diff -r 000000000000 -r 6474c204b198 js/src/jsmath.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/js/src/jsmath.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,1509 @@
+/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 4 -*-
+ * vim: set ts=8 sts=4 et sw=4 tw=99:
+ * 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
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+/*
+ * JS math package.
+ */
+
+#include "jsmath.h"
+
+#include "mozilla/Constants.h"
+#include "mozilla/FloatingPoint.h"
+#include "mozilla/MathAlgorithms.h"
+#include "mozilla/MemoryReporting.h"
+
+#include <algorithm>  // for std::max
+#include <fcntl.h>
+
+#ifdef XP_UNIX
+# include <unistd.h>
+#endif
+
+#include "jsapi.h"
+#include "jsatom.h"
+#include "jscntxt.h"
+#include "jscompartment.h"
+#include "jslibmath.h"
+#include "jstypes.h"
+#include "prmjtime.h"
+
+#include "jsobjinlines.h"
+
+using namespace js;
+
+using mozilla::Abs;
+using mozilla::NumberEqualsInt32;
+using mozilla::NumberIsInt32;
+using mozilla::ExponentComponent;
+using mozilla::FloatingPoint;
+using mozilla::IsFinite;
+using mozilla::IsInfinite;
+using mozilla::IsNaN;
+using mozilla::IsNegative;
+using mozilla::IsNegativeZero;
+using mozilla::PositiveInfinity;
+using mozilla::NegativeInfinity;
+using JS::ToNumber;
+using JS::GenericNaN;
+
+static const JSConstDoubleSpec math_constants[] = {
+    {M_E,       "E",            0, {0,0,0}},
+    {M_LOG2E,   "LOG2E",        0, {0,0,0}},
+    {M_LOG10E,  "LOG10E",       0, {0,0,0}},
+    {M_LN2,     "LN2",          0, {0,0,0}},
+    {M_LN10,    "LN10",         0, {0,0,0}},
+    {M_PI,      "PI",           0, {0,0,0}},
+    {M_SQRT2,   "SQRT2",        0, {0,0,0}},
+    {M_SQRT1_2, "SQRT1_2",      0, {0,0,0}},
+    {0,0,0,{0,0,0}}
+};
+
+MathCache::MathCache() {
+    memset(table, 0, sizeof(table));
+
+    /* See comments in lookup(). */
+    JS_ASSERT(IsNegativeZero(-0.0));
+    JS_ASSERT(!IsNegativeZero(+0.0));
+    JS_ASSERT(hash(-0.0) != hash(+0.0));
+}
+
+size_t
+MathCache::sizeOfIncludingThis(mozilla::MallocSizeOf mallocSizeOf)
+{
+    return mallocSizeOf(this);
+}
+
+const Class js::MathClass = {
+    js_Math_str,
+    JSCLASS_HAS_CACHED_PROTO(JSProto_Math),
+    JS_PropertyStub,         /* addProperty */
+    JS_DeletePropertyStub,   /* delProperty */
+    JS_PropertyStub,         /* getProperty */
+    JS_StrictPropertyStub,   /* setProperty */
+    JS_EnumerateStub,
+    JS_ResolveStub,
+    JS_ConvertStub
+};
+
+bool
+js_math_abs(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    double z = Abs(x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+#if defined(SOLARIS) && defined(__GNUC__)
+#define ACOS_IF_OUT_OF_RANGE(x) if (x < -1 || 1 < x) return GenericNaN();
+#else
+#define ACOS_IF_OUT_OF_RANGE(x)
+#endif
+
+double
+js::math_acos_impl(MathCache *cache, double x)
+{
+    ACOS_IF_OUT_OF_RANGE(x);
+    return cache->lookup(acos, x);
+}
+
+double
+js::math_acos_uncached(double x)
+{
+    ACOS_IF_OUT_OF_RANGE(x);
+    return acos(x);
+}
+
+#undef ACOS_IF_OUT_OF_RANGE
+
+bool
+js::math_acos(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_acos_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+#if defined(SOLARIS) && defined(__GNUC__)
+#define ASIN_IF_OUT_OF_RANGE(x) if (x < -1 || 1 < x) return GenericNaN();
+#else
+#define ASIN_IF_OUT_OF_RANGE(x)
+#endif
+
+double
+js::math_asin_impl(MathCache *cache, double x)
+{
+    ASIN_IF_OUT_OF_RANGE(x);
+    return cache->lookup(asin, x);
+}
+
+double
+js::math_asin_uncached(double x)
+{
+    ASIN_IF_OUT_OF_RANGE(x);
+    return asin(x);
+}
+
+#undef ASIN_IF_OUT_OF_RANGE
+
+bool
+js::math_asin(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_asin_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+double
+js::math_atan_impl(MathCache *cache, double x)
+{
+    return cache->lookup(atan, x);
+}
+
+double
+js::math_atan_uncached(double x)
+{
+    return atan(x);
+}
+
+bool
+js::math_atan(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_atan_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+double
+js::ecmaAtan2(double y, double x)
+{
+#if defined(_MSC_VER)
+    /*
+     * MSVC's atan2 does not yield the result demanded by ECMA when both x
+     * and y are infinite.
