be meant to take effect. With the state checking dropped,
the immediately preceding logic can then also be simplified.
2024-07-19 11:54:45 +02:00
Jan Beulich
0d96d156ac gas: consistently drop trailing whitespace when scrubbing
From especially the checks for the two separator forms it appears to
follow that the construct being touched is about trailing whitespace. In
such a case, considering that for many targets ordinary and line comment
chars overlap, take into account that line comment chars override
ordinary ones in lex[] (logic elsewhere in do_scrub_chars() actually
depends on that ordering, and also accounts for this overriding).

Plus of course IS_NEWLINE() would better also be consulted. Note also
that the DOUBLESLASH_LINE_COMMENTS change should generally have no
effect just yet; it's a prereq for a later change but better fits here.

Leave respective comments as well, and update documentation to correct
which comment form is actually replaced by a single blank (i.e. neither
the ones starting with what {,tc_}comment_chars[] has nor the ones
starting with what line_comment_chars[] has).
2024-07-19 11:54:09 +02:00
Jan Beulich
da0fa10a4e gas: drop tic6x scrubber special case
Two successive PUT() without a state change in between can't be right:
The first PUT() may take the "goto tofull" path, leading to the
subsequent character being processed later in the previously set state
(1 in this case), rather than the state we were in upon entry to the
switch() (13 in this case).

However, the original purpose of that logic appears to be to not mistake
"|| ^" for "||^". This effect, sadly, looks to not have been achieved.
Therefore drop the special case altogether; something that actually
achieves the (presumably) intended effect may then be introduced down
the road.
2024-07-19 11:53:24 +02:00
Jan Beulich
75d0166b71 gas: pre-init the scrubber's lex[]
While we can't - unlike an old comment suggests - do this fully, we can
certainly do part of this at compile time.

Since it's adjacent, also drop the unnecessary forward declaration of
process_escape().
2024-07-19 11:52:50 +02:00
Jan Beulich
3fea91b17d x86: accept whitespace inside curly braces
Other than documented /**/ comments currently aren't really converted to
a single space, at least not for x86 in its most common configurations.
That'll be fixed subsequently, at which point blanks may appear where so
far none were expected. Furthermore not permitting blanks immediately
inside curly braces wasn't quite logical anyway - such constructs are
composite ones, and hence components ought to have been permitted to be
separated by whitespace from the very beginning.

With this we also don't care anymore whether the scrubber would remove
whitespace around curly braces, so move them from extra_symbol_chars[]
to operand_special_chars[].

Note: The new testcase doesn't actually exercise much (if any) of the
added code. It is being put in place to ensure that subsequently, when
that code actually comes into play, behavior remains the same.
2024-07-19 11:52:21 +02:00
Jan Beulich
0ff4e567db x86: undo '{' being a symbol-start character
Having it that way has undue side effects, in permitting not only
pseudo-prefixes to be parsed correctly, but also permitting odd symbol
names which ought to be possible only when quoted.  Borrow what other
architectures do: Put in place an "unrecognized line" hook to parse off
any pseudo prefixes, while using the "start of line" hook to reject ones
not actually followed by an insn. For that parsing re-use parse_insn()
in yet a slightly different mode (dealing with only pseudo-prefixes).

With that, pp may no longer be cleared from init_globals(), but instead
needs clearing after a line was fully processed. Since md_assemble() has
pretty many return paths, convert that into a local helper, with a
trivial wrapper around it.

Similarly pp may no longer be updated (by check_register()) when
processing anything other than insn operands. To be able to (easily)
recognize the case, clear current_templates.start when done with an insn
(or with .insn).
2024-07-19 11:44:07 +02:00
Jan Beulich
e3bfcef3f2 x86: split pseudo-prefix state from i386_insn
Subsequently we will want to update that ahead of md_assemble(), with
that function needing to take into account such earlier updating.
Therefore it'll want resetting separately from i.
2024-07-19 11:43:37 +02:00
Jan Beulich
8ba953169c x86/APX: add CMPcc/CTESTcc cases to noreg64 tests
This was missed when support for the insns was added. Just like for
DATA16, in

	rex64 neg (%rax)
	rex64 neg (%r16)
	rex64 {nf} neg (%rax)

