Based on feedback from Paul Robinson on 38c09ea that the 'mangled' mode
is only useful as an LLVM-developer-internal tool in combination with
llvm-dwarfdump --verify, so demote that to a frontend-only (not driver)
option. The driver support is simply -g{no-,}simple-template-names to
switch on simple template names, without the option to use the mangled
template name scheme there.
This is to build the foundation of a new debug info feature to use only
the base name of template as its debug info name (eg: "t1" instead of
the full "t1<int>"). The intent being that a consumer can still retrieve
all that information from the DW_TAG_template_*_parameters.
So gno-simple-template-names is business as usual/previously ("t1<int>")
=simple is the simplified name ("t1")
=mangled is a special mode to communicate the full information, but
also indicate that the name should be able to be simplified. The data
is encoded as "_STNt1|<int>" which will be matched with an
llvm-dwarfdump --verify feature to deconstruct this name, rebuild the
original name, and then try to rebuild the simple name via the DWARF
tags - then compare the latter and the former to ensure that all the
data necessary to fully rebuild the name is present.
Constructor homing reduces the amount of class type info that is emitted
by emitting conmplete type info for a class only when a constructor for
that class is emitted.
This will mainly reduce the amount of duplicate debug info in object
files. In Chrome enabling ctor homing decreased total build directory sizes
by about 30%.
It's also expected that some class types (such as unused classes)
will no longer be emitted in the debug info. This is fine, since we wouldn't
expect to need these types when debugging.
In some cases (e.g. libc++, https://reviews.llvm.org/D98750), classes
are used without calling the constructor. Since this is technically
undefined behavior, enabling constructor homing should be fine.
However Clang now has an attribute
`__attribute__((standalone_debug))` that can be used on classes to
ignore ctor homing.
Bug: https://bugs.llvm.org/show_bug.cgi?id=46537
Differential Revision: https://reviews.llvm.org/D106084
While GNU as only allows the directory form of the .file directive for DWARF v5,
the integrated assembler prefers the directory form on all DWARF versions
(-fdwarf-directory-asm).
We currently set CC1 -fno-dwarf-directory-asm for -fno-integrated-as -gdwarf-5
which may cause the directory entry 0 and the filename entry 0 to be incorrect
(see D105662 and the example below). This patch makes -fno-integrated-as -gdwarf-5 use
-fdwarf-directory-asm as well.
```
cd /tmp/c
before
% clang -g -gdwarf-5 -fno-integrated-as e/a.c -S -o - | grep '\.file.*0'
.file 0 "/tmp/c/e/a.c" md5 0x97e31cee64b4e58a4af8787512d735b6
% clang -g -gdwarf-5 -fno-integrated-as e/a.c -c
% llvm-dwarfdump a.o | grep include_directories
include_directories[ 0] = "/tmp/c/e"
after
% clang -g -gdwarf-5 -fno-integrated-as e/a.c -S -o - | grep '\.file.*0'
.file 0 "/tmp/c" "e/a.c" md5 0x97e31cee64b4e58a4af8787512d735b6
% clang -g -gdwarf-5 -fno-integrated-as e/a.c -c
% llvm-dwarfdump a.o | grep include_directories
include_directories[ 0] = "/tmp/c"
```
Reviewed By: #debug-info, dblaikie, osandov
Differential Revision: https://reviews.llvm.org/D105835
For DBX, it does not handle column info well. Set -gno-column-info
by default for DBX.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D99703
Based on this debugger type, for now, we plan to:
1: use inline string by default for XCOFF DWARF
2: generate no column info for debug line table.
Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D99400
@ikudrin enabled support for dwarf64 in D87011. Adding a clang flag so it can be used through that compilation pass.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D90507
This is to enable --allow-unused-duplicates=false. This prefix appears
to be outdated and intentionally unused.
Differential Revision: https://reviews.llvm.org/D90430
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.
