Merge pull request #21002 from calixteman/ps_eval

[api-minor] Rewrite the ps lexer & parser and add a small Wasm compiler

Author: calixteman

src/core/function.js

@@ -21,18 +21,30 @@ import {
   MathClamp,
   shadow,
   unreachable,
+  warn,
 } from "../shared/util.js";
 import { PostScriptLexer, PostScriptParser } from "./ps_parser.js";
 import { BaseStream } from "./base_stream.js";
+import { buildPostScriptWasmFunction } from "./postscript/wasm_compiler.js";
 import { isNumberArray } from "./core_utils.js";
 import { LocalFunctionCache } from "./image_utils.js";
 
 class PDFFunctionFactory {
+  static #useWasm = true;
+
+  static setOptions({ useWasm }) {
+    PDFFunctionFactory.#useWasm = useWasm;
+  }
+
   constructor({ xref, isEvalSupported = true }) {
     this.xref = xref;
     this.isEvalSupported = isEvalSupported !== false;
   }
 
+  get useWasm() {
+    return PDFFunctionFactory.#useWasm;
+  }
+
   create(fn, parseArray = false) {
     let fnRef, parsedFn;
 
@@ -358,6 +370,24 @@ class PDFFunction {
       throw new FormatError("No range.");
     }
 
+    if (factory.useWasm) {
+      try {
+        const wasmFn = buildPostScriptWasmFunction(
+          fn.getString(),
+          domain,
+          range
+        );
+        if (wasmFn) {
+          return wasmFn; // (src, srcOffset, dest, destOffset) → void
+        }
+      } catch {
+        // Fall through to the existing interpreter-based path.
+      }
+    }
+
+    warn("Unable to compile PS function, using interpreter");
+    fn.reset();
+
     const lexer = new PostScriptLexer(fn);
     const parser = new PostScriptParser(lexer);
     const code = parser.parse();

src/core/pdf_manager.js

@@ -28,6 +28,7 @@ import { JpxImage } from "./jpx.js";
 import { MissingDataException } from "./core_utils.js";
 import { OperatorList } from "./operator_list.js";
 import { PDFDocument } from "./document.js";
+import { PDFFunctionFactory } from "./function.js";
 import { Stream } from "./stream.js";
 
 function parseDocBaseUrl(url) {
@@ -97,6 +98,7 @@ class BasePdfManager {
     IccColorSpace.setOptions(options);
     CmykICCBasedCS.setOptions(options);
     JBig2CCITTFaxWasmImage.setOptions(options);
+    PDFFunctionFactory.setOptions(options);
   }
 
   get docId() {