The idea is that, other parts of the libc which require thread/lock
support will be able to use this platform independent setup.
With this change, only the linux implementation of a mutex type has been
moved to the new library. Because of this, there is some duplication
between the new library and src/threads/linux. A follow up change will
move all of src/threads/linux to the new library. The duplication should
be eliminated with that move.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D120795
With modern architectures having a thread pointer and language supporting
thread locals, there is no reason to use a function intermediary to access
the thread local errno value.
The entrypoint corresponding to errno has been replaced with an object
library as there is no formal entrypoint for errno anymore.
Reviewed By: jeffbailey, michaelrj
Differential Revision: https://reviews.llvm.org/D120920
The upstream project ships CMake rules for building vanilla gtest/gmock which conflict with the names chosen by LLVM. Since LLVM's build rules here are quite specific to LLVM, prefixing them to avoid collision is the right thing (i.e. there does not appear to be a path to letting someone *replace* LLVM's googletest with one they bring, so co-existence should be the goal).
This allows LLVM to be included with testing enabled within projects that themselves have a dependency on an official gtest release.
Reviewed By: mehdi_amini
Differential Revision: https://reviews.llvm.org/D120789
New methods to the Atomic class have been added as required. Futex
related types have been consolidated at a common place.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D120705
Add LLVM_LIBC_CLANG_TIDY option and allow LLVM_LIBC_ENABLE_LINTING without full build.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119180
Only the methods currently required by the libc have been added.
Most of the existing uses of atomic operations have been switched over
to this new class. A future change will clean up the rest of uses.
This change now allows building mutex and condition variable code with a
C++ compiler which does not have stdatomic.h, for example g++.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D120642
__builtin_clz requires just a single instruction on x86 and arm, so this is a performance improvement.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D120579
The benchmark framework synthesizes fake "aggregate" Samples representing mean, median and cv.
We're only interested in "iteration" samples.
Differential Revision: https://reviews.llvm.org/D120062
Often atexit is implemented using __cxa_atexit. I have not implemented __cxa_atexit here because it potentially requires more discussion. It is unique for llvm-libc (I think) that it is an exported symbol that wouldn’t be defined in any spec file because it doesn’t have a header. Implementing it will be trivial given what is here already, but I figured it would be more contentious so it can be implemented later.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D119512
Algorithm for hypotf: compute (a*a + b*b) in double precision, then use Dekker's algorithm to find the rounding error, and then correcting it after taking its square-root.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D118157
The prior page was the proposal doc, this one is now
more about what the project intends to do, written in the
present tense.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119379
This implements a basic arm64 loader for Linux, and all the currently
enabled linker tests pass. TLS is not implemented, and functions
using it will have undefined behaviour. Notably, the TLS test is
currently disabled on x86_64.
Much of the structure is copied from x86_64 to allow for a refactoring
of the start code between architectures.
Tested:
ninja libc_loader_tests on aarch64-linux.
Co-authored-by: Raman Tenneti <rtenneti@google.com>
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119641
Previously, building LLVM-libc with GWP ASAN was conditioned on the flag
COMPILER_RT_BUILD_GWP_ASAN, which caused issues do to the default value
of the flag being set in the compiler-rt cmake, which is seperate. Now
GWP ASAN is included based on if it exists as a target, which is more
consistent.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119789
Simplify the logic when the exponent difference is at least MantissaLength + 2, while still maintaining correct rounding for all rounding modes.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119843
Add support for getenv as defined by the Open Group's "System Interface &
Header" in https://pubs.opengroup.org/onlinepubs/7908799/xsh/getenv.html
getenv requires a standard way of accessing the environment,
so a pointer to the environment is added to the startup in crt1.
Consquently, this function is not usable on top of other libcs.
Added starts_with method to StringView. getenv function uses it.
Co-authored-by: Jeff Bailey <jeffbailey@google.com>
Reviewed By: sivachandra, rtenneti
Differential Revision: https://reviews.llvm.org/D119403
Previously, allocator functions were only available if they were included
from scudo or by using the system libc headers (i.e. by turning off the
full build). This patch changes the logic to include the prototypes for
the allocator functitons in all cases, which allows the linker to link
in the system's allocator.