Differential Revision: https://reviews.llvm.org/D88603
Since Wasm comdat sections work similarly to ELF, we can use that mechanism
to eliminate duplicate dwarf type information in the same way.
Differential Revision: https://reviews.llvm.org/D88603
Fixes pr/11710.
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Resubmit after breaking Windows and OSX builds.
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D80242
Summary:
-debug-info-kind=constructor reduces the amount of class debug info that
is emitted; this patch switches to using this as the default.
Constructor homing emits the complete type info for a class only when the
constructor is emitted, so it is expected that there will be some classes that
are not defined in the debug info anymore because they are never constructed,
and we shouldn't need debug info for these classes.
I compared the PDB files for clang, and there are 273 class types that are defined with `=limited`
but not with `=constructor` (out of ~60,000 total class types).
We've looked at a number of the types that are no longer defined with =constructor. The vast
majority of cases are something like class A is used as a parameter in a member function of
some other class B, which is emitted. But the function that uses class A is never called, and class A
is never constructed, and therefore isn't emitted in the debug info.
Bug: https://bugs.llvm.org/show_bug.cgi?id=46537
Subscribers: aprantl, cfe-commits, lldb-commits
Tags: #clang, #lldb
Differential Revision: https://reviews.llvm.org/D79147
Making -g[no-]column-info opt out reduces the length of a typical CC1 command line.
Additionally, in a non-debug compile, we won't see -dwarf-column-info.
Serialized remarks contain debug locations for each remark, by storing a
file path, a line, and a column.
Also, remarks support being embedded in a .dSYM bundle using a separate
section in object files, that is found by `dsymutil` through the debug
map.
In order for tools to map addresses to source and display remarks in the
source, we need line tables, and in order for `dsymutil` to find the
object files containing the remark section, we need to keep the debug
map around.
Differential Revision: https://reviews.llvm.org/D71325
LLDB reads the various .apple* accelerator tables (and in the near
future: the DWARF 5 accelerator tables) which should make
.gnu_pubnames redundant. This changes the Clang driver to no longer
pass -ggnu-pubnames when tuning for LLDB.
Thanks to David Blaikie for pointing this out!
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20190422/thread.html#646062
rdar://problem/50142073
Differential Revision: https://reviews.llvm.org/D67373
llvm-svn: 371530
Older FreeBSD versions included GDB 6.1 and had other tools that were
unable to handle debug information newer than DWARF 2. Those tools have
since been updated. (An old version of GDB is still kept for kernel
crash handling, but the kernel is compiled with an explicit -gdwarf2.)
Reviewed by: dim
Differential Revision: https://reviews.llvm.org/D66760
llvm-svn: 370779
LLDB can't currently handle Clang's default (limit/no-standalone) DWARF,
so platforms that default to LLDB (Darwin) or anyone else manually
requesting LLDB tuning, should also get standalone DWARF.
That doesn't mean a user can't explicitly enable (because they have
other reasons to prefer standalone DWARF (such as that they're only
building half their application with debug info enabled, and half
without - or because they're tuning for GDB, but want to be able to use
it under LLDB too (this is the default on FreeBSD))) or disable (testing
LLDB fixes/improvements that handle no-standalone mode, building C code,
perhaps, which wouldn't have the LLDB<>no-standalone conflict, etc) the
feature regardless of the tuning.
llvm-svn: 358464
`test/Driver/debug-options.c` to ensure that the driver
selects the DWARF 2 version as intended by the test.
Fixes the `test/Driver/debug-options.c` test regression on GreenDragon
on macOS that started failing after r357713.
llvm-svn: 357740
Summary:
In the future, Android releases will support DWARF 5, but we need to
ensure that older targets only have DWARF 4 generated for them. This
patch inserts that verification for all Android releases now. The patch
also fixes 2 minor mistakes (a mistakenly moved RUN line, and the
missing G_DWARF2 check label).
