[Experiment] ROCM backend initial push

CMakeLists.txt

@@ -35,6 +35,7 @@ option(MLX_BUILD_PYTHON_BINDINGS "Build python bindings for mlx" OFF)
 option(MLX_BUILD_METAL "Build metal backend" ON)
 option(MLX_BUILD_CPU "Build cpu backend" ON)
 option(MLX_BUILD_CUDA "Build cuda backend" OFF)
+option(MLX_BUILD_ROCM "Build ROCm backend" OFF)
 option(MLX_METAL_DEBUG "Enhance metal debug workflow" OFF)
 option(MLX_ENABLE_X64_MAC "Enable building for x64 macOS" OFF)
 option(MLX_BUILD_GGUF "Include support for GGUF format" ON)
@@ -88,6 +89,10 @@ if(MLX_BUILD_CUDA)
   enable_language(CUDA)
 endif()
 
+if(MLX_BUILD_ROCM)
+  enable_language(HIP)
+endif()
+
 if(MLX_BUILD_METAL AND NOT METAL_LIB)
   message(STATUS "Metal not found. Unable to build GPU")
   set(MLX_BUILD_METAL OFF)

mlx/CMakeLists.txt

@@ -60,7 +60,16 @@ else()
                  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/backend/cuda/no_cuda.cpp)
 endif()
 
-if(MLX_BUILD_METAL OR MLX_BUILD_CUDA)
+if(MLX_BUILD_ROCM)
+  add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backend/rocm)
+else()
+  target_sources(mlx
+                 PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/backend/rocm/no_rocm.cpp)
+endif()
+
+if(MLX_BUILD_METAL
+   OR MLX_BUILD_CUDA
+   OR MLX_BUILD_ROCM)
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backend/gpu)
 else()
   add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/backend/no_gpu)

mlx/backend/rocm/CMakeLists.txt

@@ -0,0 +1,85 @@
+# Filename rules in ROCm backend:
+#
+# * Use .hip/.hpp if code contains device code, and .cpp/.h if not.
+# * Device-only code should be put in device/ subdir.
+# * Files in device/ subdir should not include files outside.
+target_sources(
+  mlx
+  PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/allocator.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/arg_reduce.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/binary.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/compiled.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/copy.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/device.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/eval.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/event.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/fence.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/indexing.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/kernel_utils.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/matmul.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/layer_norm.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/logsumexp.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/primitives.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/random.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/reduce.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/rms_norm.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/rope.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/rocm.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/slicing.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/softmax.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/sort.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/ternary.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/unary.hip
+          ${CMAKE_CURRENT_SOURCE_DIR}/utils.cpp
+          ${CMAKE_CURRENT_SOURCE_DIR}/worker.cpp)
+
+target_compile_definitions(mlx PRIVATE MLX_USE_ROCM)
+
+# Embed kernel sources in binary for JIT compilation.
+file(
+  GLOB MLX_JIT_SOURCES
+  RELATIVE ${CMAKE_CURRENT_SOURCE_DIR}
+  "${CMAKE_CURRENT_SOURCE_DIR}/device/*.h"
+  "${CMAKE_CURRENT_SOURCE_DIR}/device/*.hpp")
+string(JOIN ":" MLX_JIT_SOURCES_ARG ${MLX_JIT_SOURCES})
+add_custom_command(
+  OUTPUT gen/rocm_jit_sources.h
+  COMMAND
+    ${CMAKE_COMMAND} -DMLX_SOURCE_ROOT=${CMAKE_CURRENT_SOURCE_DIR}
+    -DMLX_JIT_SOURCES=${MLX_JIT_SOURCES_ARG} -P
+    "${CMAKE_CURRENT_SOURCE_DIR}/bin2h.cmake"
+  DEPENDS bin2h.cmake ${MLX_JIT_SOURCES})
+add_custom_target(rocm_jit_sources DEPENDS gen/rocm_jit_sources.h)
+add_dependencies(mlx rocm_jit_sources)
+target_include_directories(mlx PRIVATE "${CMAKE_CURRENT_BINARY_DIR}/gen")
+
+# Find ROCm installation
+find_package(hip REQUIRED)
+find_package(rocblas REQUIRED)
+
+# Link with ROCm libraries
+target_link_libraries(mlx PRIVATE hip::device roc::rocblas)
+
+# Set GPU architectures for ROCm Common ROCm architectures: gfx900, gfx906,
+# gfx908, gfx90a, gfx1030, gfx1100
+set(MLX_ROCM_ARCHITECTURES
+    "gfx900;gfx906;gfx908;gfx90a;gfx1030;gfx1100"
+    CACHE STRING "ROCm GPU architectures")
+message(STATUS "ROCm GPU architectures: ${MLX_ROCM_ARCHITECTURES}")
+
+# Set GPU targets for HIP compilation
+set_property(TARGET mlx PROPERTY HIP_ARCHITECTURES "${MLX_ROCM_ARCHITECTURES}")
+
+# Enable HIP language support
+enable_language(HIP)
+
+# Set HIP compiler flags
+target_compile_options(
+  mlx
+  PRIVATE "$<$<COMPILE_LANGUAGE:HIP>:-fgpu-rdc>"
+          "$<$<COMPILE_LANGUAGE:HIP>:-Xcompiler=-Wall>"
+          "$<$<COMPILE_LANGUAGE:HIP>:-Xcompiler=-Wextra>")
+
+# Add ROCm include directories
+target_include_directories(mlx PRIVATE ${hip_INCLUDE_DIRS})
+target_include_directories(mlx PRIVATE ${rocblas_INCLUDE_DIRS})

