Merge branch 'master' of https://github.com/ROCm-Developer-Tools/HIP into feature_get_alignment_and_size_from_metadata
Этот коммит содержится в:
Alex Voicu
поставляемый
+47
-2
@@ -296,8 +296,53 @@ def docker_upload_dockerhub( String local_org, String image_name, String remote_
|
||||
String build_config = 'Release'
|
||||
String job_name = env.JOB_NAME.toLowerCase( )
|
||||
|
||||
// The following launches 2 builds in parallel: rocm-head and cuda-9.x
|
||||
parallel rocm_head:
|
||||
// The following launches 3 builds in parallel: rocm-head, rocm-1.9.x and cuda-9.x
|
||||
parallel rocm_1_9:
|
||||
{
|
||||
node('hip-rocm')
|
||||
{
|
||||
String hcc_ver = 'rocm-1.9.x'
|
||||
String from_image = 'ci_test_nodes/rocm-1.9.x/ubuntu-16.04:latest'
|
||||
String inside_args = '--device=/dev/kfd --device=/dev/dri --group-add=video'
|
||||
|
||||
// Checkout source code, dependencies and version files
|
||||
String source_hip_rel = checkout_and_version( hcc_ver )
|
||||
|
||||
// Create/reuse a docker image that represents the hip build environment
|
||||
def hip_build_image = docker_build_image( hcc_ver, 'hip', '', source_hip_rel, from_image )
|
||||
|
||||
// Print system information for the log
|
||||
hip_build_image.inside( inside_args )
|
||||
{
|
||||
sh """#!/usr/bin/env bash
|
||||
set -x
|
||||
/opt/rocm/bin/rocm_agent_enumerator -t ALL
|
||||
/opt/rocm/bin/hcc --version
|
||||
"""
|
||||
}
|
||||
|
||||
// Conctruct a binary directory path based on build config
|
||||
String build_hip_rel = build_directory_rel( build_config );
|
||||
|
||||
// Build hip inside of the build environment
|
||||
docker_build_inside_image( hip_build_image, inside_args, hcc_ver, '', build_config, source_hip_rel, build_hip_rel )
|
||||
|
||||
// Clean docker build image
|
||||
docker_clean_images( 'hip', docker_build_image_name( ) )
|
||||
|
||||
// After a successful build, upload a docker image of the results
|
||||
/*
|
||||
String hip_image_name = docker_upload_artifactory( hcc_ver, job_name, from_image, source_hip_rel, build_hip_rel )
|
||||
if( params.push_image_to_docker_hub )
|
||||
{
|
||||
docker_upload_dockerhub( job_name, hip_image_name, 'rocm' )
|
||||
docker_clean_images( 'rocm', hip_image_name )
|
||||
}
|
||||
docker_clean_images( job_name, hip_image_name )
|
||||
*/
|
||||
}
|
||||
},
|
||||
rocm_head:
|
||||
{
|
||||
node('hip-rocm')
|
||||
{
|
||||
|
||||
@@ -687,7 +687,11 @@ if($HIP_PLATFORM eq "hcc" or $HIP_PLATFORM eq "clang"){
|
||||
$HIPCXXFLAGS .= " -D__HIP_ARCH_GFX900__=1 ";
|
||||
}
|
||||
if ($target_gfx906 eq 1) {
|
||||
$HIPLDFLAGS .= " --amdgpu-target=gfx906";
|
||||
$GPU_ARCH_ARG = $GPU_ARCH_OPT . "gfx906";
|
||||
$HIPLDFLAGS .= $GPU_ARCH_ARG;
|
||||
if ($HIP_PLATFORM eq 'clang') {
|
||||
$HIPCXXFLAGS .= $GPU_ARCH_ARG;;
|
||||
}
|
||||
$HIPCXXFLAGS .= " -D__HIP_ARCH_GFX906__=1 ";
|
||||
}
|
||||
}
|
||||
|
||||
@@ -23,7 +23,7 @@ set(CMAKE_CXX_COMPILER ${LLVM_TOOLS_BINARY_DIR}/clang++)
|
||||
set(CMAKE_C_COMPILER ${LLVM_TOOLS_BINARY_DIR}/clang)
|
||||
|
||||
# Link against LLVM and CLANG libraries
|
||||
target_link_libraries(hipify-clang
|
||||
target_link_libraries(hipify-clang PRIVATE
|
||||
clangASTMatchers
|
||||
