Commit Graph

252 Commits

Author SHA1 Message Date
Alexey Bataev
6b29aa2118 Revert "[OPENMP]Do not use RTTI by default for NVPTX devices."
This reverts commit 23058f9dd4. It breaks
builds of cuda code somehow in some cases.
2020-01-15 17:42:26 -05:00
Alexey Bataev
23058f9dd4 [OPENMP]Do not use RTTI by default for NVPTX devices.
NVPTX does not support RTTI, so disable it by default.
2020-01-14 18:12:06 -05:00
Mark de Wever
b750486c5d [Driver] Avoid copies in range-based for loops
This avoids new warnings due to D68912 adds -Wrange-loop-analysis to -Wall.

Differential Revision: https://reviews.llvm.org/D71527
2019-12-17 21:56:04 +01:00
Tim Northover
44e5879f0f AArch64: add arm64_32 support to Clang. 2019-11-12 12:45:18 +00:00
Peter Waller
6bf5580492 [clang][driver] Add basic --driver-mode=flang support for fortran
This patch adds a new Flang mode. When in Flang mode, the driver will
invoke flang for fortran inputs instead of falling back to the GCC
toolchain as it would otherwise do.

The behaviour of other driver modes are left unmodified to preserve
backwards compatibility.

It is intended that a soon to be implemented binary in the flang project
will import libclangDriver and run the clang driver in the new flang
mode.

Please note that since the binary invoked by the driver is under
development, there will no doubt be further tweaks necessary in future
commits.

* Initial support is added for basic driver phases
  * -E, -fsyntax-only, -emit-llvm -S, -emit-llvm, -S, (none specified)
  * -### tests are added for all of the above
  * This is more than is supported by f18 so far, which will emit errors
    for those options which are unimplemented.

* A test is added that ensures that clang gives a reasonable error
  message if flang is not available in the path (without -###).

* Test that the driver accepts multiple inputs in --driver-mode=flang.

* Test that a combination of C and Fortran inputs run both clang and
  flang in --driver-mode=flang.

* clang/test/Driver/fortran.f95 is fixed to use the correct fortran
  comment character.

Differential revision: https://reviews.llvm.org/D63607
2019-10-30 10:42:22 +00:00
Sergey Dmitriev
a0d83768f1 [Clang][OpenMP Offload] Add new tool for wrapping offload device binaries
This patch removes the remaining part of the OpenMP offload linker scripts which was used for inserting device binaries into the output linked binary. Device binaries are now inserted into the host binary with a help of the wrapper bit-code file which contains device binaries as data. Wrapper bit-code file is dynamically created by the clang driver with a help of new tool clang-offload-wrapper which takes device binaries as input and produces bit-code file with required contents. Wrapper bit-code is then compiled to an object and resulting object is appended to the host linking by the clang driver.

This is the second part of the patch for eliminating OpenMP linker script (please see https://reviews.llvm.org/D64943).

Differential Revision: https://reviews.llvm.org/D68166

llvm-svn: 374219
2019-10-09 20:42:58 +00:00
Puyan Lotfi
c382d03ca8 [clang][ifs] Clang Interface Stubs ToolChain plumbing.
Second Landing Attempt:

This patch enables end to end support for generating ELF interface stubs
directly from clang. Now the following:

clang -emit-interface-stubs -o libfoo.so a.cpp b.cpp c.cpp

will product an ELF binary with visible symbols populated. Visibility attributes
and -fvisibility can be used to control what gets populated.

* Adding ToolChain support for clang Driver IFS Merge Phase
* Implementing a default InterfaceStubs Merge clang Tool, used by ToolChain
* Adds support for the clang Driver to involve llvm-ifs on ifs files.
* Adds -emit-merged-ifs flag, to tell llvm-ifs to emit a merged ifs text file
  instead of the final object format (normally ELF)


Differential Revision: https://reviews.llvm.org/D63978

llvm-svn: 374061
2019-10-08 15:23:14 +00:00
Nico Weber
6713f8235b Revert 373538 and follow-ups 373549 and 373552.
They break tests on (at least) macOS.

llvm-svn: 373556
2019-10-03 02:38:43 +00:00
Puyan Lotfi
406de17b9b [clang][ifs] Clang Interface Stubs ToolChain plumbing.
This patch enables end to end support for generating ELF interface stubs
directly from clang. Now the following:

clang -emit-interface-stubs -o libfoo.so a.cpp b.cpp c.cpp

will product an ELF binary with visible symbols populated. Visibility attributes
and -fvisibility can be used to control what gets populated.

