[builtins] [turbofan] Refactor Float64Pow to use single implementation

Remove platform-specific Float64Pow implementations and utils Pow in
favor of a base::ieee754::pow implementation.

This unifies the implementation of pow for the compiler, wasm, and
runtime.

Bug: v8:5848, v8:5086
Change-Id: I968a08cef6a6d49350aa79185b2c6fb856d15f23
Reviewed-on: https://chromium-review.googlesource.com/c/1403018
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Reviewed-by: Georg Neis <neis@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59229}
diff --git a/src/base/ieee754.cc b/src/base/ieee754.cc
index 5203643..9dcdc27 100644
--- a/src/base/ieee754.cc
+++ b/src/base/ieee754.cc
@@ -2648,6 +2648,320 @@
 }
 
 /*
+ * ES2019 Draft 2019-01-02 12.6.4
+ * Math.pow & Exponentiation Operator
+ *
+ * Return X raised to the Yth power
+ *
+ * Method:
+ *     Let x =  2   * (1+f)
+ *     1. Compute and return log2(x) in two pieces:
+ *        log2(x) = w1 + w2,
+ *        where w1 has 53-24 = 29 bit trailing zeros.
+ *     2. Perform y*log2(x) = n+y' by simulating muti-precision
+ *        arithmetic, where |y'|<=0.5.
+ *     3. Return x**y = 2**n*exp(y'*log2)
+ *
+ * Special cases:
+ *     1.  (anything) ** 0  is 1
+ *     2.  (anything) ** 1  is itself
+ *     3.  (anything) ** NAN is NAN
+ *     4.  NAN ** (anything except 0) is NAN
+ *     5.  +-(|x| > 1) **  +INF is +INF
+ *     6.  +-(|x| > 1) **  -INF is +0
+ *     7.  +-(|x| < 1) **  +INF is +0
+ *     8.  +-(|x| < 1) **  -INF is +INF
+ *     9.  +-1         ** +-INF is NAN
+ *     10. +0 ** (+anything except 0, NAN)               is +0
+ *     11. -0 ** (+anything except 0, NAN, odd integer)  is +0
+ *     12. +0 ** (-anything except 0, NAN)               is +INF
+ *     13. -0 ** (-anything except 0, NAN, odd integer)  is +INF
+ *     14. -0 ** (odd integer) = -( +0 ** (odd integer) )
+ *     15. +INF ** (+anything except 0,NAN) is +INF
+ *     16. +INF ** (-anything except 0,NAN) is +0
+ *     17. -INF ** (anything)  = -0 ** (-anything)
+ *     18. (-anything) ** (integer) is (-1)**(integer)*(+anything**integer)
+ *     19. (-anything except 0 and inf) ** (non-integer) is NAN
+ *
+ * Accuracy:
+ *      pow(x,y) returns x**y nearly rounded. In particular,
+ *      pow(integer, integer) always returns the correct integer provided it is
+ *      representable.
+ *
+ * Constants:
+ *     The hexadecimal values are the intended ones for the following
+ *     constants. The decimal values may be used, provided that the
+ *     compiler will convert from decimal to binary accurately enough
+ *     to produce the hexadecimal values shown.
+ */
+
+#ifdef V8_TARGET_LITTLE_ENDIAN
+#define __HI(x) *(1 + reinterpret_cast<int*>(&x))
+#define __LO(x) *reinterpret_cast<int*>(&x)
+#else
+#define __HI(x) *reinterpret_cast<int*>(&x)
+#define __LO(x) *(1 + reinterpret_cast<int*>(&x))
+#endif
+
+double pow(double x, double y) {
+  static const double
+      bp[] = {1.0, 1.5},
+      dp_h[] = {0.0, 5.84962487220764160156e-01},  // 0x3FE2B803, 0x40000000
+      dp_l[] = {0.0, 1.35003920212974897128e-08},  // 0x3E4CFDEB, 0x43CFD006
+      zero = 0.0, one = 1.0, two = 2.0,
+      two53 = 9007199254740992.0,  // 0x43400000, 0x00000000
+      huge = 1.0e300, tiny = 1.0e-300,
+      // poly coefs for (3/2)*(log(x)-2s-2/3*s**3
+      L1 = 5.99999999999994648725e-01,      // 0x3FE33333, 0x33333303
+      L2 = 4.28571428578550184252e-01,      // 0x3FDB6DB6, 0xDB6FABFF
+      L3 = 3.33333329818377432918e-01,      // 0x3FD55555, 0x518F264D
+      L4 = 2.72728123808534006489e-01,      // 0x3FD17460, 0xA91D4101
+      L5 = 2.30660745775561754067e-01,      // 0x3FCD864A, 0x93C9DB65
+      L6 = 2.06975017800338417784e-01,      // 0x3FCA7E28, 0x4A454EEF
+      P1 = 1.66666666666666019037e-01,      // 0x3FC55555, 0x5555553E
+      P2 = -2.77777777770155933842e-03,     // 0xBF66C16C, 0x16BEBD93
+      P3 = 6.61375632143793436117e-05,      // 0x3F11566A, 0xAF25DE2C
+      P4 = -1.65339022054652515390e-06,     // 0xBEBBBD41, 0xC5D26BF1
+      P5 = 4.13813679705723846039e-08,      // 0x3E663769, 0x72BEA4D0
+      lg2 = 6.93147180559945286227e-01,     // 0x3FE62E42, 0xFEFA39EF
+      lg2_h = 6.93147182464599609375e-01,   // 0x3FE62E43, 0x00000000
+      lg2_l = -1.90465429995776804525e-09,  // 0xBE205C61, 0x0CA86C39
+      ovt = 8.0085662595372944372e-0017,    // -(1024-log2(ovfl+.5ulp))
+      cp = 9.61796693925975554329e-01,      // 0x3FEEC709, 0xDC3A03FD =2/(3ln2)
+      cp_h = 9.61796700954437255859e-01,    // 0x3FEEC709, 0xE0000000 =(float)cp
+      cp_l = -7.02846165095275826516e-09,   // 0xBE3E2FE0, 0x145B01F5 =tail cp_h
+      ivln2 = 1.44269504088896338700e+00,   // 0x3FF71547, 0x652B82FE =1/ln2
+      ivln2_h =
+          1.44269502162933349609e+00,  // 0x3FF71547, 0x60000000 =24b 1/ln2
+      ivln2_l =
+          1.92596299112661746887e-08;  // 0x3E54AE0B, 0xF85DDF44 =1/ln2 tail
+
+  double z, ax, z_h, z_l, p_h, p_l;
+  double y1, t1, t2, r, s, t, u, v, w;
+  int i, j, k, yisint, n;
+  int hx, hy, ix, iy;
+  unsigned lx, ly;
+
+  hx = __HI(x);
+  lx = __LO(x);
+  hy = __HI(y);
+  ly = __LO(y);
+  ix = hx & 0x7fffffff;
+  iy = hy & 0x7fffffff;
+
+  /* y==zero: x**0 = 1 */
+  if ((iy | ly) == 0) return one;
+
+  /* +-NaN return x+y */
+  if (ix > 0x7ff00000 || ((ix == 0x7ff00000) && (lx != 0)) || iy > 0x7ff00000 ||
+      ((iy == 0x7ff00000) && (ly != 0)))
+    return x + y;
+
+  /* determine if y is an odd int when x < 0
+   * yisint = 0 ... y is not an integer
+   * yisint = 1 ... y is an odd int
+   * yisint = 2 ... y is an even int
+   */
+  yisint = 0;
+  if (hx < 0) {
+    if (iy >= 0x43400000) {
+      yisint = 2; /* even integer y */
+    } else if (iy >= 0x3ff00000) {
+      k = (iy >> 20) - 0x3ff; /* exponent */
+      if (k > 20) {
+        j = ly >> (52 - k);
+        if ((j << (52 - k)) == static_cast<int>(ly)) yisint = 2 - (j & 1);
