This patch fixes compilation errors due to recent renaming from SH to SB
with BUILD_BFLOAT16.

Avoid out of bounds access on invalid memory free

Lazyly reinit threads after a fork in OMP mode

This initializes the per-thread memory buffers which get
cleared/released on a fork via pthread_at_fork. Not doing so leads to
each thread calling blas_memory_alloc on almost every execution which
slows down the code significantly as the threads race for the memory
allocation using locks to serialize that.

Adding performance patch for trmm, just like trsm (#2836)

Add bfloat16 based dot and conversion with single/double

Enable building DYNAMIC_ARCH support with older versions of glibc that
do not know about the hwcap flag HWCAP_S390_VXE yet.

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

... instead of duplicating the (old) mechanism from the Makefile that
aimed to derive supported architecture generations from the gcc
version.

To enable builds with DYNAMIC_ARCH with older compiler releases, the
Makefile and drivers/other/dynamic_arch.c need a common view of the
architecture support built into the library.

We follow the notation from x86 when used with DYNAMIC_LIST, where
defines DYN_<ARCH NAME> denote support for a given generation to be
built in. Since there are far fewer architecture generations in OpenBLAS
for s390x, that does not bloat command lines too much.

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

1. Added bfloat16 based dot as new API: shdot
2. Implemented generic kernel and cooperlake-specific (AVX512-BF16) kernel for shdot
3. Added 4 conversion APIs for bfloat16 data type <=> single/double: shstobf16 shdtobf16 sbf16tos dbf16tod
     shstobf16 -- convert single float array to bfloat16 array
     shdtobf16 -- convert double float array to bfloat16 array
     sbf16tos  -- convert bfloat16 array to single float array
     dbf16tod  -- convert bfloat16 array to double float array
4. Implemented generic kernels for all 4 conversion APIs, and cooperlake-specific kernel for shstobf16 and shdtobf16
5. Update level1 thread facilitate functions and macros to support multi-threading for these new APIs
6. Fix Cooperlake platform detection/specify issue when under dynamic-arch building
7. Change the typedef of bfloat16 from unsigned short to more strict uint16_t

Signed-off-by: Chen, Guobing <guobing.chen@intel.com>

In current code, no matter what number of threads specified, all
available CPU count is used when invoking OMP, which leads to very bad
performance if the workload is small while all available CPUs are big.
Lots of time are wasted on inter-thread sync. Fix this issue by really
using the number specified by the variable 'num' from calling API.

Signed-off-by: Chen, Guobing <guobing.chen@intel.com>

Enable new build target platform -- COOPERLAKE. This target platform
supports all the SKYLAKEX supported ISAs + avx512bf16. So all the
SKYLAKEX specific kernels/drivers and related code are now extended
to be also active on COOPERLAKE. Besides, new BF16 related kernels
are active under this target.

Add AMD Renoir/Matisse cpu autodetection and preliminary support for Zen3

also support AMD family 22 Jaguar/Puma as Bobcat

As the MMA patches for POWER10 are backported to gcc10.2, changing
the minimum gcc version needed to build OpenBLAS for POWER10.

As compiler enabled mcpu option as power10, changing it from future.

powerpc: Add support for future processor

This is the initial patch to support build infrastructure
for POWER10 architecture.

Extend and simplify the run-time detection for dynamic architecture support for z
to check HW_CAP and only use SIMD features if advertised by the OS.
While at it, also honor the env variable LD_HWCAP_MASK and do not use
the CPU features masked there.

Note that we can only use the SIMD features on z13 or newer (i.e.,
Vector Facility or Vector-Enhancements Facilities) when the operating
system supports properly context-switching the vector registers. The OS
advertises that support as a bit in the HW_CAP value in the auxiliary
vector. While all recent Linux kernels have that support, we should
maintain compatibility with older versions that may still be in use.

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

When building OpenBLAS with DYNAMIC_ARCH=1 on s390x (aka zarch), make
sure to include support for systems without the facilities introduced
with z13 (i.e., zarch_generic). Adjust runtime detection to fallback to
that generic code when running on a unknown platform other than Z13
through Z15.

When detecting a Z13 or newer system, add a check for gcc support for
the architecture-specific features before selecting the respective
kernel. Fallback to Z13 or generic code, in case.

Signed-off-by: Marius Hillenbrand <mhillen@linux.ibm.com>

* make building the bfloat16 BLAS functions conditional on BUILD_HALF

* pass the BUILD_HALF option to gensymbol

* Pass BUILD_HALF as a compiler define for dynamic_arch builds

This patch adds support for bfloat16 data type matrix multiplication kernel.
For architectures that don't support bfloat16, it is defined as unsigned short
(2 bytes).  Default unroll sizes can be changed as per architecture as done for
SGEMM and for now 8 and 4 are used for M and N.  Size of ncopy/tcopy can be
changed as per architecture requirement and for now, size 2 is used.

Added shgemm in kernel/power/KERNEL.POWER9 and tested in powerpc64le and
powerpc64.  For reference, added a small test compare_sgemm_shgemm.c to compare
sgemm and shgemm output.

This patch does not cover OpenBLAS test, benchmark and lapack tests for shgemm.
Complex type implementation can be discussed and added once this is approved.