clangFrontend
|
||||
clangTooling
|
||||
@@ -48,11 +48,11 @@ target_link_libraries(hipify-clang
|
||||
LLVMCore)
|
||||
|
||||
if(WIN32)
|
||||
target_link_libraries(hipify-clang version)
|
||||
target_link_libraries(hipify-clang PRIVATE version)
|
||||
endif()
|
||||
|
||||
if ((LLVM_PACKAGE_VERSION VERSION_EQUAL "7") OR (LLVM_PACKAGE_VERSION VERSION_GREATER "7"))
|
||||
target_link_libraries(hipify-clang clangToolingInclusions)
|
||||
target_link_libraries(hipify-clang PRIVATE clangToolingInclusions)
|
||||
endif()
|
||||
|
||||
set(CMAKE_C_FLAGS "${CMAKE_C_FLAGS} ${EXTRA_CFLAGS}")
|
||||
|
||||
@@ -30,11 +30,7 @@
|
||||
## <a name="dependencies"></a> Dependencies
|
||||
|
||||
`hipify-clang` requires:
|
||||
1. LLVM+CLANG of at least version 3.8.0, latest stable and recommended releases:
|
||||
|
||||
6.0.1 (linux and windows),
|
||||
|
||||
7.0.0 (linux only).
|
||||
1. LLVM+CLANG of at least version 3.8.0, latest stable and recommended release: 6.0.1 (linux and windows).
|
||||
|
||||
2. CUDA at least version 7.5, latest supported release is 9.2.
|
||||
|
||||
@@ -50,8 +46,8 @@
|
||||
| 5.0.1 | 8.0 |
|
||||
| 5.0.2 | 8.0 |
|
||||
| 6.0.0 | 9.0 |
|
||||
| 6.0.1 | 9.0 |
|
||||
| 7.0.0 | 9.2 | linux only |
|
||||
| **6.0.1** | **9.0** | **LATEST STABLE RELEASE** |
|
||||
| 7.0.0 | 9.2 | windows is not supported, on linux there is a clang bug: https://bugs.llvm.org/show_bug.cgi?id=36384 |
|
||||
| | 10.0 | not yet supported |
|
||||
|
||||
In most cases, you can get a suitable version of LLVM+CLANG with your package manager.
|
||||
@@ -77,10 +73,10 @@ cmake \
|
||||
|
||||
make -j install
|
||||
```
|
||||
On Windows the following option should be specified for `cmake` at first place: `-G "Visual Studio 15 2017 Win64"` and after `cmake` the generated `hipify-clang.sln` should be built by `Visual Studio 15 2017` instead of `make`.
|
||||
On Windows, the following option should be specified for `cmake` at first place: `-G "Visual Studio 15 2017 Win64"`; the generated `hipify-clang.sln` should be built by `Visual Studio 15 2017` instead of `make.`
|
||||
|
||||
Debug build type `-DCMAKE_BUILD_TYPE=Debug` is also supported and tested, `LLVM+CLANG` should be built in `Debug` mode as well.
|
||||
64 bit build mode `-Thost=x64` is supported as well, `LLVM+CLANG` should be built (installed) in 64bit mode as well.
|
||||
Debug build type `-DCMAKE_BUILD_TYPE=Debug` is also supported and tested; `LLVM+CLANG` should be built in `Debug` mode as well.
|
||||
64 bit build mode `-Thost=x64` is supported as well; `LLVM+CLANG` should be built in 64bit mode as well.
|
||||
|
||||
The binary can then be found at `./dist/bin/hipify-clang`.
|
||||
|
||||
@@ -108,11 +104,11 @@ To run it:
|
||||
|
||||
make -j install
|
||||
```
|
||||
On Windows the following option should be specified for `cmake` at first place: `-G "Visual Studio 15 2017 Win64"` and after `cmake` the generated `LLVM.sln` should be built by `Visual Studio 15 2017` instead of `make`.
|
||||
On Windows the following option should be specified for `cmake` at first place: `-G "Visual Studio 15 2017 Win64"`; the generated `LLVM.sln` should be built by `Visual Studio 15 2017` instead of `make`.
