ggml-zendnn : add ZenDNN backend for AMD CPUs (llama/17690)

* ggml-zennn: add ZenDNN backend support

* ggml-zendnn : address ZenDNN backend review fixes and suggestions

* docs : apply blockquote syntax to ZenDNN docs

---------

Co-authored-by: Manoj Kumar <mkumar@zettabolt.com>

ggml/CMakeLists.txt

@@ -253,6 +253,9 @@ option(GGML_HEXAGON                         "ggml: enable Hexagon backend"
 # toolchain for vulkan-shaders-gen
 set   (GGML_VULKAN_SHADERS_GEN_TOOLCHAIN "" CACHE FILEPATH "ggml: toolchain file for vulkan-shaders-gen")
 
+option(GGML_ZENDNN                          "ggml: use ZenDNN"                                OFF)
+option(ZENDNN_ROOT                          "ggml: path to ZenDNN installation"               "")
+
 # extra artifacts
 option(GGML_BUILD_TESTS    "ggml: build tests"    ${GGML_STANDALONE})
 option(GGML_BUILD_EXAMPLES "ggml: build examples" ${GGML_STANDALONE})
@@ -314,6 +317,7 @@ set(GGML_PUBLIC_HEADERS
     include/ggml-sycl.h
     include/ggml-vulkan.h
     include/ggml-webgpu.h
+    include/ggml-zendnn.h
     include/gguf.h)
 
 set_target_properties(ggml PROPERTIES PUBLIC_HEADER "${GGML_PUBLIC_HEADERS}")

ggml/include/ggml-zendnn.h

@@ -0,0 +1,22 @@
+#pragma once
+
+#include "ggml-backend.h"
+#include "ggml.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+// backend API
+GGML_BACKEND_API ggml_backend_t ggml_backend_zendnn_init(void);
+
+GGML_BACKEND_API bool ggml_backend_is_zendnn(ggml_backend_t backend);
+
+// number of threads used for zendnn operations
+GGML_BACKEND_API void ggml_backend_zendnn_set_n_threads(ggml_backend_t backend_zendnn, int n_threads);
+
+GGML_BACKEND_API ggml_backend_reg_t ggml_backend_zendnn_reg(void);
+
+#ifdef __cplusplus
+}
+#endif

ggml/src/CMakeLists.txt

@@ -440,6 +440,7 @@ ggml_add_backend(WebGPU)
 ggml_add_backend(zDNN)
 ggml_add_backend(OpenCL)
 ggml_add_backend(Hexagon)
+ggml_add_backend(ZenDNN)
 
 foreach (target ggml-base ggml)
     target_include_directories(${target} PUBLIC    $<BUILD_INTERFACE:${CMAKE_CURRENT_SOURCE_DIR}/../include> $<INSTALL_INTERFACE:include>)

ggml/src/ggml-backend-reg.cpp

@@ -73,6 +73,10 @@
 #include "ggml-cann.h"
 #endif
 
+#ifdef GGML_USE_ZENDNN
+#include "ggml-zendnn.h"
+#endif
+
 // disable C++17 deprecation warning for std::codecvt_utf8
 #if defined(__clang__)
 #    pragma clang diagnostic push
@@ -203,6 +207,9 @@ struct ggml_backend_registry {
 #ifdef GGML_USE_OPENCL
         register_backend(ggml_backend_opencl_reg());
 #endif
+#ifdef GGML_USE_ZENDNN
+        register_backend(ggml_backend_zendnn_reg());
+#endif
 #ifdef GGML_USE_HEXAGON
         register_backend(ggml_backend_hexagon_reg());
 #endif
@@ -605,6 +612,7 @@ void ggml_backend_load_all_from_path(const char * dir_path) {
 #endif
 
     ggml_backend_load_best("blas", silent, dir_path);
+    ggml_backend_load_best("zendnn", silent, dir_path);
     ggml_backend_load_best("cann", silent, dir_path);
     ggml_backend_load_best("cuda", silent, dir_path);
     ggml_backend_load_best("hip", silent, dir_path);

