8248 Commits

Author SHA1 Message Date
Fangrui Song
d40fc6019b [sanitizer_common] Use O_TRUNC for WrOnly access mode.
Summary: Otherwise if the file existed and was larger than the write size before the OpenFile call, the file will not be truncated and contain garbage in trailing bytes.

Reviewers: glider, kcc, vitalybuka

Subscribers: kubamracek, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D48250

llvm-svn: 334881
2018-06-16 03:32:59 +00:00
Petr Hosek
5e6bc090ed [Fuzzer] Don't hardcode target architecture for Fuzzer tests
Don't hardcode the architecture for Fuzzer tests which breaks when
compiler-rt is being compiled for architectures other than x86_64.

Differential Revision: https://reviews.llvm.org/D48207

llvm-svn: 334852
2018-06-15 18:21:02 +00:00
Kostya Kortchinsky
4adf24502e [scudo] Add verbose failures in place of CHECK(0)
Summary:
The current `FailureHandler` mechanism was fairly opaque with regard to the
failure reason due to using `CHECK(0)`. Scudo is a bit different from the other
Sanitizers as it prefers to avoid spurious processing in its failure path. So
we just `dieWithMessage` using a somewhat explicit string.

Adapted the tests for the new strings.

While this takes care of the `OnBadRequest` & `OnOOM` failures, the next step
is probably to migrate the other Scudo failures in the same failes (header
corruption, invalid state and so on).

Reviewers: alekseyshl

Reviewed By: alekseyshl

Subscribers: filcab, mgorny, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48199

llvm-svn: 334843
2018-06-15 16:45:19 +00:00
Eli Friedman
16c4456022 [compiler-rt] [builtins] Don't build __atomic_* by default.
The locks need to be implemented in a shared library to work correctly,
so they shouldn't be part of libclang_rt.builtins.a, except in
specialized scenarios where the user can prove it will only be linked
once.

Differential Revision: https://reviews.llvm.org/D47606

llvm-svn: 334779
2018-06-14 23:22:53 +00:00
George Karpenkov
d1e0365ce3 [libFuzzer] [NFC] Support multi-arch and multi-OS building and testing
Differential Revision: https://reviews.llvm.org/D47296

llvm-svn: 334768
2018-06-14 20:46:07 +00:00
Alex Shlyapnikov
c9b41354ff [MSan] Linker-initialize static fallback_mutex in msan_allocator.cc
Summary:
static fallback_mutex in msan_allocator.cc does not need the ctor
call and can be linker initialized.

Issue: https://github.com/google/sanitizers/issues/194

Reviewers: morehouse, eugenis

Subscribers: delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48145

llvm-svn: 334749
2018-06-14 18:30:51 +00:00
Alex Shlyapnikov
241b758690 [ASan] Linker-initialize static ScopedInErrorReport::current_error_.
Summary:
Static ScopedInErrorReport::current_error_ can be linker initialized to
shave one global ctor call on application startup and be __asan_init-safe.

Global constructors in ASan runtime are bad because __asan_init runs
from preinit_array, before any such constructors.

Issue: https://github.com/google/sanitizers/issues/194

Reviewers: eugenis, morehouse

Subscribers: kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48141

llvm-svn: 334748
2018-06-14 18:22:23 +00:00
Peter Wu
4ff2d87f30 [ASAN] fix typos and disable long-object-path test for win32
Glob patterns seem unsupported for commands executed by the emulated
shell (LIT_USE_INTERNAL_SHELL=1). Disable the test while that is being
addressed (a workaround such as "cd a-*" also does not work).

llvm-svn: 334719
2018-06-14 15:12:46 +00:00
Kostya Kortchinsky
1ee741bdb6 [scudo] Make Secondary linker-initialized compliant
Summary:
As a follow up to D48142 for Scudo, switch the `SpinMutex` to its static
counterpart, and ensure zero-initialization by memset'ing the whole class.

Reviewers: alekseyshl

Reviewed By: alekseyshl

Subscribers: delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48148

llvm-svn: 334716
2018-06-14 14:33:28 +00:00
Peter Wu
1bbab1e558 [ASAN] fix startup crash in dlsym for long paths since glibc 2.27
Summary:
Error messages for dlsym used to be stored on the stack, but since
commit 2449ae7b ("ld.so: Introduce struct dl_exception") in glibc 2.27
these are now stored on the heap (and thus use the dlsym alloc pool).

