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2022-06-21libctf: avoid mingw warningNick Alcock1-1/+1
A missing paren led to an intended cast to avoid dependence on the size of size_t in one argument of ctf_err_warn applying to the wrong type by mistake. libctf/ChangeLog: * ctf-serialize.c (ctf_write_mem): Fix cast.
2022-06-21libctf: fix linking together multiple objects derived from the same sourceNick Alcock8-33/+280
Right now, if you compile the same .c input repeatedly with CTF enabled and different compilation flags, then arrange to link all of these together, then things misbehave in various ways. libctf may conflate either inputs (if the .o files have the same name, say if they are stored in different .a archives), or per-CU outputs when conflicting types are found: the latter can lead to entirely spurious errors when it tries to produce multiple per-CU outputs with the same name (discarding all but the last, but then looking for types in the earlier ones which have just been thrown away). Fixing this is multi-pronged. Both inputs and outputs need to be differentiated in the hashtables libctf keeps them in: inputs with the same cuname and filename need to be considered distinct as long as they have different associated CTF dicts, and per-CU outputs need to be considered distinct as long as they have different associated input dicts. Right now there is nothing tying the two together other than the CU name: fix this by introducing a new field in the ctf_dict_t named ctf_link_in_out, which (for input dicts) points to the associated per-CU output dict (if any), and for output dicts points to the associated input dict. At creation time the name used is completely arbitrary: it's only important that it be distinct if CTF dicts are distinct. So, when a clash is found, adjust the CU name by sticking the number of elements in the input on the end. At output time, the CU name will appear in the linked object, so it matters a little more that it look slightly less ugly: in conflicting cases, append an incrementing integer, starting at 0. This naming scheme is not very helpful, but it's hard to see what else we can do. The input .o name may be the same. The input .a name is not even visible to ctf_link, and even *that* might be the same, because .a's can contain many members with the same name, all of which participate in the link. All we really know is that the two have distinct dictionaries with distinct types in them, and at least this way they are all represented, any any symbols, variables etc referring to those types are accurately stored. (As a side-effect this also fixes a use-after-free and double-free when errors are found during variable or symbol emission.) Use the opportunity to prevent a couple of sources of problems, to wit changing the active CU mappings when a link has already been done (no effect on ld, which doesn't use CU mappings at all), and causing multiple consecutive ctf_link's to have the same net effect as just doing the last one (no effect on ld, which only ever does one ctf_link) rather than having the links be a sort of half-incremental not-really-intended mess. libctf/ChangeLog: PR libctf/29242 * ctf-impl.h (struct ctf_dict) [ctf_link_in_out]: New. * ctf-dedup.c (ctf_dedup_emit_type): Set it. * ctf-link.c (ctf_link_add_ctf_internal): Set the input CU name uniquely when clashes are found. (ctf_link_add): Document what repeated additions do. (ctf_new_per_cu_name): New, come up with a consistent name for a new per-CU dict. (ctf_link_deduplicating): Use it. (ctf_create_per_cu): Use it, and ctf_link_in_out, and set ctf_link_in_out properly. Don't overwrite per-CU dicts with per-CU dicts relating to different inputs. (ctf_link_add_cu_mapping): Prevent per-CU mappings being set up if we already have per-CU outputs. (ctf_link_one_variable): Adjust ctf_link_per_cu call. (ctf_link_deduplicating_one_symtypetab): Likewise. (ctf_link_empty_outputs): New, delete all the ctf_link_outputs and blank out ctf_link_in_out on the corresponding inputs. (ctf_link): Clarify the effect of multiple ctf_link calls. Empty ctf_link_outputs if it already exists rather than having the old output leak into the new link. Fix a variable name. * testsuite/config/default.exp (AR): Add. (OBJDUMP): Likewise. * testsuite/libctf-regression/libctf-repeat-cu.exp: New test. * testsuite/libctf-regression/libctf-repeat-cu*: Main program, library, and expected results for the test.
2022-06-21Document how GDB searches for files when using -s, -e, and -se optionsKevin Buettner1-0/+5
GDB's documentation of the 'file' command says: If you do not specify a directory and the file is not found in the GDB working directory, GDB uses the environment variable PATH as a list of directories to search, just as the shell does when looking for a program to run. The same is true for files specified via commandline options -s, -e, and -se. This commit adds a cross reference to the file command for these options.
