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// Test NaN canonicalisation when reading from a DataView.
load(libdir + "dataview.js");
// Float16
function testF16() {
function writeBE(ui16, value) {
let ui8 = new Uint8Array(ui16.buffer);
ui8[0] = (value >> 8) & 0xff;
ui8[1] = (value >> 0) & 0xff;
}
function writeLE(ui16, value) {
let ui8 = new Uint8Array(ui16.buffer);
ui8[0] = (value >> 0) & 0xff;
ui8[1] = (value >> 8) & 0xff;
}
// Smallest and largest SNaNs and QNaNs, with and without sign-bit set.
const NaNs = [
0x7C01, 0x7DFF, 0x7E00, 0x7FFF,
0xFC01, 0xFDFF, 0xFE00, 0xFFFF,
];
const canonicalNaN = new Uint16Array(new Float16Array([NaN]).buffer)[0];
// Load from array so that Ion doesn't treat as constants.
const True = [true, 1];
const False = [false, 0];
function f() {
let src_ui16 = new Uint16Array(1);
let dst_f16 = new Float16Array(1);
let dst_ui16 = new Uint16Array(dst_f16.buffer);
let dv = new DataView(src_ui16.buffer);
for (let i = 0; i < 100; ++i) {
let nan = NaNs[i % NaNs.length];
// Write to typed array, implicitly using native endian.
src_ui16[0] = nan;
dst_f16[0] = dv.getFloat16(0, nativeIsLittleEndian);
assertEq(dst_ui16[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is absent.
writeBE(src_ui16, nan);
dst_f16[0] = dv.getFloat16(0);
assertEq(dst_ui16[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is a constant.
writeBE(src_ui16, nan);
dst_f16[0] = dv.getFloat16(0, false);
assertEq(dst_ui16[0], canonicalNaN);
// Write and read using little endian. |isLittleEndian| parameter is a constant.
writeLE(src_ui16, nan);
dst_f16[0] = dv.getFloat16(0, true);
assertEq(dst_ui16[0], canonicalNaN);
// Write and read using big endian.
writeBE(src_ui16, nan);
dst_f16[0] = dv.getFloat16(0, False[i & 1]);
assertEq(dst_ui16[0], canonicalNaN);
// Write and read using little endian.
writeLE(src_ui16, nan);
dst_f16[0] = dv.getFloat16(0, True[i & 1]);
assertEq(dst_ui16[0], canonicalNaN);
}
}
for (let i = 0; i < 2; ++i) f();
}
testF16();
// Float32
function testF32() {
function writeBE(ui32, value) {
let ui8 = new Uint8Array(ui32.buffer);
ui8[0] = (value >> 24) & 0xff;
ui8[1] = (value >> 16) & 0xff;
ui8[2] = (value >> 8) & 0xff;
ui8[3] = (value >> 0) & 0xff;
}
function writeLE(ui32, value) {
let ui8 = new Uint8Array(ui32.buffer);
ui8[0] = (value >> 0) & 0xff;
ui8[1] = (value >> 8) & 0xff;
ui8[2] = (value >> 16) & 0xff;
ui8[3] = (value >> 24) & 0xff;
}
// Smallest and largest SNaNs and QNaNs, with and without sign-bit set.
const NaNs = [
0x7F80_0001, 0x7FBF_FFFF, 0x7FC0_0000, 0x7FFF_FFFF,
0xFF80_0001, 0xFFBF_FFFF, 0xFFC0_0000, 0xFFFF_FFFF,
];
const canonicalNaN = new Uint32Array(new Float32Array([NaN]).buffer)[0];
// Load from array so that Ion doesn't treat as constants.
const True = [true, 1];
const False = [false, 0];
function f() {
let src_ui32 = new Uint32Array(1);
let dst_f32 = new Float32Array(1);
let dst_ui32 = new Uint32Array(dst_f32.buffer);
let dv = new DataView(src_ui32.buffer);
for (let i = 0; i < 100; ++i) {
let nan = NaNs[i % NaNs.length];
// Write to typed array, implicitly using native endian.
src_ui32[0] = nan;
dst_f32[0] = dv.getFloat32(0, nativeIsLittleEndian);
assertEq(dst_ui32[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is absent.
writeBE(src_ui32, nan);
dst_f32[0] = dv.getFloat32(0);
assertEq(dst_ui32[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is a constant.
