diff --git a/src/ast/nodes/ArrowFunctionExpression.ts b/src/ast/nodes/ArrowFunctionExpression.ts
index 8bf2df38572..c99578c872e 100644
--- a/src/ast/nodes/ArrowFunctionExpression.ts
+++ b/src/ast/nodes/ArrowFunctionExpression.ts
@@ -5,8 +5,9 @@ import type ChildScope from '../scopes/ChildScope';
 import ReturnValueScope from '../scopes/ReturnValueScope';
 import { type ObjectPath } from '../utils/PathTracker';
 import type BlockStatement from './BlockStatement';
+import type CallExpression from './CallExpression';
 import Identifier from './Identifier';
-import type * as NodeType from './NodeType';
+import * as NodeType from './NodeType';
 import { Flag, isFlagSet, setFlag } from './shared/BitFlags';
 import FunctionBase from './shared/FunctionBase';
 import type { ExpressionNode, IncludeChildren } from './shared/Node';
@@ -67,6 +68,13 @@ export default class ArrowFunctionExpression extends FunctionBase {
 		return false;
 	}
 
+	protected onlyFunctionCallUsed(): boolean {
+		const isIIFE =
+			this.parent.type === NodeType.CallExpression &&
+			(this.parent as CallExpression).callee === this;
+		return isIIFE || super.onlyFunctionCallUsed();
+	}
+
 	include(context: InclusionContext, includeChildrenRecursively: IncludeChildren): void {
 		super.include(context, includeChildrenRecursively);
 		for (const parameter of this.params) {
diff --git a/src/ast/nodes/CallExpression.ts b/src/ast/nodes/CallExpression.ts
index 737f1a21eef..85ddcaeaffa 100644
--- a/src/ast/nodes/CallExpression.ts
+++ b/src/ast/nodes/CallExpression.ts
@@ -63,20 +63,17 @@ export default class CallExpression
 	}
 
 	hasEffects(context: HasEffectsContext): boolean {
-		try {
-			for (const argument of this.arguments) {
-				if (argument.hasEffects(context)) return true;
-			}
-			if (this.annotationPure) {
-				return false;
-			}
-			return (
-				this.callee.hasEffects(context) ||
-				this.callee.hasEffectsOnInteractionAtPath(EMPTY_PATH, this.interaction, context)
-			);
-		} finally {
-			if (!this.deoptimized) this.applyDeoptimizations();
+		if (!this.deoptimized) this.applyDeoptimizations();
+		for (const argument of this.arguments) {
+			if (argument.hasEffects(context)) return true;
 		}
+		if (this.annotationPure) {
+			return false;
+		}
+		return (
+			this.callee.hasEffects(context) ||
+			this.callee.hasEffectsOnInteractionAtPath(EMPTY_PATH, this.interaction, context)
+		);
 	}
 
 	include(context: InclusionContext, includeChildrenRecursively: IncludeChildren): void {
diff --git a/src/ast/nodes/FunctionDeclaration.ts b/src/ast/nodes/FunctionDeclaration.ts
index 4f75fce15f4..9cfa8b21bd5 100644
--- a/src/ast/nodes/FunctionDeclaration.ts
+++ b/src/ast/nodes/FunctionDeclaration.ts
@@ -14,6 +14,11 @@ export default class FunctionDeclaration extends FunctionNode {
 		}
 	}
 
+	protected onlyFunctionCallUsed(): boolean {
+		// call super.onlyFunctionCallUsed for export default anonymous function
+		return this.id?.variable.getOnlyFunctionCallUsed() ?? super.onlyFunctionCallUsed();
+	}
+
 	parseNode(esTreeNode: GenericEsTreeNode): this {
 		if (esTreeNode.id !== null) {
 			this.id = new Identifier(this, this.scope.parent as ChildScope).parseNode(
diff --git a/src/ast/nodes/FunctionExpression.ts b/src/ast/nodes/FunctionExpression.ts
index be7c5e43144..85b2b5cb45f 100644
--- a/src/ast/nodes/FunctionExpression.ts
+++ b/src/ast/nodes/FunctionExpression.ts
@@ -2,6 +2,7 @@ import type MagicString from 'magic-string';
 import { BLANK } from '../../utils/blank';
 import type { NodeRenderOptions, RenderOptions } from '../../utils/renderHelpers';
 import ChildScope from '../scopes/ChildScope';
+import type CallExpression from './CallExpression';
 import type { IdentifierWithVariable } from './Identifier';
 import Identifier from './Identifier';
 import * as NodeType from './NodeType';
@@ -25,6 +26,14 @@ export default class FunctionExpression extends FunctionNode {
 		return super.parseNode(esTreeNode);
 	}
 
+	protected onlyFunctionCallUsed(): boolean {
+		const isIIFE =
+			this.parent.type === NodeType.CallExpression &&
+			(this.parent as CallExpression).callee === this &&
+			(this.id === null || this.id.variable.getOnlyFunctionCallUsed());
+		return isIIFE || super.onlyFunctionCallUsed();
+	}
+
 	render(
 		code: MagicString,
 		options: RenderOptions,
diff --git a/src/ast/nodes/Identifier.ts b/src/ast/nodes/Identifier.ts
index 11147f3fb09..8bc4ffcd8ea 100644
--- a/src/ast/nodes/Identifier.ts
+++ b/src/ast/nodes/Identifier.ts
@@ -60,10 +60,12 @@ export default class Identifier extends NodeBase implements PatternNode {
 		}
 	}
 
+	private isReferenceVariable = false;
 	bind(): void {
 		if (!this.variable && isReference(this, this.parent as NodeWithFieldDefinition)) {
 			this.variable = this.scope.findVariable(this.name);
 			this.variable.addReference(this);
+			this.isReferenceVariable = true;
 		}
 	}
 
@@ -295,6 +297,10 @@ export default class Identifier extends NodeBase implements PatternNode {
 			this.variable.consolidateInitializers();
 			this.scope.context.requestTreeshakingPass();
 		}
+		if (this.isReferenceVariable) {
+			this.variable!.addUsedPlace(this);
+			this.scope.context.requestTreeshakingPass();
+		}
 	}
 
 	private getVariableRespectingTDZ(): ExpressionEntity | null {
diff --git a/src/ast/nodes/MemberExpression.ts b/src/ast/nodes/MemberExpression.ts
index 5c32a896b3d..7d6c6204731 100644
--- a/src/ast/nodes/MemberExpression.ts
+++ b/src/ast/nodes/MemberExpression.ts
@@ -396,6 +396,10 @@ export default class MemberExpression
 			);
 			this.scope.context.requestTreeshakingPass();
 		}
+		if (this.variable) {
+			this.variable.addUsedPlace(this);
+			this.scope.context.requestTreeshakingPass();
+		}
 	}
 
 	private applyAssignmentDeoptimization(): void {
diff --git a/src/ast/nodes/UpdateExpression.ts b/src/ast/nodes/UpdateExpression.ts
index 2d7b0613fe5..860bdd927a5 100644
--- a/src/ast/nodes/UpdateExpression.ts
+++ b/src/ast/nodes/UpdateExpression.ts
@@ -87,7 +87,7 @@ export default class UpdateExpression extends NodeBase {
 		this.argument.deoptimizePath(EMPTY_PATH);
 		if (this.argument instanceof Identifier) {
 			const variable = this.scope.findVariable(this.argument.name);
-			variable.isReassigned = true;
+			variable.markReassigned();
 		}
 		this.scope.context.requestTreeshakingPass();
 	}
diff --git a/src/ast/nodes/shared/FunctionBase.ts b/src/ast/nodes/shared/FunctionBase.ts
index 55b9f7f3da1..e6fc3fb83b7 100644
--- a/src/ast/nodes/shared/FunctionBase.ts
+++ b/src/ast/nodes/shared/FunctionBase.ts
@@ -10,11 +10,16 @@ import {
 import type ReturnValueScope from '../../scopes/ReturnValueScope';
 import type { ObjectPath, PathTracker } from '../../utils/PathTracker';
 import { UNKNOWN_PATH, UnknownKey } from '../../utils/PathTracker';
+import { UNDEFINED_EXPRESSION } from '../../values';
 import type ParameterVariable from '../../variables/ParameterVariable';
+import type Variable from '../../variables/Variable';
 import BlockStatement from '../BlockStatement';
+import type ExportDefaultDeclaration from '../ExportDefaultDeclaration';
 import Identifier from '../Identifier';
+import * as NodeType from '../NodeType';
 import RestElement from '../RestElement';
 import type SpreadElement from '../SpreadElement';
+import type VariableDeclarator from '../VariableDeclarator';
 import { Flag, isFlagSet, setFlag } from './BitFlags';
 import type { ExpressionEntity, LiteralValueOrUnknown } from './Expression';
 import { UNKNOWN_EXPRESSION, UNKNOWN_RETURN_EXPRESSION } from './Expression';
@@ -27,6 +32,8 @@ import {
 import type { ObjectEntity } from './ObjectEntity';
 import type { PatternNode } from './Pattern';
 
