[Fasta] Enable running the constant evaluation pass
The experimental flag `constant-update-2018` selects front-end
constant evaluation. The transformation is run before performing any
backend-specific transformations.
Compiling dart2js in strong mode goes from 12 seconds to between 12.3
and 12.5 (with more variability, apparently).
Change-Id: I279f0e60a3197b4fb077a1e9641ea92cf1409612
Reviewed-on: https://dart-review.googlesource.com/c/88701
Commit-Queue: Kevin Millikin <kmillikin@google.com>
Reviewed-by: Peter von der Ahé <ahe@google.com>
Reviewed-by: Aske Simon Christensen <askesc@google.com>
diff --git a/pkg/front_end/lib/src/api_prototype/experimental_flags.dart b/pkg/front_end/lib/src/api_prototype/experimental_flags.dart
index 3f0c4bc..1441108 100644
--- a/pkg/front_end/lib/src/api_prototype/experimental_flags.dart
+++ b/pkg/front_end/lib/src/api_prototype/experimental_flags.dart
@@ -4,12 +4,17 @@
// TODO(askesc): Generate this file from a flag specification.
-enum ExperimentalFlag { setLiterals }
+enum ExperimentalFlag {
+ setLiterals,
+ constantUpdate2018,
+}
ExperimentalFlag parseExperimentalFlag(String flag) {
switch (flag) {
case "set-literals":
return ExperimentalFlag.setLiterals;
+ case "constant-update-2018":
+ return ExperimentalFlag.constantUpdate2018;
}
return null;
}
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_constants.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_constants.dart
new file mode 100644
index 0000000..b7372a5
--- /dev/null
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_constants.dart
@@ -0,0 +1,48 @@
+// Copyright (c) 2019, 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.kernel_constants;
+
+import 'package:kernel/ast.dart'
+ show
+ Constant,
+ DartType,
+ ListConstant,
+ MapConstant,
+ NullConstant,
+ StaticInvocation,
+ TreeNode;
+
+import 'package:kernel/transformations/constants.dart'
+ show ConstantsBackend, ErrorReporter;
+
+import '../problems.dart' show unimplemented;
+
+class KernelConstantsBackend extends ConstantsBackend {
+ @override
+ Constant lowerListConstant(ListConstant constant) => constant;
+
+ @override
+ Constant lowerMapConstant(MapConstant constant) => constant;
+
+ @override
+ Constant buildConstantForNative(
+ String nativeName,
+ List<DartType> typeArguments,
+ List<Constant> positionalArguments,
+ Map<String, Constant> namedArguments,
+ List<TreeNode> context,
+ StaticInvocation node,
+ ErrorReporter errorReporter,
+ void abortEvaluation()) {
+ // VM-specific names of the fromEnvironment factory constructors.
+ if (nativeName == 'Bool_fromEnvironment' ||
+ nativeName == 'Integer_fromEnvironment' ||
+ nativeName == 'String_fromEnvironment') {
+ return namedArguments['defaultValue'] ?? new NullConstant();
+ }
+ return unimplemented('constant evaluation of ${nativeName}',
+ node.fileOffset, node.location.file);
+ }
+}
diff --git a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
index e917fb8..39ea072 100644
--- a/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
+++ b/pkg/front_end/lib/src/fasta/kernel/kernel_target.dart
@@ -41,6 +41,11 @@
import 'package:kernel/type_algebra.dart' show substitute;
+import 'package:kernel/type_environment.dart' show TypeEnvironment;
+
+import 'package:kernel/transformations/constants.dart' as constants
+ show transformLibraries;
+
import '../../api_prototype/file_system.dart' show FileSystem;
import '../compiler_context.dart' show CompilerContext;
@@ -64,7 +69,7 @@
templateMissingImplementationCause,
templateSuperclassHasNoDefaultConstructor;
-import '../problems.dart' show unhandled;
+import '../problems.dart' show unhandled, unimplemented;
import '../severity.dart' show Severity;
@@ -93,6 +98,8 @@
TypeBuilder,
TypeDeclarationBuilder;
+import 'kernel_constants.dart' show KernelConstantsBackend;
+
import 'metadata_collector.dart' show MetadataCollector;
import 'verifier.dart' show verifyComponent;
@@ -741,12 +748,25 @@
/// Run all transformations that are needed when building a bundle of
/// libraries for the first time.
void runBuildTransformations() {
+ if (loader.target.enableConstantUpdate2018) {
+ constants.transformLibraries(
+ loader.libraries,
+ new KernelConstantsBackend(),
+ loader.coreTypes,
+ new TypeEnvironment(loader.coreTypes, loader.hierarchy,
+ legacyMode: false));
+ ticker.logMs("Evaluated constants");
+ }
backendTarget.performModularTransformationsOnLibraries(
component, loader.coreTypes, loader.hierarchy, loader.libraries,
logger: (String msg) => ticker.logMs(msg));
}
void runProcedureTransformations(Procedure procedure) {
+ if (loader.target.enableConstantUpdate2018) {
+ unimplemented('constant evaluation during expression evaluation',
+ procedure.fileOffset, procedure.fileUri);
+ }
backendTarget.performTransformationsOnProcedure(
loader.coreTypes, loader.hierarchy, procedure,
logger: (String msg) => ticker.logMs(msg));
diff --git a/pkg/front_end/lib/src/fasta/target_implementation.dart b/pkg/front_end/lib/src/fasta/target_implementation.dart
index 6c8f046..2705f16 100644
--- a/pkg/front_end/lib/src/fasta/target_implementation.dart
+++ b/pkg/front_end/lib/src/fasta/target_implementation.dart
@@ -36,10 +36,13 @@
Declaration cachedNativeExtensionAnnotation;
bool enableSetLiterals;
+ bool enableConstantUpdate2018;
TargetImplementation(Ticker ticker, this.uriTranslator, this.backendTarget)
: enableSetLiterals = CompilerContext.current.options
.isExperimentEnabled(ExperimentalFlag.setLiterals),
+ enableConstantUpdate2018 = CompilerContext.current.options
+ .isExperimentEnabled(ExperimentalFlag.constantUpdate2018),
super(ticker);
/// Creates a [LibraryBuilder] corresponding to [uri], if one doesn't exist
