This commit brings support for the DWARF line table is_stmt field to
GDB. The is_stmt field is used by the compiler when a single source
line is split into multiple assembler instructions, especially if the
assembler instructions are interleaved with instruction from other
source lines.
The compiler will set the is_stmt flag false from some instructions
from the source lines, these instructions are not a good place to
insert a breakpoint in order to stop at the source line.
Instructions which are marked with the is_stmt flag true are a good
place to insert a breakpoint for that source line.
Currently GDB ignores all instructions for which is_stmt is false.
This is fine in a lot of cases, however, there are some cases where
this means the debug experience is not as good as it could be.
Consider stopping at a random instruction, currently this instruction
will be attributed to the last line table entry before this point for
which is_stmt was true - as these are the only line table entries that
GDB tracks. This can easily be incorrect in code with even a low
level of optimisation.
With is_stmt tracking in place, when stopping at a random instruction
we now attribute the instruction back to the real source line, even
when is_stmt is false for that instruction in the line table.
When inserting breakpoints we still select line table entries for
which is_stmt is true, so the breakpoint placing behaviour should not
change.
When stepping though code (at the line level, not the instruction
level) we will still stop at instruction where is_stmt is true, I
think this is more likely to be the desired behaviour.
Instruction stepping is, of course, unchanged, stepping one
instruction at a time, but we should now report more accurate line
table information with each instruction step.
The original motivation for this work was a patch posted by Bernd
here:
https://sourceware.org/ml/gdb-patches/2019-11/msg00792.html
As part of that thread it was suggested that many issues would be
resolved if GDB supported line table views, this isn't something I've
attempted in this patch, though reading the spec, it seems like this
would be a useful feature to support in GDB in the future. The spec
is here:
http://dwarfstd.org/ShowIssue.php?issue=170427.1
And Bernd gives a brief description of the benefits here:
https://sourceware.org/ml/gdb-patches/2020-01/msg00147.html
With that all said, I think that there is benefit to having proper
is_stmt support regardless of whether we have views support, so I
think we should consider getting this in first, and then building view
support on top of this.
The gdb.cp/step-and-next-inline.exp test is based off a test proposed
by Bernd Edlinger in this message:
https://sourceware.org/ml/gdb-patches/2019-12/msg00842.html
gdb/ChangeLog:
* buildsym-legacy.c (record_line): Pass extra parameter to
record_line.
* buildsym.c (buildsym_compunit::record_line): Take an extra
parameter, reduce duplication in the line table, and record the
is_stmt flag in the line table.
* buildsym.h (buildsym_compunit::record_line): Add extra
parameter.
* disasm.c (do_mixed_source_and_assembly_deprecated): Ignore
non-statement lines.
* dwarf2/read.c (dwarf_record_line_1): Add extra parameter, pass
this to the symtab builder.
(dwarf_finish_line): Pass extra parameter to dwarf_record_line_1.
(lnp_state_machine::record_line): Pass a suitable is_stmt flag
through to dwarf_record_line_1.
* infrun.c (process_event_stop_test): When stepping, don't stop at
a non-statement instruction, and only refresh the step info when
we land in the middle of a line's range. Also add an extra
comment.
* jit.c (jit_symtab_line_mapping_add_impl): Initialise is_stmt
field.
* record-btrace.c (btrace_find_line_range): Only record lines
marked as is-statement.
* stack.c (frame_show_address): Show the frame address if we are
in a non-statement sal.
* symmisc.c (dump_symtab_1): Print the is_stmt flag.
(maintenance_print_one_line_table): Print a header for the is_stmt
column, and include is_stmt information in the output.
* symtab.c (find_pc_sect_line): Find lines marked as statements in
preference to non-statements.
(find_pcs_for_symtab_line): Prefer is-statement entries.
(find_line_common): Likewise.
* symtab.h (struct linetable_entry): Add is_stmt field.
(struct symtab_and_line): Likewise.
* xcoffread.c (arrange_linetable): Initialise is_stmt field when
arranging the line table.
gdb/testsuite/ChangeLog:
* gdb.cp/step-and-next-inline.cc: New file.
* gdb.cp/step-and-next-inline.exp: New file.
* gdb.cp/step-and-next-inline.h: New file.
* gdb.dwarf2/dw2-is-stmt.c: New file.
* gdb.dwarf2/dw2-is-stmt.exp: New file.
* gdb.dwarf2/dw2-is-stmt-2.c: New file.
* gdb.dwarf2/dw2-is-stmt-2.exp: New file.
* gdb.dwarf2/dw2-ranges-base.exp: Update line table pattern.
I touched symtab.h and was surprised to see how many files were
rebuilt. I looked into it a bit, and found that defs.h includes
gdbarch.h, which in turn includes many things.
gdbarch.h is only needed by a minority ofthe files in gdb, so this
patch removes the include from defs.h and updates the fallout.
I did "wc -l" on the files in build/gdb/.deps; this patch reduces the
line count from 139935 to 137030; so there are definitely future
build-time savings here.
Note that while I configured with --enable-targets=all, it's possible
that some *-nat.c file needs an update. I could not test all of
these. The buildbot caught a few problems along these lines.
gdb/ChangeLog
2019-07-10 Tom Tromey <tom@tromey.com>
* defs.h: Don't include gdbarch.h.