it is not logical why the last one shouldn't be permitted. Bypassing
that check requires other adjustments, though, to actually properly
consume (and then squash) the prefix.
2024-07-19 10:54:22 +02:00
zhangxianting
88e7d674ef bfin: free the allocated memory 2024-07-19 10:53:12 +02:00
Maciej W. Rozycki
6eac8a3064 MIPS/GAS/testsuite: Also verify trap expansions of multiplication macros
Provide 'mul' test variants for trap expansions as requested by the
'-trap' command-line option, and run them across all the compatible
architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
37b8310680 MIPS/GAS/testsuite: Split mul test into 32-bit and 64-bit parts
Enable full 32-bit and 64-bit multiplication macro verification, by
splitting the 'mul' test into two parts respectively, and run them
across all the compatible architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
37ed5bd27a MIPS/GAS/testsuite: Run the mul macro test across architectures
The multiplication macros expand differently based on the ISA chosen, so
run the 'mul' macro test across compatible architectures, adopting the
'mul-ilocks' test orphaned by commit 23fce1e311 ("MIPS16 intermix test
failure"), <https://sourceware.org/ml/binutils/2009-01/msg00335.html>,
and providing coverage for the expansion variants.

Only run from MIPS III up for now and remove the ISA override from the
source, so that the 64-bit instructions are covered for individual
64-bit architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
dec718565a MIPS/GAS/testsuite: Also verify trap expansions of division macros
Provide 'div' test variants for trap expansions as requested by the
'-trap' command-line option, and run them across all the compatible
architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
b734aebe68 MIPS/GAS/testsuite: Split div test into 32-bit and 64-bit parts
Enable full 32-bit and 64-bit division macro verification, by splitting
the 'div' test into two parts respectively, and run them across all the
compatible architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
a70e2bc4fc MIPS/GAS/testsuite: Run the div macro test across architectures
The division macros expand differently depending on the ISA selected, so
run the 'div' macro test across compatible architectures, adopting the
'div-ilocks' test orphaned by commit 23fce1e311 ("MIPS16 intermix test
failure"), <https://sourceware.org/ml/binutils/2009-01/msg00335.html>,
and providing coverage for the expansion variants.

Only run from MIPS III up for now and remove the ISA override from the
source, so that the 64-bit instructions are covered for individual
64-bit architectures.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
875ac09b12 MIPS/GAS: Handle --trap command-line option dynamically
We have an ISA check for the '--trap' command-line option that reports
its incompatibility with the MIPS I architecture.  It doesn't prevent
trap instructions from being enabled though, so when attempt is made to
emit one in an expansion of one of the division or multiplication macros
an assertion failure triggers:

.../gas/testsuite/gas/mips/brtr-opt.s: Assembler messages:
.../gas/testsuite/gas/mips/brtr-opt.s:3: Error: trap exception not supported at ISA 1
.../gas/testsuite/gas/mips/brtr-opt.s:9: Warning: divide by zero
.../gas/testsuite/gas/mips/brtr-opt.s:9: Internal error in macro_build at .../gas/config/tc-mips.c:9064.
Please report this bug.

The same assertion failure triggers without an earlier error message
when the initial ISA is compatible with the '--trap', however at the
time an attempt is made to emit a trap instruction from a division or
multiplication macro the ISA has been changed by a '.set' pseudo-op to
an incompatible one.

With the way the situations are mishandled it seems unlikely that anyone
relies on the current semantics and a sane approach is to decide on the
fly according to the currently selected ISA as to whether to emit trap
or breakpoint instructions in the case where '--trap' has been used.

Change our code to do so then and clarify that in the manual, which is
not explicit about how '--trap' is handled with a changing ISA.  Mention
the change in NEWS too since it's a applies to a user option.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
5dd9c473f6 MIPS/GAS/testsuite: Add R10000 CPU architecture
Add a fully interlocked MIPS IV CPU so that we can have coverage for
MIPS IV instruction sequences with and without instruction separation
required for a HI/LO data anti-dependency.
2024-07-19 09:42:56 +01:00
Maciej W. Rozycki
71ddc7006b MIPS/GAS/testsuite: Reorder R5900 CPU architecture definition
The R5900 CPU architecture is based on MIPS III, so move it ahead of
MIPS IV CPU architecture definitions.  No functional change.
2024-07-19 09:42:56 +01:00
Indu Bhagat
0331cd9c51 gas: aarch64: testsuite: add new tests for SCFI
Similar to the x86_64 testcases, some .s files contain the corresponding
CFI directives.  This helps in validating the synthesized CFI by running
those tests with and without the --scfi=experimental command line
option.