ggml/src/ggml-zendnn/CMakeLists.txt

@@ -0,0 +1,92 @@
+ggml_add_backend_library(ggml-zendnn
+                         ggml-zendnn.cpp)
+
+# Get ZenDNN path
+if (NOT DEFINED ZENDNN_ROOT OR ZENDNN_ROOT STREQUAL "")
+    set(ZENDNN_ROOT "$ENV{ZENDNN_ROOT}")
+endif()
+
+# Check if path is still empty or OFF
+if (NOT ZENDNN_ROOT OR ZENDNN_ROOT STREQUAL "" OR ZENDNN_ROOT STREQUAL "OFF")
+    message(STATUS "ZENDNN_ROOT not set. Automatically downloading and building ZenDNN...")
+    message(STATUS "This will take several minutes on first build...")
+
+    include(ExternalProject)
+
+    set(ZENDNN_PREFIX      ${CMAKE_BINARY_DIR}/_deps/zendnn-prefix)
+    set(ZENDNN_SOURCE_DIR  ${ZENDNN_PREFIX}/src/zendnn)
+    set(ZENDNN_BUILD_DIR   ${ZENDNN_PREFIX}/build)
+    set(ZENDNN_INSTALL_DIR ${ZENDNN_BUILD_DIR}/install)
+
+    ExternalProject_Add(
+        zendnn
+        GIT_REPOSITORY https://github.com/amd/ZenDNN.git
+        GIT_TAG zendnnl
+        PREFIX      ${ZENDNN_PREFIX}
+        SOURCE_DIR  ${ZENDNN_SOURCE_DIR}
+        BINARY_DIR  ${ZENDNN_BUILD_DIR}
+        CMAKE_ARGS
+            -DCMAKE_BUILD_TYPE=Release
+            -DCMAKE_INSTALL_PREFIX=${ZENDNN_INSTALL_DIR}
+            -DZENDNNL_BUILD_EXAMPLES=OFF
+            -DZENDNNL_BUILD_DOXYGEN=OFF
+            -DZENDNNL_BUILD_GTEST=OFF
+            -DZENDNNL_BUILD_BENCHDNN=OFF
+            # Enable ALL matmul algorithm backends
+            -DZENDNNL_DEPENDS_AOCLDLP=ON
+            -DZENDNNL_DEPENDS_ONEDNN=ON
+            -DZENDNNL_DEPENDS_LIBXSMM=ON
+        BUILD_COMMAND   ${CMAKE_COMMAND} --build ${ZENDNN_BUILD_DIR} --target zendnnl
+        INSTALL_COMMAND ${CMAKE_COMMAND} --build ${ZENDNN_BUILD_DIR} --target install
+        BUILD_ALWAYS OFF
+        LOG_DOWNLOAD ON
+        LOG_CONFIGURE ON
+        LOG_BUILD ON
+        LOG_INSTALL ON
+    )
+
+    # Add dependency so ZenDNN builds before our library
+    add_dependencies(ggml-zendnn zendnn)
+
+    # Set ZENDNN_ROOT to the installation directory
+    set(ZENDNN_ROOT ${ZENDNN_INSTALL_DIR})
+
+    message(STATUS "ZenDNN will be built to: ${ZENDNN_ROOT}")
+else()
+    message(STATUS "Using custom ZenDNN installation at: ${ZENDNN_ROOT}")
+endif()
+
+# ZenDNN headers + libs
+target_include_directories(ggml-zendnn PRIVATE
+    ${ZENDNN_ROOT}/zendnnl/include
+    ${ZENDNN_ROOT}/deps/aocldlp/include
+    ${ZENDNN_ROOT}/deps/aoclutils/include
+    ${ZENDNN_ROOT}/deps/json/include
+    ${ZENDNN_ROOT}/deps/libxsmm/include
+    ${ZENDNN_ROOT}/deps/onednn/include
+)
+
+target_link_directories(ggml-zendnn PRIVATE
+    ${ZENDNN_ROOT}/zendnnl/lib
+    ${ZENDNN_ROOT}/deps/aocldlp/lib
+    ${ZENDNN_ROOT}/deps/aoclutils/lib
+    ${ZENDNN_ROOT}/deps/libxsmm/lib
+    ${ZENDNN_ROOT}/deps/onednn/lib
+)
+
+target_link_libraries(ggml-zendnn PRIVATE
+    zendnnl_archive    # ZenDNN main
+    aocl-dlp           # AOCL libraries
+    aoclutils
+    au_cpuid
+    dnnl               # OneDNN
+    xsmm               # libxsmm small matrix math
+    xsmmext
+    xsmmnoblas
+    m
+    pthread
+)
+
+if (GGML_OPENMP)
+    target_link_libraries(ggml-zendnn PRIVATE OpenMP::OpenMP_CXX)
+endif()