2022-06-21Binutils support for dwarf-5 (location and range lists related)Nick Clifton3-13/+51
* dwarf.h (struct debug_info): Add rnglists_base field. * dwarf.c (read_and_display_attr_value): Read attribute DW_AT_rnglists_base. (display_debug_rnglists_list): While handling DW_RLE_base_addressx, DW_RLE_startx_endx, DW_RLE_startx_length items, pass the proper parameter value to fetch_indexed_addr(), i.e. fetch the proper entry in .debug_addr section. (display_debug_ranges): Add rnglists_base to the .debug_rnglists base address. (load_separate_debug_files): Load .debug_addr section, if exists.
2022-06-21Default to disabling the linker warnings about execstack and RWX segments if ↵Nick Clifton4-109/+164
the target is the HPPA architecture. PR 29263 * configure.ac (ac_default_ld_warn_execstack): Default to 'no' for HPPA targets. (ac_default_ld_warn_rwx_segments): Likewise. * configure: Regenerate. * testsuite/ld-elf/elf.exp: Add the --warn-execstack command line option to the command line when running execstack tests for the HPPA target.
2022-06-21Automatic date update in version.inGDB Administrator1-1/+1
2022-06-20Move finish_print out of value_print_optionsTom Tromey3-9/+10
'finish_print' does not really belong in value_print_options -- this is consulted only when deciding whether or not to print a value, and never during the course of printing. This patch removes it from the structure and makes it a static global in infcmd.c instead. Tested on x86-64 Fedora 34.
2022-06-20PR29262, memory leak in pr_function_typeAlan Modra1-5/+2
PR 29262 * prdbg.c (pr_function_type): Free "s" on failure path.
2022-06-20PR29261, memory leak in parse_stab_struct_fieldsAlan Modra1-1/+4
PR 29261 * stabs.c (parse_stab_struct_fields): Free "fields" on failure path.
2022-06-20Automatic date update in version.inGDB Administrator1-1/+1
2022-06-19Automatic date update in version.inGDB Administrator1-1/+1
2022-06-18Fix assertion failure in copy_typeTom Tromey2-12/+12
PR exp/20630 points out a simple way to cause an assertion failure in copy_type -- but this was found in the wild a few times as well. copy_type only works for objfile-owned types, but there isn't a deep reason for this. This patch fixes the bug by updating copy_type to work for any sort of type. Better would perhaps be to finally implement type GC, but I still haven't attempted this. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=20630
2022-06-18Fix the sorting algorithm for reloc entriesTomoaki Kawada4-2/+41
The optimized insertion sort algorithm in `elf_link_adjust_relocs` incorrectly assembled "runs" from unsorted entries and inserted them to an already-sorted prefix, breaking the loop invariants of insertion sort. This commit updates the run assembly loop to break upon encountering a non-monotonic change in the sort key. PR 29259 bfd/ * elflink.c (elf_link_adjust_relocs): Ensure run being inserted is sorted. ld/ * testsuite/ld-elf/pr29259.d, * testsuite/ld-elf/pr29259.s, * testsuite/ld-elf/pr29259.t: New test.
2022-06-18gdb/python: Export nibbles to python layerEnze Li3-1/+84
This patch makes it possible to allow Value.format_string() to return nibbles output. When we set the parameter of nibbles to True, we can achieve the displaying binary values in groups of every four bits. Here's an example: (gdb) py print (gdb.Value (1230).format_string (format='t', nibbles=True)) 0100 1100 1110 (gdb) Note that the parameter nibbles is only useful if format='t' is also used. This patch also includes update to the relevant testcase and documentation. Tested on x86_64 openSUSE Tumbleweed.
2022-06-18gdb/doc: Documentation for the new print commandEnze Li2-4/+36
Document the new command "print nibbles" and add a NEWS entry.
2022-06-18gdb: Add new 'print nibbles' featureEnze Li8-3/+113
Make an introduction of a new print setting that can be set by 'set print nibbles [on|off]'. The default value if OFF, which can be changed by user manually. Of course, 'show print nibbles' is also included in the patch. The new feature displays binary values by group, with four bits per group. The motivation for this work is to enhance the readability of binary values. Here's a GDB session before this patch is applied. (gdb) print var_a $1 = 1230 (gdb) print/t var_a $2 = 10011001110 With this patch applied, we can use the new print setting to display the new form of the binary values. (gdb) print var_a $1 = 1230 (gdb) print/t var_a $2 = 10011001110 (gdb) set print nibbles on (gdb) print/t var_a $3 = 0100 1100 1110 Tested on x86_64 openSUSE Tumbleweed.
