Changes to allow the ClosureJsBackend to give people some options to play with:

- introduce a "fastDraft" mode that only runs the main code-removal passes and runs in about half the time and but produces code 2x the size (but still less than 10% of the original).
- allows it to run in an quasi-incremential mode by consuming the incrementially generated js (cuts ~4s off the build time but source maps are useless).
- allow source map generation to be turned off (saves a couple seconds).
- turns off not useful check passes and makes the rest switchable.

git-svn-id: https://dart.googlecode.com/svn/branches/bleeding_edge/dart@91 260f80e4-7a28-3924-810f-c04153c831b5

compiler/java/com/google/dart/compiler/backend/js/AbstractJsBackend.java

@@ -13,6 +13,7 @@ import com.google.common.collect.Multimap;
 import com.google.common.collect.Multimaps;
 import com.google.common.collect.Multiset;
 import com.google.dart.compiler.CommandLineOptions.CompilerOptions;
+import com.google.common.io.Closeables;
 import com.google.dart.compiler.DartCompilerContext;
 import com.google.dart.compiler.DartSource;
 import com.google.dart.compiler.ast.DartClass;
@@ -30,6 +31,8 @@ import com.google.dart.compiler.metrics.Tracer.TraceEvent;
 import com.google.dart.compiler.resolver.ClassElement;
 import com.google.dart.compiler.resolver.CoreTypeProvider;
 import com.google.dart.compiler.resolver.MethodElement;
+import com.google.dart.compiler.util.DefaultTextOutput;
+import com.google.dart.compiler.util.TextOutput;
 
 import java.io.IOException;
 import java.io.Writer;
@@ -51,6 +54,11 @@ import java.util.Set;
  */
 public abstract class AbstractJsBackend extends AbstractBackend {
 
+  public static final String EXTENSION_JS = "js";
+  public static final String EXTENSION_APP_JS = "app.js";
+  public static final String EXTENSION_JS_SRC_MAP = "js.map";
+  public static final String EXTENSION_APP_JS_SRC_MAP = "app.js.map";
+
   private static final String ROOT_PART_NAME = "";
   private static final String STATICS_PART_NAME = "$statics$";
   private static final String SEPARATOR_PART_NAME = "$seperator$";
@@ -468,5 +476,74 @@ public abstract class AbstractJsBackend extends AbstractBackend {
     return mangler.mangleEntryPoint(entry, context.getApplicationUnit().getElement());
   }
 
+  @Override
+  public boolean isOutOfDate(DartSource src, DartCompilerContext context) {
+    return context.isOutOfDate(src, src, EXTENSION_JS);
+  }
+
+  @Override
+  public void compileUnit(DartUnit unit, DartSource src, DartCompilerContext context,
+      CoreTypeProvider typeProvider) throws IOException {
+    // Translate the AST to JS.
+    Map<String, JsProgram> parts = translateToJS(unit, context, typeProvider);
+    String srcName = src.getName();
+
+    for (Map.Entry<String, JsProgram> entry : parts.entrySet()) {
+      // Generate Javascript output.
+      TextOutput out = new DefaultTextOutput(false);
+      JsToStringGenerationVisitor srcGenerator;
+      String name = entry.getKey();
+      boolean failed = true;
+      Writer w;
+
+      JsProgram program = entry.getValue();
+      JsBlock globalBlock = program.getGlobalBlock();
+
+      TraceEvent srcEvent =
+          Tracer.canTrace() ? Tracer.start(DartEventType.JS_SOURCE_GEN, "src", srcName, "name",
+              name) : null;
+      try {
+        srcGenerator = new JsSourceGenerationVisitor(out);
+
+        // TODO(johnlenz): Make source maps optional.
+        srcGenerator.generateSourceMap(true);
+
+        srcGenerator.accept(globalBlock);
+        w = context.getArtifactWriter(src, name, EXTENSION_JS);
+        try {
+          w.write(out.toString());
+          failed = false;
+        } finally {
+          Closeables.close(w, failed);
+        }
+      } finally {
+        Tracer.end(srcEvent);
+      }
+
+      /*
+       * Currently, out of date checks require that we write a JS file even if it is empty.
+       * However, we should not write a map file if it is.
+       */
+      if (!globalBlock.getStatements().isEmpty()) {
+        TraceEvent sourcemapEvent =
+            Tracer.canTrace() ? Tracer.start(DartEventType.WRITE_SOURCE_MAP, "src", srcName,
+                "name", name) : null;
+        try {
+          // Write out the source map.
+          w = context.getArtifactWriter(src, name, EXTENSION_JS_SRC_MAP);
+          failed = true;
+          try {
+            srcGenerator.writeSourceMap(w, src.getName());
+            failed = false;
+          } finally {
+            Closeables.close(w, failed);
+          }
+        } finally {
+          Tracer.end(sourcemapEvent);
+        }
+      }
+    }
+  }
+
   protected abstract boolean shouldOptimize();
 }