* aarch64-ravenscar-thread.c, aarch64-tdep.c, alpha-bsd-tdep.h,
alpha-linux-tdep.c, alpha-mdebug-tdep.c, arch-utils.h, arm-tdep.h,
ax-general.c, btrace.c, buildsym-legacy.c, buildsym.h, c-lang.c,
cli/cli-decode.h, cli/cli-dump.c, cli/cli-script.h,
cli/cli-style.h, coff-pe-read.h, compile/compile-c-support.c,
compile/compile-cplus.h, compile/compile-loc2c.c, corefile.c,
cp-valprint.c, cris-linux-tdep.c, ctf.c, d-lang.c, d-namespace.c,
dcache.c, dicos-tdep.c, dictionary.c, disasm-selftests.c,
dummy-frame.c, dummy-frame.h, dwarf2-frame-tailcall.c,
dwarf2expr.c, expression.h, f-lang.c, frame-base.c,
frame-unwind.c, frv-linux-tdep.c, gdbarch-selftests.c, gdbtypes.h,
go-lang.c, hppa-nbsd-tdep.c, hppa-obsd-tdep.c, i386-dicos-tdep.c,
i386-tdep.h, ia64-vms-tdep.c, interps.h, language.c,
linux-record.c, location.h, m2-lang.c, m32r-linux-tdep.c,
mem-break.c, memattr.c, mn10300-linux-tdep.c, nios2-linux-tdep.c,
objfiles.h, opencl-lang.c, or1k-linux-tdep.c, p-lang.c,
parser-defs.h, ppc-tdep.h, probe.h, python/py-record-btrace.c,
record-btrace.c, record.h, regcache-dump.c, regcache.h,
riscv-fbsd-tdep.c, riscv-linux-tdep.c, rust-exp.y,
sh-linux-tdep.c, sh-nbsd-tdep.c, source-cache.c,
sparc-nbsd-tdep.c, sparc-obsd-tdep.c, sparc-ravenscar-thread.c,
sparc64-fbsd-tdep.c, std-regs.c, target-descriptions.h,
target-float.c, tic6x-linux-tdep.c, tilegx-linux-tdep.c, top.c,
tracefile.c, trad-frame.c, type-stack.h, ui-style.c, utils.c,
utils.h, valarith.c, valprint.c, varobj.c, x86-tdep.c,
xml-support.h, xtensa-linux-tdep.c, cli/cli-cmds.h: Update.
* s390-linux-nat.c, procfs.c, inf-ptrace.c: Likewise.
This commit applies all changes made after running the gdb/copyright.py
script.
Note that one file was flagged by the script, due to an invalid
copyright header
(gdb/unittests/basic_string_view/element_access/char/empty.cc).
As the file was copied from GCC's libstdc++-v3 testsuite, this commit
leaves this file untouched for the time being; a patch to fix the header
was sent to gcc-patches first.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This renames all the remaining members of buildsym_compunit to start
with "m_" to follow the general naming convention.
gdb/ChangeLog
2018-07-20 Keith Seitz <keiths@redhat.com>
* buildsym.h (struct buildsym_compunit) <m_objfile, m_subfiles,
m_main_subfile, m_comp_dir, m_producer, m_debugformat,
m_compunit_symtab, m_language>: Add "m_" prefix.
Update all uses.
* buildsym.c: Update all uses.
The record_line_ftype typedef was only used in the DWARF reader, and
we removed those uses a few patches ago. So, remove the typedef.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* buildsym-legacy.h (record_line): Don't use record_line_ftype.
* buildsym.h (record_line_ftype): Remove typedef.
This introduces a new header, buildsym-legacy.h, and changes all the
symbol readers to use it. The idea is to put the function-based
interface, that relies on the buildsym_compunit global, into a
separate header. Then when a symbol reader is updated to use the new
interface, it can simply not include buildsym-legacy.h, so it's easy
to be sure that the new API is used everywhere.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* xcoffread.c: Include buildsym-legacy.h.
* windows-nat.c: Include buildsym-legacy.h.
* stabsread.c: Include buildsym-legacy.h.
* mdebugread.c: Include buildsym-legacy.h.
* buildsym-legacy.h: New file.
* buildsym-legacy.c: New file, from buildsym.c.
* go32-nat.c: Include buildsym-legacy.h.
* dwarf2read.c: Include buildsym-legacy.h.
* dbxread.c: Include buildsym-legacy.h.
* cp-namespace.c: Include buildsym-legacy.h.
* coffread.c: Include buildsym-legacy.h.
* buildsym.h: Move some contents to buildsym-legacy.h.
* buildsym.c: Include buildsym-legacy.h. Move many functions to
buildsym-legacy.c.
* Makefile.in (HFILES_NO_SRCDIR): Add buildsym-legacy.h.
This moves struct buildsym_compunit to buildsym.h. Now that the
members are private, and it no longer affects any global state in
buildsym.c, an instance can be used directly for symtab creation.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* buildsym.h (struct buildsym_compunit): Move from buildsym.c.
* buildsym.c (struct buildsym_compunit): Move to buildsym.h.
(buildsym_compunit::buildsym_compunit)
(buildsym_compunit::~buildsym_compunit)
(buildsym_compunit::get_macro_table): Define.
Nothing in buildsym.h relies on the "EXTERN" method of
declaration/definition, so remove the traces.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* buildsym.h (EXTERN): Don't define or undef.
* buildsym.c (EXTERN): Don't define.
This moves the pending_blocks and pending_block_obstack into
buildsym_compunit.
The obstack could perhaps be merged with the addrmap obstack, but I
did not do that in this series.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* buildsym.h (class scoped_free_pendings): Remove constructor.
* buildsym.c (struct buildsym_compunit) <free_pending_blocks>: New
method.
<m_pending_block_obstack, m_pending_blocks>: New members.
(pending_block_obstack, pending_blocks): Remove.
(scoped_free_pendings::scoped_free_pendings): Default.
(~scoped_free_pendings): Update.
(free_pending_blocks): Remove.
(finish_block_internal, record_pending_block, make_blockvector)
(end_symtab_get_static_block, augment_type_symtab, push_context)
(buildsym_init): Update.
This moves the context stack globals to be members of
buildsym_compunit, changing the type to a std::vector in the process.
Because the callers expect the context stack object to be valid after
being popped, at Simon's suggestion I've changed pop_context to return
the object rather than the pointer.
gdb/ChangeLog
2018-07-20 Tom Tromey <tom@tromey.com>
* coffread.c (coff_symtab_read): Update.
* xcoffread.c (read_xcoff_symtab): Update.
* dwarf2read.c (new_symbol): Update.
(read_func_scope, read_lexical_block_scope): Update.
* dbxread.c (process_one_symbol): Update.
* buildsym.h (context_stack, context_stack_depth): Don't declare.
