perf(compiler): make the creation of ts.Program faster. (#19275)

We now create 2 programs with exactly the same fileNames and
exactly the same `import` / `export` declarations,
allowing TS to reuse the structure of first program
completely. When passing in an oldProgram and the files didn’t change,
TS can also reuse the old program completely.

This is possible buy adding generated files to TS
in `host.geSourceFile` via `ts.SourceFile.referencedFiles`.

This commit also:
- has a minor side effect on how we generate shared stylesheets:
  - previously every import in a stylesheet would generate a new
    `.ngstyles.ts` file.
  - now, we only generate 1 `.ngstyles.ts` file per entry in `@Component.styleUrls`.
  This was required as we need to be able to determine the program files
  without loading the resources (which can be async).
- makes all angular related methods in `CompilerHost`
  optional, allowing to just use a regular `ts.CompilerHost` as `CompilerHost`.
- simplifies the logic around `Compiler.analyzeNgModules` by introducing `NgAnalyzedFile`.

Perf impact: 1.5s improvement in compiling angular io
PR Close #19275

packages/compiler/src/jit/compiler.ts

@@ -6,18 +6,18 @@
  * found in the LICENSE file at https://angular.io/license
  */
 
-import {CompileDirectiveMetadata, CompileIdentifierMetadata, CompileNgModuleMetadata, CompileProviderMetadata, CompileStylesheetMetadata, CompileTypeSummary, ProviderMeta, ProxyClass, createHostComponentMeta, identifierName, ngModuleJitUrl, sharedStylesheetJitUrl, templateJitUrl, templateSourceUrl} from '../compile_metadata';
+import {CompileDirectiveMetadata, CompileIdentifierMetadata, CompileNgModuleMetadata, CompilePipeSummary, CompileProviderMetadata, CompileStylesheetMetadata, CompileTypeSummary, ProviderMeta, ProxyClass, identifierName, ngModuleJitUrl, sharedStylesheetJitUrl, templateJitUrl, templateSourceUrl} from '../compile_metadata';
 import {CompileReflector} from '../compile_reflector';
 import {CompilerConfig} from '../config';
 import {Type} from '../core';
 import {CompileMetadataResolver} from '../metadata_resolver';
-import {HtmlParser} from '../ml_parser/html_parser';
 import {NgModuleCompiler} from '../ng_module_compiler';
 import * as ir from '../output/output_ast';
 import {interpretStatements} from '../output/output_interpreter';
 import {jitStatements} from '../output/output_jit';
 import {CompiledStylesheet, StyleCompiler} from '../style_compiler';
 import {SummaryResolver} from '../summary_resolver';
+import {TemplateAst} from '../template_parser/template_ast';
 import {TemplateParser} from '../template_parser/template_parser';
 import {Console, OutputContext, SyncAsync, stringify} from '../util';
 import {ViewCompiler} from '../view_compiler/view_compiler';
@@ -44,11 +44,11 @@ export class JitCompiler {
   private _sharedStylesheetCount = 0;
 
   constructor(
-      private _metadataResolver: CompileMetadataResolver, private _htmlParser: HtmlParser,
-      private _templateParser: TemplateParser, private _styleCompiler: StyleCompiler,
-      private _viewCompiler: ViewCompiler, private _ngModuleCompiler: NgModuleCompiler,
-      private _summaryResolver: SummaryResolver<Type>, private _reflector: CompileReflector,
-      private _compilerConfig: CompilerConfig, private _console: Console,
+      private _metadataResolver: CompileMetadataResolver, private _templateParser: TemplateParser,
+      private _styleCompiler: StyleCompiler, private _viewCompiler: ViewCompiler,
+      private _ngModuleCompiler: NgModuleCompiler, private _summaryResolver: SummaryResolver<Type>,
+      private _reflector: CompileReflector, private _compilerConfig: CompilerConfig,
+      private _console: Console,
       private getExtraNgModuleProviders: (ngModule: any) => CompileProviderMetadata[]) {}
 
   compileModuleSync(moduleType: Type): object {
@@ -227,9 +227,8 @@ export class JitCompiler {
       const compMeta = this._metadataResolver.getDirectiveMetadata(compType);
       assertComponent(compMeta);
 
