IVGCVSW-6755 Integrate DriverOptions to arm-armnn-sl

* Modify DriverOptions to parse an environment variable.
* Update support library service to use the new driver options.
* Added minimal README file to describe usage.

Signed-off-by: Colm Donelan <colm.donelan@arm.com>
Change-Id: Ifc2847a32bf8009c61df4465accd1b1df31f45db

5 files changed, 93 insertions, 25 deletions

diff --git a/shim/sl/README.md b/shim/sl/README.md
new file mode 100644
index 0000000000..46509656f7
--- /dev/null
+++ b/shim/sl/README.md
@@ -0,0 +1,38 @@
+# Arm NN Support Library Neural Networks driver
+
+This directory contains the Arm NN Support Library for the Android Neural Networks API.
+
+# Passing parameters to the support library runtime.
+
+The support library inherits it's parameters from the Arm NN Android Neural Networks driver. Parameters are passed to it through an environment variable, ARMNN_SL_OPTIONS. A full list of parameters are available ./canonical/DriverOptions.cpp.
+
+# Sample usage
+
+## Running NeuralNetworksSupportLibraryTest
+
+This test suite takes as it's first argument the path to a shared object implementation of the support library. Any library dependencies should be resolvable through the LD_LIBRARY_PATH mechanism. Setting ARMNN_SL_OPTIONS will pass parameters to the Arm NN Support Library Neural Networks driver.
+
+Here we assume that Bash is the current shell and specify "-v" to enable verbose logging and "-c CpuAcc" to direct that the Neon(TM) accelerator be used.
+~~~
+ARMNN_SL_OPTIONS="-v -c CpuAcc" ./NeuralNetworksSupportLibraryTest ./libarmnn_support_library.so
+~~~
+
+## Running TfLite Benchmarking tool
+
+This tools' parameters are described [here](https://www.tensorflow.org/lite/performance/measurement). The support library specific parts are to specify the path to the library and to ensure that ARMNN_SL_OPTIONS is set in the environment.
+
+support for relaxed computation from Float32 to Float16"
+~~~
+ARMNN_SL_OPTIONS="-v -c GpuAcc -f" ./android_aarch64_benchmark_model --graph=./mymodel.tflite --num_threads=1 --use_nnapi=true --num_runs=1 --nnapi_support_library_path=./libarmnn_support_library.so --nnapi_accelerator_name=arm-armnn-sl
+~~~
+
+### License
+
+The Arm NN Support Library Neural Networks driver is provided under the [MIT](https://spdx.org/licenses/MIT.html) license.
+See [LICENSE](LICENSE) for more information. Contributions to this project are accepted under the same license.
+
+Individual files contain the following tag instead of the full license text.
+
+    SPDX-License-Identifier: MIT
+
+This enables machine processing of license information based on the SPDX License Identifiers that are available here: http://spdx.org/licenses/
diff --git a/shim/sl/canonical/ArmnnDevice.cpp b/shim/sl/canonical/ArmnnDevice.cpp
index 2fc7ff1d12..3fd192630b 100644
--- a/shim/sl/canonical/ArmnnDevice.cpp
+++ b/shim/sl/canonical/ArmnnDevice.cpp
@@ -40,6 +40,20 @@ ArmnnDevice::ArmnnDevice(DriverOptions options)
     , m_ClTunedParameters(nullptr)
     , m_Options(std::move(options))
 {
+    // First check if the DriverOptions is happy.
+    if (options.ShouldExit())
+    {
+        // Is this a good or bad exit?
+        if (options.GetExitCode() != EXIT_SUCCESS)
+        {
+            throw armnn::InvalidArgumentException("ArmnnDevice: Insufficient or illegal options specified.");
+        }
+        else
+        {
+            throw armnn::InvalidArgumentException("ArmnnDevice: Nothing to do.");
+        }
+    }
+
     initVLogMask();
     VLOG(DRIVER) << "ArmnnDevice::ArmnnDevice()";
 
diff --git a/shim/sl/canonical/DriverOptions.cpp b/shim/sl/canonical/DriverOptions.cpp
index 3e26959dc1..5c73edfaa6 100644
--- a/shim/sl/canonical/DriverOptions.cpp
+++ b/shim/sl/canonical/DriverOptions.cpp
@@ -71,7 +71,10 @@ DriverOptions::DriverOptions(const std::vector<armnn::BackendId>& backends, bool
 {
 }
 
-DriverOptions::DriverOptions(int argc, char** argv)
+// This default constructor will example an environment variable called
+// ARMNN_SL_OPTIONS.  It will parse the parameters using the existing cxx
+// opts mechanism.
+DriverOptions::DriverOptions()
     : m_VerboseLogging(false)
     , m_RequestInputsAndOutputsDumpDir(std::string(""))
     , m_ServiceName(std::string("armnn_sl"))
@@ -91,11 +94,37 @@ DriverOptions::DriverOptions(int argc, char** argv)
     std::string clTunedParametersModeAsString;
     std::string clTuningLevelAsString;
     std::vector<std::string> backends;
-    bool showHelp;
-    bool showVersion;
+    bool showHelp = false;
+    bool showVersion = false;
 