+type InteractionCalledArguments = NodeInteractionCalled['args'];
+
 export default abstract class FunctionBase extends NodeBase {
 	declare body: BlockStatement | ExpressionNode;
 	declare params: PatternNode[];
@@ -57,6 +64,27 @@ export default abstract class FunctionBase extends NodeBase {
 		this.flags = setFlag(this.flags, Flag.generator, value);
 	}
 
+	private updateParameterVariableValues(_arguments: InteractionCalledArguments): void {
+		for (let position = 0; position < this.params.length; position++) {
+			const parameter = this.params[position];
+			if (!(parameter instanceof Identifier)) {
+				continue;
+			}
+			const parameterVariable = parameter.variable as ParameterVariable;
+			const argument = _arguments[position + 1] ?? UNDEFINED_EXPRESSION;
+			parameterVariable.updateKnownValue(argument);
+		}
+	}
+
+	private deoptimizeParameterVariableValues() {
+		for (const parameter of this.params) {
+			if (parameter instanceof Identifier) {
+				const parameterVariable = parameter.variable as ParameterVariable;
+				parameterVariable.markReassigned();
+			}
+		}
+	}
+
 	protected objectEntity: ObjectEntity | null = null;
 
 	deoptimizeArgumentsOnInteractionAtPath(
@@ -84,6 +112,7 @@ export default abstract class FunctionBase extends NodeBase {
 					this.addArgumentToBeDeoptimized(argument);
 				}
 			}
+			this.updateParameterVariableValues(args);
 		} else {
 			this.getObjectEntity().deoptimizeArgumentsOnInteractionAtPath(
 				interaction,
@@ -102,6 +131,7 @@ export default abstract class FunctionBase extends NodeBase {
 			for (const parameterList of this.scope.parameters) {
 				for (const parameter of parameterList) {
 					parameter.deoptimizePath(UNKNOWN_PATH);
+					parameter.markReassigned();
 				}
 			}
 		}
@@ -180,7 +210,26 @@ export default abstract class FunctionBase extends NodeBase {
 		return false;
 	}
 
+	/**
+	 * If the function (expression or declaration) is only used as function calls
+	 */
+	protected onlyFunctionCallUsed(): boolean {
+		let variable: Variable | null = null;
+		if (this.parent.type === NodeType.VariableDeclarator) {
+			variable = (this.parent as VariableDeclarator).id.variable ?? null;
+		}
+		if (this.parent.type === NodeType.ExportDefaultDeclaration) {
+			variable = (this.parent as ExportDefaultDeclaration).variable;
+		}
+		return variable?.getOnlyFunctionCallUsed() ?? false;
+	}
+
+	private parameterVariableValuesDeoptimized = false;
 	include(context: InclusionContext, includeChildrenRecursively: IncludeChildren): void {
+		if (!this.parameterVariableValuesDeoptimized && !this.onlyFunctionCallUsed()) {
+			this.parameterVariableValuesDeoptimized = true;
+			this.deoptimizeParameterVariableValues();
+		}
 		if (!this.deoptimized) this.applyDeoptimizations();
 		this.included = true;
 		const { brokenFlow } = context;
diff --git a/src/ast/variables/ExportDefaultVariable.ts b/src/ast/variables/ExportDefaultVariable.ts
index 979405b5784..70810936e5a 100644
--- a/src/ast/variables/ExportDefaultVariable.ts
+++ b/src/ast/variables/ExportDefaultVariable.ts
@@ -3,6 +3,7 @@ import ClassDeclaration from '../nodes/ClassDeclaration';
 import type ExportDefaultDeclaration from '../nodes/ExportDefaultDeclaration';
 import FunctionDeclaration from '../nodes/FunctionDeclaration';
 import Identifier, { type IdentifierWithVariable } from '../nodes/Identifier';
+import type { NodeBase } from '../nodes/shared/Node';
 import LocalVariable from './LocalVariable';
 import UndefinedVariable from './UndefinedVariable';
 import type Variable from './Variable';
@@ -37,6 +38,15 @@ export default class ExportDefaultVariable extends LocalVariable {
 		}
 	}
 
+	addUsedPlace(usedPlace: NodeBase): void {
+		const original = this.getOriginalVariable();
+		if (original === this) {
+			super.addUsedPlace(usedPlace);
+		} else {
+			original.addUsedPlace(usedPlace);
+		}
+	}
+
 	forbidName(name: string) {
 		const original = this.getOriginalVariable();
 		if (original === this) {
diff --git a/src/ast/variables/GlobalVariable.ts b/src/ast/variables/GlobalVariable.ts
index d55ed63ae00..4f168ac8f86 100644
--- a/src/ast/variables/GlobalVariable.ts
+++ b/src/ast/variables/GlobalVariable.ts
@@ -13,9 +13,12 @@ import type { ObjectPath, PathTracker } from '../utils/PathTracker';
 import Variable from './Variable';
 
 export default class GlobalVariable extends Variable {
-	// Ensure we use live-bindings for globals as we do not know if they have
-	// been reassigned
-	isReassigned = true;
+	constructor(name: string) {
+		super(name);
+		// Ensure we use live-bindings for globals as we do not know if they have
+		// been reassigned
+		this.markReassigned();
+	}
 
 	deoptimizeArgumentsOnInteractionAtPath(
 		interaction: NodeInteraction,
diff --git a/src/ast/variables/LocalVariable.ts b/src/ast/variables/LocalVariable.ts
index fe5bd488492..83b32a81ef7 100644
--- a/src/ast/variables/LocalVariable.ts
+++ b/src/ast/variables/LocalVariable.ts
@@ -91,7 +91,7 @@ export default class LocalVariable extends Variable {
 			return;
 		}
 		if (path.length === 0) {
-			this.isReassigned = true;
+			this.markReassigned();
 			const expressionsToBeDeoptimized = this.expressionsToBeDeoptimized;
 			this.expressionsToBeDeoptimized = EMPTY_ARRAY as unknown as DeoptimizableEntity[];
 			for (const expression of expressionsToBeDeoptimized) {
@@ -222,7 +222,7 @@ export default class LocalVariable extends Variable {
 		if (this.additionalInitializers === null) {
 			this.additionalInitializers = [this.init];
 			this.init = UNKNOWN_EXPRESSION;
-			this.isReassigned = true;
+			this.markReassigned();
 		}
 		return this.additionalInitializers;
 	}
diff --git a/src/ast/variables/ParameterVariable.ts b/src/ast/variables/ParameterVariable.ts
index 94f3feb90d9..a17bf3b1152 100644
--- a/src/ast/variables/ParameterVariable.ts
+++ b/src/ast/variables/ParameterVariable.ts
@@ -1,17 +1,21 @@
 import type { AstContext } from '../../Module';
 import { EMPTY_ARRAY } from '../../utils/blank';
+import type { DeoptimizableEntity } from '../DeoptimizableEntity';
+import type { HasEffectsContext } from '../ExecutionContext';
 import type { NodeInteraction } from '../NodeInteractions';
-import { INTERACTION_CALLED } from '../NodeInteractions';
+import { INTERACTION_ASSIGNED, INTERACTION_CALLED } from '../NodeInteractions';
 import type ExportDefaultDeclaration from '../nodes/ExportDefaultDeclaration';
-import type Identifier from '../nodes/Identifier';
-import type { ExpressionEntity } from '../nodes/shared/Expression';
+import Identifier from '../nodes/Identifier';
+import type { ExpressionEntity, LiteralValueOrUnknown } from '../nodes/shared/Expression';
 import {
 	deoptimizeInteraction,
 	UNKNOWN_EXPRESSION,
-	UNKNOWN_RETURN_EXPRESSION
+	UNKNOWN_RETURN_EXPRESSION,
+	UnknownValue
 } from '../nodes/shared/Expression';
 import type { ObjectPath, ObjectPathKey } from '../utils/PathTracker';
 import {
+	EMPTY_PATH,
 	PathTracker,
 	SHARED_RECURSION_TRACKER,
 	UNKNOWN_PATH,
@@ -35,6 +39,7 @@ export default class ParameterVariable extends LocalVariable {
 	private deoptimizations = new PathTracker();
 	private deoptimizedFields = new Set<ObjectPathKey>();
 	private entitiesToBeDeoptimized = new Set<ExpressionEntity>();
+	private expressionsUseTheKnownValue: DeoptimizableEntity[] = [];
 
 	constructor(
 		name: string,
@@ -71,6 +76,110 @@ export default class ParameterVariable extends LocalVariable {
 		}
 	}
 