GAS issues some diagnostics, enabled by default, with
--scfi=experimental.  The diagnostics have been added with an intent to
help user correct inadvertent errors in their hand-written asm.  An
error is issued when GAS finds that input asm is not amenable to
accurate CFI synthesis.  The existing scfi-diag-*.s tests in the
gas/testsuite/gas/scfi/x86_64 directory test some SCFI diagnostics
already:

      - (#1) "Warning: SCFI: Asymetrical register restore"
      - (#2) "Error: SCFI: usage of REG_FP as scratch not supported"
      - (#3) "Error: SCFI: unsupported stack manipulation pattern"
      - (#4) "Error: untraceable control flow for func 'XXX'"

In the newly added aarch64 testsuite, further tests for additional
diagnostics have been added:
 - scfi-diag-1.s in this patch highlights an aarch64-specific diagnostic:
   (#5) "Warning: SCFI: ignored probable save/restore op with reg offset"

Additionally, some testcases are added to showcase the (currently)
unsupported patterns, e.g., scfi-unsupported-1.s
        mov     x16, 4384
        sub     sp, sp, x16

gas/testsuite/:
	* gas/scfi/README: Update comment to include aarch64.
	* gas/scfi/aarch64/scfi-aarch64.exp: New file.
	* gas/scfi/aarch64/ginsn-arith-1.l: New test.
	* gas/scfi/aarch64/ginsn-arith-1.s: New test.
	* gas/scfi/aarch64/ginsn-cofi-1.l: New test.
	* gas/scfi/aarch64/ginsn-cofi-1.s: New test.
	* gas/scfi/aarch64/ginsn-ldst-1.l: New test.
	* gas/scfi/aarch64/ginsn-ldst-1.s: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-1.d: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-1.l: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-1.s: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-2.d: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-2.l: New test.
	* gas/scfi/aarch64/scfi-callee-saved-fp-2.s: New test.
	* gas/scfi/aarch64/scfi-cb-1.d: New test.
	* gas/scfi/aarch64/scfi-cb-1.l: New test.
	* gas/scfi/aarch64/scfi-cb-1.s: New test.
	* gas/scfi/aarch64/scfi-cfg-1.d: New test.
	* gas/scfi/aarch64/scfi-cfg-1.l: New test.
	* gas/scfi/aarch64/scfi-cfg-1.s: New test.
	* gas/scfi/aarch64/scfi-cfg-2.d: New test.
	* gas/scfi/aarch64/scfi-cfg-2.l: New test.
	* gas/scfi/aarch64/scfi-cfg-2.s: New test.
	* gas/scfi/aarch64/scfi-cfg-3.d: New test.
	* gas/scfi/aarch64/scfi-cfg-3.l: New test.
	* gas/scfi/aarch64/scfi-cfg-3.s: New test.
	* gas/scfi/aarch64/scfi-cfg-4.l: New test.
	* gas/scfi/aarch64/scfi-cfg-4.s: New test.
	* gas/scfi/aarch64/scfi-cond-br-1.d: New test.
	* gas/scfi/aarch64/scfi-cond-br-1.l: New test.
	* gas/scfi/aarch64/scfi-cond-br-1.s: New test.
	* gas/scfi/aarch64/scfi-diag-1.l: New test.
	* gas/scfi/aarch64/scfi-diag-1.s: New test.
	* gas/scfi/aarch64/scfi-diag-2.l: New test.
	* gas/scfi/aarch64/scfi-diag-2.s: New test.
	* gas/scfi/aarch64/scfi-diag-3.l: New test.
	* gas/scfi/aarch64/scfi-diag-3.s: New test.
	* gas/scfi/aarch64/scfi-ldrp-1.d: New test.
	* gas/scfi/aarch64/scfi-ldrp-1.l: New test.
	* gas/scfi/aarch64/scfi-ldrp-1.s: New test.
	* gas/scfi/aarch64/scfi-ldrp-2.d: New test.
	* gas/scfi/aarch64/scfi-ldrp-2.l: New test.
	* gas/scfi/aarch64/scfi-ldrp-2.s: New test.
	* gas/scfi/aarch64/scfi-ldstnap-1.d: New test.
	* gas/scfi/aarch64/scfi-ldstnap-1.l: New test.
	* gas/scfi/aarch64/scfi-ldstnap-1.s: New test.
	* gas/scfi/aarch64/scfi-strp-1.d: New test.
	* gas/scfi/aarch64/scfi-strp-1.l: New test.
	* gas/scfi/aarch64/scfi-strp-1.s: New test.
	* gas/scfi/aarch64/scfi-strp-2.d: New test.
	* gas/scfi/aarch64/scfi-strp-2.l: New test.
	* gas/scfi/aarch64/scfi-strp-2.s: New test.
	* gas/scfi/aarch64/scfi-unsupported-1.l: New test.
	* gas/scfi/aarch64/scfi-unsupported-1.s: New test.
	* gas/scfi/aarch64/scfi-unsupported-2.l: New test.
	* gas/scfi/aarch64/scfi-unsupported-2.s: New test.
2024-07-18 20:54:14 -07:00
Indu Bhagat
29085f7243 gas: aarch64: add experimental support for SCFI
For synthesizing CFI (SCFI) for hand-written asm, the SCFI machinery in
GAS works on the generic GAS insns (ginsns).  This patch adds support in
the aarch64 backend to create ginsns for a subset of the supported
machine instructions.  The subset includes the minimal necessary
instructions to ensure SCFI correctness:

- Any potential register saves and unsaves.  Hence, process instructions
  belonging to a variety of iclasses involving str, ldr, stp, ldp.
- Any change of flow instructions.  This includes all conditional and
  unconditional branches, call (bl, blr, etc.) and return.
- Most importantly, any instruction that could affect the two registers
  of interest: REG_SP, REG_FP.  This set includes all pre-indexed and
  post-indexed memory operations, with writeback, on the stack.  This
  set must also include other instructions (e.g., arithmetic insns)
  where the destination register is one of the afore-mentioned registers.

With respect to callee-saved registers in Aarch64, FP/Advanced SIMD
registers D8-D15 are included along with the relevant GPRs.  Calculating
offsets for loads and stores especially for Q registers needs special
attention here.

As an example,
   str q8, [sp, #16]
On big-endian:
   STR Qn stores as a 128-bit integer (MSB first), hence, should record
   D8 as being saved at sp+24 rather than sp+16.
On little-endian:
   should record D8 as being saved at sp+16

D8-D15 are the low 64 bits of Q8-Q15, and of Z8-Z15 if SVE is used;
hence, they remain "interesting" for SCFI purposes in such cases.  A CFI
save slot always represents the low 64 bits, regardless of whether a
save occurs on D, Q or Z registers.  Currently, the ginsn creation
machinery can handle D and Q registers on little-endian and big-endian.

Apart from creating ginsn, another key responsibility of the backend is
to make sure there are safeguards in place to detect and alert if an
instruction of interest may have been skipped.  This is done via
aarch64_ginsn_unhandled () (similar to the x86 backend).  This function
, hence, is also intended to alert when future ISA changes may otherwise
render SCFI results incorrect, because of missing ginsns for the newly
added machine instructions.

At this time, becuase of the complexities wrt endianness in handling Z
register usage, skip sve_misc opclass altogether for now.  The SCFI
machinery will error out (using the aarch64_ginsn_unhandled () code
path) though if Z register usage affects correctness.

The current SCFI machinery does not currently synthesize the
PAC-related, aarch64-specific CFI directives: .cfi_b_key_frame.  The
support for this is planned for near future.

SCFI is enabled for ELF targets only.

gas/
	* config/tc-aarch64-ginsn.c: New file.
	* config/tc-aarch64.c (md_assemble): Include tc-aarch64-ginsn.c
	file.  Invoke aarch64_ginsn_new.
	* config/tc-aarch64.h (TARGET_USE_GINSN): Define for SCFI
	enablement.
	(TARGET_USE_SCFI): Likewise.
	(SCFI_MAX_REG_ID): New definition.
	(REG_FP): Likewise.
	(REG_LR): Likewise.
	(REG_SP): Likewise.
	(SCFI_INIT_CFA_OFFSET): Likewise.
	(SCFI_CALLEE_SAVED_REG_P): Likewise.
	(aarch64_scfi_callee_saved_p): New declaration.
2024-07-18 20:54:14 -07:00
Indu Bhagat
002ac05902 opcodes: aarch64: enforce checks on subclass flags in aarch64-gen.c
Enforce some checks on the newly added subclass flags:
  - If a subclass is set of one insn of an iclass, every insn of that
    iclass must have non-zero subclass field.
  - For all other iclasses, the subclass bits are zero for all insns.

include/
        * opcode/aarch64.h (enum aarch64_insn_class): Identify the
	maximum iclass enum value.