compiler/java/com/google/dart/compiler/backend/js/ClosureJsAst.java

@@ -30,11 +30,14 @@ public class ClosureJsAst implements SourceAst {
   private final Source source;
   private final InputId inputId;
 
-  public ClosureJsAst(JsProgram program, String inputName, Source source) {
+  private final boolean validate;
+
+  public ClosureJsAst(JsProgram program, String inputName, Source source, boolean validate) {
     assert(inputName != null);
     this.program = program;
     this.source = source;
     this.inputId = new InputId(inputName);
+    this.validate = validate;
   }
 
   @Override
@@ -71,6 +74,6 @@ public class ClosureJsAst implements SourceAst {
   }
 
   private void createAst(AbstractCompiler compiler) {
-    root = new ClosureJsAstTranslator().translate(program, inputId, source);
+    root = new ClosureJsAstTranslator(validate).translate(program, inputId, source);
   }
 }

compiler/java/com/google/dart/compiler/backend/js/ClosureJsAstTranslator.java

@@ -78,6 +78,12 @@ public class ClosureJsAstTranslator {
    private final Map<Source, StaticSourceFile> sourceCache =
        new HashMap<Source, StaticSourceFile>();
 
+   private final boolean validate;
+
+   ClosureJsAstTranslator(boolean validate) {
+     this.validate = validate;
+   }
+
    private StaticSourceFile getClosureSourceFile(Source source) {
      StaticSourceFile closureSourceFile = sourceCache.get(source);
      if (closureSourceFile == null) {
@@ -97,7 +103,9 @@ public class ClosureJsAstTranslator {
        script.addChildToBack(transform(s));
      }
      // Validate the structural integrity of the AST.
-     new AstValidator().validateScript(script);
+     if (validate) {
+       new AstValidator().validateScript(script);
+     }
      return script;
    }
 

