Summary:
In many cases we can't devirtualize
because definition of vtable is not present. Most of the
time it is caused by inline virtual function not beeing
emitted. Forcing emitting of vtable adds a reference of these
inline virtual functions.
Note that GCC was always doing it.
Reviewers: rjmccall, rsmith, amharc, kuhar
Subscribers: llvm-commits, cfe-commits
Differential Revision: https://reviews.llvm.org/D47108
Co-authored-by: Krzysztof Pszeniczny <krzysztof.pszeniczny@gmail.com>
llvm-svn: 334600
As suggested in the post-commit thread for rL331056, we should match these
clang options with the established vocabulary of the corresponding sanitizer
option. Also, the use of 'strict' is well-known for these kinds of knobs,
and we can improve the descriptive text in the docs.
So this intends to match the logic of D46135 but only change the words.
Matching LLVM commit to match this spelling of the attribute to follow shortly.
Differential Revision: https://reviews.llvm.org/D46236
llvm-svn: 331209
As discussed in the post-commit thread for:
rL330437 ( http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20180423/545906.html )
We need a way to opt-out of a float-to-int-to-float cast optimization because too much
existing code relies on the platform-specific undefined result of those casts when the
float-to-int overflows.
The LLVM changes associated with adding this function attribute are here:
rL330947
rL330950
rL330951
Also as suggested, I changed the LLVM doc to mention the specific sanitizer flag that
catches this problem:
rL330958
Differential Revision: https://reviews.llvm.org/D46135
llvm-svn: 331041
- Remove use of the opencl and amdopencl environment member of the target triple for the AMDGPU target.
- Use a function attribute to communicate to the AMDGPU backend.
Differential Revision: https://reviews.llvm.org/D43735
llvm-svn: 328347
Summary:
Currently, assertion-disabled Clang builds emit value names when generating LLVM IR. This is controlled by the `NDEBUG` macro, and is not easily overridable. In order to get IR output containing names from a release build of Clang, the user must manually construct the CC1 invocation w/o the `-discard-value-names` option. This is less than ideal.
For example, Godbolt uses a release build of Clang, and so when asked to emit LLVM IR the result lacks names, making it harder to read. Manually invoking CC1 on Compiler Explorer is not feasible.
This patch adds the driver options `-fdiscard-value-names` and `-fno-discard-value-names` which allow the user to override the default behavior. If neither is specified, the old behavior remains.
Reviewers: erichkeane, aaron.ballman, lebedev.ri
Reviewed By: aaron.ballman
Subscribers: bogner, cfe-commits
Differential Revision: https://reviews.llvm.org/D42887
llvm-svn: 324498
Summary:
Use monospace for option flags in the PCH section, instead of the
italics that were being used previously.
I believe these used to be links, for which single backticks would
have been appropriate, but since they were un-link-ified in
https://reviews.llvm.org/rL275560, I believe monospace is now more
appropriate, and so two backticks are needed.
Test Plan:
Build the `docs-clang-html` target and confirm the options are rendered
using monospace font.
Reviewers: sepavloff, aaron.ballman
Reviewed By: aaron.ballman
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D42005
llvm-svn: 322447
Clang is inherently a cross compiler and can generate code for any target
enabled during build. It however requires to specify many parameters in the
invocation, which could be hardcoded during configuration process in the
case of single-target compiler. The purpose of configuration files is to
make specifying clang arguments easier.
A configuration file is a collection of driver options, which are inserted
into command line before other options specified in the clang invocation.
It groups related options together and allows specifying them in simpler,
more flexible and less error prone way than just listing the options
somewhere in build scripts. Configuration file may be thought as a "macro"
that names an option set and is expanded when the driver is called.
Use of configuration files is described in `UserManual.rst`.
Differential Revision: https://reviews.llvm.org/D24933
llvm-svn: 321621
Clang is inherently a cross compiler and can generate code for any target
enabled during build. It however requires to specify many parameters in the
invocation, which could be hardcoded during configuration process in the
case of single-target compiler. The purpose of configuration files is to
make specifying clang arguments easier.
A configuration file is a collection of driver options, which are inserted
into command line before other options specified in the clang invocation.
