[lldb] Remove ClangASTImporter from Target

Target is one of the classes responsible for vending ClangASTImporter.
Target doesn't need to know anything about ClangASTImporter, so if we
instead have ClangPersistentVariables vend it, we can preserve
existing behavior while improving layering and removing dependencies
from non-plugins to plugins.

lldb/include/lldb/Symbol/TypeSystemClang.h

@@ -26,6 +26,7 @@
 #include "llvm/ADT/APSInt.h"
 #include "llvm/ADT/SmallVector.h"
 
+#include "Plugins/ExpressionParser/Clang/ClangPersistentVariables.h"
 #include "lldb/Core/ClangForward.h"
 #include "lldb/Expression/ExpressionVariable.h"
 #include "lldb/Symbol/CompilerType.h"
@@ -1007,7 +1008,7 @@ public:
   PersistentExpressionState *GetPersistentExpressionState() override;
 private:
   lldb::TargetWP m_target_wp;
-  std::unique_ptr<PersistentExpressionState>
+  std::unique_ptr<ClangPersistentVariables>
       m_persistent_variables; // These are the persistent variables associated
                               // with this process for the expression parser
   std::unique_ptr<ClangASTSource> m_scratch_ast_source_up;

lldb/include/lldb/Target/Target.h

@@ -1056,8 +1056,6 @@ public:
                                                  const char *name,
                                                  Status &error);
 
-  lldb::ClangASTImporterSP GetClangASTImporter();
-
   // Install any files through the platform that need be to installed prior to
   // launching or attaching.
   Status Install(ProcessLaunchInfo *launch_info);
@@ -1304,7 +1302,6 @@ protected:
   typedef std::map<lldb::LanguageType, lldb::REPLSP> REPLMap;
   REPLMap m_repl_map;
 
-  lldb::ClangASTImporterSP m_ast_importer_sp;
   lldb::ClangModulesDeclVendorUP m_clang_modules_decl_vendor_up;
 
   lldb::SourceManagerUP m_source_manager_up;

lldb/source/Plugins/ExpressionParser/Clang/ASTResultSynthesizer.cpp

@@ -459,7 +459,7 @@ void ASTResultSynthesizer::CommitPersistentDecls() {
     StringRef name = decl->getName();
     ConstString name_cs(name.str().c_str());
 
-    Decl *D_scratch = m_target.GetClangASTImporter()->DeportDecl(
+    Decl *D_scratch = persistent_vars->GetClangASTImporter()->DeportDecl(
         &scratch_ctx->getASTContext(), decl);
 
     if (!D_scratch) {

lldb/source/Plugins/ExpressionParser/Clang/ClangPersistentVariables.cpp

@@ -9,6 +9,7 @@
 #include "ClangPersistentVariables.h"
 
 #include "lldb/Core/Value.h"
+#include "lldb/Symbol/ClangASTImporter.h"
 #include "lldb/Symbol/TypeSystemClang.h"
 #include "lldb/Target/Target.h"
 #include "lldb/Utility/DataExtractor.h"
@@ -99,3 +100,10 @@ clang::NamedDecl *
 ClangPersistentVariables::GetPersistentDecl(ConstString name) {
   return m_persistent_decls.lookup(name.GetCString()).m_decl;
 }
+
+lldb::ClangASTImporterSP ClangPersistentVariables::GetClangASTImporter() {
+  if (!m_ast_importer_sp) {
+    m_ast_importer_sp = std::make_shared<ClangASTImporter>();
+  }
+  return m_ast_importer_sp;
+}

lldb/source/Plugins/ExpressionParser/Clang/ClangPersistentVariables.h

@@ -36,6 +36,8 @@ public:
     return pv->getKind() == PersistentExpressionState::eKindClang;
   }
 
+  lldb::ClangASTImporterSP GetClangASTImporter();
+
   lldb::ExpressionVariableSP
   CreatePersistentVariable(const lldb::ValueObjectSP &valobj_sp) override;
 
@@ -96,6 +98,7 @@ private:
       m_hand_loaded_clang_modules; ///< These are Clang modules we hand-loaded;
                                    ///these are the highest-
                                    ///< priority source for macros.
+  lldb::ClangASTImporterSP m_ast_importer_sp;
 };
 
 } // namespace lldb_private

lldb/source/Plugins/ExpressionParser/Clang/ClangUserExpression.cpp

@@ -896,9 +896,16 @@ void ClangUserExpression::ClangUserExpressionHelper::ResetDeclMap(
     Materializer::PersistentVariableDelegate &delegate,
     bool keep_result_in_memory,
     ValueObject *ctx_obj) {
-  m_expr_decl_map_up.reset(new ClangExpressionDeclMap(
-      keep_result_in_memory, &delegate, exe_ctx.GetTargetSP(),
-      exe_ctx.GetTargetRef().GetClangASTImporter(), ctx_obj));
+  lldb::ClangASTImporterSP ast_importer;
+  auto *state = exe_ctx.GetTargetSP()->GetPersistentExpressionStateForLanguage(
+      lldb::eLanguageTypeC);
+  if (state) {
+    auto *persistent_vars = llvm::cast<ClangPersistentVariables>(state);
+    ast_importer = persistent_vars->GetClangASTImporter();
+  }
+  m_expr_decl_map_up.reset(
+      new ClangExpressionDeclMap(keep_result_in_memory, &delegate,
+                                 exe_ctx.GetTargetSP(), ast_importer, ctx_obj));
 }
 
 clang::ASTConsumer *

lldb/source/Plugins/ExpressionParser/Clang/ClangUtilityFunction.cpp

@@ -12,6 +12,7 @@
 #include "ClangExpressionDeclMap.h"
 #include "ClangExpressionParser.h"
 #include "ClangExpressionSourceCode.h"
+#include "ClangPersistentVariables.h"
 