+      } else if (ly == 0) {
+        j = iy >> (20 - k);
+        if ((j << (20 - k)) == iy) yisint = 2 - (j & 1);
+      }
+    }
+  }
+
+  /* special value of y */
+  if (ly == 0) {
+    if (iy == 0x7ff00000) { /* y is +-inf */
+      if (((ix - 0x3ff00000) | lx) == 0)
+        return y - y;            /* inf**+-1 is NaN */
+      else if (ix >= 0x3ff00000) /* (|x|>1)**+-inf = inf,0 */
+        return (hy >= 0) ? y : zero;
+      else /* (|x|<1)**-,+inf = inf,0 */
+        return (hy < 0) ? -y : zero;
+    }
+    if (iy == 0x3ff00000) { /* y is  +-1 */
+      if (hy < 0)
+        return one / x;
+      else
+        return x;
+    }
+    if (hy == 0x40000000) return x * x; /* y is  2 */
+    if (hy == 0x3fe00000) {             /* y is  0.5 */
+      if (hx >= 0)                      /* x >= +0 */
+        return sqrt(x);
+    }
+  }
+
+  ax = fabs(x);
+  /* special value of x */
+  if (lx == 0) {
+    if (ix == 0x7ff00000 || ix == 0 || ix == 0x3ff00000) {
+      z = ax;                  /*x is +-0,+-inf,+-1*/
+      if (hy < 0) z = one / z; /* z = (1/|x|) */
+      if (hx < 0) {
+        if (((ix - 0x3ff00000) | yisint) == 0) {
+          z = (z - z) / (z - z); /* (-1)**non-int is NaN */
+        } else if (yisint == 1) {
+          z = -z; /* (x<0)**odd = -(|x|**odd) */
+        }
+      }
+      return z;
+    }
+  }
+
+  n = (hx >> 31) + 1;
+
+  /* (x<0)**(non-int) is NaN */
+  if ((n | yisint) == 0) return (x - x) / (x - x);
+
+  s = one; /* s (sign of result -ve**odd) = -1 else = 1 */
+  if ((n | (yisint - 1)) == 0) s = -one; /* (-ve)**(odd int) */
+
+  /* |y| is huge */
+  if (iy > 0x41e00000) {   /* if |y| > 2**31 */
+    if (iy > 0x43f00000) { /* if |y| > 2**64, must o/uflow */
+      if (ix <= 0x3fefffff) return (hy < 0) ? huge * huge : tiny * tiny;
+      if (ix >= 0x3ff00000) return (hy > 0) ? huge * huge : tiny * tiny;
+    }
+    /* over/underflow if x is not close to one */
+    if (ix < 0x3fefffff) return (hy < 0) ? s * huge * huge : s * tiny * tiny;
+    if (ix > 0x3ff00000) return (hy > 0) ? s * huge * huge : s * tiny * tiny;
+    /* now |1-x| is tiny <= 2**-20, suffice to compute
+       log(x) by x-x^2/2+x^3/3-x^4/4 */
+    t = ax - one; /* t has 20 trailing zeros */
+    w = (t * t) * (0.5 - t * (0.3333333333333333333333 - t * 0.25));
+    u = ivln2_h * t; /* ivln2_h has 21 sig. bits */
+    v = t * ivln2_l - w * ivln2;
+    t1 = u + v;
+    __LO(t1) = 0;
+    t2 = v - (t1 - u);
+  } else {
+    double ss, s2, s_h, s_l, t_h, t_l;
+    n = 0;
+    /* take care subnormal number */
+    if (ix < 0x00100000) {
+      ax *= two53;
+      n -= 53;
+      ix = __HI(ax);
+    }
+    n += ((ix) >> 20) - 0x3ff;
+    j = ix & 0x000fffff;
+    /* determine interval */
+    ix = j | 0x3ff00000; /* normalize ix */
+    if (j <= 0x3988E) {
+      k = 0; /* |x|<sqrt(3/2) */
+    } else if (j < 0xBB67A) {
+      k = 1; /* |x|<sqrt(3)   */
+    } else {
+      k = 0;
+      n += 1;
+      ix -= 0x00100000;
+    }
+    __HI(ax) = ix;
+
+    /* compute ss = s_h+s_l = (x-1)/(x+1) or (x-1.5)/(x+1.5) */
+    u = ax - bp[k]; /* bp[0]=1.0, bp[1]=1.5 */
+    v = one / (ax + bp[k]);
+    ss = u * v;
+    s_h = ss;
+    __LO(s_h) = 0;
+    /* t_h=ax+bp[k] High */
+    t_h = zero;
+    __HI(t_h) = ((ix >> 1) | 0x20000000) + 0x00080000 + (k << 18);
+    t_l = ax - (t_h - bp[k]);
+    s_l = v * ((u - s_h * t_h) - s_h * t_l);
+    /* compute log(ax) */
+    s2 = ss * ss;
+    r = s2 * s2 *
+        (L1 + s2 * (L2 + s2 * (L3 + s2 * (L4 + s2 * (L5 + s2 * L6)))));
+    r += s_l * (s_h + ss);
+    s2 = s_h * s_h;
+    t_h = 3.0 + s2 + r;
+    __LO(t_h) = 0;
+    t_l = r - ((t_h - 3.0) - s2);
+    /* u+v = ss*(1+...) */
+    u = s_h * t_h;
+    v = s_l * t_h + t_l * ss;
+    /* 2/(3log2)*(ss+...) */
+    p_h = u + v;
+    __LO(p_h) = 0;
+    p_l = v - (p_h - u);
+    z_h = cp_h * p_h; /* cp_h+cp_l = 2/(3*log2) */
+    z_l = cp_l * p_h + p_l * cp + dp_l[k];
+    /* log2(ax) = (ss+..)*2/(3*log2) = n + dp_h + z_h + z_l */
+    t = static_cast<double>(n);
+    t1 = (((z_h + z_l) + dp_h[k]) + t);
+    __LO(t1) = 0;
+    t2 = z_l - (((t1 - t) - dp_h[k]) - z_h);
+  }
+
+  /* split up y into y1+y2 and compute (y1+y2)*(t1+t2) */
+  y1 = y;
+  __LO(y1) = 0;
+  p_l = (y - y1) * t1 + y * t2;
+  p_h = y1 * t1;
+  z = p_l + p_h;
+  j = __HI(z);
+  i = __LO(z);
+  if (j >= 0x40900000) {               /* z >= 1024 */
+    if (((j - 0x40900000) | i) != 0) { /* if z > 1024 */
+      return s * huge * huge;          /* overflow */
+    } else {
+      if (p_l + ovt > z - p_h) return s * huge * huge; /* overflow */
+    }
+  } else if ((j & 0x7fffffff) >= 0x4090cc00) { /* z <= -1075 */
+    if (((j - 0xc090cc00) | i) != 0) {         /* z < -1075 */
+      return s * tiny * tiny;                  /* underflow */
+    } else {
+      if (p_l <= z - p_h) return s * tiny * tiny; /* underflow */
+    }
+  }
+  /*
+   * compute 2**(p_h+p_l)
+   */
+  i = j & 0x7fffffff;
+  k = (i >> 20) - 0x3ff;
+  n = 0;
+  if (i > 0x3fe00000) { /* if |z| > 0.5, set n = [z+0.5] */
+    n = j + (0x00100000 >> (k + 1));
+    k = ((n & 0x7fffffff) >> 20) - 0x3ff; /* new k for n */
+    t = zero;
+    __HI(t) = (n & ~(0x000fffff >> k));
+    n = ((n & 0x000fffff) | 0x00100000) >> (20 - k);
+    if (j < 0) n = -n;
+    p_h -= t;
+  }
+  t = p_l + p_h;
+  __LO(t) = 0;
+  u = t * lg2_h;
+  v = (p_l - (t - p_h)) * lg2 + t * lg2_l;
+  z = u + v;
+  w = v - (z - u);
+  t = z * z;
+  t1 = z - t * (P1 + t * (P2 + t * (P3 + t * (P4 + t * P5))));
+  r = (z * t1) / (t1 - two) - (w + z * w);
+  z = one - (r - z);
+  j = __HI(z);
+  j += (n << 20);
+  if ((j >> 20) <= 0)
+    z = scalbn(z, n); /* subnormal output */
+  else
+    __HI(z) += (n << 20);
+  return s * z;
+}
+#undef __HI
+#undef __LO
+
+/*
  * ES6 draft 09-27-13, section 20.2.2.30.
  * Math.sinh
  * Method :
@@ -2758,6 +3072,16 @@
   return (jx >= 0) ? z : -z;
 }
 