It groups related options together and allows specifying them in simpler,
more flexible and less error prone way than just listing the options
somewhere in build scripts. Configuration file may be thought as a "macro"
that names an option set and is expanded when the driver is called.
Use of configuration files is described in `UserManual.rst`.
Differential Revision: https://reviews.llvm.org/D24933
llvm-svn: 321587
Summary:
This change allows generalizing pointers in type signatures used for
cfi-icall by enabling the -fsanitize-cfi-icall-generalize-pointers flag.
This works by 1) emitting an additional generalized type signature
metadata node for functions and 2) llvm.type.test()ing for the
generalized type for translation units with the flag specified.
This flag is incompatible with -fsanitize-cfi-cross-dso because it would
require emitting twice as many type hashes which would increase artifact
size.
Reviewers: pcc, eugenis
Reviewed By: pcc
Subscribers: kcc
Differential Revision: https://reviews.llvm.org/D39358
llvm-svn: 317044
Summary: The Clang option was previously not included in the User's Manual.
Reviewers: anemet, davidxl, hfinkel
Reviewed By: hfinkel
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D34928
llvm-svn: 307193
Summary:
Un-revert https://reviews.llvm.org/D34868, but with a slight tweak to the
documentation to fix an error -- I had used the wrong syntax for a link.
llvm-svn: 306948
Summary:
Depends on https://reviews.llvm.org/D34867.
Add a Clang frontend option to enable optimization remark hotness
thresholds, which were added to LLVM in https://reviews.llvm.org/D34867.
This prevents diagnostics that do not meet a minimum hotness
threshold from being output. When generating optimization remarks for large
codebases with a ton of cold code paths, this option can be used
to limit the optimization remark output at a reasonable size.
Discussion of this change can be read here:
http://lists.llvm.org/pipermail/llvm-dev/2017-June/114377.html
Reviewers: anemet, davidxl, hfinkel
Reviewed By: anemet
Subscribers: fhahn, cfe-commits
Differential Revision: https://reviews.llvm.org/D34868
llvm-svn: 306945
One way to currently test the reproducers is to setup
"FORCE_CLANG_DIAGNOSTICS_CRASH=1" before invoking clang. This simulates
a crash and produces the same contents needed by the reproducers. The
reproducers are specially useful when triaging Modules issues, not only
on crashes, but also for reproducing misleading warnings, errors, etc.
Add a '-gen-reproducer' driver option to clang (or any similar name) and
give users a flag option.
Note that clang already has a -fno-crash-diagnostics, which disables the
crash reproducers. I've decided not to propose "-fcrash-diagnostics"
since it doesn't convey the ideia of reproduction despite a crash.
rdar://problem/24114619
Differential Revision: https://reviews.llvm.org/D27604
llvm-svn: 300109
Added description of a new feature that allows to specify
vendor extension in flexible way using compiler pragma instead
of modifying source code directly (committed in clang@r289979).
Review: D29829
llvm-svn: 295313
Summary: Add missing flag to UsersManual
It would be good to merge it to 4.0 branch.
Reviewers: hans
Subscribers: cfe-commits
Differential Revision: https://reviews.llvm.org/D28727
llvm-svn: 292112
This time, make ignored options, such as /utf-8, show up as well if they
have help text.
Also, since we're now exposing -fdelayed-template-parsing, add help text
to the -fno version so that shows up as well.
llvm-svn: 291798
This was accidentally removed in r260506, even though we only support
non-allocatable global register variables. The general (allocatable) case
is explicitly not supported.
Differential Revision: https://reviews.llvm.org/D27473
llvm-svn: 289455
Original commit message:
Add -fdiagnostics-show-hotness
Summary:
I've recently added the ability for optimization remarks to include the
hotness of the corresponding code region. This uses PGO and allows
filtering of the optimization remarks by relevance. The idea was first
discussed here:
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334
The general goal is to produce a YAML file with the remarks. Then, an
external tool could dynamically filter these by hotness and perhaps by
other things.
That said it makes sense to also expose this at the more basic level
where we just include the hotness info with each optimization remark.
For example, in D22694, the clang flag was pretty useful to measure the
overhead of the additional analyses required to include hotness.
