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* sysdeps/sparc/jmp_buf.h: Rewritten; use array of ints, not struct. * sysdeps/sparc/setjmp.S: Rewritten; store %fp value as well. * sysdeps/sparc/__longjmp.S: Rewritten; unwind frames one by one with `restore' until the target frame is hit. Sun Mar 10 20:29:40 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * sysdeps/unix/sysv/linux/sigsuspend.c: New file. * sysdeps/unix/sysv/linux/syscalls.list: Remove sigsuspend, add s_sigsuspend. Thu Mar 7 21:30:58 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de> * Makerules (+make-deps, sed-remove-objpfx): Quote periods on the left side of sed substitutions. Sun Mar 10 16:58:10 1996 Ulrich Drepper <drepper@gnu.ai.mit.edu> * stdio-common/printf_fp.c (hack_digit): __mpn_normal_size is not available anymore. Do it ourselves. * sysdeps/unix/sysv/linux/i386/fpu_control.h (_FPU_SETCW): Correct GCC `asm' syntax. * stdio-common/Makefile (tests): Add tst-ungetc. * stdio-common/tst-ungetc.c: New test from drepper. * stdio-common/tstscanf.c (main): New %[ test case from drepper. * sysdeps/libm-ieee754/s_scalbn.c (scalbn): Rename to __scalbn; somehow this was missed, though the weak alias is already there.
68 lines
2.0 KiB
C
68 lines
2.0 KiB
C
/* @(#)s_scalbn.c 5.1 93/09/24 */
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/*
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* ====================================================
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* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
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*
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* Developed at SunPro, a Sun Microsystems, Inc. business.
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* Permission to use, copy, modify, and distribute this
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* software is freely granted, provided that this notice
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* is preserved.
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* ====================================================
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*/
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#if defined(LIBM_SCCS) && !defined(lint)
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static char rcsid[] = "$NetBSD: s_scalbn.c,v 1.8 1995/05/10 20:48:08 jtc Exp $";
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#endif
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/*
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* scalbn (double x, int n)
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* scalbn(x,n) returns x* 2**n computed by exponent
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* manipulation rather than by actually performing an
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* exponentiation or a multiplication.
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*/
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#include "math.h"
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#include "math_private.h"
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#ifdef __STDC__
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static const double
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#else
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static double
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#endif
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two54 = 1.80143985094819840000e+16, /* 0x43500000, 0x00000000 */
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twom54 = 5.55111512312578270212e-17, /* 0x3C900000, 0x00000000 */
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huge = 1.0e+300,
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tiny = 1.0e-300;
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#ifdef __STDC__
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double __scalbn (double x, int n)
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#else
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double __scalbn (x,n)
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double x; int n;
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#endif
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{
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int32_t k,hx,lx;
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EXTRACT_WORDS(hx,lx,x);
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k = (hx&0x7ff00000)>>20; /* extract exponent */
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if (k==0) { /* 0 or subnormal x */
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if ((lx|(hx&0x7fffffff))==0) return x; /* +-0 */
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x *= two54;
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GET_HIGH_WORD(hx,x);
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k = ((hx&0x7ff00000)>>20) - 54;
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if (n< -50000) return tiny*x; /*underflow*/
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}
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if (k==0x7ff) return x+x; /* NaN or Inf */
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k = k+n;
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if (k > 0x7fe) return huge*__copysign(huge,x); /* overflow */
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if (k > 0) /* normal result */
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{SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20)); return x;}
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if (k <= -54)
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if (n > 50000) /* in case integer overflow in n+k */
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return huge*__copysign(huge,x); /*overflow*/
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else return tiny*__copysign(tiny,x); /*underflow*/
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k += 54; /* subnormal result */
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SET_HIGH_WORD(x,(hx&0x800fffff)|(k<<20));
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return x*twom54;
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}
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weak_alias (__scalbn, scalbn)
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