* Adding ToolChain support for clang Driver IFS Merge Phase
* Implementing a default InterfaceStubs Merge clang Tool, used by ToolChain
* Adds support for the clang Driver to involve llvm-ifs on ifs files.
* Adds -emit-merged-ifs flag, to tell llvm-ifs to emit a merged ifs text file
  instead of the final object format (normally ELF)


Differential Revision: https://reviews.llvm.org/D63978

llvm-svn: 373538
2019-10-02 22:50:07 +00:00
Momchil Velikov
941660299a Enable memtag sanitizer in all AArch64 toolchains
That sanitizer does not have runtime library or other dependencies.

Differential Revision: https://reviews.llvm.org/D65642

llvm-svn: 368697
2019-08-13 14:20:23 +00:00
Shoaib Meenai
b50e8c5927 [Driver] Introduce -stdlib++-isystem
There are times when we wish to explicitly control the C++ standard
library search paths used by the driver. For example, when we're
building against the Android NDK, we might want to use the NDK's C++
headers (which have a custom inline namespace) even if we have C++
headers installed next to the driver. We might also be building against
a non-standard directory layout and wanting to specify the C++ standard
library include directories explicitly.

We could accomplish this by passing -nostdinc++ and adding an explicit
-isystem for our custom search directories. However, users of our
toolchain may themselves want to use -nostdinc++ and a custom C++ search
path (libc++'s build does this, for example), and our added -isystem
won't respect the -nostdinc++, leading to multiple C++ header
directories on the search path, which causes build failures.

Add a new driver option -stdlib++-isystem to support this use case.
Passing this option suppresses adding the default C++ library include
paths in the driver, and it also respects -nostdinc++ to allow users to
still override the C++ library paths themselves.

It's a bit unfortunate that we end up with both -stdlib++-isystem and
-cxx-isystem, but their semantics differ significantly. -cxx-isystem is
unaffected by -nostdinc++ and is added to the end of the search path
(which is not appropriate for C++ standard library headers, since they
often #include_next into other system headers), while -stdlib++-isystem
respects -nostdinc++, is added to the beginning of the search path, and
suppresses the default C++ library include paths.

Differential Revision: https://reviews.llvm.org/D64089

llvm-svn: 367982
2019-08-06 06:48:43 +00:00
Petr Hosek
08cb342afa [Driver] -noprofilelib flag
This flag is analoguous to other flags like -nostdlib or -nolibc
and could be used to disable linking of profile runtime library.
This is useful in certain environments like kernel, where profile
instrumentation is still desirable, but we cannot use the standard
runtime library.

llvm-svn: 365808
2019-07-11 19:06:38 +00:00
Fangrui Song
9c147bd40b [Driver] Add float-divide-by-zero back to supported sanitizers after D63793/rC365272
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
2019-07-10 00:30:02 +00:00
Petr Hosek
61a5e2833d [Driver] Change layout of per-target runtimes to resemble multiarch
This is a follow up to r361432, changing the layout of per-target
runtimes to more closely resemble multiarch. While before, we used
the following layout:

[RESOURCE_DIR]/<target>/lib/libclang_rt.<runtime>.<ext>

Now we use the following layout:

[RESOURCE_DIR]/lib/<target>/libclang_rt.<runtime>.<ext>

This also more closely resembles the existing "non-per-target" layout:

[RESOURCE_DIR]/lib/<os>/libclang_rt.<runtime>-<arch>.<ext>

This change will enable further simplification of the driver logic
in follow up changes.

Differential Revision: https://reviews.llvm.org/D62469

llvm-svn: 361784
2019-05-27 23:23:50 +00:00
Petr Hosek
2db79ef32c [Driver] Update handling of c++ and runtime directories
This is a follow up to r361432 and r361504 which addresses issues
introduced by those changes. Specifically, it avoids duplicating
file and runtime paths in case when the effective triple is the
same as the cannonical one. Furthermore, it fixes the broken multilib
setup in the Fuchsia driver and deduplicates some of the code.

Differential Revision: https://reviews.llvm.org/D62442

llvm-svn: 361709
2019-05-26 03:39:07 +00:00
Petr Hosek
762d008a7c [Driver] Try normalized triple when looking for C++ libraries
This addresses the issue introduced in r361432 where we would only
try effective triple but not the normalized one as we do for other
runtimes.