+	markReassigned(): void {
+		if (this.isReassigned) {
+			return;
+		}
+		super.markReassigned();
+		for (const expression of this.expressionsUseTheKnownValue) {
+			expression.deoptimizeCache();
+		}
+		this.expressionsUseTheKnownValue = EMPTY_ARRAY as unknown as DeoptimizableEntity[];
+	}
+
+	deoptimizeCache(): void {
+		this.markReassigned();
+	}
+
+	private knownValue: ExpressionEntity | null = null;
+	private knownValueLiteral: LiteralValueOrUnknown = UnknownValue;
+	/**
+	 * Update the known value of the parameter variable.
+	 * Must be called for every function call, so it can track all the arguments,
+	 * and deoptimizeCache itself to mark reassigned if the argument is changed.
+	 * @param argument The argument of the function call
+	 */
+	updateKnownValue(argument: ExpressionEntity) {
+		if (this.isReassigned) {
+			return;
+		}
+
+		if (this.knownValue === null) {
+			this.knownValue = argument;
+			this.knownValueLiteral = argument.getLiteralValueAtPath(
+				EMPTY_PATH,
+				SHARED_RECURSION_TRACKER,
+				this
+			);
+			return;
+		}
+
+		// the same literal or identifier, do nothing
+		if (
+			this.knownValue === argument ||
+			(this.knownValue instanceof Identifier &&
+				argument instanceof Identifier &&
+				this.knownValue.variable === argument.variable)
+		) {
+			return;
+		}
+
+		const oldValue = this.knownValueLiteral;
+		if (typeof oldValue === 'symbol') {
+			this.markReassigned();
+			return;
+		}
+		// add tracking for the new argument
+		const newValue = argument.getLiteralValueAtPath(EMPTY_PATH, SHARED_RECURSION_TRACKER, this);
+		if (newValue !== oldValue) {
+			this.markReassigned();
+		}
+	}
+
+	private frozenValue: ExpressionEntity | null = null;
+	/**
+	 * This function freezes the known value of the parameter variable,
+	 * so the optimization starts with a certain ExpressionEntity.
+	 * The optimization can be undone by calling `markReassigned`.
+	 * @returns the frozen value
+	 */
+	private getKnownValue(): ExpressionEntity {
+		if (this.frozenValue === null) {
+			this.frozenValue = this.knownValue || UNKNOWN_EXPRESSION;
+		}
+		return this.frozenValue;
+	}
+
+	getLiteralValueAtPath(
+		path: ObjectPath,
+		recursionTracker: PathTracker,
+		origin: DeoptimizableEntity
+	): LiteralValueOrUnknown {
+		if (this.isReassigned) {
+			return UnknownValue;
+		}
+		const knownValue = this.getKnownValue();
+		this.expressionsUseTheKnownValue.push(origin);
+		return recursionTracker.withTrackedEntityAtPath(
+			path,
+			knownValue,
+			() => knownValue.getLiteralValueAtPath(path, recursionTracker, origin),
+			UnknownValue
+		);
+	}
+
+	hasEffectsOnInteractionAtPath(
+		path: ObjectPath,
+		interaction: NodeInteraction,
+		context: HasEffectsContext
+	): boolean {
+		if (this.isReassigned || interaction.type === INTERACTION_ASSIGNED) {
+			return super.hasEffectsOnInteractionAtPath(path, interaction, context);
+		}
+		const knownValue = this.getKnownValue();
+		return knownValue.hasEffectsOnInteractionAtPath(path, interaction, context);
+	}
+
 	deoptimizeArgumentsOnInteractionAtPath(interaction: NodeInteraction, path: ObjectPath): void {
 		// For performance reasons, we fully deoptimize all deeper interactions
 		if (
@@ -98,7 +207,11 @@ export default class ParameterVariable extends LocalVariable {
 	}
 
 	deoptimizePath(path: ObjectPath): void {
-		if (path.length === 0 || this.deoptimizedFields.has(UnknownKey)) {
+		if (path.length === 0) {
+			this.markReassigned();
+			return;
+		}
+		if (this.deoptimizedFields.has(UnknownKey)) {
 			return;
 		}
 		const key = path[0];
diff --git a/src/ast/variables/Variable.ts b/src/ast/variables/Variable.ts
index 521ff1f9b71..0cd2e40dddb 100644
--- a/src/ast/variables/Variable.ts
+++ b/src/ast/variables/Variable.ts
@@ -4,8 +4,11 @@ import type { RenderOptions } from '../../utils/renderHelpers';
 import type { HasEffectsContext } from '../ExecutionContext';
 import type { NodeInteraction } from '../NodeInteractions';
 import { INTERACTION_ACCESSED } from '../NodeInteractions';
+import type CallExpression from '../nodes/CallExpression';
 import type Identifier from '../nodes/Identifier';
+import * as NodeType from '../nodes/NodeType';
 import { ExpressionEntity } from '../nodes/shared/Expression';
+import type { NodeBase } from '../nodes/shared/Node';
 import type { VariableKind } from '../nodes/shared/VariableKinds';
 import type { ObjectPath } from '../utils/PathTracker';
 
@@ -16,7 +19,6 @@ export default class Variable extends ExpressionEntity {
 	isId = false;
 	// both NamespaceVariable and ExternalVariable can be namespaces
 	declare isNamespace?: boolean;
-	isReassigned = false;
 	kind: VariableKind | null = null;
 	declare module?: Module | ExternalModule;
 	renderBaseName: string | null = null;
@@ -24,6 +26,11 @@ export default class Variable extends ExpressionEntity {
 
 	private renderedLikeHoisted?: Variable;
 
+	readonly isReassigned = false;
+	markReassigned() {
+		(this as { isReassigned: boolean }).isReassigned = true;
+	}
+
 	constructor(public name: string) {
 		super();
 	}
@@ -34,6 +41,28 @@ export default class Variable extends ExpressionEntity {
 	 */
 	addReference(_identifier: Identifier): void {}
 
+	private onlyFunctionCallUsed = true;
+	/**
+	 * Check if the identifier variable is only used as function call
+	 * @returns true if the variable is only used as function call
+	 */
+	getOnlyFunctionCallUsed(): boolean {
+		return this.onlyFunctionCallUsed;
+	}
+
+	/**
+	 * Collect the places where the identifier variable is used
+	 * @param usedPlace Where the variable is used
+	 */
+	addUsedPlace(usedPlace: NodeBase): void {
+		const isFunctionCall =
+			usedPlace.parent.type === NodeType.CallExpression &&
+			(usedPlace.parent as CallExpression).callee === usedPlace;
+		if (!isFunctionCall && usedPlace.parent.type !== NodeType.ExportDefaultDeclaration) {
+			this.onlyFunctionCallUsed = false;
+		}
+	}
+
 	/**
 	 * Prevent this variable from being renamed to this name to avoid name
 	 * collisions
diff --git a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/amd/dep1.js b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/amd/dep1.js
index 1ebb9552c37..c0bb33a6273 100644
--- a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/amd/dep1.js
+++ b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/amd/dep1.js
@@ -5,12 +5,13 @@ define(['exports'], (function (exports) { 'use strict';
 	console.log('This is the output when a missing export is used internally but not reexported');
 
 	function almostUseUnused(useIt) {
-		if (useIt) {
+		{
+			console.log(useIt);
 			console.log(_missingExportShim);
 		}
 	}
 
