Commit Graph

1059 Commits

Author SHA1 Message Date
Aaron Ballman ea9c3f25a7 Silence an MSVC C4189 warning about a local variable being initialized but not used; NFC.
llvm-svn: 336298
2018-07-04 21:22:28 +00:00
Andrew Ng 089303d8ff [ThinLTO] Update ThinLTO cache file atimes when on Windows
ThinLTO cache file access times are used for expiration based pruning
and since Vista, file access times are not updated by Windows by
default:

https://blogs.technet.microsoft.com/filecab/2006/11/07/disabling-last-access-time-in-windows-vista-to-improve-ntfs-performance

This means on Windows, cache files are currently being pruned from
creation time. This change manually updates cache files that are
accessed by ThinLTO, when on Windows.

Patch by Owen Reynolds.

Differential Revision: https://reviews.llvm.org/D47266

llvm-svn: 336276
2018-07-04 14:17:10 +00:00
Chandler Carruth 9e0108d90c [Support] This sanity check in the test only works with certain versions
of libstdc++, not just certain versions of GCC. The original macros
broke when using Clang + libstdc++4.9 sadly.

Sadly, testing for versions of libstdc++ has been extremely problematic
in the past, so I'm just narrowing this down to Windows and when using
libc++ as that seems at least very unlikely to keep build bots broken.

llvm-svn: 336174
2018-07-03 07:51:01 +00:00
Chandler Carruth f814ad8932 [Support] Fix llvm::unique_function when building with GCC 4.9 by
introducing llvm::trivially_{copy,move}_constructible type traits.

This uses a completely portable implementation of these traits provided
by Richard Smith. You can see it on compiler explorer in all its glory:

  https://godbolt.org/g/QEDZjW

I have transcribed it, clang-formatted it, added some comments, and made
the tests fit into a unittest file.

I have also switched llvm::unique_function over to use these new, much
more portable traits. =D

Hopefully this will fix the build bot breakage from my prior commit.

llvm-svn: 336161
2018-07-03 01:18:21 +00:00
Benjamin Kramer a1f629c4cf [SupportTests] Silence -Wsign-compare warnings
llvm-svn: 335921
2018-06-28 21:03:24 +00:00
Zachary Turner 402ab4964e Fix padding with custom character in formatv.
The format string for formatv allows to specify a custom padding
character instead of the default space.  This custom character was
parsed correctly, but not passed on to the formatter.

Patch by Marcel Köppe
Differential Revision: https://reviews.llvm.org/D48140

llvm-svn: 335915
2018-06-28 20:09:37 +00:00
Zachary Turner 1adca7c4a5 Add a flag to FileOutputBuffer that allows modification.
FileOutputBuffer creates a temp file and on commit atomically
renames the temp file to the destination file.  Sometimes we
want to modify an existing file in place, but still have the
atomicity guarantee.  To do this we can initialize the contents
of the temp file from the destination file (if it exists), that
way the resulting FileOutputBuffer can have only selective
bytes modified.  Committing will then atomically replace the
destination file as desired.

llvm-svn: 335902
2018-06-28 18:49:09 +00:00
Nico Weber 0d63dbbc32 Build TaskQueueTest in threads=on builds, fixes regression from r335608.
llvm-svn: 335724
2018-06-27 11:52:30 +00:00
Nico Weber a7f9e66cfd Fix LLVM_ENABLE_THREADS=0 builds after r335440.
llvm-svn: 335608
2018-06-26 14:42:48 +00:00
Zachary Turner eee66518af One more build fix for non MSVC compilers.
llvm-svn: 335443
2018-06-25 04:38:03 +00:00
Zachary Turner 35169f6698 Add a TaskQueue that can serialize work on a ThreadPool.
We have ThreadPool, which can execute work asynchronously on N
background threads, but sometimes you need to make sure the work
is executed asynchronously but also serially.  That is, if task
B is enqueued after task A, then task B should not begin until
task A has completed.  This patch adds such a class.

