Add parser profiler (#1993)

RGHenderson · ydaveluy · web-flow · commit 910e8a01051a · 2025-08-11T19:00:06.000+02:00
Co-authored-by: Yannick Daveluy &lt;yannick.daveluy@gmail.com&gt;
diff --git a/packages/langium/src/default-module.ts b/packages/langium/src/default-module.ts
@@ -117,7 +117,8 @@ export function createDefaultSharedCoreModule(context: DefaultSharedCoreModuleCo
             WorkspaceManager: (services) => new DefaultWorkspaceManager(services),
             FileSystemProvider: (services) => context.fileSystemProvider(services),
             WorkspaceLock: () => new DefaultWorkspaceLock(),
-            ConfigurationProvider: (services) => new DefaultConfigurationProvider(services)
-        }
+            ConfigurationProvider: (services) => new DefaultConfigurationProvider(services),
+        },
+        profilers: {}
     };
 }
diff --git a/packages/langium/src/parser/langium-parser.ts b/packages/langium/src/parser/langium-parser.ts
@@ -5,9 +5,9 @@
  ******************************************************************************/
 
 /* eslint-disable @typescript-eslint/no-explicit-any */
-import type { DSLMethodOpts, ILexingError, IOrAlt, IParserErrorMessageProvider, IRecognitionException, IToken, TokenType, TokenVocabulary, IRuleConfig } from 'chevrotain';
-import type { AbstractElement, Action, Assignment, InfixRule, ParserRule } from '../languages/generated/ast.js';
 import { isInfixRule } from '../languages/generated/ast.js';
+import type { AbstractElement, Action, Assignment, InfixRule, ParserRule } from '../languages/generated/ast.js';
+import type { DSLMethodOpts, ILexingError, IOrAlt, IParserErrorMessageProvider, IRecognitionException, IToken, ParserMethod, SubruleMethodOpts, TokenType, TokenVocabulary, IRuleConfig } from 'chevrotain';
 import type { Linker } from '../references/linker.js';
 import type { LangiumCoreServices } from '../services.js';
 import type { AstNode, AstReflection, CompositeCstNode, CstNode } from '../syntax-tree.js';
@@ -21,6 +21,7 @@ import { getExplicitRuleType, isDataTypeRule } from '../utils/grammar-utils.js';
 import { assignMandatoryProperties, getContainerOfType, linkContentToContainer } from '../utils/ast-utils.js';
 import { CstNodeBuilder } from './cst-node-builder.js';
 import type { LexingReport } from './token-builder.js';
+import type { ProfilingTask } from '../workspace/profiler.js';
 
 export type ParseResult<T = AstNode> = {
     value: T,
@@ -140,11 +141,19 @@ export abstract class AbstractLangiumParser implements BaseParser {
         this.lexer = services.parser.Lexer;
         const tokens = this.lexer.definition;
         const production = services.LanguageMetaData.mode === 'production';
-        this.wrapper = new ChevrotainWrapper(tokens, {
-            ...services.parser.ParserConfig,
-            skipValidations: production,
-            errorMessageProvider: services.parser.ParserErrorMessageProvider
-        });
+        if (services.shared.profilers.LangiumProfiler?.isActive('parsing')) {
+            this.wrapper = new ProfilerWrapper(tokens, {
+                ...services.parser.ParserConfig,
+                skipValidations: production,
+                errorMessageProvider: services.parser.ParserErrorMessageProvider
+            }, services.shared.profilers.LangiumProfiler.createTask('parsing', services.LanguageMetaData.languageId));
+        } else {
+            this.wrapper = new ChevrotainWrapper(tokens, {
+                ...services.parser.ParserConfig,
+                skipValidations: production,
+                errorMessageProvider: services.parser.ParserErrorMessageProvider
+            });
+        }
     }
 
     alternatives(idx: number, choices: Array<IOrAlt<any>>): void {
@@ -283,7 +292,7 @@ export class LangiumParser extends AbstractLangiumParser {
     }
 
