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+/* ieee.c
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+ *
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+ * Extended precision IEEE binary floating point arithmetic routines
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+ *
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+ * Numbers are stored in C language as arrays of 16-bit unsigned
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+ * short integers. The arguments of the routines are pointers to
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+ * the arrays.
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+ *
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+ *
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+ * External e type data structure, simulates Intel 8087 chip
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+ * temporary real format but possibly with a larger significand:
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+ *
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+ * NE-1 significand words (least significant word first,
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+ * most significant bit is normally set)
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+ * exponent (value = EXONE for 1.0,
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+ * top bit is the sign)
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+ *
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+ *
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+ * Internal data structure of a number (a "word" is 16 bits):
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+ *
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+ * ei[0] sign word (0 for positive, 0xffff for negative)
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+ * ei[1] biased exponent (value = EXONE for the number 1.0)
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+ * ei[2] high guard word (always zero after normalization)
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+ * ei[3]
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+ * to ei[NI-2] significand (NI-4 significand words,
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+ * most significant word first,
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+ * most significant bit is set)
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+ * ei[NI-1] low guard word (0x8000 bit is rounding place)
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+ *
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+ *
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+ *
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+ * Routines for external format numbers
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+ *
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+ * asctoe( string, e ) ASCII string to extended double e type
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+ * asctoe64( string, &d ) ASCII string to long double
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+ * asctoe53( string, &d ) ASCII string to double
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+ * asctoe24( string, &f ) ASCII string to single
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+ * asctoeg( string, e, prec ) ASCII string to specified precision
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+ * e24toe( &f, e ) IEEE single precision to e type
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+ * e53toe( &d, e ) IEEE double precision to e type
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+ * e64toe( &d, e ) IEEE long double precision to e type
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+ * eabs(e) absolute value
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+ * eadd( a, b, c ) c = b + a
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+ * eclear(e) e = 0
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+ * ecmp (a, b) Returns 1 if a > b, 0 if a == b,
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+ * -1 if a < b, -2 if either a or b is a NaN.
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+ * ediv( a, b, c ) c = b / a
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+ * efloor( a, b ) truncate to integer, toward -infinity
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+ * efrexp( a, exp, s ) extract exponent and significand
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+ * eifrac( e, &l, frac ) e to long integer and e type fraction
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+ * euifrac( e, &l, frac ) e to unsigned long integer and e type fraction
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+ * einfin( e ) set e to infinity, leaving its sign alone
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+ * eldexp( a, n, b ) multiply by 2**n
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+ * emov( a, b ) b = a
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+ * emul( a, b, c ) c = b * a
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+ * eneg(e) e = -e
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+ * eround( a, b ) b = nearest integer value to a
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+ * esub( a, b, c ) c = b - a
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+ * e24toasc( &f, str, n ) single to ASCII string, n digits after decimal
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+ * e53toasc( &d, str, n ) double to ASCII string, n digits after decimal
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+ * e64toasc( &d, str, n ) long double to ASCII string
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+ * etoasc( e, str, n ) e to ASCII string, n digits after decimal
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+ * etoe24( e, &f ) convert e type to IEEE single precision
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+ * etoe53( e, &d ) convert e type to IEEE double precision
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+ * etoe64( e, &d ) convert e type to IEEE long double precision
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+ * ltoe( &l, e ) long (32 bit) integer to e type
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+ * ultoe( &l, e ) unsigned long (32 bit) integer to e type
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+ * eisneg( e ) 1 if sign bit of e != 0, else 0
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+ * eisinf( e ) 1 if e has maximum exponent (non-IEEE)
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+ * or is infinite (IEEE)
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+ * eisnan( e ) 1 if e is a NaN
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+ * esqrt( a, b ) b = square root of a
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+ *
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+ *
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+ * Routines for internal format numbers
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+ *
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+ * eaddm( ai, bi ) add significands, bi = bi + ai
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+ * ecleaz(ei) ei = 0
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+ * ecleazs(ei) set ei = 0 but leave its sign alone
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+ * ecmpm( ai, bi ) compare significands, return 1, 0, or -1
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+ * edivm( ai, bi ) divide significands, bi = bi / ai
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+ * emdnorm(ai,l,s,exp) normalize and round off
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+ * emovi( a, ai ) convert external a to internal ai
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+ * emovo( ai, a ) convert internal ai to external a
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+ * emovz( ai, bi ) bi = ai, low guard word of bi = 0
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+ * emulm( ai, bi ) multiply significands, bi = bi * ai
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+ * enormlz(ei) left-justify the significand
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+ * eshdn1( ai ) shift significand and guards down 1 bit
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+ * eshdn8( ai ) shift down 8 bits
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+ * eshdn6( ai ) shift down 16 bits
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+ * eshift( ai, n ) shift ai n bits up (or down if n < 0)
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+ * eshup1( ai ) shift significand and guards up 1 bit
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+ * eshup8( ai ) shift up 8 bits
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+ * eshup6( ai ) shift up 16 bits
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+ * esubm( ai, bi ) subtract significands, bi = bi - ai
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+ *
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+ *
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+ * The result is always normalized and rounded to NI-4 word precision
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+ * after each arithmetic operation.
