Summary:
Sanitizer blacklist entries currently apply to all sanitizers--there
is no way to specify that an entry should only apply to a specific
sanitizer. This is important for Control Flow Integrity since there are
several different CFI modes that can be enabled at once. For maximum
security, CFI blacklist entries should be scoped to only the specific
CFI mode(s) that entry applies to.
Adding section headers to SpecialCaseLists allows users to specify more
information about list entries, like sanitizer names or other metadata,
like so:
[section1]
fun:*fun1*
[section2|section3]
fun:*fun23*
The section headers are regular expressions. For backwards compatbility,
blacklist entries entered before a section header are put into the '[*]'
section so that blacklists without sections retain the same behavior.
SpecialCaseList has been modified to also accept a section name when
matching against the blacklist. It has also been modified so the
follow-up change to clang can define a derived class that allows
matching sections by SectionMask instead of by string.
Reviewers: pcc, kcc, eugenis, vsk
Reviewed By: eugenis, vsk
Subscribers: vitalybuka, llvm-commits
Differential Revision: https://reviews.llvm.org/D37924
llvm-svn: 314170
Previously the 'Padding' argument was the number of padding
bytes to add. However most callers that use 'Padding' know
how many overall bytes they need to write. With the previous
code this would mean encoding the LEB once to find out how
many bytes it would occupy and then using this to calulate
the 'Padding' value.
See: https://reviews.llvm.org/D36595
Differential Revision: https://reviews.llvm.org/D37494
llvm-svn: 313393
This returns "cortex-a73" for second-generation Kryo; not precisely
correct, but close enough.
Differential Revision: https://reviews.llvm.org/D37724
llvm-svn: 313200
Summary:
Change the type of the Redirects parameter of llvm::sys::ExecuteAndWait,
ExecuteNoWait and other APIs that wrap them from `const StringRef **` to
`ArrayRef<Optional<StringRef>>`, which is safer and simplifies the use of these
APIs (no more local StringRef variables just to get a pointer to).
Corresponding clang changes will be posted as a separate patch.
Reviewers: bkramer
Reviewed By: bkramer
Subscribers: vsk, llvm-commits
Differential Revision: https://reviews.llvm.org/D37563
llvm-svn: 313155
cantFail is the moral equivalent of an assertion that the wrapped call must
return a success value. This patch allows clients to include an associated
error message (the same way they would for an assertion for llvm_unreachable).
If the error message is not specified it will default to: "Failure value
returned from cantFail wrapped call".
llvm-svn: 312066
Add abstract virtual method setDefault() to class Option and implement it in its inheritors in order to be able to set all the options to its default values in user's code without actually knowing all these options. For instance:
for (auto &OM : cl::getRegisteredOptions(*cl::TopLevelSubCommand)) {
cl::Option *O = OM.second;
O->setDefault();
}
Reviewed by: rampitec, Eugene.Zelenko, kasaurov
Differential Revision: http://reviews.llvm.org/D36877
llvm-svn: 311887
handleExpected is similar to handleErrors, but takes an Expected<T> as its first
input value and a fallback functor as its second, followed by an arbitary list
of error handlers (equivalent to the handler list of handleErrors). If the first
input value is a success value then it is returned from handleErrors
unmodified. Otherwise the contained error(s) are passed to handleErrors, along
with the handlers. If handleErrors returns success (indicating that all errors
have been handled) then handleExpected runs the fallback functor and returns its
result. If handleErrors returns a failure value then the failure value is
returned and the fallback functor is never run.
This simplifies the process of re-trying operations that return Expected values.
Without this utility such retry logic is cumbersome as the internal Error must
be explicitly extracted from the Expected value, inspected to see if its
handleable and then consumed:
enum FooStrategy { Aggressive, Conservative };
Expected<Foo> tryFoo(FooStrategy S);
Expected<Foo> Result;
(void)!!Result; // "Check" Result so that it can be safely overwritten.
if (auto ValOrErr = tryFoo(Aggressive))
Result = std::move(ValOrErr);
else {
auto Err = ValOrErr.takeError();
if (Err.isA<HandleableError>()) {
consumeError(std::move(Err));
Result = tryFoo(Conservative);
} else
return std::move(Err);
}
with handleExpected, this can be re-written as:
auto Result =
handleExpected(
tryFoo(Aggressive),
[]() { return tryFoo(Conservative); },
[](HandleableError&) { /* discard to handle */ });
llvm-svn: 311870
Summary: The expected order of pointer-like keys is hash-function-dependent which in turn depends on the platform/environment. Need to come up with a better way to test reverse iteration of containers with pointer-like keys.
