Mark await expressions as caught or uncaught

src/parsing/parser.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/parsing/parser.h"
 
 #include <memory>
 
 #include "src/api.h"
 #include "src/ast/ast-expression-rewriter.h"
@@ skipping 3807 matching lines @@
       catch_scope->DeclareLocal(ast_value_factory()->dot_catch_string(), VAR,
                                 kCreatedInitialized, NORMAL_VARIABLE);
   Block* catch_block = factory()->NewBlock(nullptr, 1, true, kNoSourcePosition);
 
   Expression* promise_reject = BuildRejectPromise(
       factory()->NewVariableProxy(catch_variable), kNoSourcePosition);
   ReturnStatement* return_promise_reject =
       factory()->NewReturnStatement(promise_reject, kNoSourcePosition);
   catch_block->statements()->Add(return_promise_reject, zone());
 
-  TryStatement* try_catch_statement = factory()->NewTryCatchStatement(
-      inner_block, catch_scope, catch_variable, catch_block, kNoSourcePosition);
+  TryStatement* try_catch_statement =
+      factory()->NewTryCatchStatementForAsyncAwait(inner_block, catch_scope,
+                                                   catch_variable, catch_block,
+                                                   kNoSourcePosition);
 
   // There is no TryCatchFinally node, so wrap it in an outer try/finally
   Block* outer_try_block =
       factory()->NewBlock(nullptr, 1, true, kNoSourcePosition);
   outer_try_block->statements()->Add(try_catch_statement, zone());
 
   // finally { if (.debug_is_active) %DebugPopPromise(); }
   Block* finally_block =
       factory()->NewBlock(nullptr, 1, true, kNoSourcePosition);
   {
@@ skipping 915 matching lines @@
   do_block->statements()->Add(
       factory()->NewExpressionStatement(value_assignment, value->position()),
       zone());
 
   ZoneList<Expression*>* async_function_await_args =
       new (zone()) ZoneList<Expression*>(2, zone());
   Expression* generator_object =
       factory()->NewVariableProxy(generator_object_variable);
   async_function_await_args->Add(generator_object, zone());
   async_function_await_args->Add(factory()->NewVariableProxy(temp_var), zone());
-  Expression* async_function_await = factory()->NewCallRuntime(
-      Context::ASYNC_FUNCTION_AWAIT_INDEX, async_function_await_args, nopos);
+
+  // The parser emits calls to AsyncFunctionAwaitCaught, but the
+  // AstNumberingVisitor will rewrite this to AsyncFunctionAwaitUncaught
+  // if there is no local enclosing try/catch block.
+  Expression* async_function_await =
+      factory()->NewCallRuntime(Context::ASYNC_FUNCTION_AWAIT_CAUGHT_INDEX,
+                                async_function_await_args, nopos);
 
   // Wrap await to provide a break location between value evaluation and yield.
   Expression* await_assignment = factory()->NewAssignment(
       Token::ASSIGN, factory()->NewVariableProxy(temp_var),
       async_function_await, nopos);
   do_block->statements()->Add(
       factory()->NewExpressionStatement(await_assignment, await_pos), zone());
   Expression* do_expr = factory()->NewDoExpression(do_block, temp_var, nopos);
 
   generator_object = factory()->NewVariableProxy(generator_object_variable);
@@ skipping 1201 matching lines @@
   node->Print(Isolate::Current());
 }
 #endif  // DEBUG
 
 #undef CHECK_OK
 #undef CHECK_OK_VOID
 #undef CHECK_FAILED
 
 }  // namespace internal
 }  // namespace v8