Fixes incorrect logic that went unnoticed until the function was tested
with output and input types that have the same underlying floating-point
format.
This PR aims to add the groundwork to test the precision of libc complex
functions against MPC. I took `cargf` as a test to verify that the infra
works fine.
- Implementation of `tan` for 16-bit floating point inputs scaled by pi.
i.e,. `tanpif16()`
- Implementation of Tanpi in MPFRWrapper for MPFR versions < 4.2
- Exhaustive tests for `tanpif16()`
Implementation of `cos` for half precision floating point inputs scaled
by pi (i.e., `cospi`), correctly rounded for all rounding modes.
---------
Co-authored-by: OverMighty <its.overmighty@gmail.com>
- added all variations of ffma and fdiv
- will add all new headers into yaml for next patch
- only fsub is left then all basic operations for float is complete
---------
Co-authored-by: OverMighty <its.overmighty@gmail.com>
Fixes https://github.com/llvm/llvm-project/issues/92874
Algorithm: Let `x = (-1)^s * 2^e * (1 + m)`.
- Step 1: Range reduction: reduce the exponent with:
```
y = cbrt(x) = (-1)^s * 2^(floor(e/3)) * 2^((e % 3)/3) * (1 + m)^(1/3)
```
- Step 2: Use the first 4 bit fractional bits of `m` to look up for a
degree-7 polynomial approximation to:
```
(1 + m)^(1/3) ~ 1 + m * P(m).
```
- Step 3: Perform the multiplication:
```
2^((e % 3)/3) * (1 + m)^(1/3).
```
- Step 4: Check for exact cases to prevent rounding and clear
`FE_INEXACT` floating point exception.
- Step 5: Combine with the exponent and sign before converting down to
`float` and return.
I also fixed a comment in sinpif.cpp in the first commit. Should this be
included in this PR?
All tests were passed, including the exhaustive test.
CC: @lntue
In full build mode, the fuzzing tests fail to build. This PR disabled MPFR related tests in full build
```
[2/4] Building CXX object projects/libc/fuzzing/stdio/CMakeFiles/libc.fuzzing.stdio.printf_float_conv_fuzz.dir/printf_float_conv_fuzz.cpp.o
FAILED: projects/libc/fuzzing/stdio/CMakeFiles/libc.fuzzing.stdio.printf_float_conv_fuzz.dir/printf_float_conv_fuzz.cpp.o
/usr/bin/clang++ -DLIBC_NAMESPACE=__llvm_libc_19_0_0_git -I/home/schrodingerzy/Documents/llvm/llvm-project/build/projects/libc/fuzzing/stdio -I/home/schrodingerzy/Documents/llvm/llvm-project/libc/fuzzing/stdio -I/home/schrodingerzy/Documents/llvm/llvm-project/libc -isystem /home/schrodingerzy/Documents/llvm/llvm-project/build/projects/libc/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -fsanitize=fuzzer -O2 -g -DNDEBUG -std=c++17 -MD -MT projects/libc/fuzzing/stdio/CMakeFiles/libc.fuzzing.stdio.printf_float_conv_fuzz.dir/printf_float_conv_fuzz.cpp.o -MF projects/libc/fuzzing/stdio/CMakeFiles/libc.fuzzing.stdio.printf_float_conv_fuzz.dir/printf_float_conv_fuzz.cpp.o.d -o projects/libc/fuzzing/stdio/CMakeFiles/libc.fuzzing.stdio.printf_float_conv_fuzz.dir/printf_float_conv_fuzz.cpp.o -c /home/schrodingerzy/Documents/llvm/llvm-project/libc/fuzzing/stdio/printf_float_conv_fuzz.cpp
In file included from /home/schrodingerzy/Documents/llvm/llvm-project/libc/fuzzing/stdio/printf_float_conv_fuzz.cpp:19:
In file included from /home/schrodingerzy/Documents/llvm/llvm-project/libc/utils/MPFRWrapper/mpfr_inc.h:21:
In file included from /usr/include/mpfr.h:53:
In file included from /usr/include/gmp.h:35:
In file included from /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/iosfwd:38:
In file included from /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/bits/requires_hosted.h:31:
In file included from /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/x86_64-pc-linux-gnu/bits/c++config.h:679:
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/x86_64-pc-linux-gnu/bits/os_defines.h:44:5: error: function-like macro '__GLIBC_PREREQ' is not defined
44 | #if __GLIBC_PREREQ(2,15) && defined(_GNU_SOURCE)
| ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/x86_64-pc-linux-gnu/bits/os_defines.h:55:5: error: function-like macro '__GLIBC_PREREQ' is not defined
55 | #if __GLIBC_PREREQ(2, 26) \
| ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/x86_64-pc-linux-gnu/bits/os_defines.h:66:6: error: function-like macro '__GLIBC_PREREQ' is not defined
66 | # if __GLIBC_PREREQ(2, 27)
| ^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/x86_64-pc-linux-gnu/bits/os_defines.h:78:6: error: function-like macro '__GLIBC_PREREQ' is not defined