Reviewers: dblaikie, mehdi_amini, efriedma, mgrang
Reviewed By: mgrang
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D37128
llvm-svn: 311741
Summary:
If assertions are disabled, but LLVM_ABI_BREAKING_CHANGES is enabled,
this will cause an issue with an unchecked Success. Switching to
consumeError() is the correct way to bypass the check. This patch also
includes disabling 2 tests that can't work without assertions enabled,
since llvm_unreachable() with NDEBUG won't crash.
Reviewers: llvm-commits, lhames
Reviewed By: lhames
Subscribers: lhames, pirama
Differential Revision: https://reviews.llvm.org/D36729
llvm-svn: 311739
This just switches handleAllErrors from using custom assertions that all errors
have been handled to using cantFail. This change involves moving some of the
class and function definitions around though.
llvm-svn: 311631
Summary:
The function widenPath() for Windows also normalizes long path names by
iterating over the path's components and calling append(). The
assumption during the iteration that separators are not returned by the
iterator doesn't hold because the iterators do return a separator when
the path has a drive name. Handle this case by ignoring separators
during iteration.
Reviewers: rnk
Subscribers: danalbert, srhines
Differential Revision: https://reviews.llvm.org/D36752
llvm-svn: 311382
An environment variable can be in one of three states:
1. undefined.
2. defined with a non-empty value.
3. defined but with an empty value.
The windows implementation did not support case 3
(it was not handling errors). The Linux implementation
is already correct.
Differential Revision: https://reviews.llvm.org/D36394
llvm-svn: 311174
formatv_object currently uses the implicitly defined move constructor,
but it is buggy. In typical use-cases, the problem doesn't show-up
because all calls to the move constructor are elided. Thus, the buggy
constructors are never invoked.
The issue especially shows-up when code is compiled using the
-fno-elide-constructors compiler flag. For instance, this is useful when
attempting to collect accurate code coverage statistics.
The exact issue is the following:
The Parameters data member is correctly moved, thus making the
parameters occupy a new memory location in the target
object. Unfortunately, the default copying of the Adapters blindly
copies the vector of pointers, leaving each of these pointers
referencing the parameters in the original object instead of the copied
one. These pointers quickly become dangling when the original object is
deleted. This quickly leads to crashes.
The solution is to update the Adapters pointers when performing a move.
The copy constructor isn't useful for format objects and can thus be
deleted.
This resolves PR33388.
Differential Revision: https://reviews.llvm.org/D34463
llvm-svn: 310475
Summary:
It was added to support clang warnings about includes with case
mismatches, but it ended up not being necessary.
Reviewers: twoh, rafael
Subscribers: hiraditya, llvm-commits
Differential Revision: https://reviews.llvm.org/D36328
llvm-svn: 310078
Found it during work on LLD, it would crash on following
linker script:
SECTIONS { .foo : { *("*®") } }
That happens because ® has int value -82. And chars are used as
array index in code, and are signed by default.
Differential revision: https://reviews.llvm.org/D35891
llvm-svn: 309549
Summary:
Using c++11 enum classes ensures that only valid enum values are used
for ArchKind, ProfileKind, VersionKind and ISAKind. This removes the
need for checks that the provided values map to a proper enum value,
allows us to get rid of AK_LAST and prevents comparing values from
different enums. It also removes a bunch of static_cast
from unsigned to enum values and vice versa, at the cost of introducing
static casts to access AArch64ARCHNames and ARMARCHNames by ArchKind.
FPUKind and ArchExtKind are the only remaining old-style enum in
TargetParser.h. I think it's beneficial to keep ArchExtKind as old-style
enum, but FPUKind can be converted too, but this patch is quite big, so
could do this in a follow-up patch. I could also split this patch up a
bit, if people would prefer that.