compiler/java/com/google/dart/compiler/backend/js/ClosureJsBackend.java

@@ -12,6 +12,7 @@ import com.google.common.collect.Sets;
 import com.google.common.io.CharStreams;
 import com.google.common.io.Closeables;
 import com.google.common.io.LimitInputStream;
+import com.google.dart.compiler.CommandLineOptions;
 import com.google.dart.compiler.DartCompilationError;
 import com.google.dart.compiler.DartCompilerContext;
 import com.google.dart.compiler.DartSource;
@@ -20,10 +21,16 @@ import com.google.dart.compiler.Source;
 import com.google.dart.compiler.ast.DartUnit;
 import com.google.dart.compiler.ast.LibraryNode;
 import com.google.dart.compiler.ast.LibraryUnit;
+import com.google.dart.compiler.backend.js.ast.JsBlock;
 import com.google.dart.compiler.backend.js.ast.JsProgram;
 import com.google.dart.compiler.common.SourceInfo;
 import com.google.dart.compiler.metrics.CompilerMetrics;
+import com.google.dart.compiler.metrics.DartEventType;
+import com.google.dart.compiler.metrics.Tracer;
+import com.google.dart.compiler.metrics.Tracer.TraceEvent;
 import com.google.dart.compiler.resolver.CoreTypeProvider;
+import com.google.dart.compiler.util.DefaultTextOutput;
+import com.google.dart.compiler.util.TextOutput;
 import com.google.javascript.jscomp.CheckLevel;
 import com.google.javascript.jscomp.CompilationLevel;
 import com.google.javascript.jscomp.Compiler;
@@ -33,8 +40,12 @@ import com.google.javascript.jscomp.DiagnosticGroups;
 import com.google.javascript.jscomp.JSError;
 import com.google.javascript.jscomp.JSModule;
 import com.google.javascript.jscomp.JSSourceFile;
+import com.google.javascript.jscomp.PropertyRenamingPolicy;
 import com.google.javascript.jscomp.Result;
 import com.google.javascript.jscomp.SourceAst;
+import com.google.javascript.jscomp.SourceMap.DetailLevel;
+import com.google.javascript.jscomp.SourceMap.Format;
+import com.google.javascript.jscomp.VariableRenamingPolicy;
 import com.google.javascript.jscomp.WarningLevel;
 
 import java.io.IOException;
@@ -58,8 +69,8 @@ import java.util.zip.ZipInputStream;
  * @author johnlenz@google.com (John Lenz)
  */
 public class ClosureJsBackend extends AbstractJsBackend {
-  public static final String EXTENSION_JS = "opt.js";
-  public static final String EXTENSION_JS_SRC_MAP = "opt.js.map";
+  private static final String EXTENSION_OPT_JS = "opt.js";
+  private static final String EXTENSION_OPT_JS_SRC_MAP = "opt.js.map";
 
   // A map of possible input sources to use when building the optimized output.
   private Map<String, DartUnit> dartSrcToUnitMap = Maps.newHashMap();
@@ -67,27 +78,58 @@ public class ClosureJsBackend extends AbstractJsBackend {
 
   // Generate "readable" output for debugging
   private final boolean generateHumanReadableOutput;
+  // Generate "good" instead of "best" output.
+  private final boolean fastOutput;
+  // TODO(johnlenz): Currently we can only support incremential builds
+  // if we aren't building source maps.
+  private final boolean incremental;
+
+  private final boolean produceSourceMap;
+  // Validate the generated JavaScript
+  private final boolean validate;
 
   public ClosureJsBackend() {
-    this.generateHumanReadableOutput = false;
+    this(false);
   }
 
   /**
    * @param generateHumanReadableOutput - generates human readable javascript output.
    */
   public ClosureJsBackend(boolean generateHumanReadableOutput) {
+    // Current default settings
+    this(false, true, false, true, generateHumanReadableOutput);
+  }
+
+  public ClosureJsBackend(boolean fastOutput,
+                          boolean produceSourceMap,
+                          boolean incremental,
+                          boolean validate,
+                          boolean generateHumanReadableOutput) {
+    this.fastOutput = fastOutput;
+    this.produceSourceMap = produceSourceMap;
+    // can't currently produce a valid source map incrementally
+    this.incremental = incremental && !produceSourceMap;
+    this.validate = validate;
     this.generateHumanReadableOutput = generateHumanReadableOutput;
   }
 
   @Override
   public boolean isOutOfDate(DartSource src, DartCompilerContext context) {
-    return true;
+    if (!incremental) {
+      return true;
+    } else {
+      return super.isOutOfDate(src, context);
+    }
   }
 
