treewide: use C++ exceptions properly

Since the codebase is designed around proper C++ idioms such as RAII, it
makes sense to only use C++ exceptions internally instead of mixing
exceptions and error codes. The exceptions are now caught at top level
to preserve compatibility with the existing error code-based API.

Note that we deliberately do not catch C++ runtime errors (such as
`std::bad_alloc`) nor logic errors (aka failed assertions) because no
actual handling can ever happen for such errors.

However, in the C interface we do catch _all_ exceptions (...) and
convert them into a wild-card error code.

1 files changed, 14 insertions, 13 deletions

diff --git a/src/routines/common.cpp b/src/routines/common.cpp
index 3969cf9f..c995dc12 100644
--- a/src/routines/common.cpp
+++ b/src/routines/common.cpp
@@ -20,22 +20,26 @@ namespace clblast {
 // =================================================================================================
 
 // Enqueues a kernel, waits for completion, and checks for errors
-StatusCode RunKernel(Kernel &kernel, Queue &queue, const Device &device,
-                     std::vector<size_t> global, const std::vector<size_t> &local,
-                     EventPointer event, const std::vector<Event> &waitForEvents) {
+void RunKernel(Kernel &kernel, Queue &queue, const Device &device,
+               std::vector<size_t> global, const std::vector<size_t> &local,
+               EventPointer event, const std::vector<Event> &waitForEvents) {
 
   if (!local.empty()) {
     // Tests for validity of the local thread sizes
     if (local.size() > device.MaxWorkItemDimensions()) {
-      return StatusCode::kInvalidLocalNumDimensions;
+      throw RuntimeErrorCode(StatusCode::kInvalidLocalNumDimensions);
     }
     const auto max_work_item_sizes = device.MaxWorkItemSizes();
     for (auto i=size_t{0}; i<local.size(); ++i) {
-      if (local[i] > max_work_item_sizes[i]) { return StatusCode::kInvalidLocalThreadsDim; }
+      if (local[i] > max_work_item_sizes[i]) {
+        throw RuntimeErrorCode(StatusCode::kInvalidLocalThreadsDim);
+      }
     }
     auto local_size = size_t{1};
     for (auto &item: local) { local_size *= item; }
-    if (local_size > device.MaxWorkGroupSize()) { return StatusCode::kInvalidLocalThreadsTotal; }
+    if (local_size > device.MaxWorkGroupSize()) {
+      throw RuntimeErrorCode(StatusCode::kInvalidLocalThreadsTotal);
+    }
 
     // Make sure the global thread sizes are at least equal to the local sizes
     for (auto i=size_t{0}; i<global.size(); ++i) {
@@ -45,7 +49,9 @@ StatusCode RunKernel(Kernel &kernel, Queue &queue, const Device &device,
 
   // Tests for local memory usage
   const auto local_mem_usage = kernel.LocalMemUsage(device);
-  if (!device.IsLocalMemoryValid(local_mem_usage)) { return StatusCode::kInvalidLocalMemUsage; }
+  if (!device.IsLocalMemoryValid(local_mem_usage)) {
+    throw RuntimeErrorCode(StatusCode::kInvalidLocalMemUsage);
+  }
 
   // Prints the name of the kernel to launch in case of debugging in verbose mode
   #ifdef VERBOSE
@@ -55,9 +61,7 @@ StatusCode RunKernel(Kernel &kernel, Queue &queue, const Device &device,
   #endif
 
   // Launches the kernel (and checks for launch errors)
-  try {
-    kernel.Launch(queue, global, local, event, waitForEvents);
-  } catch (...) { return StatusCode::kKernelLaunchError; }
+  kernel.Launch(queue, global, local, event, waitForEvents);
 
   // Prints the elapsed execution time in case of debugging in verbose mode
   #ifdef VERBOSE
@@ -66,9 +70,6 @@ StatusCode RunKernel(Kernel &kernel, Queue &queue, const Device &device,
     const auto timing = std::chrono::duration<double,std::milli>(elapsed_time).count();
     printf("[DEBUG] Completed kernel in %.2lf ms\n", timing);
   #endif
-
-  // No errors, normal termination of this function
-  return StatusCode::kSuccess;
 }
 
 // =================================================================================================