Reviewers: rengolin, javed.absar, chandlerc, rovka
Reviewed By: rovka
Subscribers: aemerson, kristof.beyls, llvm-commits
Differential Revision: https://reviews.llvm.org/D35882
llvm-svn: 309287
Summary:
The current yaml::Input constructor takes a StringRef of data as its
first parameter, discarding any filename information that may have been
present when a YAML file was opened. Add an alterate yaml::Input
constructor that takes a MemoryBufferRef, which can have a filename
associated with it. This leads to clearer diagnostic messages.
Sponsored By: DARPA, AFRL
Reviewed By: arphaman
Differential Revision: https://reviews.llvm.org/D35398
Patch by: Jonathan Anderson (trombonehero)
llvm-svn: 308172
Summary: Different JITs and other clients of LLVM may have different needs in how symbol resolution should occur.
Reviewers: v.g.vassilev, lhames, karies
Reviewed By: v.g.vassilev
Subscribers: pcanal, llvm-commits
Differential Revision: https://reviews.llvm.org/D33529
llvm-svn: 307849
the system's version of macOS
sys::getProcessTriple returns LLVM_HOST_TRIPLE, whose system version might not
be the actual version of the system on which the compiler running. This commit
ensures that, for macOS, sys::getProcessTriple returns a triple with the
system's macOS version.
rdar://33177551
Differential Revision: https://reviews.llvm.org/D34446
llvm-svn: 307372
Summary:
This is a follow-up on D34077. Elena observed that the
correctness of the code relies on isPowerOf2(0) returning false.
Adding a test to cover this corner-case.
Reviewers: delena, davide, craig.topper
Reviewed By: davide
Subscribers: llvm-commits
Differential Revision: https://reviews.llvm.org/D34939
llvm-svn: 307046
This is a short-term fix for PR33650 aimed to get the modules build bots green again.
Remove all the places where we use the LLVM_YAML_IS_(FLOW_)?SEQUENCE_VECTOR
macros to try to locally specialize a global template for a global type. That's
not how C++ works.
Instead, we now centrally define how to format vectors of fundamental types and
of string (std::string and StringRef). We use flow formatting for the former
cases, since that's the obvious right thing to do; in the latter case, it's
less clear what the right choice is, but flow formatting is really bad for some
cases (due to very long strings), so we pick block formatting. (Many of the
cases that were using flow formatting for strings are improved by this change.)
Other than the flow -> block formatting change for some vectors of strings,
this should result in no functionality change.
Differential Revision: https://reviews.llvm.org/D34907
Corresponding updates to clang, clang-tools-extra, and lld to follow.
llvm-svn: 306878
The difference from the previous version is the use of decltype, as the
implementation of std::result_of in libc++ did not work correctly for
variadic function like open(2).
Original summary:
This function retries an operation if it was interrupted by a signal
(failed with EINTR). It's inspired by the TEMP_FAILURE_RETRY macro in
glibc, but I've turned that into a template function. I've also added a
fail-value argument, to enable the function to be used with e.g.
fopen(3), which is documented to fail for any reason that open(2) can
fail (which includes EINTR).
The main user of this function will be lldb, but there were also a
couple of uses within llvm that I could simplify using this function.
Reviewers: zturner, silvas, joerg
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33895
llvm-svn: 306671
This is useful when an upper limit on the cache size needs to be
controlled independently of the amount of the amount of free space.
One use case is a machine with a large number of cache directories
(e.g. a buildbot slave hosting a large number of independent build
jobs). By imposing an upper size limit on each cache directory,
users can more easily estimate the server's capacity.
Differential Revision: https://reviews.llvm.org/D34547
llvm-svn: 306126
The fix in r306003 uncovered a pretty fundamental problem that libc++
implementation of std::result_of does not handle the prototype of
open(2) correctly (presumably because it contains ...). This makes the
whole function unusable in its current form, so I am also reverting the
original commit (r305892), which introduced the function, at least until
I figure out a way to solve the libc++ issue.
llvm-svn: 306005
The default value of the ResultT template argument (which was there only
to avoid spelling out the long std::result_of template multiple times)
was being overriden by function call template argument deduction. This
manifested itself as a compiler error when calling the function as
FILE *X = RetryAfterSignal(nullptr, fopen, ...)
because the function would try to assign the result of fopen to
nullptr_t, but a more insidious side effect was that
RetryAfterSignal(-1, read, ...) would return "int" instead of "ssize_t",
losing precision along the way.
