Commit Graph

4382 Commits

Author SHA1 Message Date
Hiroshi Inoue 9ff2380ea6 [NFC] fix trivial typos in comments and error message
"is is" -> "is", "are are" -> "are"

llvm-svn: 329546
2018-04-09 04:37:53 +00:00
Mandeep Singh Grang 68ab401f62 [Support] Change std::sort to llvm::sort in response to r327219
Summary:
r327219 added wrappers to std::sort which randomly shuffle the container before sorting.
This will help in uncovering non-determinism caused due to undefined sorting
order of objects having the same key.

To make use of that infrastructure we need to invoke llvm::sort instead of std::sort.

Note: This patch is one of a series of patches to replace *all* std::sort to llvm::sort.
Refer the comments section in D44363 for a list of all the required patches.

Reviewers: chandlerc, jordan_rose, bkramer

Reviewed By: bkramer

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45140

llvm-svn: 329536
2018-04-08 16:46:22 +00:00
Graydon Hoare 54fe208a5f [Support] Make line-number cache robust against access patterns.
Summary:
The LLVM SourceMgr class (which is used indirectly by Swift, though not Clang)
has a routine for looking up line numbers of SMLocs. This routine uses a
shared, special-purpose cache that handles exactly one access pattern
efficiently: looking up the line number of an SMLoc that points into the same
buffer as the last query made to the SourceMgr, at a location in the buffer at
or ahead of the last query.

When this works it's fine, but when it fails it's catastrophic for performancer:
one recent out-of-order access from a Swift utility routine ran for tens of
seconds, spending 99% of its time repeatedly scanning buffers for '\n'.

This change removes the shared cache from the SourceMgr and installs a new
cache in each SrcBuffer. The per-SrcBuffer caches are also "full", in the sense
that rather than caching a single last-query pointer, they cache _all_ the
line-ending offsets, in a binary-searchable array, such that once it's
populated (on first access), all subsequent access patterns run at the same
speed.

Performance measurements I've done show this is actually a little bit faster on
real codebases (though only a couple fractions of a percent). Memory usage is
up by a few tens to hundreds of bytes per SrcBuffer that has a line lookup done
on it; I've attempted to minimize this by using dynamic selection of integer
sized when storing offset arrays. But the main motive here is to
make-impossible the cases we don't always see, that show up by surprise when
there is an out-of-order access pattern.

Reviewers: jordan_rose

Reviewed By: jordan_rose

Subscribers: probinson, llvm-commits

Differential Revision: https://reviews.llvm.org/D45003

llvm-svn: 329470
2018-04-07 00:44:02 +00:00
Aaron Smith 8a5ea61886 Windows needs the current codepage instead of utf8 sometimes
Llvm-mc (and tools that use Path.inc on Windows) assume that strings are utf-8 
encoded, however, this is not always the case. On Windows the default codepage 
is not utf-8, so most of the time the strings are not utf-8 encoded.

The lld test 'format-binary-non-ascii' uses llvm-mc with a file with non-ascii 
characters in the name which is how this bug was found. The test fails when run 
using Python 3 because it uses properly encoded unicode strings (Python 2 actually 
ends up using a byte string which is not utf-8 encoded, so the test passes, but 
that's separate issue). 

Patch by Stella Stamenova!

llvm-svn: 329468
2018-04-07 00:32:59 +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
Nico Weber 868112181b Remove HAVE_LIBPSAPI, HAVE_SHELL32.
These used to be set in the old autoconf build, but the cmake build has had a
"TODO: actually check for these" comment since it was checked in, and they
were set to 1 on mingw unconditionally.  It seems safe to say that they always
exist under mingw, so just remove them and assume they're set exactly when on
mingw (with msvc, we use `pragma comment` instead of linking these via flags).

llvm-svn: 328992
2018-04-02 17:32:48 +00:00
Nico Weber f3db8e3c70 Remove HAVE_DIRENT_H.
The autoconf manual: "This macro is obsolescent, as all current systems with
directory libraries have <dirent.h>. New programs need not use this macro."