opcodes/
        * aarch64-gen.c (iclass_has_subclasses_p): New array of bool.
        (read_table): Enforce checks on subclass flags.
2024-07-18 20:54:14 -07:00
Indu Bhagat
5a4546190c opcodes: aarch64: denote subclasses for insns of iclass dp_2src
For detecting irg, add a subclass to identify it in the set of
instructions of iclass dp_2src.

opcodes/
	* aarch64-tbl.h: Add subclass flag F_DP_TAG_ONLY for irg insn.
2024-07-18 20:54:14 -07:00
Indu Bhagat
61f82dcb03 opcodes: aarch64: add flags to denote subclasses of uncond branches
Use the two new subclass flags: F_BRANCH_CALL, F_BRANCH_RET, to indicate
call to and return from subroutine respectively.

opcodes/
	* aarch64-tbl.h: Use the new F_BRANCH_* flags.
2024-07-18 20:54:14 -07:00
Indu Bhagat
7ecbb85893 opcodes: aarch64: add flags to denote subclasses of arithmetic insns
Use the three new subclass flags: F_ARITH_ADD, F_ARITH_SUB,
F_ARITH_MOV, to indicate add, sub and mov ops respectively.

These flags for subclasses will later be used for SCFI purposes to
create appropriate ginsns.  At this time, only those iclasses relevant
to SCFI have the new subclass flags specified.

For addg and subg insns, F_SUBCLASS_OTHER is more suitable because these
operations do more than just simple add or sub.

opcodes/
    * aarch64-tbl.h: Use the new F_ARITH_* flags.
2024-07-18 20:54:14 -07:00
Indu Bhagat
0cb8f3f0c5 opcodes: aarch64: add flags to denote subclasses of ldst insns
The existing iclass information tells us the general shape and purpose
of the instructions.  In some cases, however, we need to further disect
the iclass on the basis of other finer-grain information.  E.g., for the
purpose of SCFI, we need to know whether a given insn with iclass
of ldst_* is a load or a store.

At the moment, specify subclasses for only those iclasses relevant to
SCFI: ldst_imm9, ldst_pos, ldstpair_indexed, ldstpair_off and
ldstnapair_offs.

Some insns are best tagged with F_SUBCLASS_OTHER rather than F_LDST_LOAD
or F_LDST_STORE:
  - stg* ops (as they store tag only),
  - prfm,
  - ldpsw, ldrsw (32-bit loads with signed extended value.  Not useful
    for restore operations in context of SCFI.)
  - Use F_SUBCLASS_OTHER for all QL_LDST_R8 and QL_LDST_R16 operands.
    Also use F_SUBLASS_OTHER for strb/ldrb, strh/ldrh opcodes.
    These are not full loads and stores and cannot be allowed for
    register save / restore for the purpose of SCFI.

opcodes/
    * aarch64-tbl.h: Use the new F_LDST_* flags.
2024-07-18 20:54:14 -07:00
Indu Bhagat
04521e258e include: opcodes: aarch64: define new subclasses
The existing iclass information tells us the general shape and purpose
of the instructions.  In some cases, however, we need to further disect
the iclass on the basis of other finer-grain information.  E.g., for the
purpose of SCFI, we need to know whether a given insn with iclass of
ldst_* is a load or a store.  Similarly, whether a particular arithmetic
insn is an add or sub or mov, etc.

This patch defines new flags to demarcate the insns.  Also provide an
access function for subclass lookup.

Later, we will enforce (in aarch64-gen.c) that if an iclass has at least
one instruction with a non-zero subclass, all instructions of the iclass
must have a non-zero subclass information.  If none of the defined
subclasses are applicable (or not required for SCFI purposes),
F_SUBCLASS_OTHER can be used for such instructions.

include/
        * opcode/aarch64.h (F_SUBCLASS): New flag.
        (F_SUBCLASS_OTHER): Likewise.
        (F_LDST_LOAD): Likewise.
        (F_LDST_STORE): Likewise.
        (F_ARITH_ADD): Likewise.
        (F_ARITH_SUB): Likewise.
        (F_ARITH_MOV): Likewise.
        (F_BRANCH_CALL): Likewise.
        (F_BRANCH_RET): Likewise.
	(F_DP_TAG_ONLY): Likewise.
        (aarch64_opcode_subclass_p): New definition.
2024-07-18 20:54:14 -07:00
Indu Bhagat
af4eb9e20a gas: scfi: make scfi_state_restore_reg function more precise
When the SCFI machinery detects that a register has been restored from
stack, it makes some state changes in the SCFI state object.

