Commit Graph
197 Commits
Author SHA1 Message Date
Siva Chandra Reddy 2f4f452f16 [libc] Add a skeleton for C standard condition variable functions.
This patch adds a skeleton as a preparatory step for the next patch which
adds the actual implementations of the condition variable functions.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D108947
2021-09-01 19:41:52 +00:00
Siva Chandra Reddy 0239adac4a [libc] Mark return value of memcpy in strcpy as initialized for msan.
Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D109045
2021-09-01 19:01:25 +00:00
Michael Jones 7f2ce19d1c [libc][nfc][obvious] fix typos in FPUtil
Fix minor typos in FPUtil comments.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D108952
2021-08-30 22:39:02 +00:00
Siva Chandra Reddy 7a2a765745 [libc] Add mtx_destroy which does nothing.
There is not cleanup to be done for the mutex type so mtx_destroy does
nothing.
2021-08-30 20:43:46 +00:00
Siva Chandra Reddy 3383ec5fdd [libc] Ensure the result of the clone syscall is not on stack in thrd_create.
Also, added a call to munmap on error in thrd_create.
2021-08-30 04:35:40 +00:00
Siva Chandra Reddy f7e572b4f4 [libc][NFC] Add a check to catch mismatch in internal and public mutex types. 2021-08-30 04:08:35 +00:00
Siva Chandra Reddy 004c7b1da6 [libc][NFC] Move the mutex implementation into a utility class.
This allows others parts of the libc to use the mutex types without
actually pulling in public function implementations.

Along the way, few cleanups have been done, like using a uniform type to
refer the linux futex word.

Reviewed By: michaelrj

Differential Revision: https://reviews.llvm.org/D108749
2021-08-26 18:49:20 +00:00
Michael Jones 035325275c [libc] add inttypes header
Add inttypes.h to llvm libc. As its first functions strtoimax and
strtoumax are included.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D108736
2021-08-26 18:04:21 +00:00
Michael Jones eff11176c5 [libc] Enable string to integer conversion functions in the default build
Adds atoi, atol, atoll, strtol, strtoll, strtoul, and strtoull to the
list of entrypoints for Windows and aarch64 linux, as well as moving
them out of the LLVM_LIBC_FULL_BUILD condition for x86_64 linux.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D108477
2021-08-23 21:18:14 +00:00
Alfonso Gregory 9cdd4ea06f [libc][NFC] Add explicit casts to ctype functions
Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D106902
2021-08-23 18:17:20 +00:00
Siva Chandra Reddy 8e488c3cc0 [libc] Add a multi-waiter mutex test.
A corresponding adjustment to mtx_lock has also been made.
2021-08-23 05:47:30 +00:00
Siva Chandra Reddy ca6b354229 [libc] Add range reduction functions based on Paine and Hanek algorithm.
These functions will be used in a future patch to implement
trigonometric functions. Unit tests have been added but to the
libc-long-running-tests suite. The unit tests long running because we
compare against MPFR computations performed at 1280 bits of precision.

Some cleanups or elimination of repeated patterns can be done as follow
up changes.

Differential Revision: https://reviews.llvm.org/D104817
2021-08-23 05:18:41 +00:00
Guillaume Chatelet 791d88f35f [libc] Align to 32B instead of 16B for optimized memcmp 2021-08-20 13:09:35 +00:00
Guillaume Chatelet b460534ac7 [libc] Add an optimized version for memcmp
Differential Revision: https://reviews.llvm.org/D108406
2021-08-20 06:40:37 +00:00
Michael Jones bad3168b99 [libc] add atoi, atol, and atoll
This is based on the work done to add strtoll and the other strto
functions. The atoi functions also were added to stdc and
entrypoints.txt.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D108330
2021-08-19 18:02:51 +00:00
Guillaume Chatelet c8f79892af [libc] Add a trivial implementation for bcmp
Differential Revision: https://reviews.llvm.org/D108225
2021-08-19 17:55:16 +00:00
Michael Jones d52f0aeca5 [libc] Add strtol, strtoul, and strtoull
Updates the internal string conversion function so that it
uses the new Limits.h added in a previous commit for max and min values,
and has a templated type. This makes implementing the other strto*
functions very simple.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D107999
2021-08-17 21:05:37 +00:00
Guillaume Chatelet 83457d398d [libc] dedup handling of size 4 for memset 2021-08-16 22:29:10 +00:00
Guillaume Chatelet 8e4efad991 [libc] Optimize Loop strategy
Since the precondition for loop is `size >= T::kSize` we always expect
at least one run of the loop. This patch transforms the for-loop into a
do/while-loop which saves at least one test.

