[cpu][fix] Fix onednn_mm crash on consecutive matmuls with same M,K,N and different dtype

Makes weight dtype part of the cache key for `ClassMatmulCacheKey` to avoid having 2 onednn_mm(s)
with same src/weight dimensions and different dtypes mapped to the same dnnl::matmul primitive

Fixes: #27465

Signed-off-by: Fadi Arafeh <fadi.arafeh@arm.com>

Author: fadara01

csrc/cpu/dnnl_helper.cpp

@@ -187,7 +187,8 @@ template <>
 struct hash<MatMulPrimitiveHandler::ClassMatmulCacheKey> {
   size_t operator()(
       const MatMulPrimitiveHandler::ClassMatmulCacheKey& val) const {
-    return hash<dnnl_dim_t>()(val.b_n_size) ^ hash<dnnl_dim_t>()(val.b_k_size);
+    return hash<dnnl_dim_t>()(val.b_n_size) ^ hash<dnnl_dim_t>()(val.b_k_size) ^
+           hash<int>()(static_cast<int>(val.b_type));
   }
 };
 
@@ -216,7 +217,8 @@ bool operator==(const W8A8MatMulPrimitiveHandler::MSizeCacheKey& l,
 
 bool operator==(const MatMulPrimitiveHandler::ClassMatmulCacheKey& l,
                 const MatMulPrimitiveHandler::ClassMatmulCacheKey& r) {
-  return l.b_n_size == r.b_n_size && l.b_k_size == r.b_k_size;
+  return l.b_n_size == r.b_n_size && l.b_k_size == r.b_k_size &&
+         l.b_type == r.b_type;
 }
 
 bool operator==(const MatMulPrimitiveHandler::MSizeCacheKey& l,
@@ -493,8 +495,9 @@ void MatMulPrimitiveHandler::execute(ExecArgs& args) {
 dnnl::matmul MatMulPrimitiveHandler::get_matmul_cache(
     const MSizeCacheKey& key) {
   if (m_size_cache_.get() == nullptr) {
-    ClassMatmulCacheKey key = {.b_n_size = b_n_size_, .b_k_size = b_k_size_};
-    m_size_cache_ = get_matul_class_primitive_cache(key, primitive_cache_size_);
+    ClassMatmulCacheKey class_key = {
+        .b_n_size = b_n_size_, .b_k_size = b_k_size_, .b_type = b_type_};
+    m_size_cache_ = get_matul_class_primitive_cache(class_key, primitive_cache_size_);
   }
   return m_size_cache_->get_or_create(key, [&]() {
     dnnl::matmul::primitive_desc desc = this->create_primitive_desc(key, false);

csrc/cpu/dnnl_helper.h

@@ -199,6 +199,7 @@ class MatMulPrimitiveHandler : public DNNLMatMulPrimitiveHandler {
   struct ClassMatmulCacheKey {
     dnnl_dim_t b_n_size;
     dnnl_dim_t b_k_size;
+    dnnl::memory::data_type b_type;
 
     friend bool operator==(const ClassMatmulCacheKey& l,
                            const ClassMatmulCacheKey& r);