Some projects (e.g. FreeBSD) align pointers to the right but expect a
space between the '*' and any pointer qualifiers such as const. To handle
these cases this patch adds a new config option SpaceAroundPointerQualifiers
that can be used to configure whether spaces need to be added before/after
pointer qualifiers.
PointerAlignment = Right
SpaceAroundPointerQualifiers = Default/After:
void *const *x = NULL;
SpaceAroundPointerQualifiers = Before/Both
void * const *x = NULL;
PointerAlignment = Left
SpaceAroundPointerQualifiers = Default/Before:
void* const* x = NULL;
SpaceAroundPointerQualifiers = After/Both
void* const * x = NULL;
PointerAlignment = Middle
SpaceAroundPointerQualifiers = Default/Before/After/Both:
void * const * x = NULL;
Reviewed By: MyDeveloperDay
Differential Revision: https://reviews.llvm.org/D88227
This implements the likelihood attribute for the switch statement. Based on the
discussion in D85091 and D86559 it only handles the attribute when placed on
the case labels or the default labels.
It also marks the likelihood attribute as feature complete. There are more QoI
patches in the pipeline.
Differential Revision: https://reviews.llvm.org/D89210
Old GCC used to aggressively fold VLAs to constant-bound arrays at block
scope in GNU mode. That's non-conforming, and more modern versions of
GCC only do this at file scope. Update Clang to do the same.
Also promote the warning for this from off-by-default to on-by-default
in all cases; more recent versions of GCC likewise warn on this by
default.
This is still slightly more permissive than GCC, as pointed out in
PR44406, as we still fold VLAs to constant arrays in structs, but that
seems justifiable given that we don't support VLA-in-struct (and don't
intend to ever support it), but GCC does.
Differential Revision: https://reviews.llvm.org/D89523
SUMMARY:
In IBM compiler xlclang , there is an option -fnovisibility which suppresses visibility. For more details see: https://www.ibm.com/support/knowledgecenter/SSGH3R_16.1.0/com.ibm.xlcpp161.aix.doc/compiler_ref/opt_visibility.html.
We need to add the option -mignore-xcoff-visibility for compatibility with the IBM AIX OS (as the option is enabled by default in AIX). With this option llvm does not emit any visibility attribute to ASM or XCOFF object file.
The option only work on the AIX OS, for other non-AIX OS using the option will report an unsupported options error.
In AIX OS:
1.1 the option -mignore-xcoff-visibility is enabled by default , if there is not -fvisibility=* and -mignore-xcoff-visibility explicitly in the clang command .
1.2 if there is -fvisibility=* explicitly but not -mignore-xcoff-visibility explicitly in the clang command. it will generate visibility attributes.
1.3 if there are both -fvisibility=* and -mignore-xcoff-visibility explicitly in the clang command. The option "-mignore-xcoff-visibility" wins , it do not emit the visibility attribute.
The option -mignore-xcoff-visibility has no effect on visibility attribute when compile with -emit-llvm option to generated LLVM IR.
Reviewer: daltenty,Jason Liu
Differential Revision: https://reviews.llvm.org/D87451
API Notes are a feature which allows annotation of headers by an
auxiliary file that contains metadata for declarations pertaining to the
associated module. This enables adding attributes to declarations
without requiring modification of the headers, enabling finer grained
control for library headers for consumers without having to modify
external headers.
Differential Revision: https://reviews.llvm.org/D88446
Reviewed By: Richard Smith, Marcel Hlopko
Expand the list of targets that support cfi-icall.
Add ThinLTO everywhere LTO is mentioned. AFAIK all CFI features are
supported with ThinLTO.
Differential Revision: https://reviews.llvm.org/D87717
GCC 7 introduced -fprofile-update={atomic,prefer-atomic} (prefer-atomic is for
best efforts (some targets do not support atomics)) to increment counters
atomically, which is exactly what we have done with -fprofile-instr-generate
(D50867) and -fprofile-arcs (b5ef137c11).