2022-06-18Automatic date update in version.inGDB Administrator1-1/+1
2022-06-17gdb: NEWS: Move LoongArch gdbserver to the correct sectionTiezhu Yang1-3/+8
commit e5ab6af52d38 ("gdbserver: Add LoongArch/Linux support") was merged into the master since GDB 12, so we should put the news in the "Changes since GDB 12" section. Thanks Tom Tromey for your correction [1], sorry for that. [1] https://sourceware.org/pipermail/gdb-patches/2022-June/190122.html Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
2022-06-17PR29256, memory leak in obj_elf_section_nameAlan Modra1-14/+18
When handling section names in quotes obj_elf_section_name calls demand_copy_C_string, which puts the name on the gas notes obstack. Such strings aren't usually freed, since obstack_free frees all more recently allocated objects as well as its arg. When handling non-quoted names, obj_elf_section_name mallocs the name. Due to the mix of allocation strategies it isn't possible for callers to free names, if that was desirable. Partially fix this by always creating names on the obstack, which is more efficient anyway. (You still can't obstack_free on error paths due to the xtensa tc_canonicalize_section_name.) Also remove a couple of cases where the name is dup'd for no good reason as far as I know. PR 29256 * config/obj-elf.c (obj_elf_section_name): Create name on notes obstack. (obj_elf_attach_to_group): Don't strdup group name. (obj_elf_section): Likewise. (obj_elf_vendor_attribute): Use xmemdup0 rather than xstrndup.
2022-06-17PR29255, memory leak in make_tempdirAlan Modra1-9/+11
PR 29255 * bucomm.c (make_tempdir, make_tempname): Free template on all failure paths.
2022-06-17PR29254, memory leak in stab_demangle_v3_argAlan Modra1-1/+4
PR 29254 * stabs.c (stab_demangle_v3_arg): Free dt on failure path.
2022-06-17Fix GDB build with GCC 4.8 & 4.9Pedro Alves2-10/+15
With gcc 4.8/4.9, we run into this build failure (and other similar ones): /home/palves/gdb/binutils-gdb/src/gdb/location.h:224:59: error: could not convert ‘{0, LINE_OFFSET_UNKNOWN}’ from ‘<brace-enclosed initializer list>’ to ‘line_offset’ struct line_offset line_offset = {0, LINE_OFFSET_UNKNOWN}; ^ The issue is that at around the GCC 4.8/4.9 era, a default member initializer prevented the struct from being an aggregate, so you cannot use aggregate initialization on them. That rule changed after GCC 4.9 and GCC 5 & later uses new rules. Fix this by not using aggregate initialization for struct line_offset. The default member initization already leaves line_offset as {0, LINE_OFFSET_UNKNOWN}, so initialization to those values can just go away. The remaining cases are of the form {0, LINE_OFFSET_NONE}, and those cases can be better rewritten to delay setting the sign field until we know we have a valid offset. Change-Id: I0506ea4a83c5fa2f15e159569db68b3b0a7509b4
2022-06-17Convert set_location_spec_string to a methodPedro Alves3-27/+19
This converts set_location_spec_string to a method of location_spec, and makes the location_spec::as_string field protected, renaming it to m_as_string along the way. Change-Id: Iccfb1654e9fa7808d0512df89e775f9eacaeb9e0
2022-06-17Convert location_spec_to_string to a methodPedro Alves8-49/+27
This converts location_spec_to_string to a method of location_spec, simplifying the code using it, as it no longer has to use std::unique_ptr::get(). Change-Id: I621bdad8ea084470a2724163f614578caf8f2dd5
2022-06-17Convert location_spec_type to a methodPedro Alves5-31/+25
This converts location_spec_type to location_spec::type(). Change-Id: Iff4cbfafb1cf3d22adfa142ff939b4a148e52273
2022-06-17Convert location_spec_empty_p to a methodPedro Alves3-15/+2
This converts location_spec_empty_p to a method of location_spec, simplifying users, as they no longer have to use std::unique_ptr::get(). Change-Id: I83381a729896f12e1c5a1b4d6d4c2eb1eb6582ff
2022-06-17Eliminate copy_location_specPedro Alves4-19/+6
copy_location_spec is just a wrapper around location_spec::clone(), so remove it and call clone() directly. This simplifies users, as they no longer have to use std::unique_ptr::get(). Change-Id: I8ce8658589460b98888283b306b315a5b8f73976
2022-06-17Eliminate the two-level data structures behind location_specsPedro Alves9-506/+452