Differential Revision: https://reviews.llvm.org/D62286

llvm-svn: 361504
2019-05-23 15:23:16 +00:00
Petr Hosek
81f433b48c [runtimes] Move libunwind, libc++abi and libc++ to lib/$target/c++ and include/c++
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/$target/c++ and include/c++ directories, leaving resource directory
only for compiler-rt runtimes and Clang builtin headers.

Differential Revision: https://reviews.llvm.org/D59168

llvm-svn: 361432
2019-05-22 21:08:33 +00:00
Gheorghe-Teodor Bercea
e62c693c8e [OpenMP][Clang] Support for target math functions
Summary:
In this patch we propose a temporary solution to resolving math functions for the NVPTX toolchain, temporary until OpenMP variant is supported by Clang.

We intercept the inclusion of math.h and cmath headers and if we are in the OpenMP-NVPTX case, we re-use CUDA's math function resolution mechanism.

Authors:
@gtbercea
@jdoerfert

Reviewers: hfinkel, caomhin, ABataev, tra

Reviewed By: hfinkel, ABataev, tra

Subscribers: JDevlieghere, mgorny, guansong, cfe-commits, jdoerfert

Tags: #clang

Differential Revision: https://reviews.llvm.org/D61399

llvm-svn: 360265
2019-05-08 15:52:33 +00:00
Dan Albert
2715b28716 [Driver] Default Android toolchains to noexecstack.
Android does not support executable stacks.

Reviewers: srhines, pirama

Reviewed By: pirama

Subscribers: cfe-commits

Differential Revision: https://reviews.llvm.org/D53343

llvm-svn: 357197
2019-03-28 18:08:28 +00:00
Sterling Augustine
6271606969 Add --unwindlib=[libgcc|compiler-rt] to parallel --rtlib= [take 2]
"clang++ hello.cc --rtlib=compiler-rt"

now can works without specifying additional unwind or exception
handling libraries.

This reworked version of the feature no longer modifies today's default
unwind library for compiler-rt: which is nothing. Rather, a user
can specify -DCLANG_DEFAULT_UNWINDLIB=libunwind when configuring
the compiler.

This should address the issues from the previous version.

Update tests for new --unwindlib semantics.

Differential Revision: https://reviews.llvm.org/D59109

llvm-svn: 356508
2019-03-19 20:01:59 +00:00
Petr Hosek
930d46a2ef [Driver] Support object files in addition to static and shared libraries in compiler-rt
This change introduces support for object files in addition to static
and shared libraries which were already supported which requires
changing the type of the argument from boolean to an enum.

Differential Revision: https://reviews.llvm.org/D56044

llvm-svn: 355891
2019-03-12 02:12:48 +00:00
Matthew Voss
1262e52e16 Revert "[runtimes] Move libunwind, libc++abi and libc++ to lib/ and include/"
This broke the windows bots.

This reverts commit 28302c66d2.

llvm-svn: 355725
2019-03-08 20:33:55 +00:00
Petr Hosek
28302c66d2 [runtimes] Move libunwind, libc++abi and libc++ to lib/ and include/
This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory.  Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/<target> and include/ directories, leaving resource directory only
for compiler-rt runtimes and Clang builtin headers.

Differential Revision: https://reviews.llvm.org/D59013

llvm-svn: 355665
2019-03-08 05:35:22 +00:00
Manman Ren
394d4ccf69 Order File Instrumentation: add clang support for -forder-file-instrumentation
When -forder-file-instrumentation is on, we pass llvm flag to enable the order file instrumentation pass.

https://reviews.llvm.org/D58751

llvm-svn: 355333
2019-03-04 20:30:30 +00:00
Rong Xu
a4a09b2398 [PGO] Clang part of change for context-sensitive PGO (part1)
Part 1 of CSPGO change in Clang. This includes changes in clang options
and calls to llvm PassManager. Tests will be committed in part2.
This change needs the PassManager change in llvm.

Differential Revision: https://reviews.llvm.org/D54176

llvm-svn: 355331
2019-03-04 20:21:31 +00:00
Pierre Gousseau
ae5303d010 [Driver] Allow enum SanitizerOrdinal to represent more than 64 different sanitizer checks, NFC.
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".

This is a recommit of r354873 but with a fix for unqualified lookup error in lldb cmake build bot.