ggml/src/ggml-zendnn/ggml-zendnn.cpp

@@ -0,0 +1,466 @@
+#include "ggml-zendnn.h"
+
+#include "ggml-backend-impl.h"
+#include "ggml-impl.h"
+#include "ggml-cpu.h"
+#include "zendnnl.hpp"
+
+#include <cstring>
+
+
+struct ggml_backend_zendnn_context {
+    int n_threads = GGML_DEFAULT_N_THREADS;
+    std::unique_ptr<char[]> work_data;
+    size_t work_size = 0;
+};
+
+template<typename T>
+zendnnl::common::data_type_t ggml_to_zendnn_type() {
+    if constexpr (std::is_same_v<T, float>) {
+        return zendnnl::common::data_type_t::f32;
+    } else if constexpr (std::is_same_v<T, ggml_bf16_t>) {
+        return zendnnl::common::data_type_t::bf16;
+    } else {
+        return zendnnl::common::data_type_t::none;
+    }
+}
+
+/**
+ * ZenDNN matmul: computes C = B * A.
+ *
+ * - A: weights, shape (k, m), column-major (each column is a weight vector for one output).
+ * - B: input, shape (n, k), row-major (each row is an input sample).
+ * - C: output, shape (n, m), row-major.
+ *
+ * Dimensions:
+ *   m = output features (columns of C, columns of A)
+ *   n = batch size      (rows of C, rows of B)
+ *   k = inner dimension (columns of B, rows of A)
+ */
+template <typename TA, typename TB, typename TC>
+static bool ggml_zendnn_matmul(ggml_backend_zendnn_context * ctx, int64_t m, int64_t n, int64_t k,
+                               const TA * A, int64_t lda, const TB * B, int64_t ldb, TC * C,
+                               int64_t ldc) {
+
+    zendnnl::lowoha::lowoha_params params;
+    params.dtypes.src = ggml_to_zendnn_type<TB>();
+    params.dtypes.wei = ggml_to_zendnn_type<TA>();
+    params.dtypes.dst = ggml_to_zendnn_type<TC>();
+    params.num_threads = ctx->n_threads;
+
+    zendnnl::lowoha::status_t status = zendnnl::lowoha::matmul_direct(
+        'r', false, true,   // row-major, don't transpose B, transpose A (because it's column-major)
+        n,                  // M: rows of B and C
+        m,                  // N: cols of A^T and C
+        k,                  // K: cols of B, rows of A
+        1.0f,               // alpha
+        B, ldb,             // src: B[n,k]
+        A, lda,             // weight: A[k,m] column-major (transposed)
+        nullptr,            // bias
+        0.0f,               // beta
+        C, ldc,             // output C[n,m]
+        true,               // is_weights_const
+        {},                 // batch_params
+        params              // params
+    );
+
+    if (status != zendnnl::lowoha::status_t::success) {
+        GGML_LOG_ERROR("%s, ZenDNN matmul failed: status=%d\n", __func__, static_cast<int>(status));
+        return false;
+    }
+    return true;
+}
+
+static bool ggml_zendnn_sgemm(ggml_backend_zendnn_context * ctx, int64_t m, int64_t n, int64_t k,
+                              const void * A, int64_t lda, const void * B, int64_t ldb, void * C,
+                              int64_t ldc, int Atype, int Btype, int Ctype) {
+
+    assert(m >= 0);
+    assert(n >= 0);
+    assert(k >= 0);
+    assert(lda >= k);
+    assert(ldb >= k);
+    assert(ldc >= m);
+
+    // categorize types
+    switch (Atype) {
+        case GGML_TYPE_F32:
+            if (Btype != GGML_TYPE_F32 || Ctype != GGML_TYPE_F32)
+                return false;
+            return ggml_zendnn_matmul<float, float, float>(
+                ctx, m, n, k,
+                (const float *)A, lda,
+                (const float *)B, ldb,