-	almostUseUnused(false);
+	almostUseUnused(true);
 
 	exports.missing1 = _missingExportShim;
 
diff --git a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/cjs/dep1.js b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/cjs/dep1.js
index a024bcd6f7f..31b08b56a1f 100644
--- a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/cjs/dep1.js
+++ b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/cjs/dep1.js
@@ -5,11 +5,12 @@ var _missingExportShim = void 0;
 console.log('This is the output when a missing export is used internally but not reexported');
 
 function almostUseUnused(useIt) {
-	if (useIt) {
+	{
+		console.log(useIt);
 		console.log(_missingExportShim);
 	}
 }
 
-almostUseUnused(false);
+almostUseUnused(true);
 
 exports.missing1 = _missingExportShim;
diff --git a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/es/dep1.js b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/es/dep1.js
index 99f4196bf72..d9c8b65f05c 100644
--- a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/es/dep1.js
+++ b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/es/dep1.js
@@ -3,11 +3,12 @@ var _missingExportShim = void 0;
 console.log('This is the output when a missing export is used internally but not reexported');
 
 function almostUseUnused(useIt) {
-	if (useIt) {
+	{
+		console.log(useIt);
 		console.log(_missingExportShim);
 	}
 }
 
-almostUseUnused(false);
+almostUseUnused(true);
 
 export { _missingExportShim as missing1 };
diff --git a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/system/dep1.js b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/system/dep1.js
index fb77b0059b6..24aa7ab54ea 100644
--- a/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/system/dep1.js
+++ b/test/chunking-form/samples/missing-export-reused-deconflicting/_expected/system/dep1.js
@@ -8,12 +8,13 @@ System.register([], (function (exports) {
 			console.log('This is the output when a missing export is used internally but not reexported');
 
 			function almostUseUnused(useIt) {
-				if (useIt) {
+				{
+					console.log(useIt);
 					console.log(_missingExportShim);
 				}
 			}
 
-			almostUseUnused(false);
+			almostUseUnused(true);
 
 			exports("missing1", _missingExportShim);
 
diff --git a/test/chunking-form/samples/missing-export-reused-deconflicting/dep1.js b/test/chunking-form/samples/missing-export-reused-deconflicting/dep1.js
index 84e22e0fe8f..f0751ef4cf6 100644
--- a/test/chunking-form/samples/missing-export-reused-deconflicting/dep1.js
+++ b/test/chunking-form/samples/missing-export-reused-deconflicting/dep1.js
@@ -2,8 +2,9 @@ console.log('This is the output when a missing export is used internally but not
 
 function almostUseUnused(useIt) {
 	if (useIt) {
+		console.log(useIt);
 		console.log(_missingExportShim);
 	}
 }
 
-almostUseUnused(false);
+almostUseUnused(true);
diff --git a/test/chunking-form/samples/preserve-modules-commonjs/_expected/amd/_virtual/_commonjsHelpers.js b/test/chunking-form/samples/preserve-modules-commonjs/_expected/amd/_virtual/_commonjsHelpers.js
index f35ac4ef0d7..25ed6cf3721 100644
--- a/test/chunking-form/samples/preserve-modules-commonjs/_expected/amd/_virtual/_commonjsHelpers.js
+++ b/test/chunking-form/samples/preserve-modules-commonjs/_expected/amd/_virtual/_commonjsHelpers.js
@@ -1,7 +1,7 @@
 define(['exports'], (function (exports) { 'use strict';
 
 	function getDefaultExportFromCjs (x) {
-		return x && x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
+		return x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
 	}
 
 	exports.getDefaultExportFromCjs = getDefaultExportFromCjs;
diff --git a/test/chunking-form/samples/preserve-modules-commonjs/_expected/cjs/_virtual/_commonjsHelpers.js b/test/chunking-form/samples/preserve-modules-commonjs/_expected/cjs/_virtual/_commonjsHelpers.js
index ceeaa4d077f..fc314aed4db 100644
--- a/test/chunking-form/samples/preserve-modules-commonjs/_expected/cjs/_virtual/_commonjsHelpers.js
+++ b/test/chunking-form/samples/preserve-modules-commonjs/_expected/cjs/_virtual/_commonjsHelpers.js
@@ -1,7 +1,7 @@
 'use strict';
 
 function getDefaultExportFromCjs (x) {
-	return x && x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
+	return x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
 }
 
 exports.getDefaultExportFromCjs = getDefaultExportFromCjs;
diff --git a/test/chunking-form/samples/preserve-modules-commonjs/_expected/es/_virtual/_commonjsHelpers.js b/test/chunking-form/samples/preserve-modules-commonjs/_expected/es/_virtual/_commonjsHelpers.js
index 7b7c5f4f531..5fea8b90999 100644
--- a/test/chunking-form/samples/preserve-modules-commonjs/_expected/es/_virtual/_commonjsHelpers.js
+++ b/test/chunking-form/samples/preserve-modules-commonjs/_expected/es/_virtual/_commonjsHelpers.js
@@ -1,5 +1,5 @@
 function getDefaultExportFromCjs (x) {
-	return x && x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
+	return x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
 }
 
 export { getDefaultExportFromCjs };
diff --git a/test/chunking-form/samples/preserve-modules-commonjs/_expected/system/_virtual/_commonjsHelpers.js b/test/chunking-form/samples/preserve-modules-commonjs/_expected/system/_virtual/_commonjsHelpers.js
index dd2c5886a6d..15f3676f92e 100644
--- a/test/chunking-form/samples/preserve-modules-commonjs/_expected/system/_virtual/_commonjsHelpers.js
+++ b/test/chunking-form/samples/preserve-modules-commonjs/_expected/system/_virtual/_commonjsHelpers.js
@@ -6,7 +6,7 @@ System.register([], (function (exports) {
 			exports("getDefaultExportFromCjs", getDefaultExportFromCjs);
 
 			function getDefaultExportFromCjs (x) {
-				return x && x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
+				return x.__esModule && Object.prototype.hasOwnProperty.call(x, 'default') ? x['default'] : x;
 			}
 
 		})
diff --git a/test/form/samples/deopt-string-concatenation/_expected.js b/test/form/samples/deopt-string-concatenation/_expected.js
index 68a30dc4f66..42785de7340 100644
--- a/test/form/samples/deopt-string-concatenation/_expected.js
+++ b/test/form/samples/deopt-string-concatenation/_expected.js
@@ -9,3 +9,4 @@ function parseInt(str, radix) {
 }
 
 console.log(parseInt('1'));
+console.log(parseInt(Symbol('1')));
diff --git a/test/form/samples/deopt-string-concatenation/main.js b/test/form/samples/deopt-string-concatenation/main.js
index 68a30dc4f66..42785de7340 100644
--- a/test/form/samples/deopt-string-concatenation/main.js
+++ b/test/form/samples/deopt-string-concatenation/main.js
@@ -9,3 +9,4 @@ function parseInt(str, radix) {
 }
 
 console.log(parseInt('1'));
+console.log(parseInt(Symbol('1')));
diff --git a/test/form/samples/request-tree-shaking-before-render/_config.js b/test/form/samples/request-tree-shaking-before-render/_config.js
new file mode 100644
index 00000000000..00d3b4e069f
--- /dev/null
+++ b/test/form/samples/request-tree-shaking-before-render/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'a new tree-shaking is required so render will not fail'
+});
diff --git a/test/form/samples/request-tree-shaking-before-render/_expected.js b/test/form/samples/request-tree-shaking-before-render/_expected.js
new file mode 100644
index 00000000000..f026827564f
--- /dev/null
+++ b/test/form/samples/request-tree-shaking-before-render/_expected.js
@@ -0,0 +1,16 @@
+function s(t) {
+    t(x);
+}
+
+function f(b) {
+    return x.concat((b ? 1 : 0))
+}
+
+function w(b) {
+    f(b);
+}
+
+w(1);
+s(() => {
+  return w(0)
+});
diff --git a/test/form/samples/request-tree-shaking-before-render/main.js b/test/form/samples/request-tree-shaking-before-render/main.js
new file mode 100644
index 00000000000..85b8d493594
--- /dev/null
+++ b/test/form/samples/request-tree-shaking-before-render/main.js
@@ -0,0 +1,16 @@
+function s(t) {
+    t(x)
+}
+
+function f(b) {
+    return x.concat((b ? 1 : 0))
+}
+
+function w(b) {
+    f(b)
+}
+
+w(1)
+s(() => {
+  return w(0)
+})
diff --git a/test/form/samples/side-effect-h/_expected/amd.js b/test/form/samples/side-effect-h/_expected/amd.js
index d3a055b343a..e46b7cd7cb9 100644
--- a/test/form/samples/side-effect-h/_expected/amd.js
+++ b/test/form/samples/side-effect-h/_expected/amd.js
@@ -7,6 +7,7 @@ define((function () { 'use strict';
 	}
 
