Summary:
Some time ago, the sanitizers as of r315899 were imported into gcc mainline. This broke
bootstrap on Darwin 10 and 11, as reported in GCC PR sanitizer/82824
(https://gcc.gnu.org/bugzilla/show_bug.cgi?id=82824) due to the unconditional use
of VM_MEMORY_OS_ALLOC_ONCE. This was only introduced in Darwin 13/Mac OS X 10.9.
The use of the macro was introduced in r300450.
I couldn't find any statement which Darwin versions are supposed to be supported by
LLVM, but the trivial patch to use the macro only if present allowed the gcc bootstrap
to finish.
So far, I haven't tried building llvm/compiler-rt on Darwin 11. Maybe the patch is
simple enough to go in nonetheless.
Committing on behalf of ro.
Reviewers: glider, fjricci, kcc, kuba, kubamracek, george.karpenkov
Reviewed By: fjricci
Subscribers: #sanitizers, zaks.anna, srhines, dberris, kubamracek, llvm-commits
Tags: #sanitizers
Differential Revision: https://reviews.llvm.org/D39888
llvm-svn: 322437
Summary:
__DATA segments on Darwin contain a large number of separate sections,
many of which cannot actually contain pointers, and contain const values or
objc metadata. Not scanning sections which cannot contain pointers significantly
improves performance.
On a medium-sized (~4000 files) internal project, I saw a speedup of about 30%
in standalone LSan's execution time (30% improvement in the time spent running
LSan, not the total program time).
Reviewers: kcc, kubamracek, alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35432
llvm-svn: 308999
Summary:
Calling exit() from an atexit handler is undefined behavior.
On Linux, it's unavoidable, since we cannot intercept exit (_exit isn't called
if a user program uses return instead of exit()), and I haven't
seen it cause issues regardless.
However, on Darwin, I have a fairly complex internal test that hangs roughly
once in every 300 runs after leak reporting finishes, which is resolved with
this patch, and is presumably due to the undefined behavior (since the Die() is
the only thing that happens after the end of leak reporting).
In addition, this is the way TSan works as well, where an atexit handler+Die()
is used on Linux, and an _exit() interceptor is used on Darwin. I'm not sure if it's
intentionally structured that way in TSan, since TSan sets up the atexit handler and the
_exit() interceptor on both platforms, but I have observed that on Darwin, only the
_exit() interceptor is used, and on Linux the atexit handler is used.
There is some additional related discussion here: https://reviews.llvm.org/D35085
Reviewers: alekseyshl, kubamracek
Subscribers: eugenis, vsk, llvm-commits
Differential Revision: https://reviews.llvm.org/D35513
llvm-svn: 308353
Summary:
__DATA segments on Darwin contain a large number of separate sections,
most of which cannot actually contain pointers, and contain const values or
objc metadata. Only scanning sections which can contain pointers greatly improves
performance.
On a medium-sized (~4000 files) internal project, I saw a speedup of about 50%
in standalone LSan's execution time (50% improvement in the time spent running
LSan, not the total program time).
Reviewers: kcc, kubamracek, alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D35432
llvm-svn: 308231
Summary:
This is the first in a series of patches to refactor sanitizer_procmaps
to allow MachO section information to be exposed on darwin.
In addition, grouping all segment information in a single struct is
cleaner than passing it through a large set of output parameters, and
avoids the need for annotations of NULL parameters for unneeded
information.
The filename string is optional and must be managed and supplied by the
calling function. This is to allow the MemoryMappedSegment struct to be
stored on the stack without causing overly large stack sizes.
Reviewers: alekseyshl, kubamracek, glider
Subscribers: emaste, llvm-commits
Differential Revision: https://reviews.llvm.org/D35135
llvm-svn: 307688
Summary:
This is required for standalone LSan to work with libdispatch worker threads,
and is a slimmed down version of the functionality provided for ASan
in asan_mac.cc.
Re-commit of r305695 with use_stacks=0 to get around a racy lingering pointer.
Reviewers: alekseyshl, kubamracek, glider, kcc
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D34247
llvm-svn: 305732
Summary:
This is required for standalone LSan to work with libdispatch worker threads,
and is a slimmed down version of the functionality provided for ASan
in asan_mac.cc.
Reviewers: alekseyshl, kubamracek, glider, kcc
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D34247
llvm-svn: 305695
Summary:
This required for any users who call exit() after creating
thread-specific data, as tls destructors are only called when
pthread_exit() or pthread_cancel() are used. This should also
match tls behavior on linux.
Getting the base address of the tls section is straightforward,
as it's stored as a section offset in %gs. The size is a bit trickier
to work out, as there doesn't appear to be any official documentation
or source code referring to it. The size used in this patch was determined
by taking the difference between the base address and the address of the
subsequent memory region returned by vm_region_recurse_64, which was
1024 * sizeof(uptr) on all threads except the main thread, where it was
larger. Since the section must be the same size on all of the threads,
1024 * sizeof(uptr) seemed to be a reasonable size to use, barring
a more programtic way to get the size.
1024 seems like a reasonable number, given that PTHREAD_KEYS_MAX
is 512 on darwin, so pthread keys will fit inside the region while
leaving space for other tls data. A larger size would overflow the
memory region returned by vm_region_recurse_64, and a smaller size
wouldn't leave room for all the pthread keys. In addition, the
stress test added here passes, which means that we are scanning at
least the full set of possible pthread keys, and probably
the full tls section.
Reviewers: alekseyshl, kubamracek
Subscribers: krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D33215
llvm-svn: 303887
Summary:
The LINKEDIT section is very large and is read-only. Scanning this
section caused LSan on darwin to be very slow. When only writable sections
are scanned for global pointers, performance improved by a factor of about 25x.