Differential Revision: https://reviews.llvm.org/D48240

llvm-svn: 335440
2018-06-25 03:13:09 +00:00
Zachary Turner 9b8b0794b8 Revert "Enable ThreadPool to queue tasks that return values."
This is failing to compile when LLVM_ENABLE_THREADS is false,
and the fix is not immediately obvious, so reverting while I look
into it.

llvm-svn: 334658
2018-06-13 21:24:19 +00:00
Zachary Turner 1b76a128a8 Enable ThreadPool to support tasks that return values.
Previously ThreadPool could only queue async "jobs", i.e. work
that was done for its side effects and not for its result.  It's
useful occasionally to queue async work that returns a value.
From an API perspective, this is very intuitive.  The previous
API just returned a shared_future<void>, so all we need to do is
make it return a shared_future<T>, where T is the type of value
that the operation returns.

Making this work required a little magic, but ultimately it's not
too bad.  Instead of keeping a shared queue<packaged_task<void()>>
we just keep a shared queue<unique_ptr<TaskBase>>, where TaskBase
is a class with a pure virtual execute() method, then have a
templated derived class that stores a packaged_task<T()>.  Everything
else works out pretty cleanly.

Differential Revision: https://reviews.llvm.org/D48115

llvm-svn: 334643
2018-06-13 19:29:16 +00:00
George Karpenkov 788087f5f8 Add checkMulAdd helper function to CheckedArithmetic
Multiplication followed by addition
(https://en.wikipedia.org/wiki/Multiply–accumulate_operation) is a
sufficiently common use-case to warrant a separate helper.

Differential Revision: https://reviews.llvm.org/D48138

llvm-svn: 334635
2018-06-13 18:32:02 +00:00
George Karpenkov 3bbaeaf673 Change checked arithmetic functions API to return Optional
Returning optional is much safer.
The previous API had potential to cause use of undefined variables, if
the value passed by pointer was accidentally read afterwards.

Differential Revision: https://reviews.llvm.org/D48137

llvm-svn: 334634
2018-06-13 18:31:43 +00:00
Hans Wennborg 12ba9ec929 Do not enforce absolute path argv0 in windows
Even if we support no-canonical-prefix on
clang-cl(https://reviews.llvm.org/D47480), argv0 becomes absolute path
in clang-cl and that embeds absolute path in /showIncludes.

This patch removes such full path normalization from InitLLVM on
windows, and that removes absolute path from clang-cl output
(obj/stdout/stderr) when debug flag is disabled.

Patch by Takuto Ikuta!

Differential Revision https://reviews.llvm.org/D47578

llvm-svn: 334602
2018-06-13 14:29:26 +00:00
Zachary Turner 08426e1f9f Refactor ExecuteAndWait to take StringRefs.
This simplifies some code which had StringRefs to begin with, and
makes other code more complicated which had const char* to begin
with.

In the end, I think this makes for a more idiomatic and platform
agnostic API.  Not all platforms launch process with null terminated
c-string arrays for the environment pointer and argv, but the api
was designed that way because it allowed easy pass-through for
posix-based platforms.  There's a little additional overhead now
since on posix based platforms we'll be takign StringRefs which
were constructed from null terminated strings and then copying
them to null terminate them again, but from a readability and
usability standpoint of the API user, I think this API signature
is strictly better.

llvm-svn: 334518
2018-06-12 17:43:52 +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
Mikhail Maltsev fa5a728657 [Unittests] Change linker flags of dynamic library tests
A recent change https://reviews.llvm.org/D46898 which had no intended
behavior change, actually modified the linker flags used when linking
the dynamic libraries used by the DynamicLibraryTests unit test. This
made the test fail in our testing environment which runs the tests
from an NFS share. Prior to D46898 the two libraries used by the test
were different (because the library name used to be embedded into the
binary), and after the change they became bit-to-bit identical. This
causes dlopen to return the same handle when these two libraries are
loaded from an NFS share, and the test expects two different handles.

This patch reverts the part of D46898 that is responsible for
changing the linker flags.