(outermost_context_p): Remove macro.
(outermost_context_p, get_current_context_stack)
(get_context_stack_depth): Declare.
(pop_context): Return struct context_stack.
* buildsym.c (struct buildsym_compunit) <m_context_stack: New
member.
(context_stack_size): Remove.
(INITIAL_CONTEXT_STACK_SIZE): Remove.
(prepare_for_building, end_symtab_get_static_block)
(augment_type_symtab, push_context): Update.
(pop_context): Return struct context_stack.
(outermost_context_p, get_current_context_stack)
(get_context_stack_depth): New functions.
(buildsym_init): Update.
free_pending_blocks can be static because scoped_free_pendings (et al)
arrange for it to be NULL in the "steady state". This removes a
couple of unnecessary calls to free_pending_blocks and changes it to
be static.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* xcoffread.c (xcoff_initial_scan): Don't call
free_pending_blocks.
* dbxread.c (dbx_symfile_read): Don't call free_pending_blocks.
* buildsym.h (class scoped_free_pendings): Add constructor.
(free_pending_blocks): Don't declare.
* buildsym.c (scoped_free_pendings::scoped_free_pendings): New.
(free_pending_blocks): Now static.
This moves the global subfile_stack to be a member of
buildsym_compunit. It also change this to be a std::vector, which
simplifies the code.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* buildsym.h (push_subfile, pop_subfile): Update declarations.
* buildsym.c (struct buildsym_compunit) <m_subfile_stack>: New
member.
(struct subfile_stack): Remove.
(subfile_stack): Remove.
(push_subfile, pop_subfile, buildsym_init): Update.
I discovered that merge_symbol_lists is unused, so this removes it.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* buildsym.h (merge_symbol_lists): Remove.
* buildsym.c (merge_symbol_lists): Remove.
scan_file_globals is defined in stabsread.c, so move its declaration
to stabsread.h.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* stabsread.c (scan_file_globals): Update comment.
* stabsread.h (scan_file_globals): Move from buildsym.h.
* buildsym.h (scan_file_globals): Move to stabsread.h.
buildsym_new_init is just an alias for buildsym_init. This removes
it. In the long run buildsym_init will also go away; this patch just
helps make things a bit clearer in the meantime.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* xcoffread.c (xcoff_new_init): Update.
* mipsread.c (mipscoff_new_init): Update.
* mdebugread.c (mdebug_build_psymtabs): Update.
* elfread.c (elf_new_init): Update.
* dbxread.c (dbx_new_init, coffstab_build_psymtabs)
(elfstab_build_psymtabs, stabsect_build_psymtabs): Update.
* buildsym.h (buildsym_new_init): Don't declare.
* buildsym.c (buildsym_new_init): Remove.
The global within_function is only used by a few symbol readers. This
patch moves the global out of buildsym and into stabsread, which
seemed like a better fit. It also arranges for the existing readers
to clear the global at the appropriate time.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* stabsread.h (within_function): Move from buildsym.h.
* stabsread.c (start_stabs): Clear within_function.
* coffread.c (coff_start_symtab): Clear within_function.
* buildsym.h (within_function): Move to stabsread.h.
* buildsym.c (prepare_for_building): Update.
processing_gcc is also only used by stabsread -- it is set by the
DWARF reader, but this turns out not to be needed. So, this patch
moves processing_gcc and removes the assignment from the DWARF reader.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* stabsread.h (processing_gcc_compilation): Move from buildsym.h.
* dwarf2read.c (dwarf2_start_symtab): Don't set
processing_gcc_compilation.
* buildsym.h (processing_gcc_compilation): Move to stabsread.h.
A few things that currently reside in buildsym.c turn out to be
specific to the stabs reader. This patch moves these from
buildsym.[ch] to stabsread.[ch].
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* stabsread.h (HASHSIZE, hashname, symnum, next_symbol_text)
(next_symbol_text_func): Move from buildsym.h.
* stabsread.c (hashname): Move from buildsym.c.
* buildsym.h (HASHSIZE, symnum, next_symbol_text)
(next_symbol_text_func, hashname): Move to stabsread.h.
* buildsym.c: Don't include bcache.h
(hashname): Move to stasbread.c.
context_stack_size is declared in buildsym.h, but only used in
buildsym.c. This makes it static in buildsym.c.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* buildsym.h (context_stack_size): Don't declare.
* buildsym.c (context_stack_size): New global.
processing_acc_compilation is only used in dbxread.c, so move it
there.
gdb/ChangeLog
2018-07-16 Tom Tromey <tom@tromey.com>
* dbxread.c (processing_acc_compilation): New global.
* buildsym.h (processing_acc_compilation): Don't declare.
Currently, we have a mess of symbol name hashing/comparison routines.
There's msymbol_hash for mangled names, and dict_hash and
msymbol_hash_iw for demangled names. Then there's strcmp_iw,
strcmp_iw_ordered and Ada's full_match/wild_match, which all have to
agree with the hashing routines. That's why dict_hash is really about
Ada names. From the inconsistency department, minimal symbol hashing
doesn't go via dict_hash, so Ada's wild matching can't ever work with
minimal symbols.
This patch starts fixing this, by doing two things:
#1 - adds a language vector method to let each language decide how to
compute a symbol name hash.
#2 - makes dictionaries know the language of the symbols they hold,
and then use the dictionaries language to decide which hashing
method to use.
For now, this is just scaffolding, since all languages install the
default method. The series will make C++ install its own hashing
method later on, and will add per-language symbol name comparison
routines too.
This patch was originally based on a patch that Keith wrote for the
libcc1/C++ WIP support.
gdb/ChangeLog:
2017-11-08 Keith Seitz <keiths@redhat.com>
Pedro Alves <palves@redhat.com>
* ada-lang.c (ada_language_defn): Install
default_search_name_hash.
* buildsym.c (struct buildsym_compunit): <language>: New field.
(finish_block_internal): Pass language when creating dictionaries.
(start_buildsym_compunit, start_symtab): New language parameters.
Use them.
(restart_symtab): Pass down compilation unit's language.