+     * - The result is a multiple of pi/4.
+     * - The sign of y determines the sign of the result.
+     * - The sign of x determines the multiplicator, 1 or 3.
+     */
+    if (IsInfinite(y) && IsInfinite(x)) {
+        double z = js_copysign(M_PI / 4, y);
+        if (x < 0)
+            z *= 3;
+        return z;
+    }
+#endif
+
+#if defined(SOLARIS) && defined(__GNUC__)
+    if (y == 0) {
+        if (IsNegativeZero(x))
+            return js_copysign(M_PI, y);
+        if (x == 0)
+            return y;
+    }
+#endif
+    return atan2(y, x);
+}
+
+bool
+js::math_atan2(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    double y;
+    if (!ToNumber(cx, args.get(0), &y))
+        return false;
+
+    double x;
+    if (!ToNumber(cx, args.get(1), &x))
+        return false;
+
+    double z = ecmaAtan2(y, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+double
+js::math_ceil_impl(double x)
+{
+#ifdef __APPLE__
+    if (x < 0 && x > -1.0)
+        return js_copysign(0, -1);
+#endif
+    return ceil(x);
+}
+
+bool
+js::math_ceil(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    double z = math_ceil_impl(x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+bool
+js::math_clz32(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setInt32(32);
+        return true;
+    }
+
+    uint32_t n;
+    if (!ToUint32(cx, args[0], &n))
+        return false;
+
+    if (n == 0) {
+        args.rval().setInt32(32);
+        return true;
+    }
+
+    args.rval().setInt32(mozilla::CountLeadingZeroes32(n));
+    return true;
+}
+
+double
+js::math_cos_impl(MathCache *cache, double x)
+{
+    return cache->lookup(cos, x);
+}
+
+double
+js::math_cos_uncached(double x)
+{
+    return cos(x);
+}
+
+bool
+js::math_cos(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_cos_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+#ifdef _WIN32
+#define EXP_IF_OUT_OF_RANGE(x)                  \
+    if (!IsNaN(x)) {                            \
+        if (x == PositiveInfinity<double>())    \
+            return PositiveInfinity<double>();  \
+        if (x == NegativeInfinity<double>())    \
+            return 0.0;                         \
+    }
+#else
+#define EXP_IF_OUT_OF_RANGE(x)
+#endif
+
+double
+js::math_exp_impl(MathCache *cache, double x)
+{
+    EXP_IF_OUT_OF_RANGE(x);
+    return cache->lookup(exp, x);
+}
+
+double
+js::math_exp_uncached(double x)
+{
+    EXP_IF_OUT_OF_RANGE(x);
+    return exp(x);
+}
+
+#undef EXP_IF_OUT_OF_RANGE
+
+bool
+js::math_exp(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_exp_impl(mathCache, x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+double
+js::math_floor_impl(double x)
+{
+    return floor(x);
+}
+
+bool
+js::math_floor(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    double z = math_floor_impl(x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+bool
+js::math_imul(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    uint32_t a = 0, b = 0;
+    if (args.hasDefined(0) && !ToUint32(cx, args[0], &a))
+        return false;
+    if (args.hasDefined(1) && !ToUint32(cx, args[1], &b))
+        return false;
+
+    uint32_t product = a * b;
+    args.rval().setInt32(product > INT32_MAX
+                         ? int32_t(INT32_MIN + (product - INT32_MAX - 1))
+                         : int32_t(product));
+    return true;
+}
+
+// Implements Math.fround (20.2.2.16) up to step 3
+bool
+js::RoundFloat32(JSContext *cx, Handle<Value> v, float *out)
+{
+    double d;
+    bool success = ToNumber(cx, v, &d);
+    *out = static_cast<float>(d);
+    return success;
+}
+
+bool
+js::math_fround(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    float f;
+    if (!RoundFloat32(cx, args[0], &f))
+        return false;
+
+    args.rval().setDouble(static_cast<double>(f));