-    cxxopts::Options optionsDesc(argv[0], "ArmNN Android NN driver for the Android Neural Networks API."
-                                          "The Android NN driver will convert Android NNAPI requests "
+    const char* rawEnv = std::getenv("ARMNN_SL_OPTIONS");
+    // If the environment variable isn't set we'll continue as if it were an empty string.
+    if (!rawEnv)
+    {
+        rawEnv = "";
+    }
+    string optionsAsString(rawEnv);
+    regex whiteSpaceRegex("\\s+");
+    // Tokienize the string based on whitespace.
+    sregex_token_iterator iter(optionsAsString.begin(), optionsAsString.end(), whiteSpaceRegex, -1);  
+    sregex_token_iterator end;
+    vector<string> cliAsVector(iter, end);
+    // As we're pretending to be a command line, argv[0] should be an executable name.
+    cliAsVector.insert(cliAsVector.begin(), "ARMNN_SL_OPTIONS");
+    // Convert the vector of string to a vector of char* backed by the existing vector.
+    std::vector<char*> argVector;
+    for (const auto& arg : cliAsVector)
+    {
+        argVector.push_back((char*)arg.data());
+    }
+    // Terminate the array.
+    argVector.push_back(nullptr);
+    // Create usable variables.
+    int argc = argVector.size() - 1; // Ignore the null pointer at the end.
+    char** argv = argVector.data();
+
+    cxxopts::Options optionsDesc(argv[0], "Arm NN Support Library for the Android Neural Networks API."
+                                          "The support library will convert Android NNAPI requests "
                                           "and delegate them to available ArmNN backends.");
     try
     {
@@ -118,7 +147,7 @@ DriverOptions::DriverOptions(int argc, char** argv)
          cxxopts::value<bool>(m_fp16Enabled)->default_value("false"))
 
         ("h,help", "Show this help",
-         cxxopts::value<bool>(showHelp)->default_value("false"))
+         cxxopts::value<bool>(showHelp)->default_value("false")->implicit_value("true"))
 
         ("m,cl-tuned-parameters-mode",
          "If 'UseTunedParameters' (the default), will read CL tuned parameters from the file specified by "
@@ -131,10 +160,6 @@ DriverOptions::DriverOptions(int argc, char** argv)
         "If non-empty, the given file will be used to load/save MLGO CL tuned parameters. ",
         cxxopts::value<std::string>(m_ClMLGOTunedParametersFile)->default_value(""))
 
-        ("n,service-name",
-         "If non-empty, the driver service name to be registered",
-         cxxopts::value<std::string>(m_ServiceName)->default_value("armnn_sl"))
-
         ("o,cl-tuning-level",
          "exhaustive: all lws values are tested "
          "normal: reduced number of lws values but enough to still have the performance really close to the "
@@ -173,19 +198,11 @@ DriverOptions::DriverOptions(int argc, char** argv)
          cxxopts::value<std::string>(unsupportedOperationsAsString)->default_value(""))
 
         ("v,verbose-logging", "Turns verbose logging on",
-         cxxopts::value<bool>(m_VerboseLogging)->default_value("false"))
+         cxxopts::value<bool>(m_VerboseLogging)->default_value("false")->implicit_value("true"))
 
         ("V,version", "Show version information",
-         cxxopts::value<bool>(showVersion)->default_value("false"))
-
-        ("A,asyncModelExecution", "Enable AsynModel Execution",
-         cxxopts::value<bool>(m_EnableAsyncModelExecution)->default_value("false"))
-
-        ("T,armnn-threads",
-         "Assign the number of threads used by ArmNN. "
-         "Input value must be at least 1. "
-         "Default is set to 1.",
-         cxxopts::value<unsigned int>(m_ArmnnNumberOfThreads)->default_value("1"));
+         cxxopts::value<bool>(showVersion)->default_value("false")->implicit_value("true"))
+        ;
     }
     catch (const std::exception& e)
     {
diff --git a/shim/sl/canonical/DriverOptions.hpp b/shim/sl/canonical/DriverOptions.hpp
index 6b42f4ecca..4c6b385a48 100644
--- a/shim/sl/canonical/DriverOptions.hpp
+++ b/shim/sl/canonical/DriverOptions.hpp
@@ -19,7 +19,7 @@ class DriverOptions
 public:
     DriverOptions(armnn::Compute computeDevice, bool fp16Enabled = false);
     DriverOptions(const std::vector<armnn::BackendId>& backends, bool fp16Enabled = false);
-    DriverOptions(int argc, char** argv);
+    DriverOptions();
     DriverOptions(DriverOptions&& other) = default;
 
 
diff --git a/shim/sl/support_library_service.cpp b/shim/sl/support_library_service.cpp
index 6b8167aeaa..14556fd573 100644
--- a/shim/sl/support_library_service.cpp
+++ b/shim/sl/support_library_service.cpp
@@ -12,8 +12,7 @@ namespace android::nn
 
 std::vector<SharedDevice> getDevices()
 {
-    std::vector<armnn::BackendId> backends = { armnn::Compute::CpuAcc, armnn::Compute::CpuRef, armnn::Compute::GpuAcc };
-    return { std::make_shared<armnn_driver::ArmnnDriver>(DriverOptions(backends)) };
+    return { std::make_shared<armnn_driver::ArmnnDriver>(DriverOptions()) };
 }
 
-}  // namespace android::nn
\ No newline at end of file
+}  // namespace android::nn