record-allocations.js

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// Tests for JS::EnableRecordingAllocations testing functions.

load(libdir + "asserts.js");

function countClass(entries, className) {

  return entries.filter(e => e.className === className).length;

startRecordingAllocations();

var keep = [];

for (var i = 0; i < 10; i++) {

  keep.push({});

  keep.push([]);

  keep.push(new Map());

  keep.push(new Uint8Array(4));

var entries = stopRecordingAllocations();

assertEq(Array.isArray(entries), true);

assertEq(countClass(entries, "Object") >= 10, true);

assertEq(countClass(entries, "Array") >= 10, true);

assertEq(countClass(entries, "Map") >= 10, true);

assertEq(countClass(entries, "Uint8Array") >= 10, true);

for (var e of entries) {

  assertEq(typeof e.typeName, "string");

  assertEq(typeof e.className, "string");

  assertEq(e.coarseType, "Object");

  assertEq(typeof e.size, "number");

  assertEq(e.size > 0, true);

  assertEq(typeof e.inNursery, "boolean");

// Nothing is recorded after stopping.

assertThrowsInstanceOf(() => stopRecordingAllocations(), Error);

// Probability 0 records nothing.

startRecordingAllocations(0);

for (var i = 0; i < 10; i++) {

  keep.push({});

  keep.push(new Map());

assertEq(stopRecordingAllocations().length, 0);

// Invalid probabilities.

assertThrowsInstanceOf(() => startRecordingAllocations(-1), Error);

assertThrowsInstanceOf(() => startRecordingAllocations(2), Error);

assertThrowsInstanceOf(() => startRecordingAllocations(NaN), Error);

// Starting twice keeps a single log.

startRecordingAllocations();

keep.push(new Set());

startRecordingAllocations();

keep.push(new Set());

assertEq(countClass(stopRecordingAllocations(), "Set") >= 2, true);