+    return true;
+}
+
+#if defined(SOLARIS) && defined(__GNUC__)
+#define LOG_IF_OUT_OF_RANGE(x) if (x < 0) return GenericNaN();
+#else
+#define LOG_IF_OUT_OF_RANGE(x)
+#endif
+
+double
+js::math_log_impl(MathCache *cache, double x)
+{
+    LOG_IF_OUT_OF_RANGE(x);
+    return cache->lookup(log, x);
+}
+
+double
+js::math_log_uncached(double x)
+{
+    LOG_IF_OUT_OF_RANGE(x);
+    return log(x);
+}
+
+#undef LOG_IF_OUT_OF_RANGE
+
+bool
+js::math_log(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_log_impl(mathCache, x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+bool
+js_math_max(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    double maxval = NegativeInfinity<double>();
+    for (unsigned i = 0; i < args.length(); i++) {
+        double x;
+        if (!ToNumber(cx, args[i], &x))
+            return false;
+        // Math.max(num, NaN) => NaN, Math.max(-0, +0) => +0
+        if (x > maxval || IsNaN(x) || (x == maxval && IsNegative(maxval)))
+            maxval = x;
+    }
+    args.rval().setNumber(maxval);
+    return true;
+}
+
+bool
+js_math_min(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    double minval = PositiveInfinity<double>();
+    for (unsigned i = 0; i < args.length(); i++) {
+        double x;
+        if (!ToNumber(cx, args[i], &x))
+            return false;
+        // Math.min(num, NaN) => NaN, Math.min(-0, +0) => -0
+        if (x < minval || IsNaN(x) || (x == minval && IsNegativeZero(x)))
+            minval = x;
+    }
+    args.rval().setNumber(minval);
+    return true;
+}
+
+// Disable PGO for Math.pow() and related functions (see bug 791214).
+#if defined(_MSC_VER)
+# pragma optimize("g", off)
+#endif
+double
+js::powi(double x, int y)
+{
+    unsigned n = (y < 0) ? -y : y;
+    double m = x;
+    double p = 1;
+    while (true) {
+        if ((n & 1) != 0) p *= m;
+        n >>= 1;
+        if (n == 0) {
+            if (y < 0) {
+                // Unfortunately, we have to be careful when p has reached
+                // infinity in the computation, because sometimes the higher
+                // internal precision in the pow() implementation would have
+                // given us a finite p. This happens very rarely.
+
+                double result = 1.0 / p;
+                return (result == 0 && IsInfinite(p))
+                       ? pow(x, static_cast<double>(y))  // Avoid pow(double, int).
+                       : result;
+            }
+
+            return p;
+        }
+        m *= m;
+    }
+}
+#if defined(_MSC_VER)
+# pragma optimize("", on)
+#endif
+
+// Disable PGO for Math.pow() and related functions (see bug 791214).
+#if defined(_MSC_VER)
+# pragma optimize("g", off)
+#endif
+double
+js::ecmaPow(double x, double y)
+{
+    /*
+     * Use powi if the exponent is an integer-valued double. We don't have to
+     * check for NaN since a comparison with NaN is always false.
+     */
+    int32_t yi;
+    if (NumberEqualsInt32(y, &yi))
+        return powi(x, yi);
+
+    /*
+     * Because C99 and ECMA specify different behavior for pow(),
+     * we need to wrap the libm call to make it ECMA compliant.
+     */
+    if (!IsFinite(y) && (x == 1.0 || x == -1.0))
+        return GenericNaN();
+
+    /* pow(x, +-0) is always 1, even for x = NaN (MSVC gets this wrong). */
+    if (y == 0)
+        return 1;
+
+    /*
+     * Special case for square roots. Note that pow(x, 0.5) != sqrt(x)
+     * when x = -0.0, so we have to guard for this.
+     */
+    if (IsFinite(x) && x != 0.0) {
+        if (y == 0.5)
+            return sqrt(x);
+        if (y == -0.5)
+            return 1.0 / sqrt(x);
+    }
+    return pow(x, y);
+}
+#if defined(_MSC_VER)
+# pragma optimize("", on)
+#endif
+
+// Disable PGO for Math.pow() and related functions (see bug 791214).