 	foo();
+	foo(true);
 
 	var main = 42;
 
diff --git a/test/form/samples/side-effect-h/_expected/cjs.js b/test/form/samples/side-effect-h/_expected/cjs.js
index 1d437295c93..4862e7aa0e7 100644
--- a/test/form/samples/side-effect-h/_expected/cjs.js
+++ b/test/form/samples/side-effect-h/_expected/cjs.js
@@ -7,6 +7,7 @@ function foo ( ok ) {
 }
 
 foo();
+foo(true);
 
 var main = 42;
 
diff --git a/test/form/samples/side-effect-h/_expected/es.js b/test/form/samples/side-effect-h/_expected/es.js
index 1d5410d073d..39c215e330c 100644
--- a/test/form/samples/side-effect-h/_expected/es.js
+++ b/test/form/samples/side-effect-h/_expected/es.js
@@ -5,6 +5,7 @@ function foo ( ok ) {
 }
 
 foo();
+foo(true);
 
 var main = 42;
 
diff --git a/test/form/samples/side-effect-h/_expected/iife.js b/test/form/samples/side-effect-h/_expected/iife.js
index 083d37914dd..b6fc61fb49b 100644
--- a/test/form/samples/side-effect-h/_expected/iife.js
+++ b/test/form/samples/side-effect-h/_expected/iife.js
@@ -8,6 +8,7 @@ var myBundle = (function () {
 	}
 
 	foo();
+	foo(true);
 
 	var main = 42;
 
diff --git a/test/form/samples/side-effect-h/_expected/system.js b/test/form/samples/side-effect-h/_expected/system.js
index dcb761aa7ba..6ace3fb0f81 100644
--- a/test/form/samples/side-effect-h/_expected/system.js
+++ b/test/form/samples/side-effect-h/_expected/system.js
@@ -10,6 +10,7 @@ System.register('myBundle', [], (function (exports) {
 			}
 
 			foo();
+			foo(true);
 
 			var main = exports("default", 42);
 
diff --git a/test/form/samples/side-effect-h/_expected/umd.js b/test/form/samples/side-effect-h/_expected/umd.js
index 770859846a0..f72ccce31f6 100644
--- a/test/form/samples/side-effect-h/_expected/umd.js
+++ b/test/form/samples/side-effect-h/_expected/umd.js
@@ -11,6 +11,7 @@
 	}
 
 	foo();
+	foo(true);
 
 	var main = 42;
 
diff --git a/test/form/samples/side-effect-h/main.js b/test/form/samples/side-effect-h/main.js
index 16d73469124..b736c13f944 100644
--- a/test/form/samples/side-effect-h/main.js
+++ b/test/form/samples/side-effect-h/main.js
@@ -5,5 +5,6 @@ function foo ( ok ) {
 }
 
 foo();
+foo(true);
 
 export default 42;
diff --git a/test/form/samples/side-effects-return-statements/_expected/amd.js b/test/form/samples/side-effects-return-statements/_expected/amd.js
index dcdb995d37a..1633b0ab0e9 100644
--- a/test/form/samples/side-effects-return-statements/_expected/amd.js
+++ b/test/form/samples/side-effects-return-statements/_expected/amd.js
@@ -8,5 +8,6 @@ define((function () { 'use strict';
 	}
 
 	assert.equal( isUsed( true ), 2 );
+	assert.equal( isUsed( false ), 1 );
 
 }));
diff --git a/test/form/samples/side-effects-return-statements/_expected/cjs.js b/test/form/samples/side-effects-return-statements/_expected/cjs.js
index 7dd6e813034..93d4ccf36c7 100644
--- a/test/form/samples/side-effects-return-statements/_expected/cjs.js
+++ b/test/form/samples/side-effects-return-statements/_expected/cjs.js
@@ -8,3 +8,4 @@ function isUsed ( x ) {
 }
 
 assert.equal( isUsed( true ), 2 );
+assert.equal( isUsed( false ), 1 );
diff --git a/test/form/samples/side-effects-return-statements/_expected/es.js b/test/form/samples/side-effects-return-statements/_expected/es.js
index 38f357c97fc..9898b0d0f8b 100644
--- a/test/form/samples/side-effects-return-statements/_expected/es.js
+++ b/test/form/samples/side-effects-return-statements/_expected/es.js
@@ -6,3 +6,4 @@ function isUsed ( x ) {
 }
 
 assert.equal( isUsed( true ), 2 );
+assert.equal( isUsed( false ), 1 );
diff --git a/test/form/samples/side-effects-return-statements/_expected/iife.js b/test/form/samples/side-effects-return-statements/_expected/iife.js
index c9da6fbbcd3..81b64ec8112 100644
--- a/test/form/samples/side-effects-return-statements/_expected/iife.js
+++ b/test/form/samples/side-effects-return-statements/_expected/iife.js
@@ -9,5 +9,6 @@
 	}
 
 	assert.equal( isUsed( true ), 2 );
+	assert.equal( isUsed( false ), 1 );
 
 })();
diff --git a/test/form/samples/side-effects-return-statements/_expected/system.js b/test/form/samples/side-effects-return-statements/_expected/system.js
index 968b341638b..096bcc73f08 100644
--- a/test/form/samples/side-effects-return-statements/_expected/system.js
+++ b/test/form/samples/side-effects-return-statements/_expected/system.js
@@ -11,6 +11,7 @@ System.register('myBundle', [], (function () {
 			}
 
 			assert.equal( isUsed( true ), 2 );
+			assert.equal( isUsed( false ), 1 );
 
 		})
 	};
diff --git a/test/form/samples/side-effects-return-statements/_expected/umd.js b/test/form/samples/side-effects-return-statements/_expected/umd.js
index 97a5be31699..fc3ff304af8 100644
--- a/test/form/samples/side-effects-return-statements/_expected/umd.js
+++ b/test/form/samples/side-effects-return-statements/_expected/umd.js
@@ -11,5 +11,6 @@
 	}
 
 	assert.equal( isUsed( true ), 2 );
+	assert.equal( isUsed( false ), 1 );
 
 }));
diff --git a/test/form/samples/side-effects-return-statements/main.js b/test/form/samples/side-effects-return-statements/main.js
index 8e6b3b54f4f..a1e68e5d63f 100644
--- a/test/form/samples/side-effects-return-statements/main.js
+++ b/test/form/samples/side-effects-return-statements/main.js
@@ -15,3 +15,4 @@ function isUsed ( x ) {
 }
 
 assert.equal( isUsed( true ), 2 );
+assert.equal( isUsed( false ), 1 );
diff --git a/test/form/samples/supports-es5-shim/_expected.js b/test/form/samples/supports-es5-shim/_expected.js
index bc68debf94b..645169277b6 100644
--- a/test/form/samples/supports-es5-shim/_expected.js
+++ b/test/form/samples/supports-es5-shim/_expected.js
@@ -2202,7 +2202,6 @@ var es5Shim = {exports: {}};
 	        // eslint-disable-next-line no-global-assign, no-implicit-globals
 	        parseInt = (function (origParseInt) {
 	            return function parseInt(str, radix) {
-	                if (this instanceof parseInt) { new origParseInt(); } // eslint-disable-line new-cap, no-new, max-statements-per-line
 	                var string = trim(String(str));
 	                var defaultedRadix = $Number(radix) || (hexRegex.test(string) ? 16 : 10);
 	                return origParseInt(string, defaultedRadix);
@@ -2233,7 +2232,6 @@ var es5Shim = {exports: {}};
 	        // eslint-disable-next-line no-global-assign, no-implicit-globals
 	        parseInt = (function (origParseInt) {
 	            return function parseInt(str, radix) {
-	                if (this instanceof parseInt) { new origParseInt(); } // eslint-disable-line new-cap, no-new, max-statements-per-line
 	                var isSym = typeof str === 'symbol';
 	                if (!isSym && str && typeof str === 'object') {
 	                    try {
diff --git a/test/form/samples/supports-es6-shim/_expected.js b/test/form/samples/supports-es6-shim/_expected.js
index ae2951820eb..84fb3b7f09d 100644
--- a/test/form/samples/supports-es6-shim/_expected.js
+++ b/test/form/samples/supports-es6-shim/_expected.js
@@ -2057,7 +2057,7 @@ var es6Shim = {exports: {}};
 	  };
 