We also add a second template parameter to allow the Tail operation to
differ from the loop operation.
2021-08-16 22:17:56 +00:00
Michael Jones b062d639bb [libc] add strtoll function and backend
This change adds the stroll function, but most of the implementation is
in the new file str_conv_utils.h since many of the other integer
conversion functions are implemented through what are effectively calls
to strtoll.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D107792
2021-08-11 23:37:23 +00:00
Michael Jones c120edc7b3 [libc][nfc] move ctype_utils and FPUtils to __support
Some ctype functions are called from other libc functions (e.g. isspace
is used in atoi). By moving ctype_utils.h to __support it becomes easier
to include just the implementations of these functions. For these
reasons the implementation for isspace was moved into
ctype_utils as well.

FPUtils was moved to simplify the build order, and to clarify which
files are a part of the actual libc.

Many files were modified to accomodate these changes, mostly changing
the #include paths.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D107600
2021-08-06 17:29:41 +00:00
Siva Chandra Reddy 381f9affab [libc][NFC] Add dummy errno target to satisfy mixed mode builds.
In mixed mode builds, we should not be including errno as part of
LLVM libc - errno from another library (or the system library) should be
used. But, other entrypoints which use errno list LLVM libc's errno as a
dep ta satisfy the full build mode. So, we add a dummy errno
implementation with empty files to make both mixed mode and full build
mode happy.
2021-07-30 17:42:48 +00:00
Guillaume Chatelet cd2f5d5b49 [libc] rewrite aarch64 memcmp implementation
This patch is simply rearranging the code layout so it's easier to understand.

Differential Revision: https://reviews.llvm.org/D106641
2021-07-29 14:41:12 +00:00
Alfonso Gregory 640ed21cce [libc][NFC] Add noreturn and constexpr qualifiers where appropriate
These functions make it clear to the compiler and user what the intended
behavior is so llvm can make them go as fast as possible.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D106807
2021-07-29 04:50:05 +00:00
Michael Jones c6d03b583b [libc] add strncmp to strings
Add strncmp as a function to strings.h. Also adds unit tests, and adds
strncmp as an entrypoint for all current platforms.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D106901
2021-07-28 21:37:12 +00:00
Alfonso Gregory 0784e62c3c [libc] Fix strtok_r crash when src and *saveptr are both nullptr
While working and testing my refactoring of multiple string functions in libc, I came across a bug that needs to be addressed in a patch on its own: src is checked for nullptr and assigned to *saveptr if it is nullptr. However, saveptr is initially nullptr when it comes to reentry. This could cause a problem if both saveptr and src are null; we need to do the check first and return nullptr if both are nullptr.

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D106885
2021-07-27 21:49:23 +00:00
Guillaume Chatelet 24ffb98f9d [libc] optimize bzero/memset for x86
This is simpy using the x86 optimized elements when targetting x86 cpus.

Differential Revision: https://reviews.llvm.org/D106551
2021-07-23 12:21:46 +00:00
Hedin Garca 049cfc464d [libc] Rename FEnv.h and refactor subsequent files
Because Windows's pathnames are not case sensitive,
to avoid include conflicts between our header file FEnv.h and the
one from the C Standard library, <fenv.h>, the prior file was renamed.
The motive for the relabel came to fix this include error in
TestHelpers.cpp since a conflict arose with a file in the same
directory when #include <fenv.h> was being used.

Reviewed By: sivachandra, aeubanks

Differential Revision: https://reviews.llvm.org/D106470
2021-07-22 00:07:39 +00:00
Andre Vieira 366805ea17 [LIBC] Add an optimized memcmp implementation for AArch64
Differential Revision: https://reviews.llvm.org/D105441
2021-07-07 15:59:14 +01:00
Siva Chandra Reddy 804dc3dcf2 [libc] Clear all exceptions before setting in fesetexceptflag.
Previously, exceptions from the flag were being added. This patch
changes it such that only the exceptions in the flag will be set.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D105085
2021-06-30 17:29:48 +00:00
Siva Chandra Reddy 2e9c75daff [libc] Use __builtin_ctzll instead of __builtin_ctzl in elements_x86.h.
__builtin_ctzl takes an unsigned long argument which need not be 64-bit
long on all platforms. Using __builtin_ctzll, which takes an unsigned
long long argument, ensures that 64-bit values will be handled on a
wider range of platforms.