I fix this by having the function take the argument in a way that
prevents argument deduction from kicking in and add a test that makes
sure the return type is correct.
llvm-svn: 306003
Summary:
This function retries an operation if it was interrupted by a signal
(failed with EINTR). It's inspired by the TEMP_FAILURE_RETRY macro in
glibc, but I've turned that into a template function. I've also added a
fail-value argument, to enable the function to be used with e.g.
fopen(3), which is documented to fail for any reason that open(2) can
fail (which includes EINTR).
The main user of this function will be lldb, but there were also a
couple of uses within llvm that I could simplify using this function.
Reviewers: zturner, silvas, joerg
Subscribers: mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33895
llvm-svn: 305892
This is a workaround for large file writes. It has been witnessed that
write(2) failing with EINVAL (22) due to a large value (>2G). Thanks to
James Knight for the help with coming up with a sane test case.
llvm-svn: 305846
Previously if you used fmt_align(7, Center) you would get the
output ' 7 '. It may be desirable for the user to specify
the fill character though, for example producing '---7---'. This
patch adds that.
llvm-svn: 305449
Instead use target_link_libraries directly. Thanks to
Juergen Ributzka for the suggestion, which fixes an issue
when llvm is configured with no targets.
llvm-svn: 305421
Many times unit tests for different libraries would like to use
the same helper functions for checking common types of errors.
This patch adds a common library with helpers for testing things
in Support, and introduces helpers in here for integrating the
llvm::Error and llvm::Expected<T> classes with gtest and gmock.
Normally, we would just be able to write:
EXPECT_THAT(someFunction(), succeeded());
but due to some quirks in llvm::Error's move semantics, gmock
doesn't make this easy, so two macros EXPECT_THAT_ERROR() and
EXPECT_THAT_EXPECTED() are introduced to gloss over the difficulties.
Consider this an exception, and possibly only temporary as we
look for ways to improve this.
Differential Revision: https://reviews.llvm.org/D33059
llvm-svn: 305395
Summary: Fixes an issue using RegisterStandardPasses from a statically linked object before PassManagerBuilder::addGlobalExtension is called from a dynamic library.
Reviewers: efriedma, theraven
Reviewed By: efriedma
Subscribers: mehdi_amini, mgorny, llvm-commits
Differential Revision: https://reviews.llvm.org/D33515
llvm-svn: 305303
Running unittests/Support/DynamicLibrary/DynamicLibraryTests fails
when LLVM is configured with -DLLVM_EXPORT_SYMBOLS_FOR_PLUGINS=ON, because
the test's version script only contains symbols extracted from the static libraries,
that the test links with, but not those from the main object/executable itself.
The patch moves the one symbol, needed by the test, to a static library.
Fixes https://bugs.llvm.org/show_bug.cgi?id=32893
Patch by Momchil Velikov.
Differential Revision: https://reviews.llvm.org/D33789
llvm-svn: 305181
Previously extractors tried to be stateless with any additional
context information needed in order to parse items being passed
in via the extraction method. This led to quite cumbersome
implementation challenges and awkwardness of use. This patch
brings back support for stateful extractors, making the
implementation and usage simpler.
llvm-svn: 305093
This creates a new library called BinaryFormat that has all of
the headers from llvm/Support containing structure and layout
definitions for various types of binary formats like dwarf, coff,
elf, etc as well as the code for identifying a file from its
magic.
Differential Revision: https://reviews.llvm.org/D33843
llvm-svn: 304864
clang-format (https://reviews.llvm.org/D33932) to keep primary headers
at the top and handle new utility headers like 'gmock' consistently with
other utility headers.
No other change was made. I did no manual edits, all of this is
clang-format.
This should allow other changes to have more clear and focused diffs,
and is especially motivated by moving some headers into more focused
libraries.
llvm-svn: 304786
This is super awkward, but GCC doesn't let us have template visible when
an argument is an inline function and -fvisibility-inlines-hidden is
used.
llvm-svn: 304175
error C2971: 'llvm::ManagedStatic': template parameter 'Creator': 'CreateDefaultTimerGroup': a variable with non-static storage duration cannot be used as a non-type argument
llvm-svn: 304157
Running unittests/Support/DynamicLibrary/DynamicLibraryTests fails when LLVM is
configured with LLVM_EXPORT_SYMBOLS_FOR_PLUGINS=ON, because the test's version
script only contains symbols extracted from the static libraries, that the test
links with, but not those from the main object/executable itself. The patch
explicitly exports the one symbol needed by the test.