mlx/backend/rocm/allocator.cpp

@@ -0,0 +1,20 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/allocator.h"
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+void* allocate(size_t size) {
+  void* ptr;
+  check_hip_error("hipMalloc", hipMalloc(&ptr, size));
+  return ptr;
+}
+
+void deallocate(void* ptr) {
+  if (ptr) {
+    check_hip_error("hipFree", hipFree(ptr));
+  }
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/allocator.h

@@ -0,0 +1,12 @@
+// Copyright © 2025 Apple Inc.
+
+#pragma once
+
+#include <cstddef>
+
+namespace mlx::core::rocm {
+
+void* allocate(size_t size);
+void deallocate(void* ptr);
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/arg_reduce.hip

@@ -0,0 +1,28 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void argmax_kernel(float* input, int* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  
+  // Simple argmax placeholder
+  if (idx == 0) {
+    int max_idx = 0;
+    float max_val = input[0];
+    for (int i = 1; i < n; i++) {
+      if (input[i] > max_val) {
+        max_val = input[i];
+        max_idx = i;
+      }
+    }
+    output[0] = max_idx;
+  }
+}
+
+void launch_argmax(float* input, int* output, int n, hipStream_t stream) {
+  hipLaunchKernelGGL(argmax_kernel, dim3(1), dim3(1), 0, stream, input, output, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/bin2h.cmake

@@ -0,0 +1,47 @@
+# Copyright © 2025 Apple Inc.
+
+# Script to embed kernel source files as header for JIT compilation
+
+set(MLX_OUTPUT_FILE "${CMAKE_CURRENT_BINARY_DIR}/gen/rocm_jit_sources.h")
+set(MLX_KERNEL_HEADER
+    "#pragma once\n\n#include <unordered_map>\n#include <string>\n\nnamespace mlx::core::rocm {\n\n"
+)
+set(MLX_KERNEL_FOOTER "\n} // namespace mlx::core::rocm\n")
+
+# Create output directory
+get_filename_component(MLX_OUTPUT_DIR ${MLX_OUTPUT_FILE} DIRECTORY)
+file(MAKE_DIRECTORY ${MLX_OUTPUT_DIR})
+
+# Write header
+file(WRITE ${MLX_OUTPUT_FILE} ${MLX_KERNEL_HEADER})
+
+# Process JIT sources
+string(REPLACE ":" ";" MLX_JIT_SOURCES_LIST ${MLX_JIT_SOURCES})
+
+set(MLX_SOURCE_MAP
+    "const std::unordered_map<std::string, std::string> kernel_sources = {\n")
+
+foreach(source IN LISTS MLX_JIT_SOURCES_LIST)
+  set(source_file "${MLX_SOURCE_ROOT}/${source}")
+  if(EXISTS ${source_file})
+    # Read source file
+    file(READ ${source_file} source_content)
+
+    # Escape content for C++ string literal
+    string(REPLACE "\\" "\\\\" source_content "${source_content}")
+    string(REPLACE "\"" "\\\"" source_content "${source_content}")
+    string(REPLACE "\n" "\\n\"\n\"" source_content "${source_content}")
+
+    # Add to map
+    set(MLX_SOURCE_MAP
+        "${MLX_SOURCE_MAP}  {\"${source}\", \"${source_content}\"},\n")
+  endif()
+endforeach()
+
+set(MLX_SOURCE_MAP "${MLX_SOURCE_MAP}};\n")
+
+# Write source map
+file(APPEND ${MLX_OUTPUT_FILE} ${MLX_SOURCE_MAP})
+
+# Write footer
+file(APPEND ${MLX_OUTPUT_FILE} ${MLX_KERNEL_FOOTER})

