[this re-applies c0176916a4824812d25a5a22c4ff7c95857b0cd6
with the correct commit message and phabricator link]
This addresses point 1 of PR44213.
https://bugs.llvm.org/show_bug.cgi?id=44213
The DW_AT_LLVM_sysroot attribute is used for Clang module debug info,
to allow LLDB to import a Clang module from source. Currently it is
part of each DW_TAG_module, however, it is the same for all modules in
a compile unit. It is more efficient and less ambiguous to store it
once in the DW_TAG_compile_unit.
This should have no effect on DWARF consumers other than LLDB.
Differential Revision: https://reviews.llvm.org/D71732
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.
This attribute only appears in Clang module debug info.
Differential Revision: https://reviews.llvm.org/D71722
Partially reverts 0a2be46cfdb698fefcc860a56b47dde0884d5335 as it turned
out to cause redundant module rebuilds in multi-process incremental builds.
When a module was getting out of date, all compilation processes started at the
same time were marking it as `ToBuild`. So each process was building the same
module instead of checking if it was built by someone else and using that
result. In addition to the work duplication, contention on the same .pcm file
wasn't making builds faster.
Note that for a single-process build this change would cause redundant module
reads and validations. But reading a module is faster than building it and
multi-process builds are more common than single-process. So I'm willing to
make such a trade-off.
rdar://problem/54395127
Reviewed By: dexonsmith
Differential Revision: https://reviews.llvm.org/D72860
Allow to build PCH's (with -building-pch-with-obj and the extra .o file)
with -fmodules-codegen -fmodules-debuginfo to allow emitting shared code
into the extra .o file, similarly to how it works with modules. A bit of
a misnomer, but the underlying functionality is the same. This saves up
to 20% of build time here.
Differential Revision: https://reviews.llvm.org/D69778
If a header contains 'extern template', then the template should be provided
somewhere by an explicit instantiation, so it is not necessary to generate
a copy. Worse, this can lead to an unresolved symbol, because the codegen's
object file will not actually contain functions from such a template
because of the GVA_AvailableExternally, but the object file for the explicit
instantiation will not contain them either because it will be blocked
by the information provided by the module.
Differential Revision: https://reviews.llvm.org/D69779
This is a purely cosmetic change that is NFC in terms of the binary
output. I bugs me that I called the attribute DW_AT_LLVM_isysroot
since the "i" is an artifact of GCC command line option syntax
(-isysroot is in the category of -i options) and doesn't carry any
useful information otherwise.
This attribute only appears in Clang module debug info.
Differential Revision: https://reviews.llvm.org/D71722
Jenkins sometimes starts a new working directory by appending @2 (or
incrementing the number if the @n suffix is already there). This causes
several clang tests to fail as:
s@INPUT_DIR@%/S/Inputs@g
gets expanded to the invalid:
s@INPUT_DIR@/path/to/workdir@2/Inputs@g
~~~~~~~~~~
where the part marked with ~'s is interpreted as the flags. These are
invalid and the test fails.
Previous fixes simply exchanged the @ character for another like | but
that's just moving the problem. Address it by adding an expansion that
escapes the @ character we're using as a delimiter as well as other magic
characters in the replacement of sed's s@@@.
There's still room for expansions to cause trouble though. One I ran into
while testing this was that having a directory called foo@bar causes lots
of `CHECK-NOT: foo` directives to match. There's also things like
directories containing `\1`
Keys in a virtual file system can be in Posix or Windows form or even
a combination of the two. Many VFS tests (and a few Clang tests) were
XFAILed on Windows because of false negatives when comparing paths.
First, we default CaseSenstive to false on Windows. This allows
drive letters like "D:" to match "d:". Windows filesystems are, by
default, case insensitive, so this makes sense even beyond the drive
letter.
Second, we allow slashes to match backslashes when they're used as the
root component of a path.
Both of these changes are limited to RedirectingFileSystems, so there's
little chance of affecting other path handling.
These changes allow eleven of the VFS tests to pass on Windows as well
as three other Clang tests, so they have re-enabled.
This solves the majority of PR43272. Additional VFS test failures will
be fixed in separate patches.
Differential Revision: https://reviews.llvm.org/D69958
Summary:
When files often get touched during builds, the mtime based validation
leads to different problems in implicit modules builds, even when the
content doesn't actually change:
- Modules only: module invalidation due to out of date files. Usually causing rebuild traffic.
- Modules + PCH: build failures because clang cannot rebuild a module if it comes from building a PCH.
- PCH: build failures because clang cannot rebuild a PCH in case one of the input headers has different mtime.