llvm-svn: 328989
2018-04-02 17:17:29 +00:00
Nico Weber 9f03e9de77 Remove HAVE_WRITEV that's unused after r255837.
llvm-svn: 328977
2018-04-02 14:18:13 +00:00
Nico Weber 2eada78a50 Attempt to heal bots after r328970.
llvm-svn: 328974
2018-04-02 13:49:35 +00:00
Craig Topper 8a1787ae22 [DebugCounter] Make -debug-counter cl::Hidden.
llvm-svn: 328948
2018-04-01 22:16:52 +00:00
Graydon Hoare 926cd9b837 [YAML] Escape non-printable multibyte UTF8 in Output::scalarString.
The existing YAML Output::scalarString code path includes a partial and
incorrect implementation of YAML escaping logic. In particular, the logic put
in place in rL321283 escapes non-printable bytes only if they are not part of a
multibyte UTF8 sequence; implicitly this means that all multibyte UTF8
sequences -- printable and non -- are passed through verbatim.

The simplest solution to this is to direct the Output::scalarString method to
use the standalone yaml::escape function, and this _almost_ works, except that
the existing code in that function _over_ escapes: any multibyte UTF8 sequence
is escaped, even printable ones. While this is permitted for YAML, it is also
more aggressive (and hard to read for non-English locales) than necessary,
and the entire point of rL321283 was to back off such aggressive over-escaping.

So in this change, I have both redirected Output::scalarString to use
yaml::escape _and_ modified yaml::escape to optionally restrict its escaping to
non-printables. This preserves behaviour of any existing clients while giving
them a path to more moderate escaping should they desire.

Reviewers: JDevlieghere, thegameg, MatzeB, vladimir.plyashkun

Reviewed By: thegameg

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44863

llvm-svn: 328661
2018-03-27 19:52:45 +00:00
Tony Tye 7a893d4e34 [AMDGPU] Remove use of OpenCL triple environment and replace with function attribute for AMDGPU
- Remove use of the opencl and amdopencl environment member of the target triple for the AMDGPU target.
- Use function attribute to communicate to the AMDGPU backend to add implicit arguments for OpenCL kernels for the AMDHSA OS.

Differential Revision: https://reviews.llvm.org/D43736

llvm-svn: 328349
2018-03-23 18:45:18 +00:00
Fangrui Song c244a15801 [ADT] Simplify getMemory. NFC
llvm-svn: 328334
2018-03-23 17:26:12 +00:00
Ilya Biryukov 8418576304 Changed createTemporaryFile without FD to actually create a file.
Summary:
This commit changes semantics of createUniqueFile and
createTemporaryFile variants that do not return file descriptors.
Previously they only checked if files exist, therefore being subject
to race conditions. Now they will create an empty file to avoid them.

Functions that do not create a file are now called
getPotentiallyUniqueTempFileName and getPotentiallyUniqueFileName.

Reviewers: klimek, bkramer, krasimir, JDevlieghere, espindola

Reviewed By: klimek

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D36827

llvm-svn: 327851
2018-03-19 14:19:58 +00:00
Jonas Devlieghere 2b8b90a768 Fix compilation on Darwin with expensive checks.
After r327219 was landed, the bot with expensive checks on GreenDragon
started failing. The problem was missing symbols `regex_t` and
`regmatch_t` in `xlocale/_regex.h`. The latter was included because
after the change in r327219, `random` is needed, which transitively
includes `xlocale.h.` which in turn conditionally includes
`xlocale/_regex.h` when _REGEX_H_ is defined. Because this is the header
guard in `regex_impl.h` and because `regex_impl.h` was included before
the other LLVM includes, `xlocale/_regex.h` was included without the
necessary types being available.

This commit fixes this by moving the include of `regex_impl.h` all the
way down. I also added a comment to stress the significance of its
position.

llvm-svn: 327256
2018-03-12 11:01:05 +00:00
Jonas Devlieghere 6921753994 [Support] Move syntax highlighting into support
Move the DWARF syntax highlighting into support. This has several
advantages, most notably that this makes the WithColor RAII wrapper
available outside libDebugInfo. Furthermore, several projects all have
their own code for handling colored output. This provides a place to
centralize it.