mlx/backend/rocm/binary.hip

@@ -0,0 +1,36 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+// Basic binary operation kernels will go here
+__global__ void add_kernel(float* a, float* b, float* c, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    c[idx] = a[idx] + b[idx];
+  }
+}
+
+__global__ void multiply_kernel(float* a, float* b, float* c, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    c[idx] = a[idx] * b[idx];
+  }
+}
+
+void launch_add(float* a, float* b, float* c, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(add_kernel, dim3(blocks), dim3(threads), 0, stream, a, b, c, n);
+}
+
+void launch_multiply(float* a, float* b, float* c, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(multiply_kernel, dim3(blocks), dim3(threads), 0, stream, a, b, c, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/compiled.cpp

@@ -0,0 +1,9 @@
+// Copyright © 2025 Apple Inc.
+
+namespace mlx::core::rocm {
+
+void compile() {
+  // Placeholder for ROCm compilation
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/copy.hip

@@ -0,0 +1,20 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void copy_kernel(float* src, float* dst, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    dst[idx] = src[idx];
+  }
+}
+
+void launch_copy(float* src, float* dst, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(copy_kernel, dim3(blocks), dim3(threads), 0, stream, src, dst, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/device.cpp

@@ -0,0 +1,104 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/device.h"
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+DeviceStream::DeviceStream(Device& device) : device_(device) {
+  check_hip_error("hipStreamCreate", hipStreamCreate(&stream_));
+  encoder_ = std::make_unique<CommandEncoder>(*this);
+}
+
+void DeviceStream::synchronize() {
+  check_hip_error("hipStreamSynchronize", hipStreamSynchronize(stream_));
+}
+
+hipStream_t DeviceStream::schedule_hip_stream() {
+  return stream_;
+}
+
+hipStream_t DeviceStream::last_hip_stream() {
+  return stream_;
+}
+
+CommandEncoder& DeviceStream::get_encoder() {
+  return *encoder_;
+}
+
+Device::Device(int device) : device_(device) {
+  check_hip_error("hipSetDevice", hipSetDevice(device_));
+
+  // Get device properties
+  hipDeviceProp_t prop;
+  check_hip_error(
+      "hipGetDeviceProperties", hipGetDeviceProperties(&prop, device_));
+  compute_capability_major_ = prop.major;
+  compute_capability_minor_ = prop.minor;
+
+  // Create rocBLAS handle
+  check_hip_error(
+      "rocblas_create_handle",
+      static_cast<hipError_t>(rocblas_create_handle(&rocblas_handle_)));
+}
+
+Device::~Device() {
+  if (rocblas_handle_) {
+    rocblas_destroy_handle(rocblas_handle_);
+  }
+}
+
+void Device::make_current() {
+  check_hip_error("hipSetDevice", hipSetDevice(device_));
+}
+
+DeviceStream& Device::get_stream(Stream s) {
+  auto it = streams_.find(s.index);
+  if (it != streams_.end()) {
+    return it->second;
+  }
+
+  auto [new_it, inserted] = streams_.emplace(s.index, DeviceStream(*this));
+  return new_it->second;
+}
+
+CommandEncoder::CommandEncoder(DeviceStream& stream)
+    : device_(stream.device()), stream_(stream), worker_() {}
+
+void CommandEncoder::add_completed_handler(std::function<void()> task) {
+  worker_.enqueue(task);
+}
+
+void CommandEncoder::end_encoding() {
+  // Implementation for ending encoding
+}
+
+void CommandEncoder::commit() {
+  worker_.commit();
+}
+
+// Global device management
+static std::unordered_map<int, std::unique_ptr<Device>> devices_;
+
+Device& device(mlx::core::Device device) {
+  auto it = devices_.find(device.index);
+  if (it != devices_.end()) {
+    return *it->second;
+  }
+
+  auto new_device = std::make_unique<Device>(device.index);
+  Device& dev_ref = *new_device;
+  devices_[device.index] = std::move(new_device);
+  return dev_ref;
+}
+
+DeviceStream& get_stream(Stream s) {
+  // Use default device (index 0) for now
+  return device(mlx::core::Device{mlx::core::Device::gpu, 0}).get_stream(s);
+}
+
+CommandEncoder& get_command_encoder(Stream s) {
+  return get_stream(s).get_encoder();
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/device.h

