Implement literal maps.

dart/frog/leg/ssa/builder.dart

Index: dart/frog/leg/ssa/builder.dart
diff --git a/dart/frog/leg/ssa/builder.dart b/dart/frog/leg/ssa/builder.dart
index 9db538b274b2a99adeeb0344025f2d09cbd55fff..cd79469ea602e2ed3a07858a01935bec4ac5753a 100644
--- a/dart/frog/leg/ssa/builder.dart
+++ b/dart/frog/leg/ssa/builder.dart
@@ -93,6 +93,10 @@ class Interceptors {
   Element getExceptionUnwrapper() {
     return compiler.findHelper(const SourceString('unwrapException'));
   }
+
+  Element getMapMaker() {
+    return compiler.findHelper(const SourceString('makeLiteralMap'));
+  }
 }
 
 class SsaBuilderTask extends CompilerTask {
@@ -2236,11 +2240,25 @@ class SsaBuilder implements Visitor {
   }
 
   visitLiteralMap(LiteralMap node) {
-    generateUnimplemented('literal map not implemented', isExpression: true);
+    List<HInstruction> inputs = <HInstruction>[];
+    for (Link<Node> link = node.entries.nodes;
+         !link.isEmpty();
+         link = link.tail) {
+      visit(link.head);
+      inputs.addLast(pop());
+      inputs.addLast(pop());
+    }
+    HLiteralList keyValuePairs = new HLiteralList(inputs, node.isConst());
+    HStatic mapMaker = new HStatic(interceptors.getMapMaker());
+    add(keyValuePairs);
+    add(mapMaker);
+    inputs = <HInstruction>[mapMaker, keyValuePairs];
+    push(new HInvokeStatic(Selector.INVOCATION_1, inputs));
   }
 
   visitLiteralMapEntry(LiteralMapEntry node) {
-    compiler.unimplemented('SsaBuilder.visitLiteralMapEntry', node: node);
+    visit(node.value);
+    visit(node.key);
   }
 
   visitNamedArgument(NamedArgument node) {