Differential revision: https://reviews.llvm.org/D44215

llvm-svn: 327108
2018-03-09 09:56:24 +00:00
Eric Christopher 3390a8f63d Fix header comment on SHA1 code.
llvm-svn: 327086
2018-03-09 00:23:35 +00:00
Zachary Turner 0f701c4a95 Fix signed-unsigned comparison warning.
llvm-svn: 327060
2018-03-08 20:57:37 +00:00
Zachary Turner adad33011f [Support] Add WriteThroughMemoryBuffer.
This is like MemoryBuffer (read-only) and WritableMemoryBuffer
(writable private), but where the underlying file can be modified
after writing.  This is useful when you want to open a file, make
some targeted edits, and then write it back out.

Differential Revision: https://reviews.llvm.org/D44230

llvm-svn: 327057
2018-03-08 20:34:47 +00:00
Daniel Sanders 1087a54255 Support resetting STATISTIC() values using llvm::ResetStatistics()
Summary:
Most of the time, compiler statistics can be obtained using a process that
performs a single compilation and terminates such as llc. However, this isn't
always the case. JITs for example, perform multiple compilations over their
lifetime and STATISTIC() will record cumulative values across all of them.

Provide tools like this with the facilities needed to measure individual
compilations by allowing them to reset the STATISTIC() values back to zero using
llvm::ResetStatistics(). It's still the tools responsibility to ensure that they
perform compilations in such a way that the results are meaningful to their
intended use.

Reviewers: qcolombet, rtereshin, bogner, aditya_nandakumar

Reviewed By: bogner

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44181

llvm-svn: 326981
2018-03-08 02:36:25 +00:00
Craig Topper 8665f59e2c [Support] Stop passing StringRefs by const reference in some of the getHostCPUname implementations. NFC
llvm-svn: 326916
2018-03-07 17:53:16 +00:00
Craig Topper 55ad3299d4 [X86] Fix a typo in Host.cpp that causes us to misidentify KNL, Silvermont, Goldmont and probably other CPUs for -march=native
I think most of the Intel Core CPUs and recent AMD CPUs are unaffected. All the CPUs that have a "subtype" should work. The ones that were broken are the ones that are a "type" with no subtypes.

Fixes PR36619.

llvm-svn: 326840
2018-03-06 22:45:31 +00:00
Daniel Sanders 0f4b015268 PrintStatistics() and PrintStatisticsJSON() should take StatLock
These two functions iterate over the list of statistics but don't take the lock
that protects the iterators from being invalidated by
StatisticInfo::addStatistic().

So far, this hasn't been an issue since (in-tree at least) these functions are
called by the StatisticInfo destructor so addStatistic() shouldn't be called
anymore. However, we do expose them in the public API.

Note that this only protects against iterator invalidation and does not protect
against ordering issues caused by statistic updates that race with
PrintStatistics()/PrintStatisticsJSON().

Thanks to Roman Tereshin for spotting it

llvm-svn: 326834
2018-03-06 21:16:42 +00:00
Tony Tye bf320ee335 [AMDGPU] Remove unused AMDOpenCL triple environment
Differential Revision: https://reviews.llvm.org/D43895

llvm-svn: 326745
2018-03-05 21:39:41 +00:00
Daniel Sanders a09751e779 Re-commit: Make STATISTIC() values available programmatically
Summary:
It can be useful for tools to be able to retrieve the values of variables
declared via STATISTIC() directly without having to emit them and parse
them back. Use cases include:
* Needing to report specific statistics to a test harness
* Wanting to post-process statistics. For example, to produce a percentage of
  functions that were fully selected by GlobalISel

Make this possible by adding llvm::GetStatistics() which returns an
iterator_range that can be used to inspect the statistics that have been
touched during execution. When statistics are disabled (NDEBUG and not
LLVM_ENABLE_STATISTICS) this method will return an empty range.