78 | # if __GLIBC_PREREQ(2, 34)
| ^
In file included from /home/schrodingerzy/Documents/llvm/llvm-project/libc/fuzzing/stdio/printf_float_conv_fuzz.cpp:19:
In file included from /home/schrodingerzy/Documents/llvm/llvm-project/libc/utils/MPFRWrapper/mpfr_inc.h:21:
In file included from /usr/include/mpfr.h:53:
In file included from /usr/include/gmp.h:35:
In file included from /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/iosfwd:42:
In file included from /usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/bits/postypes.h:40:
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:64:11: error: no member named 'mbstate_t' in the global namespace
64 | using ::mbstate_t;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:143:11: error: no member named 'btowc' in the global namespace
143 | using ::btowc;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:144:11: error: no member named 'fgetwc' in the global namespace
144 | using ::fgetwc;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:145:11: error: no member named 'fgetws' in the global namespace
145 | using ::fgetws;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:146:11: error: no member named 'fputwc' in the global namespace
146 | using ::fputwc;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:147:11: error: no member named 'fputws' in the global namespace
147 | using ::fputws;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:148:11: error: no member named 'fwide' in the global namespace
148 | using ::fwide;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:149:11: error: no member named 'fwprintf' in the global namespace
149 | using ::fwprintf;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:150:11: error: no member named 'fwscanf' in the global namespace
150 | using ::fwscanf;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:151:11: error: no member named 'getwc' in the global namespace
151 | using ::getwc;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:152:11: error: no member named 'getwchar' in the global namespace
152 | using ::getwchar;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:153:11: error: no member named 'mbrlen' in the global namespace
153 | using ::mbrlen;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:154:11: error: no member named 'mbrtowc' in the global namespace
154 | using ::mbrtowc;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:155:11: error: no member named 'mbsinit' in the global namespace
155 | using ::mbsinit;
| ~~^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/13.2.1/../../../../include/c++/13.2.1/cwchar:156:11: error: no member named 'mbsrtowcs' in the global namespace
156 | using ::mbsrtowcs;
| ~~^
fatal error: too many errors emitted, stopping now [-ferror-limit=]
```
Context: https://github.com/llvm/llvm-project/pull/87017
- Add proxy header `libc/hdr/math_macros.h` that will:
- include `<math.h>` in overlay mode,
- include `"include/llvm-libc-macros/math-macros.h"` in full build mode.
- Its corresponding CMake target `libc.hdr.math_macros` will only depend
on `libc.include.math` and `libc.include.llvm-libc-macros.math_macros`
in full build mode.
- Replace all `#include "include/llvm-libc-macros/math-macros.h"` with
`#include "hdr/math_macros.h"`.
- Add dependency to `libc.hdr.math_macros` CMake target when using
`add_fp_unittest`.
- Update the remaining dependency.
- Update bazel overlay: add `libc:hdr_math_macros` target, and replacing
all dependency on `libc:llvm_libc_macros_math_macros` with
`libc:hdr_math_macros`.
Implements the functions `roundeven()`, `roundevenf()`, `roundevenl()`
from the roundeven family of functions introduced in C23. Also
implements `roundevenf128()`.
We compute atan2f(y, x) in 2 stages:
- Fast step: perform computations in double precision , with relative
errors < 2^-50
- Accurate step: if the result from the Fast step fails Ziv's rounding
test, then we perform computations in double-double precision, with
relative errors < 2^-100.
On Ryzen 5900X, worst-case latency is ~ 200 clocks, compared to average
latency ~ 60 clocks, and average reciprocal throughput ~ 20 clocks.
Reland of #84991
A downstream overlay mode user ran into issues with the isnan macro not
working in our sources with a specific libc configuration. This patch
replaces the last direct includes of math.h with our internal
math_macros.h, along with the necessary build system changes.
