source: trip-planner-front/node_modules/@webassemblyjs/helper-wasm-section/esm/create.js@ 6c1585f

Last change on this file since 6c1585f was 6a3a178, checked in by Ema <ema_spirova@…>, 3 years ago

initial commit

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1function _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); }
2
3import { encodeNode } from "@webassemblyjs/wasm-gen";
4import { overrideBytesInBuffer } from "@webassemblyjs/helper-buffer";
5import constants from "@webassemblyjs/helper-wasm-bytecode";
6import * as t from "@webassemblyjs/ast";
7
8function findLastSection(ast, forSection) {
9 var targetSectionId = constants.sections[forSection]; // $FlowIgnore: metadata can not be empty
10
11 var moduleSections = ast.body[0].metadata.sections;
12 var lastSection;
13 var lastId = 0;
14
15 for (var i = 0, len = moduleSections.length; i < len; i++) {
16 var section = moduleSections[i]; // Ignore custom section since they can actually occur everywhere
17
18 if (section.section === "custom") {
19 continue;
20 }
21
22 var sectionId = constants.sections[section.section];
23
24 if (targetSectionId > lastId && targetSectionId < sectionId) {
25 return lastSection;
26 }
27
28 lastId = sectionId;
29 lastSection = section;
30 }
31
32 return lastSection;
33}
34
35export function createEmptySection(ast, uint8Buffer, section) {
36 // previous section after which we are going to insert our section
37 var lastSection = findLastSection(ast, section);
38 var start, end;
39 /**
40 * It's the first section
41 */
42
43 if (lastSection == null || lastSection.section === "custom") {
44 start = 8
45 /* wasm header size */
46 ;
47 end = start;
48 } else {
49 start = lastSection.startOffset + lastSection.size.value + 1;
50 end = start;
51 } // section id
52
53
54 start += 1;
55 var sizeStartLoc = {
56 line: -1,
57 column: start
58 };
59 var sizeEndLoc = {
60 line: -1,
61 column: start + 1
62 }; // 1 byte for the empty vector
63
64 var size = t.withLoc(t.numberLiteralFromRaw(1), sizeEndLoc, sizeStartLoc);
65 var vectorOfSizeStartLoc = {
66 line: -1,
67 column: sizeEndLoc.column
68 };
69 var vectorOfSizeEndLoc = {
70 line: -1,
71 column: sizeEndLoc.column + 1
72 };
73 var vectorOfSize = t.withLoc(t.numberLiteralFromRaw(0), vectorOfSizeEndLoc, vectorOfSizeStartLoc);
74 var sectionMetadata = t.sectionMetadata(section, start, size, vectorOfSize);
75 var sectionBytes = encodeNode(sectionMetadata);
76 uint8Buffer = overrideBytesInBuffer(uint8Buffer, start - 1, end, sectionBytes); // Add section into the AST for later lookups
77
78 if (_typeof(ast.body[0].metadata) === "object") {
79 // $FlowIgnore: metadata can not be empty
80 ast.body[0].metadata.sections.push(sectionMetadata);
81 t.sortSectionMetadata(ast.body[0]);
82 }
83 /**
84 * Update AST
85 */
86 // Once we hit our section every that is after needs to be shifted by the delta
87
88
89 var deltaBytes = +sectionBytes.length;
90 var encounteredSection = false;
91 t.traverse(ast, {
92 SectionMetadata: function SectionMetadata(path) {
93 if (path.node.section === section) {
94 encounteredSection = true;
95 return;
96 }
97
98 if (encounteredSection === true) {
99 t.shiftSection(ast, path.node, deltaBytes);
100 }
101 }
102 });
103 return {
104 uint8Buffer: uint8Buffer,
105 sectionMetadata: sectionMetadata
106 };
107}
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