[vm/infra] Improve IL testing framework

* Add support for dumping flow graphs in JSON (to make it machine
readable);
* Add support for controlling which functions are dumped through
a pragma annotation:
`@pragma('vm:testing:print-flow-graph'[, "passes filter"])`
* Replace simple matching DSL with programmatic matching
* Support obfuscated builds

Fixes #47340

TEST=vm/dart{,_2}/aot_prefer_equality_comparison_il_test

Cq-Include-Trybots: luci.dart.try:vm-kernel-precomp-linux-debug-x64-try,vm-kernel-precomp-linux-product-x64-try,vm-kernel-precomp-linux-release-x64-try
Change-Id: Ie067ba451d311e6019a8c3a88c012231b0c50eb5
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/219240
Commit-Queue: Slava Egorov <vegorov@google.com>
Reviewed-by: Alexander Markov <alexmarkov@google.com>

Author: mraleph

pkg/test_runner/lib/src/compiler_configuration.dart

@@ -828,6 +828,9 @@ class PrecompilerCompilerConfiguration extends CompilerConfiguration
       if (_configuration.useQemu) '--no-use-integer-division',
       if (arguments.contains('--print-flow-graph-optimized'))
         '--redirect-isolate-log-to=$tempDir/out.il',
+      if (arguments.contains('--print-flow-graph-optimized') &&
+          (_configuration.isMinified || arguments.contains('--obfuscate')))
+        '--save-obfuscation_map=$tempDir/renames.json',
       ..._replaceDartFiles(arguments, tempKernelFile(tempDir)),
     ];
 
@@ -844,6 +847,7 @@ class PrecompilerCompilerConfiguration extends CompilerConfiguration
     var args = [
       arguments.firstWhere((arg) => arg.endsWith('_il_test.dart')),
       '$tempDir/out.il',
+      if (arguments.contains('--obfuscate')) '$tempDir/renames.json',
     ];
 
     return CompilationCommand('compare_il', tempDir, bootstrapDependencies(),
@@ -965,9 +969,10 @@ class PrecompilerCompilerConfiguration extends CompilerConfiguration
   List<String> computeCompilerArguments(
       TestFile testFile, List<String> vmOptions, List<String> args) {
     return [
-      if (testFile.ilMatches.isNotEmpty) ...[
+      if (testFile.isVmIntermediateLanguageTest) ...[
         '--print-flow-graph-optimized',
-        '--print-flow-graph-filter=${testFile.ilMatches.join(',')}'
+        '--print-flow-graph-as-json',
+        '--print-flow-graph-filter=@pragma',
       ],
       if (_enableAsserts) '--enable_asserts',
       ...filterVmOptions(vmOptions),

pkg/test_runner/lib/src/test_file.dart

@@ -211,10 +211,7 @@ class TestFile extends _TestFileBase {
       throw FormatException('Unknown feature "$name" in test $filePath');
     });
 
-    var ilMatches = filePath.endsWith('_il_test.dart')
-        ? _parseStringOption(filePath, contents, r'MatchIL\[AOT\]',
-            allowMultiple: true)
-        : const <String>[];
+    final isVmIntermediateLanguageTest = filePath.endsWith('_il_test.dart');
 
     // VM options.
     var vmOptions = <List<String>>[];
@@ -341,7 +338,7 @@ class TestFile extends _TestFileBase {
         sharedObjects: sharedObjects,
         otherResources: otherResources,
         experiments: experiments,
-        ilMatches: ilMatches);
+        isVmIntermediateLanguageTest: isVmIntermediateLanguageTest);
   }
 
   /// A special fake test file for representing a VM unit test written in C++.
@@ -363,7 +360,7 @@ class TestFile extends _TestFileBase {
         sharedObjects = [],
         otherResources = [],
         experiments = [],
-        ilMatches = [],
+        isVmIntermediateLanguageTest = false,
         super(null, null, []);
 
   TestFile._(Path suiteDirectory, Path path, List<StaticError> expectedErrors,
@@ -384,7 +381,7 @@ class TestFile extends _TestFileBase {
       this.sharedObjects,
       this.otherResources,
       this.experiments,
-      this.ilMatches = const <String>[]})
+      this.isVmIntermediateLanguageTest = false})
       : super(suiteDirectory, path, expectedErrors) {
     assert(!isMultitest || dartOptions.isEmpty);
   }
@@ -403,6 +400,7 @@ class TestFile extends _TestFileBase {
   final bool hasRuntimeError;
   final bool hasStaticWarning;
   final bool hasCrash;
+  final bool isVmIntermediateLanguageTest;
 
   /// The features that a test configuration must support in order to run this
   /// test.
@@ -411,9 +409,6 @@ class TestFile extends _TestFileBase {
   /// requirements, the test is implicitly skipped.
   final List<Feature> requirements;
 
-  /// List of functions which will have their IL verified (in AOT mode).
-  final List<String> ilMatches;
-
   final List<String> sharedOptions;
   final List<String> dartOptions;
   final List<String> dart2jsOptions;
@@ -479,6 +474,7 @@ class _MultitestFile extends _TestFileBase implements TestFile {
   final bool hasStaticWarning;
   final bool hasSyntaxError;
   bool get hasCrash => _origin.hasCrash;
+  bool get isVmIntermediateLanguageTest => _origin.isVmIntermediateLanguageTest;
 
   _MultitestFile(this._origin, Path path, this.multitestKey,
       List<StaticError> expectedErrors,
@@ -493,7 +489,6 @@ class _MultitestFile extends _TestFileBase implements TestFile {
   String get packages => _origin.packages;
 
   List<Feature> get requirements => _origin.requirements;
-  List<String> get ilMatches => _origin.ilMatches;
   List<String> get dart2jsOptions => _origin.dart2jsOptions;
   List<String> get dartOptions => _origin.dartOptions;
   List<String> get ddcOptions => _origin.ddcOptions;