Currently, there's the location_spec hierarchy, and then some location_spec subclasses have their own struct type holding all their data fields. I.e., there is this: location_spec explicit_location_spec linespec_location_spec address_location_spec probe_location_spec and then these separate types: explicit_location linespec_location where: explicit_location_spec has-a explicit_location linespec_location_spec has-a linespec_location This patch eliminates explicit_location and linespec_location, inlining their members in the corresponding location_spec type. The location_spec subclasses were the ones currently defined in location.c, so they are moved to the header. Since the definitions of the classes are now visible, we no longer need location_spec_deleter. Some constructors that are used for cloning location_specs, like: explicit explicit_location_spec (const struct explicit_location *loc) ... were converted to proper copy ctors. In the process, initialize_explicit_location is eliminated, and some functions that returned the "data type behind a locspec", like get_linespec_location are converted to downcast functions, like as_linespec_location_spec. Change-Id: Ia31ccef9382b25a52b00fa878c8df9b8cf2a6c5a
2022-06-17event_location -> location_specPedro Alves21-591/+605
Currently, GDB internally uses the term "location" for both the location specification the user input (linespec, explicit location, or an address location), and for actual resolved locations, like the breakpoint locations, or the result of decoding a location spec to SaLs. This is expecially confusing in the breakpoints module, as struct breakpoint has these two fields: breakpoint::location; breakpoint::loc; "location" is the location spec, and "loc" is the resolved locations. And then, we have a method called "locations()", which returns the resolved locations as range... The location spec type is presently called event_location: /* Location we used to set the breakpoint. */ event_location_up location; and it is described like this: /* The base class for all an event locations used to set a stop event in the inferior. */ struct event_location { and even that is incorrect... Location specs are used for finding actual locations in the program in scenarios that have nothing to do with stop events. E.g., "list" works with location specs. To clean all this confusion up, this patch renames "event_location" to "location_spec" throughout, and then all the variables that hold a location spec, they are renamed to include "spec" in their name, like e.g., "location" -> "locspec". Similarly, functions that work with location specs, and currently have just "location" in their name are renamed to include "spec" in their name too. Change-Id: I5814124798aa2b2003e79496e78f95c74e5eddca
2022-06-16gprofng: fix build with -Werror=format-truncationVladimir Mezentsev7-115/+27
gprofng/ChangeLog 2022-06-16 Vladimir Mezentsev <vladimir.mezentsev@oracle.com> * configure.ac: Remove -Wno-format-truncation. * src/Makefile.am: Likewise. * configure: Rebuild. * src/Makefile.in: Rebuild. * common/hwctable.c: Fix -Werror=format-truncation errors. * src/ipc.cc: Likewise. * src/parse.cc: Likewise.
2022-06-17Automatic date update in version.inGDB Administrator1-1/+1
2022-06-16[gdb/testsuite] Fix have_mpx testTom de Vries1-1/+1
When testing on openSUSE Leap 15.4 I ran into this FAIL: ... FAIL: gdb.arch/i386-mpx-map.exp: NULL address of the pointer ... and likewise for all the other mpx tests. The problem is that have_mpx is supposed to return 0, but it doesn't because it tries to match this output: ... builtin_spawn -ignore SIGHUP temp/20294/have_mpx-2-20294.x^M No MPX support^M No MPX support^M ... using: ... && ![string equal $output "No MPX support\r\n"]] ... Fix this by matching using a regexp instead. Tested on x86_64-linux.
2022-06-16use of uninitialised value in input_file_openAlan Modra1-7/+7
Triggered by a file containing just "#N" or "#A". fgets when hitting EOF before reading anything returns NULL and does not write to buf. strchr (buf, '\n') then is reading from uninitialised memory. * input-file.c (input_file_open): Don't assume buf contains zero string terminator when fgets returns NULL.