+#undef EXTRACT_WORDS
+#undef EXTRACT_WORD64
+#undef GET_HIGH_WORD
+#undef GET_LOW_WORD
+#undef INSERT_WORDS
+#undef INSERT_WORD64
+#undef SET_HIGH_WORD
+#undef SET_LOW_WORD
+#undef STRICT_ASSIGN
+
 }  // namespace ieee754
 }  // namespace base
 }  // namespace v8
diff --git a/src/base/ieee754.h b/src/base/ieee754.h
index 72f3db1..f2b3a3e 100644
--- a/src/base/ieee754.h
+++ b/src/base/ieee754.h
@@ -60,6 +60,14 @@
 // Returns exp(x)-1, the exponential of |x| minus 1.
 V8_BASE_EXPORT double expm1(double x);
 
+// Returns |x| to the power of |y|.
+// The result of base ** exponent when base is 1 or -1 and exponent is
+// +Infinity or -Infinity differs from IEEE 754-2008. The first edition
+// of ECMAScript specified a result of NaN for this operation, whereas
+// later versions of IEEE 754-2008 specified 1. The historical ECMAScript
+// behaviour is preserved for compatibility reasons.
+V8_BASE_EXPORT double pow(double x, double y);
+
 // Returns the sine of |x|, where |x| is given in radians.
 V8_BASE_EXPORT double sin(double x);
 
