Reapply "Use backend targets to run Kernel transformations in Fasta"

pkg/front_end/lib/src/fasta/fasta.dart

 // Copyright (c) 2016, 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.
 
 library fasta;
 
 import 'dart:async' show Future;
 
 import 'dart:convert' show JSON;
 
 import 'dart:io' show BytesBuilder, Directory, File, exitCode;
 
 import 'package:front_end/file_system.dart';
 import 'package:front_end/physical_file_system.dart';
 import 'package:front_end/src/fasta/kernel/utils.dart';
 import 'package:kernel/binary/ast_to_binary.dart'
     show LibraryFilteringBinaryPrinter;
 
-import 'package:kernel/class_hierarchy.dart' show ClassHierarchy;
-
-import 'package:kernel/core_types.dart' show CoreTypes;
-
 import 'package:kernel/kernel.dart' show Library, Program, loadProgramFromBytes;
 
-import 'package:kernel/target/targets.dart' show Target, TargetFlags, getTarget;
+import 'package:kernel/target/targets.dart' show TargetFlags;
 
 import 'compiler_command_line.dart' show CompilerCommandLine;
 
 import 'compiler_context.dart' show CompilerContext;
 
 import 'errors.dart' show InputError, formatUnexpected, inputError, reportCrash;
 
 import 'kernel/kernel_target.dart' show KernelTarget;
 
 import 'dill/dill_target.dart' show DillTarget;
@@ skipping 75 matching lines @@
   }
 }
 
 class CompileTask {
   final CompilerContext c;
   final Ticker ticker;
 
   CompileTask(this.c, this.ticker);
 
   DillTarget createDillTarget(TranslateUri uriTranslator) {
-    return new DillTarget(ticker, uriTranslator, c.options.target);
+    return new DillTarget(ticker, uriTranslator, c.options.target,
+        flags: new TargetFlags(strongMode: c.options.strongMode));
   }
 
   KernelTarget createKernelTarget(
       DillTarget dillTarget, TranslateUri uriTranslator, bool strongMode) {
     return new KernelTarget(
-        c.fileSystem, dillTarget, uriTranslator, strongMode, c.uriToSource);
+        c.fileSystem, dillTarget, uriTranslator, c.uriToSource);
   }
 
   Future<KernelTarget> buildOutline([Uri output]) async {
     TranslateUri uriTranslator = await TranslateUri
         .parse(c.fileSystem, c.options.sdk, packages: c.options.packages);
     ticker.logMs("Read packages file");
     DillTarget dillTarget = createDillTarget(uriTranslator);
     KernelTarget kernelTarget =
         createKernelTarget(dillTarget, uriTranslator, c.options.strongMode);
     if (c.options.strongMode) {
@@ skipping 41 matching lines @@
     Uri fileName, Uri packages, Uri patchedSdk,
     {bool verbose: false, bool strongMode: false}) async {
   return parseScriptInFileSystem(
       fileName, PhysicalFileSystem.instance, packages, patchedSdk,
       verbose: verbose, strongMode: strongMode);
 }
 
 Future<CompilationResult> parseScriptInFileSystem(
     Uri fileName, FileSystem fileSystem, Uri packages, Uri patchedSdk,
     {bool verbose: false, bool strongMode: false, String backendTarget}) async {
-  backendTarget ??= "vm";
+  backendTarget ??= "vm_fasta";
   try {
     if (!await fileSystem.entityForUri(fileName).exists()) {
       return new CompilationResult.error(
           formatUnexpected(fileName, -1, "No such file."));
     }
     if (!await new Directory.fromUri(patchedSdk).exists()) {
       return new CompilationResult.error(
           formatUnexpected(patchedSdk, -1, "Patched sdk directory not found."));
     }
 
-    CoreTypes coreTypes;
-    ClassHierarchy hierarchy;
     Program program;
     try {
       TranslateUri uriTranslator =
           await TranslateUri.parse(fileSystem, patchedSdk, packages: packages);
       final Ticker ticker = new Ticker(isVerbose: verbose);
-      final DillTarget dillTarget =
-          new DillTarget(ticker, uriTranslator, backendTarget);
+      final DillTarget dillTarget = new DillTarget(
+          ticker, uriTranslator, backendTarget,
+          flags: new TargetFlags(strongMode: strongMode));
       _appendDillForUri(dillTarget, patchedSdk.resolve('platform.dill'));
       final KernelTarget kernelTarget =
-          new KernelTarget(fileSystem, dillTarget, uriTranslator, strongMode);
+          new KernelTarget(fileSystem, dillTarget, uriTranslator);
       kernelTarget.read(fileName);
       await dillTarget.buildOutlines();
       await kernelTarget.buildOutlines();
-      coreTypes = kernelTarget.loader.coreTypes;
-      hierarchy = kernelTarget.loader.hierarchy;
       program = await kernelTarget.buildProgram();
       if (kernelTarget.errors.isNotEmpty) {
         return new CompilationResult.errors(kernelTarget.errors);
       }
     } on InputError catch (e) {
       return new CompilationResult.error(e.format());
     }
 