|
||||
|
||||
3. Ensure [`CUDA`](https://developer.nvidia.com/cuda-toolkit-archive) of minimum version 7.5 is installed.
|
||||
|
||||
* Having multiple CUDA installations in order to choose a concrete version the `DCUDA_TOOLKIT_ROOT_DIR` option should be specified:
|
||||
* Having multiple CUDA installations, in order to choose a particular version the `DCUDA_TOOLKIT_ROOT_DIR` option should be specified:
|
||||
|
||||
`-DCUDA_TOOLKIT_ROOT_DIR="C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v9.0"`
|
||||
|
||||
@@ -127,7 +123,9 @@ To run it:
|
||||
`-DCUDA_DNN_ROOT_DIR=f:/CUDNN/cudnn-9.0-windows10-x64-v7.1`
|
||||
|
||||
5. Ensure [`python`](https://www.python.org/downloads) of minimum required version 2.7 is installed.
|
||||
|
||||
6. Ensure `lit` and `FileCheck` are installed - these are distributed with LLVM.
|
||||
|
||||
* installing `lit` into `python` might be required:
|
||||
|
||||
`python f:/LLVM/6.0.1/llvm/utils/lit/setup.py install`,
|
||||
@@ -139,7 +137,9 @@ To run it:
|
||||
`-DLLVM_EXTERNAL_LIT=f:/LLVM/6.0.1/build/Release/bin/llvm-lit.py`,
|
||||
|
||||
where `f:/LLVM/6.0.1/build/Release` is LLVM build directory.
|
||||
|
||||
7. Build with the `HIPIFY_CLANG_TESTS` option turned on: -DHIPIFY_CLANG_TESTS=1.
|
||||
|
||||
8. `make test-hipify`
|
||||
|
||||
On Windows after `cmake` the project `test-hipify` in the generated `hipify-clang.sln` should be built by `Visual Studio 15 2017` instead of `make test-hipify`.
|
||||
@@ -178,7 +178,7 @@ A corresponding successful output:
|
||||
-- - CMake module path: F:/LLVM/6.0.1/dist/lib/cmake/llvm
|
||||
-- - Include path : F:/LLVM/6.0.1/dist/include
|
||||
-- - Binary path : F:/LLVM/6.0.1/dist/bin
|
||||
-- Found PythonInterp: C:/Program Files/Python36/python.exe (found suitable version "3.6.4", minimum required is "2.7")
|
||||
-- Found PythonInterp: C:/Program Files/Python36/python.exe (found suitable version "3.6.4", minimum required is "3.6")
|
||||
-- Found lit: C:/Program Files/Python36/Scripts/lit.exe
|
||||
-- Found FileCheck: F:/LLVM/6.0.1/dist/bin/FileCheck.exe
|
||||
-- Found CUDA: C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v9.0 (found version "9.0")
|
||||
|
||||
@@ -297,9 +297,16 @@ float __shfl(float var, int src_lane, int width = warpSize) {
|
||||
__device__
|
||||
inline
|
||||
double __shfl(double var, int src_lane, int width = warpSize) {
|
||||
__u tmp; tmp.f = (float) var;
|
||||
tmp.i = __shfl(tmp.i, src_lane, width);
|
||||
return (double) tmp.f;
|
||||
static_assert(sizeof(double) == 2 * sizeof(int), "");
|
||||
static_assert(sizeof(double) == sizeof(uint64_t), "");
|
||||
|
||||
int tmp[2]; __builtin_memcpy(tmp, &var, sizeof(tmp));
|
||||
tmp[0] = __shfl(tmp[0], src_lane, width);
|
||||
tmp[1] = __shfl(tmp[1], src_lane, width);
|
||||
|
||||
uint64_t tmp0 = (static_cast<uint64_t>(tmp[1]) << 32ull) | static_cast<uint32_t>(tmp[0]);
|
||||
double tmp1; __builtin_memcpy(&tmp1, &tmp0, sizeof(tmp0));
|
||||
return tmp1;
|
||||
}
|
||||
|
||||
__device__
|
||||
@@ -327,9 +334,16 @@ float __shfl_up(float var, unsigned int lane_delta, int width = warpSize) {