diff --git a/src/builtins/arm/builtins-arm.cc b/src/builtins/arm/builtins-arm.cc
index 6fdd938..65366be 100644
--- a/src/builtins/arm/builtins-arm.cc
+++ b/src/builtins/arm/builtins-arm.cc
@@ -2707,80 +2707,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const LowDwVfpRegister double_base = d0;
-  const LowDwVfpRegister double_exponent = d1;
-  const LowDwVfpRegister double_result = d2;
-  const LowDwVfpRegister double_scratch = d3;
-  const SwVfpRegister single_scratch = s6;
-  // Avoid using Registers r0-r3 as they may be needed when calling to C if the
-  // ABI is softfloat.
-  const Register integer_exponent = r4;
-  const Register scratch = r5;
-
-  Label call_runtime, done, int_exponent;
-
-  // Detect integer exponents stored as double.
-  __ TryDoubleToInt32Exact(integer_exponent, double_exponent, double_scratch);
-  __ b(eq, &int_exponent);
-
-  __ push(lr);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(lr);
-  __ MovFromFloatResult(double_result);
-  __ b(&done);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-
-  __ vmov(double_scratch, double_base);  // Back up base.
-  __ vmov(double_result, Double(1.0), scratch);
-
-  // Get absolute value of exponent.
-  __ cmp(integer_exponent, Operand::Zero());
-  __ mov(scratch, integer_exponent);
-  __ rsb(scratch, integer_exponent, Operand::Zero(), LeaveCC, mi);
-
-  Label while_true;
-  __ bind(&while_true);
-  __ mov(scratch, Operand(scratch, LSR, 1), SetCC);
-  __ vmul(double_result, double_result, double_scratch, cs);
-  __ vmul(double_scratch, double_scratch, double_scratch, ne);
-  __ b(ne, &while_true);
-
-  __ cmp(integer_exponent, Operand::Zero());
-  __ b(ge, &done);
-  __ vmov(double_scratch, Double(1.0), scratch);
-  __ vdiv(double_result, double_scratch, double_result);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ VFPCompareAndSetFlags(double_result, 0.0);
-  __ b(ne, &done);
-  // double_exponent may not containe the exponent value if the input was a
-  // smi.  We set it with exponent value before bailing out.
-  __ vmov(single_scratch, integer_exponent);
-  __ vcvt_f64_s32(double_exponent, single_scratch);
-
-  // Returning or bailing out.
-  __ push(lr);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(lr);
-  __ MovFromFloatResult(double_result);
-
-  __ bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r0 : argc
diff --git a/src/builtins/arm64/builtins-arm64.cc b/src/builtins/arm64/builtins-arm64.cc
index 8fadff4..079a862 100644
--- a/src/builtins/arm64/builtins-arm64.cc
+++ b/src/builtins/arm64/builtins-arm64.cc
@@ -3232,98 +3232,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  Register exponent_integer = x12;
-  Register saved_lr = x19;
-  VRegister result_double = d0;
-  VRegister base_double = d0;
-  VRegister exponent_double = d1;
-  VRegister base_double_copy = d2;
-  VRegister scratch1_double = d6;
-  VRegister scratch0_double = d7;
-
-  // A fast-path for integer exponents.
-  Label exponent_is_integer;
-  // Allocate a heap number for the result, and return it.
-  Label done;
-
-  // Unpack the inputs.
-
-  // Handle double (heap number) exponents.
-  // Detect integer exponents stored as doubles and handle those in the
-  // integer fast-path.
-  __ TryRepresentDoubleAsInt64(exponent_integer, exponent_double,
-                               scratch0_double, &exponent_is_integer);
-
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ Mov(saved_lr, lr);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-    __ Mov(lr, saved_lr);
-    __ B(&done);
-  }
-
-  __ Bind(&exponent_is_integer);
-
-  // Find abs(exponent). For negative exponents, we can find the inverse later.
-  Register exponent_abs = x13;
-  __ Cmp(exponent_integer, 0);
-  __ Cneg(exponent_abs, exponent_integer, mi);
-
-  // Repeatedly multiply to calculate the power.
-  //  result = 1.0;
-  //  For each bit n (exponent_integer{n}) {
-  //    if (exponent_integer{n}) {
-  //      result *= base;
-  //    }
-  //    base *= base;
-  //    if (remaining bits in exponent_integer are all zero) {
-  //      break;
-  //    }
-  //  }
-  Label power_loop, power_loop_entry, power_loop_exit;
-  __ Fmov(scratch1_double, base_double);
-  __ Fmov(base_double_copy, base_double);
-  __ Fmov(result_double, 1.0);
-  __ B(&power_loop_entry);
-
-  __ Bind(&power_loop);
-  __ Fmul(scratch1_double, scratch1_double, scratch1_double);
-  __ Lsr(exponent_abs, exponent_abs, 1);
-  __ Cbz(exponent_abs, &power_loop_exit);
-
-  __ Bind(&power_loop_entry);
-  __ Tbz(exponent_abs, 0, &power_loop);
-  __ Fmul(result_double, result_double, scratch1_double);
-  __ B(&power_loop);
-
-  __ Bind(&power_loop_exit);
-
-  // If the exponent was positive, result_double holds the result.
-  __ Tbz(exponent_integer, kXSignBit, &done);
-
-  // The exponent was negative, so find the inverse.
-  __ Fmov(scratch0_double, 1.0);
-  __ Fdiv(result_double, scratch0_double, result_double);
-  // ECMA-262 only requires Math.pow to return an 'implementation-dependent
-  // approximation' of base^exponent. However, mjsunit/math-pow uses Math.pow
-  // to calculate the subnormal value 2^-1074. This method of calculating
-  // negative powers doesn't work because 2^1074 overflows to infinity. To
-  // catch this corner-case, we bail out if the result was 0. (This can only
-  // occur if the divisor is infinity or the base is zero.)
-  __ Fcmp(result_double, 0.0);
-  __ B(&done, ne);
-
-  AllowExternalCallThatCantCauseGC scope(masm);
-  __ Mov(saved_lr, lr);
-  __ Fmov(base_double, base_double_copy);
-  __ Scvtf(exponent_double, exponent_integer);
-  __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  __ Mov(lr, saved_lr);
-  __ Bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- x0 : argc
diff --git a/src/builtins/builtins-definitions.h b/src/builtins/builtins-definitions.h
index 0a7c3c1..a4f870c 100644
--- a/src/builtins/builtins-definitions.h
+++ b/src/builtins/builtins-definitions.h
@@ -1344,7 +1344,6 @@
   TFC(GetProperty, GetProperty, 1)                                             \
   TFS(SetProperty, kReceiver, kKey, kValue)                                    \
   TFS(SetPropertyInLiteral, kReceiver, kKey, kValue)                           \
-  ASM(MathPowInternal, Dummy)                                                  \
   ASM(MemCopyUint8Uint8, CCall)                                                \
   ASM(MemCopyUint16Uint8, CCall)                                               \
   ASM(MemMove, CCall)                                                          \
diff --git a/src/builtins/ia32/builtins-ia32.cc b/src/builtins/ia32/builtins-ia32.cc
index 8e70a4c..faeb016 100644
--- a/src/builtins/ia32/builtins-ia32.cc
+++ b/src/builtins/ia32/builtins-ia32.cc
@@ -2886,137 +2886,6 @@
   __ ret(0);
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = eax;
-  const Register scratch = ecx;
-  const XMMRegister double_result = xmm3;
-  const XMMRegister double_base = xmm2;
-  const XMMRegister double_exponent = xmm1;
-  const XMMRegister double_scratch = xmm4;
-
-  Label call_runtime, done, exponent_not_smi, int_exponent;
-
-  // Save 1 in double_result - we need this several times later on.
-  __ mov(scratch, Immediate(1));
-  __ Cvtsi2sd(double_result, scratch);
-
-  Label fast_power, try_arithmetic_simplification;
-  __ DoubleToI(exponent, double_exponent, double_scratch,
-               &try_arithmetic_simplification, &try_arithmetic_simplification);
-  __ jmp(&int_exponent);
-
-  __ bind(&try_arithmetic_simplification);
-  // Skip to runtime if possibly NaN (indicated by the indefinite integer).
-  __ cvttsd2si(exponent, Operand(double_exponent));
-  __ cmp(exponent, Immediate(0x1));
-  __ j(overflow, &call_runtime);
-
-  // Using FPU instructions to calculate power.
-  Label fast_power_failed;
-  __ bind(&fast_power);
-  __ fnclex();  // Clear flags to catch exceptions later.
-  // Transfer (B)ase and (E)xponent onto the FPU register stack.
-  __ sub(esp, Immediate(kDoubleSize));
-  __ movsd(Operand(esp, 0), double_exponent);