@@ -0,0 +1,141 @@
+// Copyright © 2025 Apple Inc.
+
+#pragma once
+
+#include "mlx/array.h"
+#include "mlx/backend/rocm/worker.h"
+#include "mlx/stream.h"
+
+#include <hip/hip_runtime.h>
+#include <rocblas/rocblas.h>
+
+#include <unordered_map>
+
+namespace mlx::core::rocm {
+
+class Device;
+class CommandEncoder;
+
+class DeviceStream {
+ public:
+  explicit DeviceStream(Device& device);
+
+  DeviceStream(const DeviceStream&) = delete;
+  DeviceStream& operator=(const DeviceStream&) = delete;
+
+  // Wait until kernels in the stream complete.
+  void synchronize();
+
+  // Return a HIP stream for launching kernels.
+  hipStream_t schedule_hip_stream();
+
+  // Return the last HIP stream used.
+  hipStream_t last_hip_stream();
+
+  CommandEncoder& get_encoder();
+
+  Device& device() {
+    return device_;
+  }
+
+ private:
+  Device& device_;
+  HipStream stream_;
+  std::unique_ptr<CommandEncoder> encoder_;
+};
+
+class Device {
+ public:
+  explicit Device(int device);
+  ~Device();
+
+  Device(const Device&) = delete;
+  Device& operator=(const Device&) = delete;
+
+  // Make this device the current HIP device, required by some HIP calls.
+  void make_current();
+
+  DeviceStream& get_stream(Stream s);
+
+  int hip_device() const {
+    return device_;
+  }
+  int compute_capability_major() const {
+    return compute_capability_major_;
+  }
+  int compute_capability_minor() const {
+    return compute_capability_minor_;
+  }
+  rocblas_handle rocblas_handle() const {
+    return rocblas_handle_;
+  }
+
+ private:
+  int device_;
+  int compute_capability_major_;
+  int compute_capability_minor_;
+  rocblas_handle rocblas_handle_;
+  std::unordered_map<int, DeviceStream> streams_;
+};
+
+class CommandEncoder {
+ public:
+  explicit CommandEncoder(DeviceStream& stream);
+
+  CommandEncoder(const CommandEncoder&) = delete;
+  CommandEncoder& operator=(const CommandEncoder&) = delete;
+
+  void set_input_array(const array& arr) {}
+  void set_output_array(const array& arr) {}
+
+  void add_temporary(const array& arr) {
+    temporaries_.push_back(arr.data_shared_ptr());
+  }
+
+  void add_completed_handler(std::function<void()> task);
+  void end_encoding();
+  void commit();
+
+  // Schedule a HIP stream for |fun| to launch kernels, and check error
+  // afterwards.
+  template <typename F>
+  void launch_kernel(F&& fun) {
+    launch_kernel(stream_.schedule_hip_stream(), std::forward<F>(fun));
+  }
+
+  template <typename F>
+  void launch_kernel(hipStream_t stream, F&& fun) {
+    device_.make_current();
+    fun(stream);
+    check_hip_error("kernel launch", hipGetLastError());
+    has_gpu_work_ = true;
+  }
+
+  Device& device() {
+    return device_;
+  }
+
+  DeviceStream& stream() {
+    return stream_;
+  }
+
+  bool has_gpu_work() const {
+    return has_gpu_work_;
+  }
+
+ private:
+  Device& device_;
+  DeviceStream& stream_;
+  Worker worker_;
+  bool has_gpu_work_{false};
+  std::vector<std::shared_ptr<array::Data>> temporaries_;
+};
+
+Device& device(mlx::core::Device device);
+DeviceStream& get_stream(Stream s);
+CommandEncoder& get_command_encoder(Stream s);
+
+// Utility function to check HIP errors
+void check_hip_error(const char* msg, hipError_t error);
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/eval.cpp