* buildsym.h (enum language): Forward declare.
(start_symtab): New 'language' parameter.
* c-lang.c (c_language_defn, cplus_language_defn)
(asm_language_defn, minimal_language_defn): Install
default_search_name_hash.
* coffread.c (coff_start_symtab): Adjust.
* d-lang.c (d_language_defn): Install default_search_name_hash.
* dbxread.c (struct symloc): Add 'pst_language' field.
(PST_LANGUAGE): Define.
(start_psymtab, read_ofile_symtab): Use it.
(process_one_symbol): New 'language' parameter. Pass it down.
* dictionary.c (struct dictionary) <language>: New field.
(DICT_LANGUAGE): Define.
(dict_create_hashed, dict_create_hashed_expandable)
(dict_create_linear, dict_create_linear_expandable): New parameter
'language'. Set the dictionary's language.
(iter_match_first_hashed): Adjust to rename.
(insert_symbol_hashed): Assert we don't see mismatching
languages. Adjust to rename.
(dict_hash): Rename to ...
(default_search_name_hash): ... this and make extern.
* dictionary.h (struct language_defn): Forward declare.
(dict_create_hashed): New parameter 'language'.
* dwarf2read.c (dwarf2_start_symtab): Pass down language.
* f-lang.c (f_language_defn): Install default_search_name_hash.
* go-lang.c (go_language_defn): Install default_search_name_hash.
* jit.c (finalize_symtab): Pass compunit's language to dictionary
creation.
* language.c (unknown_language_defn, auto_language_defn):
* language.h (language_defn::la_search_name_hash): New field.
(default_search_name_hash): Declare.
* m2-lang.c (m2_language_defn): Install default_search_name_hash.
* mdebugread.c (new_block): New parameter 'language'.
* mdebugread.c (parse_symbol): Pass symbol language to block
allocation.
(psymtab_to_symtab_1): Pass down language.
(new_symtab): Pass compunit's language to block allocation.
* objc-lang.c (objc_language_defn): Install
default_search_name_hash.
* opencl-lang.c (opencl_language_defn):
* p-lang.c (pascal_language_defn): Install
default_search_name_hash.
* rust-lang.c (rust_language_defn): Install
default_search_name_hash.
* stabsread.h (enum language): Forward declare.
(process_one_symbol): Add 'language' parameter.
* symtab.c (search_name_hash): New function.
* symtab.h (search_name_hash): Declare.
* xcoffread.c (read_xcoff_symtab): Pass language to start_symtab.
This introduces scoped_free_pendings, and changes users of
really_free_pendings to use it instead, removing some clenaups.
I tried to examine the affected code to ensure there aren't dangling
cleanups in the vicinity.
gdb/ChangeLog
2017-11-04 Tom Tromey <tom@tromey.com>
* dwarf2read.c (process_full_comp_unit, process_full_type_unit):
Use scoped_free_pendings.
* dbxread.c (dbx_symfile_read, dbx_psymtab_to_symtab_1): Use
scoped_free_pendings.
* xcoffread.c (xcoff_psymtab_to_symtab_1): Use scoped_free_pendings.
(xcoff_initial_scan): Likewise.
* buildsym.c (reset_symtab_globals): Update comment.
(scoped_free_pendings): Rename from really_free_pendings.
(prepare_for_building): Update comment.
(buildsym_init): Likewise.
* buildsym.h (class scoped_free_pendings): New class.
(really_free_pendings): Don't declare.
This applies the second part of GDB's End of Year Procedure, which
updates the copyright year range in all of GDB's files.
gdb/ChangeLog:
Update copyright year range in all GDB files.
GDB's current behavior when dealing with non-local references in the
context of nested fuctions is approximative:
- code using valops.c:value_of_variable read the first available stack
frame that holds the corresponding variable (whereas there can be
multiple candidates for this);
- code directly relying on read_var_value will instead read non-local
variables in frames where they are not even defined.
This change adds the necessary context to symbol reads (to get the block
they belong to) and to blocks (the static link property, if any) so that
GDB can make the proper decisions when dealing with non-local varibale
references.
gdb/ChangeLog:
* ada-lang.c (ada_read_var_value): Add a var_block argument
and pass it to default_read_var_value.
* block.c (block_static_link): New accessor.
* block.h (block_static_link): Declare it.
* buildsym.c (finish_block_internal): Add a static_link
argument. If there is a static link, associate it to the new
block.
(finish_block): Add a static link argument and pass it to
finish_block_internal.
(end_symtab_get_static_block): Update calls to finish_block and
to finish_block_internal.
(end_symtab_with_blockvector): Update call to
finish_block_internal.
* buildsym.h: Forward-declare struct dynamic_prop.
(struct context_stack): Add a static_link field.
(finish_block): Add a static link argument.
* c-exp.y: Remove an obsolete comment (evaluation of variables
already start from the selected frame, and now they climb *up*
the call stack) and propagate the block information to the
produced expression.
* d-exp.y: Likewise.
* f-exp.y: Likewise.
* go-exp.y: Likewise.
* jv-exp.y: Likewise.
* m2-exp.y: Likewise.
* p-exp.y: Likewise.
* coffread.c (coff_symtab_read): Update calls to finish_block.
* dbxread.c (process_one_symbol): Likewise.
* xcoffread.c (read_xcoff_symtab): Likewise.
* compile/compile-c-symbols.c (convert_one_symbol): Promote the
"sym" parameter to struct block_symbol, update its uses and pass
its block to calls to read_var_value.
(convert_symbol_sym): Update the calls to convert_one_symbol.
* compile/compile-loc2c.c (do_compile_dwarf_expr_to_c): Update
call to read_var_value.
* dwarf2loc.c (block_op_get_frame_base): New.
(dwarf2_block_frame_base_locexpr_funcs): Implement the
get_frame_base method.
(dwarf2_block_frame_base_loclist_funcs): Likewise.
(dwarf2locexpr_baton_eval): Add a frame argument and use it
instead of the selected frame in order to evaluate the
expression.