+                (float *)C, ldc);
+        case GGML_TYPE_BF16:
+            if (Btype != GGML_TYPE_BF16)
+                return false;
+            if (Ctype == GGML_TYPE_BF16)
+                return ggml_zendnn_matmul<ggml_bf16_t, ggml_bf16_t, ggml_bf16_t>(
+                    ctx, m, n, k,
+                    (const ggml_bf16_t *)A, lda,
+                    (const ggml_bf16_t *)B, ldb,
+                    (ggml_bf16_t *)C, ldc);
+            if (Ctype == GGML_TYPE_F32)
+                return ggml_zendnn_matmul<ggml_bf16_t, ggml_bf16_t, float>(
+                    ctx, m, n, k,
+                    (const ggml_bf16_t *)A, lda,
+                    (const ggml_bf16_t *)B, ldb,
+                    (float *)C, ldc);
+            return false;
+        default:
+            return false; // unsupported type
+    }
+}
+
+static void ggml_zendnn_compute_forward_mul_mat(
+    ggml_backend_zendnn_context * ctx,
+    ggml_tensor * dst) {
+
+    const ggml_tensor * src0 = dst->src[0];  // weights
+    const ggml_tensor * src1 = dst->src[1];  // inputs
+
+    GGML_TENSOR_BINARY_OP_LOCALS
+
+    ggml_type         const vec_dot_type = ggml_get_type_traits_cpu(src0->type)->vec_dot_type;
+    ggml_from_float_t const from_float = ggml_get_type_traits_cpu(vec_dot_type)->from_float;
+
+    GGML_ASSERT(ne0 == ne01);
+    GGML_ASSERT(ne1 == ne11);
+    GGML_ASSERT(ne2 == ne12);
+    GGML_ASSERT(ne3 == ne13);
+
+    // we don't support permuted src0 or src1
+    GGML_ASSERT(nb00 == ggml_type_size(src0->type));
+    GGML_ASSERT(nb10 == ggml_type_size(src1->type));
+
+    // dst cannot be transposed or permuted
+    GGML_ASSERT(nb0 == sizeof(float));
+    GGML_ASSERT(nb0 <= nb1);
+    GGML_ASSERT(nb1 <= nb2);
+    GGML_ASSERT(nb2 <= nb3);
+
+    // broadcast factors
+    const int64_t r2 = ne12/ne02;
+    const int64_t r3 = ne13/ne03;
+
+    void * work_data = ctx->work_data.get();
+    if (src1->type != vec_dot_type) {
+        const size_t nbw1 = ggml_row_size(vec_dot_type, ne10);
+        const size_t nbw2 = nbw1 * ne11;
+        const size_t nbw3 = nbw2 * ne12;
+        const size_t desired_wsize = ne13 * nbw3;
+        if (ctx->work_size < desired_wsize) {
+            ctx->work_data.reset(new char[desired_wsize]);
+            ctx->work_size = desired_wsize;
+        }
+        work_data = ctx->work_data.get();
+
+        // #pragma omp parallel for num_threads(ctx->n_threads)
+        #pragma omp parallel for collapse(3) num_threads(ctx->n_threads) schedule(static)
+        for (int64_t i13 = 0; i13 < ne13; ++i13) {
+            for (int64_t i12 = 0; i12 < ne12; ++i12) {
+                for (int64_t i11 = 0; i11 < ne11; ++i11) {
+                    const float * src1_f32 = (float *)((char *)src1->data + i11*nb11 + i12*nb12 + i13*nb13);
+                    void * src1_conv = (char *)work_data + i11*nbw1 + i12*nbw2 + i13*nbw3;
+                    from_float(src1_f32, src1_conv, ne10);
+                }
+            }
+        }
+    }
+
+    for (int64_t i13 = 0; i13 < ne13; i13++) {
+        for (int64_t i12 = 0; i12 < ne12; i12++) {
+            const void* wdata = src1->type == vec_dot_type ? src1->data : work_data;
+            const size_t row_size = ggml_row_size(vec_dot_type, ne10);
+            if (!ggml_zendnn_sgemm(ctx,
+                                  ne01,     // m
+                                  ne11,     // n
+                                  ne10,     // k