This change fixes https://bugs.llvm.org/show_bug.cgi?id=32893
Patch authored by Momchil Velikov.
Differential Revision: https://reviews.llvm.org/D33490
llvm-svn: 303979
driver-mode recognition in clang (this is because the sysctl method
always returns one and only one executable path, even for an executable
with multiple links):
Fix DynamicLibraryTest.cpp on FreeBSD and NetBSD
Summary:
After rL301562, on FreeBSD the DynamicLibrary unittests fail, because
the test uses getMainExecutable("DynamicLibraryTests", Ptr), and since
the path does not contain any slashes, retrieving the main executable
will not work.
Reimplement getMainExecutable() for FreeBSD and NetBSD using sysctl(3),
which is more reliable than fiddling with relative or absolute paths.
Also add retrieval of the original argv[] from the GoogleTest framework,
to use as a fallback for other OSes.
Reviewers: emaste, marsupial, hans, krytarowski
Reviewed By: krytarowski
Subscribers: krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D33171
llvm-svn: 303285
We have to check gCrashRecoveryEnabled before using __try.
In other words, SEH works too well and we ended up recovering from
crashes in implicit module builds that we weren't supposed to. Only
libclang is supposed to enable CrashRecoveryContext to allow implicit
module builds to crash.
llvm-svn: 303279
Summary:
It avoids problems when other libraries raise exceptions. In particular,
OutputDebugString raises an exception that the debugger is supposed to
catch and suppress. VEH kicks in first right now, and that is entirely
incorrect.
Unfortunately, GCC does not support SEH, so I've kept the old buggy VEH
codepath around. We could fix it with SetUnhandledExceptionFilter, but
that is not per-thread, so a well-behaved library shouldn't set it.
Reviewers: zturner
Subscribers: llvm-commits, mgorny
Differential Revision: https://reviews.llvm.org/D33261
llvm-svn: 303274
The operator-> implementation comes from iterator_facade_base, so it should
just work given that the iterator has a tested operator*. But r302257 showed
that required careful handling of for the const qualifier. This patch ensures
the fix in r302257 doesn't regress.
Differential Revision: https://reviews.llvm.org/D33249
llvm-svn: 303215
Summary:
After rL301562, on FreeBSD the DynamicLibrary unittests fail, because
the test uses getMainExecutable("DynamicLibraryTests", Ptr), and since
the path does not contain any slashes, retrieving the main executable
will not work.
Reimplement getMainExecutable() for FreeBSD and NetBSD using sysctl(3),
which is more reliable than fiddling with relative or absolute paths.
Also add retrieval of the original argv[] from the GoogleTest framework,
to use as a fallback for other OSes.
Reviewers: emaste, marsupial, hans, krytarowski
Reviewed By: krytarowski
Subscribers: krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D33171
llvm-svn: 303015
Otherwise, each CPU has to manually specify the extensions it supports,
even though they have to be a superset of the base arch extensions.
And when there's redundant data there's stale data, so most of the CPUs
lie about the features they support (almost none lists AEK_FP).
Instead, do the saner thing: add the optional extensions on top of the
base extensions provided by the architecture.
The ARM TargetParser has the same behavior.
Differential Revision: https://reviews.llvm.org/D32780
llvm-svn: 302078
This was reported by the ASAN bot, and it turned out to be
a fairly fundamental problem with the design of VarStreamArray
and the way it passes context information to the extractor.
The fix was cumbersome, and I'm not entirely pleased with it,
so I plan to revisit this design in the future when I'm not
pressed to get the bots green again. For now, this fixes
the issue by storing the context information by value instead
of by reference, and introduces some impossibly-confusing
template magic to make things "work".
llvm-svn: 301999
Reviewers: zturner, hansw, hans
Reviewed By: hans
Subscribers: hans, llvm-commits
Differential Revision: https://reviews.llvm.org/D32611
llvm-svn: 301595
libraries are properly unloaded when llvm_shutdown is called.
Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:
JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv
Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.
