[vm/debugger] Adds pragma support for func. decl.

This fixes issue #45710 by adding support for pragma
annotations on local functions which are lazily created
via the flow graph builder (as opposed to the kernel loader).

TEST=Added regression test to notify_debugger_on_exception_test.dart

Bug: https://github.com/dart-lang/sdk/issues/45710, https://github.com/dart-lang/sdk/issues/45987
Change-Id: I13f2f8d2b7d05ea1cb423c142537789e99a919d3
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/199420
Commit-Queue: Clement Skau <cskau@google.com>
Reviewed-by: Martin Kustermann <kustermann@google.com>

runtime/observatory/tests/service/notify_debugger_on_exception_test.dart

@@ -9,7 +9,12 @@
 import 'test_helper.dart';
 import 'service_test_common.dart';
 
-const int LINE_A = 24;
+const int LINE_A = 16;
+const int LINE_B = 32;
+
+syncThrow() {
+  throw 'Hello from syncThrow!'; // Line A.
+}
 
 @pragma('vm:notify-debugger-on-exception')
 void catchNotifyDebugger(Function() code) {
@@ -20,17 +25,30 @@ void catchNotifyDebugger(Function() code) {
   }
 }
 
-syncThrow() {
-  throw 'Hello from syncThrow!'; // Line A.
+void catchNotifyDebuggerNested() {
+  @pragma('vm:notify-debugger-on-exception')
+  void nested() {
+    try {
+      throw 'Hello from nested!'; // Line B.
+    } catch (e) {
+      // Ignore. Internals will notify debugger.
+    }
+  }
+
+  nested();
 }
 
 testMain() {
   catchNotifyDebugger(syncThrow);
+  catchNotifyDebuggerNested();
 }
 
 final tests = <IsolateTest>[
   hasStoppedWithUnhandledException,
   stoppedAtLine(LINE_A),
+  resumeIsolate,
+  hasStoppedWithUnhandledException,
+  stoppedAtLine(LINE_B),
 ];
 
 main([args = const <String>[]]) => runIsolateTests(args, tests,

runtime/observatory_2/tests/service_2/notify_debugger_on_exception_test.dart

@@ -9,7 +9,12 @@
 import 'test_helper.dart';
 import 'service_test_common.dart';
 
-const int LINE_A = 24;
+const int LINE_A = 16;
+const int LINE_B = 32;
+
+syncThrow() {
+  throw 'Hello from syncThrow!'; // Line A.
+}
 
 @pragma('vm:notify-debugger-on-exception')
 void catchNotifyDebugger(Function() code) {
@@ -20,17 +25,30 @@ void catchNotifyDebugger(Function() code) {
   }
 }
 
-syncThrow() {
-  throw 'Hello from syncThrow!'; // Line A.
+void catchNotifyDebuggerNested() {
+  @pragma('vm:notify-debugger-on-exception')
+  void nested() {
+    try {
+      throw 'Hello from nested!'; // Line B.
+    } catch (e) {
+      // Ignore. Internals will notify debugger.
+    }
+  }
+
+  nested();
 }
 
 testMain() {
   catchNotifyDebugger(syncThrow);
+  catchNotifyDebuggerNested();
 }
 
 final tests = <IsolateTest>[
   hasStoppedWithUnhandledException,
   stoppedAtLine(LINE_A),
+  resumeIsolate,
+  hasStoppedWithUnhandledException,
+  stoppedAtLine(LINE_B),
 ];
 
 main([args = const <String>[]]) => runIsolateTests(args, tests,

runtime/vm/compiler/frontend/kernel_binary_flowgraph.cc

@@ -1257,6 +1257,7 @@ Fragment StreamingFlowGraphBuilder::BuildExpression(TokenPosition* position) {
 }
 
 Fragment StreamingFlowGraphBuilder::BuildStatement() {
+  intptr_t offset = ReaderOffset();
   Tag tag = ReadTag();  // read tag.
   switch (tag) {
     case kExpressionStatement:
@@ -1300,7 +1301,7 @@ Fragment StreamingFlowGraphBuilder::BuildStatement() {
     case kVariableDeclaration:
       return BuildVariableDeclaration();
     case kFunctionDeclaration:
-      return BuildFunctionDeclaration();
+      return BuildFunctionDeclaration(offset);
     default:
       ReportUnexpectedTag("statement", tag);
       UNREACHABLE();
@@ -4241,7 +4242,9 @@ Fragment StreamingFlowGraphBuilder::BuildMapLiteral(TokenPosition* p) {
 
 Fragment StreamingFlowGraphBuilder::BuildFunctionExpression() {
   ReadPosition();  // read position.
-  return BuildFunctionNode(TokenPosition::kNoSource, StringIndex());
+  return BuildFunctionNode(TokenPosition::kNoSource, StringIndex(),
+                           /*has_valid_annotation=*/false, /*has_pragma=*/false,
+                           /*func_decl_offset=*/0);
 }
 
