Implements the posix-specified strftime conversions for the default
locale, along with comprehensive unit tests. This reuses a lot of design
from printf, as well as the printf writer.
Roughly based on #111305, but with major rewrites.
This reverts commit bada9220b87e73c0f4a498b82f883e17eda928d1.
Revert "[libc][stdfix] Implement fixed point `countlsfx` functions in llvm-libc (#125356)"
This reverts commit f2a1103b323492160d7d27a1575fbda709b49036.
riscv32 specifically doesn't provide EITHER SYS_poll or SYS_ppoll. We may be
able to reimplement poll in terms of syscalls to SYS_ppoll_time64, but will
leave that as a TODO for the future. (Such as when we want to be able to cross
compile for riscv32).
Link: #125940Fixes: #125118
The existing options for bin→dec float conversion are all based on the
Ryū algorithm, which generates 9 output digits at a time using a table
lookup. For users who can't afford the space cost of the table, the
table-lookup subroutine is replaced with one that computes the needed
table entry on demand, but the algorithm is otherwise unmodified.
The performance problem with computing table entries on demand is that
now you need to calculate a power of 10 for each 9 digits you output.
But if you're calculating a custom power of 10 anyway, it's easier to
just compute one, and multiply the _whole_ mantissa by it.
This patch adds a header file alongside `float_dec_converter.h`, which
replaces the whole Ryū system instead of just the table-lookup routine,
implementing this alternative simpler algorithm. The result is accurate
enough to satisfy (minimally) the accuracy demands of IEEE 754-2019 even
in 128-bit long double. The new float128 test cases demonstrate this by
testing the cases closest to the 39-digit rounding boundary.
In my tests of generating 39 output digits (the maximum number supported
by this algorithm) this code is also both faster and smaller than the
USE_DYADIC_FLOAT version of the existing Ryū code.
Update string_utils' string_length to work with char* or wchar_t*, so that it
may be reusable when implementing wmemchr, wcspbrk, wcsrchr, wcsstr.
Link: #121183
Link: #124027
Co-authored-by: Nick Desaulniers <ndesaulniers@google.com>
---------
Co-authored-by: Tristan Ross <tristan.ross@midstall.com>
implement sys/uio/writev according to POSIX standard. This vectorized IO
API is needed by many logging libraries to achieve atomic logging
multiple strings.
Keep framepointers enabled by default for the default baremetal libc
builds.
Frame pointers help unwind the stack and unwinding without frame pointer
is complex and increaseis the code size. This code size increase is
potentially larger than the savings achieved by disabling frame
pointers. Retaining the original behavior of retaining frame pointers as
the default behavior.
Summary:
This is a holdover from when these targets were merged. They're
basically the same but there's no reason they should be treated as
identical. I think we will live with a little duplication.
Summary:
This was originally a hacked together function that served to just
implement some features for OpenMP. That has been moved into OpenMP
itself now that we have exported RPC properly. This can now be deleted.
docgen relies on the convention that we have a file foo.cpp in
libc/src/\<header\>/. Because the above functions weren't in libc/src/strings/
but rather libc/src/string/, docgen could not find that we had implemented
these.
Rather than add special carve outs to docgen, let's fix up our sources for
these 7 functions to stick with the existing conventions the rest of the
codebase follows.
Link: #118860Fixes: #118875
Add a `clock_gettime` emulation layer and use it to implement the `time`
entrypoint.
For windows, the monotonic clock is emulated using `QPC`.
The realtime clock is emulated using `GetSystemTimePreciseAsFileTime`.
Thanks to the effort of @RoseZhang03 and @aaryanshukla under the
guidance of
@michaelrj-google and @amykhuang, we now have newhdrgen and no longer
have a
dependency on TableGen and thus LLVM in order to start bootstrapping a
full
build.
This PR removes:
- LIBC_HDRGEN_EXE; the in tree newhdrgen is the only hdrgen that can be
used.
- LIBC_USE_NEW_HEADER_GEN; newhdrgen is the default and only option.
- LIBC_HDRGEN_ONLY; there is no need to have a distinct build step for
old
hdrgen.
- libc-api-test and libc-api-test-tidy build targets.
- Deletes all .td files.
It does not rename newhdrgen to just hdrgen. Will follow up with a
distinct PR
for that.
Link: #117209
Link: #117254Fixes: #117208
