[release 3.2] Changelog file additions.

This patch adds preliminary support for MinGW.
Only building static libm is possible at this time.
This patch also adds build-only testing on Appveyor.

This patch changes the version number from 3.1 to 3.2

This terminates the migration work mentioned in https://github.com/shibatch/sleef/issues/30

This commit addresses the problem raised in https://github.com/shibatch/sleef/issues/172

This patch replaces the old benchmarking tool with a new tool with gnuplot.

With this new tool, the graph showing execution time can be automatically drawn.
It is now easy to see the difference between different library versions or compilers.
This tool is used to draw the graphs on sleef.org web site.

This patch implements the tool described in https://github.com/shibatch/sleef/issues/9.

A makefile is used In this patch. It is used to compile the necessary tools.
This makefile is used as a script for measurement. It is handy since ProcData.java has to be also compiled.

This patch fixes a bug in CMakelists.txt which was preventing build static libs with MSVC (see #172 ). This patch also adds directive for building static libs on appveryor.

[cmake] Link librt explicitly.

This is required to prevent failures in our downstream builders
when performing the 2-step cross compilation process.

Patch from Sander de Smalen @ Arm.

With this patch, sqrt functions utilizes an instruction for computing sqrt if available.
This patch also adds -fno-math-errno and -fno-trapping-math compiler options when compiled by gcc or clang.

This patch removes source codes for the old benchmarking tools.

With this patch, the following changes are made to the html docs.

* PR #153 is reflected.
* Explanation for the benchmarking tool in PR #98 is added.
* A small amount of explanation on the GNUABI version of library is added.
* Benchmark results are updated to comparison between sleef 3.2 and SVML comes with icc 18.0.1.

This patch adds aliases without a vector extension name to the existing functions.
This is implementation of issue #137.
In addition to aarch64 and aarch32, this patch adds aliases to AVX512F functions.

* This patch turn off building GNUABI library on aarch32

A cmake function for compatibility tests is implemented.

This set of tests make sure tht the symbols we generate in `libsleefgnuabi.so` are compatible with the naming conventions of `libmvec` in `glibc`.

Note: we ship log2[f] in the library but we don't provide a finite symbol for it, although GNU libm on x86 expects it. This will be fixed in a separate commit/PR.This issue is tracked in https://github.com/shibatch/sleef/issues/164.

With this patch, the following functionalities are added.

* Cross compilation without qemu is made possible. This is basically implementation in #157.
* aarch64 and armhf builds and testing on travis are implemented.
* Configuration file for travis-ci is now cleaned up and they are separated to shell scripts. This provides greater control over what to do for each configuration.
* Tester now supports flush-to-zero mode regardless of the target architecture.

For aarch64 and armhf builds and testing on travis, docker has to be used. This is because only gcc-4.8 can be used without docker, and I couldn't find newer cross compilers.
Usage of sde is now turned off for linux-clang setting, since it takes long time. It is enabled only for x86_64-gcc setting only.

Before cross-compilation, native build has to be executed.

If qemu with binfmt_misc is available, native build can be skipped.
In this case, FALSE has to be set to CMAKE_CROSSCOMPILING variable in the toolchain file.
An emulator can be specified for testing.

cmake -DCMAKE_TOOLCHAIN_FILE=../../toolchain-aarch64-binfmt.cmake -DEMULATOR=qemu-aarch64-static ..

This implements the change suggested by Naoki in [1] to fix the
failure in [2].

[1] https://github.com/shibatch/sleef/pull/157
[2] https://travis-ci.org/shibatch/sleef/builds/334713491

* [cmake] Cross compiling tweaks.

Some of our downstream CI pipelines rely on cross-compiling SLEEF on
X86 and targeting AArch64.

This patch consists of the changes I needed to implement in the cmake
configuration to make it work on those CI environment.

No functional change is intended.

[libm] Remove dependency on libm

* Updates the HTML documents under doc/html directory

* Updated benchmark results

Remove debian directory

[GNUABI] Adding masked versions of vector functions.

Merge branch 'Add_masked_functions2' of https://github.com/shibatch/sleef into Add_masked_functions2

vmaxnum_v*_v*_v* and vminnum_v*_v*_v* are helper functions for utilizing instructions for choosing larger and smaller elements from two given vectors, and they are introduced in the following PR.

https://github.com/shibatch/sleef/pull/109

It is said that vmaxnmq and vminnmq on aarch64 are IEEE754-conformant, but I recently found that handling of signalling NaN by these instructions is not conforming to the specification of fmin and fmax functions in the ANSI C standard.

This patch fixes that problem. It also adds regression test for checking signaling nan handling in fmin and fmax.

Fix the weak alias check for Cygwin to prevent failures on appveyor.

With this patch, parallel builds will become stable on linux and macOS.
On MSVC, parallel builds may fail due to a build system problem.

* This patch fixes the problem in which the dispatchers do not choose the best availble extension.
With this patch, the selected extension will be displayed upon execution of iutsimd.

* Naming convention of the dispatcher macros are changed to make them easier to understand. Explanation of the macros are also added.

With this patch, testing on appveyor is enabled.
The tester is compiled on Cygwin.

This patch makes the testers to run on Intel SDE.
The SDE is only used when the corresponding extension is not available on the computer.

In this patch, the SDE package is downloaded from the URL retained in SDE_URL.
SDE_URL is a Travis secure environment variable. Since redistribution of SDE is not allowed, we need to hide where we are downloading the SDE package from.

Travis terminates running programs if it does not receive anything from stdout of the program for 10 minutes. So --verbose option is used in testing.

https://github.com/shibatch/sleef/issues/85

This patch allows optional builds of static libs.
On Windows, SLEEF_STATIC_LIBS macro has to be defined before including sleef.h and sleefdft.h in order to link the user code with the static libs.
The GNUABI version of libraries are built as shared libraries regardless of the option.