Without this change, the test corresponding to M512 fails in Windows.

Reviewed By: gchatelet

Differential Revision: https://reviews.llvm.org/D104897
2021-06-25 22:58:13 +00:00
Guillaume Chatelet 87065c0d24 [libc] add benchmarks for memcmp and bzero
Differential Revision: https://reviews.llvm.org/D104511
2021-06-23 14:19:40 +00:00
Guillaume Chatelet 7fff39d9b0 [libc] Add a set of elementary operations
Resubmission of D100646 now making sure that we handle cases were `__builtin_memcpy_inline` is not available.

Original commit message:
Each of these elementary operations can be assembled to support higher order constructs (Overlapping access, Loop, Aligned Loop).
The patch does not compile yet as it depends on other ones (D100571, D100631) but it allows to get the conversation started.

A self-contained version of this code is available at https://godbolt.org/z/e1x6xdaxM
2021-06-16 12:11:45 +00:00
Guillaume Chatelet c3242238b7 Revert "[libc] Add a set of elementary operations"
This reverts commit 4694321fbe.
2021-06-16 11:22:46 +00:00
Guillaume Chatelet 4694321fbe [libc] Add a set of elementary operations
Resubmission of D100646 now making sure that we handle cases were `__builtin_memcpy_inline` is not available.

Original commit message:
Each of these elementary operations can be assembled to support higher order constructs (Overlapping access, Loop, Aligned Loop).
The patch does not compile yet as it depends on other ones (D100571, D100631) but it allows to get the conversation started.

A self-contained version of this code is available at https://godbolt.org/z/e1x6xdaxM
2021-06-16 11:16:24 +00:00
Guillaume Chatelet 2e286f233e Revert "[libc] Add a set of elementary operations"
This reverts commit 8387187c2f.
2021-06-15 15:00:21 +00:00
Guillaume Chatelet 8387187c2f [libc] Add a set of elementary operations
Resubmission of D100646 now making sure that we handle cases were `__builtin_memcpy_inline` is not available.

Original commit message:
Each of these elementary operations can be assembled to support higher order constructs (Overlapping access, Loop, Aligned Loop).
The patch does not compile yet as it depends on other ones (D100571, D100631) but it allows to get the conversation started.

A self-contained version of this code is available at https://godbolt.org/z/e1x6xdaxM
2021-06-15 14:39:04 +00:00
Guillaume Chatelet c11032ad9a Revert "[libc] Add a set of elementary operations"
This reverts commit 454d92ac3b.
2021-06-15 08:01:59 +00:00
Guillaume Chatelet 454d92ac3b [libc] Add a set of elementary operations
Resubmission of D100646 now making sure that we handle cases were `__builtin_memcpy_inline` is not available.

Original commit message:
Each of these elementary operations can be assembled to support higher order constructs (Overlapping access, Loop, Aligned Loop).
The patch does not compile yet as it depends on other ones (D100571, D100631) but it allows to get the conversation started.

A self-contained version of this code is available at https://godbolt.org/z/e1x6xdaxM
2021-06-15 07:57:13 +00:00
Siva Chandra Reddy a58b2827fe [libc] Add hardware implementations of x86_64 sqrt functions. 2021-06-14 21:25:37 +00:00
Guillaume Chatelet ab45c1f21f Revert "[libc] Add a set of elementary operations"
This reverts commit e63f27a3cf.
2021-06-14 09:34:03 +00:00
Guillaume Chatelet e63f27a3cf [libc] Add a set of elementary operations
Each of these elementary operations can be assembled to support higher order constructs (Overlapping access, Loop, Aligned Loop).
The patch does not compile yet as it depends on other ones (D100571, D100631) but it allows to get the conversation started.

Differential Revision: https://reviews.llvm.org/D100646
2021-06-14 09:01:06 +00:00
Tue Ly 4e5f8b4d8d [libc] Add implementation of expm1f.
Use expm1f(x) = exp(x) - 1 for |x| > ln(2).
For |x| <= ln(2), divide it into 3 subintervals: [-ln2, -1/8], [-1/8, 1/8], [1/8, ln2]
and use a degree-6 polynomial approximation generated by Sollya's fpminmax for each interval.
Errors < 1.5 ULPs when we use fma to evaluate the polynomials.