2022-06-16Always free matching vector from bfd_check_format_matchesAlan Modra10-49/+21
At least one place calling list_matching_formats failed to free the "matching" vector from bfd_check_format_matches afterwards. Fix that by calling free inside list_matching_formats. binutils/ * bucomm.c (list_matching_formats): Free arg. * addr2line.c (process_file): Adjust to suit. * ar.c (open_inarch, ranlib_touch): Likewise. * coffdump.c (main): Likewise. * nm.c (display_archive, display_file): Likewise. * objcopy.c (copy_file): Likewise. * objdump.c (display_object_bfd): Likewise. * size.c (display_bfd): Likewise. * srconv.c (main): Likewise. ld/ * ldlang.c (load_symbols): Free "matching".
2022-06-16Revert "Revert "Fix fbsd core matching""Alan Modra1-30/+10
This reverts commit 476288fa2bddecf0f0e13dee826a076309bf01fe.
2022-06-16Restore readelf -wFAlan Modra2-103/+60
Commit 94585d6d4495 resulted in readelf -wF failing with Unrecognized debug letter option 'F' binutils/ * dwarf.c (debug_dump_long_opts): Add letter. (debug_option_table): New, replacing.. (opts_table, letter_table): ..these. (dwarf_select_sections_by_names): Adjust to suit. Set do_debug_frames outside of loop. (dwarf_select_sections_by_letters): Similarly. gas/ * testsuite/gas/i386/ehinterp.d: Use readelf -wF.
2022-06-16PR29250, readelf erases CIE initial register stateAlan Modra4-38/+87
PR 29250 binutils/ * dwarf.c (display_debug_frames): Set col_type[reg] on sizing pass over FDE to cie->col_type[reg] if CIE specifies reg. Handle DW_CFA_restore and DW_CFA_restore_extended on second pass using the same logic. Remove unnecessary casts. Don't call frame_need_space on second pass over FDE. gas/ * testsuite/gas/i386/ehinterp.d, * testsuite/gas/i386/ehinterp.s: New test. * testsuite/gas/i386/i386.exp: Run it.
2022-06-16Automatic date update in version.inGDB Administrator1-1/+1
2022-06-15sim: fix BFD_VMA format arguments on 32-bit hosts [PR gdb/29184]Sergei Trofimovich3-8/+10
Noticed format mismatch when attempted to build gdb on i686-linux-gnu in --enable-64-bit-bfd mode: sim/../../sim/cris/sim-if.c:576:28: error: format '%lx' expects argument of type 'long unsigned int', but argument 4 has type 'bfd_size_type' {aka 'long long unsigned int'} [-Werror=format=] 576 | sim_do_commandf (sd, "memory region 0x%" BFD_VMA_FMT "x,0x%lx", | ^~~~~~~~~~~~~~~~~~~ 577 | interp_load_addr, interpsiz); | ~~~~~~~~~ | | | bfd_size_type {aka long long unsigned int} While at it fixed format string for time-related types.
2022-06-15Check for listeners in emit_exiting_eventTom Tromey1-0/+3
I noticed that emit_exiting_event does not check whether there are any listeners before creating the event object. All other event emitters do this, so this patch updates this one as well.
2022-06-15Add to documentation of Python 'dont_repeat' methodTom Tromey1-2/+4
PR python/28533 points out that the Python 'dont_repeat' documentation is a bit ambiguous about when the method ought to be called. This patch spells it out.