Differential Revision: https://reviews.llvm.org/D47469

llvm-svn: 334394
2018-06-11 09:15:37 +00:00
Zachary Turner 1f67a3cba9 [FileSystem] Split up the OpenFlags enumeration.
This breaks the OpenFlags enumeration into two separate
enumerations: OpenFlags and CreationDisposition.  The first
controls the behavior of the API depending on whether or not
the target file already exists, and is not a flags-based
enum.  The second controls more flags-like values.

This yields a more easy to understand API, while also allowing
flags to be passed to the openForRead api, where most of the
values didn't make sense before.  This also makes the apis more
testable as it becomes easy to enumerate all the configurations
which make sense, so I've added many new tests to exercise all
the different values.

llvm-svn: 334221
2018-06-07 19:58:58 +00:00
Evandro Menezes b2c8244715 [AArch64, ARM] Add support for Samsung Exynos M4
Create a separate feature set for Exynos M4 and add test cases.

llvm-svn: 334115
2018-06-06 18:56:00 +00:00
Ilya Biryukov 5413510e32 [YAML] Quote multiline string scalars
Summary:
Otherwise, the YAML parser breaks when trying to read them back in
'key: multiline_string_value' cases.

This patch fixes a problem when serializing structs which contain multi-line strings.
E.g., if we try to serialize  the following struct
```
{ "key1": "first line\nsecond line",
  "key2": "another string" }`
```

Before this patch, we got the YAML output that failed to parse:
```
key1: first line
second line
key2: another string
```

After the patch, we get:
```
key1: 'first line
second line'
key2: another string
```

Reviewers: sammccall

Reviewed By: sammccall

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D47468

llvm-svn: 333527
2018-05-30 10:40:11 +00:00
Peter Collingbourne e3f652973e Support: Simplify endian stream interface. NFCI.
Provide some free functions to reduce verbosity of endian-writing
a single value, and replace the endianness template parameter with
a field.

Part of PR37466.

Differential Revision: https://reviews.llvm.org/D47032

llvm-svn: 332757
2018-05-18 19:46:24 +00:00
Nico Weber 718a42cfce use standard llvm cmake formatting for targets defined in plugin tests
llvm-svn: 332709
2018-05-18 12:42:30 +00:00
Greg Clayton f81f3a838a Revert 332508 as it caused problems in the clang test suite.
llvm-svn: 332555
2018-05-16 23:29:36 +00:00
Greg Clayton b24957e22a Fix llvm::sys::path::remove_dots() to return "." instead of an empty path.
Differential Revision: https://reviews.llvm.org/D46887

llvm-svn: 332508
2018-05-16 18:25:51 +00:00
Nico Weber 1238981938 Give shared modules in unittests the platform-native extension, make PipSqueak a MODULE
As far as I can tell from revision history, there's no good reason to call
these files .so instead of .dll in Windows, so use the normal extension.

Also change PipSquak from SHARED to MODULE -- it's never passed to
target_link_libraries() and only loaded via dlopen(), so MODULE is more
appropriate. This makes it possible to delete a workaround for SHARED ldflags
being not quite right as well.

No intended behavior change.
https://reviews.llvm.org/D46898

llvm-svn: 332487
2018-05-16 16:29:05 +00:00
Benjamin Kramer ec8598efb1 Use perfect forwarding to deduplicate code in unit test. NFC.
llvm-svn: 332388
2018-05-15 20:08:15 +00:00
Nico Weber 8a95329923 Rename three cxx files in unittests to cpp.
LLVM uses cpp as its C++ file extension, these are the only three cxx file in
the monorepo. These files apparently were called to escape a CMake check -- use
the LLVM_OPTIONAL_SOURCES mechanism that's meant as an escape for this case
instead.

