[SYCL] Fix platform selection in opencl-aot (#1510)

Before picking a matched platform name, ensure the device type also
matches. This fixes a mismatch issue that was caused by an identical
supported platform name for CPU and GPU.

Only iterate through available platforms. When the error message is
non-empty, always return CLErr, so that the message is shown.

Signed-off-by: Dmitri Mokhov <[email protected]>

Author: dnmokhov

opencl-aot/include/utils.h

@@ -36,7 +36,8 @@ enum Errors : int8_t {
   OPENCL_AOT_OPTIONS_COEXISTENCE_FAILURE,
   OPENCL_AOT_TARGET_CPU_ARCH_FAILURE,
   OPENCL_AOT_DEVICE_ID_IS_EMPTY,
-  OPENCL_AOT_PROGRAM_IS_EMPTY
+  OPENCL_AOT_PROGRAM_IS_EMPTY,
+  OPENCL_AOT_PLATFORM_NOT_FOUND
 };
 
 inline bool clFailed(cl_int ReturnCode) { return CL_SUCCESS != ReturnCode; }

opencl-aot/source/utils.cpp

@@ -178,18 +178,24 @@ getOpenCLPlatform(DeviceType Type) {
   cl_int CLErr(CL_SUCCESS);
   std::string PlatformName;
 
-  const cl_uint MaxPlatformsCount = 10;
-  std::array<cl_platform_id, MaxPlatformsCount> Platforms{};
-
   cl_uint PlatformsCount = 0;
-  CLErr =
-      clGetPlatformIDs(MaxPlatformsCount, Platforms.data(), &PlatformsCount);
+  CLErr = clGetPlatformIDs(0, nullptr, &PlatformsCount);
+  if (clFailed(CLErr)) {
+    return std::make_tuple(
+        nullptr, "",
+        formatCLError("Failed to retrieve OpenCL platform count", CLErr),
+        CLErr);
+  }
+
+  std::vector<cl_platform_id> Platforms(PlatformsCount);
+  CLErr = clGetPlatformIDs(PlatformsCount, Platforms.data(), nullptr);
   if (clFailed(CLErr)) {
     return std::make_tuple(
         nullptr, "",
         formatCLError("Failed to retrieve OpenCL platform IDs", CLErr), CLErr);
   }
 
+  std::string ErrorMessage;
   for (const auto &Platform : Platforms) {
     size_t PlatformNameLength = 0;
     CLErr = clGetPlatformInfo(Platform, CL_PLATFORM_NAME, 0, nullptr,
@@ -221,24 +227,36 @@ getOpenCLPlatform(DeviceType Type) {
         std::find(SupportedPlatformNames.begin(), SupportedPlatformNames.end(),
                   PlatformNameOnLoopIteration);
     if (Result != SupportedPlatformNames.end()) {
-      PlatformId = Platform;
-      PlatformName = PlatformNameOnLoopIteration;
-      break;
+      tie(std::ignore, ErrorMessage, CLErr) = getOpenCLDevice(Platform, Type);
+      if (!clFailed(CLErr)) {
+        PlatformId = Platform;
+        PlatformName = PlatformNameOnLoopIteration;
+        break;
+      }
     }
   }
 
-  std::string ErrorMessage;
-  if (PlatformId == nullptr) {
-    ErrorMessage += "OpenCL platform ID is empty\n";
-  }
-  if (PlatformName.empty()) {
-    ErrorMessage += "OpenCL platform name is empty\n";
+  std::string SupportedPlatforms;
+  for (const auto &Platform : DeviceTypesToSupportedPlatformNames[Type]) {
+    SupportedPlatforms += "  " + Platform + '\n';
   }
-  if (!ErrorMessage.empty()) {
-    ErrorMessage += "Failed to find any of these OpenCL platforms:\n";
-    for (const auto &SupportedPlatformName :
-         DeviceTypesToSupportedPlatformNames[Type]) {
-      ErrorMessage += "  " + SupportedPlatformName + '\n';
+  if (clFailed(CLErr)) {
+    std::map<DeviceType, std::string> DeviceTypeToDeviceTypeName{
+        {cpu, "CPU"}, {gpu, "GPU"}, {fpga_fast_emu, "FPGA Fast Emu"}};
+    ErrorMessage += "Failed to find OpenCL " +
+                    DeviceTypeToDeviceTypeName[Type] +
+                    " device in these OpenCL platforms:\n" + SupportedPlatforms;
+  } else {
+    if (PlatformId == nullptr) {
+      ErrorMessage += "OpenCL platform ID is empty\n";
+    }
+    if (PlatformName.empty()) {
+      ErrorMessage += "OpenCL platform name is empty\n";
+    }
+    if (!ErrorMessage.empty()) {
+      ErrorMessage += "Failed to find any of these OpenCL platforms:\n" +
+                      SupportedPlatforms;
+      CLErr = OPENCL_AOT_PLATFORM_NOT_FOUND;
     }
   }