Prior to the patch, scfi_state_restore_reg () was setting a value of
(reg, CFI_IN_REG) for (base, state) respectively.  This was causing
issues in the cmp_scfi_state () function:
  - The default state of all (callee-saved) regs at the beginning of
    function is set to (0, CFI_UNDEFINED).
  - If a register is saved and restored on some control path, the state
    of reg is (reg, CFI_IN_REG) on that path.
  - On another control path where the register was perhaps not
    used (or saved/restored on stack) remains (0, CFI_UNDEFINED).
  - The two states should be treated equal, however, at the point in
    program after the register has been restored.

Fix this by resetting the state to (0, CFI_UNDEFINED) in
scfi_state_restore_reg ().

A testcase (scfi-cfg-4.s) for this is added in a subsequent commit.

gas/
        * scfi.c (scfi_state_restore_reg): Reset to 0, CFI_UNDEFINED
	for base, state.
2024-07-18 20:54:13 -07:00
GDB Administrator
8dcdc91182 Automatic date update in version.in 2024-07-19 00:00:19 +00:00
Matthieu Longo
05974f2467 gas: minor reformatting in command line help and doc
- help message: add a comma between the short and long option
- as doc:
  - brief summary of how to invoke gas: separate [-w] [-x] on a new line as those
  two options have nothing to do with the warning options.
  - reordering of the warning options to have the same order as the listing.
  - no-warn option description: change an "and" to a "or", as it is either the short
  or long option to use, but not both at the same time.
- remove trailing whitespaces.
2024-07-18 17:02:27 +01:00
Andrew Burgess
22836ca885 gdb: check for multiple matching build-id files
Within the debug-file-directory GDB looks for the existence of a
.build-id directory.

Within the .build-id directory GDB looks for files with the form:

  .build-id/ff/4b4142d62b399499844924d53e33d4028380db.debug

which contain the debug information for the objfile with the build-id
ff4b4142d62b399499844924d53e33d4028380db.

There appear to be two strategies for populating the .build-id
directory.  Ubuntu takes the approach of placing the actual debug
information in this directory, so
4b4142d62b399499844924d53e33d4028380db.debug is an actual file
containing the debug information.

Fedora, RHEL, and SUSE take a slightly different approach, placing the
debug information elsewhere, and then creating symlinks in the
.build-id directory back to the original debug information file.  The
actual debug information is arranged in a mirror of the filesystem
within the debug directory, as an example, if the debug-file-directory
is /usr/lib/debug, then the debug information for /bin/foo can be
found in /usr/lib/debug/bin/foo.debug.

Where this gets interesting is that in some cases a package will
install a single binary with multiple names, in this case a single
binary will be install with either hard-links, or symlinks providing
the alternative names.

The debug information for these multiple binaries will then be placed
into the /usr/lib/debug/ tree, and again, links are created so a
single file can provide debug information for each of the names that
binary presents as.  An example file system might look like this (the
[link] could be symlinks, but are more likely hard-links):

  /bin/
    foo
    bar -> foo	[ HARD LINK ]
    baz -> foo	[ HARD LINK ]
  /usr/
    lib/
      debug/
        bin/
	  foo.debug
	  bar.debug -> foo.debug	[ HARD LINK ]
	  baz.debug -> foo.debug	[ HARD LINK ]

In the .build-id tree though we have a problem.  Do we have a single
entry that links to one of the .debug files?  This would work; a user
debugging any of the binaries will find the debug information based on
the build-id, and will get the correct information, after all the
.debug files are identical (same file linked together).  But there is
one problem with this approach.

Sometimes, for *reasons* it's possible that one or more the linked
binaries might get removed, along with its associated debug
information.  I'm honestly not 100% certain under what circumstances
this can happen, but what I observe is that sometime a single name for
a binary, and its corresponding .debug entry, can be missing.  If this
happens to be the entry that the .build-id link is pointing at, then
we have a problem.  The user can no longer find the debug information
based on the .build-id link.

