[BLAS][generic] Fix compilation with AdaptiveCpp

The generic BLAS backend currently offers limited support for
AdaptiveCpp, where:
* complex data type is not supported
* USM API is not supported

Add the required protections to make the generic BLAS backend
compile and run correctly in the capacity it offers with AdaptiveCpp.
That is, make the buffer USM without complex data work fine. Throw
the unimplemented exception for the unsupported features.

This change relies on the update of the generic blas backend to
version 0.2.0 in:
uxlfoundation/generic-sycl-components#7

Author: rafbiels

src/blas/backends/generic/CMakeLists.txt

@@ -141,7 +141,7 @@ endif()
 # If find_package doesn't work, download onemath_sycl_blas from Github. This is
 # intended to make oneMath easier to use.
 message(STATUS "Looking for oneMATH blas kernels")
-find_package(ONEMATH_SYCL_BLAS QUIET)
+find_package(ONEMATH_SYCL_BLAS 0.2.0 QUIET)
 if (NOT ONEMATH_SYCL_BLAS_FOUND)
   message(STATUS "Looking for onemath_sycl_blas for generic backend - could not find onemath_sycl_blas with ONEMATH_SYCL_BLAS_DIR")
   include(FetchContent)
@@ -150,7 +150,6 @@ if (NOT ONEMATH_SYCL_BLAS_FOUND)
   endif()
   # Following variable TUNING_TARGET will be used in generic blas internal configuration
   set(TUNING_TARGET ${GENERIC_BLAS_TUNING_TARGET})
-  set(BLAS_ENABLE_COMPLEX ON)
   # Set the policy to forward variables to generic blas configure step
   set(CMAKE_POLICY_DEFAULT_CMP0077 NEW)
   set(FETCHCONTENT_BASE_DIR "${CMAKE_BINARY_DIR}/deps")
@@ -161,13 +160,21 @@ if (NOT ONEMATH_SYCL_BLAS_FOUND)
     SOURCE_SUBDIR onemath/sycl/blas
   )
   FetchContent_MakeAvailable(onemath_sycl_blas)
+  install(
+    TARGETS onemath_sycl_blas
+    EXPORT oneMathTargets
+  )
   message(STATUS "Looking for onemath_sycl_blas - downloaded")
 
 else()
   message(STATUS "Looking for oneMath blas kernels - found")
   add_library(onemath_sycl_blas ALIAS ONEMATH_SYCL_BLAS::onemath_sycl_blas)
 endif()
 
+# Read cmake options exported by the onemath_sycl_blas project into oneMath variables
+set(ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX ${BLAS_ENABLE_COMPLEX} CACHE INTERNAL  "Enable complex data support")
+set(ONEMATH_GENERIC_BLAS_ENABLE_USM ${BLAS_ENABLE_USM} CACHE INTERNAL  "Enable USM API support")
+
 set(SOURCES
   generic_level1_double.cpp generic_level1_float.cpp
   generic_level2_double.cpp generic_level2_float.cpp

src/blas/backends/generic/generic_common.hpp

@@ -21,6 +21,7 @@
 #define _GENERIC_BLAS_COMMON_HPP_
 
 #include "onemath_sycl_blas.hpp"
+#include "oneapi/math/detail/config.hpp"
 #include "oneapi/math/types.hpp"
 #include "oneapi/math/exceptions.hpp"
 
@@ -40,9 +41,11 @@ using handle_t = ::blas::SB_Handle;
 template <typename ElemT>
 using buffer_iterator_t = ::blas::BufferIterator<ElemT>;
 
+#ifdef ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX
 // sycl complex data type (experimental)
 template <typename ElemT>
 using sycl_complex_t = sycl::ext::oneapi::experimental::complex<ElemT>;
+#endif
 