This patch doesn't address the effect of multiple compilations within the same
process. In such situations, the statistics will be cumulative for all
compilations up to the GetStatistics() call.

Reviewers: qcolombet, rtereshin, aditya_nandakumar, bogner

Reviewed By: rtereshin, bogner

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D43901

This re-commit fixes a missing include of <vector> which it seems clang didn't
mind but G++ and MSVC objected to. It seems that, clang was ok with std::vector
only being forward declared at the point of use since it was fully defined
eventually but G++/MSVC both rejected it at the point of use.

llvm-svn: 326738
2018-03-05 19:38:16 +00:00
Dmitry Mikulin 430c7ff732 On Windows we need to be able to process response files with Windows-style
path names.

Differential Revision: https://reviews.llvm.org/D43988

llvm-svn: 326737
2018-03-05 19:34:33 +00:00
Daniel Sanders 7612f85df5 Revert r326723: Make STATISTIC() values available programmatically
Despite building cleanly on my machine in three separate configs, it's failing on pretty much all bots due to missing includes among other things. Investigating.

llvm-svn: 326726
2018-03-05 17:52:43 +00:00
Daniel Sanders edcf110b23 Make STATISTIC() values available programmatically
Summary:
It can be useful for tools to be able to retrieve the values of variables
declared via STATISTIC() directly without having to emit them and parse
them back. Use cases include:
* Needing to report specific statistics to a test harness
* Wanting to post-process statistics. For example, to produce a percentage of
  functions that were fully selected by GlobalISel

Make this possible by adding llvm::GetStatistics() which returns an
iterator_range that can be used to inspect the statistics that have been
touched during execution. When statistics are disabled (NDEBUG and not
LLVM_ENABLE_STATISTICS) this method will return an empty range.

This patch doesn't address the effect of multiple compilations within the same
process. In such situations, the statistics will be cumulative for all
compilations up to the GetStatistics() call.

Reviewers: qcolombet, rtereshin, aditya_nandakumar, bogner

Reviewed By: rtereshin, bogner

Subscribers: llvm-commits, mgorny

Differential Revision: https://reviews.llvm.org/D43901

llvm-svn: 326723
2018-03-05 17:41:45 +00:00
Rui Ueyama e403c862cc Make llvm::djbHash an inline function.
Differential Revision: https://reviews.llvm.org/D43644

llvm-svn: 326625
2018-03-02 22:00:38 +00:00
Dimitry Andric a73ed459bf Fix llvm-config --system-libs output on FreeBSD and NetBSD
Summary:
For various reasons, CMake's detection mechanism for `backtrace()`
returns an absolute path `/usr/lib/libexecinfo.so` on FreeBSD and
NetBSD.

Since `tools/llvm-config/CMakeLists.txt` only checks if system
libraries start with `-`, this causes `llvm-config --system-libs` to
produce the following incorrect output:

```
-lrt -l/usr/lib/libexecinfo.so -ltinfo -lpthread -lz -lm
```

Fix it by removing the path and the `lib` prefix, to make it look like a
regular short library name, suitable for appending to a `-l` link flag.

This also fixes the `Bindings/Go/go.test` test case, since that always
died with "unable to find library -l/usr/lib/libexecinfo.so".

Reviewers: chandlerc, emaste, joerg, krytarowski

Reviewed By: krytarowski

Subscribers: hans, bdrewery, mgorny, hintonda, llvm-commits

Differential Revision: https://reviews.llvm.org/D42702

llvm-svn: 326358
2018-02-28 20:04:21 +00:00
Jonas Devlieghere 425b248128 [ADT] Recognize ppc as valid architecture in target triple.
Until this patch, only `powerpc` and `ppc32` were recognized as valid
PowerPC 32-bit architectures in a target triple. This was incompatible
with the triple `ppc-apple-darwin` as returned for libObject. I found
out about this when working on a test case using a binary generated on
an old PowerBook G4.

We had the choice of either fix this in the Mach-O object parser or
in the Triple implementation. I chose the latter because it feels like
the most canonical place.