This patch proposes hashing the content of input files (headers and
module maps), which is performed during serialization time. When looking
at input files for validation, clang only computes the hash in case
there's a mtime mismatch.
I've tested a couple of different hash algorithms availble in LLVM in
face of building modules+pch for `#import <Cocoa/Cocoa.h>`:
- `hash_code`: performace diff within the noise, total module cache increased by 0.07%.
- `SHA1`: 5% slowdown. Haven't done real size measurements, but it'd be BLOCK_ID+20 bytes per input file, instead of BLOCK_ID+8 bytes from `hash_code`.
- `MD5`: 3% slowdown. Like above, but BLOCK_ID+16 bytes per input file.
Given the numbers above, the patch uses `hash_code`. The patch also
improves invalidation error msgs to point out which type of problem the
user is facing: "mtime", "size" or "content".
rdar://problem/29320105
Reviewers: dexonsmith, arphaman, rsmith, aprantl
Subscribers: jkorous, cfe-commits, ributzka
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67249
> llvm-svn: 374841
llvm-svn: 374895
Summary:
When files often get touched during builds, the mtime based validation
leads to different problems in implicit modules builds, even when the
content doesn't actually change:
- Modules only: module invalidation due to out of date files. Usually causing rebuild traffic.
- Modules + PCH: build failures because clang cannot rebuild a module if it comes from building a PCH.
- PCH: build failures because clang cannot rebuild a PCH in case one of the input headers has different mtime.
This patch proposes hashing the content of input files (headers and
module maps), which is performed during serialization time. When looking
at input files for validation, clang only computes the hash in case
there's a mtime mismatch.
I've tested a couple of different hash algorithms availble in LLVM in
face of building modules+pch for `#import <Cocoa/Cocoa.h>`:
- `hash_code`: performace diff within the noise, total module cache increased by 0.07%.
- `SHA1`: 5% slowdown. Haven't done real size measurements, but it'd be BLOCK_ID+20 bytes per input file, instead of BLOCK_ID+8 bytes from `hash_code`.
- `MD5`: 3% slowdown. Like above, but BLOCK_ID+16 bytes per input file.
Given the numbers above, the patch uses `hash_code`. The patch also
improves invalidation error msgs to point out which type of problem the
user is facing: "mtime", "size" or "content".
rdar://problem/29320105
Reviewers: dexonsmith, arphaman, rsmith, aprantl
Subscribers: jkorous, cfe-commits, ributzka
Tags: #clang
Differential Revision: https://reviews.llvm.org/D67249
llvm-svn: 374841
That way, lit's builtin 'env' command can be used for the 'env' bit.
Also it's clearer that way that the 'not' shouldn't cover 'env'
failures.
llvm-svn: 374749
This patch provides support for DW_LANG_C_plus_plus_11,
DW_LANG_C_plus_plus_14 tags in the Clang C++ frontend.
Patch by Sourabh Singh Tomar!
Differential Revision: https://reviews.llvm.org/D67613
Reapplies r372663 after adapting a failing test in the LLDB testsuite.
llvm-svn: 372681
This patch provides support for DW_LANG_C_plus_plus_11,
DW_LANG_C_plus_plus_14 tags in the Clang C++ frontend.
Patch by Sourabh Singh Tomar!
Differential Revision: https://reviews.llvm.org/D67613
llvm-svn: 372663
Those conditions may use __has_include, which needs to be rewritten.
The existing code has already tried to rewrite just __has_include,
but it didn't work with macro expansion, so e.g. Qt's
"#define QT_HAS_INCLUDE(x) __has_include(x)" didn't get handled
properly. Since the preprocessor run knows what each condition evaluates
to, just rewrite the entire condition. This of course requires that
the -frewrite-include pass has the same setup as the following
compilation, but that has always been the requirement.
Differential Revision: https://reviews.llvm.org/D63508
llvm-svn: 372248
Summary:
Otherwise the definition (first found) for ObjCInterfaceDecl's might
precede the module one, which will eventually lead to crash, since
diagnoseMissingImport needs one coming from a module.
This behavior changed after Richard's r342018, which started to look
into the definition of ObjCInterfaceDecls.
rdar://problem/49237144
Reviewers: rsmith, arphaman
Subscribers: jkorous, dexonsmith, ributzka, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D66982
llvm-svn: 372039
Part of PR43272, the changes are:
1. Use @ as the sed pattern delimiter instead of : so that the drive
letter in lit substitutions isn't an issue.
2. Use the %/t and %/S substitutions to get paths with forward slashes
to work around string quoting issues in the yaml file.
