Add Missing Features chapter to README (#534)

Author: s-Nick

README.md

@@ -523,3 +523,4 @@ report bugs.
 
 - [How to add a new operation](doc/AddingBlas3Op.md)
 - [Autotuner Developer Guide](doc/Autotuner.md)
+- [Missing Features](doc/MissingFeatures.md)

doc/MissingFeatures.md

@@ -0,0 +1,43 @@
+## Missing Features
+
+The following is a list of features missing in portBLAS for supporting entirely the [oneAPI oneMKL BLAS interface](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/blas).
+The order does not reflect any kind of priority.
+
+For questions regarding input types or operators support, please refer to the link above.
+
+- Add row-major support to level-1 operators.
+- Add row-major support to level-2 operators.
+- Add row-major support to level-3 operators.
+- Add complex support to level-1 operators that required it: asum, axpy, copy, nrm2, rot, rotg, scal, swap, iamax, iamin.
+- Implement [dotc](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/dotc.html#onemkl-blas-dotc) operator.
+- Implement [dotu](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/dotu.html#onemkl-blas-dotu) operator.
+- Add complex support to level-2 operators that required it: gbmv, gemv, symv, syr, syr2, tbmv, tbsv, tpmv, tpsv, trmv, trsv.
+- Implement [gerc](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/gerc.html#onemkl-blas-gerc) level-2 operator.
+- Implement [geru](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/geru.html#onemkl-blas-geru) level-2 operator.
+- Implement [hbmv](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hbmv.html#onemkl-blas-hbmv) level-2 operator.
+- Implement [hemv](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hemv.html#onemkl-blas-hemv) level-2 operator.
+- Implement [her](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/her.html#onemkl-blas-her) level-2 operator.
+- Implement [her2](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/her2.html#onemkl-blas-her2) level-2 operator.
+- Implement [hpmv](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hpmv.html#onemkl-blas-hpmv) level-2 operator.
+- Implement [hpr](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hpr.html#onemkl-blas-hpr) level-2 operator.
+- Implement [hpr2](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hpr2.html#onemkl-blas-hpr2) level-2 operator.
+- Add complex support to level-3 operators that required it: trsm.
+- Implement [hemm](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/hemm#onemkl-blas-hemm) level-3 operator.
+- Implement [herk](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/herk#onemkl-blas-herk) level-3 operator.
+- Implement [her2k](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/her2k#onemkl-blas-her2k) level-3 operator.
+- Implement [syrk](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/syrk.html#onemkl-blas-syrk) level-3 operator.
+- Implement [syr2k](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/syr2k.html#onemkl-blas-syr2k) level-3 operator.
+- Implement [trmm](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/trmm.html#onemkl-blas-trmm) level-3 operator.
+- Add complex support to extenstion operators that required it: axpy_batch, omatcopy, omatcopy_batch, omatcopy2, omatadd, omatadd_batch.
+- Implement [trsm_batch](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/trsm_batch.html#onemkl-blas-trsm-batch) extension operator.
+- Implement [gemmt](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/gemmt.html#onemkl-blas-gemmt) extension operator.
+- Implement [imatcopy](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/imatcopy#onemkl-blas-imatcopy) extension operator.
+- Implement [imatcopy_batch](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/imatcopy_batch#onemkl-blas-imatcopy-batch) extension operator.
+- Implement [gemm_bias](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/gemm_bias.html#onemkl-blas-gemm-bias) extension operator.
+- Add different input types support to [gemm](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/gemm#onemkl-blas-gemm)/[gemm_batch](https://oneapi-spec.uxlfoundation.org/specifications/oneapi/latest/elements/onemkl/source/domains/blas/gemm_batch#onemkl-blas-gemm-batch). 
+- Add half support to level-1 operators that required it: dot, nrm2, rot.
+- Add bfloat16 support to level-1 operators that required it: axpy, copy, dot, nrm2, rot, scal.
+- Add interface support for scalar value on device for level-1 operators: axpy, rot, scal.
+- Add interface support for scalar value on device for level-2 operators: gbmv, gemv, ger, sbmv, spmv, spr, spr2, symv, syr, syr2.
+- Add interface support for scalar value on device for level-3 operators: gemm, symm, trmm.
+- Add interface support for scalar value on device for extension operators: axpy_batch, omatcopy, omatcopy2, omatadd, omatcopy_batch, omatadd_batch.