search for: pubtyp

...defaults based on the target platform. Other bits aren't but probably ought to be. Some of these are little things: - various Apple-defined attributes (DW_AT_APPLE_*) - TLS opcode (DW_OP_form_tls_address v. DW_OP_GNU_push_tls_address) Some are bigger things: - accelerator tables - pubnames/pubtypes Really these aren't so much _platform_ specific things as they are _debugger_ specific things. For example: - accelerator tables: default on for Darwin, but really on for LLDB. - pubnames/pubtypes: off for Darwin and PS4, but really on for GDB. We're co-opting platform as a proxy for th...

Hello all, I am implementing support for .debug_names section (which is introduced in DWARFv5 standard as replacement for .debug_pubnames and .debug_pubtypes). The question is: should usage of DWARF version 5 force generation of .debug_names instead of .debug_pubnames or we can make it just default behavior and provide user with the interface (cmd switch) to use other DWARFv5 features but generate old .debug_pubnames and .debug_pubtypes? The thing...

..._today_ in a way that's easier to talk about and do something about than the target-oriented mish-mash we have now. It's a whole lot simpler to say something like "FreeBSD implies LLDB" instead of "FreeBSD implies accelerator tables and standard TLS opcode and no pubnames or pubtypes." Or would you rather say "--lang-feature=auto --lang-feature=rvalue-ref --lang-feature=move_ctor ..." than "-std=c++11"? > IE a year from now, somebody comes along with a version of GDB that > doesn't match what your current "tuning profile" is, an...

Bunch of initially unrelated context: * type units can be referenced in a variety of ways: * DW_FORM_ref_sig8 on any attribute needing to reference the type * DW_AT_signature on a declaration of the type * extra wrinkle: the declaration can be nested into the appropriate namespace and given a name, or not * LLVM always does the "most expressive"/expensive thing: a full

Hi All, Some of you may have noticed a commit that added something called "Dwarf Accelerator Tables". The commit had a few of the salient points, but I thought I'd elaborate here and talk about what's going on with that. Basically we've got the pubnames and pubtypes sections in dwarf that aren't particularly useful for debuggers. The code I just committed adds some new tables that allow better indexing for debuggers. LLDB is already equipped to deal with these tables in current ToT. Going forward I'll be committing a few patches to fix issues as the...

...ete debug info which refers to code deleted by the linker     doing the garbage collection (gc-sections).   - Deduplicate debug type definitions for reducing resulting size of binary.   - Build accelerator/index tables.     = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, .debug_pubtypes.   - Strip unneeded tables.     = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, .debug_pubtypes.   - Compress or decompress debug info as requested. Possible feature:   - Join split dwarf .dwo files in a single file containing all debug info     (convert split DWARF into mo...

...   doing the garbage collection (gc-sections). > >    - Deduplicate debug type definitions for reducing resulting > size of > binary. > >    - Build accelerator/index tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Strip unneeded tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Compress or decompress debug info as requested. > > Possible feature: > >    - Join split dwarf .dwo files in a si...

..."no tuning" option, in favor of the historical GDB default, because in fact it wasn't really clear what "no tuning" should mean. The best answer I can come up with is: Emit all standard things that we know how to emit, and no non-standard things. This would mean: pubnames/pubtypes, aranges, no accelerator tables, standard TLS opcode. Possibly type units, although that's currently not a tuning thing, and support for it isn't particularly widespread. > If LLVM doesn't do target-specific defaulting, then Clang would have to. Since you are calling out “no acce...

...   doing the garbage collection (gc-sections). > >    - Deduplicate debug type definitions for reducing resulting > size of > binary. > >    - Build accelerator/index tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Strip unneeded tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Compress or decompress debug info as requested. > > Possible feature: > >    - Join split dwarf .dwo files in a si...