(dwarf2_evaluate_property): Add a frame argument. Update call
to dwarf2_locexpr_baton_eval to provide a frame in available and
to handle the absence of address stack.
* dwarf2loc.h (dwarf2_evaluate_property): Add a frame argument.
* dwarf2read.c (attr_to_dynamic_prop): Add a forward
declaration.
(read_func_scope): Record any available static link description.
Update call to finish_block.
(read_lexical_block_scope): Update call to finish_block.
* findvar.c (follow_static_link): New.
(get_hosting_frame): New.
(default_read_var_value): Add a var_block argument. Use
get_hosting_frame to handle non-local references.
(read_var_value): Add a var_block argument and pass it to the
LA_READ_VAR_VALUE method.
* gdbtypes.c (resolve_dynamic_range): Update calls to
dwarf2_evaluate_property.
(resolve_dynamic_type_internal): Likewise.
* guile/scm-frame.c (gdbscm_frame_read_var): Update call to
read_var_value, passing it the block coming from symbol lookup.
* guile/scm-symbol.c (gdbscm_symbol_value): Update call to
read_var_value (TODO).
* infcmd.c (finish_command_continuation): Update call to
read_var_value, passing it the block coming from symbol lookup.
* infrun.c (insert_exception_resume_breakpoint): Likewise.
* language.h (struct language_defn): Add a var_block argument to
the LA_READ_VAR_VALUE method.
* objfiles.c (struct static_link_htab_entry): New.
(static_link_htab_entry_hash): New.
(static_link_htab_entry_eq): New.
(objfile_register_static_link): New.
(objfile_lookup_static_link): New.
(free_objfile): Free the STATIC_LINKS hashed map if needed.
* objfiles.h: Include hashtab.h.
(struct objfile): Add a static_links field.
(objfile_register_static_link): New.
(objfile_lookup_static_link): New.
* printcmd.c (print_variable_and_value): Update call to
read_var_value.
* python/py-finishbreakpoint.c (bpfinishpy_init): Likewise.
* python/py-frame.c (frapy_read_var): Update call to
read_var_value, passing it the block coming from symbol lookup.
* python/py-framefilter.c (extract_sym): Add a sym_block
parameter and set the pointed value to NULL (TODO).
(enumerate_args): Update call to extract_sym.
(enumerate_locals): Update calls to extract_sym and to
read_var_value.
* python/py-symbol.c (sympy_value): Update call to
read_var_value (TODO).
* stack.c (read_frame_local): Update call to read_var_value.
(read_frame_arg): Likewise.
(return_command): Likewise.
* symtab.h (struct symbol_block_ops): Add a get_frame_base
method.
(struct symbol): Add a block field.
(SYMBOL_BLOCK): New accessor.
* valops.c (value_of_variable): Remove frame/block handling and
pass the block argument to read_var_value, which does this job
now.
(value_struct_elt_for_reference): Update calls to
read_var_value.
(value_of_this): Pass the block found to read_var_value.
* value.h (read_var_value): Add a var_block argument.
(default_read_var_value): Likewise.
gdb/testsuite/ChangeLog:
* gdb.base/nested-subp1.exp: New file.
* gdb.base/nested-subp1.c: New file.
* gdb.base/nested-subp2.exp: New file.
* gdb.base/nested-subp2.c: New file.
* gdb.base/nested-subp3.exp: New file.
* gdb.base/nested-subp3.c: New file.
Consider the following declaration:
function Foo (I : Integer) return Integer renames Pack.Bar;
As Foo is not materialized as a routine whose name is derived from Foo,
GDB currently cannot use it:
(gdb) print foo(0)
No definition of "foo" in current context.
However, compilers can emit DW_TAG_imported_declaration in order to
materialize the fact that Foo is actually another name for Pack.Bar.
This commit enhances the DWARF reader to record global renamings (it
used to put global ones in a static block) and enhances the Ada engine
to leverage this information during symbol lookup.
gdb/ChangeLog:
* ada-lang.c: Include namespace.h
(aux_add_nonlocal_symbols): Fix a function name in comment.
(ada_add_block_renamings): New.
(add_nonlocal_symbols): Add global renamings handling.
(ada_lookup_symbol_list_worker): Move the symbol lookup part
to...
(ada_add_all_symbols): ... this new function.
(ada_add_block_symbols): Try to match the input name against the
"using directives list", perform a recursive symbol lookup on
the matched declarations.
* block.h (struct block): Move the_namespace to top-level as
namespace_info. Remove the language_specific field.
(BLOCK_NAMESPACE): Update access to the namespace_info field.
* buildsym.h (using_directives): Rename into...
(local_using_directives): ... this.
(global_using_directives): New.
(struct context_stack): Rename the using_directives field into
local_using_directives.
* buildsym.c (finish_block_internal): Deal with the proper
using directives repository (local or global).
(prepare_for_building): Reset local_using_directives. Assert
that there is no pending global using directive.
(reset_symtab_globals): Reset global_using_directives and
local_using_directives.
(end_symtab_get_static_block): Don't ignore symtabs that have
only using directives.
(push_context): Update references to local_using_directives.
(buildsym_init): Do not reset using_directives.
* cp-support.c: Include namespace.h.
* cp-support.h (struct using_direct): Move to namespace.h.
(cp_add_using_directives): Move to namespace.h.
* cp-namespace.c: Include namespace.h
(cp_add_using_directive): Move to namespace.c, rename it to
add_using_directive, add a "using_directives" argument and use
it as the pending using directives repository. All callers
updated.
* dwarf2read.c (using_directives): New.
(read_import_statement): Call using_directives.
(read_func_scope): Update references to local_using_directives.
(read_lexical_block_scope): Likewise.
(read_namespace): Update the heading comment, call
using_directives.
* namespace.h: New file.
* namespace.c: New file.
* Makefile.in (SFILES): Add namespace.c.
(COMMON_OBS): Add namespace.o
gdb/testsuite/ChangeLog:
* gdb.ada/fun_renaming.exp: New testcase.
* gdb.ada/fun_renaming/fun_renaming.adb: New file.
* gdb.ada/fun_renaming/pack.adb: New file.
