Read platform.dill in the VM.

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:kernel/binary/ast_to_binary.dart' show BinaryPrinter;
 
+import 'package:kernel/binary/tag.dart' show Tag;
+
 import 'package:kernel/kernel.dart' show Program;
 
 import 'package:kernel/target/targets.dart' show Target, TargetFlags, getTarget;
 
 import 'compiler_command_line.dart' show CompilerCommandLine;
 
 import 'compiler_context.dart' show CompilerContext;
 
 import 'errors.dart' show InputError, formatUnexpected, inputError, reportCrash;
 
@@ skipping 118 matching lines @@
   Future<Uri> compile() async {
     KernelTarget kernelTarget = await buildOutline();
     if (exitCode != 0) return null;
     Uri uri = c.options.output;
     await kernelTarget.writeProgram(uri,
         dumpIr: c.options.dumpIr, verify: c.options.verify);
     return uri;
   }
 }
 
+class FrontEndBinaryPrinter extends BinaryPrinter {

[Kevin Millikin (Google), 2017/03/31 10:05:42]

This is hacky and I'm sure there is a better way.  I'll figure out what we
really want to do for now before committing.

[ahe, 2017/03/31 10:13:09]

I think this would be a better fit for the "kernel" subdirectory.

[ahe, 2017/03/31 10:13:09]

How about renaming this FilteringBinaryPrinter and add this method:

bool includeLibrary(Library library) => !library.importUri.isScheme('dart');

+  FrontEndBinaryPrinter(Sink<List<int>> sink) : super(sink);
+
+  void writeProgramFile(Program program) {
+    program.computeCanonicalNames();
+    writeMagicWord(Tag.ProgramFile);
+    stringIndexer.scanProgram(program);
+    writeStringTable(stringIndexer);
+    writeUriToSource(program);
+    writeLinkTable(program);
+    writeList(program.libraries.where((lib) => !lib.importUri.isScheme('dart')),
+        writeNode);
+    writeMemberReference(program.mainMethod, allowNull: true);
+    flush();
+  }
+}
+
 Future<CompilationResult> parseScript(
     Uri fileName, Uri packages, Uri patchedSdk, bool verbose) async {
   try {
     if (!await new File.fromUri(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."));
@@ skipping 21 matching lines @@
     } on InputError catch (e) {
       return new CompilationResult.error(e.format());
     }
 
     // Perform target-specific transformations.
     target.performModularTransformations(program);
     target.performGlobalTransformations(program);
 
     // Write the program to a list of bytes and return it.
     var sink = new ByteSink();
-    new BinaryPrinter(sink).writeProgramFile(program);
+    new FrontEndBinaryPrinter(sink).writeProgramFile(program);
     return new CompilationResult.ok(sink.builder.takeBytes());
   } catch (e, s) {
     return reportCrash(e, s, fileName);
   }
 }
 
 Future compilePlatform(Uri patchedSdk, Uri output,
     {Uri packages, bool verbose: false}) async {
   Ticker ticker = new Ticker(isVerbose: verbose);
   await CompilerCommandLine.withGlobalOptions("", [""], (CompilerContext c) {
@@ skipping 39 matching lines @@
   final BytesBuilder builder = new BytesBuilder();
 
   void add(List<int> data) {
     builder.add(data);
   }
 
   void close() {
     // Nothing to do.
   }
 }