They require clang-11 or above for building and hence had to be disabled
as the bots did not have clang-11 or higher. Bots have now been upgraded
so we can enable these functions now.
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
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
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.
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
This patch provides a way to specify the default target cpu optimizations to use when compiling llvm-libc.
This ensures we don't rely on current compiler's default and allows compiling and cross compiling for a particular target.
Differential Revision: https://reviews.llvm.org/D101991
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
[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
Infrastructure needed for setting up the diff binaries has been added.
Along the way, an exhaustive test for sinf and cosf have also been added.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D101276
Aligned copy used to be 'destination aligned' for x86 but this decision was reverted in D93457 where we noticed that it was better for ARM to be 'source aligned'.
More benchmarking confirmed that it can be up to 30% faster to align copy to destination for x86. This Patch offers both implementations and switches x86 back to destination aligned.
It also fixes alignment to 32 byte on x86.
Differential Revision: https://reviews.llvm.org/D101296
This patch mostly adds unittests for `ArrayRef` and `MutableArrayRef`, additionnaly:
- We mimic the behavior of `std::vector` and disallow CV qualified type (`ArrayRef<const X>` is not allowed).
This is to make sure that the type traits are always valid (e.g. `value_type`, `pointer`, ...).
- In the previous implementation `ArrayRef` would define `value_type` as `const T` but this is not correct, it should be `T` for both `MutableArrayRef` and `ArrayRef`.
- We add the `equals` method to ease testing,
- We define the constructor taking an `Array` outside of the base implementation to ensure we match `const Array<T>&` and not `Array<const T>&` in the case of `ArrayRef`.
Differential Revision: https://reviews.llvm.org/D100732
The version of clang installed on the buildbot workers is not able to
compile them. However, the version of gcc installed is able to compile
them fine. So, this change disables them until we can find a way to
compile them using clang on the buildbot workers.
The current generic implementation of the fmaf function has been moved
to the FPUtil directory. This allows one use the fma operation from
implementations of other math functions like the trignometric functions
without depending on/requiring the fma/fmaf/fmal function targets. If
this pattern ends being convenient, we will switch all generic math
implementations to this pattern.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D100811
This patch provides `TYPED_TEST` and `TYPED_TEST_F` (similar in functionnality to gtest).
This is needed to extensively test building blocks for memory functions.
Example for `TYPED_TEST_F`:
```
template <typename T> class LlvmLibcMyTestFixture : public testing::Test {};
using Types = testing::TypeList<char, int, long>;
TYPED_TEST_F(LlvmLibcMyTestFixture, Simple, Types) {
EXPECT_LE(sizeof(ParamType), 8UL);
}
```
Example for `TYPED_TEST`:
```
using Types = testing::TypeList<char, int, long>;
TYPED_TEST(LlvmLibcMyTest, Simple, Types) {
EXPECT_LE(sizeof(ParamType), 8UL);
}
```
`ParamType` is displayed as fully qualified canonical type which can be difficult to read, the user can provide a more readable name by using the `REGISTER_TYPE_NAME` macro.
Differential Revision: https://reviews.llvm.org/D100631
This helps us avoid the uncomfortable reinterpret-casts. Avoiding the
reinterpret casts prevents us from tripping the sanitizers as well.
Reviewed By: lntue
Differential Revision: https://reviews.llvm.org/D100360
b22f448c21 added a rule to install libllvmlibc.a to
${LIBC_INSTALL_PREFIX}/${LIBC_INSTALL_LIBRARY_DIR}, which will be /lib
by default, which is disruptive to builds that stay within a user's
/home holder:
$ ninja install
...
-- Installing: /lib/libllvmlibc.a
CMake Error at projects/libc/lib/cmake_install.cmake:54 (file):
file INSTALL cannot copy file
"/home/nathan/cbl/github/tc-build/build/llvm/stage1/projects/libc/lib/libllvmlibc.a"
to "/lib/libllvmlibc.a": Permission denied.
Call Stack (most recent call first):
projects/libc/cmake_install.cmake:51 (include)
projects/cmake_install.cmake:47 (include)
cmake_install.cmake:76 (include)
...
Change LIBC_INSTALL_PREFIX's default value to ${CMAKE_INSTALL_PREFIX} so
that 'ninja install' does not attempt to install anything outside of the
user's requested installation location.
Differential Revision: https://reviews.llvm.org/D99636
Reviewed By: sivachandra
Signed-off-by: Nathan Chancellor <nathan@kernel.org>
This is needed to prevent asan/msan instrumentation to redirect CopyBlock to `__asan_memcpy` (resp. `__msan_memcpy`).
These functions would then differ operation to `memcpy` which leads to reentrancy issues.
With this patch, `memcpy` is fully instrumented and covered by asan/msan.
If this turns out to be too expensive, instrumentation can be selectively or fully disabled through the use of the `__attribute__((no_sanitize(address, memory)))` annotation.
Differential Revision: https://reviews.llvm.org/D99598
gmtime and gmtime_r share the same common code. They call gmtime_internal
a static inline function. Thus added only validation tests for gmtime_r.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D99046
This change doesn't handle TIMEZONE, tm_isdst and leap seconds.
Moved shared code between mktime and gmtime into time_utils.cpp.
Reviewed By: sivachandra
Differential Revision: https://reviews.llvm.org/D98467
This option will build LLVM libc as a full libc by itself. In this mode,
it is not expected that it will be mixed with other libcs. The
non-full-build mode will be the default LLVM libc build mode. In a future
where LLVM libc is complete enough, the full libc build will be made the
default mode.
These functions used inline asm to read FPU state. This change adds
explicit unpoisoning in these functions as the sanitizers don't see the
read operations.
We want to be able to build and test the string functions in contexts
like that of Fuchsia where LLVM pieces like tablegen are not available.
Since header generation uses tablegen, we are removing the dependency on
headergen here.
Reviewed By: gchatelet
Differential Revision: https://reviews.llvm.org/D97363
Siva Chandra Reddy