 /** A trait for obtaining equivalent onemath_sycl_blas API types from oneMath API
  *  types.
@@ -68,8 +71,10 @@ DEF_GENERIC_BLAS_TYPE(oneapi::math::transpose, char)
 DEF_GENERIC_BLAS_TYPE(oneapi::math::uplo, char)
 DEF_GENERIC_BLAS_TYPE(oneapi::math::side, char)
 DEF_GENERIC_BLAS_TYPE(oneapi::math::diag, char)
+#ifdef ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX
 DEF_GENERIC_BLAS_TYPE(std::complex<float>, sycl_complex_t<float>)
 DEF_GENERIC_BLAS_TYPE(std::complex<double>, sycl_complex_t<double>)
+#endif
 // Passthrough of onemath_sycl_blas arg types for more complex wrapping.
 DEF_GENERIC_BLAS_TYPE(::blas::gemm_batch_type_t, ::blas::gemm_batch_type_t)
 
@@ -85,6 +90,7 @@ struct generic_type<ElemT*> {
     using type = ElemT*;
 };
 
+#ifdef ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX
 // USM Complex
 template <typename ElemT>
 struct generic_type<std::complex<ElemT>*> {
@@ -95,6 +101,7 @@ template <typename ElemT>
 struct generic_type<const std::complex<ElemT>*> {
     using type = const sycl_complex_t<ElemT>*;
 };
+#endif
 
 template <>
 struct generic_type<std::vector<sycl::event>> {
@@ -210,6 +217,10 @@ struct throw_if_unsupported_by_device {
         throw unimplemented("blas", "onemath_sycl_blas function");                              \
     }
 
+#ifndef ONEMATH_GENERIC_BLAS_ENABLE_USM
+#define CALL_GENERIC_BLAS_USM_FN(genericFunc, ...) \
+    throw unimplemented("blas", "onemath_sycl_blas USM API", "- unsupported compiler");
+#else
 #define CALL_GENERIC_BLAS_USM_FN(genericFunc, ...)                                \
     if constexpr (is_column_major()) {                                            \
         detail::throw_if_unsupported_by_device<double, sycl::aspect::fp64>{}(     \
@@ -230,6 +241,7 @@ struct throw_if_unsupported_by_device {
     else {                                                                        \
         throw unimplemented("blas", "onemath_sycl_blas function");                \
     }
+#endif
 
 } // namespace generic
 } // namespace blas

src/blas/backends/generic/generic_level3.cxx

@@ -32,6 +32,10 @@ void gemm(sycl::queue& queue, oneapi::math::transpose transa, oneapi::math::tran
           sycl::buffer<std::complex<real_t>, 1>& a, std::int64_t lda,
           sycl::buffer<std::complex<real_t>, 1>& b, std::int64_t ldb, std::complex<real_t> beta,
           sycl::buffer<std::complex<real_t>, 1>& c, std::int64_t ldc) {
+#ifndef ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX
+    throw unimplemented("blas", "onemath_sycl_blas gemm with complex data type",
+                        "- unsupported compiler");
+#else
     using sycl_complex_real_t = sycl::ext::oneapi::experimental::complex<real_t>;
     if (transa == oneapi::math::transpose::conjtrans ||
         transb == oneapi::math::transpose::conjtrans) {
@@ -62,6 +66,7 @@ void gemm(sycl::queue& queue, oneapi::math::transpose transa, oneapi::math::tran
     sycl::accessor<std::complex<real_t>, 1, sycl::access::mode::write> out_acc(c);
     sycl::accessor<sycl_complex_real_t, 1, sycl::access::mode::read> out_pb_acc(c_pb);
     queue.copy(out_pb_acc, out_acc);
+#endif
 }
 
 void symm(sycl::queue& queue, oneapi::math::side left_right, oneapi::math::uplo upper_lower,

src/config.hpp.in

@@ -34,6 +34,8 @@
 #cmakedefine ONEMATH_ENABLE_GENERIC_BLAS_BACKEND_INTEL_CPU
 #cmakedefine ONEMATH_ENABLE_GENERIC_BLAS_BACKEND_INTEL_GPU
 #cmakedefine ONEMATH_ENABLE_GENERIC_BLAS_BACKEND_NVIDIA_GPU
+#cmakedefine ONEMATH_GENERIC_BLAS_ENABLE_COMPLEX
+#cmakedefine ONEMATH_GENERIC_BLAS_ENABLE_USM
 #cmakedefine ONEMATH_ENABLE_PORTFFT_BACKEND
 #cmakedefine ONEMATH_ENABLE_ROCBLAS_BACKEND
 #cmakedefine ONEMATH_ENABLE_ROCFFT_BACKEND