(Without the flag we don't even run the analyses.)
For the record, Hal has already expressed support for the idea of this
patch on IRC.
Differential Revision: https://reviews.llvm.org/D23284
llvm-svn: 281293
Summary:
I've recently added the ability for optimization remarks to include the
hotness of the corresponding code region. This uses PGO and allows
filtering of the optimization remarks by relevance. The idea was first
discussed here:
http://thread.gmane.org/gmane.comp.compilers.llvm.devel/98334
The general goal is to produce a YAML file with the remarks. Then, an
external tool could dynamically filter these by hotness and perhaps by
other things.
That said it makes sense to also expose this at the more basic level
where we just include the hotness info with each optimization remark.
For example, in D22694, the clang flag was pretty useful to measure the
overhead of the additional analyses required to include hotness.
(Without the flag we don't even run the analyses.)
For the record, Hal has already expressed support for the idea of this
patch on IRC.
Differential Revision: https://reviews.llvm.org/D23284
llvm-svn: 281276
remark flags. For now I'm checking in a copy of the built documentation, but we
can replace this with a placeholder (as we do for the attributes reference
documentation) once we enable building this server-side.
llvm-svn: 281192
to CC1, which are translated to function attributes and can e.g. be mapped on
build attributes FP_exceptions and FP_denormal. Setting these build attributes
allows better selection of floating point libraries.
Differential Revision: https://reviews.llvm.org/D23840
llvm-svn: 280064
A number of warnings still remain, but these were the last of the
"unlexable code"-related ones (AFAICT).
I changed a few examples in docs/UsersManual.rst to showcase
-Wextra-tokens because it's already documented (-Wmultichar isn't), and
the sphinx C lexer apparently can't handle char literals like 'ab'. It
seemed like a better overall approach than just marking the code blocks
as none or console.
llvm-svn: 273232
This patch adds the commandline option -mcompact-branches={never,optimal,always),
which controls how LLVM generates compact branches for MIPSR6 targets. By default,
the compact branch policy is 'optimal' where LLVM will generate the most
appropriate branch for any situation. The 'never' and 'always' policy will disable
or always generate compact branches wherever possible respectfully.
Reviewers: dsanders, vkalintiris, atanasyan
Differential Revision: http://reviews.llvm.org/D20729
llvm-svn: 271000
It makes compiler-rt tests fail if the gold plugin is enabled.
Revert "Rework interface for bitset-using features to use a notion of LTO visibility."
Revert "Driver: only produce CFI -fvisibility= error when compiling."
Revert "clang/test/CodeGenCXX/cfi-blacklist.cpp: Exclude ms targets. They would be non-cfi."
llvm-svn: 267871
Bitsets, and the compiler features they rely on (vtable opt, CFI),
only have visibility within the LTO'd part of the linkage unit. Therefore,
only enable these features for classes with hidden LTO visibility. This
notion is based on object file visibility or (on Windows)
dllimport/dllexport attributes.
We provide the [[clang::lto_visibility_public]] attribute to override the
compiler's LTO visibility inference in cases where the class is defined
in the non-LTO'd part of the linkage unit, or where the ABI supports
calling classes derived from abstract base classes with hidden visibility
in other linkage units (e.g. COM on Windows).
If the cross-DSO CFI mode is enabled, bitset checks are emitted even for
classes with public LTO visibility, as that mode uses a separate mechanism
to cause bitsets to be exported.
This mechanism replaces the whole-program-vtables blacklist, so remove the
-fwhole-program-vtables-blacklist flag.
Because __declspec(uuid()) now implies [[clang::lto_visibility_public]], the
support for the special attr:uuid blacklist entry is removed.
Differential Revision: http://reviews.llvm.org/D18635
llvm-svn: 267784
This patch introduces the -fwhole-program-vtables flag, which enables the
whole-program vtable optimization feature (D16795) in Clang.
Differential Revision: http://reviews.llvm.org/D16821
llvm-svn: 261767
After some experiments I discovered that clang doesn't support static
initialization of flexible array members in full, so restored this paragraph in
"GCC extensions not implemented yet" list.
llvm-svn: 260519
#pragma weak, global register variables and static initialization of flexible
array members are supported now, so they are removed from "GCC extensions not
implemented yet" list.