+#if defined(_MSC_VER)
+# pragma optimize("g", off)
+#endif
+bool
+js_math_pow(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    double x;
+    if (!ToNumber(cx, args.get(0), &x))
+        return false;
+
+    double y;
+    if (!ToNumber(cx, args.get(1), &y))
+        return false;
+
+    double z = ecmaPow(x, y);
+    args.rval().setNumber(z);
+    return true;
+}
+#if defined(_MSC_VER)
+# pragma optimize("", on)
+#endif
+
+static uint64_t
+random_generateSeed()
+{
+    union {
+        uint8_t     u8[8];
+        uint32_t    u32[2];
+        uint64_t    u64;
+    } seed;
+    seed.u64 = 0;
+
+#if defined(XP_WIN)
+    /*
+     * Our PRNG only uses 48 bits, so calling rand_s() twice to get 64 bits is
+     * probably overkill.
+     */
+    rand_s(&seed.u32[0]);
+#elif defined(XP_UNIX)
+    /*
+     * In the unlikely event we can't read /dev/urandom, there's not much we can
+     * do, so just mix in the fd error code and the current time.
+     */
+    int fd = open("/dev/urandom", O_RDONLY);
+    MOZ_ASSERT(fd >= 0, "Can't open /dev/urandom");
+    if (fd >= 0) {
+        read(fd, seed.u8, mozilla::ArrayLength(seed.u8));
+        close(fd);
+    }
+    seed.u32[0] ^= fd;
+#else
+# error "Platform needs to implement random_generateSeed()"
+#endif
+
+    seed.u32[1] ^= PRMJ_Now();
+    return seed.u64;
+}
+
+static const uint64_t RNG_MULTIPLIER = 0x5DEECE66DLL;
+static const uint64_t RNG_ADDEND = 0xBLL;
+static const uint64_t RNG_MASK = (1LL << 48) - 1;
+static const double RNG_DSCALE = double(1LL << 53);
+
+/*
+ * Math.random() support, lifted from java.util.Random.java.
+ */
+static void
+random_initState(uint64_t *rngState)
+{
+    /* Our PRNG only uses 48 bits, so squeeze our entropy into those bits. */
+    uint64_t seed = random_generateSeed();
+    seed ^= (seed >> 16);
+    *rngState = (seed ^ RNG_MULTIPLIER) & RNG_MASK;
+}
+
+uint64_t
+random_next(uint64_t *rngState, int bits)
+{
+    MOZ_ASSERT((*rngState & 0xffff000000000000ULL) == 0, "Bad rngState");
+    MOZ_ASSERT(bits > 0 && bits <= 48, "bits is out of range");
+
+    if (*rngState == 0) {
+        random_initState(rngState);
+    }
+
+    uint64_t nextstate = *rngState * RNG_MULTIPLIER;
+    nextstate += RNG_ADDEND;
+    nextstate &= RNG_MASK;
+    *rngState = nextstate;
+    return nextstate >> (48 - bits);
+}
+
+static inline double
+random_nextDouble(JSContext *cx)
+{
+    uint64_t *rng = &cx->compartment()->rngState;
+    return double((random_next(rng, 26) << 27) + random_next(rng, 27)) / RNG_DSCALE;
+}
+
+double
+math_random_no_outparam(JSContext *cx)
+{
+    /* Calculate random without memory traffic, for use in the JITs. */
+    return random_nextDouble(cx);
+}
+
+bool
+js_math_random(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+    double z = random_nextDouble(cx);
+    args.rval().setDouble(z);
+    return true;
+}
+
+double
+js::math_round_impl(double x)
+{
+    int32_t ignored;
+    if (NumberIsInt32(x, &ignored))
+        return x;
+
+    /* Some numbers are so big that adding 0.5 would give the wrong number. */
+    if (ExponentComponent(x) >= int_fast16_t(FloatingPoint<double>::ExponentShift))
+        return x;
+
+    return js_copysign(floor(x + 0.5), x);
+}
+
+float
+js::math_roundf_impl(float x)
+{
+    int32_t ignored;
+    if (NumberIsInt32(x, &ignored))
+        return x;
+
+    /* Some numbers are so big that adding 0.5 would give the wrong number. */
+    if (ExponentComponent(x) >= int_fast16_t(FloatingPoint<float>::ExponentShift))
+        return x;
+
+    return js_copysign(floorf(x + 0.5f), x);
+}
+
+bool /* ES5 15.8.2.15. */
+js::math_round(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    double z = math_round_impl(x);
+    args.rval().setNumber(z);
+    return true;
+}
+
+double
+js::math_sin_impl(MathCache *cache, double x)
+{
+    return cache->lookup(sin, x);
+}
+
+double
