2 files changed, 103 insertions, 0 deletions
diff --git a/llvm/lib/Frontend/Offloading/CMakeLists.txt b/llvm/lib/Frontend/Offloading/CMakeLists.txt
index 8e1ede9..9747dbd 100644
--- a/llvm/lib/Frontend/Offloading/CMakeLists.txt
+++ b/llvm/lib/Frontend/Offloading/CMakeLists.txt
@@ -1,6 +1,7 @@
 add_llvm_component_library(LLVMFrontendOffloading
   Utility.cpp
   OffloadWrapper.cpp
+  PropertySet.cpp
 
   ADDITIONAL_HEADER_DIRS
   ${LLVM_MAIN_INCLUDE_DIR}/llvm/Frontend
diff --git a/llvm/lib/Frontend/Offloading/PropertySet.cpp b/llvm/lib/Frontend/Offloading/PropertySet.cpp
new file mode 100644
index 0000000..a70290d
--- /dev/null
+++ b/llvm/lib/Frontend/Offloading/PropertySet.cpp
@@ -0,0 +1,102 @@
+///===- llvm/Frontend/Offloading/PropertySet.cpp --------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Frontend/Offloading/PropertySet.h"
+#include "llvm/Support/Base64.h"
+#include "llvm/Support/JSON.h"
+#include "llvm/Support/MemoryBufferRef.h"
+
+using namespace llvm;
+using namespace llvm::offloading;
+
+void llvm::offloading::writePropertiesToJSON(
+    const PropertySetRegistry &PSRegistry, raw_ostream &Out) {
+  json::OStream J(Out);
+  J.object([&] {
+    for (const auto &[CategoryName, PropSet] : PSRegistry) {
+      auto PropSetCapture = PropSet;
+      J.attributeObject(CategoryName, [&] {
+        for (const auto &[PropName, PropVal] : PropSetCapture) {
+          switch (PropVal.index()) {
+          case 0:
+            J.attribute(PropName, std::get<uint32_t>(PropVal));
+            break;
+          case 1:
+            J.attribute(PropName, encodeBase64(std::get<ByteArray>(PropVal)));
+            break;
+          default:
+            llvm_unreachable("unsupported property type");
+          }
+        }
+      });
+    }
+  });
+}
+
+// note: createStringError has an overload that takes a format string,
+// but it uses llvm::format instead of llvm::formatv, which does
+// not work with json::Value. This is a helper function to use
+// llvm::formatv with createStringError.
+template <typename... Ts> auto createStringErrorV(Ts &&...Args) {
+  return createStringError(formatv(std::forward<Ts>(Args)...));
+}
+
+Expected<PropertyValue>
+readPropertyValueFromJSON(const json::Value &PropValueVal) {
+  if (std::optional<uint64_t> Val = PropValueVal.getAsUINT64())
+    return PropertyValue(static_cast<uint32_t>(*Val));
+
+  if (std::optional<StringRef> Val = PropValueVal.getAsString()) {
+    std::vector<char> Decoded;
+    if (Error E = decodeBase64(*Val, Decoded))
+      return createStringErrorV("unable to base64 decode the string {0}: {1}",
+                                Val, toString(std::move(E)));
+    return PropertyValue(ByteArray(Decoded.begin(), Decoded.end()));
+  }
+
+  return createStringErrorV("expected a uint64 or a string, got {0}",
+                            PropValueVal);
+}
+
+Expected<PropertySetRegistry>
+llvm::offloading::readPropertiesFromJSON(MemoryBufferRef Buf) {
+  PropertySetRegistry Res;
+  Expected<json::Value> V = json::parse(Buf.getBuffer());
+  if (Error E = V.takeError())
+    return E;
+
+  const json::Object *O = V->getAsObject();
+  if (!O)
+    return createStringErrorV(
+        "error while deserializing property set registry: "
+        "expected JSON object, got {0}",
+        *V);
+
+  for (const auto &[CategoryName, Value] : *O) {
+    const json::Object *PropSetVal = Value.getAsObject();
+    if (!PropSetVal)
+      return createStringErrorV("error while deserializing property set {0}: "
+                                "expected JSON array, got {1}",
+                                CategoryName.str(), Value);
+
+    PropertySet &PropSet = Res[CategoryName.str()];
+    for (const auto &[PropName, PropValueVal] : *PropSetVal) {
+      Expected<PropertyValue> Prop = readPropertyValueFromJSON(PropValueVal);
+      if (Error E = Prop.takeError())
+        return createStringErrorV(
+            "error while deserializing property {0} in property set {1}: {2}",
+            PropName.str(), CategoryName.str(), toString(std::move(E)));
+
+      auto [It, Inserted] =
+          PropSet.try_emplace(PropName.str(), std::move(*Prop));
+      assert(Inserted && "Property already exists in PropertySet");
+      (void)Inserted;
+    }
+  }
+  return Res;
+}