Reviewed By: sivachandra, abrachet
Differential Revision: https://reviews.llvm.org/D119587
the vector class, due to being dynamically resized, needs malloc. This
fixes the build so that it only includes it when malloc should be
available.
Differential Revision: https://reviews.llvm.org/D119464
Add a basic implementation of the vector class for use internally to
LLVM-libc.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D118954
GCC complains about undefined reference in LibcTest.cpp and indeed the wrong version of the template has been explicitly instanciated.
This is necessary to get llvm-libc compile with GCC.
Mentionning D119002 here for navigability.
Differential Revision: https://reviews.llvm.org/D119242
Although type punning is defined for union in C, it is UB in C++.
This patch introduces a bit_cast function to convert between types in a safe way.
This is necessary to get llvm-libc compile with GCC.
This patch is extracted from D119002.
Differential Revision: https://reviews.llvm.org/D119145
These were all the non OS agnostic implementations I could find in general directories.
Currently none of these functions are actually enabled, but for when they do it makes sense that they be in linux/ specific directories.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D119164
This implementation relies on storing data in registers for sizes up to 128B.
Then depending on whether `dst` is less (resp. greater) than `src` we move data forward (resp. backward) by chunks of 32B.
We first make sure one of the pointers is aligned to increase performance on large move sizes.
Differential Revision: https://reviews.llvm.org/D114637
llvm-libc exhibits a C interface but its source is C++.
This patch explicitly disables the use of exceptions and RTTI when compiling the entrypoints.
Differential Revision: https://reviews.llvm.org/D118889
CMAKE_CXX_STANDARD 14 is set in the llvm-project/llvm folder overriding all COMPILE_OPTIONS -std=c++17. We need to override the CXX_STANDARD property of the target in order to set the correct C++ standard flags.
Reviewed By: gchatelet
Differential Revision: https://reviews.llvm.org/D118871
The LLVM Libc project is no longer just a proposal and should have
a webpage tracking the status of the project. This changes
puts the pieces into the right place so that the webpage can be
created.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117436
They are implemented as simple syscall wrappers. The file creation
macros have been put in a header file as a temporary solution until we
have a cleaner approach to listing platform relevant macros.
Reviewed By: abrachet
Differential Revision: https://reviews.llvm.org/D118396
Guard sqrt_80_bit_long_double.h header to not be included with aarch64.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D118389
The type names in the spec are just sugar used by the header generator to
generate the function prototype. Giving the VarArgType a name of "..."
allows the header generator to treat and generate the "type name" for var
arg parameters similar to how it does for any other type.
Refactor sqrt implementations:
- Move architecture specific instructions from `src/math/<arch>` to `src/__support/FPUtil/<arch>` folder.
- Move generic implementation of `sqrt` to `src/__support/FPUtil/generic` folder and add it as a header library.
- Use `src/__support/FPUtil/sqrt.h` for architecture/generic selections.
- Add unit tests for generic implementation of `sqrt`.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D118173
Make logf function correctly rounded for all rounding modes.
Reviewed By: sivachandra, zimmermann6, santoshn, jpl169
Differential Revision: https://reviews.llvm.org/D118149
Based on RLIBM implementation similar to logf and log2f. Most of the exceptional inputs are the exact powers of 10.
Reviewed By: sivachandra, zimmermann6, santoshn, jpl169
Differential Revision: https://reviews.llvm.org/D118093
in all the other `add_tablegen` calls, the project name is so transformed so it
can be a prefix of a CMake variable. I think it is better to do do that here
too for consistency.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117979
This is an optimization that using a single CPU instruction on supported
architectures (amd64 and aarch64, but possibly others) to replace what was
previously an iterative look-up-table algorithm.
Originally I suggested using inline assembly for this in
https://reviews.llvm.org/D117584.