This patch adds the option to clang to surface the internal options at driver level.
GCC 7 also turned on -fprofile-update=prefer-atomic when -pthread is specified,
but it has performance regression
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=89307). So we don't follow suit.
Differential Revision: https://reviews.llvm.org/D87737
Previous description didn't actually state the effect the attribute has on
thread safety analysis (causing analysis to assume the capability is held).
Previous description was also ambiguous about (or slightly overstated) the
noreturn assumption made by thread safety analysis, implying the assumption had
to be true about the function's behavior in general, and not just its behavior
in places where it's used. Stating the assumption specifically should avoid a
perceived need to disable thread safety analysis in places where only asserting
that a specific capability is held would be better.
Reviewed By: aaronpuchert, vasild
Differential Revision: https://reviews.llvm.org/D87629
Add support for expanding the %t filename specifier in LLVM_PROFILE_FILE
to the TMPDIR environment variable. This is supported on all platforms.
On Darwin, TMPDIR is used to specify a temporary application-specific
scratch directory. When testing apps on remote devices, it can be
challenging for the host device to determine the correct TMPDIR, so it's
helpful to have the runtime do this work.
rdar://68524185
Differential Revision: https://reviews.llvm.org/D87332
Currently newer clang-format options cannot be included in .clang-format files, if not all users can be forced to use an updated version.
This patch tries to solve this by adding an option to clang-format, enabling to ignore unknown (newer) options.
Differential Revision: https://reviews.llvm.org/D86137
Some Java style guides and IDEs group Java static imports after
non-static imports. This patch allows clang-format to control
the location of static imports.
Patch by: @bc-lee
Reviewed By: MyDeveloperDay, JakeMerdichAMD
Differential Revision: https://reviews.llvm.org/D87201
The analysis for const-ness of local variables required a view generally useful
matchers that are extracted into its own patch.
They are decompositionDecl and forEachArgumentWithParamType, that works
for calls through function pointers as well.
This is a reupload of https://reviews.llvm.org/D72505, that already landed,
but had to be reverted due to a GCC crash on powerpc
(https://reviews.llvm.org/rG4c48ea68e491cb42f1b5d43ffba89f6a7f0dadc4)
Because this took a long time to adress, i decided to redo this patch and
have a clean workflow.
I try to coordinate with someone that has a PPC to apply this patch and
test for the crash. If everything is fine, I intend to just commit.
If the crash is still happening, i hope to at least find the cause.
Differential Revision: https://reviews.llvm.org/D87588
The summary and very short discussion in D82122 summarizes whats happening here.
In short, liveness talks about variables, or expressions, anything that
has a value. Well, statements just simply don't have a one.
Differential Revision: https://reviews.llvm.org/D82598
This patch introduces the new .bb_addr_map section feature which allows us to emit the bits needed for mapping binary profiles to basic blocks into a separate section.
The format of the emitted data is represented as follows. It includes a header for every function:
| Address of the function | -> 8 bytes (pointer size)
| Number of basic blocks in this function (>0) | -> ULEB128
The header is followed by a BB record for every basic block. These records are ordered in the same order as MachineBasicBlocks are placed in the function. Each BB Info is structured as follows:
| Offset of the basic block relative to function begin | -> ULEB128
| Binary size of the basic block | -> ULEB128
| BB metadata | -> ULEB128 [ MBB.isReturn() OR MBB.hasTailCall() << 1 OR MBB.isEHPad() << 2 ]
The new feature will replace the existing "BB labels" functionality with -basic-block-sections=labels.
The .bb_addr_map section scrubs the specially-encoded BB symbols from the binary and makes it friendly to profilers and debuggers.
Furthermore, the new feature reduces the binary size overhead from 70% bloat to only 12%.
For more information and results please refer to the RFC: https://lists.llvm.org/pipermail/llvm-dev/2020-July/143512.html
Reviewed By: MaskRay, snehasish
Differential Revision: https://reviews.llvm.org/D85408
Adds link/code sample to avoid rendering two dashes as non-ASCII "en dash".