2022-06-15gdb/arm: Make sp alias for one of the other stack pointersYvan Roux1-9/+11
For Cortex-M targets, SP register is never detached from msp or psp, it always has the same value as one of them. Let GDB treat ARM_SP_REGNUM as an alias similar to what is done in hardware. Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com> Signed-off-by: Yvan Roux <yvan.roux@foss.st.com>
2022-06-15gdb/arm: Track msp and pspYvan Roux1-0/+18
For Arm Cortex-M33 with security extensions, there are 4 different stack pointers (msp_s, msp_ns, psp_s, psp_ns). To be compatible with earlier Cortex-M derivates, the msp and psp registers are aliases for one of the 4 real stack pointer registers. These are the combinations that exist: sp -> msp -> msp_s sp -> msp -> msp_ns sp -> psp -> psp_s sp -> psp -> psp_ns This means that when the GDB client is to show the value of "msp", the value should always be equal to either "msp_s" or "msp_ns". Same goes for "psp". To add a bit more context; GDB does not really use the register msp (or psp) internally, but they are part of the set of registers which are provided by the target.xml file. As a result, they will be part of the set of registers printed by the "info r" command. Without this particular patch, GDB will hit the assert in the bottom of arm_cache_get_sp_register function. Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29121 Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com> Signed-off-by: Yvan Roux <yvan.roux@foss.st.com>
2022-06-15gdb/arm: Fetch initial sp value prior to compareYvan Roux1-0/+1
For Arm Cortex-M33 with security extensions, there are 4 different stack pointers (msp_s, msp_ns, psp_s, psp_ns). In order to identify the active one, compare the values of the different stacks. The value of the initial sp register needs to be fetched to perform this comparison. Signed-off-by: Torbjörn SVENSSON <torbjorn.svensson@foss.st.com> Signed-off-by: Yvan Roux <yvan.roux@foss.st.com>
2022-06-15gdb: unify two dis_asm_read_memory functions in disasm.cAndrew Burgess2-25/+20
After the recent restructuring of the disassembler code, GDB has ended up with two identical class static functions, both called dis_asm_read_memory, with identical implementations. My first thought was to move these out of their respective classes, and just make them global functions, then I'd only need a single copy. And maybe that's the right way to go. But I disliked that by doing that I loose the encapsulation of the method with the corresponding disassembler class. So, instead, I placed the static method into its own class, and had both the gdb_non_printing_memory_disassembler and gdb_disassembler classes inherit from this new class as an additional base-class. In terms of code generated, I don't think there's any significant difference with this approach, but I think this better reflects how the function is closely tied to the disassembler. There should be no user visible changes after this commit.
2022-06-15gdb: refactor the non-printing disassemblersAndrew Burgess7-135/+170
This commit started from an observation I made while working on some other disassembler patches, that is, that the function gdb_buffered_insn_length, is broken ... sort of. I noticed that the gdb_buffered_insn_length function doesn't set up the application data field if the disassemble_info structure. Further, I noticed that some architectures, for example, ARM, require that the application_data field be set, see gdb_print_insn_arm in arm-tdep.c. And so, if we ever use gdb_buffered_insn_length for ARM, then GDB will likely crash. Which is why I said only "sort of" broken. Right now we don't use gdb_buffered_insn_length with ARM, so maybe it isn't broken yet? Anyway to prove to myself that there was a problem here I extended the disassembler self tests in disasm-selftests.c to include a test of gdb_buffered_insn_length. As I run the test for all architectures, I do indeed see GDB crash for ARM. To fix this we need gdb_buffered_insn_length to create a disassembler that inherits from gdb_disassemble_info, but we also need this new disassembler to not print anything. And so, I introduce a new gdb_non_printing_disassembler class, this is a disassembler that doesn't print anything to the output stream. I then observed that both ARC and S12Z also create non-printing disassemblers, but these are slightly different. While the disassembler in gdb_non_printing_disassembler reads the instruction from a buffer, the ARC and S12Z disassemblers read from target memory using target_read_code. And so, I further split gdb_non_printing_disassembler into two sub-classes, gdb_non_printing_memory_disassembler and gdb_non_printing_buffer_disassembler. The new selftests now pass, but otherwise, there should be no user visible changes after this commit.
2022-06-15gdb/python: implement the print_insn extension language hookAndrew Burgess12-1/+2648
This commit extends the Python API to include disassembler support. The motivation for this commit was to provide an API by which the user could write Python scripts that would augment the output of the disassembler. To achieve this I have followed the model of the existing libopcodes disassembler, that is, instructions are disassembled one by one. This does restrict the type of things that it is possible to do from a Python script, i.e. all additional output has to fit on a single line, but this was all I needed, and creating something more complex would, I think, require greater changes to how GDB's internal disassembler operates. The disassembler API is contained in the new gdb.disassembler module, which defines the following classes: DisassembleInfo Similar to libopcodes disassemble_info structure, has read-only properties: address, architecture, and progspace. And has methods: __init__, read_memory, and is_valid. Each time GDB wants an instruction disassembled, an instance of this class is passed to a user written disassembler function, by reading the properties, and calling the methods (and other support methods in the gdb.disassembler module) the user can perform and return the disassembly. Disassembler This is a base-class which user written disassemblers should inherit from. This base class provides base implementations of __init__ and __call__ which the user written disassembler should override. DisassemblerResult This class can be used to hold the result of a call to the disassembler, it's really just a wrapper around a string (the text of the disassembled instruction) and a length (in bytes). The user can return an instance of this class from Disassembler.__call__ to represent the newly disassembled instruction. The gdb.disassembler module also provides the following functions: register_disassembler This function registers an instance of a Disassembler sub-class as a disassembler, either for one specific architecture, or, as a global disassembler for all architectures. builtin_disassemble This provides access to GDB's builtin disassembler. A common use case that I see is augmenting the existing disassembler output. The user code can call this function to have GDB disassemble the instruction in the normal way. The user gets back a DisassemblerResult object, which they can then read in order to augment the disassembler output in any way they wish. This function also provides a mechanism to intercept the disassemblers reads of memory, thus the user can adjust what GDB sees when it is disassembling. The included documentation provides a more detailed description of the API. There is also a new CLI command added: maint info python-disassemblers This command is defined in the Python gdb.disassemblers module, and can be used to list the currently registered Python disassemblers.