No intended behavior change.
https://reviews.llvm.org/D46843

llvm-svn: 332368
2018-05-15 16:30:30 +00:00
Eric Liu 5390e36953 Fix broken asan Support tests
The asan failures were caught in google internal asan tests after r332311
o Make StackOption support cl::list
o Rememeber to removeArguments for cl::alias in tests.

llvm-svn: 332354
2018-05-15 13:43:20 +00:00
Keno Fischer 8248d7c661 [CommandLine] Error message for incorrect PositionalEatArgs usage
Summary:
bugpoint has several options specified as `PositionalEatArgs` to pass
options through to the underlying tool, e.g. `-tool-args`. The `-help`
message suggests the usage is: `-tool-args=<string>`. However, this is
misleading, because that's not how these arguments work. Rather than taking
a value, the option consumes all positional arguments until the next
recognized option (or all arguments if `--` is specified at some point).
To make this slightly clearer, instead print the help as:
```
  -tool-args <string>...                            - <tool arguments>...
```
Additionally, add an error if the user attempts to use a `PositionalEatArgs`
argument with a value, instead of silently ignoring it. Example:
```
./bin/bugpoint -tool-args=-mpcu=skylake-avx512
bugpoint: for the -tool-args option: This argument does not take a value.
    Instead, it consumes any positional arguments until the next recognized option.
```

Reviewed By: aprantl
Differential Revision: https://reviews.llvm.org/D46787

llvm-svn: 332311
2018-05-14 23:26:06 +00:00
Pavel Labath d20289b31a [Support/Path] Make handling of paths like "///" consistent
Summary:
Various path functions were not treating paths consisting of slashes
alone consistently. For example, the iterator-based accessors decomposed the
path "///" into two elements: "/" and ".". This is not too bad, but it
is different from the behavior specified by posix:
```
A pathname that contains ***at least one non-slash character*** and that
ends with one or more trailing slashes shall be resolved as if a single
dot character ( '.' ) were appended to the pathname.
```
More importantly, this was different from how we treated the same path
in the filename+parent_path functions, which decomposed this path into
"." and "". This was completely wrong as it lost the information that
this was an absolute path which referred to the root directory.

This patch fixes this behavior by making sure all functions treat paths
consisting of (back)slashes alone the same way as "/". I.e., the
iterator-based functions will just report one component ("/"), and the
filename+parent_path will decompose them into "/" and "".

A slightly controversial topic here may be the treatment of "//". Posix
says that paths beginning with "//" may have special meaning and indeed
we have code which parses paths like "//net/foo/bar" specially. However,
as we were already not being consistent in parsing the "//" string
alone, and any special parsing for it would complicate the code further,
I chose to treat it the same way as longer sequences of slashes (which
are guaranteed to be the same as "/").

Another slight change of behavior is in the parsing of paths like
"//net//". Previously the last component of this path was ".". However,
as in our parsing the "//net" part in this path was the same as the
"drive" part in "c:\" and the next slash was the "root directory", it
made sense to treat "//net//" the same way as "//net/" (i.e., not to add
the extra "." component at the end).

Reviewers: zturner, rnk, dblaikie, Bigcheese

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45942

llvm-svn: 331876
2018-05-09 13:21:16 +00:00
Adrian Prantl 5f8f34e459 Remove \brief commands from doxygen comments.
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

Differential Revision: https://reviews.llvm.org/D46290

llvm-svn: 331272
2018-05-01 15:54:18 +00:00
Nico Weber 432a38838d IWYU for llvm-config.h in llvm, additions.
See r331124 for how I made a list of files missing the include.
I then ran this Python script:

    for f in open('filelist.txt'):
        f = f.strip()
        fl = open(f).readlines()

        found = False
        for i in xrange(len(fl)):
            p = '#include "llvm/'
            if not fl[i].startswith(p):
                continue
            if fl[i][len(p):] > 'Config':
                fl.insert(i, '#include "llvm/Config/llvm-config.h"\n')
                found = True
                break
        if not found:
            print 'not found', f
        else:
            open(f, 'w').write(''.join(fl))

and then looked through everything with `svn diff | diffstat -l | xargs -n 1000 gvim -p`
and tried to fix include ordering and whatnot.

No intended behavior change.

llvm-svn: 331184
2018-04-30 14:59:11 +00:00
Nico Weber 712e8d29c4 s/LLVM_ON_WIN32/_WIN32/, llvm
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.