Reviewers: aprantl
Reviewed By: aprantl
Subscribers: chh, pirama, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D60238
llvm-svn: 357713
Implement options in clang to enable recording the driver command-line
in an ELF section.
Implement a new special named metadata, llvm.commandline, to support
frontends embedding their command-line options in IR/ASM/ELF.
This differs from the GCC implementation in some key ways:
* In GCC there is only one command-line possible per compilation-unit,
in LLVM it mirrors llvm.ident and multiple are allowed.
* In GCC individual options are separated by NULL bytes, in LLVM entire
command-lines are separated by NULL bytes. The advantage of the GCC
approach is to clearly delineate options in the face of embedded
spaces. The advantage of the LLVM approach is to support merging
multiple command-lines unambiguously, while handling embedded spaces
with escaping.
Differential Revision: https://reviews.llvm.org/D54487
Clang Differential Revision: https://reviews.llvm.org/D54489
llvm-svn: 349155
Summary:
If you're using the Microsoft ABI, chances are that you want PDBs and
codeview debug info. Currently, everyone has to remember to specific
-gcodeview by default, when it would be nice if the standard -g option
did the right thing by default.
Also, do some related cleanup of -cc1 options. When targetting the MS
C++ ABI, we probably shouldn't pass -debugger-tuning=gdb. We were also
passing -gcodeview twice, which is silly.
Reviewers: smeenai, zturner
Subscribers: aprantl, JDevlieghere, llvm-commits
Differential Revision: https://reviews.llvm.org/D54499
llvm-svn: 346907
Summary:
This saves a lot of relocations in optimized object files (at the cost
of some cost/increase in linked executable bytes), but gold's 32 bit
gdb-index support has a bug (
https://sourceware.org/bugzilla/show_bug.cgi?id=21894 ) so we can't
switch to this unconditionally. (& even if it weren't for that bug, one
might argue that some users would want to optimize in one direction or
the other - prioritizing object size or linked executable size)
Differential Revision: https://reviews.llvm.org/D54243
llvm-svn: 346789
This recommits r341472, which was reverted due to test failures on macos bots.
The issue was that a macos target implies -glldb which, together with
this patch added a -gpubnames switch where there previously wasn't one.
The intentions of those checks was to check that -gpubnames is not
emitted by default so I add an explicit -ggdb arg to those command lines
to get same behavior on all platforms (the fact that -glldb *does* set
-gpubnames is tested by a separate test).
Differential Revision: https://reviews.llvm.org/D51576
llvm-svn: 341564
Summary:
DWARF v5 accelerator tables provide a considerable performance
improvement for lldb and will make the default -glldb behavior same on
all targets (right now we emit apple tables on apple targets, but these
are not controlled by -gpubnames, only by -glldb).
Reviewers: dblaikie
Subscribers: probinson, clayborg, JDevlieghere, aprantl, cfe-commits
Differential Revision: https://reviews.llvm.org/D51576
llvm-svn: 341472
Summary:
Added option -gline-directives-only to support emission of the debug directives
only. It behaves very similar to -gline-tables-only, except that it sets
llvm debug info emission kind to
llvm::DICompileUnit::DebugDirectivesOnly.
Reviewers: echristo
Subscribers: aprantl, fedor.sergeev, JDevlieghere, cfe-commits
Differential Revision: https://reviews.llvm.org/D51177
llvm-svn: 341212
This changes the current default behavior (from emitting pubnames by
default, to not emitting them by default) & moves to matching GCC's
behavior* with one significant difference: -gno(-gnu)-pubnames disables
pubnames even in the presence of -gsplit-dwarf (though -gsplit-dwarf
still by default enables -ggnu-pubnames). This allows users to disable
pubnames (& the new DWARF5 accelerated access tables) when they might
not be worth the size overhead.