Reviewed By: lntue, sivachandra
Differential Revision: https://reviews.llvm.org/D117684
Add to log2f 2 more exceptional cases got when not using fma for polyeval.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117812
The floating point tricks used to get rounding mode require -frounding-math flag, which behaves differently on aarch64. Reverting back to use get_round instead.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117824
Update the rounding logic for generic hypot function so that it will round correctly with all rounding modes.
Reviewed By: sivachandra, zimmermann6
Differential Revision: https://reviews.llvm.org/D117590
Use hexadecimal floats with C++17 instead of as_double as floating point constant initializations.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117628
This is the original patch in my GNUInstallDirs series, now last to merge as the final piece!
It arose as a new draft of D28234. I initially did the unorthodox thing of pushing to that when I wasn't the original author, but since I ended up
- Using `GNUInstallDirs`, rather than mimicking it, as the original author was hesitant to do but others requested.
- Converting all the packages, not just LLVM, effecting many more projects than LLVM itself.
I figured it was time to make a new revision.
I have used this patch series (and many back-ports) as the basis of https://github.com/NixOS/nixpkgs/pull/111487 for my distro (NixOS), which was merged last spring (2021). It looked like people were generally on board in D28234, but I make note of this here in case extra motivation is useful.
---
As pointed out in the original issue, a central tension is that LLVM already has some partial support for these sorts of things. Variables like `COMPILER_RT_INSTALL_PATH` have already been dealt with. Variables like `LLVM_LIBDIR_SUFFIX` however, will require further work, so that we may use `CMAKE_INSTALL_LIBDIR`.
These remaining items will be addressed in further patches. What is here is now rote and so we should get it out of the way before dealing more intricately with the remainder.
Reviewed By: #libunwind, #libc, #libc_abi, compnerd
Differential Revision: https://reviews.llvm.org/D99484
This is the original patch in my GNUInstallDirs series, now last to merge as the final piece!
It arose as a new draft of D28234. I initially did the unorthodox thing of pushing to that when I wasn't the original author, but since I ended up
- Using `GNUInstallDirs`, rather than mimicking it, as the original author was hesitant to do but others requested.
- Converting all the packages, not just LLVM, effecting many more projects than LLVM itself.
I figured it was time to make a new revision.
I have used this patch series (and many back-ports) as the basis of https://github.com/NixOS/nixpkgs/pull/111487 for my distro (NixOS), which was merged last spring (2021). It looked like people were generally on board in D28234, but I make note of this here in case extra motivation is useful.
---
As pointed out in the original issue, a central tension is that LLVM already has some partial support for these sorts of things. Variables like `COMPILER_RT_INSTALL_PATH` have already been dealt with. Variables like `LLVM_LIBDIR_SUFFIX` however, will require further work, so that we may use `CMAKE_INSTALL_LIBDIR`.
These remaining items will be addressed in further patches. What is here is now rote and so we should get it out of the way before dealing more intricately with the remainder.
Reviewed By: #libunwind, #libc, #libc_abi, compnerd
Differential Revision: https://reviews.llvm.org/D99484
strdup needs either scudo enabled or fullbuild disabled, this properly
adds the second condition
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D117138
Add an extra argument for rounding mode to EXPECT_MPFR_MATCH and ASSERT_MPFR_MATCH macros.
Reviewed By: sivachandra, michaelrj
Differential Revision: https://reviews.llvm.org/D116777
Some functions were added to x86_64 that were untested on Aarch64. Now
that I've had an opportunity to test them, they all work on Aarch64 with
the minor formatting change included.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D117146
Specifically, mmap and munmap have been moved to the default build list
of entrypoints. To support this, certain deps and includes have been
adjusted. The use of errno in some cases has been updated.
Add mmap and munmap to the linux aarch64 entrypoint list as the first
user of these syscalls.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D116949
Other threads related tests have been using the API that is tested here
without any problems. The main reason for disabling the test has also been
fixed many months ago.
A variable was named in a way that doesn't match the format. This patch
renames it to match the format.
