Make array and object prototype singletons immutable for now

rollup · Jun 16, 2021 · 8383cf9 · 8383cf9
1 parent c4f9d13
commit 8383cf9
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Showing 3 changed files with 14 additions and 7 deletions.
diff --git a/src/ast/nodes/shared/ArrayPrototype.ts b/src/ast/nodes/shared/ArrayPrototype.ts
@@ -148,5 +148,6 @@ export const ARRAY_PROTOTYPE = new ObjectEntity(
 		unshift: METHOD_MUTATES_SELF_RETURNS_NUMBER,
 		values: METHOD_DEOPTS_SELF_RETURNS_UNKNOWN
 	} as unknown as PropertyMap,
-	OBJECT_PROTOTYPE
+	OBJECT_PROTOTYPE,
+	true
 );
diff --git a/src/ast/nodes/shared/ObjectEntity.ts b/src/ast/nodes/shared/ObjectEntity.ts
@@ -50,7 +50,8 @@ export class ObjectEntity extends ExpressionEntity {
 	// and we assume there are no setters or getters
 	constructor(
 		properties: ObjectProperty[] | PropertyMap,
-		private prototypeExpression: ExpressionEntity | null
+		private prototypeExpression: ExpressionEntity | null,
+		private immutable = false
 	) {
 		super();
 		if (Array.isArray(properties)) {
@@ -96,7 +97,7 @@ export class ObjectEntity extends ExpressionEntity {
 	}
 
 	deoptimizePath(path: ObjectPath): void {
-		if (this.hasUnknownDeoptimizedProperty) return;
+		if (this.hasUnknownDeoptimizedProperty || this.immutable) return;
 		const key = path[0];
 		if (path.length === 1) {
 			if (typeof key !== 'string') {
@@ -171,7 +172,9 @@ export class ObjectEntity extends ExpressionEntity {
 						property.deoptimizeThisOnEventAtPath(event, subPath, thisParameter, recursionTracker);
 					}
 				}
-				this.thisParametersToBeDeoptimized.add(thisParameter);
+				if (!this.immutable) {
+					this.thisParametersToBeDeoptimized.add(thisParameter);
+				}
 				return;
 			}
 			for (const property of relevantUnmatchableProperties) {
@@ -194,7 +197,9 @@ export class ObjectEntity extends ExpressionEntity {
 				property.deoptimizeThisOnEventAtPath(event, subPath, thisParameter, recursionTracker);
 			}
 		}
-		this.thisParametersToBeDeoptimized.add(thisParameter);
+		if (!this.immutable) {
+			this.thisParametersToBeDeoptimized.add(thisParameter);
+		}
 		this.prototypeExpression?.deoptimizeThisOnEventAtPath(
 			event,
 			path,
@@ -467,7 +472,7 @@ export class ObjectEntity extends ExpressionEntity {
 			return UNKNOWN_EXPRESSION;
 		}
 		const expression = this.getMemberExpression(key);
-		if (expression !== UNKNOWN_EXPRESSION) {
+		if (!(expression === UNKNOWN_EXPRESSION || this.immutable)) {
 			const expressionsToBeDeoptimized = (this.expressionsToBeDeoptimizedByKey[key] =
 				this.expressionsToBeDeoptimizedByKey[key] || []);
 			expressionsToBeDeoptimized.push(origin);

diff --git a/src/ast/nodes/shared/ObjectPrototype.ts b/src/ast/nodes/shared/ObjectPrototype.ts
@@ -15,5 +15,6 @@ export const OBJECT_PROTOTYPE = new ObjectEntity(
 		toString: METHOD_RETURNS_STRING,
 		valueOf: METHOD_RETURNS_UNKNOWN
 	} as unknown as PropertyMap,
-	null
+	null,
+	true
 );