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+ *
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+ * Exception flags are NOT fully supported.
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+ *
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+ * Define INFINITY in mconf.h for support of infinity; otherwise a
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+ * saturation arithmetic is implemented.
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+ *
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+ * Define NANS for support of Not-a-Number items; otherwise the
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+ * arithmetic will never produce a NaN output, and might be confused
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+ * by a NaN input.
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+ * If NaN's are supported, the output of ecmp(a,b) is -2 if
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+ * either a or b is a NaN. This means asking if(ecmp(a,b) < 0)
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+ * may not be legitimate. Use if(ecmp(a,b) == -1) for less-than
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+ * if in doubt.
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+ * Signaling NaN's are NOT supported; they are treated the same
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+ * as quiet NaN's.
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+ *
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+ * Denormals are always supported here where appropriate (e.g., not
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+ * for conversion to DEC numbers).
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+ */
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+
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+/*
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+ * Revision history:
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+ *
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+ * 5 Jan 84 PDP-11 assembly language version
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+ * 2 Mar 86 fixed bug in asctoq()
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+ * 6 Dec 86 C language version
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+ * 30 Aug 88 100 digit version, improved rounding
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+ * 15 May 92 80-bit long double support
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+ *
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+ * Author: S. L. Moshier.
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+ */
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+
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+#include <stdio.h>
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+/* #include "\usr\include\stdio.h" */
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+#include "ehead.h"
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+#include "mconf.h"
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+
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+/* Change UNK into something else. */
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+#ifdef UNK
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+#undef UNK
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+#define IBMPC 1
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+#endif
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+
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+/* NaN's require infinity support. */
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+#ifdef NANS
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+#ifndef INFINITY
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+#define INFINITY
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+#endif
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+#endif
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+
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+/* This handles 64-bit long ints. */
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+#define LONGBITS (8 * sizeof(long))
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+
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+/* Control register for rounding precision.
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+ * This can be set to 80 (if NE=6), 64, 56, 53, or 24 bits.
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+ */
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+int rndprc = NBITS;
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+extern int rndprc;
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+
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+void eaddm(), esubm(), emdnorm(), asctoeg(), enan();
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+static void toe24(), toe53(), toe64(), toe113();
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+void eremain(), einit(), eiremain();
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+int ecmpm(), edivm(), emulm(), eisneg(), eisinf();
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+void emovi(), emovo(), emovz(), ecleaz(), eadd1();
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+void etodec(), todec(), dectoe();
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+int eisnan(), eiisnan();
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+
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+
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+
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+void einit()
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+{
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+}
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+
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+/*
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+; Clear out entire external format number.
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+;
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+; unsigned short x[];
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+; eclear( x );
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+*/
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+
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+void eclear( x )
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+register unsigned short *x;
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+{
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+register int i;
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+
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+for( i=0; i<NE; i++ )
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+ *x++ = 0;
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+}
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+
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+
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+
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+/* Move external format number from a to b.
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+ *
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+ * emov( a, b );
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+ */
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+
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+void emov( a, b )
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+register unsigned short *a, *b;
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+{
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+register int i;
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+
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+for( i=0; i<NE; i++ )
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+ *b++ = *a++;
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+}
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+
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+
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+/*
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+; Absolute value of external format number
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+;
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+; short x[NE];
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+; eabs( x );
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+*/
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+
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+void eabs(x)
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+unsigned short x[]; /* x is the memory address of a short */
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+{
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+
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+x[NE-1] &= 0x7fff; /* sign is top bit of last word of external format */
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+}
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+
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+
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+
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+
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+/*
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+; Negate external format number
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+;
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+; unsigned short x[NE];
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+; eneg( x );
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+*/
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+
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+void eneg(x)
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+unsigned short x[];
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+{
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+
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+#ifdef NANS
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+if( eisnan(x) )
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+ return;
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+#endif
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+x[NE-1] ^= 0x8000; /* Toggle the sign bit */
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+}
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+
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+
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+
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+/* Return 1 if external format number is negative,
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+ * else return zero.
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+ */
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+int eisneg(x)
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+unsigned short x[];
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+{
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+
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+#ifdef NANS
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+if( eisnan(x) )
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+ return( 0 );
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+#endif
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+if( x[NE-1] & 0x8000 )
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+ return( 1 );
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+else
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+ return( 0 );
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+}
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+
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+
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+/* Return 1 if external format number has maximum possible exponent,
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+ * else return zero.
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+ */
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+int eisinf(x)
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+unsigned short x[];
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+{
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+
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+if( (x[NE-1] & 0x7fff) == 0x7fff )
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+ {
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+#ifdef NANS
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+ if( eisnan(x) )
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+ return( 0 );
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+#endif
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+ return( 1 );
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+ }
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+else
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+ return( 0 );
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+}
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+
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+/* Check if e-type number is not a number.