Messages look like "undefined symbol: __isoc99_printf\0/path/to/a.out".
With many missing library functions and long object paths, the pool is
quickly exhausted. Implement a simple mechanism to return freed memory
to the pool (clear it in case it is used for calloc).

Fixes https://github.com/google/sanitizers/issues/957

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D47995

llvm-svn: 334703
2018-06-14 10:42:54 +00:00
David Carlier
706ea47bdc [Sanitizer] fix compilation warning
In most of systems, this field is a signed type but in some it is an unsigned.

Reviewers: vitalybuka

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D48118

llvm-svn: 334686
2018-06-14 04:51:26 +00:00
Peter Wu
0569660af3 [ASAN] Fix fputs interception for 32-bit macOS
On 32-bit macOS, "_fputs$UNIX2003" is called instead of "fputs" and the
"fgets_fputs" test fails. Apparently previous versions still passed the
test due to the internal implementation calling "strlen", but that does
not seem to be the case with macOS 10.13.3. Fixes r334450.

llvm-svn: 334670
2018-06-13 23:19:21 +00:00
Alex Shlyapnikov
3fc66075c7 [Sanitizers] Make sanitizer allocator linker-initialize compliant.
Summary:
These four SpinMutex ctors was the only code executed in the ctor for
the static __asan::Allocator instance (same for the other sanitizers
allocators), which is supposed to be fully linker-initialized.

Also, when the global ctor for this allocator instance is executed,
this instance might already be initialized by __asan_init called from
.preinit_array.

Issue: https://github.com/google/sanitizers/issues/194

Reviewers: morehouse, eugenis, cryptoad

Subscribers: kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48142

llvm-svn: 334660
2018-06-13 21:45:01 +00:00
Dimitry Andric
a00c372cd3 Disable MSan tests of prlimit on FreeBSD
Like NetBSD, FreeBSD does not have prlimit(2), so do not attempt to use
it during the MSan tests.

llvm-svn: 334659
2018-06-13 21:37:49 +00:00
Alex Shlyapnikov
4bf9b5612a [TSan] Fix madvise(MADV_NOHUGEPAGE) for meta shadow memory
Summary:
Move madvise(MADV_NOHUGEPAGE) for the meta shadow memory after the meta
shadow memory is mapped (currently it silently fails with ENOMEM).

Add a diagnostic message to detect similar problems in the future.

Reviewers: dvyukov

Subscribers: kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48097

llvm-svn: 334624
2018-06-13 17:18:41 +00:00
Petr Hosek
7252e2a8bd [XRay] Set an explicit dependency on libc++ when needed
When XRay is being built as part of the just built compiler together
with libc++ as part of the runtimes build, we need an explicit
dependency from XRay to libc++ to make sure that the library is
available by the time we start building XRay.

Differential Revision: https://reviews.llvm.org/D48113

llvm-svn: 334575
2018-06-13 07:08:28 +00:00
Petr Hosek
22f8825dca Reland "Passthrough additional flags to custom libcxx CMake build"
This is needed when we're cross-compiling compiler-rt.

Differential Revision: https://reviews.llvm.org/D47834

llvm-svn: 334570
2018-06-13 05:32:22 +00:00
Matt Morehouse
e3300d2ff3 Revert r334458, r334220, r334212, r334139.
Reverts changes to AddCompilerRT.cmake due to breakage of
http://lab.llvm.org:8011/builders/sanitizer-x86_64-linux/.

llvm-svn: 334528
2018-06-12 19:43:40 +00:00
Walter Lee
0a58f9c953 [asan, myriad] Support environment variables
Provide a buffer that the test harness can write into to provide
values for the environment variables.  Format is a null-separated list
of VAR=value pairs; this is sufficent for our purpose.

Differential Revision: https://reviews.llvm.org/D47960

llvm-svn: 334522
2018-06-12 18:34:12 +00:00
David Carlier
301855fb0d [Fuzzer] Afl driver changing iterations handling
Handling differently the iterations with the type limit and eventually an error message.