+js::math_sin_uncached(double x)
+{
+    return sin(x);
+}
+
+bool
+js::math_sin(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_sin_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+bool
+js_math_sqrt(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = mathCache->lookup(sqrt, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+double
+js::math_tan_impl(MathCache *cache, double x)
+{
+    return cache->lookup(tan, x);
+}
+
+double
+js::math_tan_uncached(double x)
+{
+    return tan(x);
+}
+
+bool
+js::math_tan(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    if (args.length() == 0) {
+        args.rval().setNaN();
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+
+    double z = math_tan_impl(mathCache, x);
+    args.rval().setDouble(z);
+    return true;
+}
+
+
+typedef double (*UnaryMathFunctionType)(MathCache *cache, double);
+
+template <UnaryMathFunctionType F>
+static bool math_function(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+    if (args.length() == 0) {
+        args.rval().setNumber(GenericNaN());
+        return true;
+    }
+
+    double x;
+    if (!ToNumber(cx, args[0], &x))
+        return false;
+
+    MathCache *mathCache = cx->runtime()->getMathCache(cx);
+    if (!mathCache)
+        return false;
+    double z = F(mathCache, x);
+    args.rval().setNumber(z);
+
+    return true;
+}
+
+
+
+double
+js::math_log10_impl(MathCache *cache, double x)
+{
+    return cache->lookup(log10, x);
+}
+
+double
+js::math_log10_uncached(double x)
+{
+    return log10(x);
+}
+
+bool
+js::math_log10(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_log10_impl>(cx, argc, vp);
+}
+
+#if !HAVE_LOG2
+double log2(double x)
+{
+    return log(x) / M_LN2;
+}
+#endif
+
+double
+js::math_log2_impl(MathCache *cache, double x)
+{
+    return cache->lookup(log2, x);
+}
+
+double
+js::math_log2_uncached(double x)
+{
+    return log2(x);
+}
+
+bool
+js::math_log2(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_log2_impl>(cx, argc, vp);
+}
+
+#if !HAVE_LOG1P
+double log1p(double x)
+{
+    if (fabs(x) < 1e-4) {
+        /*
+         * Use Taylor approx. log(1 + x) = x - x^2 / 2 + x^3 / 3 - x^4 / 4 with error x^5 / 5
+         * Since |x| < 10^-4, |x|^5 < 10^-20, relative error less than 10^-16
+         */
+        double z = -(x * x * x * x) / 4 + (x * x * x) / 3 - (x * x) / 2 + x;
+        return z;
+    } else {
+        /* For other large enough values of x use direct computation */
+        return log(1.0 + x);
+    }
+}
+#endif
+
+#ifdef __APPLE__
+// Ensure that log1p(-0) is -0.
+#define LOG1P_IF_OUT_OF_RANGE(x) if (x == 0) return x;
+#else
+#define LOG1P_IF_OUT_OF_RANGE(x)
+#endif
+
+double
+js::math_log1p_impl(MathCache *cache, double x)
+{
+    LOG1P_IF_OUT_OF_RANGE(x);
+    return cache->lookup(log1p, x);
+}
+
+double
+js::math_log1p_uncached(double x)
+{
+    LOG1P_IF_OUT_OF_RANGE(x);
+    return log1p(x);
+}
+
+#undef LOG1P_IF_OUT_OF_RANGE
+
+bool
+js::math_log1p(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_log1p_impl>(cx, argc, vp);
+}
+
+#if !HAVE_EXPM1
+double expm1(double x)
+{
+    /* Special handling for -0 */
+    if (x == 0.0)
+        return x;
+
+    if (fabs(x) < 1e-5) {
+        /*
+         * Use Taylor approx. exp(x) - 1 = x + x^2 / 2 + x^3 / 6 with error x^4 / 24
+         * Since |x| < 10^-5, |x|^4 < 10^-20, relative error less than 10^-15
+         */
+        double z = (x * x * x) / 6 + (x * x) / 2 + x;
+        return z;
+    } else {
+        /* For other large enough values of x use direct computation */
+        return exp(x) - 1.0;
+    }
+}
+#endif
+
+double
+js::math_expm1_impl(MathCache *cache, double x)
+{
+    return cache->lookup(expm1, x);
+}
+
+double
+js::math_expm1_uncached(double x)
+{
+    return expm1(x);
+}
+
+bool
+js::math_expm1(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_expm1_impl>(cx, argc, vp);
