[wasm] asm.js - Parse and convert asm.js to wasm a function at a time.

src/parsing/parser.cc

Index: src/parsing/parser.cc
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index 0ae1fb619a70ff1aa8bf224fa5a613ec99ebcea4..2e40b202654a800bac1766ec1899532734e54ec4 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -724,13 +724,20 @@ FunctionLiteral* Parser::ParseProgram(Isolate* isolate, ParseInfo* info) {
   source = String::Flatten(source);
   FunctionLiteral* result;
 
+  int start_position = info->start_position();
+  int end_position = info->end_position();
+  if (start_position == 0 && end_position == 0) {
+    end_position = source->length();
+  }
+
   {
-    std::unique_ptr<Utf16CharacterStream> stream(ScannerStream::For(source));
+    std::unique_ptr<Utf16CharacterStream> stream(
+        ScannerStream::For(source, start_position, end_position));
     scanner_.Initialize(stream.get());
     result = DoParseProgram(info);
   }
   if (result != NULL) {
-    DCHECK_EQ(scanner_.peek_location().beg_pos, source->length());
+    DCHECK_EQ(scanner_.peek_location().beg_pos, end_position);
   }
   HandleSourceURLComments(isolate, info->script());
 
@@ -2622,16 +2629,9 @@ FunctionLiteral* Parser::ParseFunctionLiteral(
   //   FunctionExpression; even without enclosing parentheses it might be
   //   immediately invoked.
   // - The function literal shouldn't be hinted to eagerly compile.
-  // - For asm.js functions the body needs to be available when module
-  //   validation is active, because we examine the entire module at once.
-
-  // Inner functions will be parsed using a temporary Zone. After parsing, we
-  // will migrate unresolved variable into a Scope in the main Zone.
-  // TODO(marja): Refactor parsing modes: simplify this.
   bool use_temp_zone =
       allow_lazy() && function_type == FunctionLiteral::kDeclaration &&
-      eager_compile_hint != FunctionLiteral::kShouldEagerCompile &&
-      !(FLAG_validate_asm && scope()->IsAsmModule());
+      eager_compile_hint != FunctionLiteral::kShouldEagerCompile;
   bool is_lazy_inner_function =
       use_temp_zone && FLAG_lazy_inner_functions && !is_lazy_top_level_function;