Associate partial source map with each code block in Universe.generatedCode.

lib/compiler/implementation/ssa/codegen.dart

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 class SsaCodeGeneratorTask extends CompilerTask {
   final JavaScriptBackend backend;
   SsaCodeGeneratorTask(JavaScriptBackend backend)
       : this.backend = backend,
         super(backend.compiler);
   String get name() => 'SSA code generator';
   NativeEmitter get nativeEmitter() => backend.emitter.nativeEmitter;
 
 
-  String buildJavaScriptFunction(FunctionElement element,
+  CodeBlock buildJavaScriptFunction(FunctionElement element,
                                  String parameters,
                                  String body) {
     String extraSpace = "";
     // Members are emitted inside a JavaScript object literal. To line up the
     // indentation we want the closing curly brace to be indented by one space.
     // Example:
     // defineClass("A", "B", ... , {
     //  foo$1: function(..) {
     //  },  /* <========== indent by 1. */
     //  bar$2: function(..) {
     //  },  /* <========== indent by 1. */
     //
     // For static functions this is not necessary:
     // $.staticFun = function() {
     //   ...
     // };
     if (element.isInstanceMember() ||
         element.kind == ElementKind.GENERATIVE_CONSTRUCTOR_BODY) {
       extraSpace = " ";
     }
-    return 'function($parameters) {\n$body$extraSpace}';
+
+    String code = 'function($parameters) {\n$body$extraSpace}';
+    List<SourceMappingEntry> sourceMappings = new List<SourceMappingEntry>();
+    SourceFile sourceFile = element.getCompilationUnit().script.file;
+    FunctionExpression expression = element.cachedNode;
+    sourceMappings.add(new SourceMappingEntry(
+      sourceFile, expression.getBeginToken().charOffset, 0));
+    sourceMappings.add(new SourceMappingEntry(
+      sourceFile, expression.getEndToken().charOffset, code.length - 1));
+    return new CodeBlock(code, sourceMappings);
   }
 
-  String generateMethod(WorkItem work, HGraph graph) {
+  CodeBlock generateMethod(WorkItem work, HGraph graph) {
     return measure(() {
       compiler.tracer.traceGraph("codegen", graph);
       Map<Element, String> parameterNames = getParameterNames(work);
       parameterNames.forEach((element, name) {
         compiler.enqueuer.codegen.addToWorkList(element);
       });
       String parameters = Strings.join(parameterNames.getValues(), ', ');
       SsaOptimizedCodeGenerator codegen = new SsaOptimizedCodeGenerator(
           backend, work, parameters, parameterNames);
       codegen.visitGraph(graph);
@@ skipping 13 matching lines @@
         native.generateMethodWithPrototypeCheckForElement(
             compiler, buffer, element, '${codegen.buffer}', parameters);
         code = buffer.toString();
       } else {
         code = codegen.buffer.toString();
       }
       return buildJavaScriptFunction(element, parameters, code);
     });
   }
 
-  String generateBailoutMethod(WorkItem work, HGraph graph) {
+  CodeBlock generateBailoutMethod(WorkItem work, HGraph graph) {
     return measure(() {
       compiler.tracer.traceGraph("codegen-bailout", graph);
 
       Map<Element, String> parameterNames = getParameterNames(work);
       String parameters = Strings.join(parameterNames.getValues(), ', ');
       SsaUnoptimizedCodeGenerator codegen = new SsaUnoptimizedCodeGenerator(
           backend, work, parameters, parameterNames);
       codegen.visitGraph(graph);
 
       String body = '${codegen.setup}${codegen.buffer}';
@@ skipping 2839 matching lines @@
       startBailoutSwitch();
     }
   }
 
   void endLabeledBlock(HLabeledBlockInformation labeledBlockInfo) {
     if (labeledBlockInfo.body.start.hasGuards()) {
       endBailoutSwitch();
     }
   }
 }
+
+class SourceMappingEntry {

[floitsch, 2012/07/02 15:18:32]

I don't think these classes belong here.
The CodeBlock should be at least at compiler level and the SourceMappingEntry
probably somewhere in the source-mapping files.

[podivilov, 2012/07/03 13:08:49]

Moved CodeBlock to universe.dart. Please let me know if there's a better place.

+  SourceFile sourceFile;
+  int sourceOffset;
+  int targetOffset;
+  String sourceName;
+
+  SourceMappingEntry(this.sourceFile,
+                     this.sourceOffset,
+                     this.targetOffset,
+                     [this.sourceName]);
+}
+
+class CodeBlock {
+  String code;
+  List<SourceMappingEntry> sourceMappings;
+  CodeBlock(this.code, this.sourceMappings);
+}