+}
+
+#if !HAVE_SQRT1PM1
+/* This algorithm computes sqrt(1+x)-1 for small x */
+double sqrt1pm1(double x)
+{
+    if (fabs(x) > 0.75)
+        return sqrt(1 + x) - 1;
+
+    return expm1(log1p(x) / 2);
+}
+#endif
+
+
+double
+js::math_cosh_impl(MathCache *cache, double x)
+{
+    return cache->lookup(cosh, x);
+}
+
+double
+js::math_cosh_uncached(double x)
+{
+    return cosh(x);
+}
+
+bool
+js::math_cosh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_cosh_impl>(cx, argc, vp);
+}
+
+double
+js::math_sinh_impl(MathCache *cache, double x)
+{
+    return cache->lookup(sinh, x);
+}
+
+double
+js::math_sinh_uncached(double x)
+{
+    return sinh(x);
+}
+
+bool
+js::math_sinh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_sinh_impl>(cx, argc, vp);
+}
+
+double
+js::math_tanh_impl(MathCache *cache, double x)
+{
+    return cache->lookup(tanh, x);
+}
+
+double
+js::math_tanh_uncached(double x)
+{
+    return tanh(x);
+}
+
+bool
+js::math_tanh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_tanh_impl>(cx, argc, vp);
+}
+
+#if !HAVE_ACOSH
+double acosh(double x)
+{
+    const double SQUARE_ROOT_EPSILON = sqrt(std::numeric_limits<double>::epsilon());
+
+    if ((x - 1) >= SQUARE_ROOT_EPSILON) {
+        if (x > 1 / SQUARE_ROOT_EPSILON) {
+            /*
+             * http://functions.wolfram.com/ElementaryFunctions/ArcCosh/06/01/06/01/0001/
+             * approximation by laurent series in 1/x at 0+ order from -1 to 0
+             */
+            return log(x) + M_LN2;
+        } else if (x < 1.5) {
+            // This is just a rearrangement of the standard form below
+            // devised to minimize loss of precision when x ~ 1:
+            double y = x - 1;
+            return log1p(y + sqrt(y * y + 2 * y));
+        } else {
+            // http://functions.wolfram.com/ElementaryFunctions/ArcCosh/02/
+            return log(x + sqrt(x * x - 1));
+        }
+    } else {
+        // see http://functions.wolfram.com/ElementaryFunctions/ArcCosh/06/01/04/01/0001/
+        double y = x - 1;
+        // approximation by taylor series in y at 0 up to order 2.
+        // If x is less than 1, sqrt(2 * y) is NaN and the result is NaN.
+        return sqrt(2 * y) * (1 - y / 12 + 3 * y * y / 160);
+    }
+}
+#endif
+
+double
+js::math_acosh_impl(MathCache *cache, double x)
+{
+    return cache->lookup(acosh, x);
+}
+
+double
+js::math_acosh_uncached(double x)
+{
+    return acosh(x);
+}
+
+bool
+js::math_acosh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_acosh_impl>(cx, argc, vp);
+}
+
+#if !HAVE_ASINH
+// Bug 899712 - gcc incorrectly rewrites -asinh(-x) to asinh(x) when overriding
+// asinh.
+static double my_asinh(double x)
+{
+    const double SQUARE_ROOT_EPSILON = sqrt(std::numeric_limits<double>::epsilon());
+    const double FOURTH_ROOT_EPSILON = sqrt(SQUARE_ROOT_EPSILON);
+
+    if (x >= FOURTH_ROOT_EPSILON) {
+        if (x > 1 / SQUARE_ROOT_EPSILON)
+            // http://functions.wolfram.com/ElementaryFunctions/ArcSinh/06/01/06/01/0001/
+            // approximation by laurent series in 1/x at 0+ order from -1 to 1
+            return M_LN2 + log(x) + 1 / (4 * x * x);
+        else if (x < 0.5)
+            return log1p(x + sqrt1pm1(x * x));
+        else
+            return log(x + sqrt(x * x + 1));
+    } else if (x <= -FOURTH_ROOT_EPSILON) {
+        return -my_asinh(-x);
+    } else {
+        // http://functions.wolfram.com/ElementaryFunctions/ArcSinh/06/01/03/01/0001/
+        // approximation by taylor series in x at 0 up to order 2
+        double result = x;
+
+        if (fabs(x) >= SQUARE_ROOT_EPSILON) {
+            double x3 = x * x * x;
+            // approximation by taylor series in x at 0 up to order 4
+            result -= x3 / 6;
+        }
+
+        return result;
+    }
+}
+#endif
+
+double
+js::math_asinh_impl(MathCache *cache, double x)