-  __ fld_d(Operand(esp, 0));  // E
-  __ movsd(Operand(esp, 0), double_base);
-  __ fld_d(Operand(esp, 0));  // B, E
-
-  // Exponent is in st(1) and base is in st(0)
-  // B ^ E = (2^(E * log2(B)) - 1) + 1 = (2^X - 1) + 1 for X = E * log2(B)
-  // FYL2X calculates st(1) * log2(st(0))
-  __ fyl2x();    // X
-  __ fld(0);     // X, X
-  __ frndint();  // rnd(X), X
-  __ fsub(1);    // rnd(X), X-rnd(X)
-  __ fxch(1);    // X - rnd(X), rnd(X)
-  // F2XM1 calculates 2^st(0) - 1 for -1 < st(0) < 1
-  __ f2xm1();   // 2^(X-rnd(X)) - 1, rnd(X)
-  __ fld1();    // 1, 2^(X-rnd(X)) - 1, rnd(X)
-  __ faddp(1);  // 2^(X-rnd(X)), rnd(X)
-  // FSCALE calculates st(0) * 2^st(1)
-  __ fscale();  // 2^X, rnd(X)
-  __ fstp(1);   // 2^X
-  // Bail out to runtime in case of exceptions in the status word.
-  __ fnstsw_ax();
-  __ test_b(eax, Immediate(0x5F));  // We check for all but precision exception.
-  __ j(not_zero, &fast_power_failed, Label::kNear);
-  __ fstp_d(Operand(esp, 0));
-  __ movsd(double_result, Operand(esp, 0));
-  __ add(esp, Immediate(kDoubleSize));
-  __ jmp(&done);
-
-  __ bind(&fast_power_failed);
-  __ fninit();
-  __ add(esp, Immediate(kDoubleSize));
-  __ jmp(&call_runtime);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-  const XMMRegister double_scratch2 = double_exponent;
-  __ mov(scratch, exponent);                 // Back up exponent.
-  __ movsd(double_scratch, double_base);     // Back up base.
-  __ movsd(double_scratch2, double_result);  // Load double_exponent with 1.
-
-  // Get absolute value of exponent.
-  Label no_neg, while_true, while_false;
-  __ test(scratch, scratch);
-  __ j(positive, &no_neg, Label::kNear);
-  __ neg(scratch);
-  __ bind(&no_neg);
-
-  __ j(zero, &while_false, Label::kNear);
-  __ shr(scratch, 1);
-  // Above condition means CF==0 && ZF==0.  This means that the
-  // bit that has been shifted out is 0 and the result is not 0.
-  __ j(above, &while_true, Label::kNear);
-  __ movsd(double_result, double_scratch);
-  __ j(zero, &while_false, Label::kNear);
-
-  __ bind(&while_true);
-  __ shr(scratch, 1);
-  __ mulsd(double_scratch, double_scratch);
-  __ j(above, &while_true, Label::kNear);
-  __ mulsd(double_result, double_scratch);
-  __ j(not_zero, &while_true);
-
-  __ bind(&while_false);
-  // scratch has the original value of the exponent - if the exponent is
-  // negative, return 1/result.
-  __ test(exponent, exponent);
-  __ j(positive, &done);
-  __ divsd(double_scratch2, double_result);
-  __ movsd(double_result, double_scratch2);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ xorps(double_scratch2, double_scratch2);
-  __ ucomisd(double_scratch2, double_result);  // Result cannot be NaN.
-  // double_exponent aliased as double_scratch2 has already been overwritten
-  // and may not have contained the exponent value in the first place when the
-  // exponent is a smi.  We reset it with exponent value before bailing out.
-  __ j(not_equal, &done);
-  __ Cvtsi2sd(double_exponent, exponent);
-
-  // Returning or bailing out.
-  __ bind(&call_runtime);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(4, scratch);
-    __ movsd(Operand(esp, 0 * kDoubleSize), double_base);
-    __ movsd(Operand(esp, 1 * kDoubleSize), double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 4);
-  }
-  // Return value is in st(0) on ia32.
-  // Store it into the (fixed) result register.
-  __ sub(esp, Immediate(kDoubleSize));
-  __ fstp_d(Operand(esp, 0));
-  __ movsd(double_result, Operand(esp, 0));
-  __ add(esp, Immediate(kDoubleSize));
-
-  __ bind(&done);
-  __ ret(0);
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- eax : argc
diff --git a/src/builtins/mips/builtins-mips.cc b/src/builtins/mips/builtins-mips.cc
index 558e649..50e6d5e 100644
--- a/src/builtins/mips/builtins-mips.cc
+++ b/src/builtins/mips/builtins-mips.cc
@@ -2760,106 +2760,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = a2;
-  const DoubleRegister double_base = f2;
-  const DoubleRegister double_exponent = f4;
-  const DoubleRegister double_result = f0;
-  const DoubleRegister double_scratch = f6;
-  const FPURegister single_scratch = f8;
-  const Register scratch = t5;
-  const Register scratch2 = t3;
-
-  Label call_runtime, done, int_exponent;
-
-  Label int_exponent_convert;
-  // Detect integer exponents stored as double.
-  __ EmitFPUTruncate(kRoundToMinusInf, scratch, double_exponent, kScratchReg,
-                     double_scratch, scratch2, kCheckForInexactConversion);
-  // scratch2 == 0 means there was no conversion error.
-  __ Branch(&int_exponent_convert, eq, scratch2, Operand(zero_reg));
-
-  __ push(ra);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch2);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(ra);
-  __ MovFromFloatResult(double_result);
-  __ jmp(&done);
-
-  __ bind(&int_exponent_convert);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-
-  // Get two copies of exponent in the registers scratch and exponent.
-  // Exponent has previously been stored into scratch as untagged integer.
-  __ mov(exponent, scratch);
-
-  __ mov_d(double_scratch, double_base);  // Back up base.
-  __ Move(double_result, 1.0);
-
-  // Get absolute value of exponent.
-  Label positive_exponent, bail_out;
-  __ Branch(&positive_exponent, ge, scratch, Operand(zero_reg));
-  __ Subu(scratch, zero_reg, scratch);
-  // Check when Subu overflows and we get negative result
-  // (happens only when input is MIN_INT).
-  __ Branch(&bail_out, gt, zero_reg, Operand(scratch));
-  __ bind(&positive_exponent);
-  __ Assert(ge, AbortReason::kUnexpectedNegativeValue, scratch,
-            Operand(zero_reg));
-
-  Label while_true, no_carry, loop_end;
-  __ bind(&while_true);
-
-  __ And(scratch2, scratch, 1);
-
-  __ Branch(&no_carry, eq, scratch2, Operand(zero_reg));
-  __ mul_d(double_result, double_result, double_scratch);
-  __ bind(&no_carry);
-
-  __ sra(scratch, scratch, 1);
-
-  __ Branch(&loop_end, eq, scratch, Operand(zero_reg));
-  __ mul_d(double_scratch, double_scratch, double_scratch);
-
-  __ Branch(&while_true);
-
-  __ bind(&loop_end);
-
-  __ Branch(&done, ge, exponent, Operand(zero_reg));
-  __ Move(double_scratch, 1.0);
-  __ div_d(double_result, double_scratch, double_result);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ CompareF64(EQ, double_result, kDoubleRegZero);
-  __ BranchFalseShortF(&done);
-
-  // double_exponent may not contain the exponent value if the input was a
-  // smi.  We set it with exponent value before bailing out.
-  __ bind(&bail_out);
-  __ mtc1(exponent, single_scratch);
-  __ cvt_d_w(double_exponent, single_scratch);
-
-  // Returning or bailing out.
-  __ push(ra);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(ra);
-  __ MovFromFloatResult(double_result);
-
-  __ bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- a0 : argc
diff --git a/src/builtins/mips64/builtins-mips64.cc b/src/builtins/mips64/builtins-mips64.cc
index 6826fef..161433b 100644
--- a/src/builtins/mips64/builtins-mips64.cc
+++ b/src/builtins/mips64/builtins-mips64.cc
@@ -2797,106 +2797,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = a2;
-  const DoubleRegister double_base = f2;
-  const DoubleRegister double_exponent = f4;
-  const DoubleRegister double_result = f0;
-  const DoubleRegister double_scratch = f6;
-  const FPURegister single_scratch = f8;
-  const Register scratch = t1;
-  const Register scratch2 = a7;
-
-  Label call_runtime, done, int_exponent;
-
-  Label int_exponent_convert;
-  // Detect integer exponents stored as double.
-  __ EmitFPUTruncate(kRoundToMinusInf, scratch, double_exponent, kScratchReg,
-                     double_scratch, scratch2, kCheckForInexactConversion);
-  // scratch2 == 0 means there was no conversion error.
-  __ Branch(&int_exponent_convert, eq, scratch2, Operand(zero_reg));
-
-  __ push(ra);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch2);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(ra);
-  __ MovFromFloatResult(double_result);