     if (program.mainMethod == null) {
       return new CompilationResult.error("No 'main' method found.");
     }
 
-    // Perform target-specific transformations.
-    Target target = getTarget("vm", new TargetFlags(strongMode: false));
-    target.performModularTransformations(coreTypes, hierarchy, program);
-    target.performGlobalTransformations(coreTypes, program);
-
     // Write the program to a list of bytes and return it.  Do not include
     // libraries that have a dart: import URI.
     //
     // TODO(kmillikin): This is intended to exclude platform libraries that are
     // included in the Kernel binary platform platform.dill.  It does not
     // necessarily exclude exactly the platform libraries.  Use a better
     // predicate that knows what is included in platform.dill.
     var sink = new ByteSink();
     bool predicate(Library library) => !library.importUri.isScheme('dart');
     new LibraryFilteringBinaryPrinter(sink, predicate)
         .writeProgramFile(program);
     return new CompilationResult.ok(sink.builder.takeBytes());
   } catch (e, s) {
     return reportCrash(e, s, fileName);
   }
 }
 
 Future compilePlatform(Uri patchedSdk, Uri fullOutput,
-    {Uri outlineOutput, Uri packages, bool verbose: false}) async {
+    {Uri outlineOutput,
+    Uri packages,
+    bool verbose: false,
+    String backendTarget}) async {
+  backendTarget ??= "vm_fasta";
   Ticker ticker = new Ticker(isVerbose: verbose);
   await CompilerCommandLine.withGlobalOptions("", [""], (CompilerContext c) {
+    c.options.options["--target"] = backendTarget;
     c.options.options["--packages"] = packages;
     if (verbose) {
       c.options.options["--verbose"] = true;
     }
     return compilePlatformInternal(
         c, ticker, patchedSdk, fullOutput, outlineOutput);
   });
 }
 
 Future writeDepsFile(Uri script, Uri depsFile, Uri output,
     {Uri sdk,
     Uri packages,
     Uri platform,
     Iterable<Uri> extraDependencies,
     bool verbose: false,
     String backendTarget}) async {
-  backendTarget ??= "vm";
+  backendTarget ??= "vm_fasta";
   Ticker ticker = new Ticker(isVerbose: verbose);
   await CompilerCommandLine.withGlobalOptions("", [""],
       (CompilerContext c) async {
     c.options.options["--packages"] = packages;
     if (verbose) {
       c.options.options["--verbose"] = true;
     }
     sdk ??= c.options.sdk;
 
     TranslateUri uriTranslator = await TranslateUri.parse(c.fileSystem, sdk,
         packages: c.options.packages);
     ticker.logMs("Read packages file");
-    DillTarget dillTarget =
-        new DillTarget(ticker, uriTranslator, backendTarget);
+    DillTarget dillTarget = new DillTarget(ticker, uriTranslator, backendTarget,
+        flags: new TargetFlags(strongMode: false));
     _appendDillForUri(dillTarget, platform);
-    KernelTarget kernelTarget = new KernelTarget(PhysicalFileSystem.instance,
-        dillTarget, uriTranslator, false, c.uriToSource);
+    KernelTarget kernelTarget = new KernelTarget(
+        PhysicalFileSystem.instance, dillTarget, uriTranslator, c.uriToSource);
 
     kernelTarget.read(script);
     await dillTarget.buildOutlines();
     await kernelTarget.loader.buildOutlines();
     await kernelTarget.writeDepsFile(output, depsFile,
         extraDependencies: extraDependencies);
   });
 }
 
 /// Load the [Program] from the given [uri] and append its libraries
@@ skipping 10 matching lines @@
   final BytesBuilder builder = new BytesBuilder();
 
   void add(List<int> data) {
     builder.add(data);
   }
 
   void close() {
     // Nothing to do.
   }
 }