* gdb.ada/fun_renaming/pack.ads: New file.
Tested on x86_64-linux. Support for this in GCC is in the pipeline: see
<https://gcc.gnu.org/ml/gcc-patches/2015-07/msg02166.html>.
gdb/ChangeLog:
* buildsym.c: Add comments describing how the buildsym machinery
is used by the various file formats.
(really_free_pendings): Enhance function comment.
See pending_macros to NULL. Simplify resetting pending_addrmap.
Call free_buildsym_compunit.
(free_buildsym_compunit): Set current_subfile to NULL.
(prepare_for_building): New function.
(start_symtab): Call it. Remove call to set_last_source_file.
(restart_symtab): New arg "cust". All callers updated.
Simplify, call prepare_for_building. Re-initialize buildsym_compunit.
(reset_symtab_globals): Enhance function comment.
Set local_symbols, file_symbols, global_symbols to NULL.
Set pending_macros to NULL. Simplify resetting pending_addrmap.
Call free_buildysym_compunit.
(end_symtab_without_blockvector): Delete. All callers updated.
(end_symtab_with_blockvector): Remove redundant call to
free_buildsym_compunit.
(augment_type_symtab): Remove arg "cust". All callers updated.
(buildsym_init): Remove resetting of free_pendings, file_symbols,
global_symbols, pending_blocks, pending_macros. Instead make
handling consistent with pending_addrmap: Assert value was reset
at end of previous symtab building. Initialize context_stack here.
Currently "symtabs" in gdb are stored as a single linked list of
struct symtab that contains both symbol symtabs (the blockvectors)
and file symtabs (the linetables).
This has led to confusion, bugs, and performance issues.
This patch is conceptually very simple: split struct symtab into
two pieces: one part containing things common across the entire
compilation unit, and one part containing things specific to each
source file.
Example.
For the case of a program built out of these files:
foo.c
foo1.h
foo2.h
bar.c
foo1.h
bar.h
Today we have a single list of struct symtabs:
objfile -> foo.c -> foo1.h -> foo2.h -> bar.c -> foo1.h -> bar.h -> NULL
where "->" means the "next" pointer in struct symtab.
With this patch, that turns into:
objfile -> foo.c(cu) -> bar.c(cu) -> NULL
| |
v v
foo.c bar.c
| |
v v
foo1.h foo1.h
| |
v v
foo2.h bar.h
| |
v v
NULL NULL
where "foo.c(cu)" and "bar.c(cu)" are struct compunit_symtab objects,
and the files foo.c, etc. are struct symtab objects.
So now, for example, when we want to iterate over all blockvectors
we can now just iterate over the compunit_symtab list.
Plus a lot of the data that was either unused or replicated for each
symtab in a compilation unit now lives in struct compunit_symtab.
E.g., the objfile pointer, the producer string, etc.
I thought of moving "language" out of struct symtab but there is
logic to try to compute the language based on previously seen files,
and I think that's best left as is for now.
With my standard monster benchmark with -readnow (which I can't actually
do, but based on my calculations), whereas today the list requires
77MB to store all the struct symtabs, it now only requires 37MB.
A modest space savings given the gigabytes needed for all the debug info,
etc. Still, it's nice. Plus, whereas today we create a copy of dirname
for each source file symtab in a compilation unit, we now only create one
for the compunit.
So this patch is basically just a data structure reorg,
I don't expect significant performance improvements from it.
Notes:
1) A followup patch can do a similar split for struct partial_symtab.
I have left that until after I get the changes I want in to
better utilize .gdb_index (it may affect how we do partial syms).
2) Another followup patch *could* rename struct symtab.
The term "symtab" is ambiguous and has been a source of confusion.
In this patch I'm leaving it alone, calling it the "historical" name
of "filetabs", which is what they are now: just the file-name + line-table.
gdb/ChangeLog:
Split struct symtab into two: struct symtab and compunit_symtab.
* amd64-tdep.c (amd64_skip_xmm_prologue): Fetch producer from compunit.
* block.c (blockvector_for_pc_sect): Change "struct symtab *" argument
to "struct compunit_symtab *". All callers updated.
(set_block_compunit_symtab): Renamed from set_block_symtab. Change
"struct symtab *" argument to "struct compunit_symtab *".
All callers updated.
(get_block_compunit_symtab): Renamed from get_block_symtab. Change
result to "struct compunit_symtab *". All callers updated.
(find_iterator_compunit_symtab): Renamed from find_iterator_symtab.
Change result to "struct compunit_symtab *". All callers updated.
* block.h (struct global_block) <compunit_symtab>: Renamed from symtab.
hange type to "struct compunit_symtab *". All uses updated.
(struct block_iterator) <d.compunit_symtab>: Renamed from "d.symtab".
Change type to "struct compunit_symtab *". All uses updated.
* buildsym.c (struct buildsym_compunit): New struct.
(subfiles, buildsym_compdir, buildsym_objfile, main_subfile): Delete.
(buildsym_compunit): New static global.
(finish_block_internal): Update to fetch objfile from
buildsym_compunit.
(make_blockvector): Delete objfile argument.
(start_subfile): Rewrite to use buildsym_compunit. Don't initialize
debugformat, producer.
(start_buildsym_compunit): New function.
(free_buildsym_compunit): Renamed from free_subfiles_list.
All callers updated.
(patch_subfile_names): Rewrite to use buildsym_compunit.
(get_compunit_symtab): New function.
(get_macro_table): Delete argument comp_dir. All callers updated.
(start_symtab): Change result to "struct compunit_symtab *".
All callers updated. Create the subfile of the main source file.
(watch_main_source_file_lossage): Rewrite to use buildsym_compunit.
(reset_symtab_globals): Update.
(end_symtab_get_static_block): Update to use buildsym_compunit.
(end_symtab_without_blockvector): Rewrite.
(end_symtab_with_blockvector): Change result to
"struct compunit_symtab *". All callers updated.
Update to use buildsym_compunit. Don't set symtab->dirname,
instead set it in the compunit.
Explicitly make sure main symtab is first in its list.
