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- function _typeof(obj) { if (typeof Symbol === "function" && typeof Symbol.iterator === "symbol") { _typeof = function _typeof(obj) { return typeof obj; }; } else { _typeof = function _typeof(obj) { return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj; }; } return _typeof(obj); }
-
- import { encodeNode } from "@webassemblyjs/wasm-gen";
- import { overrideBytesInBuffer } from "@webassemblyjs/helper-buffer";
- import constants from "@webassemblyjs/helper-wasm-bytecode";
- import * as t from "@webassemblyjs/ast";
-
- function findLastSection(ast, forSection) {
- var targetSectionId = constants.sections[forSection]; // $FlowIgnore: metadata can not be empty
-
- var moduleSections = ast.body[0].metadata.sections;
- var lastSection;
- var lastId = 0;
-
- for (var i = 0, len = moduleSections.length; i < len; i++) {
- var section = moduleSections[i]; // Ignore custom section since they can actually occur everywhere
-
- if (section.section === "custom") {
- continue;
- }
-
- var sectionId = constants.sections[section.section];
-
- if (targetSectionId > lastId && targetSectionId < sectionId) {
- return lastSection;
- }
-
- lastId = sectionId;
- lastSection = section;
- }
-
- return lastSection;
- }
-
- export function createEmptySection(ast, uint8Buffer, section) {
- // previous section after which we are going to insert our section
- var lastSection = findLastSection(ast, section);
- var start, end;
- /**
- * It's the first section
- */
-
- if (lastSection == null || lastSection.section === "custom") {
- start = 8
- /* wasm header size */
- ;
- end = start;
- } else {
- start = lastSection.startOffset + lastSection.size.value + 1;
- end = start;
- } // section id
-
-
- start += 1;
- var sizeStartLoc = {
- line: -1,
- column: start
- };
- var sizeEndLoc = {
- line: -1,
- column: start + 1
- }; // 1 byte for the empty vector
-
- var size = t.withLoc(t.numberLiteralFromRaw(1), sizeEndLoc, sizeStartLoc);
- var vectorOfSizeStartLoc = {
- line: -1,
- column: sizeEndLoc.column
- };
- var vectorOfSizeEndLoc = {
- line: -1,
- column: sizeEndLoc.column + 1
- };
- var vectorOfSize = t.withLoc(t.numberLiteralFromRaw(0), vectorOfSizeEndLoc, vectorOfSizeStartLoc);
- var sectionMetadata = t.sectionMetadata(section, start, size, vectorOfSize);
- var sectionBytes = encodeNode(sectionMetadata);
- uint8Buffer = overrideBytesInBuffer(uint8Buffer, start - 1, end, sectionBytes); // Add section into the AST for later lookups
-
- if (_typeof(ast.body[0].metadata) === "object") {
- // $FlowIgnore: metadata can not be empty
- ast.body[0].metadata.sections.push(sectionMetadata);
- t.sortSectionMetadata(ast.body[0]);
- }
- /**
- * Update AST
- */
- // Once we hit our section every that is after needs to be shifted by the delta
-
-
- var deltaBytes = +sectionBytes.length;
- var encounteredSection = false;
- t.traverse(ast, {
- SectionMetadata: function SectionMetadata(path) {
- if (path.node.section === section) {
- encounteredSection = true;
- return;
- }
-
- if (encounteredSection === true) {
- t.shiftSection(ast, path.node, deltaBytes);
- }
- }
- });
- return {
- uint8Buffer: uint8Buffer,
- sectionMetadata: sectionMetadata
- };
- }
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