Isolate drgn_type to CodeGenV1

Author: ttreyer

oi/Features.cpp

@@ -36,6 +36,8 @@ std::optional<std::string_view> featureHelp(Feature f) {
       return "Generate statistics on padding of structures.";
     case Feature::CaptureThriftIsset:
       return "Capture isset data for Thrift object.";
+    case Feature::LLDB:
+      return "Use LLDB (instead of drgn) to parse the debug info.";
     case Feature::TypeGraph:
       return "Use Type Graph for code generation (CodeGen v2).";
     case Feature::PruneTypeGraph:
@@ -60,6 +62,9 @@ std::optional<std::string_view> featureHelp(Feature f) {
 
 std::span<const Feature> requirements(Feature f) {
   switch (f) {
+    case Feature::LLDB:
+      static constexpr std::array lldb = {Feature::TypeGraph};
+      return lldb;
     case Feature::TreeBuilderV2:
       static constexpr std::array tb2 = {Feature::TypeGraph};
       return tb2;

oi/Features.h

@@ -27,6 +27,7 @@
   X(PackStructs, "pack-structs")                \
   X(GenPaddingStats, "gen-padding-stats")       \
   X(CaptureThriftIsset, "capture-thrift-isset") \
+  X(LLDB, "lldb")                               \
   X(TypeGraph, "type-graph")                    \
   X(PruneTypeGraph, "prune-type-graph")         \
   X(Library, "library")                         \

oi/OIDebugger.cpp

@@ -2962,17 +2962,24 @@ bool OIDebugger::processTargetData() {
 }
 
 std::optional<std::string> OIDebugger::generateCode(const irequest& req) {
-  auto root = symbols->getRootType(req);
-  if (!root.has_value()) {
-    return std::nullopt;
-  }
 
   std::string code(headers::oi_OITraceCode_cpp);
 
   if (generatorConfig.features[Feature::TypeGraph]) {
     // CodeGen v2
+    std::string rootVariableName;
     CodeGen codegen2{generatorConfig, *symbols};
-    codegen2.codegenFromDrgn(root->type.type, code);
+    if (generatorConfig.features[Feature::LLDB]) {
+      throw std::runtime_error{"LLDB is not implemented yet"};
+    } else {
+      auto root = symbols->getDrgnRootType(req);
+      if (!root.has_value()) {
+        return std::nullopt;
+      }
+
+      rootVariableName = std::move(root->varName);
+      codegen2.codegenFromDrgn(root->type.type, code);
+    }
 
     TypeHierarchy th;
     // Make this static as a big hack to extend the fake drgn_types' lifetimes
@@ -2981,10 +2988,15 @@ std::optional<std::string> OIDebugger::generateCode(const irequest& req) {
     drgn_type* rootType;
     codegen2.exportDrgnTypes(th, drgnTypes, &rootType);
 
-    typeInfos[req] = {RootInfo{root->varName, {rootType, drgn_qualifiers{}}},
+    typeInfos[req] = {RootInfo{rootVariableName, {rootType, drgn_qualifiers{}}},
                       th,
                       std::map<std::string, PaddingInfo>{}};
   } else {
+    auto root = symbols->getDrgnRootType(req);
+    if (!root.has_value()) {
+      return std::nullopt;
+    }
+
     // OICodeGen (v1)
     auto codegen = OICodeGen::buildFromConfig(generatorConfig, *symbols);
     if (!codegen) {

oi/SymbolService.cpp

@@ -804,7 +804,7 @@ std::string SymbolService::getTypeName(struct drgn_type* type) {
   return drgn_utils::typeToName(type);
 }
 
-std::optional<RootInfo> SymbolService::getRootType(const irequest& req) {
+std::optional<RootInfo> SymbolService::getDrgnRootType(const irequest& req) {
   if (req.type == "global") {
     /*
      * This is super simple as all we have to do is locate assign the

oi/SymbolService.h

@@ -54,7 +54,7 @@ class SymbolService {
   std::shared_ptr<FuncDesc> findFuncDesc(const irequest&);
   std::shared_ptr<GlobalDesc> findGlobalDesc(const std::string&);
   static std::string getTypeName(struct drgn_type*);
-  std::optional<RootInfo> getRootType(const irequest&);
+  std::optional<RootInfo> getDrgnRootType(const irequest&);
 
   static std::optional<drgn_qualified_type> findTypeOfSymbol(
       drgn_program*, const std::string& symbolName);

test/test_drgn_parser.cpp

@@ -35,7 +35,7 @@ DrgnParser DrgnParserTest::getDrgnParser(TypeGraph& typeGraph,
 
 drgn_type* DrgnParserTest::getDrgnRoot(std::string_view function) {
   irequest req{"entry", std::string{function}, "arg0"};
-  auto* drgnRoot = symbols_->getRootType(req)->type.type;
+  auto* drgnRoot = symbols_->getDrgnRootType(req)->type.type;
   return drgnRoot;
 }