2013-12-23 10:54:47 +00:00
|
|
|
// Copyright 2013 the V8 project authors. All rights reserved.
|
|
|
|
// Redistribution and use in source and binary forms, with or without
|
|
|
|
// modification, are permitted provided that the following conditions are
|
|
|
|
// met:
|
|
|
|
//
|
|
|
|
// * Redistributions of source code must retain the above copyright
|
|
|
|
// notice, this list of conditions and the following disclaimer.
|
|
|
|
// * Redistributions in binary form must reproduce the above
|
|
|
|
// copyright notice, this list of conditions and the following
|
|
|
|
// disclaimer in the documentation and/or other materials provided
|
|
|
|
// with the distribution.
|
|
|
|
// * Neither the name of Google Inc. nor the names of its
|
|
|
|
// contributors may be used to endorse or promote products derived
|
|
|
|
// from this software without specific prior written permission.
|
|
|
|
//
|
|
|
|
// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
|
|
|
|
// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
|
|
|
|
// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
|
|
|
|
// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
|
|
|
|
// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
|
|
|
|
// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
|
|
|
|
// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
|
|
// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
|
|
// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
|
|
// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
|
|
|
|
// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
|
|
|
2014-12-11 11:23:26 +00:00
|
|
|
// Flags: --allow-natives-syntax
|
|
|
|
|
2013-12-23 10:54:47 +00:00
|
|
|
[Math.log10, Math.log2].forEach( function(fun) {
|
|
|
|
assertTrue(isNaN(fun(NaN)));
|
|
|
|
assertTrue(isNaN(fun(fun)));
|
|
|
|
assertTrue(isNaN(fun({ toString: function() { return NaN; } })));
|
|
|
|
assertTrue(isNaN(fun({ valueOf: function() { return -1; } })));
|
|
|
|
assertTrue(isNaN(fun({ valueOf: function() { return "abc"; } })));
|
|
|
|
assertTrue(isNaN(fun(-0.1)));
|
|
|
|
assertTrue(isNaN(fun(-1)));
|
|
|
|
assertEquals("-Infinity", String(fun(0)));
|
|
|
|
assertEquals("-Infinity", String(fun(-0)));
|
|
|
|
assertEquals(0, fun(1));
|
|
|
|
assertEquals("Infinity", String(fun(Infinity)));
|
|
|
|
});
|
|
|
|
|
2014-11-20 09:37:18 +00:00
|
|
|
for (var i = -310; i <= 308; i += 0.5) {
|
|
|
|
assertEquals(i, Math.log10(Math.pow(10, i)));
|
2014-12-11 11:23:26 +00:00
|
|
|
// Square roots are tested below.
|
|
|
|
if (i != -0.5 && i != 0.5) assertEquals(i, Math.log2(Math.pow(2, i)));
|
2013-12-23 10:54:47 +00:00
|
|
|
}
|
2014-11-20 09:37:18 +00:00
|
|
|
|
|
|
|
// Test denormals.
|
|
|
|
assertEquals(-307.77759430519706, Math.log10(1.5 * Math.pow(2, -1023)));
|
2014-12-11 11:23:26 +00:00
|
|
|
|
|
|
|
// Test Math.log2(2^k) for -1074 <= k <= 1023.
|
|
|
|
var n = -1074;
|
|
|
|
// This loop covers n from -1074 to -1043
|
|
|
|
for (var lowbits = 1; lowbits <= 0x80000000; lowbits *= 2) {
|
|
|
|
var x = %_ConstructDouble(0, lowbits);
|
|
|
|
assertEquals(n, Math.log2(x));
|
|
|
|
n++;
|
|
|
|
}
|
|
|
|
// This loop covers n from -1042 to -1023
|
|
|
|
for (var hibits = 1; hibits <= 0x80000; hibits *= 2) {
|
|
|
|
var x = %_ConstructDouble(hibits, 0);
|
|
|
|
assertEquals(n, Math.log2(x));
|
|
|
|
n++;
|
|
|
|
}
|
|
|
|
// The rest of the normal values of 2^n
|
|
|
|
var x = 1;
|
|
|
|
for (var n = -1022; n <= 1023; ++n) {
|
|
|
|
var x = Math.pow(2, n);
|
|
|
|
assertEquals(n, Math.log2(x));
|
|
|
|
}
|
|
|
|
|
|
|
|
// Test special values.
|
|
|
|
// Expectation isn't exactly 1/2 because Math.SQRT2 isn't exactly sqrt(2).
|
|
|
|
assertEquals(0.5000000000000001, Math.log2(Math.SQRT2));
|
|
|
|
|
|
|
|
// Expectation isn't exactly -1/2 because Math.SQRT1_2 isn't exactly sqrt(1/2).
|
|
|
|
assertEquals(-0.4999999999999999, Math.log2(Math.SQRT1_2));
|
|
|
|
|
|
|
|
assertEquals(3.321928094887362, Math.log2(10));
|
|
|
|
assertEquals(6.643856189774724, Math.log2(100));
|
|
|
|
|
|
|
|
// Test relationships
|
|
|
|
x = 1;
|
|
|
|
for (var k = 0; k < 1000; ++k) {
|
|
|
|
var y = Math.abs(Math.log2(x) + Math.log2(1/x));
|
|
|
|
assertEqualsDelta(0, y, 1.5e-14);
|
|
|
|
x *= 1.1;
|
|
|
|
}
|
|
|
|
|
|
|
|
x = Math.pow(2, -100);
|
|
|
|
for (var k = 0; k < 1000; ++k) {
|
|
|
|
var y = Math.log2(x);
|
|
|
|
var expected = Math.log(x) / Math.LN2;
|
|
|
|
var err = Math.abs(y - expected) / expected;
|
|
|
|
assertEqualsDelta(0, err, 1e-15);
|
|
|
|
x *= 1.1;
|
|
|
|
}
|