-      const hostClass = this._metadataResolver.getHostComponentType(compType);
-      const hostMeta = createHostComponentMeta(
-          hostClass, compMeta, (compMeta.componentFactory as any).viewDefFactory, this._htmlParser);
+      const hostMeta = this._metadataResolver.getHostComponentMetadata(
+          compMeta, (compMeta.componentFactory as any).viewDefFactory);
       compiledTemplate =
           new CompiledTemplate(true, compMeta.type, hostMeta, ngModule, [compMeta.type]);
       this._compiledHostTemplateCache.set(compType, compiledTemplate);
@@ -257,21 +256,16 @@ export class JitCompiler {
     const externalStylesheetsByModuleUrl = new Map<string, CompiledStylesheet>();
     const outputContext = createOutputContext();
     const componentStylesheet = this._styleCompiler.compileComponent(outputContext, compMeta);
-    const preserveWhitespaces = compMeta !.template !.preserveWhitespaces;
     compMeta.template !.externalStylesheets.forEach((stylesheetMeta) => {
       const compiledStylesheet =
           this._styleCompiler.compileStyles(createOutputContext(), compMeta, stylesheetMeta);
       externalStylesheetsByModuleUrl.set(stylesheetMeta.moduleUrl !, compiledStylesheet);
     });
     this._resolveStylesCompileResult(componentStylesheet, externalStylesheetsByModuleUrl);
-    const directives =
-        template.directives.map(dir => this._metadataResolver.getDirectiveSummary(dir.reference));
     const pipes = template.ngModule.transitiveModule.pipes.map(
         pipe => this._metadataResolver.getPipeSummary(pipe.reference));
-    const {template: parsedTemplate, pipes: usedPipes} = this._templateParser.parse(
-        compMeta, compMeta.template !.template !, directives, pipes, template.ngModule.schemas,
-        templateSourceUrl(template.ngModule.type, template.compMeta, template.compMeta.template !),
-        preserveWhitespaces);
+    const {template: parsedTemplate, pipes: usedPipes} =
+        this._parseTemplate(compMeta, template.ngModule, template.directives);
     const compileResult = this._viewCompiler.compileComponent(
         outputContext, compMeta, parsedTemplate, ir.variable(componentStylesheet.stylesVar),
         usedPipes);
@@ -282,6 +276,21 @@ export class JitCompiler {
     template.compiled(viewClass, rendererType);
   }
 
+  private _parseTemplate(
+      compMeta: CompileDirectiveMetadata, ngModule: CompileNgModuleMetadata,
+      directiveIdentifiers: CompileIdentifierMetadata[]):
+      {template: TemplateAst[], pipes: CompilePipeSummary[]} {
+    // Note: ! is ok here as components always have a template.
+    const preserveWhitespaces = compMeta.template !.preserveWhitespaces;
+    const directives =
+        directiveIdentifiers.map(dir => this._metadataResolver.getDirectiveSummary(dir.reference));
+    const pipes = ngModule.transitiveModule.pipes.map(
+        pipe => this._metadataResolver.getPipeSummary(pipe.reference));
+    return this._templateParser.parse(
+        compMeta, compMeta.template !.htmlAst !, directives, pipes, ngModule.schemas,
+        templateSourceUrl(ngModule.type, compMeta, compMeta.template !), preserveWhitespaces);
+  }
+
   private _resolveStylesCompileResult(
       result: CompiledStylesheet, externalStylesheetsByModuleUrl: Map<string, CompiledStylesheet>) {
     result.dependencies.forEach((dep, i) => {