[clang] [ssaf][UnsafeBufferUsage] Add JSON serialization for UnsafeBufferUsage (PR #187156)

[Balázs Benics via cfe-commits]

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@@ -0,0 +1,88 @@
+//===---------- UnsafeBufferUsage.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 "clang/ScalableStaticAnalysisFramework/Analyses/UnsafeBufferUsage/UnsafeBufferUsage.h"
+#include "clang/ScalableStaticAnalysisFramework/SSAFForceLinker.h" // IWYU pragma: keep
+#include "llvm/Support/Error.h"
+
+namespace {
+constexpr const char *const UnsafeBuffersKey = "UnsafeBuffers";
+} // namespace
+
+namespace clang::ssaf {
+using Object = llvm::json::Object;
+using Array = llvm::json::Array;
+
+llvm::json::Object UnsafeBufferUsageEntitySummary::jsonSerializeFn(
+    const EntitySummary &ES, JSONFormat::EntityIdToJSONFn EntityIdToJSON) {
+  // Writes a EntityPointerLevel as
+  // Array {
+  //   Object {
+  //     "@" : [entity-id]
+  //   },
+  //   [pointer-level]
+  // }
+  Array UnsafeBuffersData;
+
+  for (const auto &EPL :
+       static_cast<const UnsafeBufferUsageEntitySummary &>(ES).UnsafeBuffers)
+    UnsafeBuffersData.push_back(Array{// EntityId:
+                                      EntityIdToJSON(EPL.getEntity()),
+                                      // PointerLevel:
+                                      EPL.getPointerLevel()});
+
+  Object Data;
+
+  Data[UnsafeBuffersKey] = std::move(UnsafeBuffersData);
+  return Data;
+}
+
+llvm::Expected<std::unique_ptr<EntitySummary>>
+UnsafeBufferUsageEntitySummary::jsonDeserializeFn(
+    const llvm::json::Object &Data, EntityIdTable &,
+    JSONFormat::EntityIdFromJSONFn EntityIdFromJSON) {
+  const Array *UnsafeBuffersData = Data.getArray(UnsafeBuffersKey);
+
+  if (!UnsafeBuffersData)
+    return llvm::createStringError("expected a json::Object with a key %s",
+                                   UnsafeBuffersKey);
+
+  EntityPointerLevelSet EPLs;
+
+  for (auto &EltData : *UnsafeBuffersData) {
+    const Array *EltDataAsArr = EltData.getAsArray();
+
+    if (!EltDataAsArr || EltDataAsArr->size() != 2)
+      return llvm::createStringError("expected a json::Array of size 2");
+
+    const Object *IdData = (*EltDataAsArr)[0].getAsObject();
+    std::optional<uint64_t> PtrLvData = (*EltDataAsArr)[1].getAsInteger();
+
+    if (!IdData || !PtrLvData)
+      return llvm::createStringError("expected a json::Value of integer type");
+
+    llvm::Expected<EntityId> Id = EntityIdFromJSON(*IdData);
+
+    if (!Id)
+      return Id.takeError();
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steakhal wrote:

Same goes here. We propagate an error, but lose the context from where.
I think these could be addressed by using the ErrorBuilder.

https://github.com/llvm/llvm-project/pull/187156