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#include "quadmath-imp.h"
#include <math.h>
#include <float.h>
#if __has_include("../../libgcc/soft-fp/soft-fp.h") \
&& __has_include("../../libgcc/soft-fp/quad.h") \
&& defined(FE_TONEAREST) \
&& defined(FE_UPWARD) \
&& defined(FE_DOWNWARD) \
&& defined(FE_TOWARDZERO) \
&& defined(FE_INEXACT)
#define USE_SOFT_FP 1
#if defined(_ARCH_PPC) && !defined(__LONG_DOUBLE_IEEE128__)
#define TFtype __float128
#endif
#include "../../libgcc/soft-fp/soft-fp.h"
#include "../../libgcc/soft-fp/quad.h"
#endif
__float128
sqrtq (const __float128 x)
{
__float128 y;
int exp;
if (isnanq (x) || (isinfq (x) && x > 0))
return x;
if (x == 0)
return x;
if (x < 0)
{
/* Return NaN with invalid signal. */
return (x - x) / (x - x);
}
#if USE_SOFT_FP
FP_DECL_EX;
FP_DECL_Q (X);
FP_DECL_Q (Y);
FP_INIT_ROUNDMODE;
FP_UNPACK_Q (X, x);
FP_SQRT_Q (Y, X);
FP_PACK_Q (y, Y);
FP_HANDLE_EXCEPTIONS;
return y;
#else
if (x <= DBL_MAX && x >= DBL_MIN)
{
/* Use double result as starting point. */
y = sqrt ((double) x);
/* Two Newton iterations. */
y -= 0.5q * (y - x / y);
y -= 0.5q * (y - x / y);
return y;
}
#ifdef HAVE_SQRTL
{
long double xl = (long double) x;
if (xl <= LDBL_MAX && xl >= LDBL_MIN)
{
/* Use long double result as starting point. */
y = (__float128) sqrtl (xl);
/* One Newton iteration. */
y -= 0.5q * (y - x / y);
return y;
}
}
#endif
/* If we're outside of the range of C types, we have to compute
the initial guess the hard way. */
y = frexpq (x, &exp);
if (exp % 2)
y *= 2, exp--;
y = sqrt (y);
y = scalbnq (y, exp / 2);
/* Two Newton iterations. */
y -= 0.5q * (y - x / y);
y -= 0.5q * (y - x / y);
return y;
#endif
}
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