Fixes: https://llvm.org/PR39425

Differential Revision: https://reviews.llvm.org/D57914

llvm-svn: 355190
2019-03-01 10:05:15 +00:00
Pierre Gousseau
40ad3d2aa4 revert r354873 as this breaks lldb builds.
llvm-svn: 354875
2019-02-26 13:50:29 +00:00
Pierre Gousseau
44fad947a5 [Driver] Allow enum SanitizerOrdinal to represent more than 64 different sanitizer checks, NFC.
enum SanitizerOrdinal has reached maximum capacity, this change extends the capacity to 128 sanitizer checks.
This can eventually allow us to add gcc 8's options "-fsanitize=pointer-substract" and "-fsanitize=pointer-compare".

Fixes: https://llvm.org/PR39425

Differential Revision: https://reviews.llvm.org/D57914

llvm-svn: 354873
2019-02-26 13:30:14 +00:00
Sterling Augustine
5be3dbdb08 Rollback unwindlib patch.
llvm-svn: 352524
2019-01-29 18:27:51 +00:00
Sterling Augustine
9490fcc191 Add --unwindlib=[libgcc|compiler-rt] to parallel --rtlib=
Summary:
"clang++ hello.cc --rtlib=compiler-rt"

now works without specifying additional unwind or exception
handling libraries.

Reviewers: rsmith

Subscribers: srhines, dberris, aheejin, llvm-commits

Differential Revision: https://reviews.llvm.org/D57128

llvm-svn: 352404
2019-01-28 18:56:43 +00:00
Chandler Carruth
2946cd7010 Update the file headers across all of the LLVM projects in the monorepo
to reflect the new license.

We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.

Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.

llvm-svn: 351636
2019-01-19 08:50:56 +00:00
Raphael Isemann
b23ccecbb0 Misc typos fixes in ./lib folder
Summary: Found via `codespell -q 3 -I ../clang-whitelist.txt -L uint,importd,crasher,gonna,cant,ue,ons,orign,ned`

Reviewers: teemperor

Reviewed By: teemperor

Subscribers: teemperor, jholewinski, jvesely, nhaehnle, whisperity, jfb, cfe-commits

Differential Revision: https://reviews.llvm.org/D55475

llvm-svn: 348755
2018-12-10 12:37:46 +00:00
Vedant Kumar
6b062cd694 [gcov/Darwin] Ensure external symbols are exported when using an export list
Make sure that symbols needed to implement runtime support for gcov are
exported when using an export list on Darwin.

Without the clang driver exporting these symbols, the linker hides them,
resulting in tapi verification failures.

rdar://45944768

Differential Revision: https://reviews.llvm.org/D55151

llvm-svn: 348187
2018-12-03 20:53:58 +00:00
Martin Storsjo
b547ef2a29 Revert "Reapply: [Driver] Use forward slashes in most linker arguments"
This reverts commit r345370, as it uncovered even more issues in
tests with partial/inconsistent path normalization:
http://lab.llvm.org:8011/builders/llvm-clang-x86_64-expensive-checks-win/builds/13562
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/886
http://lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/20994

In particular, these tests seem to have failed:
    Clang :: CodeGen/thinlto-diagnostic-handler-remarks-with-hotness.ll
    Clang :: CodeGen/thinlto-multi-module.ll
    Clang :: Driver/cuda-external-tools.cu
    Clang :: Driver/cuda-options.cu
    Clang :: Driver/hip-toolchain-no-rdc.hip
    Clang :: Driver/hip-toolchain-rdc.hip
    Clang :: Driver/openmp-offload-gpu.c

At least the Driver tests could potentially be fixed by extending
the path normalization to even more places, but the issues with the
CodeGen tests are still unknown.

In addition, a number of other tests seem to have been broken in
other clang dependent tools such as clang-tidy and clangd.

llvm-svn: 345372
2018-10-26 08:33:29 +00:00
Martin Storsjo
cbd73574e4 Reapply: [Driver] Use forward slashes in most linker arguments
libtool inspects the output of $CC -v to detect what object files and
libraries are linked in by default. When clang is built as a native
windows executable, all paths are formatted with backslashes, and
the backslashes cause each argument to be enclosed in quotes. The
backslashes and quotes break further processing within libtool (which
is implemented in shell script, running in e.g. msys) pretty badly.