The solution that Fedora, RHEL, & SUSE have adopted is to add multiple
entries in the .build-id tree, with each entry pointing to a different
name within the debug/ tree, a sequence number is added to the
build-id to distinguish the multiple entries.  Thus, we might end up
with a layout like this:

  /bin/
    foo
    bar -> foo	[ HARD LINK ]
    baz -> foo	[ HARD LINK ]
  /usr/
    lib/
      debug/
        bin/
	  foo.debug
	  bar.debug -> foo.debug	[ HARD LINK ]
	  baz.debug -> foo.debug	[ HARD LINK ]
      .build-id/
        a3/
          4b4142d62b399499844924d53e33d4028380db.debug -> ../../debug/bin/foo.debug	[ SYMLINK ]
          4b4142d62b399499844924d53e33d4028380db.1.debug -> ../../debug/bin/bar.debug	[ SYMLINK ]
          4b4142d62b399499844924d53e33d4028380db.2.debug -> ../../debug/bin/baz.debug	[ SYMLINK ]

With current master GDB, debug information will only ever be looked up
via the 4b4142d62b399499844924d53e33d4028380db.debug link.  But if
'foo' and its corresponding 'foo.debug' are ever removed, then master
GDB will fail to find the debug information.

Ubuntu seems to have a much better approach for debug information
handling; they place the debug information directly into the .build-id
tree, so there only ever needs to be a single entry for any one
build-id.  I wonder if/how they handle the case where multiple names
might share a single .debug file, if one of those names is then
uninstalled, how do they know the .debug file should be retained or
not ... but I assume that problem either doesn't exist or has been
solved.

Anyway, for a while Fedora has carried a patch that handles the
build-id sequence number logic.  What's presented here is inspired by
the Fedora patch, but has some changes to fix some issues.

I'm aware that this is a patch that applies to only some (probably a
minority) of distros.  However, the logic is contained to only a
single function in build-id.c, and isn't too complex, so I'm hoping
that there wont be too many objections.

For distros that don't have build-id sequence numbers there should be
no impact.  The sequence number approach still leaves the first file
without a sequence number, and this is the first file that GDB (after
this patch) checks for.  The new logic only kicks in if the
non-sequence numbered first file exists, but is a symlink to a non
existent file; in this case GDB checks for the sequence numbered files
instead.

Tests are included.

There is a small fix needed for gdb.base/sysroot-debug-lookup.exp,
after this commit GDB now treats a target: sysroot where the target
file system is local to GDB the same as if the sysroot had no target:
prefix.  The consequence of this is that GDB now resolves a symlink
back to the real filename in the sysroot-debug-lookup.exp test where
it didn't previously.  As this behaviour is inline with the case where
there is no target: prefix I think this is fine.
2024-07-18 13:24:20 +01:00
Andrew Burgess
6d45af96ea gdbserver: add gdbserver support for vFile::stat packet
After the previous two commits, this commit adds support for the
vFile::stat packet to gdbserver.  This is pretty similar to the
handling for vFile::fstat, but instead calls 'lstat'.

There's still no users of target_fileio_stat in GDB, that will come in
a later commit.
2024-07-18 13:24:20 +01:00
Andrew Burgess
3055e3d2f1 gdb: add GDB side target_ops::fileio_stat implementation
This commit adds the GDB side of target_ops::fileio_stat.  There's an
implementation for inf_child_target, which just calls 'lstat', and
there's an implementation for remote_target, which sends a new
vFile:stat packet.

The new packet is documented.

There's still no users of target_fileio_stat as I have not yet added
support for vFile::stat to gdbserver.  If these packets are currently
sent to gdbserver then they will be reported as not supported and the
ENOSYS error code will be returned.

Reviewed-By: Eli Zaretskii <eliz@gnu.org>
2024-07-18 13:24:20 +01:00
Andrew Burgess
08a115cc1c gdb: add target_fileio_stat, but no implementations yet
In a later commit I want target_fileio_stat, that is a call that
operates on a filename rather than an open file descriptor as
target_fileio_fstat does.

This commit adds the initial framework for target_fileio_stat, I've
added the top level target function and the virtual target_ops methods
in the target_ops base class.

At this point no actual targets override target_ops::fileio_stat, so
any attempts to call this function will return ENOSYS error code.
2024-07-18 13:24:20 +01:00
Cui, Lili
3ca6c047a4 X86: Update gas/NEWS for Intel APX.
gas/ChangeLog:

        * NEWS: Added "APX_F is fully supportted" to gas/NEWS.
2024-07-18 16:00:06 +08:00
GDB Administrator
7c0de4c1e0 Automatic date update in version.in 2024-07-18 00:00:17 +00:00
Tom de Vries
0ed152c5c6 [gdb/testsuite] Fix gdb.arch/arm-pseudo-unwind.exp with unix/mthumb
When running test-case gdb.arch/arm-pseudo-unwind.exp with target board
unix/mthumb, we run into:
...
(gdb) continue^M
Continuing.^M
^M
Program received signal SIGILL, Illegal instruction.^M
0x00400f38 in ?? ()^M
(gdb) FAIL: $exp: continue to breakpoint: continue to callee
...

