The implementation currently ignores all spawn attributes. Support for
them will be added in future changes.
A simple allocator for integration tests has been added so that the
integration test for posix_spawn can use the
posix_spawn_file_actions_add* functions.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D135752
These headers are uncommonly used, and from extensions, but some basic
support is needed. Macros have been added where available.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D135731
The isatty function uses the side effects of an ioctl call to determine
if a specific file descriptor is a terminal. I chose TIOCGETD (get line
discipline of terminal) because it didn't require any new structs.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D135618
The sysconf function has many options, this patch adds the basic funtion
and the pagesize option. More options will be added in future patches.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D135409
The logic for strsignal and strerror is very similar, so I've moved them
both to use a shared utility (MessageMapper) for the basic
functionality.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D135322
I've implemente the gnu variant of strerror_r since that seems to be the
one more relevant to what we're trying to do.
Differential Revision: https://reviews.llvm.org/D135227
Without this fix, the declaration in sched.h will not have the "__" prefix and
will cause a compile failure.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D135286
Add the macro CPU_COUNT as well as a backing function to implement the
functionality.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D135179
This provides the reference implementation of rand and srand. In future
this will likely be upgraded to something that supports full ints.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D135187
A very simple and minimal implementation of fork is added. Future
changes will add more functionality to satisfy POSIX and Linux
requirements.
An implementation of wait and a few support macros in sys/wait.h
have also been added to help with testing the fork function.
Reviewed By: lntue, michaelrj
Differential Revision: https://reviews.llvm.org/D135131
Add the syscall wrapper function and tests. It's implemented using a
macro to guarantee the minimum number of arguments.
Reviewed By: sivachandra, lntue
Differential Revision: https://reviews.llvm.org/D134919
They were disabled because we were including linux/signal.h from our
signal.h. Linux's signal.h is not designed to be included from user
programs as it causes a lot of non-standard name pollution. Also, it is
not self-contained. This change defines types and macros relevant for
signal related syscalls within libc's headers and removes inclusion of
Linux headers.
This patch enables the funtions only for x86_64. They will be enabled
for aarch64 also in a follow up patch after testing.
Reviewed By: abrachet, lntue
Differential Revision: https://reviews.llvm.org/D134567
The existing thrd_once function has been refactored so that the
implementation can be shared between thrd_once and pthread_once
functions.
Reviewed By: michaelrj
Differential Revision: https://reviews.llvm.org/D134716
Tested:
Limited unit test: This makes a call and checks that no error was
returned, but we currently don't have the ability to ensure that
time has elapsed as expected.
Co-authored-by: Jeff Bailey <jeffbailey@google.com>
Reviewed By: sivachandra, jeffbailey
Differential Revision: https://reviews.llvm.org/D134095
Implement exp10f function correctly rounded to all rounding modes.
Algorithm: perform range reduction to reduce
```
10^x = 2^(hi + mid) * 10^lo
```
where:
```
hi is an integer,
0 <= mid * 2^5 < 2^5
-log10(2) / 2^6 <= lo <= log10(2) / 2^6
```
Then `2^mid` is stored in a table of 32 entries and the product `2^hi * 2^mid` is
performed by adding `hi` into the exponent field of `2^mid`.
`10^lo` is then approximated by a degree-5 minimax polynomials generated by Sollya with:
```
> P = fpminimax((10^x - 1)/x, 4, [|D...|], [-log10(2)/64. log10(2)/64]);
```
Performance benchmark using perf tool from the CORE-MATH project on Ryzen 1700:
```
$ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh exp10f
GNU libc version: 2.35
GNU libc release: stable
CORE-MATH reciprocal throughput : 10.215
System LIBC reciprocal throughput : 7.944
LIBC reciprocal throughput : 38.538
LIBC reciprocal throughput : 12.175 (with `-msse4.2` flag)
LIBC reciprocal throughput : 9.862 (with `-mfma` flag)
$ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh exp10f --latency
GNU libc version: 2.35
GNU libc release: stable
CORE-MATH latency : 40.744
System LIBC latency : 37.546
BEFORE
LIBC latency : 48.989
LIBC latency : 44.486 (with `-msse4.2` flag)
LIBC latency : 40.221 (with `-mfma` flag)
```
This patch relies on https://reviews.llvm.org/D134002
Reviewed By: orex, zimmermann6
Differential Revision: https://reviews.llvm.org/D134104
Implement acosf function correctly rounded for all rounding modes.
We perform range reduction as follows:
- When `|x| < 2^(-10)`, we use cubic Taylor polynomial:
```
acos(x) = pi/2 - asin(x) ~ pi/2 - x - x^3 / 6.
```
- When `2^(-10) <= |x| <= 0.5`, we use the same approximation that is used for `asinf(x)` when `|x| <= 0.5`:
```
acos(x) = pi/2 - asin(x) ~ pi/2 - x - x^3 * P(x^2).
```
- When `0.5 < x <= 1`, we use the double angle formula: `cos(2y) = 1 - 2 * sin^2 (y)` to reduce to:
```
acos(x) = 2 * asin( sqrt( (1 - x)/2 ) )
```
- When `-1 <= x < -0.5`, we reduce to the positive case above using the formula:
```
acos(x) = pi - acos(-x)
```
Performance benchmark using perf tool from the CORE-MATH project on Ryzen 1700:
```
$ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh acosf
GNU libc version: 2.35
GNU libc release: stable
CORE-MATH reciprocal throughput : 28.613
System LIBC reciprocal throughput : 29.204
LIBC reciprocal throughput : 24.271
$ CORE_MATH_PERF_MODE="rdtsc" ./perf.sh asinf --latency
GNU libc version: 2.35
GNU libc release: stable
CORE-MATH latency : 55.554
System LIBC latency : 76.879
LIBC latency : 62.118
```
Reviewed By: orex, zimmermann6
Differential Revision: https://reviews.llvm.org/D133550
