First version of typr propagation in the new IR.

pkg/compiler/lib/src/js_backend/codegen/task.dart

Index: pkg/compiler/lib/src/js_backend/codegen/task.dart
diff --git a/pkg/compiler/lib/src/js_backend/codegen/task.dart b/pkg/compiler/lib/src/js_backend/codegen/task.dart
index 68e1d5bfbc8476dbfefdb4e75e779a0bb09826b0..8fc5804447fff39ea8186b5f55bbc199c549af3b 100644
--- a/pkg/compiler/lib/src/js_backend/codegen/task.dart
+++ b/pkg/compiler/lib/src/js_backend/codegen/task.dart
@@ -16,6 +16,7 @@ import '../../cps_ir/cps_ir_nodes.dart' as cps;
 import '../../cps_ir/cps_ir_builder.dart';
 import '../../tree_ir/tree_ir_nodes.dart' as tree_ir;
 import '../../tree/tree.dart' as ast;
+import '../../types/types.dart' show TypeMask;
 import '../../scanner/scannerlib.dart' as scanner;
 import '../../elements/elements.dart';
 import '../../closure.dart';
@@ -28,6 +29,7 @@ import '../../tracer.dart';
 import '../../js_backend/codegen/codegen.dart';
 import '../../ssa/ssa.dart' as ssa;
 import '../../tree_ir/optimization/optimization.dart';
+import '../../cps_ir/cps_ir_nodes_sexpr.dart';
 
 class CspFunctionCompiler implements FunctionCompiler {
   final IrBuilderTask irBuilderTask;
@@ -35,6 +37,8 @@ class CspFunctionCompiler implements FunctionCompiler {
   final Compiler compiler;
   final Glue glue;
 
+  TypeSystem types;
+
   // TODO(karlklose,sigurm): remove and update dart-doc of [compile].
   final FunctionCompiler fallbackCompiler;
 
@@ -55,6 +59,7 @@ class CspFunctionCompiler implements FunctionCompiler {
   /// features not implemented it will fall back to the ssa pipeline (for
   /// platform code) or will cancel compilation (for user code).
   js.Fun compile(CodegenWorkItem work) {
+    types = new TypeMaskSystem(compiler);
     AstElement element = work.element;
     return compiler.withCurrentElement(element, () {
       try {
@@ -107,12 +112,27 @@ class CspFunctionCompiler implements FunctionCompiler {
     return cpsNode;
   }
 
+  static const Pattern PRINT_TYPED_IR_FILTER = null;
+
   cps.FunctionDefinition optimizeCpsIR(cps.FunctionDefinition cpsNode) {
     // Transformations on the CPS IR.
     traceGraph("IR Builder", cpsNode);
-    new ConstantPropagator(compiler, constantSystem)
-        .rewrite(cpsNode);
+
+    TypePropagator typePropagator = new TypePropagator<TypeMask>(compiler,
+        constantSystem, new TypeMaskSystem(compiler), compiler.internalError);
+    typePropagator.rewrite(cpsNode);
     traceGraph("Sparse constant propagation", cpsNode);
+
+    if (PRINT_TYPED_IR_FILTER != null &&
+        PRINT_TYPED_IR_FILTER.matchAsPrefix(cpsNode.element.name) != null) {
+      String printType(cps.Node node, String s) {
+        var type = typePropagator.getType(node);
+        return type == null ? s : "<$type: $s>";
+      }
+      DEBUG_MODE = true;
+      print(new SExpressionStringifier(printType).visit(cpsNode));
+    }
+
     new RedundantPhiEliminator().rewrite(cpsNode);
     traceGraph("Redundant phi elimination", cpsNode);
     new ShrinkingReducer().rewrite(cpsNode);