Differential Revision: http://reviews.llvm.org/D16851
llvm-svn: 260506
Summary:
MSVC's driver accepts all unknown arguments but warns about them. clang
by default rejects all unknown arguments. This causes issues
specifically with build systems such as autoconf which liberally pass
things such as $LDFLAGS to the compiler and expect everything to work.
This patch teaches clang-cl to ignore unknown driver arguments.
Reviewers: rnk
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D16511
llvm-svn: 258720
This is part of a new statistics gathering feature for the sanitizers.
See clang/docs/SanitizerStats.rst for further info and docs.
Differential Revision: http://reviews.llvm.org/D16175
llvm-svn: 257971
Adds driver options named -glldb and -gsce to mean -g plus tuning for
lldb and SCE debuggers respectively; the existing -ggdb option does
the same for gdb. Existing options -ggdb0, -ggdb1 etc. unpack into
-ggdb -g<N>. (There will not be -glldb<N> or -gsce<N> options.) The
tuning gets a target-specific default in the driver, and is passed
into cc1 with the new -debugger-tuning option.
As fallout, fixes where '-gsplit-dwarf -g0' would ignore the -g0 part
on Linux.
Differential Revision: http://reviews.llvm.org/D15651
llvm-svn: 256104
Clang-side cross-DSO CFI.
* Adds a command line flag -f[no-]sanitize-cfi-cross-dso.
* Links a runtime library when enabled.
* Emits __cfi_slowpath calls is bitset test fails.
* Emits extra hash-based bitsets for external CFI checks.
* Sets a module flag to enable __cfi_check generation during LTO.
This mode does not yet support diagnostics.
llvm-svn: 255694
There's no way to make a flag alias to two flags, so add a /WCL4 flag that
maps to the All, Extra diag groups. Fixes PR25563.
http://reviews.llvm.org/D15350
llvm-svn: 255382
Patch turns on OpenMP support in clang by default after fixing OpenMP buildbots.
Differential Revision: http://reviews.llvm.org/D13803
llvm-svn: 255223
Summary:
1. Move MSan-specific flags and features from user manual to MSan page.
2. Update current status / list of supported platforms.
Reviewers: eugenis, kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15246
llvm-svn: 254788
Use proper headling levels in CFI doc. Before that, all sections
were considered a subsection of "Introduction".
Reviewers: pcc, kcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D15237
llvm-svn: 254771
Summary:
Create a separate page describing UBSan tool, move the description of
fine-grained checks there, provide extra information about supported
platforms, symbolization etc. This text is compiled from four parts:
* Existing documentation copied from User's Manual
* Layout used in documentation for another sanitizers (ASan, MSan etc.)
* Text written from scratch
* Small parts taken from Michael Morrison's attempt at creating UBSan
page:
http://lists.llvm.org/pipermail/llvm-commits/Week-of-Mon-20141215/249503.html
Reviewers: kcc, rsmith, silvas
Subscribers: tberghammer, danalbert, srhines, kcc
Differential Revision: http://reviews.llvm.org/D15217
llvm-svn: 254733
Summary:
Describe the compile and runtime flags to enable MemorySanitizer
detection of use-after-destroy.
Reviewers: eugenis
Subscribers: llvm-commits
Differential Revision: http://reviews.llvm.org/D12914
Revise doc description of use-after-dtor.
Change wording to specify memory no longer readable.
llvm-svn: 247871
This patch adds flags -fno-profile-instr-generate and
-fno-profile-instr-use, and the GCC aliases -fno-profile-generate and
-fno-profile-use.
These flags are used in situations where users need to disable profile
generation or use for specific files in a build, without affecting other
files.
llvm-svn: 244153
This will be used for old targets like Android that do not
support ELF TLS models.
Differential Revision: http://reviews.llvm.org/D10524
llvm-svn: 243441
This patch adds support for specifying where the profile is emitted in a
way similar to GCC. These flags are used to specify directories instead
of filenames. When -fprofile-generate=DIR is used, the compiler will
generate code to write to <DIR>/default.profraw.