@@ -0,0 +1,11 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+void eval() {
+  // Placeholder for ROCm evaluation
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/event.hip

@@ -0,0 +1,32 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+class Event {
+public:
+  Event() {
+    check_hip_error("hipEventCreate", hipEventCreate(&event_));
+  }
+  
+  ~Event() {
+    hipEventDestroy(event_);
+  }
+  
+  void record(hipStream_t stream) {
+    check_hip_error("hipEventRecord", hipEventRecord(event_, stream));
+  }
+  
+  void wait() {
+    check_hip_error("hipEventSynchronize", hipEventSynchronize(event_));
+  }
+  
+  hipEvent_t event() const { return event_; }
+
+private:
+  hipEvent_t event_;
+};
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/fence.cpp

@@ -0,0 +1,9 @@
+// Copyright © 2025 Apple Inc.
+
+namespace mlx::core::rocm {
+
+void fence() {
+  // Placeholder for ROCm fence operation
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/indexing.cpp

@@ -0,0 +1,9 @@
+// Copyright © 2025 Apple Inc.
+
+namespace mlx::core::rocm {
+
+void index() {
+  // Placeholder for ROCm indexing operation
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/kernel_utils.hip

@@ -0,0 +1,29 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+// Utility functions for HIP kernels
+
+__device__ inline int get_global_id() {
+  return blockIdx.x * blockDim.x + threadIdx.x;
+}
+
+__device__ inline int get_local_id() {
+  return threadIdx.x;
+}
+
+__device__ inline int get_group_id() {
+  return blockIdx.x;
+}
+
+__device__ inline int get_local_size() {
+  return blockDim.x;
+}
+
+__device__ inline int get_num_groups() {
+  return gridDim.x;
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/layer_norm.hip

@@ -0,0 +1,37 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void layer_norm_kernel(
+    float* input, 
+    float* output, 
+    float* gamma, 
+    float* beta, 
+    int n, 
+    float eps) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  
+  if (idx < n) {
+    // Simplified layer norm placeholder
+    // Real implementation would compute mean and variance
+    output[idx] = gamma[idx] * input[idx] + beta[idx];
+  }
+}
+
+void launch_layer_norm(
+    float* input, 
+    float* output, 
+    float* gamma, 
+    float* beta, 
+    int n, 
+    float eps, 
+    hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(layer_norm_kernel, dim3(blocks), dim3(threads), 0, stream, 
+                     input, output, gamma, beta, n, eps);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/logsumexp.hip

@@ -0,0 +1,13 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void logsumexp_kernel(float* input, float* output, int n) {
+  // Placeholder implementation
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  (void)input; (void)output; (void)n; (void)idx;
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/matmul.cpp

@@ -0,0 +1,30 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/device.h"
+#include "mlx/backend/rocm/utils.h"
+
+namespace mlx::core::rocm {
+
+void matmul_hip(
+    float* a,
+    float* b,
+    float* c,
+    int m,
+    int n,
+    int k,
+    hipStream_t stream) {
+  // This is a placeholder - in a real implementation, this would use rocBLAS
+  // auto& device = get_current_device();
+  // rocblas_sgemm(device.rocblas_handle(), ...);
+
+  // For now, just a placeholder
+  (void)a;
+  (void)b;
+  (void)c;
+  (void)m;
+  (void)n;
+  (void)k;
+  (void)stream;
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/no_rocm.cpp

@@ -0,0 +1,11 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/rocm.h"
+
+namespace mlx::core::rocm {
+
+bool is_available() {
+  return false;
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/primitives.hip

@@ -0,0 +1,21 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+#include "mlx/backend/rocm/utils.h"
+#include "mlx/backend/common/primitives.h"
+
+namespace mlx::core::rocm {
+
+// Basic kernel implementations will go here
+// This is a placeholder for ROCm-specific primitive operations
+
+void add_hip() {
+  // Placeholder for HIP add operation
+}
+
+void multiply_hip() {
+  // Placeholder for HIP multiply operation  
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/random.hip