Differential Revision: https://reviews.llvm.org/D116228
The Eisel-Lemire algorithm is an effecient way to handle converting to
floating point numbers from strings, but in its base form it only
supports up to 64 bit floating point numbers. This adds an
implementation to handle long doubles.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D115280
I missed two instances of "SetUp" being replaced by "set_up" and
"TearDown" being replaced by "tear_down" when finalizing the formatting
change. This fixes that.
Differential Revision: https://reviews.llvm.org/D116178
Apply the formatting rules that were applied to the libc/src directory
to the libc/test directory, as well as the files in libc/utils that are
included by the tests. This does not include automated enforcement.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D116127
Run performance tests in denormal and normal ranges separately and show more detailed results.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D116112
previously, memcpy could get stuck in a loop, calling __builtin_memcpy
which would redirect to itself. This patch removes that path.
Reviewed By: gchatelet, sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D115542
The default isnan returns an int, and hence failing the EXPECT_TRUE tests.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D115892
A small collection of utils called osutils has been added. These utils
are now used in loader tests instead of the equivalent entrypoints.
The loader can now be built and tested without depending on any entrypoint.
In a follow up change, the relevent entrypoints will be updated to use the
newly added osutils.
Reviewed By: lntue, michaelrj
Differential Revision: https://reviews.llvm.org/D115655
Due to the differences between the types of long double, this function
is effectively three functions in one. This patch adds basic support for
the types of long double, although it's just using the fast path and the
fallback for the moment. I still need to implement a version of
Eisel-Lemire for performance, but the existing algorithms should be
correct.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D113710
Add ADD_FMA_FLAG macro to add -mfma flag to functions that requires it.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D115572
- Use intrinsics for x86-64 fma
- Optimize PolyEval for x86-64 with degree 3 & 5 polynomials.
- There might be a slight loss of accuracy compared to Horner's scheme due to usages of higher powers x^2 and x^3 in the computations.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D115347
Generation of the .yaml has been removed to prevent lint from
running with every ninja invocation. The new .clang-tidy file is copied
to the libc build directory so that generated files also get checked.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D115405
adds the .yaml files clang-tidy generates as byproducts, which means
that they will be updated properly and cleaned by `ninja -t clean`
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D115290
This patch applies the lint rules described in the previous patch. There
was also a significant amount of effort put into manually fixing things,
since all of the templated functions, or structs defined in /spec, were
not updated and had to be handled manually.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D114302
This commit changes the clang-tidy rules for LLVM-libc to follow the new
format. The next commit applies these rules to the codebase.
The rules are as follows:
CamelCase for classes
lower_case for variables
lower_case for functions
UPPER_CASE for constexpr variables
There are also some exceptions, but the most important one is that any
function or variable that starts with an underscore is exempt from the
formatting.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D114301
We want to simplify the build system and rely on code to do the implementation selection.
This is in preparation of adding a Bazel configuration (D114712).
Differential Revision: https://reviews.llvm.org/D115034
Fix a bug in MPFRUtils making ULP values off by 2^(-mantissaWidth) and incorrect eps for denormal numbers.
Differential Revision: https://reviews.llvm.org/D114878
Up until now, all references to `errno` were marked with `NOLINT`, since
it was technically calling an external function. This fixes the lint
rules so that `errno`, as well as `malloc`, `calloc`, `realloc`, and
`free` are all allowed to be called as external functions. All of the
relevant `NOLINT` comments have been removed, and the documentation has
been updated.
Reviewed By: sivachandra, lntue, aaron.ballman
Differential Revision: https://reviews.llvm.org/D113946
This patch enables the benchmarking of `memmove`.
Ideally, this should be submitted before D114637.
Differential Revision: https://reviews.llvm.org/D114694
Fix the fact that previously strtof/d/ld would only accept a NaN as
having parentheses if the thing in the parentheses was a valid number,
now it will accept any combination of letters and numbers, but will only
put valid numbers in the mantissa.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D113790
Siva Chandra Reddy