Differential Revision: https://reviews.llvm.org/D101134
2021-06-10 14:58:34 -04:00
Siva Chandra Reddy 7deb5ef44f [libc][NFC] Instead of erroring, skip math targets with missing implementations.
Fixes Aarch64 bot.
2021-05-13 19:22:11 +00:00
Siva Chandra Reddy 861dc75906 [libc] Add x86_64 implementations of double precision cos, sin and tan.
The implementations use the x86_64 FPU instructions. These instructions
are extremely slow compared to a polynomial based software
implementation. Also, their accuracy falls drastically once the input
goes beyond 2PI. To improve both the speed and accuracy, we will be
taking the following approach going forward:
1. As a follow up to this CL, we will implement a range reduction algorithm
which will expand the accuracy to the entire double precision range.
2. After that, we will replace the HW instructions with a polynomial
implementation to improve the run time.

After step 2, the implementations will be accurate, performant and target
architecture independent.

Reviewed By: lntue

Differential Revision: https://reviews.llvm.org/D102384
2021-05-13 19:02:00 +00:00
Guillaume Chatelet 6351993da7 [libc] Simplifies multi implementations
This is a roll forward of D101895 with two additional fixes:

Original Patch description:
> This is a follow up on D101524 which:
>
> - simplifies cpu features detection and usage,
> - flattens target dependent optimizations so it's obvious which implementations are generated,
> - provides an implementation targeting the host (march/mtune=native) for the mem* functions,
> - makes sure all implementations are unittested (provided the host can run them).

Additional fixes:
 - Fix uninitialized ALL_CPU_FEATURES
 - Use non pseudo microarch as it is only supported from Clang 12 on

Differential Revision: https://reviews.llvm.org/D102233
2021-05-12 07:24:53 +00:00
Siva Chandra Reddy 0c64cef894 [libc] Rever "Simplifies multi implementations and benchmarks".
This reverts commit 541f107871 as the bots
are failing with unknown architecture "x86-64-v*". Will let the original
author decide on the right course of action to correct the problem and
reland.
2021-05-10 19:20:27 +00:00
Guillaume Chatelet 541f107871 [libc] Simplifies multi implementations and benchmarks
This is a follow up on D101524 which:
 - simplifies cpu features detection and usage,
 - flattens target dependent optimizations so it's obvious which implementations are generated,
 - provides an implementation targeting the host (march/mtune=native) for the mem* functions,
 - makes sure all implementations are unittested (provided the host can run them),
 - makes sure all implementations are benchmarkable (provided the host can run them).

Differential Revision: https://reviews.llvm.org/D101895
2021-05-10 08:23:30 +00:00
Guillaume Chatelet 7c2ece523d [libc] Normalize LIBC_TARGET_MACHINE
Current implementation defines LIBC_TARGET_MACHINE with the use of CMAKE_SYSTEM_PROCESSOR.
Unfortunately CMAKE_SYSTEM_PROCESSOR is OS dependent and can produce different results.
An evidence of this is the various matchers used to detect whether the architecture is x86.

This patch normalizes LIBC_TARGET_MACHINE and renames it LIBC_TARGET_ARCHITECTURE.
I've added many architectures but we may want to limit ourselves to x86 and ARM.

Differential Revision: https://reviews.llvm.org/D101524
2021-05-05 15:52:42 +00:00
Raman Tenneti a72499e475 [libc] Introduce asctime, asctime_r to LLVM libc
[libc] Introduce asctime, asctime_r to LLVM libc

asctime and asctime_r share the same common code. They call asctime_internal
a static inline function.

asctime uses snprintf to return the string representation in a buffer.
It uses the following format (26 characters is the buffer size) as per
7.27.3.1 section in http://www.open-std.org/jtc1/sc22/wg14/www/docs/n2478.pdf.
The buf parameter for asctime_r shall point to a buffer of at least 26 bytes.

snprintf(buf, 26, "%.3s %.3s%3d %.2d:%.2d:%.2d %d\n",...)

Reviewed By: sivachandra

Differential Revision: https://reviews.llvm.org/D99686
2021-05-03 17:15:00 -07:00