Set debugformat, producer, blockvector, block_line_section, and
macrotable in the compunit.
(end_symtab_from_static_block): Change result to
"struct compunit_symtab *". All callers updated.
(end_symtab, end_expandable_symtab): Ditto.
(set_missing_symtab): Change symtab argument to
"struct compunit_symtab *". All callers updated.
(augment_type_symtab): Ditto.
(record_debugformat): Update to use buildsym_compunit.
(record_producer): Update to use buildsym_compunit.
* buildsym.h (struct subfile) <dirname>: Delete.
<producer, debugformat>: Delete.
<buildsym_compunit>: New member.
(get_compunit_symtab): Declare.
* dwarf2read.c (struct type_unit_group) <compunit_symtab>: Renamed
from primary_symtab. Change type to "struct compunit_symtab *".
All uses updated.
(dwarf2_start_symtab): Change result to "struct compunit_symtab *".
All callers updated.
(dwarf_decode_macros): Delete comp_dir argument. All callers updated.
(struct dwarf2_per_cu_quick_data) <compunit_symtab>: Renamed from
symtab. Change type to "struct compunit_symtab *". All uses updated.
(dw2_instantiate_symtab): Change result to "struct compunit_symtab *".
All callers updated.
(dw2_find_last_source_symtab): Ditto.
(dw2_lookup_symbol): Ditto.
(recursively_find_pc_sect_compunit_symtab): Renamed from
recursively_find_pc_sect_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(dw2_find_pc_sect_compunit_symtab): Renamed from
dw2_find_pc_sect_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(get_compunit_symtab): Renamed from get_symtab. Change result to
"struct compunit_symtab *". All callers updated.
(recursively_compute_inclusions): Change type of immediate_parent
argument to "struct compunit_symtab *". All callers updated.
(compute_compunit_symtab_includes): Renamed from
compute_symtab_includes. All callers updated. Rewrite to compute
includes of compunit_symtabs and not symtabs.
(process_full_comp_unit): Update to work with struct compunit_symtab.
(process_full_type_unit): Ditto.
(dwarf_decode_lines_1): Delete argument comp_dir. All callers updated.
(dwarf_decode_lines): Remove special case handling of main subfile.
(macro_start_file): Delete argument comp_dir. All callers updated.
(dwarf_decode_macro_bytes): Ditto.
* guile/scm-block.c (bkscm_print_block_syms_progress_smob): Update to
use struct compunit_symtab.
* i386-tdep.c (i386_skip_prologue): Fetch producer from compunit.
* jit.c (finalize_symtab): Build compunit_symtab.
* jv-lang.c (get_java_class_symtab): Change result to
"struct compunit_symtab *". All callers updated.
* macroscope.c (sal_macro_scope): Fetch macro table from compunit.
* macrotab.c (struct macro_table) <compunit_symtab>: Renamed from
comp_dir. Change type to "struct compunit_symtab *".
All uses updated.
(new_macro_table): Change comp_dir argument to cust,
"struct compunit_symtab *". All callers updated.
* maint.c (struct cmd_stats) <nr_compunit_symtabs>: Renamed from
nr_primary_symtabs. All uses updated.
(count_symtabs_and_blocks): Update to handle compunits.
(report_command_stats): Update output, "primary symtabs" renamed to
"compunits".
* mdebugread.c (new_symtab): Change result to
"struct compunit_symtab *". All callers updated.
(parse_procedure): Change type of search_symtab argument to
"struct compunit_symtab *". All callers updated.
* objfiles.c (objfile_relocate1): Loop over blockvectors in a
separate loop.
* objfiles.h (struct objfile) <compunit_symtabs>: Renamed from
symtabs. Change type to "struct compunit_symtab *". All uses updated.
(ALL_OBJFILE_FILETABS): Renamed from ALL_OBJFILE_SYMTABS.
All uses updated.
(ALL_OBJFILE_COMPUNITS): Renamed from ALL_OBJFILE_PRIMARY_SYMTABS.
All uses updated.
(ALL_FILETABS): Renamed from ALL_SYMTABS. All uses updated.
(ALL_COMPUNITS): Renamed from ALL_PRIMARY_SYMTABS. All uses updated.
* psympriv.h (struct partial_symtab) <compunit_symtab>: Renamed from
symtab. Change type to "struct compunit_symtab *". All uses updated.
* psymtab.c (psymtab_to_symtab): Change result type to
"struct compunit_symtab *". All callers updated.
(find_pc_sect_compunit_symtab_from_partial): Renamed from
find_pc_sect_symtab_from_partial. Change result type to
"struct compunit_symtab *". All callers updated.
(lookup_symbol_aux_psymtabs): Change result type to
"struct compunit_symtab *". All callers updated.
(find_last_source_symtab_from_partial): Ditto.
* python/py-symtab.c (stpy_get_producer): Fetch producer from compunit.
* source.c (forget_cached_source_info_for_objfile): Fetch debugformat
and macro_table from compunit.
* symfile-debug.c (debug_qf_find_last_source_symtab): Change result
type to "struct compunit_symtab *". All callers updated.
(debug_qf_lookup_symbol): Ditto.
(debug_qf_find_pc_sect_compunit_symtab): Renamed from
debug_qf_find_pc_sect_symtab, change result type to
"struct compunit_symtab *". All callers updated.
* symfile.c (allocate_symtab): Delete objfile argument.
New argument cust.
(allocate_compunit_symtab): New function.
(add_compunit_symtab_to_objfile): New function.
* symfile.h (struct quick_symbol_functions) <lookup_symbol>:
Change result type to "struct compunit_symtab *". All uses updated.
<find_pc_sect_compunit_symtab>: Renamed from find_pc_sect_symtab.
Change result type to "struct compunit_symtab *". All uses updated.
* symmisc.c (print_objfile_statistics): Compute blockvector count in
separate loop.
(dump_symtab_1): Update test for primary source symtab.
(maintenance_info_symtabs): Update to handle compunit symtabs.
(maintenance_check_symtabs): Ditto.
* symtab.c (set_primary_symtab): Delete.