The patch also adds a couple of extensions: LLVM_PROFILE_FILE can still be
used to override the directory and file name to use and -fprofile-use
accepts both directories and filenames.
To simplify the set of flags used in the backend, all the flags get
canonicalized to -fprofile-instr-{generate,use} when passed to the
backend. The decision to use a default name for the profile is done
in the driver.
llvm-svn: 241825
Summary:
This is unfortunate, but would let us land http://reviews.llvm.org/D10467,
that makes ToolChains responsible for computing the set of sanitizers
they support.
Unfortunately, Darwin ToolChains doesn't know about actual OS they
target until ToolChain::TranslateArgs() is called. In particular, it
means we won't be able to construct SanitizerArgs for these ToolChains
before that.
This change removes SanitizerArgs::needsLTO() method, so that now
ToolChain::IsUsingLTO(), which is called very early, doesn't need
SanitizerArgs to implement this method.
Docs and test cases are updated accordingly. See
https://llvm.org/bugs/show_bug.cgi?id=23539, which describes why we
start all these.
Test Plan: regression test suite
Reviewers: pcc
Subscribers: cfe-commits
Differential Revision: http://reviews.llvm.org/D10560
llvm-svn: 240170
This causes programs compiled with this flag to print a diagnostic when
a control flow integrity check fails instead of aborting. Diagnostics are
printed using UBSan's runtime library.
The main motivation of this feature over -fsanitize=vptr is fidelity with
the -fsanitize=cfi implementation: the diagnostics are printed under exactly
the same conditions as those which would cause -fsanitize=cfi to abort the
program. This means that the same restrictions apply regarding compiling
all translation units with -fsanitize=cfi, cross-DSO virtual calls are
forbidden, etc.
Differential Revision: http://reviews.llvm.org/D10268
llvm-svn: 240109
This flag controls whether a given sanitizer traps upon detecting
an error. It currently only supports UBSan. The existing flag
-fsanitize-undefined-trap-on-error has been made an alias of
-fsanitize-trap=undefined.
This change also cleans up some awkward behavior around the combination
of -fsanitize-trap=undefined and -fsanitize=undefined. Previously we
would reject command lines containing the combination of these two flags,
as -fsanitize=vptr is not compatible with trapping. This required the
creation of -fsanitize=undefined-trap, which excluded -fsanitize=vptr
(and -fsanitize=function, but this seems like an oversight).
Now, -fsanitize=undefined is an alias for -fsanitize=undefined-trap,
and if -fsanitize-trap=undefined is specified, we treat -fsanitize=vptr
as an "unsupported" flag, which means that we error out if the flag is
specified explicitly, but implicitly disable it if the flag was implied
by -fsanitize=undefined.
Differential Revision: http://reviews.llvm.org/D10464
llvm-svn: 240105
This patch adds the -fsanitize=safe-stack command line argument for clang,
which enables the Safe Stack protection (see http://reviews.llvm.org/D6094
for the detailed description of the Safe Stack).
This patch is our implementation of the safe stack on top of Clang. The
patches make the following changes:
- Add -fsanitize=safe-stack and -fno-sanitize=safe-stack options to clang
to control safe stack usage (the safe stack is disabled by default).
- Add __attribute__((no_sanitize("safe-stack"))) attribute to clang that can be
used to disable the safe stack for individual functions even when enabled
globally.
Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
Lab at EPFL; updates and upstreaming by myself.
Differential Revision: http://reviews.llvm.org/D6095
llvm-svn: 239762
This clarifies the relationship between instrumentation and sampling based PGO,
code coverage analysis and the different formats supported by sample
profiling.
llvm-svn: 238504
NMake is a Make-like builder that comes with Microsoft Visual Studio.
Jom (https://wiki.qt.io/Jom) is an NMake-compatible build tool.
Dependency files for NMake/Jom need to use double-quotes to wrap
filespecs containing special characters, instead of the backslash
escapes that GNU Make wants.
Adds the -MV option, which specifies to use double-quotes as needed
instead of backslash escapes when writing the dependency file.
Differential Revision: http://reviews.llvm.org/D9260
llvm-svn: 235903
Richard Smith