@@ -0,0 +1,23 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void random_uniform_kernel(float* output, int n, unsigned int seed) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    // Simple LCG placeholder - real implementation would use rocRAND
+    unsigned int state = seed + idx;
+    state = state * 1103515245 + 12345;
+    output[idx] = (float)(state & 0x7FFFFFFF) / (float)0x7FFFFFFF;
+  }
+}
+
+void launch_random_uniform(float* output, int n, unsigned int seed, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(random_uniform_kernel, dim3(blocks), dim3(threads), 0, stream, output, n, seed);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/reduce.hip

@@ -0,0 +1,24 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void sum_reduce_kernel(float* input, float* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  
+  // Simple reduction placeholder
+  if (idx == 0) {
+    float sum = 0.0f;
+    for (int i = 0; i < n; i++) {
+      sum += input[i];
+    }
+    output[0] = sum;
+  }
+}
+
+void launch_sum_reduce(float* input, float* output, int n, hipStream_t stream) {
+  hipLaunchKernelGGL(sum_reduce_kernel, dim3(1), dim3(1), 0, stream, input, output, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/rms_norm.hip

@@ -0,0 +1,13 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void rms_norm_kernel(float* input, float* output, int n) {
+  // Placeholder implementation
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  (void)input; (void)output; (void)n; (void)idx;
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/rocm.cpp

@@ -0,0 +1,11 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/rocm.h"
+
+namespace mlx::core::rocm {
+
+bool is_available() {
+  return true;
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/rocm.h

@@ -0,0 +1,10 @@
+// Copyright © 2025 Apple Inc.
+
+#pragma once
+
+namespace mlx::core::rocm {
+
+/* Check if the ROCm backend is available. */
+bool is_available();
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/rope.hip

@@ -0,0 +1,13 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void rope_kernel(float* input, float* output, int n) {
+  // Placeholder for RoPE implementation
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  (void)input; (void)output; (void)n; (void)idx;
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/slicing.cpp

@@ -0,0 +1,9 @@
+// Copyright © 2025 Apple Inc.
+
+namespace mlx::core::rocm {
+
+void slice() {
+  // Placeholder for ROCm slicing operation
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/softmax.hip

@@ -0,0 +1,22 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void softmax_kernel(float* input, float* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  
+  if (idx < n) {
+    // Simplified softmax placeholder - real implementation needs reduction
+    output[idx] = expf(input[idx]);
+  }
+}
+
+void launch_softmax(float* input, float* output, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(softmax_kernel, dim3(blocks), dim3(threads), 0, stream, input, output, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/sort.hip

@@ -0,0 +1 @@
+ 

mlx/backend/rocm/ternary.hip

@@ -0,0 +1,20 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void select_kernel(float* condition, float* a, float* b, float* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    output[idx] = (condition[idx] != 0.0f) ? a[idx] : b[idx];
+  }
+}
+
+void launch_select(float* condition, float* a, float* b, float* output, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(select_kernel, dim3(blocks), dim3(threads), 0, stream, condition, a, b, output, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/unary.hip

@@ -0,0 +1,33 @@
+// Copyright © 2025 Apple Inc.
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+__global__ void relu_kernel(float* input, float* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    output[idx] = fmaxf(0.0f, input[idx]);
+  }
+}
+
+__global__ void sigmoid_kernel(float* input, float* output, int n) {
+  int idx = blockIdx.x * blockDim.x + threadIdx.x;
+  if (idx < n) {
+    output[idx] = 1.0f / (1.0f + expf(-input[idx]));
+  }
+}
+
+void launch_relu(float* input, float* output, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(relu_kernel, dim3(blocks), dim3(threads), 0, stream, input, output, n);
+}
+
+void launch_sigmoid(float* input, float* output, int n, hipStream_t stream) {
+  int threads = 256;
+  int blocks = (n + threads - 1) / threads;
+  hipLaunchKernelGGL(sigmoid_kernel, dim3(blocks), dim3(threads), 0, stream, input, output, n);
+}
+
+} // namespace mlx::core::rocm 

mlx/backend/rocm/utils.cpp

@@ -0,0 +1,17 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/utils.h"
+#include <sstream>
+#include <stdexcept>
+
+namespace mlx::core::rocm {
+
+void check_hip_error(const char* msg, hipError_t error) {
+  if (error != hipSuccess) {
+    std::ostringstream oss;
+    oss << "[ROCm] " << msg << ": " << hipGetErrorString(error);
+    throw std::runtime_error(oss.str());
+  }
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/utils.h