Reviewers: morehouse, kcc

Reviewed By: morehouse

Differential Revision: https://reviews.llvm.org/D47880

llvm-svn: 334510
2018-06-12 15:47:58 +00:00
Kostya Kortchinsky
76969eaf3d [scudo] Add C++17 aligned new/delete operators support
Summary:
This CL adds support for aligned new/delete operators (C++17). Currently we
do not support alignment inconsistency detection on deallocation, as this
requires a header change, but the APIs are introduced and are functional.

Add a smoke test for the aligned version of the operators.

Reviewers: alekseyshl

Reviewed By: alekseyshl

Subscribers: delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D48031

llvm-svn: 334505
2018-06-12 14:42:40 +00:00
Dean Michael Berris
aea8ece102 [XRay][profiler] Part 5: Profiler File Writing
Summary:
This is part of the larger XRay Profiling Mode effort.

This patch implements the profile writing mechanism, to allow profiles
collected through the profiler mode to be persisted to files.

Follow-on patches would allow us to load these profiles and start
converting/analysing them through the `llvm-xray` tool.

Depends on D44620.

Reviewers: echristo, kpw, pelikan

Reviewed By: kpw

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45998

llvm-svn: 334472
2018-06-12 04:06:25 +00:00
Dean Michael Berris
cfd7eec3d8 [XRay][profiler] Part 4: Profiler Mode Wiring
Summary:
This is part of the larger XRay Profiling Mode effort.

This patch implements the wiring required to enable us to actually
select the `xray-profiling` mode, and install the handlers to start
measuring the time and frequency of the function calls in call stacks.
The current way to get the profile information is by working with the
XRay API to `__xray_process_buffers(...)`.

In subsequent changes we'll implement profile saving to files, similar
to how the FDR and basic modes operate, as well as means for converting
this format into those that can be loaded/visualised as flame graphs. We
will also be extending the accounting tool in LLVM to support
stack-based function call accounting.

We also continue with the implementation to support building small
histograms of latencies for the `FunctionCallTrie::Node` type, to allow
us to actually approximate the distribution of latencies per function.

Depends on D45758 and D46998.

Reviewers: eizan, kpw, pelikan

Reviewed By: kpw

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D44620

llvm-svn: 334469
2018-06-12 03:29:39 +00:00
Ryan Prichard
1e216a59f6 [builtins] Delay emutls deallocation for one round
Summary:
With Android/Bionic, delay deallocation to round 2 of 4. It must run after
C++ thread_local destructors have been called, but before the final 2
rounds, because emutls calls free, and jemalloc then needs another 2
rounds to free its thread-specific data.

Fixes https://github.com/android-ndk/ndk/issues/687

Reviewers: cmtice, srhines, jyknight, chh, echristo

Reviewed By: srhines, chh, echristo

Subscribers: echristo, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D46978

llvm-svn: 334463
2018-06-12 01:32:26 +00:00
Ryan Prichard
31e4a550a3 [builtins] emutls cleanup: determine header size using sizeof
Summary: Also add a few post-#else/#endif comments

Reviewers: echristo, srhines

Reviewed By: echristo

Subscribers: chh, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47861

llvm-svn: 334462
2018-06-12 01:32:25 +00:00
Peter Wu
1c05c95739 [sanitizer] Add fgets, fputs and puts into sanitizer_common
Summary:
Add fgets, fputs and puts to sanitizer_common. This adds ASAN coverage
for these functions, extends MSAN support from fgets to fputs/puts and
extends TSAN support from puts to fputs.

Fixes: https://github.com/google/sanitizers/issues/952

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D46545

llvm-svn: 334450
2018-06-11 22:58:04 +00:00
Alex Shlyapnikov
789494026e [Sanitizers] Move pvalloc overflow tests to common.
Summary:
Now all sanitizers with improved allocator error reporting are covered
by these common tests.

Also, add pvalloc-specific checks to LSan.

HWASan is not covered by sanitizer_common, hence its own pvalloc
and other allocator tests.