|
||||
__device__
|
||||
inline
|
||||
double __shfl_up(double var, unsigned int lane_delta, int width = warpSize) {
|
||||
__u tmp; tmp.f = (float) var;
|
||||
tmp.i = __shfl_up(tmp.i, lane_delta, width);
|
||||
return (double) tmp.f;
|
||||
static_assert(sizeof(double) == 2 * sizeof(int), "");
|
||||
static_assert(sizeof(double) == sizeof(uint64_t), "");
|
||||
|
||||
int tmp[2]; __builtin_memcpy(tmp, &var, sizeof(tmp));
|
||||
tmp[0] = __shfl_up(tmp[0], lane_delta, width);
|
||||
tmp[1] = __shfl_up(tmp[1], lane_delta, width);
|
||||
|
||||
uint64_t tmp0 = (static_cast<uint64_t>(tmp[1]) << 32ull) | static_cast<uint32_t>(tmp[0]);
|
||||
double tmp1; __builtin_memcpy(&tmp1, &tmp0, sizeof(tmp0));
|
||||
return tmp1;
|
||||
}
|
||||
|
||||
__device__
|
||||
@@ -357,9 +371,16 @@ float __shfl_down(float var, unsigned int lane_delta, int width = warpSize) {
|
||||
__device__
|
||||
inline
|
||||
double __shfl_down(double var, unsigned int lane_delta, int width = warpSize) {
|
||||
__u tmp; tmp.f = (float) var;
|
||||
tmp.i = __shfl_down(tmp.i, lane_delta, width);
|
||||
return (double) tmp.f;
|
||||
static_assert(sizeof(double) == 2 * sizeof(int), "");
|
||||
static_assert(sizeof(double) == sizeof(uint64_t), "");
|
||||
|
||||
int tmp[2]; __builtin_memcpy(tmp, &var, sizeof(tmp));
|
||||
tmp[0] = __shfl_down(tmp[0], lane_delta, width);
|
||||
tmp[1] = __shfl_down(tmp[1], lane_delta, width);
|
||||
|
||||
uint64_t tmp0 = (static_cast<uint64_t>(tmp[1]) << 32ull) | static_cast<uint32_t>(tmp[0]);
|
||||
double tmp1; __builtin_memcpy(&tmp1, &tmp0, sizeof(tmp0));
|
||||
return tmp1;
|
||||
}
|
||||
|
||||
__device__
|
||||
@@ -387,9 +408,16 @@ float __shfl_xor(float var, int lane_mask, int width = warpSize) {
|
||||
__device__
|
||||
inline
|
||||
double __shfl_xor(double var, int lane_mask, int width = warpSize) {
|
||||
__u tmp; tmp.f = (float) var;
|
||||
tmp.i = __shfl_xor(tmp.i, lane_mask, width);
|
||||
return (double) tmp.f;
|
||||
static_assert(sizeof(double) == 2 * sizeof(int), "");
|
||||
static_assert(sizeof(double) == sizeof(uint64_t), "");
|
||||
|
||||
int tmp[2]; __builtin_memcpy(tmp, &var, sizeof(tmp));
|
||||
tmp[0] = __shfl_xor(tmp[0], lane_mask, width);
|
||||
tmp[1] = __shfl_xor(tmp[1], lane_mask, width);
|
||||
|
||||
uint64_t tmp0 = (static_cast<uint64_t>(tmp[1]) << 32ull) | static_cast<uint32_t>(tmp[0]);
|
||||
double tmp1; __builtin_memcpy(&tmp1, &tmp0, sizeof(tmp0));
|
||||
return tmp1;
|
||||
}
|
||||
|
||||
#define MASK1 0x00ff00ff
|
||||
@@ -752,6 +780,80 @@ void *__amdgcn_get_dynamicgroupbaseptr() {
|
||||
return __get_dynamicgroupbaseptr();
|
||||
}
|
||||
|
||||
#if defined(__HCC__) && (__hcc_minor__ < 3)
|
||||
// hip.amdgcn.bc - sync threads
|
||||
#define __CLK_LOCAL_MEM_FENCE 0x01
|
||||
typedef unsigned __cl_mem_fence_flags;
|
||||
|
||||
typedef enum __memory_scope {
|
||||
__memory_scope_work_item = __OPENCL_MEMORY_SCOPE_WORK_ITEM,
|
||||
__memory_scope_work_group = __OPENCL_MEMORY_SCOPE_WORK_GROUP,
|
||||
__memory_scope_device = __OPENCL_MEMORY_SCOPE_DEVICE,
|
||||
__memory_scope_all_svm_devices = __OPENCL_MEMORY_SCOPE_ALL_SVM_DEVICES,
|
