Reland "Implement hyperbolic math functions for ES6."

BUG=v8:2938
LOG=N
R=jarin@chromium.org

Review URL: https://codereview.chromium.org/104173002

git-svn-id: http://v8.googlecode.com/svn/branches/bleeding_edge@18258 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

diff --git a/src/harmony-math.js b/src/harmony-math.js
index a4d3f2e..2bf33d6 100644 (file)
--- a/src/harmony-math.js
+++ b/src/harmony-math.js
@@ -47,13 +47,82 @@ function MathTrunc(x) {
 }
 
 
+// ES6 draft 09-27-13, section 20.2.2.30.
+function MathSinh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  // Idempotent for NaN, +/-0 and +/-Infinity.
+  if (x === 0 || !NUMBER_IS_FINITE(x)) return x;
+  return (MathExp(x) - MathExp(-x)) / 2;
+}
+
+
+// ES6 draft 09-27-13, section 20.2.2.12.
+function MathCosh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  // Idempotent for NaN and +/-Infinity.
+  if (!NUMBER_IS_FINITE(x)) return x;
+  return (MathExp(x) + MathExp(-x)) / 2;
+}
+
+
+// ES6 draft 09-27-13, section 20.2.2.33.
+function MathTanh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  // Idempotent for +/-0.
+  if (x === 0) return x;
+  // Returns +/-1 for +/-Infinity.
+  if (!NUMBER_IS_FINITE(x)) return MathSign(x);
+  var exp1 = MathExp(x);
+  var exp2 = MathExp(-x);
+  return (exp1 - exp2) / (exp1 + exp2);
+}
+
+
+// ES6 draft 09-27-13, section 20.2.2.5.
+function MathAsinh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  // Idempotent for NaN, +/-0 and +/-Infinity.
+  if (x === 0 || !NUMBER_IS_FINITE(x)) return x;
+  if (x > 0) return MathLog(x + MathSqrt(x * x + 1));
+  // This is to prevent numerical errors caused by large negative x.
+  return -MathLog(-x + MathSqrt(x * x + 1));
+}
+
+
+// ES6 draft 09-27-13, section 20.2.2.3.
+function MathAcosh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  if (x < 1) return NAN;
+  // Idempotent for NaN and +Infinity.
+  if (!NUMBER_IS_FINITE(x)) return x;
+  return MathLog(x + MathSqrt(x + 1) * MathSqrt(x - 1));
+}
+
+
+// ES6 draft 09-27-13, section 20.2.2.7.
+function MathAtanh(x) {
+  if (!IS_NUMBER(x)) x = NonNumberToNumber(x);
+  // Idempotent for +/-0.
+  if (x === 0) return x;
+  // Returns NaN for NaN and +/- Infinity.
+  if (!NUMBER_IS_FINITE(x)) return NAN;
+  return 0.5 * MathLog((1 + x) / (1 - x));
+}
+
+
 function ExtendMath() {
   %CheckIsBootstrapping();
 
   // Set up the non-enumerable functions on the Math object.
   InstallFunctions($Math, DONT_ENUM, $Array(
     "sign", MathSign,
-    "trunc", MathTrunc
+    "trunc", MathTrunc,
+    "sinh", MathSinh,
+    "cosh", MathCosh,
+    "tanh", MathTanh,
+    "asinh", MathAsinh,
+    "acosh", MathAcosh,
+    "atanh", MathAtanh
   ));
 }
 