Differential revision: https://reviews.llvm.org/D43760

llvm-svn: 326182
2018-02-27 10:09:58 +00:00
Jonas Devlieghere 560ce2c70f Re-land: "[Support] Replace HashString with djbHash."
This patch removes the HashString function from StringExtraces and
replaces its uses with calls to djbHash from DJB.h.

This change is *almost* NFC. While the algorithm is identical, the
djbHash implementation in StringExtras used 0 as its default seed while
the implementation in DJB uses 5381. The latter has been shown to result
in less collisions and improved avalanching and is used by the DWARF
accelerator tables.

Because some test were implicitly relying on the hash order, I've
reverted to using zero as a seed for the following two files:

  lld/include/lld/Core/SymbolTable.h
  llvm/lib/Support/StringMap.cpp

Differential revision: https://reviews.llvm.org/D43615

llvm-svn: 326091
2018-02-26 15:16:42 +00:00
David Zarzycki f3fa88b288 Test commit
llvm-svn: 326085
2018-02-26 13:05:18 +00:00
Jonas Devlieghere 370bf3ef49 Revert "[Support] Replace HashString with djbHash."
It looks like some of our tests depend on the ordering of hashed values.
I'm reverting my changes while I try to reproduce and fix this locally.

Failing builds:

  lab.llvm.org:8011/builders/lld-x86_64-darwin13/builds/18388
  lab.llvm.org:8011/builders/clang-cmake-x86_64-sde-avx512-linux/builds/6743
  lab.llvm.org:8011/builders/llvm-clang-lld-x86_64-scei-ps4-windows10pro-fast/builds/15607

llvm-svn: 326082
2018-02-26 12:05:18 +00:00
Jonas Devlieghere b9ad175935 [Support] Replace HashString with djbHash.
This removes the HashString function from StringExtraces and replaces
its uses with calls to djbHash from DJB.h

This is *almost* NFC. While the algorithm is identical, the djbHash
implementation in StringExtras used 0 as its seed while the
implementation in DJB uses 5381. The latter has been shown to result in
less collisions and improved avalanching.

https://reviews.llvm.org/D43615
(cherry picked from commit 77f7f965bc9499a9ae768a296ca5a1f7347d1d2c)

llvm-svn: 326081
2018-02-26 11:30:13 +00:00
Hans Wennborg 35d6e944e1 llvm-config: Add advapi32 to --system-libs on Windows (PR36372)
llvm-svn: 325894
2018-02-23 12:20:26 +00:00
Pavel Labath 3b17b84b9c Resubmit r325107 (case folding DJB hash)
The issue was that the has function was generating different results depending
on the signedness of char on the host platform. This commit fixes the issue by
explicitly using an unsigned char type to prevent sign extension and
adds some extra tests.

The original commit message was:

This patch implements a variant of the DJB hash function which folds the
input according to the algorithm in the Dwarf 5 specification (Section
6.1.1.4.5), which in turn references the Unicode Standard (Section 5.18,
"Case Mappings").

To achieve this, I have added a llvm::sys::unicode::foldCharSimple
function, which performs this mapping. The implementation of this
function was generated from the CaseMatching.txt file from the Unicode
spec using a python script (which is also included in this patch). The
script tries to optimize the function by coalescing adjecant mappings
with the same shift and stride (terms I made up). Theoretically, it
could be made a bit smarter and merge adjecant blocks that were
interrupted by only one or two characters with exceptional mapping, but
this would save only a couple of branches, while it would greatly
complicate the implementation, so I deemed it was not worth it.

Since we assume that the vast majority of the input characters will be
US-ASCII, the folding hash function has a fast-path for handling these,
and only whips out the full decode+fold+encode logic if we encounter a
character outside of this range. It might be possible to implement the
folding directly on utf8 sequences, but this would also bring a lot of
complexity for the few cases where we will actually need to process
non-ascii characters.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: mgorny, hintonda, echristo, clayborg, vleschuk, llvm-commits

Differential Revision: https://reviews.llvm.org/D42740

llvm-svn: 325732
2018-02-21 22:36:31 +00:00
Serge Pavlov 76d8ccee2e Report fatal error in the case of out of memory
This is the second part of recommit of r325224. The previous part was
committed in r325426, which deals with C++ memory allocation. Solution
for C memory allocation involved functions `llvm::malloc` and similar.
This was a fragile solution because it caused ambiguity errors in some
cases. In this commit the new functions have names like `llvm::safe_malloc`.