Also make wording a complete sentence.
Reviewed By: nickdesaulniers, tmfink
Differential Revision: https://reviews.llvm.org/D85596
This patch updates the documentation about `__builtin_memcpy_inline` and reorders the sections so it is more consitent and understandable.
Differential Revision: https://reviews.llvm.org/D87458
This adds a `AttributeMacros` configuration option that causes certain
identifiers to be parsed like a __attribute__((foo)) annotation.
This is motivated by our CHERI C/C++ fork which adds a __capability
qualifier for pointer/reference. Without this change clang-format parses
many type declarations as multiplications/bitwise-and instead.
I initially considered adding "__capability" as a new clang-format keyword,
but having a list of macros that should be treated as attributes is more
flexible since it can be used e.g. for static analyzer annotations or other language
extensions.
Example: std::vector<foo * __capability> -> std::vector<foo *__capability>
Depends on D86775 (to apply cleanly)
Reviewed By: MyDeveloperDay, jrtc27
Differential Revision: https://reviews.llvm.org/D86782
They are for more powerful than the current documentation implies, this
adds
* adopting a lock,
* deferring a lock,
* manually unlocking the scoped capability,
* relocking the scoped capability, possibly in a different mode,
* try-relocking the scoped capability.
Also there is now a generic explanation how attributes on scoped
capabilities work. There has been confusion in the past about how to
annotate them (see e.g. PR33504), hopefully this clears things up.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D87066
The old locking attributes had a generic release, but as it turns out
the capability-based attributes have it as well.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D87064
I don't think this is obvious, since try-acquire seemingly contradicts
our usual requirements of "no conditional locking".
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D87065
It's not undefined behavior for an unsigned left shift to overflow (i.e. to
shift bits out), but it has been the source of bugs and exploits in certain
codebases in the past. As we do in other parts of UBSan, this patch adds a
dynamic checker which acts beyond UBSan and checks other sources of errors. The
option is enabled as part of -fsanitize=integer.
The flag is named: -fsanitize=unsigned-shift-base
This matches shift-base and shift-exponent flags.
<rdar://problem/46129047>
Differential Revision: https://reviews.llvm.org/D86000
As suggested by @rsmith on PR47267, by replacing the builtin_memcpy bitcast pattern with builtin_bit_cast we can use _castf32_u32, _castu32_f32, _castf64_u64 and _castu64_f64 inside constant expresssions (constexpr). Although __builtin_bit_cast was added for c++20 it works on all clang c/c++ modes.
Differential Revision: https://reviews.llvm.org/D86398
This enables us to use the __builtin_rotateleft / __builtin_rotateright 8/16/32/64 intrinsics inside constexpr code.
Differential Revision: https://reviews.llvm.org/D86342
This is a first step patch to enable constexpr support and testing to a large number of x86 intrinsics.
All I've done here is provide a DEFAULT_FN_ATTRS_CONSTEXPR variant to our existing DEFAULT_FN_ATTRS tag approach that adds constexpr on c++ builds. The clang cuda headers do something similar.
I've started with POPCNT mainly as its tiny and are wrappers to generic __builtin_* intrinsics which already act as constexpr.
Differential Revision: https://reviews.llvm.org/D86229
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
This fixes an inconsistency: clang -c -gz -fno-integrated-as means SHF_COMPRESSED
while clang -c -gz -fintegrated-as means zlib-gnu.
---
Since July 15, 2015 (binutils-gdb commit
19a7fe52ae3d0971e67a134bcb1648899e21ae1c, included in 2.26), gas
--compress-debug-sections=zlib (gcc -gz) means zlib-gabi:
SHF_COMPRESSED. Before that GCC/binutils used zlib-gnu (.zdebug).
clang's -gz was introduced in rC306115 (Jun 2017) to indicate zlib-gnu. It
is 2020 now and it is not unreasonable to assume users of the new
feature to have new linkers (ld.bfd/gold >= 2.26, lld >= rLLD273661).