diff --git a/test/mjsunit/harmony/math-hyperbolic.js b/test/mjsunit/harmony/math-hyperbolic.js
new file mode 100644 (file)
index 0000000..604448d
--- /dev/null
+++ b/test/mjsunit/harmony/math-hyperbolic.js
@@ -0,0 +1,132 @@
+// 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.
+
+// Flags: --harmony-maths
+
+[Math.sinh, Math.cosh, Math.tanh, Math.asinh, Math.acosh, Math.atanh].
+    forEach(function(fun) {
+  assertTrue(isNaN(fun(NaN)));
+  assertTrue(isNaN(fun("abc")));
+  assertTrue(isNaN(fun({})));
+  assertEquals(fun(0), fun([]));
+  assertTrue(isNaN(fun([1, 1])));
+  assertEquals(fun(1.11), fun({ toString: function() { return "1.11"; } }));
+  assertEquals(fun(-3.1), fun({ toString: function() { return -3.1; } }));
+  assertEquals(fun(-1.1), fun({ valueOf: function() { return "-1.1"; } }));
+  assertEquals(fun(3.11), fun({ valueOf: function() { return 3.11; } }));
+});
+
+
+function test_id(fun, rev, value) {
+  assertEqualsDelta(1, rev(fun(value))/value, 1E-7);
+}
+
+[Math.PI, 2, 5, 1E-5, 0.3].forEach(function(x) {
+  test_id(Math.sinh, Math.asinh, x);
+  test_id(Math.sinh, Math.asinh, -x);
+  test_id(Math.cosh, Math.acosh, x);
+  test_id(Math.tanh, Math.atanh, x);
+  test_id(Math.tanh, Math.atanh, -x);
+});
+
+
+[Math.sinh, Math.asinh, Math.tanh, Math.atanh].forEach(function(fun) {
+  assertEquals("-Infinity", String(1/fun(-0)));
+  assertEquals("Infinity", String(1/fun(0)));
+});
+
+
+[Math.sinh, Math.asinh, Math.cosh].forEach(function(fun) {
+  assertEquals("-Infinity", String(fun(-Infinity)));
+  assertEquals("Infinity", String(fun(Infinity)));
+  assertEquals("-Infinity", String(fun("-Infinity")));
+  assertEquals("Infinity", String(fun("Infinity")));
+});
+
+
+assertEquals("-Infinity", String(Math.atanh(-1)));
+assertEquals("Infinity", String(Math.atanh(1)));
+
+// Math.atanh(x) is NaN for |x| > 1 and NaN
+[1.000000000001, Math.PI, 10000000, 2, Infinity, NaN].forEach(function(x) {
+  assertTrue(isNaN(Math.atanh(-x)));
+  assertTrue(isNaN(Math.atanh(x)));
+});
+
+
+assertEquals(1, Math.tanh(Infinity));
+assertEquals(-1, Math.tanh(-Infinity));
+assertEquals(1, Math.cosh(0));
+assertEquals(1, Math.cosh(-0));
+
+assertEquals(0, Math.acosh(1));
+assertEquals("Infinity", String(Math.acosh(Infinity)));
+
+// Math.acosh(x) is NaN for x < 1
+[0.99999999999, 0.2, -1000, 0, -0].forEach(function(x) {
+  assertTrue(isNaN(Math.acosh(x)));
+});
+
+
+// Some random samples.
+assertEqualsDelta(0.5210953054937, Math.sinh(0.5), 1E-12);
+assertEqualsDelta(74.203210577788, Math.sinh(5), 1E-12);
+assertEqualsDelta(-0.5210953054937, Math.sinh(-0.5), 1E-12);
+assertEqualsDelta(-74.203210577788, Math.sinh(-5), 1E-12);
+
+assertEqualsDelta(1.1276259652063, Math.cosh(0.5), 1E-12);
+assertEqualsDelta(74.209948524787, Math.cosh(5), 1E-12);
+assertEqualsDelta(1.1276259652063, Math.cosh(-0.5), 1E-12);
+assertEqualsDelta(74.209948524787, Math.cosh(-5), 1E-12);
+
+assertEqualsDelta(0.4621171572600, Math.tanh(0.5), 1E-12);
+assertEqualsDelta(0.9999092042625, Math.tanh(5), 1E-12);
+assertEqualsDelta(-0.4621171572600, Math.tanh(-0.5), 1E-12);
+assertEqualsDelta(-0.9999092042625, Math.tanh(-5), 1E-12);
+
+assertEqualsDelta(0.4812118250596, Math.asinh(0.5), 1E-12);
+assertEqualsDelta(2.3124383412727, Math.asinh(5), 1E-12);
+assertEqualsDelta(-0.4812118250596, Math.asinh(-0.5), 1E-12);
+assertEqualsDelta(-2.3124383412727, Math.asinh(-5), 1E-12);
+
+assertEqualsDelta(0.9624236501192, Math.acosh(1.5), 1E-12);
+assertEqualsDelta(2.2924316695612, Math.acosh(5), 1E-12);
+assertEqualsDelta(0.4435682543851, Math.acosh(1.1), 1E-12);
+assertEqualsDelta(1.3169578969248, Math.acosh(2), 1E-12);
+
+assertEqualsDelta(0.5493061443341, Math.atanh(0.5), 1E-12);
+assertEqualsDelta(0.1003353477311, Math.atanh(0.1), 1E-12);
+assertEqualsDelta(-0.5493061443341, Math.atanh(-0.5), 1E-12);
+assertEqualsDelta(-0.1003353477311, Math.atanh(-0.1), 1E-12);
+
+[0, 1E-50, 1E-10, 1E10, 1E50, 1E100, 1E150].forEach(function(x) {
+  assertEqualsDelta(Math.asinh(x), -Math.asinh(-x), 1E-12);
+});
+
+[1-(1E-16), 0, 1E-10, 1E-50].forEach(function(x) {
+  assertEqualsDelta(Math.atanh(x), -Math.atanh(-x), 1E-12);
+});