+                                  static_cast<const char *>(src0->data) + (i12/r2)*nb02 + (i13/r3)*nb03,
+                                  ne00,     // lda
+                                  static_cast<const char *>(wdata) + (i12*ne11 + i13*ne12*ne11)*row_size,
+                                  ne10,     // ldb
+                                  static_cast<char *>(dst->data) + i12*nb2 + i13*nb3,
+                                  ne01,     // ldc
+                                  src0->type,
+                                  vec_dot_type,
+                                  dst->type))
+                GGML_ABORT("%s: ZenDNN sgemm failed\n", __func__);
+        }
+    }
+}
+
+// backend interface
+
+static const char * ggml_backend_zendnn_get_name(ggml_backend_t backend) {
+    return "ZenDNN";
+
+    GGML_UNUSED(backend);
+}
+
+static void ggml_backend_zendnn_free(ggml_backend_t backend) {
+    ggml_backend_zendnn_context * ctx = (ggml_backend_zendnn_context *)backend->context;
+    delete ctx;
+    delete backend;
+}
+
+static ggml_status ggml_backend_zendnn_graph_compute(ggml_backend_t backend, ggml_cgraph * cgraph) {
+    ggml_backend_zendnn_context * ctx = (ggml_backend_zendnn_context *)backend->context;
+
+    for (int i = 0; i < cgraph->n_nodes; i++) {
+        struct ggml_tensor * node = cgraph->nodes[i];
+
+        switch (node->op) {
+            case GGML_OP_MUL_MAT:
+                ggml_zendnn_compute_forward_mul_mat(ctx, node);
+                break;
+            case GGML_OP_NONE:
+            case GGML_OP_RESHAPE:
+            case GGML_OP_VIEW:
+            case GGML_OP_PERMUTE:
+            case GGML_OP_TRANSPOSE:
+                break;
+
+            default:
+                GGML_ABORT("%s: unsupported op %s\n", __func__, ggml_op_desc(node));
+        }
+    }
+
+    return GGML_STATUS_SUCCESS;
+
+    GGML_UNUSED(backend);
+}
+
+static struct ggml_backend_i ggml_backend_zendnn_i = {
+    /* .get_name                = */ ggml_backend_zendnn_get_name,
+    /* .free                    = */ ggml_backend_zendnn_free,
+    /* .set_tensor_async        = */ NULL,
+    /* .get_tensor_async        = */ NULL,
+    /* .cpy_tensor_async        = */ NULL,
+    /* .synchronize             = */ NULL,
+    /* .graph_plan_create       = */ NULL,
+    /* .graph_plan_free         = */ NULL,
+    /* .graph_plan_update       = */ NULL,
+    /* .graph_plan_compute      = */ NULL,
+    /* .graph_compute           = */ ggml_backend_zendnn_graph_compute,
+    /* .event_record            = */ NULL,
+    /* .event_wait              = */ NULL,
+    /* .graph_optimize          = */ NULL,
+};
+
+static ggml_guid_t ggml_backend_zendnn_guid(void) {
+    static const char * guid_str = "AMD-ZENDNN-ACCEL";
+    return reinterpret_cast<ggml_guid_t>(const_cast<char*>(guid_str));
+}
+
+ggml_backend_t ggml_backend_zendnn_init(void) {
+    ggml_backend_zendnn_context * ctx = new ggml_backend_zendnn_context;
+
+    ggml_backend_t backend = new ggml_backend {
+        /* .guid    = */ ggml_backend_zendnn_guid(),
+        /* .iface   = */ ggml_backend_zendnn_i,
+        /* .device  = */ ggml_backend_reg_dev_get(ggml_backend_zendnn_reg(), 0),
+        /* .context = */ ctx,
+    };
+
+    return backend;
+}
+
+bool ggml_backend_is_zendnn(ggml_backend_t backend) {
+    return backend != NULL && ggml_guid_matches(backend->guid, ggml_backend_zendnn_guid());
+}
+