...   - Deduplicate debug type definitions for reducing >> resulting size of >> binary. >> >>    - Build accelerator/index tables. >>      = .debug_aranges, .debug_names, .gdb_index, >> .debug_pubnames, >> .debug_pubtypes. >> >>    - Strip unneeded tables. >>      = .debug_aranges, .debug_names, .gdb_index, >> .debug_pubnames, >> .debug_pubtypes. >> >>    - Compress or decompress debug info as requested. >> >> Pos...

Another example would be .debug_pubnames and .debug_pubtypes sections. Currently these default to omitted for Darwin and PS4, but included everywhere else. My initial patch for "tuning" changes the PS4 platform criterion to the SCE debugger predicate; quite likely the "not Darwin" criterion ought to be "not LLDB" or in other w...

...>>> resulting size of >>> binary. >>> >>>    - Build accelerator/index tables. >>>      = .debug_aranges, .debug_names, .gdb_index, >>> .debug_pubnames, >>> .debug_pubtypes. >>> >>>    - Strip unneeded tables. >>>      = .debug_aranges, .debug_names, .gdb_index, >>> .debug_pubnames, >>> .debug_pubtypes. >>> >>>    - Compress or decompress debug...

..."no tuning" option, in favor of the historical GDB default, because in fact it wasn't really clear what "no tuning" should mean. The best answer I can come up with is: Emit all standard things that we know how to emit, and no non-standard things. This would mean: pubnames/pubtypes, aranges, no accelerator tables, standard TLS opcode. Possibly type units, although that's currently not a tuning thing, and support for it isn't particularly widespread. If LLVM doesn't do target-specific defaulting, then Clang would have to. Second: The GNU TLS opcode thing is rea...

...>>>> binary. >>>> >>>>    - Build accelerator/index tables. >>>>      = .debug_aranges, .debug_names, .gdb_index, >>>> .debug_pubnames, >>>> .debug_pubtypes. >>>> >>>>    - Strip unneeded tables. >>>>      = .debug_aranges, .debug_names, .gdb_index, >>>> .debug_pubnames, >>>> .debug_pubtypes. >>>> >>>>...

...   doing the garbage collection (gc-sections). > >    - Deduplicate debug type definitions for reducing resulting > size of > binary. > >    - Build accelerator/index tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Strip unneeded tables. >      = .debug_aranges, .debug_names, .gdb_index, .debug_pubnames, > .debug_pubtypes. > >    - Compress or decompress debug info as requested. > > Possible feature: > >    - Join split dwarf .dwo files in a si...

...'s something that GDB insists on having. (It turns out that the standard operator was defined in DWARF 3, so we also have to emit the GNU operator if we're producing DWARF 2. Tuning considerations don't trump what the standard says.) Another example would be .debug_pubnames and .debug_pubtypes sections. Currently these default to omitted for Darwin and PS4, but included everywhere else. My initial patch for "tuning" changes the PS4 platform criterion to the SCE debugger predicate; quite likely the "not Darwin" criterion ought to be "not LLDB" or in other w...

...or, which means it should be possible to fix this with a smarter implementation). As far as object file sizes go, in the resulting clang binary (2.3GB), the new .debug_names section takes up about 160MB (7%), which isn't negligible, but considering that it supersedes the .debug_pubnames/.debug_pubtypes tables whose combined size is 490MB (21% of the binary), switching to this table (and dropping the other two) will have a positive impact on the binary size. Further reductions can be made by merging the individual indexes into one large index as a part of the link step (which will also increase...

...> > > > > > > > which only emits full definitions of classes in the object file that holds and object’s vtable. > > -- adrian > > > > >>> - LLDB wants the .apple_XXX accelerator tables, GDB wants > >>> .debug_pubnames/.debug_pubtypes > >> > >> Agreed. > >> > >>> So it would be great to have a "-debugger" flag that could be specified > >>> > >>> -debugger=lldb > >>> -debugger=gdb > >>> > >>> Not sure on the option name,...