The test-case attempts to force arm-pseudo-unwind.c to be compiled in arm mode
using additional_flags=-marm, but that's overridden by using target board
unix/mthumb.

This causes function main to be in thumb mode, and consequently function
caller (which is called from main) is is executed as if it's in thumb mode,
while it's actually in arm mode.

Fix this by adding an intermediate function caller_trampoline in
arm-pseudo-unwind.c, and hardcoding it to arm mode using
__attribute__((target("arm"))).

Likewise for test-case gdb.arch/arm-pseudo-unwind-legacy.exp.

Tested on arm-linux.

Approved-By: Luis Machado <luis.machado@arm.com>
2024-07-17 17:04:02 +02:00
Indu Bhagat
dfeb912e16 gas: scfi: testsuite: refresh the README
Update some stale text in the README.  Add few more notes to guide
future maintenance of the testsuite.

gas/testsuite/
	* gas/scfi/README: Update text.
2024-07-16 23:34:43 -07:00
GDB Administrator
d898e0855b Automatic date update in version.in 2024-07-17 00:00:18 +00:00
Simon Marchi
d9deb60b2e gdb, gdbserver, gdbsupport: use [[noreturn]] instead of ATTRIBUTE_NORETURN
C++ 11 has a built-in attribute for this, no need to use a compat macro.

Change-Id: I90e4220d26e8f3949d91761f8a13cd9c37da3875
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
2024-07-16 18:30:45 -04:00
Simon Marchi
9153eb8a7f gdb: fix indentation in remote.c
Change-Id: If344acdf703fdd3892f73f75fc891d5473808b79
2024-07-16 14:05:14 -04:00
Simon Marchi
a7a430a68c gdb: add ATTRIBUTE_NORETURN to remote_unpush_target
My IDE (well, clangd) suggested this.  It doesn't hurt to have it.

Change-Id: If6001983c17dbed3dceebac3078c8deb12c04d6b
2024-07-16 14:03:27 -04:00
Tom de Vries
b6a5604da0 [gdb/testsuite] Simplify gdb.base/complex-parts.exp
I noticed a lot of escaping in test-case gdb.base/complex-parts.exp.

Make the test-case more readable by using:
- string_to_regexp, and
- {} instead of "".

Tested on x86_64-linux and aarch64-linux.
2024-07-16 17:22:04 +02:00
GDB Administrator
a81f4e591f Automatic date update in version.in 2024-07-16 00:00:18 +00:00
Simon Marchi
58a775a606 gdb: pass program space to overlay_invalidate_all
Make the current program space bubble up one level.

Change-Id: I5ac1e3290ad266730465cd60aa3672d45ffa6475
2024-07-15 14:40:14 -04:00
Simon Marchi
8991986e24 gdb: pass program space to objfile::make
Make the current program space reference bubble up one level.

Change-Id: Iee8b11c853c76e539c991c4785737c69e6a1925c
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00
Simon Marchi
da877546db gdb: pass program space to objfile::objfile
Make the current program space reference bubble up one level.

Change-Id: I81e45e89e0cfd87c308f801d49ae811a941348b7
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00
Simon Marchi
d1e4438fa1 gdb: pass program space to entry_point_address
Make the current program space reference bubble up one level.

Change-Id: Ifc9b8186abaefb10caf99f79ae09e526fa65c882
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00
Simon Marchi
b7513ebd18 gdb: pass program space to entry_point_address_query
Make the current program space bubble up one level.

Change-Id: Ic3ad0869ca1afe41854f605a6f7eb092fca29ff8
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00
Simon Marchi
da2732476d gdb: pass program space to objfiles_changed
Make the current program space reference bubble up one level.

Change-Id: I9b33c9e0d22c171eb1bb59ce480621b02c7b7bf7
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00
Simon Marchi
3bae94c0fb gdb: pass program space to get_current_source_symtab_and_line
Make the current program space reference bubble up one level.

Change-Id: I6ba6dc4a2cb188720cbb61b84ab5c954aac105c6
Approved-By: Tom Tromey <tom@tromey.com>
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org>
2024-07-15 14:34:12 -04:00