 #include <stdio.h>
 #if HAVE_SYS_TYPES_H
@@ -159,7 +160,14 @@ bool ClangUtilityFunction::Install(DiagnosticManager &diagnostic_manager,
 
 void ClangUtilityFunction::ClangUtilityFunctionHelper::ResetDeclMap(
     ExecutionContext &exe_ctx, bool keep_result_in_memory) {
-  m_expr_decl_map_up.reset(new ClangExpressionDeclMap(
-      keep_result_in_memory, nullptr, exe_ctx.GetTargetSP(),
-      exe_ctx.GetTargetRef().GetClangASTImporter(), nullptr));
+  lldb::ClangASTImporterSP ast_importer;
+  auto *state = exe_ctx.GetTargetSP()->GetPersistentExpressionStateForLanguage(
+      lldb::eLanguageTypeC);
+  if (state) {
+    auto *persistent_vars = llvm::cast<ClangPersistentVariables>(state);
+    ast_importer = persistent_vars->GetClangASTImporter();
+  }
+  m_expr_decl_map_up.reset(
+      new ClangExpressionDeclMap(keep_result_in_memory, nullptr,
+                                 exe_ctx.GetTargetSP(), ast_importer, nullptr));
 }

lldb/source/Plugins/Language/CPlusPlus/BlockPointer.cpp

@@ -8,14 +8,14 @@
 
 #include "BlockPointer.h"
 
+#include "Plugins/ExpressionParser/Clang/ClangPersistentVariables.h"
 #include "lldb/Core/ValueObject.h"
 #include "lldb/DataFormatters/FormattersHelpers.h"
-#include "lldb/Symbol/TypeSystemClang.h"
 #include "lldb/Symbol/ClangASTImporter.h"
 #include "lldb/Symbol/CompilerType.h"
 #include "lldb/Symbol/TypeSystem.h"
+#include "lldb/Symbol/TypeSystemClang.h"
 #include "lldb/Target/Target.h"
-
 #include "lldb/Utility/LLDBAssert.h"
 #include "lldb/Utility/Log.h"
 
@@ -56,7 +56,13 @@ public:
       return;
     }
 
-    ClangASTImporterSP clang_ast_importer = target_sp->GetClangASTImporter();
+    lldb::ClangASTImporterSP clang_ast_importer;
+    auto *state = target_sp->GetPersistentExpressionStateForLanguage(
+        lldb::eLanguageTypeC_plus_plus);
+    if (state) {
+      auto *persistent_vars = llvm::cast<ClangPersistentVariables>(state);
+      clang_ast_importer = persistent_vars->GetClangASTImporter();
+    }
 
     if (!clang_ast_importer) {
       return;

lldb/source/Symbol/TypeSystemClang.cpp

@@ -9262,7 +9262,7 @@ TypeSystemClangForExpressions::TypeSystemClangForExpressions(
       m_target_wp(target.shared_from_this()),
       m_persistent_variables(new ClangPersistentVariables) {
   m_scratch_ast_source_up.reset(new ClangASTSource(
-      target.shared_from_this(), target.GetClangASTImporter()));
+      target.shared_from_this(), m_persistent_variables->GetClangASTImporter()));
   m_scratch_ast_source_up->InstallASTContext(*this);
   llvm::IntrusiveRefCntPtr<clang::ExternalASTSource> proxy_ast_source(
       m_scratch_ast_source_up->CreateProxy());

lldb/source/Target/Target.cpp

@@ -37,7 +37,6 @@
 #include "lldb/Interpreter/OptionGroupWatchpoint.h"
 #include "lldb/Interpreter/OptionValues.h"
 #include "lldb/Interpreter/Property.h"
-#include "lldb/Symbol/ClangASTImporter.h"
 #include "lldb/Symbol/Function.h"
 #include "lldb/Symbol/ObjectFile.h"
 #include "lldb/Symbol/Symbol.h"
@@ -91,7 +90,7 @@ Target::Target(Debugger &debugger, const ArchSpec &target_arch,
       m_mutex(), m_arch(target_arch), m_images(this), m_section_load_history(),
       m_breakpoint_list(false), m_internal_breakpoint_list(true),
       m_watchpoint_list(), m_process_sp(), m_search_filter_sp(),
-      m_image_search_paths(ImageSearchPathsChanged, this), m_ast_importer_sp(),
+      m_image_search_paths(ImageSearchPathsChanged, this),
       m_source_manager_up(), m_stop_hooks(), m_stop_hook_next_id(0),
       m_valid(true), m_suppress_stop_hooks(false),
       m_is_dummy_target(is_dummy_target),
@@ -1378,7 +1377,6 @@ void Target::ClearModules(bool delete_locations) {
   m_section_load_history.Clear();
   m_images.Clear();
   m_scratch_type_system_map.Clear();
-  m_ast_importer_sp.reset();
 }
 
 void Target::DidExec() {
@@ -2258,16 +2256,6 @@ Target::GetUtilityFunctionForLanguage(const char *text,
   return utility_fn;
 }
 
-ClangASTImporterSP Target::GetClangASTImporter() {
-  if (m_valid) {
-    if (!m_ast_importer_sp) {
-      m_ast_importer_sp = std::make_shared<ClangASTImporter>();
-    }
-    return m_ast_importer_sp;
-  }
-  return ClangASTImporterSP();
-}
-
 void Target::SettingsInitialize() { Process::SettingsInitialize(); }
 
 void Target::SettingsTerminate() { Process::SettingsTerminate(); }