Previously, the test failed due to isnan() and isinf() not being
defined.
This patch follows other tests in the same directory and calls isnan and
isinf from the FBits class.
---------
Co-authored-by: OverMighty <its.overmighty@gmail.com>
Main algorithm:
The Taylor series expansion of `asin(x)` is:
```math
\begin{align*}
asin(x) &= x + x^3 / 6 + 3x^5 / 40 + ... \\
&= x \cdot P(x^2) \\
&= x \cdot P(u) &\text{, where } u = x^2.
\end{align*}
```
For the fast path, we perform range reduction mod 1/64 and use degree-7
(minimax + Taylor) polynomials to approximate `P(x^2)`.
When `|x| >= 0.5`, we use the transformation:
```math
u = \frac{1 + x}{2}
```
and apply half-angle formula to reduce `asin(x)` to:
```math
\begin{align*}
asin(x) &= sign(x) \cdot \left( \frac{\pi}{2} - 2 \cdot asin(\sqrt{u}) \right) \\
&= sign(x) \cdot \left( \frac{\pi}{2} - 2 \cdot \sqrt{u} \cdot P(u) \right).
\end{align*}
```
Since `0.5 <= |x| <= 1`, `|u| <= 0.5`. So we can reuse the polynomial
evaluation of `P(u)` when `|x| < 0.5`.
For the accurate path, we redo the computations in 128-bit precision
with degree-15 (minimax + Taylor) polynomials to approximate `P(u)`.
- Merges `BinaryOpSingleOutputPerf.h` and
`SingleInputSingleOutputPerf.h` files into a unified `PerfTest.h` and
update all performance tests to use this.
- Improve the output printed to log file for tests.
- Removes unused `run_diff` method and redundant `run_perf` call in
`BINARY_INPUT_SINGLE_OUTPUT_PERF_EX` (previously
`BINARY_OP_SINGLE_OUTPUT_PERF_EX`)
- Change `BINARY_INPUT_SINGLE_OUTPUT_PERF_EX` and
`SINGLE_INPUT_SINGLE_OUTPUT_PERF` to not define `main`
`((23U + 127U) << 23) + 1` evaluates to `(2^23)+1` as opposed to `2^24`,
so should instead be `(24U + 127U) << 23`. Additionally, range for both
inputs is inclusive of STOP. The comments have been updated reflecting
these changes.
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 reverts commit 1e6e845d49a336e9da7ca6c576ec45c0b419b5f6 because it
changed the 1st parameter of adjust() to be unsigned, but libc itself
calls adjust() with a negative argument in align_backward() in
op_generic.h.
Use a combination of polynomial approximation and Newton-Raphson
iterations in 64-bit and 128-bit integers to improve the performance of
sqrtf128. The correct rounding is provided by squaring the result and
comparing it with the argument.
Performance improvement using the newly added perf test:
- My function = the improved implementation from this PR
- Other function = current implementation using
`libc/src/__support/FPUtil/generic/sqrt.h`
```
Performance tests with inputs in denormal range:
-- My function --
Total time : 1260765265 ns
Average runtime : 125.951 ns/op
Ops per second : 7939623 op/s
-- Other function --
Total time : 7160726518 ns
Average runtime : 715.357 ns/op
Ops per second : 1397902 op/s
-- Average runtime ratio --
Mine / Other's : 0.176067
Performance tests with inputs in normal range:
-- My function --
Total time : 373003808 ns
Average runtime : 37.2631 ns/op
Ops per second : 26836189 op/s
-- Other function --
Total time : 7353398916 ns
Average runtime : 734.605 ns/op
Ops per second : 1361275 op/s
-- Average runtime ratio --
Mine / Other's : 0.0507254
```
---------
Co-authored-by: Alexei Sibidanov <sibid@uvic.ca>
Also, update the unit tests that were checking for SIGSEGV to not check for a
specific signal.
To further improve this check, it may be worth:
- renaming the configuration option/macro/docs to be clearer about intent.
- swap __builtin_trap for __builtin_unreachable, removing the preprocessor
variants of LIBC_CRASH_ON_NULLPTR, then unconditionally using
`-fsanitize=unreachable -fsanitize-trap=unreachable` in cmake flags when
LIBC_ADD_NULL_CHECKS is enabled.
- building with `-fno-delete-null-pointer-checks` when LIBC_ADD_NULL_CHECKS (or
when some larger yet to be added hardening config) is enabled.
Link: #111546
Found while trying to consolidate our command line flags between tests and
underlying object files.
error: extra ';' after member function definition [-Werror,-Wextra-semi]
Link: #119281
Make sure to clear out all FE_ALL_EXCEPT bits both before and after
invoking function under test -- otherwise the very first check for the
exception bits in the unit test may fail due to bits set prior to test
invocation.
- migrate more `-O3` to `${libc_opt_high_flag}`
- workaround a issue with `LLP64` in test. The overflow testing is
guarded by a constexpr but the literal overflow itself will still
trigger warnings.
Notice that for math smoke test, for some reasons, the
`${libc_opt_high_flag}` will be passed into `lld-link` which confuses
the linker so there are still some warnings leftover there. I can
investigate more when I have time.
`long double` is haunted on most architectures, but it is especially so on
i386-linux-gnu. While have 80b of significant data, on i386-linux-gnu this type
has 96b of storage.
Fixes for supporting printf family of conversions for `long double` on
i386-linux-gnu. This allows the libc-stdlib-tests and libc_stdio_unittests
ninja target tests to pass on i386-linux-gnu.
Fixes: #110894
Link: #93709
Co-authored-by: Michael Jones <michaelrj@google.com>
I normally run my cmake with LIBC_CMAKE_VERBOSE_LOGGING set to ON so I
can debug build issues more easily. One of the effects of this is I see
which tests/entrypoints are skipped on my machine. This patch fixes up
the tests and entrypoints that were skipped, but easily fixed. These
were:
libc.src.pthread.pthread_spin_destroy
libc.src.pthread.pthread_spin_init
libc.src.pthread.pthread_spin_lock
libc.src.pthread.pthread_spin_trylock
libc.src.pthread.pthread_spin_unlock
(entrypoints were just missing)
libc.src.wchar.btowc
(I forgot to finish it)
libc.test.src.sys.statvfs.linux.statvfs_test
libc.test.src.sys.statvfs.linux.fstatvfs_test
(Incorrect includes for rmdir, needed some cleanup)
libc.test.integration.src.unistd.execve_test
(wrong dep for errno)
libc.test.src.math.smoke.fmaf_test
(add_fp_unittest doesn't support flags)
libc.test.src.stdio.scanf_core.converter_test
(needed to be moved away from string_reader, further cleanup needed)
- 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()`
MPFR functionality is provided by the MPFRWrapper instead, and the direct "mpfr.h" inclusion is not needed - this test doesn't rely on it (similar to its sibling libc/test/src/math/exhaustive/cospif_test.cpp that doesn't have it).
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>