2022-06-15gdb: add extension language print_insn hookAndrew Burgess6-4/+78
This commit is setup for the next commit. In the next commit I will add a Python API to intercept the print_insn calls within GDB, each print_insn call is responsible for disassembling, and printing one instruction. After the next commit it will be possible for a user to write Python code that either wraps around the existing disassembler, or even, in extreme situations, entirely replaces the existing disassembler. This commit does not add any new Python API. What this commit does is put the extension language framework in place for a print_insn hook. There's a new callback added to 'struct extension_language_ops', which is then filled in with nullptr for Python and Guile. Finally, in the disassembler, the code is restructured so that the new extension language function ext_lang_print_insn is called before we delegate to gdbarch_print_insn. After this, the next commit can focus entirely on providing a Python implementation of the new print_insn callback. There should be no user visible change after this commit.
2022-06-15gdb: add new base class to gdb_disassemblerAndrew Burgess4-52/+154
The motivation for this change is an upcoming Python disassembler API that I would like to add. As part of that change I need to create a new disassembler like class that contains a disassemble_info and a gdbarch. The management of these two objects is identical to how we manage these objects within gdb_disassembler, so it might be tempting for my new class to inherit from gdb_disassembler. The problem however, is that gdb_disassembler has a tight connection between its constructor, and its print_insn method. In the constructor the ui_file* that is passed in is replaced with a member variable string_file*, and then in print_insn, the contents of the member variable string_file are printed to the original ui_file*. What this means is that the gdb_disassembler class has a tight coupling between its constructor and print_insn; the class just isn't intended to be used in a situation where print_insn is not going to be called, which is how my (upcoming) sub-class would need to operate. My solution then, is to separate out the management of the disassemble_info and gdbarch into a new gdb_disassemble_info class, and make this class a parent of gdb_disassembler. In arm-tdep.c and mips-tdep.c, where we used to cast the disassemble_info->application_data to a gdb_disassembler, we can now cast to a gdb_disassemble_info as we only need to access the gdbarch information. Now, my new Python disassembler sub-class will still want to print things to an output stream, and so we will want access to the dis_asm_fprintf functionality for printing. However, rather than move this printing code into the gdb_disassemble_info base class, I have added yet another level of hierarchy, a gdb_printing_disassembler, thus the class structure is now: struct gdb_disassemble_info {}; struct gdb_printing_disassembler : public gdb_disassemble_info {}; struct gdb_disassembler : public gdb_printing_disassembler {}; In a later commit my new Python disassembler will inherit from gdb_printing_disassembler. The reason for adding the additional layer to the class hierarchy is that in yet another commit I intend to rewrite the function gdb_buffered_insn_length, and to do this I will be creating yet more disassembler like classes, however, these will not print anything, thus I will add a gdb_non_printing_disassembler class that also inherits from gdb_disassemble_info. Knowing that that change is coming, I've gone with the above class hierarchy now. There should be no user visible changes after this commit.
2022-06-15gdb/python: convert gdbpy_err_fetch to use gdbpy_refAndrew Burgess2-17/+14
Convert the gdbpy_err_fetch class to make use of gdbpy_ref, this removes the need for manual reference count management, and allows the destructor to be removed. There should be no functional change after this commit. I think this cleanup is worth doing on its own, however, in a later commit I will want to copy instances of gdbpy_err_fetch, and switching to using gdbpy_ref means that I can rely on the default copy constructor, without having to add one that handles the reference counts, so this is good preparation for that upcoming change.