+{
+#ifdef HAVE_ASINH
+    return cache->lookup(asinh, x);
+#else
+    return cache->lookup(my_asinh, x);
+#endif
+}
+
+double
+js::math_asinh_uncached(double x)
+{
+#ifdef HAVE_ASINH
+    return asinh(x);
+#else
+    return my_asinh(x);
+#endif
+}
+
+bool
+js::math_asinh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_asinh_impl>(cx, argc, vp);
+}
+
+#if !HAVE_ATANH
+double atanh(double x)
+{
+    const double EPSILON = std::numeric_limits<double>::epsilon();
+    const double SQUARE_ROOT_EPSILON = sqrt(EPSILON);
+    const double FOURTH_ROOT_EPSILON = sqrt(SQUARE_ROOT_EPSILON);
+
+    if (fabs(x) >= FOURTH_ROOT_EPSILON) {
+        // http://functions.wolfram.com/ElementaryFunctions/ArcTanh/02/
+        if (fabs(x) < 0.5)
+            return (log1p(x) - log1p(-x)) / 2;
+
+        return log((1 + x) / (1 - x)) / 2;
+    } else {
+        // http://functions.wolfram.com/ElementaryFunctions/ArcTanh/06/01/03/01/
+        // approximation by taylor series in x at 0 up to order 2
+        double result = x;
+
+        if (fabs(x) >= SQUARE_ROOT_EPSILON) {
+            double x3 = x * x * x;
+            result += x3 / 3;
+        }
+
+        return result;
+    }
+}
+#endif
+
+double
+js::math_atanh_impl(MathCache *cache, double x)
+{
+    return cache->lookup(atanh, x);
+}
+
+double
+js::math_atanh_uncached(double x)
+{
+    return atanh(x);
+}
+
+bool
+js::math_atanh(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_atanh_impl>(cx, argc, vp);
+}
+
+/* Consistency wrapper for platform deviations in hypot() */
+double
+js::ecmaHypot(double x, double y)
+{
+#ifdef XP_WIN
+    /*
+     * Workaround MS hypot bug, where hypot(Infinity, NaN or Math.MIN_VALUE)
+     * is NaN, not Infinity.
+     */
+    if (mozilla::IsInfinite(x) || mozilla::IsInfinite(y)) {
+        return mozilla::PositiveInfinity<double>();
+    }
+#endif
+    return hypot(x, y);
+}
+
+bool
+js::math_hypot(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+
+    // IonMonkey calls the system hypot function directly if two arguments are
+    // given. Do that here as well to get the same results.
+    if (args.length() == 2) {
+        double x, y;
+        if (!ToNumber(cx, args[0], &x))
+            return false;
+        if (!ToNumber(cx, args[1], &y))
+            return false;
+
+        double result = ecmaHypot(x, y);
+        args.rval().setNumber(result);
+        return true;
+    }
+
+    bool isInfinite = false;
+    bool isNaN = false;
+
+    double scale = 0;
+    double sumsq = 1;
+
+    for (unsigned i = 0; i < args.length(); i++) {
+        double x;
+        if (!ToNumber(cx, args[i], &x))
+            return false;
+
+        isInfinite |= mozilla::IsInfinite(x);
+        isNaN |= mozilla::IsNaN(x);
+
+        double xabs = mozilla::Abs(x);
+
+        if (scale < xabs) {
+            sumsq = 1 + sumsq * (scale / xabs) * (scale / xabs);
+            scale = xabs;
+        } else if (scale != 0) {
+            sumsq += (xabs / scale) * (xabs / scale);
+        }
+    }
+
+    double result = isInfinite ? PositiveInfinity<double>() :
+                    isNaN ? GenericNaN() :
+                    scale * sqrt(sumsq);
+    args.rval().setNumber(result);
+    return true;
+}
+
+#if !HAVE_TRUNC
+double trunc(double x)
+{
+    return x > 0 ? floor(x) : ceil(x);
+}
+#endif
+
+double
+js::math_trunc_impl(MathCache *cache, double x)
+{
+    return cache->lookup(trunc, x);
+}
+
+double
+js::math_trunc_uncached(double x)
+{
+    return trunc(x);
+}
+
+bool
+js::math_trunc(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_trunc_impl>(cx, argc, vp);
+}
+
+static double sign(double x)
+{
+    if (mozilla::IsNaN(x))
+        return GenericNaN();
+
+    return x == 0 ? x : x < 0 ? -1 : 1;
+}
+
+double
+js::math_sign_impl(MathCache *cache, double x)
+{
+    return cache->lookup(sign, x);
+}
+
+double