3. Replace REQUIRES:shell with XFAIL:windows. These tests should pass on
Windows, but do not for reasons that are not yet understood. We would
like to know if they pass unexpectedly.
I was able to remove the XFAILs from two tests, since they already pass
with my sed fix:
clang/test/VFS/module_missing_vfs.m
clang/test/VFS/test_nonmodular.c
Reviewers: amccarth
Differential Revision: https://reviews.llvm.org/D67454
llvm-svn: 371663
This reverts r371497 (git commit 3d7e9ab7b9f8c53aa41420c54970f0fb421004a2)
Reorder `not` with `env` in these two tests so they pass:
Driver/rewrite-map-in-diagnostics.c
Index/crash-recovery-modules.m.
This will not be necessary after D66531 lands.
llvm-svn: 371552
I see in the history for some of these tests REQUIRES:shell was used as
a way to disable tests on Windows because they are flaky there. I tried
not to re-enable such tests, but it's possible that I missed some and
this will re-enable flaky tests on Windows. If so, we should disable
them with UNSUPPORTED:system-windows and add a comment that they are
flaky there. So far as I can tell, the lit internal shell is capable of
running all of these tests, and we shouldn't use REQUIRES:shell as a
proxy for Windows.
llvm-svn: 371478
Marking a module for a rebuild when its signature differs from the
expected one causes redundant module rebuilds for incremental builds.
When a module is updated, its signature changes. But its consumers still
have the old signature and loading them will result in signature
mismatches. It will correctly cause the rebuilds for the consumers but
we don't need to rebuild the common module for each of them as it is
already up to date.
In practice this bug causes longer build times. We are doing more work
than required and only a single process can build a module, so parallel
builds degrade to a single-process mode where extra processes are just
waiting on a file lock.
Fix by not marking a module dependency for a rebuild on signature
mismatch. We'll check if it is up to date when we load it.
rdar://problem/50212358
Reviewers: dexonsmith, bruno, rsmith
Reviewed By: dexonsmith, bruno
Subscribers: jkorous, ributzka, cfe-commits, aprantl
Differential Revision: https://reviews.llvm.org/D66907
llvm-svn: 370274
D63793 removed float-divide-by-zero from the "undefined" set but it
failed to add it to getSupportedSanitizers(), thus the sanitizer is
rejected by the driver:
clang-9: error: unsupported option '-fsanitize=float-divide-by-zero' for target 'x86_64-unknown-linux-gnu'
Also, add SanitizerMask::FloatDivideByZero to a few other masks to make -fsanitize-trap, -fsanitize-recover, -fsanitize-minimal-runtime and -fsanitize-coverage work.
Reviewed By: rsmith, vitalybuka
Differential Revision: https://reviews.llvm.org/D64317
llvm-svn: 365587
`Selector::getIdentifierInfoForSlot` returns NULL if a slot has no
corresponding identifier. Add a boolean to the hash and a NULL check.
rdar://problem/51615164
Reviewers: rtrieu
Reviewed By: rtrieu
Subscribers: dexonsmith, cfe-commits, jkorous
Differential Revision: https://reviews.llvm.org/D63789
llvm-svn: 364664
In some cases, a typedef only strips aways a keyword for a type, keeping the
same name as the root record type. This causes some confusion when the type
is defined in one modules but only forward declared in another. Skipping the
typedef and going straight to the record will avoid this issue.
typedef struct S {} S;
S* s; // S is TypedefType here
struct S;
S* s; // S is RecordType here
llvm-svn: 364119
Summary:
This is the first in a series of changes trying to align clang -cc1
flags for Split DWARF with those of llc. The unfortunate side effect of
having -split-dwarf-output for single file Split DWARF will disappear
again in a subsequent change.
The change is the result of a discussion in D59673.
Reviewers: dblaikie, echristo
Reviewed By: dblaikie
Differential Revision: https://reviews.llvm.org/D63130
llvm-svn: 363494
Found in a bootstrap of LLVM with implicit modules, resulting in a
deadlock of some Orc unit tests with libstdc++ 8.1. An enum was used as
part of the implementation of std::recursive_mutex and this bug resulted
in the constant initialization of zero instead of the desired non-zero
value. => Badness.
Richard Smith tells me neither of these fields are necessarily canonical
& so using declaresSamEntity is the right solution here (rather than
changing both of these Fields to be canonical by construction/from their
source)
llvm-svn: 361428
This patch implements a limited form of autolinking primarily designed to allow
either the --dependent-library compiler option, or "comment lib" pragmas (
https://docs.microsoft.com/en-us/cpp/preprocessor/comment-c-cpp?view=vs-2017) in
C/C++ e.g. #pragma comment(lib, "foo"), to cause an ELF linker to automatically
add the specified library to the link when processing the input file generated
by the compiler.