Between unix style pathes (that only work in tools that are linked
to the msys runtime, essentially the same as cygwin) and proper windows
style paths (with backslashes, that can easily break shell scripts
and msys environments), the best compromise is to use windows style
paths (starting with e.g. c:) but with forward slashes, which both
msys based tools, shell scripts and native windows executables can
cope with. This incidentally turns out to be the form of paths that
GCC prints out when run with -v on windows as well.

This change potentially makes the output from clang -v a bit more
inconsistent, but it is isn't necessarily very consistent to begin with.

Compared to the previous attempt in SVN r345004, this now does
the same transformation on more paths, hopefully on the right set
of paths so that all tests pass (previously some tests failed, where
path fragments that were required to be identical turned out to
use different path separators in different places). This now also
is done only for non-windows, or cygwin/mingw targets, to preserve
all backslashes for MSVC cases (where the paths can end up e.g. embedded
into PDB files. (The transformation function itself,
llvm::sys::path::convert_to_slash only has an effect when run on windows.)

Differential Revision: https://reviews.llvm.org/D53066

llvm-svn: 345370
2018-10-26 07:01:59 +00:00
Martin Storsjo
e133c7867e Revert "[Driver] Use forward slashes in most linker arguments"
This reverts commit r345004, as it broke tests when actually run
on windows; see e.g.
http://lab.llvm.org:8011/builders/clang-x64-windows-msvc/builds/763.

This broke tests that had captured a variable containing a path
with backslashes, which failed to match cases in the output
where the path separators had been changed into forward slashes.

llvm-svn: 345005
2018-10-23 07:01:55 +00:00
Martin Storsjo
965a361f57 [Driver] Use forward slashes in most linker arguments
libtool inspects the output of $CC -v to detect what object files and
libraries are linked in by default. When clang is built as a native
windows executable, all paths are formatted with backslashes, and
the backslashes cause each argument to be enclosed in quotes. The
backslashes and quotes break further processing within libtool (which
is implemented in shell script, running in e.g. msys) pretty badly.

Between unix style pathes (that only work in tools that are linked
to the msys runtime, essentially the same as cygwin) and proper windows
style paths (with backslashes, that can easily break shell scripts
and msys environments), the best compromise is to use windows style
paths (starting with e.g. c:) but with forward slashes, which both
msys based tools, shell scripts and native windows executables can
cope with. This incidentally turns out to be the form of paths that
GCC prints out when run with -v on windows as well.

This change potentially makes the output from clang -v a bit more
inconsistent, but it is isn't necessarily very consistent to begin with.

Differential Revision: https://reviews.llvm.org/D53066

llvm-svn: 345004
2018-10-23 06:33:26 +00:00
Jonas Devlieghere
fc51490baf Lift VFS from clang to llvm (NFC)
This patch moves the virtual file system form clang to llvm so it can be
used by more projects.

Concretely the patch:
 - Moves VirtualFileSystem.{h|cpp} from clang/Basic to llvm/Support.
 - Moves the corresponding unit test from clang to llvm.
 - Moves the vfs namespace from clang::vfs to llvm::vfs.
 - Formats the lines affected by this change, mostly this is the result of
   the added llvm namespace.

RFC on the mailing list:
http://lists.llvm.org/pipermail/llvm-dev/2018-October/126657.html

Differential revision: https://reviews.llvm.org/D52783

llvm-svn: 344140
2018-10-10 13:27:25 +00:00
Martin Storsjo
f32a0fc80d [MinGW] Allow using ASan
Linking to ASan for MinGW is similar to MSVC, but MinGW always links
the MSVCRT dynamically, so there is only one of the MSVC cases to
consider.

When linking to a shared compiler runtime library on MinGW, the suffix
of the import library is .dll.a.

The existing case of .dll as suffix for windows in general doesn't
seem correct (since this is used for linking). As long as callers never
actually set the Shared flag, the default static suffix of .lib also
worked fine for import libraries as well.

Differential Revision: https://reviews.llvm.org/D52538

llvm-svn: 343537
2018-10-01 20:53:25 +00:00
Richard Smith
cd35eff395 [modules] Driver support for precompiling a collection of files as a single
action.

llvm-svn: 342305
2018-09-15 01:21:16 +00:00
Petr Hosek
678c1c6ccc [Driver] Check normalized triples for multiarch runtime path
Previously we only used target triple as provided which matches the
GCC behavior, but it also means that all clients have to be consistent
in their spelling of target triples since e.g. x86_64-linux-gnu and
x86_64-unknown-linux-gnu will result in Clang driver looking at two
different paths when searching for runtime libraries.

