[llvm] [Offload] Add Error Codes to PluginInterface (PR #138258)

[Joseph Huber via llvm-commits]

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@@ -58,6 +58,30 @@ struct GenericKernelTy;
 struct GenericDeviceTy;
 struct RecordReplayTy;
 
+enum class ErrorCode {
+#define OFFLOAD_ERRC(Name, _, Value) Name = Value,
+#include "OffloadErrcodes.inc"
+#undef OFFLOAD_ERRC
+};
+
+class OffloadErrorCategory : public std::error_category {
+  const char *name() const noexcept override { return "Offload Error"; }
+  std::string message(int ev) const override {
+    switch (static_cast<ErrorCode>(ev)) {
+#define OFFLOAD_ERRC(Name, Desc, Value)                                        \
+  case ErrorCode::Name:                                                        \
+    return #Desc;
+#include "OffloadErrcodes.inc"
+#undef OFFLOAD_ERRC
+    }
+  }
+};
+
+inline std::error_code make_error_code(ErrorCode EC) {
+  static OffloadErrorCategory Cat{};
+  return {static_cast<int>(EC), Cat};
+}
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jhuber6 wrote:

Yeah, but shouldn't we be able to use `https://en.cppreference.com/w/cpp/error/errc/make_error_code` for the generic category? I don't think having an `offload` category helps us here since it's not used for anything. The string message is going to come from the person who created the error, so we only care about the numerical part of the error code.

https://github.com/llvm/llvm-project/pull/138258