     private doParse(rule: RuleResult): any {
-        let result = rule.call(this.wrapper, {});
+        let result = this.wrapper.rule(rule);
         if (this.stack.length > 0) {
             // In case the parser throws on the entry rule, `construct` is not called
             // We need to call it manually here
@@ -846,4 +855,40 @@ class ChevrotainWrapper extends EmbeddedActionsParser {
     wrapAtLeastOne(idx: number, callback: DSLMethodOpts<unknown>): void {
         this.atLeastOne(idx, callback);
     }
+    rule(rule: RuleResult): any {
+        return rule.call(this, {});
+    }
+}
+
+class ProfilerWrapper extends ChevrotainWrapper {
+    private readonly task: ProfilingTask;
+    constructor(tokens: TokenVocabulary, config: IParserConfig, task: ProfilingTask) {
+        super(tokens, config);
+        this.task = task;
+    }
+
+    override rule(rule: RuleResult): any {
+        this.task.start();
+        this.task.startSubTask(this.ruleName(rule));
+        try {
+            return super.rule(rule);
+        }
+        finally {
+            this.task.stopSubTask(this.ruleName(rule));
+            this.task.stop();
+        }
+    }
+
+    private ruleName(rule: any): string {
+        return rule.ruleName as string;
+    }
+    protected override subrule<ARGS extends unknown[], R>(idx: number, ruleToCall: ParserMethod<ARGS, R>, options?: SubruleMethodOpts<ARGS>): R {
+        this.task.startSubTask(this.ruleName(ruleToCall));
+        try {
+            return super.subrule<ARGS, R>(idx, ruleToCall, options);
+        }
+        finally {
+            this.task.stopSubTask(this.ruleName(ruleToCall));
+        }
+    }
 }
diff --git a/packages/langium/src/references/linker.ts b/packages/langium/src/references/linker.ts
@@ -14,6 +14,7 @@ import { isAstNode, isAstNodeDescription, isLinkingError } from '../syntax-tree.
 import { findRootNode, streamAst, streamReferences } from '../utils/ast-utils.js';
 import { interruptAndCheck } from '../utils/promise-utils.js';
 import { DocumentState } from '../workspace/documents.js';
+import type { LangiumProfiler } from '../workspace/profiler.js';
 
 /**
  * Language-specific service for resolving cross-references in the AST.
@@ -95,18 +96,44 @@ export class DefaultLinker implements Linker {
     protected readonly scopeProvider: ScopeProvider;
     protected readonly astNodeLocator: AstNodeLocator;
     protected readonly langiumDocuments: () => LangiumDocuments;
+    protected readonly profiler: LangiumProfiler | undefined;
+    protected readonly languageId: string;
 
     constructor(services: LangiumCoreServices) {
         this.reflection = services.shared.AstReflection;
         this.langiumDocuments = () => services.shared.workspace.LangiumDocuments;
         this.scopeProvider = services.references.ScopeProvider;
         this.astNodeLocator = services.workspace.AstNodeLocator;
+        this.profiler = services.shared.profilers.LangiumProfiler;
+        this.languageId = services.LanguageMetaData.languageId;
     }
 
     async link(document: LangiumDocument, cancelToken = CancellationToken.None): Promise<void> {
-        for (const node of streamAst(document.parseResult.value)) {
-            await interruptAndCheck(cancelToken);
-            streamReferences(node).forEach(ref => this.doLink(ref, document));
+        if (this.profiler?.isActive('linking')) {
+            const task = this.profiler.createTask('linking', this.languageId);
+            task.start();
+            try {
+                for (const node of streamAst(document.parseResult.value)) {
+                    await interruptAndCheck(cancelToken);
+                    streamReferences(node).forEach(ref => {
+                        const name = `${node.$type}:${ref.property}`;
+                        task.startSubTask(name);
+                        try {
+                            this.doLink(ref, document);
+                        } finally {
+                            task.stopSubTask(name);
+                        }
+                    });
+                }
+            } finally {
+                task.stop();
+            }
+        }
+        else {
+            for (const node of streamAst(document.parseResult.value)) {
+                await interruptAndCheck(cancelToken);
+                streamReferences(node).forEach(ref => this.doLink(ref, document));
+            }
         }
     }
 
diff --git a/packages/langium/src/services.ts b/packages/langium/src/services.ts
@@ -37,6 +37,7 @@ import type { IndexManager } from './workspace/index-manager.js';
 import type { WorkspaceLock } from './workspace/workspace-lock.js';
 import type { Hydrator } from './serializer/hydrator.js';
 import type { WorkspaceManager } from './workspace/workspace-manager.js';
+import type { LangiumProfiler } from './workspace/profiler.js';
 