Unfortunatelly, as it turned out many clients aren't consistent in
their spelling of target triples, e.g. many Linux distributions use
the shorter spelling but config.guess and rustc insist on using the
normalized variant which is causing issues. To avoid having to ship
multiple copies of runtimes for different triple spelling or rely on
symlinks which are not portable, we should also check the normalized
triple when constructing paths for multiarch runtimes.

Differential Revision: https://reviews.llvm.org/D50547

llvm-svn: 340471
2018-08-22 22:56:46 +00:00
Fangrui Song
6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Roman Lebedev
b69ba22773 [clang][ubsan] Implicit Conversion Sanitizer - integer truncation - clang part
Summary:
C and C++ are interesting languages. They are statically typed, but weakly.
The implicit conversions are allowed. This is nice, allows to write code
while balancing between getting drowned in everything being convertible,
and nothing being convertible. As usual, this comes with a price:

```
unsigned char store = 0;

bool consume(unsigned int val);

void test(unsigned long val) {
  if (consume(val)) {
    // the 'val' is `unsigned long`, but `consume()` takes `unsigned int`.
    // If their bit widths are different on this platform, the implicit
    // truncation happens. And if that `unsigned long` had a value bigger
    // than UINT_MAX, then you may or may not have a bug.

    // Similarly, integer addition happens on `int`s, so `store` will
    // be promoted to an `int`, the sum calculated (0+768=768),
    // and the result demoted to `unsigned char`, and stored to `store`.
    // In this case, the `store` will still be 0. Again, not always intended.
    store = store + 768; // before addition, 'store' was promoted to int.
  }

  // But yes, sometimes this is intentional.
  // You can either make the conversion explicit
  (void)consume((unsigned int)val);
  // or mask the value so no bits will be *implicitly* lost.
  (void)consume((~((unsigned int)0)) & val);
}
```

Yes, there is a `-Wconversion`` diagnostic group, but first, it is kinda
noisy, since it warns on everything (unlike sanitizers, warning on an
actual issues), and second, there are cases where it does **not** warn.
So a Sanitizer is needed. I don't have any motivational numbers, but i know
i had this kind of problem 10-20 times, and it was never easy to track down.

The logic to detect whether an truncation has happened is pretty simple
if you think about it - https://godbolt.org/g/NEzXbb - basically, just
extend (using the new, not original!, signedness) the 'truncated' value
back to it's original width, and equality-compare it with the original value.

The most non-trivial thing here is the logic to detect whether this
`ImplicitCastExpr` AST node is **actually** an implicit conversion, //or//
part of an explicit cast. Because the explicit casts are modeled as an outer
`ExplicitCastExpr` with some `ImplicitCastExpr`'s as **direct** children.
https://godbolt.org/g/eE1GkJ

Nowadays, we can just use the new `part_of_explicit_cast` flag, which is set
on all the implicitly-added `ImplicitCastExpr`'s of an `ExplicitCastExpr`.
So if that flag is **not** set, then it is an actual implicit conversion.

As you may have noted, this isn't just named `-fsanitize=implicit-integer-truncation`.
There are potentially some more implicit conversions to be warned about.
Namely, implicit conversions that result in sign change; implicit conversion
between different floating point types, or between fp and an integer,
when again, that conversion is lossy.

One thing i know isn't handled is bitfields.

This is a clang part.
The compiler-rt part is D48959.

Fixes [[ https://bugs.llvm.org/show_bug.cgi?id=21530 | PR21530 ]], [[ https://bugs.llvm.org/show_bug.cgi?id=37552 | PR37552 ]], [[ https://bugs.llvm.org/show_bug.cgi?id=35409 | PR35409 ]].
Partially fixes [[ https://bugs.llvm.org/show_bug.cgi?id=9821 | PR9821 ]].
Fixes https://github.com/google/sanitizers/issues/940. (other than sign-changing implicit conversions)

Reviewers: rjmccall, rsmith, samsonov, pcc, vsk, eugenis, efriedma, kcc, erichkeane

Reviewed By: rsmith, vsk, erichkeane

Subscribers: erichkeane, klimek, #sanitizers, aaron.ballman, RKSimon, dtzWill, filcab, danielaustin, ygribov, dvyukov, milianw, mclow.lists, cfe-commits, regehr

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D48958

llvm-svn: 338288
2018-07-30 18:58:30 +00:00
Petr Hosek
887f26d470 Support for multiarch runtimes layout
This change adds a support for multiarch style runtimes layout, so in
addition to the existing layout where runtimes get installed to:

lib/clang/$version/lib/$os

Clang now allows runtimes to be installed to:

lib/clang/$version/$target/lib

This also includes libc++, libc++abi and libunwind; today those are
assumed to be in Clang library directory built for host, with the
new layout it is possible to install libc++, libc++abi and libunwind
into the runtime directory built for different targets.