Reviewers: alekseyshl, kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D33322
llvm-svn: 303422
Summary:
This required for any users who call exit() after creating
thread-specific data, as tls destructors are only called when
pthread_exit() or pthread_cancel() are used. This should also
match tls behavior on linux.
Getting the base address of the tls section is straightforward,
as it's stored as a section offset in %gs. The size is a bit trickier
to work out, as there doesn't appear to be any official documentation
or source code referring to it. The size used in this patch was determined
by taking the difference between the base address and the address of the
subsequent memory region returned by vm_region_recurse_64, which was
1024 * sizeof(uptr) on all threads except the main thread, where it was
larger. Since the section must be the same size on all of the threads,
1024 * sizeof(uptr) seemed to be a reasonable size to use, barring
a more programtic way to get the size.
1024 seems like a reasonable number, given that PTHREAD_KEYS_MAX
is 512 on darwin, so pthread keys will fit inside the region while
leaving space for other tls data. A larger size would overflow the
memory region returned by vm_region_recurse_64, and a smaller size
wouldn't leave room for all the pthread keys. In addition, the
stress test added here passes, which means that we are scanning at
least the full set of possible pthread keys, and probably
the full tls section.
Reviewers: alekseyshl, kubamracek
Subscribers: krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D33215
llvm-svn: 303262
Summary: This should significantly improve darwin lsan performance in cases where root regions are not used.
Reviewers: alekseyshl, kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32966
llvm-svn: 302530
Summary:
In the general case, we only need to check for root regions inside
the memory map returned by procmaps. However, on Darwin,
we also need to check inside mmap'd regions, which aren't returned
in the list of modules we get from procmaps.
This patch refactors memory region scanning on darwin to reduce
code duplication with the kernel alloc once page scan.
Reviewers: kubamracek, alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32190
llvm-svn: 300760
Summary:
ProcessPlatformSpecificAllocations for linux leak sanitizer iterated over
memory chunks and ran two checks concurrently:
1) Ensured the pc was valid
2) Checked whether it was a linker allocation
All platforms will need the valid pc check, so it is moved out of the platform-
specific file. To prevent code and logic duplication, the linker allocation
check is moved as well, with the name of the linker supplied by the platform-specific
module. In cases where we don't need to check for linker allocations (ie Darwin),
this name will be a nullptr, and we'll only run the caller pc checks.
Reviewers: kubamracek, alekseyshl, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32130
llvm-svn: 300690
Summary: This specifically addresses the Mach-O zero page, which we cannot read from.
Reviewers: kubamracek, samsonov, alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32044
llvm-svn: 300456
Summary:
These checks appear linux-specific, disable them on darwin, at
least for now.
Reviewers: kubamracek, alekseyshl
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D32013
llvm-svn: 300248
Summary:
The routines for thread destruction in the thread registry require
the lsan thread index, which is stored in pthread tls on OS X.
This means that we need to make sure that the lsan tls isn't destroyed
until after the thread registry tls. This change ensures that we
don't delete the lsan tls until we've finished destroying the thread
in the registry, ensuring that the destructor for the lsan tls runs
after the destructor for the thread registry tls.
This patch also adds a check to ensure that the thread ID is valid before
returning it in GetThreadID(), to ensure that the above behavior
is working correctly.
Reviewers: dvyukov, kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31884
llvm-svn: 299978
Summary:
We currently don't have any platform specific darwin
lsan modules, don't force failure if they don't exist.
Reviewers: kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31473
llvm-svn: 299031
Summary:
This prevents InternalAlloc from being called before the sanitizers
are fully initialized.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31306
llvm-svn: 298947
Summary:
This patch allows us to move away from using __thread on darwin,
which is requiring for building lsan for darwin on ios version 7
and on iossim i386.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D31291
llvm-svn: 298848
Summary:
This patch allows us to move away from using __thread on darwin,
which is requiring for building lsan for darwin on ios version 7
and on iossim i386.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29994
llvm-svn: 298274
Summary:
This patch allows us to move away from using __thread on darwin,
which is requiring for building lsan for darwin on ios version 7
and on iossim i386.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29994
llvm-svn: 298214
Summary:
This patch allows us to move away from using __thread on darwin,
which is requiring for building lsan for darwin on ios version 7
and on iossim i386.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29994
llvm-svn: 296707
Summary:
This patch allows us to move away from using __thread on darwin,
which is requiring for building lsan for darwin on ios version 7
and on iossim i386.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29994
llvm-svn: 295413
Summary:
__thread is not supported by all darwin versions and architectures,
use pthreads instead to allow for building darwin lsan on iossim.
Reviewers: kubamracek, kcc
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29993
llvm-svn: 295405
Summary:
__thread is supported on Darwin, but is implemented dynamically via
function calls to __tls_get_addr. This causes two issues when combined
with leak sanitizer, due to malloc() interception.
- The dynamic loader calls malloc during the process of loading
the sanitizer dylib, while swapping a placeholder tlv_boostrap
function for __tls_get_addr. This will cause tlv_bootstrap to
be called in DisabledInThisThread() via the asan allocator.
- The first time __tls_get_addr is called, it allocates memory
for the thread-local object, during which it calls malloc(). This
call will be intercepted, leading to an infinite loop in the asan
allocator, in which the allocator calls DisabledInThisThread,
which calls tls_get_addr, which calls into the allocator again.
Reviewers: kcc, glider, kubamracek
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D29786
llvm-svn: 294994
Summary:
This patch provides stubs for all of the lsan platform-specific
functions which need to be implemented for darwin. Currently
all of these functions are stubs, for the purpose of fixing
compilation.
Reviewers: kcc, glider, kubamracek
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D29784
llvm-svn: 294983
Vitaly Buka