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Inline all the possible type checks in PartialEvaluator.hasBlendModes to avoid unnecessary function calls

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For badly generated PDF documents, with issue 6961 being one example, there's well over one hundred thousand function calls being made in total for just the *two* pages.
This commit is contained in:
Jonas Jenwald 2019-10-12 11:24:37 +02:00
parent dcf49ac753
commit af71f9b40a
1 changed files with 12 additions and 14 deletions
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26
src/core/evaluator.js
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@ -21,7 +21,7 @@ import {
} from '../shared/util';
import { CMapFactory, IdentityCMap } from './cmap';
import {
Cmd, Dict, EOF, isDict, isName, isRef, isStream, Name
Cmd, Dict, EOF, isDict, isName, isRef, isStream, Name, Ref
} from './primitives';
import {
ErrorFont, Font, FontFlags, getFontType, IdentityToUnicodeMap, ToUnicodeMap
@ -180,7 +180,7 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
},
hasBlendModes: function PartialEvaluator_hasBlendModes(resources) {
if (!isDict(resources)) {
if (!(resources instanceof Dict)) {
return false;
}
@ -191,33 +191,32 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
var nodes = [resources], xref = this.xref;
while (nodes.length) {
var key, i, ii;
var node = nodes.shift();
// First check the current resources for blend modes.
var graphicStates = node.get('ExtGState');
if (isDict(graphicStates)) {
if (graphicStates instanceof Dict) {
var graphicStatesKeys = graphicStates.getKeys();
for (i = 0, ii = graphicStatesKeys.length; i < ii; i++) {
key = graphicStatesKeys[i];
for (let i = 0, ii = graphicStatesKeys.length; i < ii; i++) {
const key = graphicStatesKeys[i];
var graphicState = graphicStates.get(key);
var bm = graphicState.get('BM');
if (isName(bm) && bm.name !== 'Normal') {
if ((bm instanceof Name) && bm.name !== 'Normal') {
return true;
}
}
}
// Descend into the XObjects to look for more resources and blend modes.
var xObjects = node.get('XObject');
if (!isDict(xObjects)) {
if (!(xObjects instanceof Dict)) {
continue;
}
var xObjectsKeys = xObjects.getKeys();
for (i = 0, ii = xObjectsKeys.length; i < ii; i++) {
key = xObjectsKeys[i];
for (let i = 0, ii = xObjectsKeys.length; i < ii; i++) {
const key = xObjectsKeys[i];
var xObject = xObjects.getRaw(key);
if (isRef(xObject)) {
if (xObject instanceof Ref) {
if (processed[xObject.toString()]) {
// The XObject has already been processed, and by avoiding a
// redundant `xref.fetch` we can *significantly* reduce the load
@ -231,14 +230,13 @@ var PartialEvaluator = (function PartialEvaluatorClosure() {
}
if (xObject.dict.objId) {
if (processed[xObject.dict.objId]) {
// stream has objId and is processed already
continue;
continue; // Stream has objId and was processed already.
}
processed[xObject.dict.objId] = true;
}
var xResources = xObject.dict.get('Resources');
// Checking objId to detect an infinite loop.
if (isDict(xResources) &&
if ((xResources instanceof Dict) &&
(!xResources.objId || !processed[xResources.objId])) {
nodes.push(xResources);
if (xResources.objId) {