+js::math_sign_uncached(double x)
+{
+    return sign(x);
+}
+
+bool
+js::math_sign(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_sign_impl>(cx, argc, vp);
+}
+
+#if !HAVE_CBRT
+double cbrt(double x)
+{
+    if (x > 0) {
+        return pow(x, 1.0 / 3.0);
+    } else if (x == 0) {
+        return x;
+    } else {
+        return -pow(-x, 1.0 / 3.0);
+    }
+}
+#endif
+
+double
+js::math_cbrt_impl(MathCache *cache, double x)
+{
+    return cache->lookup(cbrt, x);
+}
+
+double
+js::math_cbrt_uncached(double x)
+{
+    return cbrt(x);
+}
+
+bool
+js::math_cbrt(JSContext *cx, unsigned argc, Value *vp)
+{
+    return math_function<math_cbrt_impl>(cx, argc, vp);
+}
+
+#if JS_HAS_TOSOURCE
+static bool
+math_toSource(JSContext *cx, unsigned argc, Value *vp)
+{
+    CallArgs args = CallArgsFromVp(argc, vp);
+    args.rval().setString(cx->names().Math);
+    return true;
+}
+#endif
+
+static const JSFunctionSpec math_static_methods[] = {
+#if JS_HAS_TOSOURCE
+    JS_FN(js_toSource_str,  math_toSource,        0, 0),
+#endif
+    JS_FN("abs",            js_math_abs,          1, 0),
+    JS_FN("acos",           math_acos,            1, 0),
+    JS_FN("asin",           math_asin,            1, 0),
+    JS_FN("atan",           math_atan,            1, 0),
+    JS_FN("atan2",          math_atan2,           2, 0),
+    JS_FN("ceil",           math_ceil,            1, 0),
+    JS_FN("clz32",          math_clz32,           1, 0),
+    JS_FN("cos",            math_cos,             1, 0),
+    JS_FN("exp",            math_exp,             1, 0),
+    JS_FN("floor",          math_floor,           1, 0),
+    JS_FN("imul",           math_imul,            2, 0),
+    JS_FN("fround",         math_fround,          1, 0),
+    JS_FN("log",            math_log,             1, 0),
+    JS_FN("max",            js_math_max,          2, 0),
+    JS_FN("min",            js_math_min,          2, 0),
+    JS_FN("pow",            js_math_pow,          2, 0),
+    JS_FN("random",         js_math_random,       0, 0),
+    JS_FN("round",          math_round,           1, 0),
+    JS_FN("sin",            math_sin,             1, 0),
+    JS_FN("sqrt",           js_math_sqrt,         1, 0),
+    JS_FN("tan",            math_tan,             1, 0),
+    JS_FN("log10",          math_log10,           1, 0),
+    JS_FN("log2",           math_log2,            1, 0),
+    JS_FN("log1p",          math_log1p,           1, 0),
+    JS_FN("expm1",          math_expm1,           1, 0),
+    JS_FN("cosh",           math_cosh,            1, 0),
+    JS_FN("sinh",           math_sinh,            1, 0),
+    JS_FN("tanh",           math_tanh,            1, 0),
+    JS_FN("acosh",          math_acosh,           1, 0),
+    JS_FN("asinh",          math_asinh,           1, 0),
+    JS_FN("atanh",          math_atanh,           1, 0),
+    JS_FN("hypot",          math_hypot,           2, 0),
+    JS_FN("trunc",          math_trunc,           1, 0),
+    JS_FN("sign",           math_sign,            1, 0),
+    JS_FN("cbrt",           math_cbrt,            1, 0),
+    JS_FS_END
+};
+
+JSObject *
+js_InitMathClass(JSContext *cx, HandleObject obj)
+{
+    RootedObject proto(cx, obj->as<GlobalObject>().getOrCreateObjectPrototype(cx));
+    if (!proto)
+        return nullptr;
+    RootedObject Math(cx, NewObjectWithGivenProto(cx, &MathClass, proto, obj, SingletonObject));
+    if (!Math)
+        return nullptr;
+
+    if (!JS_DefineProperty(cx, obj, js_Math_str, Math, 0,
+                           JS_PropertyStub, JS_StrictPropertyStub))
+    {
+        return nullptr;
+    }
+
+    if (!JS_DefineFunctions(cx, Math, math_static_methods))
+        return nullptr;
+    if (!JS_DefineConstDoubles(cx, Math, math_constants))
+        return nullptr;
+
+    obj->as<GlobalObject>().setConstructor(JSProto_Math, ObjectValue(*Math));
+
+    return Math;
+}