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/* s_copysignl.c -- long double version of s_copysign.c. * Conversion to long double by Ulrich Drepper, * Cygnus Support, drepper@cygnus.com. */ /* * ==================================================== * 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. * ==================================================== */ /* * copysignl(long double x, long double y) * copysignl(x,y) returns a value with the magnitude of x and * with the sign bit of y. */ #include <endian.h> #include <stdint.h> #if __FLOAT_WORD_ORDER == BIG_ENDIAN typedef union { long double value; struct { int sign_exponent:16; unsigned int empty:16; uint32_t msw; uint32_t lsw; } parts; } ieee_long_double_shape_type; #endif #if __FLOAT_WORD_ORDER == LITTLE_ENDIAN typedef union { long double value; struct { uint32_t lsw; uint32_t msw; int sign_exponent:16; unsigned int empty:16; } parts; } ieee_long_double_shape_type; #endif /* Get int from the exponent of a long double. */ #define GET_LDOUBLE_EXP(exp,d) \ do { \ ieee_long_double_shape_type ge_u; \ ge_u.value = (d); \ (exp) = ge_u.parts.sign_exponent; \ } while (0) /* Set exponent of a long double from an int. */ #define SET_LDOUBLE_EXP(d,exp) \ do { \ ieee_long_double_shape_type se_u; \ se_u.value = (d); \ se_u.parts.sign_exponent = (exp); \ (d) = se_u.value; \ } while (0) long double copysignl(long double x, long double y); libc_hidden_proto(copysignl); long double copysignl(long double x, long double y) { uint32_t es1,es2; GET_LDOUBLE_EXP(es1,x); GET_LDOUBLE_EXP(es2,y); SET_LDOUBLE_EXP(x,(es1&0x7fff)|(es2&0x8000)); return x; } libc_hidden_def(copysignl); |