Functional JavaScript AST source position updates

sdk/lib/_internal/compiler/implementation/ssa/codegen.dart

Index: sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
diff --git a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
index 638b0b52bfeabf82458b4288955b5d65f7d5a5d0..290764580e504d8c8bae94f3bed5af191cdc4c7a 100644
--- a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
+++ b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
@@ -31,15 +31,14 @@ class SsaCodeGeneratorTask extends CompilerTask {
     }
     // TODO(podivilov): find the right sourceFile here and remove offset
     // checks below.
+    var sourcePosition, endSourcePosition;
     if (beginToken.charOffset < sourceFile.length) {
-      node.sourcePosition =
-          new TokenSourceFileLocation(sourceFile, beginToken);
+      sourcePosition = new TokenSourceFileLocation(sourceFile, beginToken);
     }
     if (endToken.charOffset < sourceFile.length) {
-      node.endSourcePosition =
-          new TokenSourceFileLocation(sourceFile, endToken);
+      endSourcePosition = new TokenSourceFileLocation(sourceFile, endToken);
     }
-    return node;
+    return node.withPosition(sourcePosition, endSourcePosition);
   }
 
   SourceFile sourceFileOfElement(Element element) {
@@ -204,7 +203,7 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
   void pushStatement(js.Statement statement, [HInstruction instruction]) {
     assert(expressionStack.isEmpty);
     if (instruction != null) {
-      attachLocation(statement, instruction);
+      statement = attachLocation(statement, instruction);
     }
     currentContainer.statements.add(statement);
   }
@@ -228,7 +227,7 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
    */
   push(js.Expression expression, [HInstruction instruction]) {
     if (instruction != null) {
-      attachLocation(expression, instruction);
+      expression = attachLocation(expression, instruction);
     }
     expressionStack.add(expression);
   }
@@ -238,20 +237,19 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
   }
 
   attachLocationToLast(HInstruction instruction) {
-    attachLocation(expressionStack.last, instruction);
+    int index = expressionStack.length - 1;
+    expressionStack[index] =
+        attachLocation(expressionStack[index], instruction);
   }
 
   js.Node attachLocation(js.Node jsNode, HInstruction instruction) {
-    jsNode.sourcePosition = instruction.sourcePosition;
-    return jsNode;
+    return jsNode.withLocation(instruction.sourcePosition);
   }
 
   js.Node attachLocationRange(js.Node jsNode,
                               SourceFileLocation sourcePosition,
                               SourceFileLocation endSourcePosition) {
-    jsNode.sourcePosition = sourcePosition;
-    jsNode.endSourcePosition = endSourcePosition;
-    return jsNode;
+    return jsNode.withPosition(sourcePosition, endSourcePosition);
   }
 
   void preGenerateMethod(HGraph graph) {
@@ -920,8 +918,8 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
         compiler.internalError(condition.conditionExpression,
             'Unexpected loop kind: ${info.kind}.');
     }
-    attachLocationRange(loop, info.sourcePosition, info.endSourcePosition);
-    js.Statement result = loop;
+    js.Statement result =
+        attachLocationRange(loop, info.sourcePosition, info.endSourcePosition);
     if (info.kind == HLoopBlockInformation.SWITCH_CONTINUE_LOOP) {
       String continueLabelString =
           backend.namer.implicitContinueLabelName(info.target);
@@ -2001,7 +1999,7 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
       arguments.add(pop());
     }
     js.Call value = new js.Call(jsHelper, arguments);
-    attachLocation(value, location);
+    value = attachLocation(value, location);
     // BUG(4906): Using throw/return here adds to the size of the generated code
     // but it has the advantage of explicitly telling the JS engine that
     // this code path will terminate abruptly. Needs more work.
@@ -2022,7 +2020,7 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
     js.VariableUse jsHelper =
         new js.VariableUse(backend.namer.isolateAccess(helper));
     js.Call value = new js.Call(jsHelper, [pop()]);
-    attachLocation(value, argument);
+    value = attachLocation(value, argument);
     push(value, node);
   }