Reviewers: chapuni, v.g.vassilev, lhames
Reviewed By: lhames
Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits
Differential Revision: https://reviews.llvm.org/D30107
llvm-svn: 301562
libraries are properly unloaded when llvm_shutdown is called.
Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:
JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv
Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.
Reviewers: chapuni, v.g.vassilev, lhames
Reviewed By: lhames
Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits
Differential Revision: https://reviews.llvm.org/D30107
llvm-svn: 301236
Summary: In rL297945, jhenderson added methods for setting permissions
to sys::fs, but some of the unittests that attempt to set sticky bits
(01000) on files fail on modern BSDs, such as FreeBSD, NetBSD and
OpenBSD. This is because those systems do not allow regular users to
set sticky bits on files, only on directories. Fix it by disabling
these particular tests on modern BSDs.
Reviewers: emaste, brad, jhenderson
Reviewed By: jhenderson
Subscribers: joerg, krytarowski, llvm-commits
Differential Revision: https://reviews.llvm.org/D32120
llvm-svn: 301220
The changes are causing the i686-mingw32 build to fail.
This reverts commit r301153, and the changes for a separate warning on i686-mingw32 in r301155 and r301156.
llvm-svn: 301157
libraries are properly unloaded when llvm_shutdown is called.
Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:
JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv
Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.
Reviewers: chapuni, v.g.vassilev, lhames
Reviewed By: lhames
Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits
Differential Revision: https://reviews.llvm.org/D30107
llvm-svn: 301153
The hardware div feature refers only to Thumb, but because of its name
it is tempting to use it to check for hardware division in general,
which may cause problems in ARM mode. See https://reviews.llvm.org/D32005.
This patch adds "Thumb" to its name, to make its scope clear. One
notable place where I haven't made the change is in the feature flag
(used with -mattr), which is still hwdiv. Changing it would also require
changes in a lot of tests, including clang tests, and it doesn't seem
like it's worth the effort.
Differential Revision: https://reviews.llvm.org/D32160
llvm-svn: 300827
Frequently you you want a bitmask consisting of a specified
number of 1s, either at the beginning or end of a word.
The naive way to do this is to write
template<typename T>
T leadingBitMask(unsigned N) {
return (T(1) << N) - 1;
}
but using this function you cannot produce a word with every
bit set to 1 (i.e. leadingBitMask<uint8_t>(8)) because left
shift is undefined when N is greater than or equal to the
number of bits in the word.
This patch provides an efficient, branch-free implementation
that works for all values of N in [0, CHAR_BIT*sizeof(T)]
Differential Revision: https://reviews.llvm.org/D32212
llvm-svn: 300710
Often you have a unique_ptr<T> where T supports LLVM's
casting methods, and you wish to cast it to a unique_ptr<U>.
Prior to this patch, this requires doing hacky things like:
unique_ptr<U> Casted;
if (isa<U>(Orig.get()))
Casted.reset(cast<U>(Orig.release()));
This is overly verbose, and it would be nice to just be able
to use unique_ptr directly with cast and dyn_cast. To this end,
this patch updates cast<> to work directly with unique_ptr<T>,
so you can now write:
auto Casted = cast<U>(std::move(Orig));
Since it's possible for dyn_cast<> to fail, however, we choose
to use a slightly different API here, because it's awkward to
write
if (auto Casted = dyn_cast<U>(std::move(Orig))) {}
when Orig may end up not having been moved at all. So the
interface for dyn_cast is
if (auto Casted = unique_dyn_cast<U>(Orig)) {}
Where the inclusion of `unique` in the name of the cast operator
re-affirms that regardless of success of or fail of the casting,
exactly one of the input value and the return value will contain
a non-null result.
Differential Revision: https://reviews.llvm.org/D31890
llvm-svn: 300098
This shares detection logic with ARM(32), since AArch64 capable CPUs may
also run in 32-bit system mode.
We observe weird /proc/cpuinfo output for MSM8992 and MSM8994, where
they report all CPU cores as one single model, depending on which CPU
core the kernel is running on. As a workaround, we hardcode the known
CPU part name for these SoCs.
For big.LITTLE systems, this patch would only return the part name of
the first core (usually the little core). Proper support will be added
in a follow-up change.
Differential Revision: D31675
llvm-svn: 299458
Vlad Tsyrklevich