newlib-cygwin/newlib/libm/machine/amdgcn/v64sf_scalbn.c

93 lines
3.0 KiB
C

/*
* Copyright 2023 Siemens
*
* The authors hereby grant permission to use, copy, modify, distribute,
* and license this software and its documentation for any purpose, provided
* that existing copyright notices are retained in all copies and that this
* notice is included verbatim in any distributions. No written agreement,
* license, or royalty fee is required for any of the authorized uses.
* Modifications to this software may be copyrighted by their authors
* and need not follow the licensing terms described here, provided that
* the new terms are clearly indicated on the first page of each file where
* they apply.
*/
/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/* Based on newlib/libm/common/sf_scalbn.c in Newlib. */
#include "amdgcnmach.h"
#include <limits.h>
#include <float.h>
#if INT_MAX > 50000
#define OVERFLOW_INT 50000
#else
#define OVERFLOW_INT 30000
#endif
static const float
two25 = 3.355443200e+07, /* 0x4c000000 */
twom25 = 2.9802322388e-08, /* 0x33000000 */
huge = 1.0e+30,
tiny = 1.0e-30;
v64sf v64sf_copysignf_aux (v64sf, v64sf, v64si);
DEF_VS_MATH_FUNC (v64sf, scalbnf, v64sf x, v64si n)
{
FUNCTION_INIT (v64sf);
const v64sf huge_v = VECTOR_INIT ((float) huge);
const v64sf tiny_v = VECTOR_INIT ((float) tiny);
v64si ix;
GET_FLOAT_WORD (ix, x, NO_COND);
v64si hx = ix & 0x7fffffff;
v64si k = hx >> 23; /* extract exponent */
VECTOR_IF (FLT_UWORD_IS_ZERO(hx), cond)
VECTOR_RETURN (x, cond);
VECTOR_ENDIF
VECTOR_IF (~FLT_UWORD_IS_FINITE(hx), cond) /* NaN or Inf */
VECTOR_RETURN (x + x, cond);
VECTOR_ENDIF
VECTOR_IF (FLT_UWORD_IS_SUBNORMAL (hx), cond);
VECTOR_COND_MOVE (x, x * two25, cond);
GET_FLOAT_WORD (ix, x, cond);
VECTOR_COND_MOVE (k, ((ix & 0x7f800000) >> 23) - 25, cond);
VECTOR_IF2 (n < -50000, cond2, cond) /*underflow*/
VECTOR_RETURN (tiny * x, cond2);
VECTOR_ENDIF
VECTOR_ENDIF
VECTOR_IF (n > OVERFLOW_INT, cond) // in case integer overflow in n+k
VECTOR_RETURN (huge_v * v64sf_copysignf_aux (huge_v, x, __mask), cond);
VECTOR_ENDIF
k = k + n;
VECTOR_IF (k > FLT_LARGEST_EXP, cond) /* overflow */
VECTOR_RETURN (huge_v * v64sf_copysignf_aux (huge_v, x, __mask), cond);
VECTOR_ENDIF
VECTOR_IF (k > 0, cond) /* normal result */
SET_FLOAT_WORD (x, (ix & 0x807fffff) | (k << 23), cond);
VECTOR_RETURN (x, cond);
VECTOR_ENDIF
VECTOR_IF (k < FLT_SMALLEST_EXP, cond) /*underflow*/
VECTOR_RETURN (tiny_v * v64sf_copysignf_aux (tiny_v, x, __mask),
k < FLT_SMALLEST_EXP);
VECTOR_ENDIF
k += 25; /* subnormal result */
SET_FLOAT_WORD (x, (ix & 0x807fffff) | (k << 23), NO_COND);
VECTOR_RETURN (x * twom25, NO_COND);
FUNCTION_RETURN;
}