Change clang's default accordingly to improve standard conformance.
zlib-gnu becomes out of fashion and gets poorer toolchain support.
Its mangled names confuse tools and are more likely to cause problems.
Reviewed By: compnerd
Differential Revision: https://reviews.llvm.org/D61689
Adds the -fast-16-labels flag, which enables efficient instrumentation
for DFSan when the user needs <=16 labels. The instrumentation
eliminates most branches and most calls to __dfsan_union or
__dfsan_union_load.
Reviewed By: vitalybuka
Differential Revision: https://reviews.llvm.org/D84371
Using -fmodules-* options for PCHs is a bit confusing, so add -fpch-*
variants. Having extra options also makes it simple to do a configure
check for the feature.
Also document the options in the release notes.
Differential Revision: https://reviews.llvm.org/D83623
clang/docs/tools/dump_format_style.py is used to read the comments
from clang/include/clang/Format/Format.h and update the contents of
clang/docs/ClangFormatStyleOptions.rst
Recent changes made these out of date. This commit syncs them by
folding the improved wording back to the comments and then
regenerating the rst file.
Differential Revision: https://reviews.llvm.org/D84103
Check that the implicit cast from `id` used to construct the element
variable in an ObjC for-in statement is valid.
This check is included as part of a new `objc-cast` sanitizer, outside
of the main 'undefined' group, as (IIUC) the behavior it's checking for
is not technically UB.
The check can be extended to cover other kinds of invalid casts in ObjC.
Partially addresses: rdar://12903059, rdar://9542496
Differential Revision: https://reviews.llvm.org/D71491
This implements the default(firstprivate) clause as defined in OpenMP
Technical Report 8 (2.22.4).
Reviewed By: jdoerfert, ABataev
Differential Revision: https://reviews.llvm.org/D75591
We currently have strict floating point/constrained floating point enabled
for all targets. Constrained SDAG nodes get converted to the regular ones
before reaching the target layer. In theory this should be fine.
However, the changes are exposed to users through multiple clang options
already in use in the field, and the changes are _completely_ _untested_
on almost all of our targets. Bugs have already been found, like
"https://bugs.llvm.org/show_bug.cgi?id=45274".
This patch disables constrained floating point options in clang everywhere
except X86 and SystemZ. A warning will be printed when this happens.
Use the new -fexperimental-strict-floating-point flag to force allowing
strict floating point on hosts that aren't already marked as supporting
it (X86 and SystemZ).
Differential Revision: https://reviews.llvm.org/D80952
This patch creates a clang flag to enable SESES. This flag also ensures that
lvi-cfi is on when using seses via clang.
SESES should use lvi-cfi to mitigate returns and indirect branches.
The flag to enable the SESES functionality only without lvi-cfi is now
-x86-seses-enable-without-lvi-cfi to warn users part of the mitigation is not
enabled if they use this flag. This is useful in case folks want to see the
cost of SESES separate from the LVI-CFI.
Reviewed By: sconstab
Differential Revision: https://reviews.llvm.org/D79910
Adds a matcher called `hasDirectBase` for matching the `CXXBaseSpecifier` of a class that directly derives from another class.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D81552
Summary:
This feature was only used in two places, but contributed a non-trivial
amount to the complexity of RecursiveASTVisitor, and was buggy (see my
recent patches where I was fixing the bugs that I noticed). I don't
think the convenience benefit of this feature is worth the complexity.
Besides complexity, another issue with the current state of
RecursiveASTVisitor is the non-uniformity in how it handles different
AST nodes. All AST nodes follow a regular pattern, but operators are
special -- and this special behavior not documented. Correct usage of
RecursiveASTVisitor relies on shadowing member functions with specific
names and signatures. Near misses don't cause any compile-time errors,
incorrectly named or typed methods are just silently ignored. Therefore,
predictability of RecursiveASTVisitor API is quite important.