 /**
  * The services generated by `langium-cli` for a specific language. These are derived from the
@@ -122,6 +123,9 @@ export type LangiumDefaultSharedCoreServices = {
         readonly WorkspaceLock: WorkspaceLock
         readonly WorkspaceManager: WorkspaceManager
     }
+    readonly profilers: {
+        readonly LangiumProfiler?: LangiumProfiler
+    }
 }
 
 /**
diff --git a/packages/langium/src/validation/document-validator.ts b/packages/langium/src/validation/document-validator.ts
@@ -19,6 +19,7 @@ import { tokenToRange } from '../utils/cst-utils.js';
 import { interruptAndCheck, isOperationCancelled } from '../utils/promise-utils.js';
 import { diagnosticData } from './validation-registry.js';
 import type { LexingDiagnostic, LexingDiagnosticSeverity } from '../parser/token-builder.js';
+import type { LangiumProfiler } from '../workspace/profiler.js';
 
 export interface ValidationOptions {
     /**
@@ -53,10 +54,14 @@ export class DefaultDocumentValidator implements DocumentValidator {
 
     protected readonly validationRegistry: ValidationRegistry;
     protected readonly metadata: LanguageMetaData;
+    protected readonly profiler: LangiumProfiler | undefined;
+    protected readonly languageId: string;
 
     constructor(services: LangiumCoreServices) {
         this.validationRegistry = services.validation.ValidationRegistry;
         this.metadata = services.LanguageMetaData;
+        this.profiler = services.shared.profilers.LangiumProfiler;
+        this.languageId = services.LanguageMetaData.languageId;
     }
 
     async validateDocument(document: LangiumDocument, options: ValidationOptions = {}, cancelToken = CancellationToken.None): Promise<Diagnostic[]> {
@@ -201,13 +206,34 @@ export class DefaultDocumentValidator implements DocumentValidator {
     }
 
     protected async validateAstNodes(rootNode: AstNode, options: ValidationOptions, acceptor: ValidationAcceptor, cancelToken = CancellationToken.None): Promise<void> {
-        await Promise.all(streamAst(rootNode).map(async node => {
-            await interruptAndCheck(cancelToken);
-            const checks = this.validationRegistry.getChecks(node.$type, options.categories);
-            for (const check of checks) {
-                await check(node, acceptor, cancelToken);
+        if (this.profiler?.isActive('validating')) {
+            const task = this.profiler.createTask('validating', this.languageId);
+            task.start();
+            try {
+                streamAst(rootNode).forEach(node => {
+                    task.startSubTask(node.$type);
+                    try {
+                        const checks = this.validationRegistry.getChecks(node.$type, options.categories);
+                        for (const check of checks) {
+                            check(node, acceptor, cancelToken);
+                        }
+                    } finally {
+                        task.stopSubTask(node.$type);
+                    }
+                });
+            } finally {
+                task.stop();
             }
-        }));
+        }
+        else {
+            await Promise.all(streamAst(rootNode).map(async node => {
+                await interruptAndCheck(cancelToken);
+                const checks = this.validationRegistry.getChecks(node.$type, options.categories);
+                for (const check of checks) {
+                    await check(node, acceptor, cancelToken);
+                }
+            }));
+        }
     }
 
     protected async validateAstAfter(rootNode: AstNode, options: ValidationOptions, acceptor: ValidationAcceptor, cancelToken = CancellationToken.None): Promise<void> {
diff --git a/packages/langium/src/workspace/index.ts b/packages/langium/src/workspace/index.ts
@@ -13,3 +13,4 @@ export * from './file-system-provider.js';
 export * from './index-manager.js';
 export * from './workspace-lock.js';
 export * from './workspace-manager.js';
+export * from './profiler.js';
diff --git a/packages/langium/src/workspace/profiler.ts b/packages/langium/src/workspace/profiler.ts