This moves over all uses of the macro, but doesn't remove the definition
of it in (llvm-)config.h yet.

llvm-svn: 331127
2018-04-29 00:45:03 +00:00
Pavel Labath 60b7132a7c [Support/Path] Add more tests and improve failure messages of existing ones
Summary:
I am preparing a patch to the path function. While working on it, I
noticed that some of the areas are lacking test coverage (e.g. filename
and parent_path functions), so I add more tests to guard against
regressions there.

I have also found the failure messages hard to understand, so I rewrote
some existing test to give more actionable messages when they fail:
- for tests which run over multiple inputs, I use SCOPED_TRACE, to show
  which of the inputs caused the actual failure.
- for comparisons of vectors, I use gmock's container matchers, which
  will print out the full container contents (and the elements that
  differ) when they fail to match.

Reviewers: zturner, espindola

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D45941

llvm-svn: 330691
2018-04-24 08:29:20 +00:00
Pavel Labath 397e150ddc [Testing/Support] Make Failed() matcher work with abstract error types
Failed<ErrorInfoBase>() did not compile, because it was attempting to
create a copy of the Error object when passing it to the nested matcher,
which was not possible because ErrorInfoBase is abstract.

This commit fixes the problem by making sure we pass the ErrorInfo
object by reference, which also improves the handling of non-abstract
objects, as we avoid potentially slicing an object during the copy.

llvm-svn: 329703
2018-04-10 14:11:53 +00:00
Vitaly Buka a8b32dec67 Fix stack-use-after-scope in test previously hidden by -fmerge-all-constants
llvm-svn: 329489
2018-04-07 09:46:00 +00:00
Mandeep Singh Grang 13e70cb181 [unittests] Change std::sort to llvm::sort in response to r327219
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.

llvm-svn: 329475
2018-04-07 01:29:45 +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
Max Moroz 650fd6c31c [llvm-cov] Prevent llvm-cov from hanging when a symblink doesn't exist.
Summary:
Previous code hangs indefinitely when trying to iterate through a
symbol link file that points to an non-exist directory. This change
fixes the bug to make the addCollectedPath function exit ealier and
print out correct warning messages.

Patch by Yuke Liao (@liaoyuke).

Reviewers: Dor1s, vsk

Reviewed By: vsk

Subscribers: bruno, mgrang, llvm-commits

Differential Revision: https://reviews.llvm.org/D44960

llvm-svn: 329338
2018-04-05 19:43:24 +00:00
Pavel Labath 510725c2d6 [Testing/Support]: Better matching of Error failure states
Summary:
The existing Failed() matcher only allowed asserting that the operation
failed, but it was not possible to verify any details of the returned
error.

This patch adds two new matchers, which make this possible:
- Failed<InfoT>() verifies that the operation failed with a single error
  of a given type.
- Failed<InfoT>(M) additionally check that the contained error info
  object is matched by the nested matcher M.

To make these work, I've changed the implementation of the ErrorHolder
class. Now, instead of just storing the string representation of the
Error, it fetches the ErrorInfo objects and stores then as a list of
shared pointers. This way, ErrorHolder remains copyable, while still
retaining the full information contained in the Error object.

In case the Error object contains two or more errors, the new matchers
will fail to match, instead of trying to match all (or any) of the
individual ErrorInfo objects. This seemed to be the most sensible
behavior for when one wants to match exact error details, but I could be
convinced otherwise...

Reviewers: zturner, lhames

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D44925

llvm-svn: 329288
2018-04-05 14:32:10 +00:00
Graydon Hoare b62f86a6b7 [YAML] Remove unit test of multibyte non-printable escaping that uses C++11 escapes
llvm-svn: 328665
2018-03-27 20:46:26 +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
Benjamin Kramer 38a77ae91f [Support] Pacify -Wsign-compare in unit test.
llvm-svn: 327070
2018-03-08 21:54:30 +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
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
George Karpenkov 3f547fe857 Utility functions for checked arithmetic
Provide checkedAdd and checkedMul functions, providing checked
arithmetic on signed integers.

Differential Revision: https://reviews.llvm.org/D43704

llvm-svn: 326516
2018-03-02 00:30:43 +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