writeBE(src_ui32, nan);
dst_f32[0] = dv.getFloat32(0, false);
assertEq(dst_ui32[0], canonicalNaN);
// Write and read using little endian. |isLittleEndian| parameter is a constant.
writeLE(src_ui32, nan);
dst_f32[0] = dv.getFloat32(0, true);
assertEq(dst_ui32[0], canonicalNaN);
// Write and read using big endian.
writeBE(src_ui32, nan);
dst_f32[0] = dv.getFloat32(0, False[i & 1]);
assertEq(dst_ui32[0], canonicalNaN);
// Write and read using little endian.
writeLE(src_ui32, nan);
dst_f32[0] = dv.getFloat32(0, True[i & 1]);
assertEq(dst_ui32[0], canonicalNaN);
}
}
for (let i = 0; i < 2; ++i) f();
}
testF32();
// Float64
function testF64() {
function writeBE(ui64, value) {
let ui8 = new Uint8Array(ui64.buffer);
ui8[0] = Number((value >> 56n) & 0xffn);
ui8[1] = Number((value >> 48n) & 0xffn);
ui8[2] = Number((value >> 40n) & 0xffn);
ui8[3] = Number((value >> 32n) & 0xffn);
ui8[4] = Number((value >> 24n) & 0xffn);
ui8[5] = Number((value >> 16n) & 0xffn);
ui8[6] = Number((value >> 8n) & 0xffn);
ui8[7] = Number((value >> 0n) & 0xffn);
}
function writeLE(ui64, value) {
let ui8 = new Uint8Array(ui64.buffer);
ui8[0] = Number((value >> 0n) & 0xffn);
ui8[1] = Number((value >> 8n) & 0xffn);
ui8[2] = Number((value >> 16n) & 0xffn);
ui8[3] = Number((value >> 24n) & 0xffn);
ui8[4] = Number((value >> 32n) & 0xffn);
ui8[5] = Number((value >> 40n) & 0xffn);
ui8[6] = Number((value >> 48n) & 0xffn);
ui8[7] = Number((value >> 56n) & 0xffn);
}
// Smallest and largest SNaNs and QNaNs, with and without sign-bit set.
const NaNs = [
0x7FF0_0000_0000_0001n, 0x7FF7_FFFF_FFFF_FFFFn, 0x7FF8_0000_0000_0000n, 0x7FFF_FFFF_FFFF_FFFFn,
0xFFF0_0000_0000_0001n, 0xFFF7_FFFF_FFFF_FFFFn, 0xFFF8_0000_0000_0000n, 0xFFFF_FFFF_FFFF_FFFFn,
];
const canonicalNaN = new BigUint64Array(new Float64Array([NaN]).buffer)[0];
// Load from array so that Ion doesn't treat as constants.
const True = [true, 1];
const False = [false, 0];
function f() {
let src_ui64 = new BigUint64Array(1);
let dst_f64 = new Float64Array(1);
let dst_ui64 = new BigUint64Array(dst_f64.buffer);
let dv = new DataView(src_ui64.buffer);
for (let i = 0; i < 100; ++i) {
let nan = NaNs[i % NaNs.length];
src_ui64[0] = nan;
dst_f64[0] = dv.getFloat64(0, nativeIsLittleEndian);
assertEq(dst_ui64[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is absent.
writeBE(src_ui64, nan);
dst_f64[0] = dv.getFloat64(0);
assertEq(dst_ui64[0], canonicalNaN);
// Write and read using big endian. |isLittleEndian| parameter is a constant.
writeBE(src_ui64, nan);
dst_f64[0] = dv.getFloat64(0, false);
assertEq(dst_ui64[0], canonicalNaN);
// Write and read using little endian. |isLittleEndian| parameter is a constant.
writeLE(src_ui64, nan);
dst_f64[0] = dv.getFloat64(0, true);
assertEq(dst_ui64[0], canonicalNaN);
// Write and read using big endian.
writeBE(src_ui64, nan);
dst_f64[0] = dv.getFloat64(0, False[i & 1]);
assertEq(dst_ui64[0], canonicalNaN);
// Write and read using little endian.
writeLE(src_ui64, nan);
dst_f64[0] = dv.getFloat64(0, True[i & 1]);
assertEq(dst_ui64[0], canonicalNaN);
}
}
for (let i = 0; i < 2; ++i) f();
}
testF64();