The use of new layout is enabled by setting the
LLVM_ENABLE_RUNTIME_TARGET_DIR CMake variable and is supported by both
projects and runtimes layouts. The runtimes CMake build has been further
modified to use the new layout when building runtimes for multiple
targets.

Differential Revision: https://reviews.llvm.org/D45604

llvm-svn: 335809
2018-06-28 03:11:52 +00:00
Pavel Labath
d8c6290ba4 Move VersionTuple from clang/Basic to llvm/Support
Summary:
This kind of functionality is useful to other project apart from clang.
LLDB works with version numbers a lot, but it does not have a convenient
abstraction for this. Moving this class to a lower level library allows
it to be freely used within LLDB.

Since this class is used in a lot of places in clang, and it used to be
in the clang namespace, it seemed appropriate to add it to the list of
adopted classes in LLVM.h to avoid prefixing all uses with "llvm::".

Also, I didn't find any tests specific for this class, so I wrote a
couple of quick ones for the more interesting bits of functionality.

Reviewers: zturner, erik.pilkington

Subscribers: mgorny, cfe-commits, llvm-commits

Differential Revision: https://reviews.llvm.org/D47887

llvm-svn: 334399
2018-06-11 10:28:04 +00:00
Shoaib Meenai
09edbddee7 [Driver] Stop passing -fseh-exceptions for x86_64-windows-msvc
-fseh-exceptions is only meaningful for MinGW targets, and that driver
already has logic to pass either -fdwarf-exceptions or -fseh-exceptions
as appropriate. -fseh-exceptions is just a no-op for MSVC triples, and
passing it to cc1 causes unnecessary confusion.

Differential Revision: https://reviews.llvm.org/D47850

llvm-svn: 334145
2018-06-06 23:09:02 +00:00
Sunil Srivastava
2ada2499ea Do not enable RTTI with -fexceptions, for PS4
NFC for targets other than PS4.

This patch is a change in behavior for PS4, in that PS4 will no longer enable
RTTI when -fexceptions is specified (RTTI and Exceptions are disabled by default
on PS4). RTTI will remain disabled except for types being thrown or caught.
Also, '-fexceptions -fno-rtti' (previously prohibited on PS4) is now accepted,
as it is for other targets.

This patch removes some PS4 specific code, making the code cleaner.

Also, in the test file rtti-options.cpp, PS4 tests where the behavior is the
same as the generic x86_64-linux are removed, making the test cleaner.

Differential Revision: https://reviews.llvm.org/D46982

llvm-svn: 332784
2018-05-18 23:32:01 +00:00
Adrian Prantl
9fc8faf9e6 Remove \brief commands from doxygen comments.
This is similar to the LLVM change https://reviews.llvm.org/D46290.

We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.

Patch produced by

for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done

Differential Revision: https://reviews.llvm.org/D46320

llvm-svn: 331834
2018-05-09 01:00:01 +00:00
Nico Weber
1865df4996 s/LLVM_ON_WIN32/_WIN32/, clang
LLVM_ON_WIN32 is set exactly with MSVC and MinGW (but not Cygwin) in
HandleLLVMOptions.cmake, which is where _WIN32 defined too.  Just use the
default macro instead of a reinvented one.

See thread "Replacing LLVM_ON_WIN32 with just _WIN32" on llvm-dev and cfe-dev.
No intended behavior change.

llvm-svn: 331069
2018-04-27 19:11:14 +00:00
Peter Collingbourne
f11eb3ebe7 AArch64: Implement support for the shadowcallstack attribute.
The implementation of shadow call stack on aarch64 is quite different to
the implementation on x86_64. Instead of reserving a segment register for
the shadow call stack, we reserve the platform register, x18. Any function
that spills lr to sp also spills it to the shadow call stack, a pointer to
which is stored in x18.

Differential Revision: https://reviews.llvm.org/D45239

llvm-svn: 329236
2018-04-04 21:55:44 +00:00