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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
"use strict";
const wasmStates = new WeakMap();
function getWasmText(subject, data) {
const parser = new wasmparser.BinaryReader();
parser.setData(data.buffer, 0, data.length);
const dis = new wasmdis.WasmDisassembler();
dis.addOffsets = true;
const done = dis.disassembleChunk(parser);
let result = dis.getResult();
if (result.lines.length === 0) {
result = { lines: ["No luck with wast conversion"], offsets: [0], done };
}
const offsets = result.offsets,
lines = [];
for (let i = 0; i < offsets.length; i++) {
lines[offsets[i]] = i;
}
wasmStates.set(subject, { offsets, lines });
return { lines: result.lines, done: result.done };
}
function getWasmLineNumberFormatter(subject) {
const codeOf0 = 48,
codeOfA = 65;
const buffer = [
codeOf0,
codeOf0,
codeOf0,
codeOf0,
codeOf0,
codeOf0,
codeOf0,
codeOf0,
];
let last0 = 7;
return function (number) {
const offset = lineToWasmOffset(subject, number - 1);
if (offset === undefined) {
return "";
}
let i = 7;
for (let n = offset | 0; n !== 0 && i >= 0; n >>= 4, i--) {
const nibble = n & 15;
buffer[i] = nibble < 10 ? codeOf0 + nibble : codeOfA - 10 + nibble;
}
for (let j = i; j > last0; j--) {
buffer[j] = codeOf0;
}
last0 = i;
return String.fromCharCode.apply(null, buffer);
};
}
function isWasm(subject) {
return wasmStates.has(subject);
}
function lineToWasmOffset(subject, number) {
const wasmState = wasmStates.get(subject);
if (!wasmState) {
return undefined;
}
let offset = wasmState.offsets[number];
while (offset === undefined && number > 0) {
offset = wasmState.offsets[--number];
}
return offset;
}
function wasmOffsetToLine(subject, offset) {
const wasmState = wasmStates.get(subject);
return wasmState.lines[offset];
}
module.exports = {
getWasmText,
getWasmLineNumberFormatter,
isWasm,
lineToWasmOffset,
wasmOffsetToLine,
};