+void ggml_backend_zendnn_set_n_threads(ggml_backend_t backend_zendnn, int n_threads) {
+    GGML_ASSERT(ggml_backend_is_zendnn(backend_zendnn));
+
+    ggml_backend_zendnn_context * ctx = (ggml_backend_zendnn_context *)backend_zendnn->context;
+    ctx->n_threads = n_threads;
+}
+
+// device interface
+static const char * ggml_backend_zendnn_device_get_name(ggml_backend_dev_t dev) {
+    return "ZenDNN";
+
+    GGML_UNUSED(dev);
+}
+/**
+ * ZenDNN is AMD's performance library providing optimized primitives and implementations
+ * for deep learning workloads on AMD CPUs. It targets improved performance for common
+ * neural network operations on AMD architectures. For more information, see:
+ * https://www.amd.com/en/developer/zendnn.html
+ */
+static const char * ggml_backend_zendnn_device_get_description(ggml_backend_dev_t dev) {
+    return "ZenDNN: AMD optimized primitives backend for GGML (optimized for AMD CPUs)";
+
+    GGML_UNUSED(dev);
+}
+
+static void ggml_backend_zendnn_device_get_memory(ggml_backend_dev_t dev, size_t * free, size_t * total) {
+    *free  = 0;
+    *total = 0;
+
+    GGML_UNUSED(dev);
+}
+
+static enum ggml_backend_dev_type ggml_backend_zendnn_device_get_type(ggml_backend_dev_t dev) {
+    return GGML_BACKEND_DEVICE_TYPE_ACCEL;
+
+    GGML_UNUSED(dev);
+}
+
+static void ggml_backend_zendnn_device_get_props(ggml_backend_dev_t dev, struct ggml_backend_dev_props * props) {
+    props->name        = ggml_backend_zendnn_device_get_name(dev);
+    props->description = ggml_backend_zendnn_device_get_description(dev);
+    props->type        = ggml_backend_zendnn_device_get_type(dev);
+    ggml_backend_zendnn_device_get_memory(dev, &props->memory_free, &props->memory_total);
+    props->caps = {
+        /* .async                = */ false,
+        /* .host_buffer          = */ false,
+        /* .buffer_from_host_ptr = */ true,
+        /* .events               = */ false
+    };
+}
+
+static ggml_backend_t ggml_backend_zendnn_device_init_backend(ggml_backend_dev_t dev, const char * params) {
+    ggml_backend_t backend = ggml_backend_zendnn_init();
+    if (backend == NULL) {
+        GGML_LOG_ERROR("%s: error: failed to initialize ZenDNN backend\n", __func__);
+        return NULL;
+    }
+
+    return backend;
+
+    GGML_UNUSED(dev);
+    GGML_UNUSED(params);
+}
+
+static ggml_backend_buffer_type_t ggml_backend_zendnn_device_get_buffer_type(ggml_backend_dev_t dev) {
+    return ggml_backend_cpu_buffer_type();
+
+    GGML_UNUSED(dev);
+}
+
+static ggml_backend_buffer_t ggml_backend_zendnn_device_buffer_from_host_ptr(ggml_backend_dev_t dev, void * ptr, size_t size, size_t max_tensor_size) {
+    return ggml_backend_cpu_buffer_from_ptr(ptr, size);
+
+    GGML_UNUSED(dev);
+    GGML_UNUSED(max_tensor_size);
+}
+
+static bool ggml_backend_zendnn_device_supports_op(ggml_backend_dev_t dev, const struct ggml_tensor * op) {
+    switch (op->op) {
+        case GGML_OP_NONE:
+        case GGML_OP_RESHAPE:
+        case GGML_OP_VIEW:
+        case GGML_OP_PERMUTE:
+        case GGML_OP_TRANSPOSE:
+            return true;
+
+        case GGML_OP_MUL_MAT:
+        {
+            const ggml_tensor * weights = op->src[0];
+            const ggml_tensor * inputs = op->src[1];
+
+            const int64_t ne10 = inputs->ne[0];
+            const int64_t ne0 = op->ne[0];
+            const int64_t ne1 = op->ne[1];
+
+            const int64_t min_batch = 1;