Reviewers: vitalybuka

Subscribers: srhines, kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D47970

llvm-svn: 334424
2018-06-11 17:33:53 +00:00
Kostya Kortchinsky
4410e2c43f [scudo] Improve the scalability of the shared TSD model
Summary:
The shared TSD model in its current form doesn't scale. Here is an example of
rpc2-benchmark (with default parameters, which is threading heavy) on a 72-core
machines (defaulting to a `CompactSizeClassMap` and no Quarantine):
- with tcmalloc: 337K reqs/sec, peak RSS of 338MB;
- with scudo (exclusive): 321K reqs/sec, peak RSS of 637MB;
- with scudo (shared): 241K reqs/sec, peak RSS of 324MB.

This isn't great, since the exclusive model uses a lot of memory, while the
shared model doesn't even come close to be competitive.

This is mostly due to the fact that we are consistently scanning the TSD pool
starting at index 0 for an available TSD, which can result in a lot of failed
lock attempts, and touching some memory that needs not be touched.

This CL attempts to make things better in most situations:
- first, use a thread local variable on Linux (intead of pthread APIs) to store
  the current TSD in the shared model;
- move the locking boolean out of the TSD: this allows the compiler to use a
  register and potentially optimize out a branch instead of reading it from the
  TSD everytime (we also save a tiny bit of memory per TSD);
- 64-bit atomic operations on 32-bit ARM platforms happen to be expensive: so
  store the `Precedence` in a `uptr` instead of a `u64`. We lose some
  nanoseconds of precision and we'll wrap around at some point, but the benefit
  is worth it;
- change a `CHECK` to a `DCHECK`: this should never happen, but if something is
  ever terribly wrong, we'll crash on a near null AV if the TSD happens to be
  null;
- based on an idea by dvyukov@, we are implementing a bound random scan for
  an available TSD. This requires computing the coprimes for the number of TSDs,
  and attempting to lock up to 4 TSDs in an random order before falling back to
  the current one. This is obviously slightly more expansive when we have just
  2 TSDs (barely noticeable) but is otherwise beneficial. The `Precedence` still
  basically corresponds to the moment of the first contention on a TSD. To seed
  on random choice, we use the precedence of the current TSD since it is very
  likely to be non-zero (since we are in the slow path after a failed `tryLock`)

With those modifications, the benchmark yields to:
- with scudo (shared): 330K reqs/sec, peak RSS of 327MB.

So the shared model for this specific situation not only becomes competitive but
outperforms the exclusive model. I experimented with some values greater than 4
for the number of TSDs to attempt to lock and it yielded a decrease in QPS. Just
sticking with the current TSD is also a tad slower. Numbers on platforms with
less cores (eg: Android) remain similar.

Reviewers: alekseyshl, dvyukov, javed.absar

Reviewed By: alekseyshl, dvyukov

Subscribers: srhines, kristof.beyls, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47289

llvm-svn: 334410
2018-06-11 14:50:31 +00:00
Peter Wu
1db004ebdd [ASAN] Fix crash on i?86-linux (32-bit) against glibc 2.27 and later
Summary:
Running sanitized 32-bit x86 programs on glibc 2.27 crashes at startup, with:

    ERROR: AddressSanitizer: SEGV on unknown address 0xf7a8a250 (pc 0xf7f807f4 bp 0xff969fc8 sp 0xff969f7c T16777215)
    The signal is caused by a WRITE memory access.
    #0 0xf7f807f3 in _dl_get_tls_static_info (/lib/ld-linux.so.2+0x127f3)
    #1 0xf7a92599  (/lib/libasan.so.5+0x112599)
    #2 0xf7a80737  (/lib/libasan.so.5+0x100737)
    #3 0xf7f7e14f in _dl_init (/lib/ld-linux.so.2+0x1014f)
    #4 0xf7f6eb49  (/lib/ld-linux.so.2+0xb49)

The problem is that glibc changed the calling convention for the GLIBC_PRIVATE
symbol that sanitizer uses (even when it should not, GLIBC_PRIVATE is exactly
for symbols that can change at any time, be removed etc.), see
https://sourceware.org/ml/libc-alpha/2017-08/msg00497.html

Fixes https://github.com/google/sanitizers/issues/954

Patch By: Jakub Jelinek

Reviewed By: vitalybuka, Lekensteyn

Differential Revison: https://reviews.llvm.org/D44623

llvm-svn: 334363
2018-06-10 11:17:47 +00:00
Alex Shlyapnikov
643600566d [MSan] Report proper error on allocator failures instead of CHECK(0)-ing
Summary:
Following up on and complementing D44404.

