Integrity checker for CPS and Tree IR.

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

 // Copyright (c) 2014, 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.
 
 /// Generate code using the cps-based IR pipeline.
 library code_generator_task;
 
 import 'glue.dart';
 import 'codegen.dart';
 import 'unsugar.dart';
 
 import '../js_backend.dart';
 import '../../dart2jslib.dart';
 import '../../cps_ir/cps_ir_nodes.dart' as cps;
 import '../../cps_ir/cps_ir_builder.dart';
+import '../../cps_ir/cps_ir_integrity.dart';
 import '../../tree_ir/tree_ir_nodes.dart' as tree_ir;
 import '../../types/types.dart' show TypeMask, UnionTypeMask, FlatTypeMask,
     ForwardingTypeMask;
 import '../../elements/elements.dart';
 import '../../js/js.dart' as js;
 import '../../io/source_information.dart' show StartEndSourceInformation;
 import '../../tree_ir/tree_ir_builder.dart' as tree_builder;
 import '../../dart_backend/backend_ast_emitter.dart' as backend_ast_emitter;
 import '../../cps_ir/optimizers.dart';
+import '../../cps_ir/optimizers.dart' as cps_opt;
 import '../../tracer.dart';
 import '../../js_backend/codegen/codegen.dart';
 import '../../ssa/ssa.dart' as ssa;
 import '../../tree_ir/optimization/optimization.dart';
+import '../../tree_ir/optimization/optimization.dart' as tree_opt;
+import '../../tree_ir/tree_ir_integrity.dart';
 import '../../cps_ir/cps_ir_nodes_sexpr.dart';
 import 'js_tree_builder.dart';
 
 class CpsFunctionCompiler implements FunctionCompiler {
   final ConstantSystem constantSystem;
   final Compiler compiler;
   final Glue glue;
 
   TypeSystem types;
 
@@ skipping 89 matching lines @@
         return "null";
       }
       String suffix = (type.isExact ? "" : "+") + (type.isNullable ? "?" : "!");
       return '${type.base.name}$suffix';
     } else if (type is ForwardingTypeMask) {
       return formatTypeMask(type.forwardTo);
     }
     throw 'unsupported: $type';
   }
 
+  void dumpTypedIR(cps.FunctionDefinition cpsNode,
+                   TypePropagator<TypeMask> typePropagator) {
+    if (PRINT_TYPED_IR_FILTER != null &&
+        PRINT_TYPED_IR_FILTER.matchAsPrefix(cpsNode.element.name) != null) {
+      String printType(nodeOrRef, String s) {
+        cps.Node node = nodeOrRef is cps.Reference
+            ? nodeOrRef.definition
+            : nodeOrRef;
+        var type = typePropagator.getType(node);
+        return type == null ? s : "$s:${formatTypeMask(type.type)}";
+      }
+      DEBUG_MODE = true;
+      print(new SExpressionStringifier(printType).visit(cpsNode));
+    }
+  }
+
+  static bool checkCpsIntegrity(cps.ExecutableDefinition node) {
+    new CheckCpsIntegrity().check(node);
+    return true; // So this can be used from assert().
+  }
+
   cps.FunctionDefinition optimizeCpsIR(cps.FunctionDefinition cpsNode) {
     // Transformations on the CPS IR.
+    void applyCpsPass(String name,
+                      cps_opt.Pass pass) {
+      pass.rewrite(cpsNode);
+      traceGraph(name, cpsNode);
+      assert(checkCpsIntegrity(cpsNode));
+    }
 
     TypePropagator typePropagator = new TypePropagator<TypeMask>(
         compiler.types,
         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 : "$s:${formatTypeMask(type.type)}";
-      }
-      DEBUG_MODE = true;
-      print(new SExpressionStringifier(printType).visit(cpsNode));
-    }
-
-    new RedundantPhiEliminator().rewrite(cpsNode);
-    traceGraph("Redundant phi elimination", cpsNode);
-    new ShrinkingReducer().rewrite(cpsNode);
-    traceGraph("Shrinking reductions", cpsNode);
+    applyCpsPass("Sparse constant propagation", typePropagator);
+    dumpTypedIR(cpsNode, typePropagator);
+    applyCpsPass("Redundant phi elimination", new RedundantPhiEliminator());
+    applyCpsPass("Shrinking reductions", new ShrinkingReducer());
 
     // Do not rewrite the IR after variable allocation.  Allocation
     // makes decisions based on an approximation of IR variable live
     // ranges that can be invalidated by transforming the IR.
     new cps.RegisterAllocator().visit(cpsNode);
     return cpsNode;
   }
 
   tree_ir.FunctionDefinition compileToTreeIR(cps.FunctionDefinition cpsNode) {
     tree_builder.Builder builder = new JsTreeBuilder(
         compiler.internalError, compiler.identicalFunction, glue);
     tree_ir.FunctionDefinition treeNode = builder.buildFunction(cpsNode);
     assert(treeNode != null);
     traceGraph('Tree builder', treeNode);
+    assert(checkTreeIntegrity(treeNode));
     return treeNode;
   }
 
-  tree_ir.FunctionDefinition optimizeTreeIR(
-      tree_ir.FunctionDefinition treeNode) {
-    // Transformations on the Tree IR.
-    new StatementRewriter().rewrite(treeNode);
-    traceGraph('Statement rewriter', treeNode);
-    new CopyPropagator().rewrite(treeNode);
-    traceGraph('Copy propagation', treeNode);
-    new LoopRewriter().rewrite(treeNode);
-    traceGraph('Loop rewriter', treeNode);
-    new LogicalRewriter().rewrite(treeNode);
-    traceGraph('Logical rewriter', treeNode);
-    new backend_ast_emitter.UnshadowParameters().unshadow(treeNode);
-    traceGraph('Unshadow parameters', treeNode);
-    return treeNode;
+  static bool checkTreeIntegrity(tree_ir.ExecutableDefinition node) {
+    new CheckTreeIntegrity().check(node);
+    return true; // So this can be used from assert().
+  }
+
+  tree_ir.FunctionDefinition optimizeTreeIR(tree_ir.FunctionDefinition node) {
+    void applyTreePass(String name, tree_opt.Pass pass) {
+      pass.rewrite(node);
+      traceGraph(name, node);
+      assert(checkTreeIntegrity(node));
+    }
+
+    applyTreePass('Statement rewriter', new StatementRewriter());
+    applyTreePass('Copy propagation', new CopyPropagator());
+    applyTreePass('Loop rewriter', new LoopRewriter());
+    applyTreePass('Logical rewriter', new LogicalRewriter());
+
+    return node;
   }
 
   js.Fun compileToJavaScript(CodegenWorkItem work,
                              tree_ir.FunctionDefinition definition) {
     CodeGenerator codeGen = new CodeGenerator(glue, work.registry);
 
     return attachPosition(codeGen.buildFunction(definition), work.element);
   }
 
   Iterable<CompilerTask> get tasks {
     // TODO(sigurdm): Make a better list of tasks.
     return <CompilerTask>[irBuilderTask]..addAll(fallbackCompiler.tasks);
   }
 
   js.Node attachPosition(js.Node node, AstElement element) {
     return node.withSourceInformation(
         StartEndSourceInformation.computeSourceInformation(element));
   }
 }