Em Tue, Oct 04, 2022 at 03:07:57PM -0300, Arnaldo Carvalho de Melo escreveu:
> Em Tue, Oct 04, 2022 at 10:25:31AM -0300, Arnaldo Carvalho de Melo escreveu:
> > On October 4, 2022 9:33:05 AM GMT-03:00, Nick Clifton <nickc@xxxxxxxxxx> wrote:
> > >Hi Arnaldo,
> > >
> > >>> <0><c>: Abbrev Number: 3 (DW_TAG_unspecified_type) <--- the problematic TAG
> > >
> > >>> <1><29>: Abbrev Number: 2 (DW_TAG_subprogram)
> > >>> <2a> DW_AT_name : (indirect string, offset: 0x2e): entry_ibpb
> > >>> <2e> DW_AT_type : <0xc>
> > >
> > >If it helps the tag is used to tell consumers like GDB that the return
> > >type of specific functions (eg entry_ibpb in the above example) is unknown.
>
> > Sure helps, thanks!
>
> > I noticed this is for assembly source code, I'll add it as a special
> > "type" and probably for BTF mask it to void.
>
> s/mask/map/g
I just committed the patch below, now to support
DW_TAG_unspecified_type...
- Arnaldo
commit 79d9a783ea74797aa4304009e0cf1bdb9235fcf4
Author: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
Date: Tue Oct 4 18:09:33 2022 -0300
pahole: Support '--lang/--lang_exclude=asm'
It is disjoint from the other languages and then the first simple
implementation of language inclusion/exclusion didn't support it, add
an special case to test against 0x8001 (DW_LANG_Mips_Assembler) to cover
that.
This is needed as recently compilers started to add DWARF constructs to
represent asm CUs that broke pahole as it didn't support
DW_TAG_unspecified_type as a "type", so add it in case in the future we
want to exclude such CUs.
The DW_TAG_unspecified_type tag is going to be supported in the next
csets tho.
We also may want this to exclude new tags that aren't supported in BTF,
etc.
Cc: Martin Liška <mliska@xxxxxxx>
Cc: Nick Clifton <nickc@xxxxxxxxxx>
Signed-off-by: Arnaldo Carvalho de Melo <acme@xxxxxxxxxx>
diff --git a/dwarves.c b/dwarves.c
index 9589747f49f8f3a7..0405592ce0a540a5 100644
--- a/dwarves.c
+++ b/dwarves.c
@@ -2240,6 +2240,9 @@ int lang__str2int(const char *lang)
[DW_LANG_UPC] = "upc",
};
+ if (strcasecmp(lang, "asm") == 0)
+ return DW_LANG_Mips_Assembler;
+
// c89 is the first, bliss is the last, see /usr/include/dwarf.h
for (int id = DW_LANG_C89; id <= DW_LANG_BLISS; ++id)
if (languages[id] && strcasecmp(lang, languages[id]) == 0)
diff --git a/man-pages/pahole.1 b/man-pages/pahole.1
index d752ccbeb297d9d7..45a21af500d94772 100644
--- a/man-pages/pahole.1
+++ b/man-pages/pahole.1
@@ -378,7 +378,7 @@ Only process compilation units built from source code written in the specified l
Supported languages:
- ada83, ada95, bliss, c, c89, c99, c11, c++, c++03, c++11, c++14, cobol74,
+ ada83, ada95, asm, bliss, c, c89, c99, c11, c++, c++03, c++11, c++14, cobol74,
cobol85, d, dylan, fortran77, fortran90, fortran95, fortran03, fortran08,
go, haskell, java, julia, modula2, modula3, objc, objc++, ocaml, opencl,
pascal83, pli, python, renderscript, rust, swift, upc