Currently many allocator specific errors (OOM, for example) are reported as
a text message and CHECK(0) termination, not stack, no details, not too
helpful nor informative. To improve the situation, detailed and
structured errors were defined and reported under the appropriate conditions.

Reviewers: eugenis

Subscribers: srhines, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D47793

llvm-svn: 334338
2018-06-08 23:31:42 +00:00
Walter Lee
5a780ee9a9 [asan, myriad] Use local pool for new/delete when ASan run-time is not up
This can happen on Myriad RTEMS so needs to be handled.

Differential Revision: https://reviews.llvm.org/D47916

llvm-svn: 334329
2018-06-08 21:49:38 +00:00
Alex Shlyapnikov
dcf0097962 [Sanitizers] Check alignment != 0 for aligned_alloc and posix_memalign
Summary:
Move the corresponding tests to the common folder (as all of the
sanitizer allocators will support this feature soon) and add the checks
specific to aligned_alloc to ASan and LSan allocators.

Reviewers: vitalybuka

Subscribers: srhines, kubamracek, delcypher, #sanitizers, llvm-commits

Differential Revision: https://reviews.llvm.org/D47924

llvm-svn: 334316
2018-06-08 20:40:35 +00:00
David Carlier
6dedf2b5d8 [Xray] logging forgotten header
pthread.h missing for pthread_key* functions.

Reviewers: dberris

Reviewed By: dberris

Differential Revison: https://reviews.llvm.org/D47933

llvm-svn: 334272
2018-06-08 08:42:37 +00:00
Dean Michael Berris
b81372b56b [XRay][compiler-rt] Cleanup some internal XRay utilities
This change uses 'const' for the retryingWriteAll(...) API and removes
unnecessary 'static' local variables in getting the temporary filename.

llvm-svn: 334267
2018-06-08 07:48:03 +00:00
Dean Michael Berris
af4d583ea8 [XRay][compiler-rt] Remove reliance on C++ ABI features
Summary:
This fixes http://llvm.org/PR32274.

This change adds a test to ensure that we're able to link XRay modes and
the runtime to binaries that don't need to depend on the C++ standard
library or a C++ ABI library. In particular, we ensure that this will work
with C programs compiled+linked with XRay.

To make the test pass, we need to change a few things in the XRay
runtime implementations to remove the reliance on C++ ABI features. In
particular, we change the thread-safe function-local-static
initialisation to use pthread_* instead of the C++ features that ensure
non-trivial thread-local/function-local-static initialisation.

Depends on D47696.

Reviewers: dblaikie, jfb, kpw, eizan

Reviewed By: kpw

Subscribers: echristo, eizan, kpw, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D46998

llvm-svn: 334262
2018-06-08 04:00:07 +00:00
Alex Shlyapnikov
af12729185 [HWASan] Report proper error on allocator failures instead of CHECK(0)-ing
Summary:
Currently many allocator specific errors (OOM, for example) are reported as
a text message and CHECK(0) termination, not stack, no details, not too
helpful nor informative. To improve the situation, detailed and
structured errors were defined and reported under the appropriate conditions.

Reviewers: eugenis

Subscribers: kubamracek, delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47798

llvm-svn: 334248
2018-06-07 23:33:33 +00:00
Kostya Serebryany
111d0b2aec [libFuzzer] When printing NEW_FUNC, use 1-base indexing.
Summary: Otherwise we print things like [0/1] which is visually confusing.

Reviewers: kcc

Reviewed By: kcc

Subscribers: delcypher, llvm-commits, #sanitizers

Differential Revision: https://reviews.llvm.org/D47837

llvm-svn: 334234
2018-06-07 21:15:24 +00:00
Douglas Yung
20fa3d2504 Silence a -Wconstant-logical-operand warning.
llvm-svn: 334214
2018-06-07 18:51:47 +00:00
Petr Hosek
157a5c2f09 [Fuzzer] Update the header path for fdio/spawn.h on Fuchsia
The path now includes lib/ prefix.

