GoScrobble/web/node_modules/@webassemblyjs/helper-wasm-section/lib/resize.js

90 lines
3.1 KiB
JavaScript
Raw Permalink Normal View History

2022-04-25 02:47:15 +00:00
"use strict";
Object.defineProperty(exports, "__esModule", {
value: true
});
exports.resizeSectionByteSize = resizeSectionByteSize;
exports.resizeSectionVecSize = resizeSectionVecSize;
var _wasmGen = require("@webassemblyjs/wasm-gen");
var _ast = require("@webassemblyjs/ast");
var _helperBuffer = require("@webassemblyjs/helper-buffer");
function resizeSectionByteSize(ast, uint8Buffer, section, deltaBytes) {
var sectionMetadata = (0, _ast.getSectionMetadata)(ast, section);
if (typeof sectionMetadata === "undefined") {
throw new Error("Section metadata not found");
}
if (typeof sectionMetadata.size.loc === "undefined") {
throw new Error("SectionMetadata " + section + " has no loc");
} // keep old node location to be overriden
var start = sectionMetadata.size.loc.start.column;
var end = sectionMetadata.size.loc.end.column;
var newSectionSize = sectionMetadata.size.value + deltaBytes;
var newBytes = (0, _wasmGen.encodeU32)(newSectionSize);
/**
* update AST
*/
sectionMetadata.size.value = newSectionSize;
var oldu32EncodedLen = end - start;
var newu32EncodedLen = newBytes.length; // the new u32 has a different encoded length
if (newu32EncodedLen !== oldu32EncodedLen) {
var deltaInSizeEncoding = newu32EncodedLen - oldu32EncodedLen;
sectionMetadata.size.loc.end.column = start + newu32EncodedLen;
deltaBytes += deltaInSizeEncoding; // move the vec size pointer size the section size is now smaller
sectionMetadata.vectorOfSize.loc.start.column += deltaInSizeEncoding;
sectionMetadata.vectorOfSize.loc.end.column += deltaInSizeEncoding;
} // Once we hit our section every that is after needs to be shifted by the delta
var encounteredSection = false;
(0, _ast.traverse)(ast, {
SectionMetadata: function SectionMetadata(path) {
if (path.node.section === section) {
encounteredSection = true;
return;
}
if (encounteredSection === true) {
(0, _ast.shiftSection)(ast, path.node, deltaBytes);
}
}
});
return (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, start, end, newBytes);
}
function resizeSectionVecSize(ast, uint8Buffer, section, deltaElements) {
var sectionMetadata = (0, _ast.getSectionMetadata)(ast, section);
if (typeof sectionMetadata === "undefined") {
throw new Error("Section metadata not found");
}
if (typeof sectionMetadata.vectorOfSize.loc === "undefined") {
throw new Error("SectionMetadata " + section + " has no loc");
} // Section has no vector
if (sectionMetadata.vectorOfSize.value === -1) {
return uint8Buffer;
} // keep old node location to be overriden
var start = sectionMetadata.vectorOfSize.loc.start.column;
var end = sectionMetadata.vectorOfSize.loc.end.column;
var newValue = sectionMetadata.vectorOfSize.value + deltaElements;
var newBytes = (0, _wasmGen.encodeU32)(newValue); // Update AST
sectionMetadata.vectorOfSize.value = newValue;
sectionMetadata.vectorOfSize.loc.end.column = start + newBytes.length;
return (0, _helperBuffer.overrideBytesInBuffer)(uint8Buffer, start, end, newBytes);
}