[ddc] Delete old const canonicalization logic
There are only two consts in the SDK that triggered this code
path and they work fine with the standard const table canonicalization.
Change-Id: Ic3eb8f9c906869a6868eccccb455a46b7a873436
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/376021
Reviewed-by: Mark Zhou <markzipan@google.com>
Auto-Submit: Nicholas Shahan <nshahan@google.com>
Commit-Queue: Mark Zhou <markzipan@google.com>
diff --git a/pkg/dev_compiler/lib/src/compiler/shared_compiler.dart b/pkg/dev_compiler/lib/src/compiler/shared_compiler.dart
index ba51d59..6a93055 100644
--- a/pkg/dev_compiler/lib/src/compiler/shared_compiler.dart
+++ b/pkg/dev_compiler/lib/src/compiler/shared_compiler.dart
@@ -374,40 +374,6 @@
return js.call('#.# = #', args);
}
- /// Caches a constant (list/set/map or class instance) in a variable, so it's
- /// only canonicalized once at this location in the code, which improves
- /// performance.
- ///
- /// This method ensures the constant is not initialized until use.
- ///
- /// The expression [jsExpr] should contain the already-canonicalized constant.
- /// If the constant is not canonicalized yet, it should be wrapped in the
- /// appropriate call, such as:
- ///
- /// - dart.constList (for Lists),
- /// - dart.constMap (for Maps),
- /// - dart.constSet (for Sets),
- /// - dart.const (for other instances of classes)
- ///
- /// [canonicalizeConstObject] can be used for class instances; it will wrap
- /// the expression in `dart.const` and then call this method.
- ///
- /// If the same constant is used elsewhere (in this module, or another
- /// module), that will require a second canonicalization. In general it is
- /// uncommon to define the same large constant (such as lists, maps) in
- /// different locations, because that requires copy+paste, so in practice this
- /// optimization is rather effective (we should consider caching once
- /// per-module, though, as that would be relatively easy for the compiler to
- /// implement once we have a single Kernel backend).
- @protected
- js_ast.Expression cacheConst(js_ast.Expression jsExpr) {
- if (currentFunction == null) return jsExpr;
-
- var temp = js_ast.TemporaryId('const');
- moduleItems.add(js.statement('let #;', [temp]));
- return js.call('# || (# = #)', [temp, temp, jsExpr]);
- }
-
/// Emits a Dart Symbol with the given member [symbolName].
///
/// If the symbol refers to a private name, its library will be set to the
@@ -437,7 +403,7 @@
/// constant instance of a user-defined class stored in [expr].
@protected
js_ast.Expression canonicalizeConstObject(js_ast.Expression expr) =>
- cacheConst(runtimeCall('const(#)', [expr]));
+ runtimeCall('const(#)', [expr]);
/// Emits preamble for the module containing [libraries], and returns the
/// list of module items for further items to be added.
diff --git a/pkg/dev_compiler/lib/src/kernel/compiler.dart b/pkg/dev_compiler/lib/src/kernel/compiler.dart
index 8ccb39a..62f1529 100644
--- a/pkg/dev_compiler/lib/src/kernel/compiler.dart
+++ b/pkg/dev_compiler/lib/src/kernel/compiler.dart
@@ -4775,14 +4775,6 @@
visitConstant(node.constant);
@override
- js_ast.Expression canonicalizeConstObject(js_ast.Expression expr) {
- if (isSdkInternalRuntime(_currentLibrary!)) {
- return super.canonicalizeConstObject(expr);
- }
- return runtimeCall('const(#)', [expr]);
- }
-
- @override
js_ast.Expression visitVariableGet(VariableGet node) {
var v = node.variable;
var id = _emitVariableRef(v);
@@ -6924,8 +6916,7 @@
DartType elementType, List<js_ast.Expression> elements) {
// dart.constList helper internally depends on _interceptors.JSArray.
_declareBeforeUse(_jsArrayClass);
- return cacheConst(
- runtimeCall('constList([#], #)', [elements, _emitType(elementType)]));
+ return runtimeCall('constList([#], #)', [elements, _emitType(elementType)]);
}
@override
@@ -6946,8 +6937,7 @@
js_ast.Expression _emitConstSet(
DartType elementType, List<js_ast.Expression> elements) {
- return cacheConst(
- runtimeCall('constSet(#, [#])', [_emitType(elementType), elements]));
+ return runtimeCall('constSet(#, [#])', [_emitType(elementType), elements]);
}
@override
@@ -6973,8 +6963,8 @@
js_ast.Expression _emitConstMap(
DartType keyType, DartType valueType, List<js_ast.Expression> entries) {
- return cacheConst(runtimeCall('constMap(#, #, [#])',
- [_emitType(keyType), _emitType(valueType), entries]));
+ return runtimeCall('constMap(#, #, [#])',
+ [_emitType(keyType), _emitType(valueType), entries]);
}
/// Returns the key used for shape lookup at runtime.
@@ -7197,14 +7187,6 @@
}
@override
- js_ast.Expression cacheConst(js_ast.Expression jsExpr) {
- if (isSdkInternalRuntime(_currentLibrary!)) {
- return super.cacheConst(jsExpr);
- }
- return jsExpr;
- }
-
- @override
js_ast.Expression visitConstant(Constant node) {
if (node is StaticTearOffConstant) {
// JS() or external JS consts should not be lazily loaded.
@@ -7247,7 +7229,7 @@
type == const VoidType());
return _emitTypeLiteral(type);
}
- if (isSdkInternalRuntime(_currentLibrary!) || node is PrimitiveConstant) {
+ if (node is PrimitiveConstant) {
return super.visitConstant(node);
}
