Fix precompiled kernels on POWER9 and make their use conditional on (old) gcc version

Fix SEGV in cdot_power9

used in KERNEL.POWER9

We were corrupting r2 because the local entry wasn't being
setup correctly.

The ZARCH implementations of ?sum contain a cut & paste-error: An inline
assembly argument is named "sum", but the assembly references "asum"
instead.  The mismatch causes a build error.  This is fixed.

revised fix windows compatible for #2313

Signed-off-by: Wang, Long <long1.wang@intel.com>

Further Power8 big-endian corrections

Signed-off-by: Wang, Long <long1.wang@intel.com>

For large matrix, e.g. M=N=K, and M>1290, int mnk=M*N*K will overflow.
This will lead to wrong branching to single-threading. The performance
is downgraded significantly.

Signed-off-by: Wang, Long <long1.wang@intel.com>

Fix PPC970 big-endian support

The altivec versions of SGEMM and CGEMM fail most test in LAPACK-TESTING when compiled for big endian, STRSM/CTRSM even cause segfaults. The rot kernels either fail the corresponding utest or lead to failures in LAPACK-TESTING.

AVX512 CGEMM & ZGEMM kernels

96-99% 1-thread performance of MKL2018

Optimize SGEMM on SKYLAKEX CPUs

Disable IDAMIN/MAX and IZAMIN/MAX optimizations on big-endian POWER8

90% MKL 1-thread performance.

Rewrite ARMV8 code to allow cross-compilation for IOS

... which does not perform the automatic numbering on instantiation that the _@ suffix signifies

fixed bug power9 strmm . BLAS-TESTER passes

* Add gcc7-generated assembly files for POWER8/9 isa/ica-min/max and POWER9 caxpy

To work around internal compiler errors encountered when compiling the original C source with gcc 4 and 5, and wrong code generated by gcc 8.3.0

* Use gcc-generated assembly instead of original C sources

to work around internal compiler errors encountered with gcc 4.8/5.4 and wrong code generation by gcc 8.3

* Use gcc-generated assembly instead of the original C source

to work around internal compiler errors encountered with gcc 4.8 and 5.4, and wrong code generation by gcc 8.3

* Add gcc7-generated assembler version of caxpy for power8

to work around wrong code generated by gcc 8.3

* Handle CONJ define for caxpyc

* Handle CONJ define for caxpyc

* Add gcc7-generated assembly cdot for POWER9

* Use prebuilt assembly for POWER9 cdot

created with gcc 7.3.1 to work around ICE in older gcc versions

* Exclude POWER9 from DYNAMIC_ARCH when gcc versions is lower than 6

* Update Makefile.system

* Use PROLOGUE macro to ensure correct function name for DYNAMIC_ARCH

* Disable POWER9 with old gcc versions