Differential Revision: https://reviews.llvm.org/D47866

llvm-svn: 334213
2018-06-07 18:41:35 +00:00
Kamil Rytarowski
b9c78e41ba Disable recursive interceptors in signal(3)/MSan
Summary:
signal(3) on NetBSD calls internally sigaction(2).

Without disabling the recursive interceptor, there are
false positives about uninitialized memory reads inside libc.

This change fixes execution of such programs as sh(1) and
vmstat(1) in the NetBSD userland.

Sponsored by <The NetBSD Foundation>

Reviewers: eugenis, vitalybuka, joerg

Reviewed By: vitalybuka

Subscribers: llvm-commits, #sanitizers

Tags: #sanitizers

Differential Revision: https://reviews.llvm.org/D47650

llvm-svn: 334168
2018-06-07 07:55:20 +00:00
Kostya Serebryany
67af99235f [libFuzzer] make the corpus elements aware of their data flow traces
llvm-svn: 334158
2018-06-07 01:40:20 +00:00
Vitaly Buka
661d81ef61 [sanitizer] Don't use internal_unlink on Windows
llvm-svn: 334152
2018-06-07 00:26:06 +00:00
Kostya Serebryany
4d9fd7a266 [libFuzzer] remove an experimental flag -use_feature_frequency
llvm-svn: 334146
2018-06-06 23:24:41 +00:00
Petr Hosek
3a32b41024 [Fuzzer] Use private libc++ even for Fuchsia
On Fuchsia, we use libc++ compiled with ASan for our ASan built
executable which means we cannot use the same libc++ for libFuzzer when
building fuzz targets, instead we'll link a custom internal libc++ into
Fuchsia's build of libFuzzer like we already do on Linux.

Differential Revision: https://reviews.llvm.org/D47835

llvm-svn: 334144
2018-06-06 22:59:14 +00:00
Petr Hosek
3cf6db2d56 [CMake] Passthrough additional flags to custom libcxx CMake build
This is needed when we're cross-compiling compiler-rt.

Differential Revision: https://reviews.llvm.org/D47834

llvm-svn: 334139
2018-06-06 22:10:12 +00:00
Vitaly Buka
72fd23c9c5 [sanitizer] Replace deprecated mktemp with mkstemp
llvm-svn: 334138
2018-06-06 22:05:48 +00:00
Vitaly Buka
4ef9117b49 [sanitizer] Cleanup ReadFileToVector and ReadFileToBuffer
Summary:
Added unit-test.
Fixed behavior of max_len argument.
Call read syscall with all available buffer, not just a page.

Reviewers: eugenis

Subscribers: kubamracek, mgorny, llvm-commits

Differential Revision: https://reviews.llvm.org/D46618

llvm-svn: 334130
2018-06-06 20:53:43 +00:00
Walter Lee
381072c417 [asan] Fix Myraid RTEMS port broken by r333985
Add nop CheckASLR() function.

llvm-svn: 334102
2018-06-06 15:39:47 +00:00
Ilya Biryukov
b7c3745006 Fix compile error with libstdc++.
By adding a ctor to create fuzzer_allocator<T> from fuzzer_allocator<U>.
This mimics construcotrs of std::allocator<T>.

Without the constructors, some versions of libstdc++ can't compile
`vector<bool, fuzzer_allocator<bool>>`.

llvm-svn: 334077
2018-06-06 09:22:19 +00:00
Dean Michael Berris
c561970b27 [XRay][compiler-rt] Refactor recursion guard for Basic and FDR Mode
Summary:
This change extracts the recursion guard implementation from FDR Mode
and updates it to do the following:

- Do the atomic operation correctly to be signal-handler safe.

- Make it usable in both FDR and Basic Modes.

Before this change, the recursion guard relied on an unsynchronised read
and write on a volatile thread-local. A signal handler could then run in
between the read and the write, and then be able to run instrumented
code as part of the signal handling. Using an atomic exchange instead
fixes that by doing a proper mutual exclusion even in the presence of
signal handling.

Reviewers: kpw, eizan, jfb

Reviewed By: eizan

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47696

llvm-svn: 334064
2018-06-06 06:07:48 +00:00