 	  var withinULPDistance = function withinULPDistance(result, expected, distance) {
-	    return _abs(1 - (result / expected)) / Number.EPSILON < (distance || 8);
+	    return _abs(1 - (result / expected)) / Number.EPSILON < (8);
 	  };
 
 	  defineProperties(Math, MathShims);
diff --git a/test/form/samples/tree-shake-literal-parameter/argument-assignment/_config.js b/test/form/samples/tree-shake-literal-parameter/argument-assignment/_config.js
new file mode 100644
index 00000000000..1a210baea05
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/argument-assignment/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'argument assignment side-effect'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/argument-assignment/_expected.js b/test/form/samples/tree-shake-literal-parameter/argument-assignment/_expected.js
new file mode 100644
index 00000000000..f7cb2c16d5a
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/argument-assignment/_expected.js
@@ -0,0 +1,15 @@
+function add(a, b) {
+	let sum = 0;
+	for (let i = a; i < b; i++) {
+		sum += i;
+	}
+	return sum;
+}
+
+function foo(a) {
+	// don't optimize to '0;'
+	a = 0;
+	console.log(a);
+}
+
+console.log(foo(add(0, 100)));
diff --git a/test/form/samples/tree-shake-literal-parameter/argument-assignment/main.js b/test/form/samples/tree-shake-literal-parameter/argument-assignment/main.js
new file mode 100644
index 00000000000..d9b3646538f
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/argument-assignment/main.js
@@ -0,0 +1,15 @@
+function add(a, b) {
+	let sum = 0;
+	for (let i = a; i < b; i++) {
+		sum += i;
+	}
+	return sum;
+}
+
+function foo(a) {
+	// don't optimize to '0;'
+	a = 0;
+	console.log(a)
+}
+
+console.log(foo(add(0, 100)))
diff --git a/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_config.js b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_config.js
new file mode 100644
index 00000000000..d16519b0931
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'do not tree-shake literal parameter cases'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_expected.js b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_expected.js
new file mode 100644
index 00000000000..8e1230c7540
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/_expected.js
@@ -0,0 +1,18 @@
+function foo(enable) {
+	console.log(enable ? 1 : 0);
+}
+
+foo(1);
+
+function bar(f = foo) {
+	f(0);
+}
+
+// global variable
+g = function (enable) {
+	console.log(enable ? 1: 0);
+};
+
+g(1);
+
+export { bar };
diff --git a/test/form/samples/tree-shake-literal-parameter/do-not-optimize/main.js b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/main.js
new file mode 100644
index 00000000000..079d60a1be5
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/do-not-optimize/main.js
@@ -0,0 +1,16 @@
+function foo(enable) {
+	console.log(enable ? 1 : 0);
+}
+
+foo(1);
+
+export function bar(f = foo) {
+	f(0);
+}
+
+// global variable
+g = function (enable) {
+	console.log(enable ? 1: 0);
+};
+
+g(1);
diff --git a/test/form/samples/tree-shake-literal-parameter/expression-cache/_config.js b/test/form/samples/tree-shake-literal-parameter/expression-cache/_config.js
new file mode 100644
index 00000000000..697aea54b46
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/expression-cache/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'should update cache of logical and conditional expressions'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/expression-cache/_expected.js b/test/form/samples/tree-shake-literal-parameter/expression-cache/_expected.js
new file mode 100644
index 00000000000..8cee561823a
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/expression-cache/_expected.js
@@ -0,0 +1,14 @@
+function add1(a, b, enable) {
+	{
+		return a + b;
+	}
+}
+
+function add2(a, b, enable) {
+	{
+		return a + b;
+	}
+}
+
+console.log(add1(1, 2));
+console.log(add2(1, 2));
diff --git a/test/form/samples/tree-shake-literal-parameter/expression-cache/main.js b/test/form/samples/tree-shake-literal-parameter/expression-cache/main.js
new file mode 100644
index 00000000000..4c1f739a1d5
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/expression-cache/main.js
@@ -0,0 +1,16 @@
+function add1(a, b, enable) {
+	if (enable? true: false) {
+		return a + b;
+	}
+	return a - b;
+}
+
+function add2(a, b, enable) {
+	if (enable && 1) {
+		return a + b;
+	}
+	return a - b;
+}
+
+console.log(add1(1, 2, true));
+console.log(add2(1, 2, true));
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/iife/_config.js b/test/form/samples/tree-shake-literal-parameter/iife/_config.js
new file mode 100644
index 00000000000..789458177ac
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/iife/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'tree-shake literal parameter for IIFE'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/iife/_expected.js b/test/form/samples/tree-shake-literal-parameter/iife/_expected.js
new file mode 100644
index 00000000000..3e6eaeced15
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/iife/_expected.js
@@ -0,0 +1,32 @@
+const result1 = ((enable) => {
+	{
+		return 'enabled';
+	}
+})();
+
+const result2 = (function (enable) {
+	{
+		return 'enabled';
+	}
+})();
+
+const result3 = (function foo (enable) {
+	{
+		return 'enabled';
+	}
+})();
+
+// lose track of iife
+const result4 = (function foo (enable) {
+	if (enable) {
+		unknown_global_function(foo);
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+})(true);
+
+console.log(result1);
+console.log(result2);
+console.log(result3);
+console.log(result4);
diff --git a/test/form/samples/tree-shake-literal-parameter/iife/main.js b/test/form/samples/tree-shake-literal-parameter/iife/main.js
new file mode 100644
index 00000000000..844a193c3ff
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/iife/main.js
@@ -0,0 +1,38 @@
+const result1 = ((enable) => {
+	if (enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+})(true);
+
+const result2 = (function (enable) {
+	if (enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+})(true);
+
+const result3 = (function foo (enable) {
+	if (enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+})(true);
+
+// lose track of iife
+const result4 = (function foo (enable) {
+	if (enable) {
+		unknown_global_function(foo);
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+})(true);
+
+console.log(result1);
+console.log(result2);
+console.log(result3);
+console.log(result4);
diff --git a/test/form/samples/tree-shake-literal-parameter/import-function/_config.js b/test/form/samples/tree-shake-literal-parameter/import-function/_config.js
new file mode 100644
index 00000000000..e4a54b5f90f
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/import-function/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'set parameters to literal if all calls are literal'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/import-function/_expected.js b/test/form/samples/tree-shake-literal-parameter/import-function/_expected.js
new file mode 100644
index 00000000000..f9d8a0fd937
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/import-function/_expected.js
@@ -0,0 +1,70 @@
+// export default
+function add (a, b, enable) {
+	{
+		return a + b;
+	}
+}
+
+function add1(a, b, enable) {
+	return a - b;
+}
+
+function add2(a, b, enable) {
+	return a - b;
+}
+
+// keep it
+function add3(a, b, enable) {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+// conditional expression
+function add4(a, b, enable) {
+	{
+		return a + b;
+	}
+}
+
+// export default
+var arrowAdd = (a, b, enable) => {
+	{
+		return a + b;
+	}
+};
+
+const arrowAdd1 = (a, b, enable) => {
+	return a - b;
+};
+
+// keep it
+const arrowAdd2 = (a, b, enable) => {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+};
+
+// conditional expression
+const arrowAdd3 = (a, b, enable) => {
+	{
+		return a + b;
+	}
+};
+
+function foo(bar) {
+	console.log(bar());
+}
+
+console.log(add(1, 2));
+console.log(add1(1, 2));
+console.log(add2(1, 2)); // unused argument should be treated as undefined
+console.log(foo(add3));
+console.log(add4(1, 2));
+
+console.log(arrowAdd(1, 2));
+console.log(arrowAdd1(1, 2));
+console.log(foo(arrowAdd2));
+console.log(arrowAdd3(1, 2));
diff --git a/test/form/samples/tree-shake-literal-parameter/import-function/arrow_lib.js b/test/form/samples/tree-shake-literal-parameter/import-function/arrow_lib.js
new file mode 100644
index 00000000000..8b85efc44a7
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/import-function/arrow_lib.js
@@ -0,0 +1,30 @@
+// export default
+export default (a, b, enable) => {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+export const arrowAdd1 = (a, b, enable) => {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+// keep it
+export const arrowAdd2 = (a, b, enable) => {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+// conditional expression
+export const arrowAdd3 = (a, b, enable) => {
+	if (enable? true: false) {
+		return a + b;
+	}
+	return a - b;
+}
diff --git a/test/form/samples/tree-shake-literal-parameter/import-function/lib.js b/test/form/samples/tree-shake-literal-parameter/import-function/lib.js
new file mode 100644
index 00000000000..be4b8a63c76
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/import-function/lib.js
@@ -0,0 +1,37 @@
+// export default
+export default function (a, b, enable) {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+export function add1(a, b, enable) {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+export function add2(a, b, enable) {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+// keep it
+export function add3(a, b, enable) {
+	if (enable) {
+		return a + b;
+	}
+	return a - b;
+}
+
+// conditional expression
+export function add4(a, b, enable) {
+	if (enable? true: false) {
+		return a + b;
+	}
+	return a - b;
+}
diff --git a/test/form/samples/tree-shake-literal-parameter/import-function/main.js b/test/form/samples/tree-shake-literal-parameter/import-function/main.js
new file mode 100644
index 00000000000..fcd0b9dcbe1
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/import-function/main.js
@@ -0,0 +1,17 @@
+import add, { add1, add2, add3, add4 } from './lib.js'
+import arrowAdd, { arrowAdd1, arrowAdd2, arrowAdd3 } from './arrow_lib.js'
+
+function foo(bar) {
+	console.log(bar());
+}
+
+console.log(add(1, 2, true));
+console.log(add1(1, 2, false));
+console.log(add2(1, 2)); // unused argument should be treated as undefined
+console.log(foo(add3))
+console.log(add4(1, 2, true));
+
+console.log(arrowAdd(1, 2, true));
+console.log(arrowAdd1(1, 2, false));
+console.log(foo(arrowAdd2));
+console.log(arrowAdd3(1, 2, true));
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_config.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_config.js
new file mode 100644
index 00000000000..43454f74be2
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'parameters of indirect function import should also be tree-shaken'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_expected.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_expected.js
new file mode 100644
index 00000000000..39872a4cff7
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/_expected.js
@@ -0,0 +1,14 @@
+function importThenExportSub(enable) {
+	{
+		return 'importThenExportSub';
+	}
+}
+
+function defineAndExportDefault(enable) {
+	{
+		return 'defineAndExportDefault';
+	}
+}
+
+console.log(importThenExportSub());
+console.log(defineAndExportDefault());
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/define_and_export_default.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/define_and_export_default.js
new file mode 100644