(compunit_primary_filetab): New function.
(compunit_language): New function.
(iterate_over_some_symtabs): Change type of arguments "first",
"after_last" to "struct compunit_symtab *". All callers updated.
Update to loop over symtabs in each compunit.
(error_in_psymtab_expansion): Rename symtab argument to cust,
and change type to "struct compunit_symtab *". All callers updated.
(find_pc_sect_compunit_symtab): Renamed from find_pc_sect_symtab.
Change result type to "struct compunit_symtab *". All callers updated.
(find_pc_compunit_symtab): Renamed from find_pc_symtab.
Change result type to "struct compunit_symtab *". All callers updated.
(find_pc_sect_line): Only loop over symtabs within selected compunit
instead of all symtabs in the objfile.
* symtab.h (struct symtab) <blockvector>: Moved to compunit_symtab.
<compunit_symtab> New member.
<block_line_section>: Moved to compunit_symtab.
<locations_valid>: Ditto.
<epilogue_unwind_valid>: Ditto.
<macro_table>: Ditto.
<dirname>: Ditto.
<debugformat>: Ditto.
<producer>: Ditto.
<objfile>: Ditto.
<call_site_htab>: Ditto.
<includes>: Ditto.
<user>: Ditto.
<primary>: Delete
(SYMTAB_COMPUNIT): New macro.
(SYMTAB_BLOCKVECTOR): Update definition.
(SYMTAB_OBJFILE): Update definition.
(SYMTAB_DIRNAME): Update definition.
(struct compunit_symtab): New type. Common members among all source
symtabs within a compilation unit moved here. All uses updated.
(COMPUNIT_OBJFILE): New macro.
(COMPUNIT_FILETABS): New macro.
(COMPUNIT_DEBUGFORMAT): New macro.
(COMPUNIT_PRODUCER): New macro.
(COMPUNIT_DIRNAME): New macro.
(COMPUNIT_BLOCKVECTOR): New macro.
(COMPUNIT_BLOCK_LINE_SECTION): New macro.
(COMPUNIT_LOCATIONS_VALID): New macro.
(COMPUNIT_EPILOGUE_UNWIND_VALID): New macro.
(COMPUNIT_CALL_SITE_HTAB): New macro.
(COMPUNIT_MACRO_TABLE): New macro.
(ALL_COMPUNIT_FILETABS): New macro.
(compunit_symtab_ptr): New typedef.
(DEF_VEC_P (compunit_symtab_ptr)): New vector type.
gdb/testsuite/ChangeLog:
* gdb.base/maint.exp: Update expected output.
gdb/ChangeLog:
* buildsym.h (record_line_ftype): New typedef.
(record_line): Use it.
* dwarf2read.c (dwarf_record_line, dwarf_finish_line): New functions.
(dwarf_decode_lines_1): Call them.
(pending_macros): Ditto.
(get_macro_table): New function.
(buildsym_init): Initialize subfile_stack.
* coffread.c (type_vector,type_vector_length): Moved here from
buildsym.h.
(INITIAL_TYPE_VECTOR_LENGTH): Ditto.
(coff_symtab_read): Use it.
* dbxread.c (read_ofile_symtab): Delete init of subfile_stack.
* dwarf2read.c (macro_start_file): Replace uses of pending_macros
with call to get_macro_table.
* stabsread.c (type_vector,type_vector_length): Moved here from
buildsym.h.
(INITIAL_TYPE_VECTOR_LENGTH): Ditto.
* buildsym.h (get_macro_table): Declare.
(start_symtab): Make 'name' and 'dirname' const. Use
set_last_source_file.
(restart_symtab, reset_symtab_globals): Use set_last_source_file.
(last_source_file): Define. Now static.
(set_last_source_file, get_last_source_file): New functions.
* buildsym.h (last_source_file): Don't declare.
(start_symtab): Update.
(set_last_source_file, get_last_source_file): Declare.
* coffread.c (complete_symtab): Use set_last_source_file.
(coff_end_symtab): Likewise.
(coff_symtab_read): Use set_last_source_file, get_last_source_file.
* dbxread.c (read_dbx_symtab, read_ofile_symtab): Use
set_last_source_file.
(process_one_symbol): Use get_last_source_file.
* mdebugread.c (parse_partial_symbols): Use set_last_source_file.
(psymtab_to_symtab_1): Use get_last_source_file.
* xcoffread.c (process_linenos): Use get_last_source_file.
(complete_symtab): Use set_last_source_file.
(read_xcoff_symtab): Use set_last_source_file, get_last_source_file.
(scan_xcoff_symtab): Use set_last_source_file.
Two modifications:
1. The addition of 2013 to the copyright year range for every file;
2. The use of a single year range, instead of potentially multiple
year ranges, as approved by the FSF.
* buildsym.c (end_symtab_1): Split it to ...
(end_symtab_get_static_block): ... this ...
(end_symtab_from_static_block): ... and this function.
(end_symtab, end_expandable_symtab): Call them.
* buildsym.h (end_symtab_get_static_block)
(end_symtab_from_static_block): New declarations.
* dwarf2read.c (process_full_comp_unit): New variable static_block.
Set its valid CU ranges.
gdb/testsuite/
* gdb.dwarf2/dw2-minsym-in-cu.S: New file.
* gdb.dwarf2/dw2-minsym-in-cu.exp: New file.
All callers updated.
(start_symtab): Move most contents to ...
(restart_symtab): ... here. New function.
(reset_symtab_globals): New function.
(end_symtab_1): Renamed from end_symtab. New arg "expandable".
Call reset_symtab_globals.
(end_symtab, end_expandable_symtab): New functions.
(set_missing_symtab, augment_type_symtab): New functions.
* buildsym.h (end_expandable_symtab): Declare.
(augment_type_symtab, restart_symtab): Declare.
Andrew Burgess
Joel Brobecker
Tom Tromey
Keith Seitz
Pedro Alves
Pierre-Marie de Rodat
Doug Evans
Doug Evans
Tom Tromey
Joel Brobecker
Jan Kratochvil