||||
__memory_scope_sub_group = __OPENCL_MEMORY_SCOPE_SUB_GROUP
|
||||
} __memory_scope;
|
||||
|
||||
// enum values aligned with what clang uses in EmitAtomicExpr()
|
||||
typedef enum __memory_order
|
||||
{
|
||||
__memory_order_relaxed = __ATOMIC_RELAXED,
|
||||
__memory_order_acquire = __ATOMIC_ACQUIRE,
|
||||
__memory_order_release = __ATOMIC_RELEASE,
|
||||
__memory_order_acq_rel = __ATOMIC_ACQ_REL,
|
||||
__memory_order_seq_cst = __ATOMIC_SEQ_CST
|
||||
} __memory_order;
|
||||
|
||||
__device__
|
||||
inline
|
||||
static void
|
||||
__atomic_work_item_fence(__cl_mem_fence_flags flags, __memory_order order, __memory_scope scope)
|
||||
{
|
||||
// We're tying global-happens-before and local-happens-before together as does HSA
|
||||
if (order != __memory_order_relaxed) {
|
||||
switch (scope) {
|
||||
case __memory_scope_work_item:
|
||||
break;
|
||||
case __memory_scope_sub_group:
|
||||
switch (order) {
|
||||
case __memory_order_relaxed: break;
|
||||
case __memory_order_acquire: __llvm_fence_acq_sg(); break;
|
||||
case __memory_order_release: __llvm_fence_rel_sg(); break;
|
||||
case __memory_order_acq_rel: __llvm_fence_ar_sg(); break;
|
||||
case __memory_order_seq_cst: __llvm_fence_sc_sg(); break;
|
||||
}
|
||||
break;
|
||||
case __memory_scope_work_group:
|
||||
switch (order) {
|
||||
case __memory_order_relaxed: break;
|
||||
case __memory_order_acquire: __llvm_fence_acq_wg(); break;
|
||||
case __memory_order_release: __llvm_fence_rel_wg(); break;
|
||||
case __memory_order_acq_rel: __llvm_fence_ar_wg(); break;
|
||||
case __memory_order_seq_cst: __llvm_fence_sc_wg(); break;
|
||||
}
|
||||
break;
|
||||
case __memory_scope_device:
|
||||
switch (order) {
|
||||
case __memory_order_relaxed: break;
|
||||
case __memory_order_acquire: __llvm_fence_acq_dev(); break;
|
||||
case __memory_order_release: __llvm_fence_rel_dev(); break;
|
||||
case __memory_order_acq_rel: __llvm_fence_ar_dev(); break;
|
||||
case __memory_order_seq_cst: __llvm_fence_sc_dev(); break;
|
||||
}
|
||||
break;
|
||||
case __memory_scope_all_svm_devices:
|
||||
switch (order) {
|
||||
case __memory_order_relaxed: break;
|
||||
case __memory_order_acquire: __llvm_fence_acq_sys(); break;
|
||||
case __memory_order_release: __llvm_fence_rel_sys(); break;
|
||||
case __memory_order_acq_rel: __llvm_fence_ar_sys(); break;
|
||||
case __memory_order_seq_cst: __llvm_fence_sc_sys(); break;
|
||||
}
|
||||
break;
|
||||
}
|
||||
}
|
||||
}
|
||||
#endif
|
||||
|
||||
// Memory Fence Functions
|
||||
__device__
|
||||
inline
|
||||
|
||||
@@ -65,6 +65,29 @@ extern "C" __device__ __attribute__((const)) float __ocml_fmax_f32(float, float)
|
||||
__device__ inline static __local void* __to_local(unsigned x) { return (__local void*)x; }
|
||||
#endif //__HIP_DEVICE_COMPILE__
|
||||
|
||||
#if defined(__HCC__) && (__hcc_minor__ < 3)
|
||||
// __llvm_fence* functions from device-libs/irif/src/fence.ll
|
||||
extern "C" __device__ void __llvm_fence_acq_sg(void);
|
||||
extern "C" __device__ void __llvm_fence_acq_wg(void);
|
||||