@@ -0,0 +1,12 @@
+// Copyright © 2025 Apple Inc.
+
+#pragma once
+
+#include <hip/hip_runtime.h>
+
+namespace mlx::core::rocm {
+
+// Utility function to check HIP errors
+void check_hip_error(const char* msg, hipError_t error);
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/worker.cpp

@@ -0,0 +1,61 @@
+// Copyright © 2025 Apple Inc.
+
+#include "mlx/backend/rocm/worker.h"
+
+namespace mlx::core::rocm {
+
+Worker::Worker() : worker_thread_(&Worker::worker_loop, this) {}
+
+Worker::~Worker() {
+  {
+    std::lock_guard<std::mutex> lock(mutex_);
+    stop_ = true;
+  }
+  cv_.notify_all();
+  if (worker_thread_.joinable()) {
+    worker_thread_.join();
+  }
+}
+
+void Worker::enqueue(std::function<void()> task) {
+  {
+    std::lock_guard<std::mutex> lock(mutex_);
+    tasks_.push(task);
+  }
+  cv_.notify_one();
+}
+
+void Worker::commit() {
+  std::lock_guard<std::mutex> lock(mutex_);
+  committed_ = true;
+}
+
+void Worker::join() {
+  std::unique_lock<std::mutex> lock(mutex_);
+  cv_.wait(lock, [this] { return tasks_.empty() && committed_; });
+}
+
+void Worker::worker_loop() {
+  while (true) {
+    std::function<void()> task;
+    {
+      std::unique_lock<std::mutex> lock(mutex_);
+      cv_.wait(lock, [this] { return stop_ || !tasks_.empty(); });
+
+      if (stop_) {
+        break;
+      }
+
+      if (!tasks_.empty()) {
+        task = tasks_.front();
+        tasks_.pop();
+      }
+    }
+
+    if (task) {
+      task();
+    }
+  }
+}
+
+} // namespace mlx::core::rocm

mlx/backend/rocm/worker.h

@@ -0,0 +1,38 @@
+// Copyright © 2025 Apple Inc.
+
+#pragma once
+
+#include <hip/hip_runtime.h>
+#include <functional>
+#include <future>
+#include <queue>
+#include <thread>
+
+namespace mlx::core::rocm {
+
+using HipStream = hipStream_t;
+
+class Worker {
+ public:
+  Worker();
+  ~Worker();
+
+  Worker(const Worker&) = delete;
+  Worker& operator=(const Worker&) = delete;
+
+  void enqueue(std::function<void()> task);
+  void commit();
+  void join();
+
+ private:
+  void worker_loop();
+
+  std::thread worker_thread_;
+  std::queue<std::function<void()>> tasks_;
+  std::mutex mutex_;
+  std::condition_variable cv_;
+  bool stop_{false};
+  bool committed_{false};
+};
+
+} // namespace mlx::core::rocm

mlx/device.cpp

@@ -6,10 +6,23 @@
 #include "mlx/backend/gpu/available.h"
 #include "mlx/device.h"
 
+#ifdef MLX_USE_ROCM
+#include "mlx/backend/rocm/rocm.h"
+#endif
+
 namespace mlx::core {
 
 Device& mutable_default_device() {
-  static Device default_device{gpu::is_available() ? Device::gpu : Device::cpu};
+  Device::DeviceType default_type = Device::cpu;
+  if (gpu::is_available()) {
+    default_type = Device::gpu;
+  }
+#ifdef MLX_USE_ROCM
+  else if (rocm::is_available()) {
+    default_type = Device::gpu; // ROCm devices use the generic gpu type
+  }
+#endif
+  static Device default_device{default_type};
   return default_device;
 }
 
@@ -38,7 +51,11 @@ bool is_available(const Device& d) {
     case Device::cpu:
       return cpu::is_available();
     case Device::gpu:
+#ifdef MLX_USE_ROCM
+      return gpu::is_available() || rocm::is_available();
+#else
       return gpu::is_available();
+#endif
   }
   // appease compiler
   return false;