   @Override
   public void compileUnit(DartUnit unit, DartSource src,
-      DartCompilerContext context, CoreTypeProvider typeProvider) {
-    dartSrcToUnitMap.put(src.getName(), unit);
+      DartCompilerContext context, CoreTypeProvider typeProvider) throws IOException {
+    if (!incremental) {
+      dartSrcToUnitMap.put(src.getName(), unit);
+    } else {
+      super.compileUnit(unit, src, context, typeProvider);
+    }
   }
 
   private Map<String, CompilerInput> createClosureJsAst(Map<String,JsProgram> parts, Source source) {
@@ -98,7 +140,7 @@ public class ClosureJsBackend extends AbstractJsBackend {
     for (Map.Entry<String,JsProgram> part : parts.entrySet()) {
       String partName = part.getKey();
       String inputName = name + ':' + partName;
-      SourceAst sourceAst = new ClosureJsAst(part.getValue(), inputName, source);
+      SourceAst sourceAst = new ClosureJsAst(part.getValue(), inputName, source, validate);
       CompilerInput input = new CompilerInput(sourceAst, false);
       translatedParts.put(part.getKey(), input);
     }
@@ -131,21 +173,38 @@ public class ClosureJsBackend extends AbstractJsBackend {
       StringWriter w = new StringWriter();
       Reader r = nativeSrc.getSourceReader();
       CharStreams.copy(r, w);
-      inputs.add(new CompilerInput(JSSourceFile.fromCode(name, w.toString()), false));
+      inputs.add(new CompilerInput(createSource(name, w), false));
     }
 
     @Override
-    public void visitPart(Part part) {
+    public void visitPart(Part part) throws IOException {
       DartSource src = part.unit.getSource();
-      Map<String, CompilerInput> translatedParts = translatedUnits.get(part.unit);
-      if (translatedParts == null) {
-        assert !sourcesByName.containsKey(src.getName());
-        sourcesByName.put(src.getName(), src);
-        Preconditions.checkNotNull(part.unit, "src: " + src.getName());
-        translatedParts = translateUnit(part.unit, src, context, typeProvider);
-        translatedUnits.put(part.unit, translatedParts);
+      if (!incremental) {
+        Map<String, CompilerInput> translatedParts = translatedUnits.get(part.unit);
+        if (translatedParts == null) {
+          assert !sourcesByName.containsKey(src.getName());
+          sourcesByName.put(src.getName(), src);
+          Preconditions.checkNotNull(part.unit, "src: " + src.getName());
+          translatedParts = translateUnit(part.unit, src, context, typeProvider);
+          Preconditions.checkState(!translatedUnits.containsKey(part.unit));
+          translatedUnits.put(part.unit, translatedParts);
+        }
+        inputs.add(translatedParts.get(part.part));
+        return;
       }
-      inputs.add(translatedParts.get(part.part));
+
+      Reader r = context.getArtifactReader(src, part.part, EXTENSION_JS);
+      if (r == null) {
+        return;
+      }
+      StringWriter w = new StringWriter();
+      CharStreams.copy(r, w);
+      String inputName = src.getName() + ':' + part.part;
+      inputs.add(new CompilerInput(createSource(inputName, w), false));
+    }
+
+    private JSSourceFile createSource(String name, Writer w) {
+      return JSSourceFile.fromCode(name, w.toString());
     }
   }
 
@@ -162,7 +221,7 @@ public class ClosureJsBackend extends AbstractJsBackend {
     DependencyBuilder.build(context.getAppLibraryUnit(), callback);
 
     // Lastly, add the entry point.
-    inputs.add( getCompilerInputForEntry(context) );
+    inputs.add(getCompilerInputForEntry(context));
 
     // Currently, there is only a single module, add all the sources to it.
     JSModule mainModule = new JSModule("main");
@@ -172,10 +231,10 @@ public class ClosureJsBackend extends AbstractJsBackend {
       }
     }
 
-    Writer out = context.getArtifactWriter(app, "", EXTENSION_JS);
+    Writer out = context.getArtifactWriter(app, "", getAppExtension());
     boolean failed = true;
     try {
-      Writer srcMapOut = context.getArtifactWriter(app, "", EXTENSION_JS_SRC_MAP);
+      Writer srcMapOut = context.getArtifactWriter(app, "", getSourceMapExtension());
       boolean failed2 = true;
       try {
         compileModule(
@@ -318,16 +377,15 @@ public class ClosureJsBackend extends AbstractJsBackend {
       Writer out, Writer srcMapOut)
       throws IOException {
     if (result.success) {
+      // TODO(johnlenz): Append directly to the writer.
       String output = compiler.toSource(module);
       out.append(output);
       out.append('\n');
 