Currently this extension is unique to LLVM and LLD. However, care has been taken
to design this feature so that it could be supported by other ELF linkers.
The design goals were to provide:
- A simple linking model for developers to reason about.
- The ability to to override autolinking from the linker command line.
- Source code compatibility, where possible, with "comment lib" pragmas in other
environments (MSVC in particular).
Dependent library support is implemented differently for ELF platforms than on
the other platforms. Primarily this difference is that on ELF we pass the
dependent library specifiers directly to the linker without manipulating them.
This is in contrast to other platforms where they are mapped to a specific
linker option by the compiler. This difference is a result of the greater
variety of ELF linkers and the fact that ELF linkers tend to handle libraries in
a more complicated fashion than on other platforms. This forces us to defer
handling the specifiers to the linker.
In order to achieve a level of source code compatibility with other platforms
we have restricted this feature to work with libraries that meet the following
"reasonable" requirements:
1. There are no competing defined symbols in a given set of libraries, or
if they exist, the program owner doesn't care which is linked to their
program.
2. There may be circular dependencies between libraries.
The binary representation is a mergeable string section (SHF_MERGE,
SHF_STRINGS), called .deplibs, with custom type SHT_LLVM_DEPENDENT_LIBRARIES
(0x6fff4c04). The compiler forms this section by concatenating the arguments of
the "comment lib" pragmas and --dependent-library options in the order they are
encountered. Partial (-r, -Ur) links are handled by concatenating .deplibs
sections with the normal mergeable string section rules. As an example, #pragma
comment(lib, "foo") would result in:
.section ".deplibs","MS",@llvm_dependent_libraries,1
.asciz "foo"
For LTO, equivalent information to the contents of a the .deplibs section can be
retrieved by the LLD for bitcode input files.
LLD processes the dependent library specifiers in the following way:
1. Dependent libraries which are found from the specifiers in .deplibs sections
of relocatable object files are added when the linker decides to include that
file (which could itself be in a library) in the link. Dependent libraries
behave as if they were appended to the command line after all other options. As
a consequence the set of dependent libraries are searched last to resolve
symbols.
2. It is an error if a file cannot be found for a given specifier.
3. Any command line options in effect at the end of the command line parsing apply
to the dependent libraries, e.g. --whole-archive.
4. The linker tries to add a library or relocatable object file from each of the
strings in a .deplibs section by; first, handling the string as if it was
specified on the command line; second, by looking for the string in each of the
library search paths in turn; third, by looking for a lib<string>.a or
lib<string>.so (depending on the current mode of the linker) in each of the
library search paths.
5. A new command line option --no-dependent-libraries tells LLD to ignore the
dependent libraries.
Rationale for the above points:
1. Adding the dependent libraries last makes the process simple to understand
from a developers perspective. All linkers are able to implement this scheme.
2. Error-ing for libraries that are not found seems like better behavior than
failing the link during symbol resolution.
3. It seems useful for the user to be able to apply command line options which
will affect all of the dependent libraries. There is a potential problem of
surprise for developers, who might not realize that these options would apply
to these "invisible" input files; however, despite the potential for surprise,
this is easy for developers to reason about and gives developers the control
that they may require.
4. This algorithm takes into account all of the different ways that ELF linkers
find input files. The different search methods are tried by the linker in most
obvious to least obvious order.
5. I considered adding finer grained control over which dependent libraries were
ignored (e.g. MSVC has /nodefaultlib:<library>); however, I concluded that this
is not necessary: if finer control is required developers can fall back to using
the command line directly.
RFC thread: http://lists.llvm.org/pipermail/llvm-dev/2019-March/131004.html.
Differential Revision: https://reviews.llvm.org/D60274
llvm-svn: 360984
Currently `immintrin.h` includes `pconfigintrin.h` and `sgxintrin.h`
which contain inline assembly. It causes failures when building with the
flag `-fno-gnu-inline-asm`.
Fix by excluding functions with inline assembly when this extension is
disabled. So far there was no need to support `_pconfig_u32`,
`_enclu_u32`, `_encls_u32`, `_enclv_u32` on platforms that require
`-fno-gnu-inline-asm`. But if developers start using these functions,
they'll have compile-time undeclared identifier errors which is
preferrable to runtime errors.
rdar://problem/49540880
Reviewers: craig.topper, GBuella, rnk, echristo
Reviewed By: rnk
Subscribers: jkorous, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D61621
llvm-svn: 360630