-  __ jmp(&done);
-
-  __ bind(&int_exponent_convert);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-
-  // Get two copies of exponent in the registers scratch and exponent.
-  // Exponent has previously been stored into scratch as untagged integer.
-  __ mov(exponent, scratch);
-
-  __ mov_d(double_scratch, double_base);  // Back up base.
-  __ Move(double_result, 1.0);
-
-  // Get absolute value of exponent.
-  Label positive_exponent, bail_out;
-  __ Branch(&positive_exponent, ge, scratch, Operand(zero_reg));
-  __ Dsubu(scratch, zero_reg, scratch);
-  // Check when Dsubu overflows and we get negative result
-  // (happens only when input is MIN_INT).
-  __ Branch(&bail_out, gt, zero_reg, Operand(scratch));
-  __ bind(&positive_exponent);
-  __ Assert(ge, AbortReason::kUnexpectedNegativeValue, scratch,
-            Operand(zero_reg));
-
-  Label while_true, no_carry, loop_end;
-  __ bind(&while_true);
-
-  __ And(scratch2, scratch, 1);
-
-  __ Branch(&no_carry, eq, scratch2, Operand(zero_reg));
-  __ mul_d(double_result, double_result, double_scratch);
-  __ bind(&no_carry);
-
-  __ dsra(scratch, scratch, 1);
-
-  __ Branch(&loop_end, eq, scratch, Operand(zero_reg));
-  __ mul_d(double_scratch, double_scratch, double_scratch);
-
-  __ Branch(&while_true);
-
-  __ bind(&loop_end);
-
-  __ Branch(&done, ge, exponent, Operand(zero_reg));
-  __ Move(double_scratch, 1.0);
-  __ div_d(double_result, double_scratch, double_result);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ CompareF64(EQ, double_result, kDoubleRegZero);
-  __ BranchFalseShortF(&done);
-
-  // double_exponent may not contain the exponent value if the input was a
-  // smi.  We set it with exponent value before bailing out.
-  __ bind(&bail_out);
-  __ mtc1(exponent, single_scratch);
-  __ cvt_d_w(double_exponent, single_scratch);
-
-  // Returning or bailing out.
-  __ push(ra);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(ra);
-  __ MovFromFloatResult(double_result);
-
-  __ bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- a0 : argc
diff --git a/src/builtins/ppc/builtins-ppc.cc b/src/builtins/ppc/builtins-ppc.cc
index 47f6e79..fa40689 100644
--- a/src/builtins/ppc/builtins-ppc.cc
+++ b/src/builtins/ppc/builtins-ppc.cc
@@ -2836,100 +2836,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = r5;
-  const DoubleRegister double_base = d1;
-  const DoubleRegister double_exponent = d2;
-  const DoubleRegister double_result = d3;
-  const DoubleRegister double_scratch = d0;
-  const Register scratch = r11;
-  const Register scratch2 = r10;
-
-  Label call_runtime, done, int_exponent;
-
-  // Detect integer exponents stored as double.
-  __ TryDoubleToInt32Exact(scratch, double_exponent, scratch2, double_scratch);
-  __ beq(&int_exponent);
-
-  __ mflr(r0);
-  __ push(r0);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(r0);
-  __ mtlr(r0);
-  __ MovFromFloatResult(double_result);
-  __ b(&done);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-
-  // Get two copies of exponent in the registers scratch and exponent.
-  // Exponent has previously been stored into scratch as untagged integer.
-  __ mr(exponent, scratch);
-
-  __ fmr(double_scratch, double_base);  // Back up base.
-  __ li(scratch2, Operand(1));
-  __ ConvertIntToDouble(scratch2, double_result);
-
-  // Get absolute value of exponent.
-  __ cmpi(scratch, Operand::Zero());
-  if (CpuFeatures::IsSupported(ISELECT)) {
-    __ neg(scratch2, scratch);
-    __ isel(lt, scratch, scratch2, scratch);
-  } else {
-    Label positive_exponent;
-    __ bge(&positive_exponent);
-    __ neg(scratch, scratch);
-    __ bind(&positive_exponent);
-  }
-
-  Label while_true, no_carry, loop_end;
-  __ bind(&while_true);
-  __ andi(scratch2, scratch, Operand(1));
-  __ beq(&no_carry, cr0);
-  __ fmul(double_result, double_result, double_scratch);
-  __ bind(&no_carry);
-  __ ShiftRightImm(scratch, scratch, Operand(1), SetRC);
-  __ beq(&loop_end, cr0);
-  __ fmul(double_scratch, double_scratch, double_scratch);
-  __ b(&while_true);
-  __ bind(&loop_end);
-
-  __ cmpi(exponent, Operand::Zero());
-  __ bge(&done);
-
-  __ li(scratch2, Operand(1));
-  __ ConvertIntToDouble(scratch2, double_scratch);
-  __ fdiv(double_result, double_scratch, double_result);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ fcmpu(double_result, kDoubleRegZero);
-  __ bne(&done);
-  // double_exponent may not containe the exponent value if the input was a
-  // smi.  We set it with exponent value before bailing out.
-  __ ConvertIntToDouble(exponent, double_exponent);
-
-  // Returning or bailing out.
-  __ mflr(r0);
-  __ push(r0);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(r0);
-  __ mtlr(r0);
-  __ MovFromFloatResult(double_result);
-
-  __ bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r3 : argc
diff --git a/src/builtins/s390/builtins-s390.cc b/src/builtins/s390/builtins-s390.cc
index 2179e7b..022190c 100644
--- a/src/builtins/s390/builtins-s390.cc
+++ b/src/builtins/s390/builtins-s390.cc
@@ -2870,97 +2870,6 @@
   __ Ret();
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = r4;
-  const DoubleRegister double_base = d1;
-  const DoubleRegister double_exponent = d2;
-  const DoubleRegister double_result = d3;
-  const DoubleRegister double_scratch = d0;
-  const Register scratch = r1;
-  const Register scratch2 = r9;
-
-  Label call_runtime, done, int_exponent;
-
-  // Detect integer exponents stored as double.
-  __ TryDoubleToInt32Exact(scratch, double_exponent, scratch2, double_scratch);
-  __ beq(&int_exponent, Label::kNear);
-
-  __ push(r14);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(r14);
-  __ MovFromFloatResult(double_result);
-  __ b(&done);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-
-  // Get two copies of exponent in the registers scratch and exponent.
-  // Exponent has previously been stored into scratch as untagged integer.
-  __ LoadRR(exponent, scratch);
-
-  __ ldr(double_scratch, double_base);  // Back up base.
-  __ LoadImmP(scratch2, Operand(1));
-  __ ConvertIntToDouble(double_result, scratch2);
-
-  // Get absolute value of exponent.
-  Label positive_exponent;
-  __ CmpP(scratch, Operand::Zero());
-  __ bge(&positive_exponent, Label::kNear);
-  __ LoadComplementRR(scratch, scratch);
-  __ bind(&positive_exponent);
-
-  Label while_true, no_carry, loop_end;
-  __ bind(&while_true);
-  __ mov(scratch2, Operand(1));
-  __ AndP(scratch2, scratch);
-  __ beq(&no_carry, Label::kNear);
-  __ mdbr(double_result, double_scratch);
-  __ bind(&no_carry);
-  __ ShiftRightP(scratch, scratch, Operand(1));
-  __ LoadAndTestP(scratch, scratch);
-  __ beq(&loop_end, Label::kNear);
-  __ mdbr(double_scratch, double_scratch);
-  __ b(&while_true);
-  __ bind(&loop_end);
-
-  __ CmpP(exponent, Operand::Zero());
-  __ bge(&done);
-
-  // get 1/double_result:
-  __ ldr(double_scratch, double_result);
-  __ LoadImmP(scratch2, Operand(1));
-  __ ConvertIntToDouble(double_result, scratch2);
-  __ ddbr(double_result, double_scratch);
-
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ lzdr(kDoubleRegZero);
-  __ cdbr(double_result, kDoubleRegZero);
-  __ bne(&done, Label::kNear);
-  // double_exponent may not containe the exponent value if the input was a
-  // smi.  We set it with exponent value before bailing out.
-  __ ConvertIntToDouble(double_exponent, exponent);
-
-  // Returning or bailing out.
-  __ push(r14);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(0, 2, scratch);
-    __ MovToFloatParameters(double_base, double_exponent);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 0, 2);
-  }
-  __ pop(r14);
-  __ MovFromFloatResult(double_result);
-
-  __ bind(&done);
-  __ Ret();
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- r2 : argc
diff --git a/src/builtins/x64/builtins-x64.cc b/src/builtins/x64/builtins-x64.cc
index b6bce88..94aff64 100644
--- a/src/builtins/x64/builtins-x64.cc
+++ b/src/builtins/x64/builtins-x64.cc
@@ -2935,135 +2935,6 @@
   __ ret(0);
 }
 