+            if (!ggml_is_contiguous(weights) || !ggml_is_contiguous(inputs) ||
+                ne0 < min_batch || ne1 < min_batch || ne10 < min_batch) {
+                    return false;
+            }
+            switch (weights->type) {
+                case GGML_TYPE_F32:
+                case GGML_TYPE_BF16:
+                    return true;
+                default:
+                    return false;
+            }
+        } break;
+
+        default:
+            return false;
+    }
+
+    GGML_UNUSED(dev);
+}
+
+static bool ggml_backend_zendnn_device_supports_buft(ggml_backend_dev_t dev, ggml_backend_buffer_type_t buft) {
+    return ggml_backend_buft_is_host(buft);
+
+    GGML_UNUSED(dev);
+}
+
+static const struct ggml_backend_device_i ggml_backend_zendnn_device_i = {
+    /* .get_name               = */ ggml_backend_zendnn_device_get_name,
+    /* .get_description        = */ ggml_backend_zendnn_device_get_description,
+    /* .get_memory             = */ ggml_backend_zendnn_device_get_memory,
+    /* .get_type               = */ ggml_backend_zendnn_device_get_type,
+    /* .get_props              = */ ggml_backend_zendnn_device_get_props,
+    /* .init_backend           = */ ggml_backend_zendnn_device_init_backend,
+    /* .get_buffer_type        = */ ggml_backend_zendnn_device_get_buffer_type,
+    /* .get_host_buffer_type   = */ NULL,
+    /* .buffer_from_host_ptr   = */ ggml_backend_zendnn_device_buffer_from_host_ptr,
+    /* .supports_op            = */ ggml_backend_zendnn_device_supports_op,
+    /* .supports_buft          = */ ggml_backend_zendnn_device_supports_buft,
+    /* .offload_op             = */ NULL,
+    /* .event_new              = */ NULL,
+    /* .event_free             = */ NULL,
+    /* .event_synchronize      = */ NULL,
+};
+
+// backend reg interface
+static const char * ggml_backend_zendnn_reg_get_name(ggml_backend_reg_t reg) {
+    return "ZenDNN";
+
+    GGML_UNUSED(reg);
+}
+
+static size_t ggml_backend_zendnn_reg_get_device_count(ggml_backend_reg_t reg) {
+    return 1;
+
+    GGML_UNUSED(reg);
+}
+
+static ggml_backend_dev_t ggml_backend_zendnn_reg_get_device(ggml_backend_reg_t reg, size_t index) {
+    GGML_ASSERT(index == 0);
+
+    static ggml_backend_device ggml_backend_zendnn_device = {
+        /* .iface   = */ ggml_backend_zendnn_device_i,
+        /* .reg     = */ reg,
+        /* .context = */ nullptr,
+    };
+
+    return &ggml_backend_zendnn_device;
+}
+
+static void * ggml_backend_zendnn_get_proc_address(ggml_backend_reg_t reg, const char * name) {
+    if (std::strcmp(name, "ggml_backend_set_n_threads") == 0) {
+        return (void *) ggml_backend_zendnn_set_n_threads;
+    }
+    return NULL;
+
+    GGML_UNUSED(reg);
+    GGML_UNUSED(name);
+}
+
+static const struct ggml_backend_reg_i ggml_backend_zendnn_reg_i = {
+    /* .get_name         = */ ggml_backend_zendnn_reg_get_name,
+    /* .get_device_count = */ ggml_backend_zendnn_reg_get_device_count,
+    /* .get_device       = */ ggml_backend_zendnn_reg_get_device,
+    /* .get_proc_address = */ ggml_backend_zendnn_get_proc_address,
+};
+
+ggml_backend_reg_t ggml_backend_zendnn_reg(void) {
+    static struct ggml_backend_reg ggml_backend_zendnn_reg = {
+        /* .api_version = */ GGML_BACKEND_API_VERSION,
+        /* .iface       = */ ggml_backend_zendnn_reg_i,
+        /* .context     = */ NULL,
+    };
+
+    return &ggml_backend_zendnn_reg;
+}
+
+GGML_BACKEND_DL_IMPL(ggml_backend_zendnn_reg)