The relevant part of original comment is below, updated for new function
names.

Analysis of fails in the case of out of memory errors can be tricky on
Windows. Such error emerges at the point where memory allocation function
fails, but manifests itself when null pointer is used. These two points
may be distant from each other. Besides, next runs may not exhibit
allocation error.

In some cases memory is allocated by a call to some of C allocation
functions, malloc, calloc and realloc. They are used for interoperability
with C code, when allocated object has variable size and when it is
necessary to avoid call of constructors. In many calls the result is not
checked for null pointer. To simplify checks, new functions are defined
in the namespace 'llvm': `safe_malloc`, `safe_calloc` and `safe_realloc`.
They behave as corresponding standard functions but produce fatal error if
allocation fails. This change replaces the standard functions like 'malloc'
in the cases when the result of the allocation function is not checked
for null pointer.

Finally, there are plain C code, that uses malloc and similar functions. If
the result is not checked, assert statement is added.

Differential Revision: https://reviews.llvm.org/D43010

llvm-svn: 325551
2018-02-20 05:41:26 +00:00
Benjamin Kramer 92387a8744 [Support] Replace hand-written scope_exit with make_scope_exit.
No functionality change intended.

llvm-svn: 325460
2018-02-18 16:05:40 +00:00
Craig Topper 8d02be3bf3 [X86] Add 'sahf' to getHostCPUFeatures so -march=native will pick it up correctly.
Summary: We probably mostly get this right due to family/model/stepping mapping to CPU names. But we should detect it explicitly.

Reviewers: RKSimon, echristo, dim, spatel

Reviewed By: dim

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D43418

llvm-svn: 325439
2018-02-17 16:52:49 +00:00
Serge Pavlov d48042efa8 Report fatal error in the case of out of memory
This is partial recommit of r325224, reverted in 325227. The relevant
part of original comment is below.

Analysis of fails in the case of out of memory errors can be tricky on
Windows. Such error emerges at the point where memory allocation function
fails, but manifests itself when null pointer is used. These two points
may be distant from each other. Besides, next runs may not exhibit
allocation error.

Usual programming practice does not require checking result of 'operator
new' because it throws 'std::bad_alloc' in the case of allocation error.
However, LLVM is usually built with exceptions turned off, so 'new' can
return null pointer. This change installs custom new handler, which causes
fatal error in the case of out of memory. The handler is installed
automatically prior to call to 'main' during construction of a static
object defined in 'lib/Support/ErrorHandling.cpp'. If the application does
not use this file, the handler may be installed manually by a call to
'llvm::install_out_of_memory_new_handler', declared in
'include/llvm/Support/ErrorHandling.h".

Differential Revision: https://reviews.llvm.org/D43010

llvm-svn: 325426
2018-02-17 10:21:33 +00:00
Tim Shen 89337750a0 [APInt] Fix extractBits to correctly handle Result.isSingleWord() case.
Summary: extractBits assumes that `!this->isSingleWord() implies !Result.isSingleWord()`, which may not necessarily be true. Handle both cases.

Reviewers: RKSimon

Subscribers: sanjoy, llvm-commits, hiraditya

Differential Revision: https://reviews.llvm.org/D43363

llvm-svn: 325311
2018-02-16 01:44:36 +00:00
Zachary Turner 2061ad2f83 Silence warning about unused private variable.
llvm-svn: 325275
2018-02-15 18:46:59 +00:00
Zachary Turner acd8791c26 Call FlushFileBuffers on output files.
There is a latent Windows kernel bug, the exact trigger
conditions are not well understood, which can cause a file
to be correctly written, but unable to be correctly read.

The workaround appears to be simply calling FlushFileBuffers.