-void Builtins::Generate_MathPowInternal(MacroAssembler* masm) {
-  const Register exponent = rdx;
-  const Register scratch = rcx;
-  const XMMRegister double_result = xmm3;
-  const XMMRegister double_base = xmm2;
-  const XMMRegister double_exponent = xmm1;
-  const XMMRegister double_scratch = xmm4;
-
-  Label call_runtime, done, exponent_not_smi, int_exponent;
-
-  // Save 1 in double_result - we need this several times later on.
-  __ movp(scratch, Immediate(1));
-  __ Cvtlsi2sd(double_result, scratch);
-
-  Label fast_power, try_arithmetic_simplification;
-  // Detect integer exponents stored as double.
-  __ DoubleToI(exponent, double_exponent, double_scratch,
-               &try_arithmetic_simplification, &try_arithmetic_simplification);
-  __ jmp(&int_exponent);
-
-  __ bind(&try_arithmetic_simplification);
-  __ Cvttsd2si(exponent, double_exponent);
-  // Skip to runtime if possibly NaN (indicated by the indefinite integer).
-  __ cmpl(exponent, Immediate(0x1));
-  __ j(overflow, &call_runtime);
-
-  // Using FPU instructions to calculate power.
-  Label fast_power_failed;
-  __ bind(&fast_power);
-  __ fnclex();  // Clear flags to catch exceptions later.
-  // Transfer (B)ase and (E)xponent onto the FPU register stack.
-  __ subq(rsp, Immediate(kDoubleSize));
-  __ Movsd(Operand(rsp, 0), double_exponent);
-  __ fld_d(Operand(rsp, 0));  // E
-  __ Movsd(Operand(rsp, 0), double_base);
-  __ fld_d(Operand(rsp, 0));  // B, E
-
-  // Exponent is in st(1) and base is in st(0)
-  // B ^ E = (2^(E * log2(B)) - 1) + 1 = (2^X - 1) + 1 for X = E * log2(B)
-  // FYL2X calculates st(1) * log2(st(0))
-  __ fyl2x();    // X
-  __ fld(0);     // X, X
-  __ frndint();  // rnd(X), X
-  __ fsub(1);    // rnd(X), X-rnd(X)
-  __ fxch(1);    // X - rnd(X), rnd(X)
-  // F2XM1 calculates 2^st(0) - 1 for -1 < st(0) < 1
-  __ f2xm1();   // 2^(X-rnd(X)) - 1, rnd(X)
-  __ fld1();    // 1, 2^(X-rnd(X)) - 1, rnd(X)
-  __ faddp(1);  // 2^(X-rnd(X)), rnd(X)
-  // FSCALE calculates st(0) * 2^st(1)
-  __ fscale();  // 2^X, rnd(X)
-  __ fstp(1);
-  // Bail out to runtime in case of exceptions in the status word.
-  __ fnstsw_ax();
-  __ testb(rax, Immediate(0x5F));  // Check for all but precision exception.
-  __ j(not_zero, &fast_power_failed, Label::kNear);
-  __ fstp_d(Operand(rsp, 0));
-  __ Movsd(double_result, Operand(rsp, 0));
-  __ addq(rsp, Immediate(kDoubleSize));
-  __ jmp(&done);
-
-  __ bind(&fast_power_failed);
-  __ fninit();
-  __ addq(rsp, Immediate(kDoubleSize));
-  __ jmp(&call_runtime);
-
-  // Calculate power with integer exponent.
-  __ bind(&int_exponent);
-  const XMMRegister double_scratch2 = double_exponent;
-  // Back up exponent as we need to check if exponent is negative later.
-  __ movp(scratch, exponent);                // Back up exponent.
-  __ Movsd(double_scratch, double_base);     // Back up base.
-  __ Movsd(double_scratch2, double_result);  // Load double_exponent with 1.
-
-  // Get absolute value of exponent.
-  Label no_neg, while_true, while_false;
-  __ testl(scratch, scratch);
-  __ j(positive, &no_neg, Label::kNear);
-  __ negl(scratch);
-  __ bind(&no_neg);
-
-  __ j(zero, &while_false, Label::kNear);
-  __ shrl(scratch, Immediate(1));
-  // Above condition means CF==0 && ZF==0.  This means that the
-  // bit that has been shifted out is 0 and the result is not 0.
-  __ j(above, &while_true, Label::kNear);
-  __ Movsd(double_result, double_scratch);
-  __ j(zero, &while_false, Label::kNear);
-
-  __ bind(&while_true);
-  __ shrl(scratch, Immediate(1));
-  __ Mulsd(double_scratch, double_scratch);
-  __ j(above, &while_true, Label::kNear);
-  __ Mulsd(double_result, double_scratch);
-  __ j(not_zero, &while_true);
-
-  __ bind(&while_false);
-  // If the exponent is negative, return 1/result.
-  __ testl(exponent, exponent);
-  __ j(greater, &done);
-  __ Divsd(double_scratch2, double_result);
-  __ Movsd(double_result, double_scratch2);
-  // Test whether result is zero.  Bail out to check for subnormal result.
-  // Due to subnormals, x^-y == (1/x)^y does not hold in all cases.
-  __ Xorpd(double_scratch2, double_scratch2);
-  __ Ucomisd(double_scratch2, double_result);
-  // double_exponent aliased as double_scratch2 has already been overwritten
-  // and may not have contained the exponent value in the first place when the
-  // input was a smi.  We reset it with exponent value before bailing out.
-  __ j(not_equal, &done);
-  __ Cvtlsi2sd(double_exponent, exponent);
-
-  // Returning or bailing out.
-  __ bind(&call_runtime);
-  // Move base to the correct argument register.  Exponent is already in xmm1.
-  __ Movsd(xmm0, double_base);
-  DCHECK(double_exponent == xmm1);
-  {
-    AllowExternalCallThatCantCauseGC scope(masm);
-    __ PrepareCallCFunction(2);
-    __ CallCFunction(ExternalReference::power_double_double_function(), 2);
-  }
-  // Return value is in xmm0.
-  __ Movsd(double_result, xmm0);
-
-  __ bind(&done);
-  __ ret(0);
-}
-
 void Builtins::Generate_InternalArrayConstructorImpl(MacroAssembler* masm) {
   // ----------- S t a t e -------------
   //  -- rax    : argc
diff --git a/src/compiler/backend/arm/code-generator-arm.cc b/src/compiler/backend/arm/code-generator-arm.cc
index 9d35305..8596005 100644
--- a/src/compiler/backend/arm/code-generator-arm.cc
+++ b/src/compiler/backend/arm/code-generator-arm.cc
@@ -1051,11 +1051,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
-      __ vmov(d0, d2);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/backend/arm64/code-generator-arm64.cc b/src/compiler/backend/arm64/code-generator-arm64.cc
index 58fed0b..6a12799 100644
--- a/src/compiler/backend/arm64/code-generator-arm64.cc
+++ b/src/compiler/backend/arm64/code-generator-arm64.cc
@@ -918,10 +918,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/backend/ia32/code-generator-ia32.cc b/src/compiler/backend/ia32/code-generator-ia32.cc
index 9dc6e50..463b7ec 100644
--- a/src/compiler/backend/ia32/code-generator-ia32.cc
+++ b/src/compiler/backend/ia32/code-generator-ia32.cc
@@ -982,20 +982,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      // TODO(bmeurer): Improve integration of the stub.
-      if (i.InputDoubleRegister(1) != xmm2) {
-        __ movaps(xmm2, i.InputDoubleRegister(0));
-        __ movaps(xmm1, i.InputDoubleRegister(1));
-      } else {
-        __ movaps(xmm0, i.InputDoubleRegister(0));
-        __ movaps(xmm1, xmm2);
-        __ movaps(xmm2, xmm0);
-      }
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
-      __ movaps(i.OutputDoubleRegister(), xmm3);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/backend/mips/code-generator-mips.cc b/src/compiler/backend/mips/code-generator-mips.cc
index af726bd..a18af56 100644
--- a/src/compiler/backend/mips/code-generator-mips.cc
+++ b/src/compiler/backend/mips/code-generator-mips.cc
@@ -970,10 +970,9 @@
     case kIeee754Float64Log2:
       ASSEMBLE_IEEE754_UNOP(log2);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/backend/mips64/code-generator-mips64.cc b/src/compiler/backend/mips64/code-generator-mips64.cc
index 8788fa7..95f4251 100644
--- a/src/compiler/backend/mips64/code-generator-mips64.cc
+++ b/src/compiler/backend/mips64/code-generator-mips64.cc
@@ -948,10 +948,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/backend/ppc/code-generator-ppc.cc b/src/compiler/backend/ppc/code-generator-ppc.cc
index b60fc9c..e90ac0a 100644
--- a/src/compiler/backend/ppc/code-generator-ppc.cc
+++ b/src/compiler/backend/ppc/code-generator-ppc.cc
@@ -1554,11 +1554,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
-      __ Move(d1, d3);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kPPC_Neg:
       __ neg(i.OutputRegister(), i.InputRegister(0), LeaveOE, i.OutputRCBit());
       break;
diff --git a/src/compiler/backend/s390/code-generator-s390.cc b/src/compiler/backend/s390/code-generator-s390.cc
index 757576d..9d2fd9f 100644
--- a/src/compiler/backend/s390/code-generator-s390.cc
+++ b/src/compiler/backend/s390/code-generator-s390.cc
@@ -2066,11 +2066,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
-      __ Move(d1, d3);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kS390_Neg32:
       __ lcr(i.OutputRegister(), i.InputRegister(0));
       CHECK_AND_ZERO_EXT_OUTPUT(1);
diff --git a/src/compiler/backend/x64/code-generator-x64.cc b/src/compiler/backend/x64/code-generator-x64.cc
index f766d56..7c41fbb 100644
--- a/src/compiler/backend/x64/code-generator-x64.cc
+++ b/src/compiler/backend/x64/code-generator-x64.cc
@@ -1084,13 +1084,9 @@
     case kIeee754Float64Log10:
       ASSEMBLE_IEEE754_UNOP(log10);
       break;
-    case kIeee754Float64Pow: {
-      // TODO(bmeurer): Improve integration of the stub.
-      __ Movsd(xmm2, xmm0);
-      __ Call(BUILTIN_CODE(isolate(), MathPowInternal), RelocInfo::CODE_TARGET);
-      __ Movsd(xmm0, xmm3);
+    case kIeee754Float64Pow:
+      ASSEMBLE_IEEE754_BINOP(pow);
       break;
-    }
     case kIeee754Float64Sin:
       ASSEMBLE_IEEE754_UNOP(sin);
       break;
diff --git a/src/compiler/machine-operator-reducer.cc b/src/compiler/machine-operator-reducer.cc
index e72a326..eb6db4e 100644
--- a/src/compiler/machine-operator-reducer.cc
+++ b/src/compiler/machine-operator-reducer.cc
@@ -563,7 +563,8 @@
     case IrOpcode::kFloat64Pow: {
       Float64BinopMatcher m(node);
       if (m.IsFoldable()) {
-        return ReplaceFloat64(Pow(m.left().Value(), m.right().Value()));
+        return ReplaceFloat64(
+            base::ieee754::pow(m.left().Value(), m.right().Value()));
       } else if (m.right().Is(0.0)) {  // x ** +-0.0 => 1.0
         return ReplaceFloat64(1.0);
       } else if (m.right().Is(-2.0)) {  // x ** -2.0 => 1 / (x * x)
diff --git a/src/debug/debug-evaluate.cc b/src/debug/debug-evaluate.cc
index a042764..2d533ca 100644
--- a/src/debug/debug-evaluate.cc
+++ b/src/debug/debug-evaluate.cc
@@ -949,7 +949,6 @@
     case Builtins::kFlattenIntoArray:
     case Builtins::kGetProperty:
     case Builtins::kHasProperty:
-    case Builtins::kMathPowInternal:
     case Builtins::kNonNumberToNumber:
     case Builtins::kNonPrimitiveToPrimitive_Number:
     case Builtins::kNumberToString:
diff --git a/src/external-reference.cc b/src/external-reference.cc
index becbfe6..14e7636 100644
--- a/src/external-reference.cc
+++ b/src/external-reference.cc
@@ -567,6 +567,8 @@
                              BUILTIN_FP_CALL)
 FUNCTION_REFERENCE_WITH_TYPE(ieee754_tanh_function, base::ieee754::tanh,
                              BUILTIN_FP_CALL)
+FUNCTION_REFERENCE_WITH_TYPE(ieee754_pow_function, base::ieee754::pow,
+                             BUILTIN_FP_FP_CALL)
 
