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
This reverts commit 39e9f5d368.
Reverting, as we needed to re-revert the benchmarks move because it was
causing a build failure in the Fuchsia bots due to the way they consume
libcxx's CMakeLists. I want to make sure I understand where the fix
should be for that. After that, I'll incorporate the change here in the
re-reland.
Update binaryExpTofloat so that it will round correctly for long inputs when converting hexadecimal strings to floating points.
Differential Revision: https://reviews.llvm.org/D113815
This reverts commit e7568b68da and relands
c6f7b720ec.
The culprit was: missed that libc also had a dependency on one of the
copies of `google-benchmark`
Also opportunistically fixed indentation from prev. change.
Differential Revision: https://reviews.llvm.org/D112012
Combine two loops in decimalStringToFloat and hexadecimalStringToFloat that extract the digits and re-arrange them a little bit. This slightly improves the performance of strtof and strtod:
Running libc_str_to_float_comparison_test parse-number-fxx-test_data/data/* on my machine (Ryzen 1700)
- with glibc: ~1.92 seconds
- with current implementation: ~1.78 seconds
- with this change: ~1.67 seconds
Differential Revision: https://reviews.llvm.org/D113681
When strtof/d/ld return a subnormal number they may set errno to
ERANGE. This change makes this behavior more consistent by making any
decimal number converting to a subnormal set errno to ERANGE. This
brings it in line with hexadecimals, which currently only set errno to
ERANGE if the number is truncated when converting to a subnormal.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D113626
Add quietNaNMask consts to FloatProperties and make LongDoubleBitsX86
clear the extra bits that aren't set when initializing with an 80 bit
long double.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D113625
Split the code for parsing hexadecimal floating point numbers from the
code for parsing the decimal floating point numbers so that the parsing
can be faster for both of them.
This decreases the time for the benchmark in release mode by about 15%,
which noticeably beats GLibc.
Old version: 2.299s
New version: 1.893s
GLibc: 2.133s
Tests run by running the following command 10 times for each version:
time ~/llvm-project/build/bin/libc_str_to_float_comparison_test ~/parse-number-fxx-test-data/data/*
the parse-number-fxx-test-data-repository is here:
fe94de252c
It's important to build llvm-libc in Release mode for accurate
performance comparisons against glibc (set -DCMAKE_BUILD_TYPE=Release in
your cmake).
You also have to build the libc_str_to_float_comparison_test target.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D113036
Adds an implementation for stpcpy and stpncpy, which are posix extension
functions.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D111913
This allows shipping individual functions without also having to provide
memset or bzero at the expense of bigger functions.
Similar to D113097.
Differential Revision: https://reviews.llvm.org/D113108
Similar to D113097 although not strictly necessary for now. It helps
keeping the same structure for all memory functions.
Differential Revision: https://reviews.llvm.org/D113103
This allows shipping individual functions without also having to provide
`memcpy` at the expense of bigger functions.
Next is to use this `inlined_memcpy` in:
- loader/linux/x86_64/start.cpp
- src/string/memmove.cpp
- src/string/mempcpy.cpp
- src/string/strcpy.cpp
- src/string/strdup.cpp
- src/string/strndup.cpp
Differential Revision: https://reviews.llvm.org/D113097
rename str_conv_utils to str_to_integer to be more
in line with str_to_float.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D113061
We may want to restrict the detected platforms to only `x86_64` and `aarch64`.
There are still custom detection in api.td but I don't think we can handle these:
- config/linux/api.td:205
- config/linux/api.td:199
Differential Revision: https://reviews.llvm.org/D112818
We may want to restrict the detected platforms to only `x86_64` and `aarch64`.
There are still custom detection in api.td but I don't think we can handle these:
- config/linux/api.td:205
- config/linux/api.td:199
Differential Revision: https://reviews.llvm.org/D112818
Add the fast path first described by Clinger [1] with additions by Gay [2].
This speeds up conversion by about 10% by handling numbers with fewer digits
more efficiently.
[1] Clinger WD. How to Read Floating Point Numbers Accurately.
SIGPLAN Not 1990 Jun;25(6):92–101. https://doi.org/10.1145/93548.93557.
[2] Gay DM, Correctly rounded binary-decimal and decimal-binary conversions;
1990. AT&T Bell Laboratories Numerical Analysis Manuscript 90-10.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D112580
The idea is to move all pieces related to the actual libc sources to the
"src" directory. This allows downstream users to ship and build just the
"src" directory.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D112653
malloc, calloc, realloc, and free are all functions that other libc
functions depend on, but are pulled from external sources, instead of
having an internal implementation. This patch adds a way to include
functions like that as entrypoints in the list of external entrypoints,
and includes the malloc functions using this new path.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D112104
Previously, strtol/ll/ul/ull would return a pointer to the end of its
parsing, regardless of if it detected a number. Now it will return a
length of 0 when it doesn't find a number.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D112176
Add an implementation for memccpy and mempcpy. These functions are
posix extensions for the moment.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D111762
This adds strncat to llvm libc. In addition, an error was found with
strcat and that was fixed.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D111583
Also, this adds unit tests to check that limits.h complies with the C
standard.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D110643