 Fragment StreamingFlowGraphBuilder::BuildLet(TokenPosition* p) {
@@ -5424,16 +5427,39 @@ Fragment StreamingFlowGraphBuilder::BuildVariableDeclaration() {
   return instructions;
 }
 
-Fragment StreamingFlowGraphBuilder::BuildFunctionDeclaration() {
-  TokenPosition position = ReadPosition();  // read position.
-  intptr_t variable_offset = ReaderOffset() + data_program_offset_;
+Fragment StreamingFlowGraphBuilder::BuildFunctionDeclaration(intptr_t offset) {
+  TokenPosition position = ReadPosition();
+  const intptr_t variable_offset = ReaderOffset() + data_program_offset_;
 
-  // read variable declaration.
+  // Read variable declaration.
   VariableDeclarationHelper helper(this);
+
+  bool has_pragma = false;
+  bool has_valid_annotation = false;
+  helper.ReadUntilExcluding(VariableDeclarationHelper::kAnnotations);
+  const intptr_t annotation_count = ReadListLength();
+  for (intptr_t i = 0; i < annotation_count; ++i) {
+    const intptr_t tag = PeekTag();
+    if (tag != kInvalidExpression) {
+      has_valid_annotation = true;
+    }
+    if (tag == kConstantExpression) {
+      auto& instance = Instance::Handle();
+      instance = constant_reader_.ReadConstantExpression();
+      if (instance.clazz() == IG->object_store()->pragma_class()) {
+        has_pragma = true;
+      }
+      continue;
+    }
+    SkipExpression();
+  }
+  helper.SetJustRead(VariableDeclarationHelper::kAnnotations);
+
   helper.ReadUntilExcluding(VariableDeclarationHelper::kEnd);
 
   Fragment instructions = DebugStepCheck(position);
-  instructions += BuildFunctionNode(position, helper.name_index_);
+  instructions += BuildFunctionNode(position, helper.name_index_,
+                                    has_valid_annotation, has_pragma, offset);
   instructions += StoreLocal(position, LookupVariable(variable_offset));
   instructions += Drop();
   return instructions;
@@ -5441,7 +5467,10 @@ Fragment StreamingFlowGraphBuilder::BuildFunctionDeclaration() {
 
 Fragment StreamingFlowGraphBuilder::BuildFunctionNode(
     TokenPosition parent_position,
-    StringIndex name_index) {
+    StringIndex name_index,
+    bool has_valid_annotation,
+    bool has_pragma,
+    intptr_t func_decl_offset) {
   intptr_t offset = ReaderOffset();
 
   FunctionNodeHelper function_node_helper(this);
@@ -5500,6 +5529,13 @@ Fragment StreamingFlowGraphBuilder::BuildFunctionNode(
               *name, parsed_function()->function(), position);
         }
 
+        function.set_has_pragma(has_pragma);
+        if ((FLAG_enable_mirrors && has_valid_annotation) || has_pragma) {
+          auto& lib =
+              Library::Handle(Z, Class::Handle(Z, function.Owner()).library());
+          lib.AddMetadata(function, func_decl_offset);
+        }
+
         function.set_is_debuggable(function_node_helper.dart_async_marker_ ==
                                    FunctionNodeHelper::kSync);
         switch (function_node_helper.dart_async_marker_) {

runtime/vm/compiler/frontend/kernel_binary_flowgraph.h

@@ -350,9 +350,12 @@ class StreamingFlowGraphBuilder : public KernelReaderHelper {
   Fragment BuildTryFinally();
   Fragment BuildYieldStatement();
   Fragment BuildVariableDeclaration();
-  Fragment BuildFunctionDeclaration();
+  Fragment BuildFunctionDeclaration(intptr_t offset);
   Fragment BuildFunctionNode(TokenPosition parent_position,
-                             StringIndex name_index);
+                             StringIndex name_index,
+                             bool has_valid_annotation,
+                             bool has_pragma,
+                             intptr_t func_decl_offset);
 
   // Build flow graph for '_nativeEffect'.
   Fragment BuildNativeEffect();

runtime/vm/kernel.cc

@@ -452,8 +452,16 @@ class MetadataEvaluator : public KernelReaderHelper {
       } else if (tag == kConstructor) {
         ConstructorHelper constructor_helper(this);
         constructor_helper.ReadUntilExcluding(ConstructorHelper::kAnnotations);
+      } else if (tag == kFunctionDeclaration) {
+        ReadTag();
+        ReadPosition();  // fileOffset
+        VariableDeclarationHelper variable_declaration_helper(this);
+        variable_declaration_helper.ReadUntilExcluding(
+            VariableDeclarationHelper::kAnnotations);
       } else {
-        FATAL("No support for metadata on this type of kernel node\n");
+        FATAL("No support for metadata on this type of kernel node: %" Pd32
+              "\n",
+              tag);
       }
     }