 void* libc_memchr(void* string, int character, size_t search_length) {
   return memchr(string, character, search_length);
@@ -758,19 +760,8 @@
 FUNCTION_REFERENCE(invalidate_prototype_chains_function,
                    InvalidatePrototypeChainsWrapper)
 
-double power_double_double(double x, double y) {
-  // The checks for special cases can be dropped in ia32 because it has already
-  // been done in generated code before bailing out here.
-  if (std::isnan(y) || ((x == 1 || x == -1) && std::isinf(y))) {
-    return std::numeric_limits<double>::quiet_NaN();
-  }
-  return Pow(x, y);
-}
-
 double modulo_double_double(double x, double y) { return Modulo(x, y); }
 
-FUNCTION_REFERENCE_WITH_TYPE(power_double_double_function, power_double_double,
-                             BUILTIN_FP_FP_CALL)
 FUNCTION_REFERENCE_WITH_TYPE(mod_two_doubles_operation, modulo_double_double,
                              BUILTIN_FP_FP_CALL)
 
diff --git a/src/external-reference.h b/src/external-reference.h
index 59b2a87..aa143ed 100644
--- a/src/external-reference.h
+++ b/src/external-reference.h
@@ -129,6 +129,7 @@
   V(ieee754_log10_function, "base::ieee754::log10")                           \
   V(ieee754_log1p_function, "base::ieee754::log1p")                           \
   V(ieee754_log2_function, "base::ieee754::log2")                             \
+  V(ieee754_pow_function, "base::ieee754::pow")                               \
   V(ieee754_sin_function, "base::ieee754::sin")                               \
   V(ieee754_sinh_function, "base::ieee754::sinh")                             \
   V(ieee754_tan_function, "base::ieee754::tan")                               \
@@ -151,7 +152,6 @@
   V(mod_two_doubles_operation, "mod_two_doubles")                             \
   V(new_deoptimizer_function, "Deoptimizer::New()")                           \
   V(orderedhashmap_gethash_raw, "orderedhashmap_gethash_raw")                 \
-  V(power_double_double_function, "power_double_double_function")             \
   V(printf_function, "printf")                                                \
   V(refill_math_random, "MathRandom::RefillCache")                            \
   V(search_string_raw_one_one, "search_string_raw_one_one")                   \
@@ -325,9 +325,6 @@
 
 void abort_with_reason(int reason);
 
-// Computes pow(x, y) with the special cases in the spec for Math.pow.
-double power_double_double(double x, double y);
-
 }  // namespace internal
 }  // namespace v8
 
diff --git a/src/parsing/parser.cc b/src/parsing/parser.cc
index fffc331..659d882 100644
--- a/src/parsing/parser.cc
+++ b/src/parsing/parser.cc
@@ -12,6 +12,7 @@
 #include "src/ast/ast.h"
 #include "src/ast/source-range-ast-visitor.h"
 #include "src/bailout-reason.h"
+#include "src/base/ieee754.h"
 #include "src/base/overflowing-math.h"
 #include "src/base/platform/platform.h"
 #include "src/char-predicates-inl.h"
@@ -196,10 +197,9 @@
         *x = factory()->NewNumberLiteral(value, pos);
         return true;
       }
-      case Token::EXP: {
-        *x = factory()->NewNumberLiteral(Pow(x_val, y_val), pos);
+      case Token::EXP:
+        *x = factory()->NewNumberLiteral(base::ieee754::pow(x_val, y_val), pos);
         return true;
-      }
       default:
         break;
     }
diff --git a/src/utils.h b/src/utils.h
index 5161c10..01a8fc7 100644
--- a/src/utils.h
+++ b/src/utils.h
@@ -253,35 +253,6 @@
 #endif
 }
 
-inline double Pow(double x, double y) {
-  if (y == 0.0) return 1.0;
-  if (std::isnan(y) || ((x == 1 || x == -1) && std::isinf(y))) {
-    return std::numeric_limits<double>::quiet_NaN();
-  }
-#if (defined(__MINGW64_VERSION_MAJOR) &&                              \
-     (!defined(__MINGW64_VERSION_RC) || __MINGW64_VERSION_RC < 1)) || \
-    defined(V8_OS_AIX)
-  // MinGW64 and AIX have a custom implementation for pow.  This handles certain
-  // special cases that are different.
-  if ((x == 0.0 || std::isinf(x)) && y != 0.0 && std::isfinite(y)) {
-    double f;
-    double result = ((x == 0.0) ^ (y > 0)) ? V8_INFINITY : 0;
-    /* retain sign if odd integer exponent */
-    return ((std::modf(y, &f) == 0.0) && (static_cast<int64_t>(y) & 1))
-               ? copysign(result, x)
-               : result;
-  }
-
-  if (x == 2.0) {
-    int y_int = static_cast<int>(y);
-    if (y == y_int) {
-      return std::ldexp(1.0, y_int);
-    }
-  }
-#endif
-  return std::pow(x, y);
-}
-
 template <typename T>
 T SaturateAdd(T a, T b) {
   if (std::is_signed<T>::value) {
diff --git a/src/wasm/wasm-external-refs.cc b/src/wasm/wasm-external-refs.cc
index 9fc3b70..0dcd3ed 100644
--- a/src/wasm/wasm-external-refs.cc
+++ b/src/wasm/wasm-external-refs.cc
@@ -10,6 +10,7 @@
 #include "include/v8config.h"
 
 #include "src/base/bits.h"
+#include "src/base/ieee754.h"
 #include "src/memcopy.h"
 #include "src/utils.h"
 #include "src/v8memory.h"
@@ -245,7 +246,7 @@
 void float64_pow_wrapper(Address data) {
   double x = ReadUnalignedValue<double>(data);
   double y = ReadUnalignedValue<double>(data + sizeof(x));
-  WriteUnalignedValue<double>(data, Pow(x, y));
+  WriteUnalignedValue<double>(data, base::ieee754::pow(x, y));
 }
 
 void memory_copy_wrapper(Address dst, Address src, uint32_t size) {
diff --git a/test/mjsunit/regress/regress-v8-5848.js b/test/mjsunit/regress/regress-v8-5848.js
new file mode 100644
index 0000000..9db3666
--- /dev/null
+++ b/test/mjsunit/regress/regress-v8-5848.js
@@ -0,0 +1,17 @@
+// Copyright 2018 the V8 project authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+const inlineFromParser = 50 ** 50;
+
+const i = 50;
+const fromRuntimePowOp = i ** i;
+const fromRuntimeMath = Math.pow(i, i);
+
+// inlineFromParser === fromRuntimeOp === fromRuntimeMath
+
+assertEquals(inlineFromParser, fromRuntimePowOp);
+assertEquals(inlineFromParser - fromRuntimePowOp, 0);
+
+assertEquals(inlineFromParser, fromRuntimeMath);
+assertEquals(inlineFromParser - fromRuntimeMath, 0);
diff --git a/test/unittests/compiler/machine-operator-reducer-unittest.cc b/test/unittests/compiler/machine-operator-reducer-unittest.cc
index 2a67042..7782636 100644
--- a/test/unittests/compiler/machine-operator-reducer-unittest.cc
+++ b/test/unittests/compiler/machine-operator-reducer-unittest.cc
@@ -1959,8 +1959,9 @@
       Reduction const r = Reduce(graph()->NewNode(
           machine()->Float64Pow(), Float64Constant(x), Float64Constant(y)));
       ASSERT_TRUE(r.Changed());
-      EXPECT_THAT(r.replacement(),
-                  IsFloat64Constant(NanSensitiveDoubleEq(Pow(x, y))));
+      EXPECT_THAT(
+          r.replacement(),
+          IsFloat64Constant(NanSensitiveDoubleEq(base::ieee754::pow(x, y))));
     }
   }
 }