index 00000000000..b52e1846d0f
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/define_and_export_default.js
@@ -0,0 +1,7 @@
+function defineAndExportDefault(enable) {
+	if (enable) {
+		return 'defineAndExportDefault';
+	}
+}
+
+export default defineAndExportDefault;
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export.js
new file mode 100644
index 00000000000..30e7e2b911d
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export.js
@@ -0,0 +1,3 @@
+import { importThenExportSub } from './import_then_export_sub.js'
+
+export { importThenExportSub }
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export_sub.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export_sub.js
new file mode 100644
index 00000000000..2afc494681e
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/import_then_export_sub.js
@@ -0,0 +1,5 @@
+export function importThenExportSub(enable) {
+	if (enable) {
+		return 'importThenExportSub';
+	}
+}
diff --git a/test/form/samples/tree-shake-literal-parameter/indirect-import-function/main.js b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/main.js
new file mode 100644
index 00000000000..ad0e9fb2639
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/indirect-import-function/main.js
@@ -0,0 +1,5 @@
+import { importThenExportSub } from './import_then_export.js'
+import defineAndExportDefault from './define_and_export_default.js'
+
+console.log(importThenExportSub(true))
+console.log(defineAndExportDefault(true))
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_config.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_config.js
new file mode 100644
index 00000000000..251df7a6a12
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'function parameters tree-shaken should be recursive if literal'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_expected.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_expected.js
new file mode 100644
index 00000000000..f909ce360ec
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/_expected.js
@@ -0,0 +1,22 @@
+function fun1(options) {
+	{
+		return 'fun1';
+	}
+}
+
+function fun2(options) {
+	{
+		return fun1();
+	}
+}
+
+function fun4(options) {
+	{
+		console.log('func4');
+	}
+}
+
+console.log(
+	fun2(),
+	fun4()
+);
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/main.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/main.js
new file mode 100644
index 00000000000..4f845cc4e2c
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal-object/main.js
@@ -0,0 +1,40 @@
+function fun1(options) {
+	if (options.enable) {
+		return 'fun1';
+	} else {
+		console.log('func1');
+	}
+}
+
+function fun2(options) {
+	if (options.enable) {
+		return fun1(options);
+	} else {
+		console.log('func2');
+	}
+}
+
+function fun3(options) {
+	if (options.enable) {
+		return 'fun3';
+	} else {
+		console.log('func3');
+	}
+}
+
+function fun4(options) {
+	if (options.enable) {
+		return fun3(options);
+	} else {
+		console.log('func4');
+	}
+}
+
+console.log(
+	fun2({
+		enable: true
+	}),
+	fun4({
+		enable: false
+	})
+);
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal/_config.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal/_config.js
new file mode 100644
index 00000000000..251df7a6a12
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'function parameters tree-shaken should be recursive if literal'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal/_expected.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal/_expected.js
new file mode 100644
index 00000000000..2fcab0594bc
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal/_expected.js
@@ -0,0 +1,13 @@
+function fun1(enable) {
+	{
+		return 'fun1';
+	}
+}
+
+function fun2(enable) {
+	{
+		return fun1();
+	}
+}
+
+console.log(fun2());
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/recursion-literal/main.js b/test/form/samples/tree-shake-literal-parameter/recursion-literal/main.js
new file mode 100644
index 00000000000..1187cc47fb3
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/recursion-literal/main.js
@@ -0,0 +1,13 @@
+function fun1(enable) {
+	if (enable) {
+		return 'fun1';
+	}
+}
+
+function fun2(enable) {
+	if (enable) {
+		return fun1(enable);
+	}
+}
+
+console.log(fun2(true));
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/reexport-function/_config.js b/test/form/samples/tree-shake-literal-parameter/reexport-function/_config.js
new file mode 100644
index 00000000000..74efd8ee3ad
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/reexport-function/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'function parameters tree-shaken should support reexport'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/reexport-function/_expected.js b/test/form/samples/tree-shake-literal-parameter/reexport-function/_expected.js
new file mode 100644
index 00000000000..fd105290ab6
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/reexport-function/_expected.js
@@ -0,0 +1,7 @@
+function module2 (enable) {
+	{
+		return 'module2'
+	}
+}
+
+console.log(module2());
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/reexport-function/main.js b/test/form/samples/tree-shake-literal-parameter/reexport-function/main.js
new file mode 100644
index 00000000000..c83b279bb08
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/reexport-function/main.js
@@ -0,0 +1,3 @@
+import { module2 } from './module1.js'
+
+console.log(module2(true))
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/reexport-function/module1.js b/test/form/samples/tree-shake-literal-parameter/reexport-function/module1.js
new file mode 100644
index 00000000000..01e152738e8
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/reexport-function/module1.js
@@ -0,0 +1 @@
+export * from './module2.js';
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/reexport-function/module2.js b/test/form/samples/tree-shake-literal-parameter/reexport-function/module2.js
new file mode 100644
index 00000000000..c4f4cacafd1
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/reexport-function/module2.js
@@ -0,0 +1,5 @@
+export function module2 (enable) {
+	if (enable) {
+		return 'module2'
+	}
+}
\ No newline at end of file
diff --git a/test/form/samples/tree-shake-literal-parameter/side-effect/_config.js b/test/form/samples/tree-shake-literal-parameter/side-effect/_config.js
new file mode 100644
index 00000000000..e06ff5cdc74
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/side-effect/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'test tree-shake-literal-parameter with side-effect'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/side-effect/_expected.js b/test/form/samples/tree-shake-literal-parameter/side-effect/_expected.js
new file mode 100644
index 00000000000..77275663462
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/side-effect/_expected.js
@@ -0,0 +1,63 @@
+function foo1() {
+	return 1;
+}
+
+function bar1(foo) {
+	console.log(foo());
+}
+
+function bar2(foo) {
+}
+
+// not pure, preserve
+function foo3() {
+	console.log(1);
+}
+
+function bar3(foo) {
+	foo();
+}
+
+console.log(bar1(foo1), bar2(), bar3(foo3));
+
+const options = {
+	enable: 1
+};
+
+const options2 = {
+	enable: 1
+};
+
+function calledWithSameVariable(options) {
+	{
+		return 'enabled';
+	}
+}
+
+function calledWithDifferentVariable(options) {
+	if (options.enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+}
+
+// forward hasEffects to `options`
+console.log(calledWithSameVariable(), calledWithSameVariable());
+// no optimization
+console.log(calledWithDifferentVariable(options), calledWithDifferentVariable(options2));
+
+const optionsBeModified = {
+	enable: 1
+};
+
+function calledWithModifiedVariable(options) {
+	if (options.enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+}
+
+console.log(calledWithModifiedVariable(optionsBeModified));
+optionsBeModified.enable = 0;
diff --git a/test/form/samples/tree-shake-literal-parameter/side-effect/main.js b/test/form/samples/tree-shake-literal-parameter/side-effect/main.js
new file mode 100644
index 00000000000..d7f3ba00148
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/side-effect/main.js
@@ -0,0 +1,71 @@
+function foo1() {
+	return 1;
+}
+
+function bar1(foo) {
+	console.log(foo())
+}
+
+// pure, can be tree-shaken
+function foo2() {
+	return 1;
+}
+
+function bar2(foo) {
+	foo()
+}
+
+// not pure, preserve
+function foo3() {
+	console.log(1);
+}
+
+function bar3(foo) {
+	foo()
+}
+
+console.log(bar1(foo1), bar2(foo2), bar3(foo3))
+
+const options = {
+	enable: 1
+}
+
+const options2 = {
+	enable: 1
+}
+
+function calledWithSameVariable(options) {
+	if (options.enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+}
+
+function calledWithDifferentVariable(options) {
+	if (options.enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+}
+
+// forward hasEffects to `options`
+console.log(calledWithSameVariable(options), calledWithSameVariable(options))
+// no optimization
+console.log(calledWithDifferentVariable(options), calledWithDifferentVariable(options2))
+
+const optionsBeModified = {
+	enable: 1
+}
+
+function calledWithModifiedVariable(options) {
+	if (options.enable) {
+		return 'enabled';
+	} else {
+		return 'disabled';
+	}
+}
+
+console.log(calledWithModifiedVariable(optionsBeModified))
+optionsBeModified.enable = 0;
diff --git a/test/form/samples/tree-shake-literal-parameter/top-level/_config.js b/test/form/samples/tree-shake-literal-parameter/top-level/_config.js
new file mode 100644
index 00000000000..027f90cf36d
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/top-level/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'Top level exports and global variables should not be optimized'
+});
diff --git a/test/form/samples/tree-shake-literal-parameter/top-level/_expected.js b/test/form/samples/tree-shake-literal-parameter/top-level/_expected.js
new file mode 100644
index 00000000000..70d050ab798
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/top-level/_expected.js
@@ -0,0 +1,23 @@
+function foo(x) {
+	// The exported function might also be called with "false"
+	if (x) console.log('true');
+	else console.log('false');
+}
+
+// global variable should not be optimized
+foo2 = (x) => {
+	if (x) console.log('true');
+	else console.log('false');
+};
+
+// export default should not be optimized
+var main = foo3 = (x) => {
+	if (x) console.log('true');
+	else console.log('false');
+};
+
+foo(true);
+foo2(true);
+foo3(true);
+
+export { main as default, foo };
diff --git a/test/form/samples/tree-shake-literal-parameter/top-level/main.js b/test/form/samples/tree-shake-literal-parameter/top-level/main.js
new file mode 100644
index 00000000000..9f706606d6f
--- /dev/null
+++ b/test/form/samples/tree-shake-literal-parameter/top-level/main.js
@@ -0,0 +1,23 @@
+function foo(x) {
+	// The exported function might also be called with "false"
+	if (x) console.log('true');
+	else console.log('false');
+}
+
+// global variable should not be optimized
+foo2 = (x) => {
+	if (x) console.log('true');
+	else console.log('false');
+}
+
+// export default should not be optimized
+export default foo3 = (x) => {
+	if (x) console.log('true');
+	else console.log('false');
+}
+
+foo(true);
+foo2(true);
+foo3(true);
+
+export { foo };
diff --git a/test/form/samples/try-statement-deoptimization/deactivate-via-option/_expected.js b/test/form/samples/try-statement-deoptimization/deactivate-via-option/_expected.js
index a8d430c8fbb..7a1891aaca5 100644
--- a/test/form/samples/try-statement-deoptimization/deactivate-via-option/_expected.js
+++ b/test/form/samples/try-statement-deoptimization/deactivate-via-option/_expected.js
@@ -6,13 +6,11 @@ const mutated = {};
 