Differential Revision: https://reviews.llvm.org/D42925

llvm-svn: 325274
2018-02-15 18:36:10 +00:00
Serge Pavlov 4500001905 Revert r325224 "Report fatal error in the case of out of memory"
It caused fails on some buildbots.

llvm-svn: 325227
2018-02-15 09:45:59 +00:00
Serge Pavlov ce719a0def Specify namespace for realloc
llvm-svn: 325226
2018-02-15 09:35:36 +00:00
Serge Pavlov 431502a675 Report fatal error in the case of out of memory
Analysis of fails in the case of out of memory errors can be tricky on
Windows. Such error emerges at the point where memory allocation function
fails, but manifests itself when null pointer is used. These two points
may be distant from each other. Besides, next runs may not exhibit
allocation error.

Usual programming practice does not require checking result of 'operator
new' because it throws 'std::bad_alloc' in the case of allocation error.
However, LLVM is usually built with exceptions turned off, so 'new' can
return null pointer. This change installs custom new handler, which causes
fatal error in the case of out of memory. The handler is installed
automatically prior to call to 'main' during construction of a static
object defined in 'lib/Support/ErrorHandling.cpp'. If the application does
not use this file, the handler may be installed manually by a call to
'llvm::install_out_of_memory_new_handler', declared in
'include/llvm/Support/ErrorHandling.h".

There are calls to C allocation functions, malloc, calloc and realloc.
They are used for interoperability with C code, when allocated object has
variable size and when it is necessary to avoid call of constructors. In
many calls the result is not checked against null pointer. To simplify
checks, new functions are defined in the namespace 'llvm' with the
same names as these C function. These functions produce fatal error if
allocation fails. User should use 'llvm::malloc' instead of 'std::malloc'
in order to use the safe variant. This change replaces 'std::malloc'
in the cases when the result of allocation function is not checked against
null pointer.

Finally, there are plain C code, that uses malloc and similar functions. If
the result is not checked, assert statements are added.

Differential Revision: https://reviews.llvm.org/D43010

llvm-svn: 325224
2018-02-15 09:20:26 +00:00
Pavel Labath 918f60056a Revert r325107 (case folding DJB hash) and subsequent build fix
The "knownValuesUnicode" test in the patch fails on ppc64 and arm64
bots. Reverting while I investigate.

llvm-svn: 325115
2018-02-14 11:06:39 +00:00
Pavel Labath f1440978a1 Implement a case-folding version of DJB hash
Summary:
This patch implements a variant of the DJB hash function which folds the
input according to the algorithm in the Dwarf 5 specification (Section
6.1.1.4.5), which in turn references the Unicode Standard (Section 5.18,
"Case Mappings").

To achieve this, I have added a llvm::sys::unicode::foldCharSimple
function, which performs this mapping. The implementation of this
function was generated from the CaseMatching.txt file from the Unicode
spec using a python script (which is also included in this patch). The
script tries to optimize the function by coalescing adjecant mappings
with the same shift and stride (terms I made up). Theoretically, it
could be made a bit smarter and merge adjecant blocks that were
interrupted by only one or two characters with exceptional mapping, but
this would save only a couple of branches, while it would greatly
complicate the implementation, so I deemed it was not worth it.

Since we assume that the vast majority of the input characters will be
US-ASCII, the folding hash function has a fast-path for handling these,
and only whips out the full decode+fold+encode logic if we encounter a
character outside of this range. It might be possible to implement the
folding directly on utf8 sequences, but this would also bring a lot of
complexity for the few cases where we will actually need to process
non-ascii characters.

Reviewers: JDevlieghere, aprantl, probinson, dblaikie

Subscribers: mgorny, hintonda, echristo, clayborg, vleschuk, llvm-commits

Differential Revision: https://reviews.llvm.org/D42740

llvm-svn: 325107
2018-02-14 10:05:09 +00:00
Sam McCall 6358064d02 Fix off-by-one in set_thread_name which causes truncation to fail on Linux
llvm-svn: 325069
2018-02-13 23:23:59 +00:00