* GCC's behavior is that -ggnu-pubnames and -gpubnames override each
other, and that -gno-gnu-pubnames and -gno-pubnames act as synonyms and
disable either kind of pubnames if they come last. (eg: -gpubnames
-gno-gnu-pubnames causes no pubnames (neither gnu or standard) to be
emitted)
llvm-svn: 340206
Currently, support for debug_types is only present for ELF and trying to
pass -fdebug-types-section for other targets results in a crash in the
backend. Until this is fixed, we should emit a diagnostic in the front
end when the option is passed for non-linux targets.
Differential revision: https://reviews.llvm.org/D49594
llvm-svn: 337717
It means the same thing as -mllvm; there isn't any reason to have two
options which do the same thing.
Differential Revision: https://reviews.llvm.org/D45109
llvm-svn: 329965
In DWARF v5 the Line Number Program Header is extensible, allowing values with
new content types. This vendor extension to DWARF v5 allows source text to be
embedded directly in the line tables of the debug line section.
Add new flag (-g[no-]embed-source) to Driver and CC1 which indicates
that source should be passed through to LLVM during CodeGen.
Differential Revision: https://reviews.llvm.org/D42766
llvm-svn: 326102
This is recommit of r302775, reverted in r302777 due to a fail in
clang-tidy. Original mesage is below.
Now if clang driver is given wrong arguments, in some cases it
continues execution and returns zero code. This change fixes this
behavior.
The fix revealed some errors in clang test set.
File test/Driver/gfortran.f90 added in r118203 checks forwarding
gfortran flags to GCC. Now driver reports error on this file, because
the option -working-directory implemented in clang differs from the
option with the same name implemented in gfortran, in clang the option
requires argument, in gfortran does not.
In the file test/Driver/arm-darwin-builtin.c clang is called with
options -fbuiltin-strcat and -fbuiltin-strcpy. These option were removed
in r191435 and now clang reports error on this test.
File arm-default-build-attributes.s uses option -verify, which is not
supported by driver, it is cc1 option.
Similarly, the file split-debug.h uses options -fmodules-embed-all-files
and -fmodule-format=obj, which are not supported by driver.
Other revealed errors are mainly mistypes.
Differential Revision: https://reviews.llvm.org/D33013
llvm-svn: 303756
Now if clang driver is given wrong arguments, in some cases it
continues execution and returns zero code. This change fixes this
behavior.
The fix revealed some errors in clang test set.
File test/Driver/gfortran.f90 added in r118203 checks forwarding
gfortran flags to GCC. Now driver reports error on this file, because
the option -working-directory implemented in clang differs from the
option with the same name implemented in gfortran, in clang the option
requires argument, in gfortran does not.
In the file test/Driver/arm-darwin-builtin.c clang is called with
options -fbuiltin-strcat and -fbuiltin-strcpy. These option were removed
in r191435 and now clang reports error on this test.
File arm-default-build-attributes.s uses option -verify, which is not
supported by driver, it is cc1 option.
Similarly, the file split-debug.h uses options -fmodules-embed-all-files
and -fmodule-format=obj, which are not supported by driver.
Other revealed errors are mainly mistypes.
Differential Revision: https://reviews.llvm.org/D33013
llvm-svn: 302775
System utilities such as atos only support DWARF 4 on OS X 10.11+ and
iOS 9+. We thus want to enable DWARF 4 only if the deployment target
has a recent enough operating system version and use DWARF 2 for older
systems.
<rdar://problem/28766743>
llvm-svn: 284416
The -gmodules option is all about putting debug type info into clang
modules and for line tables the type information is irrelevant, so
combining these two options makes no sense.
This commmit fixes the behavior to match the one documented on the
clang man page: the last -g... option wins.
<rdar://problem/27059770>
llvm-svn: 283810
Summary:
This is the clang part of D15966. In rL256104, debugger tuning was
added to the clang driver, and again the default for FreeBSD was set to
lldb. The default needs to be gdb instead.
Reviewers: emaste, probinson
Subscribers: cfe-commits, emaste
Differential Revision: http://reviews.llvm.org/D15967
llvm-svn: 257104
David Blaikie