COMPMID-1271: New system for GEMM heuristics

This patch implements a system for separating the "validity" from
"preferred" aspect of the current heuristics in gemm_*.cpp.

Now, each gemm_*.cpp defines a list of candidate implementations,
each of which supplies an is_valid() function (to check for
validity), an is_preferred() function (the "heuristic" part), and an
instantiate() function which actually produces the GemmCommon object
pointer.

The actual gemm() function is now templated and uses this list to
select an implementation.  This patch also implements a mechanism to
identify the preferred implementation, and override it via the
GemmConfig structure.

Change-Id: Id49ab7af8bf2e3e9fd951a9698883ade234d40e1
Reviewed-on: https://eu-gerrit-1.euhpc.arm.com/139120
Reviewed-by: Anthony Barbier <anthony.barbier@arm.com>
Tested-by: Jenkins <bsgcomp@arm.com>

1 files changed, 11 insertions, 3 deletions

diff --git a/src/core/NEON/kernels/arm_gemm/kernels/a64_sgemm_native_16x4.hpp b/src/core/NEON/kernels/arm_gemm/kernels/a64_sgemm_native_16x4.hpp
index 11a589d75c..1a3596511b 100644
--- a/src/core/NEON/kernels/arm_gemm/kernels/a64_sgemm_native_16x4.hpp
+++ b/src/core/NEON/kernels/arm_gemm/kernels/a64_sgemm_native_16x4.hpp
@@ -46,9 +46,17 @@ public:
     typedef void (*kern_type)(const float *, int, const float *, int, float *, int, float, int, int, int);
 
     /* Kernel blocking parameters */
-    static const int out_width = 16;
-    static const int out_height = 4;
-    static const int k_unroll = 1;
+    static int out_width() {
+        return 16;
+    }
+
+    static int out_height() {
+        return 4;
+    }
+
+    static int k_unroll() {
+        return 1;
+    }
 
     // Default to the generic kernel
     kern_type kernel=a64_sgemm_native_16x4;