This script+config should help us generate more consistent documentation wrt.
what we currently support or not.
As an example usage:
$ ./libc/utils/docgen/docgen.py fenv.h
Will spit out an RST formatted table that can be copy+pasted into our docs.
The config is not filled out entirely, but doing so and then updating our docs
would be great beginner bugs for new contributors.
Having python+json generate things like docs, or headers (as imagined in
https://github.com/nickdesaulniers/llvm-project/tree/hdr-gen2) is perhaps
easier to work with than tablegen, and doesn't introduce a dependency on a host
tool that needs to be compiled from llvm sources before building the rest of
the libc. This can probably be merged with whatever we end up doing to replace
libc-hdrgen.
Please use
https://llvm.org/docs/CodingStandards.html#python-version-and-source-code-formatting
for keeping this file formatted.
Implements the functions `roundeven()`, `roundevenf()`, `roundevenl()`
from the roundeven family of functions introduced in C23. Also
implements `roundevenf128()`.
Re-organizes the tables that listed libc's support for math functions,
and adds two new columns to the tables indicating where the respective
function definitions and error handling methods are located in the C23
standard draft WG14-N3096.
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.
Fixes#86546 and removes the macro `LIBC_HAS_BUILTIN`. This was
necessary to support older compilers that did not support
`__has_builtin`. All of the compilers we support already have this
builtin.
See: https://libc.llvm.org/compiler_support.html
All uses now use `__has_builtin` directly
cc @nickdesaulniers
Summary:
Currently we print `null` for the null pointer in a `%s` expression.
Although it's not defined by the standard, other implementations choose
to use `(null)` to indicate this. We also currently print `(nullptr)` so
I think it's more consistent to use parens in both cases.
Continuing #84689, this one required more changes than the others, so I
am making it a separate PR.
Extends some stuff in `str_to_float.h`, `str_to_integer.h` to work on
types wider than `unsigned long long` and `uint64_t`.
cc @lntue for review.
- Allow `FMod` template to have different computational types and make
it work for 80-bit long double.
- Switch to use `uint64_t` as the intermediate computational types for
`float`, significantly reduce the latency of `fmodf` when the exponent
difference is large.
Summary:
After the overhaul of the GPU build the documentation pages were a
little stale. This updates them with more in-depth information on
building the GPU runtimes and using them. Specifically using them goes
through the differences between the offloading and direct compilation
modes.
As encountered with <sys/queue.h>, we need a policy for how to handle
implementing functions that users need, but has no specific standard. In
that case, we should treat existing implementations as the standard and
try to match their behavior as best as possible.
This patch adds the r, R, k, and K conversion specifiers to printf, with
accompanying tests. They are guarded behind the
LIBC_COPT_PRINTF_DISABLE_FIXED_POINT flag as well as automatic fixed
point support detection.