Julia: add binding for runtime feature detection

julia/deps/build.jl

@@ -51,9 +51,10 @@ elseif Sys.islinux()
 end
 
 if Sys.isunix()
-  try
-    push!(CUDAPATHS, replace(strip(read(`which nvcc`, String)), "bin/nvcc", "lib64"))
-  catch
+  nvcc_path = Sys.which("nvcc")
+  if nvcc_path ≢ nothing
+    @info "Found nvcc: $nvcc_path"
+    push!(CUDAPATHS, replace(nvcc_path, "bin/nvcc", "lib64"))
   end
 end
 

julia/src/MXNet.jl

@@ -139,6 +139,7 @@ export to_graphviz
 
 include("base.jl")
 
+include("mxfeatures.jl")
 include("context.jl")
 include("util.jl")
 

julia/src/mxfeatures.jl

@@ -0,0 +1,116 @@
+# Licensed to the Apache Software Foundation (ASF) under one
+# or more contributor license agreements.  See the NOTICE file
+# distributed with this work for additional information
+# regarding copyright ownership.  The ASF licenses this file
+# to you under the Apache License, Version 2.0 (the
+# License); you may not use this file except in compliance
+# with the License.  You may obtain a copy of the License at
+#
+#   http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing,
+# software distributed under the License is distributed on an
+# AS IS BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+# KIND, either express or implied.  See the License for the
+# specific language governing permissions and limitations
+# under the License.
+
+
+# runtime detection of compile time features in the native library
+
+module MXFeatures
+
+using ..mx
+
+export Feature
+export has_feature, features_enabled
+
+@enum Feature begin
+  CUDA
+  CUDNN
+  NCCL
+  CUDA_RTC
+  TENSORRT
+  CPU_SSE
+  CPU_SSE2
+  CPU_SSE3
+  CPU_SSE4_1
+  CPU_SSE4_2
+  CPU_SSE4A
+  CPU_AVX
+  CPU_AVX2
+  OPENMP
+  SSE
+  F16C
+  JEMALLOC
+  BLAS_OPEN
+  BLAS_ATLAS
+  BLAS_MKL
+  BLAS_APPLE
+  LAPACK
+  MKLDNN
+  OPENCV
+  CAFFE
+  PROFILER
+  DIST_KVSTORE
+  CXX14
+  SIGNAL_HANDLER
+  DEBUG
+end
+
+"""
+    features_enabled()
+    features_enabled(Symbol)
+    features_enabled(String; sep = ", ")
+
+Returns a list of enabled features in the back-end
+
+
+## Examples
+
+```julia-repl
+julia> mx.features_enabled()
+8-element Array{MXNet.mx.MXFeatures.Feature,1}:
+ CPU_SSE::Feature = 5
+ CPU_SSE2::Feature = 6
+ CPU_SSE3::Feature = 7
+ CPU_SSE4_1::Feature = 8
+ CPU_SSE4_2::Feature = 9
+ CPU_AVX::Feature = 11
+ F16C::Feature = 15
+ LAPACK::Feature = 21
+
+julia> mx.features_enabled(String)
+"CPU_SSE, CPU_SSE2, CPU_SSE3, CPU_SSE4_1, CPU_SSE4_2, CPU_AVX, F16C, LAPACK"
+
+julia> mx.features_enabled(Symbol)
+8-element Array{Symbol,1}:
+ :CPU_SSE
+ :CPU_SSE2
+ :CPU_SSE3
+ :CPU_SSE4_1
+ :CPU_SSE4_2
+ :CPU_AVX
+ :F16C
+ :LAPACK
+```
+"""
+features_enabled() = filter(f -> has_feature(f), collect(instances(Feature)))
+features_enabled(::Type{String}; sep = ", ") = join(features_enabled(Symbol), sep)
+features_enabled(::Type{Symbol}) = Symbol.(features_enabled())
+
+
+"""
+    hasfeature(feature::Feature) -> Bool
+
+Check the library for compile-time feature at runtime
+"""
+function has_feature(x::Feature)
+  y = Ref{Bool}(0)
+  @mx.mxcall(:MXHasFeature, (mx.MX_uint, Ref{Bool},), mx.MX_uint(x), y)
+  y[]
+end
+
+end  # module MXFeatures
+
+using .MXFeatures