This change reduces the size of the `clang` binary by 38 KB (0.2%) in
release mode, and by 7 MB (0.3%) in debug mode. The `clang-tidy` binary
is reduced by 205 KB (0.3%) in release mode, and by 5 MB (0.4%) in debug
mode. I don't think these code size improvements are significant enough
to justify this change on its own (for me, the primary motivation is
reducing code complexity), but they I think are a nice side-effect.
Reviewers: rsmith, sammccall, ymandel, aaron.ballman
Reviewed By: rsmith, sammccall, ymandel, aaron.ballman
Subscribers: cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D82921
Added new Macros `AST(_POLYMORPHIC)_MATCHER_REGEX(_OVERLOAD)` that define a matchers that take a regular expression string and optionally regular expression flags. This lets users match against nodes while ignoring the case without having to manually use `[Aa]` or `[A-Fa-f]` in their regex. The other point this addresses is in the current state, matchers that use regular expressions have to compile them for each node they try to match on, Now the regular expression is compiled once when you define the matcher and used for every node that it tries to match against. If there is an error while compiling the regular expression an error will be logged to stderr showing the bad regex string and the reason it couldn't be compiled. The old behaviour of this was down to the Matcher implementation and some would assert, whereas others just would never match. Support for this has been added to the documentation script as well. Support for this has been added to dynamic matchers ensuring functionality is the same between the 2 use cases.
Reviewed By: aaron.ballman
Differential Revision: https://reviews.llvm.org/D82706
If -Wl,object_path_lto,<lto-filename>.o is not passed at link time
when compiling and linking in separate steps with -flto and -g, the
temporary file used for Link Time Optimization is deleted by the linker,
so the executable is missing debug symbols and can't be easily debugged,
and dsymutil can't be run.
Document this behaviour.
Differential revision: https://reviews.llvm.org/D82733
Summary:
https://bugs.llvm.org/show_bug.cgi?id=46383
When the c preprocessor stringizes tokens, the generated string literals
are affected by the whitespace. This means clang-format can affect
codegen silently, adding spaces and newlines to strings. Practically
speaking, the vast majority of cases will be harmless, only affecting
single identifiers or debug macros.
In the interest of doing no harm in other cases though, this introduces
a blacklist option 'WhitespaceSensitiveMacros', which contains a list of
names of function-like macros whose contents should not be touched by
clang-format, period. Clang-format can't automatically detect these
without a real compile context, so users will have to specify it
explicitly (it still beats clang-format off'ing at every invocation).
Defaults include "STRINGIZE", "PP_STRINGIZE", and "BOOST_PP_STRINGIZE".
Subscribers: kristof.beyls, cfe-commits
Tags: #clang
Differential Revision: https://reviews.llvm.org/D82620
Currently on http://clang.llvm.org/docs/ClangFormattedStatus.html there are format stats on files no actually inside the tree but generated by build scripts. These are usually copied from somewhere else. Right now for example there are files from `llvm/utils/release/llvm-package...`. Adding these files bloats the list while not giving an accurate representation of how formatted the repo is.
This addresses this issue by checking the git index and ignoring any folder that doesn't contain tracked files.
I'm still unsure whether it would be better to just do away with the `os.walk` method and just check over every file returned from `git ls-index <project-root>`.
Reviewed By: MyDeveloperDay
Differential Revision: https://reviews.llvm.org/D82707
This fixes a unit test. Otherwise here is the original commit:
1) Shared writable directories like /tmp are a security problem.
2) Systems provide dedicated cache directories these days anyway.
3) This also refines LLVM's cache_directory() on Darwin platforms to use
the Darwin per-user cache directory.
Reviewers: compnerd, aprantl, jakehehrlich, espindola, respindola, ilya-biryukov, pcc, sammccall
Reviewed By: compnerd, sammccall
Subscribers: hiraditya, llvm-commits, cfe-commits
Tags: #clang, #llvm
Differential Revision: https://reviews.llvm.org/D82362
Tianqing Wang