 function test(callback) {
 	try {
-		callback();
 		mutate(mutated);
 	} catch {}
 }
 
-test(() => {
-});
+test();
 
 try {} finally {
 	console.log('retained');
diff --git a/test/function/samples/acorn-walk/_config.js b/test/function/samples/acorn-walk/_config.js
new file mode 100644
index 00000000000..02a5c20f5dd
--- /dev/null
+++ b/test/function/samples/acorn-walk/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'in acorn walk, immediate function lose track so we do not optimize parameter'
+});
diff --git a/test/function/samples/acorn-walk/main.js b/test/function/samples/acorn-walk/main.js
new file mode 100644
index 00000000000..32da4905193
--- /dev/null
+++ b/test/function/samples/acorn-walk/main.js
@@ -0,0 +1,26 @@
+let found = false;
+
+const base = {
+	ExpressionStatement(node, c) {
+		c(node.value, "Expression");
+	},
+	Expression() { },
+	Identifier() { }
+};
+
+function simple(node, visitors, baseVisitor) {
+	if (!baseVisitor) baseVisitor = base
+		; (function c(node, override) {
+			let type = override || node.type
+			baseVisitor[type](node, c)
+			if (visitors[type]) visitors[type](node)
+		})(node)
+}
+
+simple({ type: "ExpressionStatement", value: { type: "Identifier" } }, {
+	Expression(node) {
+		found = true;
+	}
+});
+
+assert.equal(found, true);
diff --git a/test/function/samples/reassigned-parameter-side-effect/_config.js b/test/function/samples/reassigned-parameter-side-effect/_config.js
new file mode 100644
index 00000000000..a1ffc02b258
--- /dev/null
+++ b/test/function/samples/reassigned-parameter-side-effect/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'when a parameter is reassigned, hasEffectsOnInteractionAtPath returns true'
+});
diff --git a/test/function/samples/reassigned-parameter-side-effect/main.js b/test/function/samples/reassigned-parameter-side-effect/main.js
new file mode 100644
index 00000000000..b8d99e0d21b
--- /dev/null
+++ b/test/function/samples/reassigned-parameter-side-effect/main.js
@@ -0,0 +1,14 @@
+function foo(a) {
+	a.x;
+}
+let sideEffect = false
+foo({
+	x: 1
+});
+foo({
+	get x() {
+		sideEffect = true
+	},
+});
+
+assert.equal(sideEffect, true)
diff --git a/test/function/samples/reassigned-parameter/_config.js b/test/function/samples/reassigned-parameter/_config.js
new file mode 100644
index 00000000000..5923f0afe5d
--- /dev/null
+++ b/test/function/samples/reassigned-parameter/_config.js
@@ -0,0 +1,3 @@
+module.exports = defineTest({
+	description: 'parameters reassigned/updated should be detected'
+});
diff --git a/test/function/samples/reassigned-parameter/main.js b/test/function/samples/reassigned-parameter/main.js
new file mode 100644
index 00000000000..f2c6fe7d3f6
--- /dev/null
+++ b/test/function/samples/reassigned-parameter/main.js
@@ -0,0 +1,21 @@
+function f(a) {
+	assert.equal(a ? 'OK' : 'FAIL', 'OK');
+	a = false;
+	assert.equal(a ? 'FAIL' : 'OK', 'OK');
+}
+
+f(true);
+
+function g(array) {
+	if (array === null) {
+		array = [];
+	}
+
+	if (array) {
+		return 'OK';
+	}
+	return array;
+}
+
+assert.equal(g(null), 'OK');
+