-      compiler.getSourceMap().appendTo(srcMapOut, module.getName());
-
+      if (produceSourceMap) {
+        compiler.getSourceMap().appendTo(srcMapOut, module.getName());
+      }
       totalJsOutputCharCount = output.length();
-
-      // TODO(johnlenz): Output the externs declarations
-      // TODO(johnlenz): Output the manifest.
     }
 
     // return 0 if no errors, the error count otherwise

compiler/java/com/google/dart/compiler/backend/js/JavascriptBackend.java

@@ -38,11 +38,6 @@ import java.util.Map;
  */
 public class JavascriptBackend extends AbstractJsBackend  {
 
-  public static final String EXTENSION_JS = "js";
-  public static final String EXTENSION_APP_JS = "app.js";
-  public static final String EXTENSION_JS_SRC_MAP = "js.map";
-  public static final String EXTENSION_APP_JS_SRC_MAP = "app.js.map";
-
   /**
    * Wraps an Appendable and keeps track of the current offset as line/columns.
    */
@@ -180,75 +175,6 @@ public class JavascriptBackend extends AbstractJsBackend  {
     }
   }
 
-  @Override
-  public boolean isOutOfDate(DartSource src, DartCompilerContext context) {
-    return context.isOutOfDate(src, src, EXTENSION_JS);
-  }
-
-  @Override
-  public void compileUnit(DartUnit unit, DartSource src, DartCompilerContext context,
-      CoreTypeProvider typeProvider) throws IOException {
-    // Translate the AST to JS.
-    Map<String, JsProgram> parts = translateToJS(unit, context, typeProvider);
-    String srcName = src.getName();
-
-    for (Map.Entry<String, JsProgram> entry : parts.entrySet()) {
-      // Generate Javascript output.
-      TextOutput out = new DefaultTextOutput(false);
-      JsToStringGenerationVisitor srcGenerator;
-      String name = entry.getKey();
-      boolean failed = true;
-      Writer w;
-
-      JsProgram program = entry.getValue();
-      JsBlock globalBlock = program.getGlobalBlock();
-      
-      TraceEvent srcEvent =
-          Tracer.canTrace() ? Tracer.start(DartEventType.JS_SOURCE_GEN, "src", srcName, "name",
-              name) : null;
-      try {
-        srcGenerator = new JsSourceGenerationVisitor(out);
-
-        // TODO(johnlenz): Make source maps optional.
-        srcGenerator.generateSourceMap(true);
-
-        srcGenerator.accept(globalBlock);
-        w = context.getArtifactWriter(src, name, EXTENSION_JS);
-        try {
-          w.write(out.toString());
-          failed = false;
-        } finally {
-          Closeables.close(w, failed);
-        }
-      } finally {
-        Tracer.end(srcEvent);
-      }
-
-      /*
-       * Currently, out of date checks require that we write a JS file even if it is empty.  
-       * However, we should not write a map file if it is.
-       */
-      if (!globalBlock.getStatements().isEmpty()) {
-        TraceEvent sourcemapEvent =
-            Tracer.canTrace() ? Tracer.start(DartEventType.WRITE_SOURCE_MAP, "src", srcName,
-                "name", name) : null;
-        try {
-          // Write out the source map.
-          w = context.getArtifactWriter(src, name, EXTENSION_JS_SRC_MAP);
-          failed = true;
-          try {
-            srcGenerator.writeSourceMap(w, src.getName());
-            failed = false;
-          } finally {
-            Closeables.close(w, failed);
-          }
-        } finally {
-          Tracer.end(sourcemapEvent);
-        }
-      }
-    }
-  }
-
   @Override
   public void packageApp(LibrarySource app,
                          Collection<LibraryUnit> libraries,