extern "C" __device__ void __llvm_fence_acq_dev(void);
|
||||
extern "C" __device__ void __llvm_fence_acq_sys(void);
|
||||
|
||||
extern "C" __device__ void __llvm_fence_rel_sg(void);
|
||||
extern "C" __device__ void __llvm_fence_rel_wg(void);
|
||||
extern "C" __device__ void __llvm_fence_rel_dev(void);
|
||||
extern "C" __device__ void __llvm_fence_rel_sys(void);
|
||||
|
||||
extern "C" __device__ void __llvm_fence_ar_sg(void);
|
||||
extern "C" __device__ void __llvm_fence_ar_wg(void);
|
||||
extern "C" __device__ void __llvm_fence_ar_dev(void);
|
||||
extern "C" __device__ void __llvm_fence_ar_sys(void);
|
||||
|
||||
|
||||
extern "C" __device__ void __llvm_fence_sc_sg(void);
|
||||
extern "C" __device__ void __llvm_fence_sc_wg(void);
|
||||
extern "C" __device__ void __llvm_fence_sc_dev(void);
|
||||
extern "C" __device__ void __llvm_fence_sc_sys(void);
|
||||
#else
|
||||
// Using hip.amdgcn.bc - sync threads
|
||||
#define __CLK_LOCAL_MEM_FENCE 0x01
|
||||
typedef unsigned __cl_mem_fence_flags;
|
||||
@@ -90,5 +113,6 @@ typedef enum __memory_order
|
||||
// Linked from hip.amdgcn.bc
|
||||
extern "C" __device__ void
|
||||
__atomic_work_item_fence(__cl_mem_fence_flags, __memory_order, __memory_scope);
|
||||
#endif
|
||||
|
||||
#endif
|
||||
|
||||
@@ -31,12 +31,21 @@ THE SOFTWARE.
|
||||
//-------------------------------------------------------------------------------------------------
|
||||
// Stream
|
||||
//
|
||||
#if defined(__HCC__) && (__hcc_minor__ < 3)
|
||||
enum queue_priority
|
||||
{
|
||||
priority_high = 0,
|
||||
priority_normal = 0,
|
||||
priority_low = 0
|
||||
};
|
||||
#else
|
||||
enum queue_priority
|
||||
{
|
||||
priority_high = Kalmar::priority_high,
|
||||
priority_normal = Kalmar::priority_normal,
|
||||
priority_low = Kalmar::priority_low
|
||||
};
|
||||
#endif
|
||||
|
||||
//---
|
||||
hipError_t ihipStreamCreate(hipStream_t* stream, unsigned int flags, int priority) {
|
||||
@@ -59,7 +68,11 @@ hipError_t ihipStreamCreate(hipStream_t* stream, unsigned int flags, int priorit
|
||||
// Obtain mutex access to the device critical data, release by destructor
|
||||
LockedAccessor_CtxCrit_t ctxCrit(ctx->criticalData());
|
||||
|
||||
#if defined(__HCC__) && (__hcc_minor__ < 3)
|
||||
auto istream = new ihipStream_t(ctx, acc.create_view(), flags);
|
||||
#else
|
||||
auto istream = new ihipStream_t(ctx, acc.create_view(Kalmar::execute_in_order, Kalmar::queuing_mode_automatic, (Kalmar::queue_priority)priority), flags);
|
||||
#endif
|
||||
|
||||
ctxCrit->addStream(istream);
|
||||
*stream = istream;
|
||||
@@ -223,8 +236,12 @@ hipError_t hipStreamGetPriority(hipStream_t stream, int* priority) {
|
||||
} else if (stream == hipStreamNull) {
|
||||
return ihipLogStatus(hipErrorInvalidResourceHandle);
|
||||
} else {
|
||||
#if defined(__HCC__) && (__hcc_minor__ < 3)
|
||||
*priority = 0;
|
||||
#else
|
||||
LockedAccessor_StreamCrit_t crit(stream->_criticalData);
|
||||
*priority = crit->_av.get_queue_priority();
|
||||
#endif
|
||||
return ihipLogStatus(hipSuccess);
|
||||
}
|
||||
}
|
||||
|
||||
Ссылка в новой задаче
Block a user