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+ */
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+int eisnan(x)
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+unsigned short x[];
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+{
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+
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+#ifdef NANS
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+int i;
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+/* NaN has maximum exponent */
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+if( (x[NE-1] & 0x7fff) != 0x7fff )
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+ return (0);
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+/* ... and non-zero significand field. */
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+for( i=0; i<NE-1; i++ )
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+ {
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+ if( *x++ != 0 )
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+ return (1);
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+ }
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+#endif
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+return (0);
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+}
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+
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+/*
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+; Fill entire number, including exponent and significand, with
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+; largest possible number. These programs implement a saturation
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+; value that is an ordinary, legal number. A special value
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+; "infinity" may also be implemented; this would require tests
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+; for that value and implementation of special rules for arithmetic
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+; operations involving inifinity.
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+*/
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+
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+void einfin(x)
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+register unsigned short *x;
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+{
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+register int i;
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+
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+#ifdef INFINITY
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+for( i=0; i<NE-1; i++ )
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+ *x++ = 0;
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+*x |= 32767;
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+#else
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+for( i=0; i<NE-1; i++ )
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+ *x++ = 0xffff;
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+*x |= 32766;
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+if( rndprc < NBITS )
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+ {
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+ if (rndprc == 113)
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+ {
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+ *(x - 9) = 0;
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+ *(x - 8) = 0;
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+ }
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+ if( rndprc == 64 )
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+ {
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+ *(x-5) = 0;
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+ }
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+ if( rndprc == 53 )
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+ {
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+ *(x-4) = 0xf800;
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+ }
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+ else
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+ {
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+ *(x-4) = 0;
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+ *(x-3) = 0;
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+ *(x-2) = 0xff00;
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+ }
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+ }
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+#endif
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+}
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+
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+
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+
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+/* Move in external format number,
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+ * converting it to internal format.
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+ */
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+void emovi( a, b )
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+unsigned short *a, *b;
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+{
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+register unsigned short *p, *q;
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+int i;
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+
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+q = b;
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+p = a + (NE-1); /* point to last word of external number */
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+/* get the sign bit */
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+if( *p & 0x8000 )
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+ *q++ = 0xffff;
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+else
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+ *q++ = 0;
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+/* get the exponent */
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+*q = *p--;
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+*q++ &= 0x7fff; /* delete the sign bit */
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+#ifdef INFINITY
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+if( (*(q-1) & 0x7fff) == 0x7fff )
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+ {
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+#ifdef NANS
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+ if( eisnan(a) )
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+ {
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+ *q++ = 0;
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+ for( i=3; i<NI; i++ )
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+ *q++ = *p--;
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+ return;
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+ }
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+#endif
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+ for( i=2; i<NI; i++ )
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+ *q++ = 0;
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+ return;
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+ }
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+#endif
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+/* clear high guard word */
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+*q++ = 0;
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+/* move in the significand */
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+for( i=0; i<NE-1; i++ )
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+ *q++ = *p--;
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+/* clear low guard word */
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+*q = 0;
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+}
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+
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+
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+/* Move internal format number out,
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+ * converting it to external format.
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+ */
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+void emovo( a, b )
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+unsigned short *a, *b;
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+{
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+register unsigned short *p, *q;
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+unsigned short i;
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+
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+p = a;
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+q = b + (NE-1); /* point to output exponent */
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+/* combine sign and exponent */
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+i = *p++;
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+if( i )
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+ *q-- = *p++ | 0x8000;
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+else
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+ *q-- = *p++;
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+#ifdef INFINITY
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+if( *(p-1) == 0x7fff )
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+ {
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+#ifdef NANS
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+ if( eiisnan(a) )
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+ {
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+ enan( b, NBITS );
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+ return;
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+ }
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+#endif
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+ einfin(b);
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+ return;
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+ }
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+#endif
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+/* skip over guard word */
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+++p;
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+/* move the significand */
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+for( i=0; i<NE-1; i++ )
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+ *q-- = *p++;
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+}
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|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Clear out internal format number.
|
|
|
+ */
|
|
|
+
|
|
|
+void ecleaz( xi )
|
|
|
+register unsigned short *xi;
|
|
|
+{
|
|
|
+register int i;
|
|
|
+
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ *xi++ = 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* same, but don't touch the sign. */
|
|
|
+
|
|
|
+void ecleazs( xi )
|
|
|
+register unsigned short *xi;
|
|
|
+{
|
|
|
+register int i;
|
|
|
+
|
|
|
+++xi;
|
|
|
+for(i=0; i<NI-1; i++)
|
|
|
+ *xi++ = 0;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Move internal format number from a to b.
|
|
|
+ */
|
|
|
+void emovz( a, b )
|
|
|
+register unsigned short *a, *b;
|
|
|
+{
|
|
|
+register int i;
|
|
|
+
|
|
|
+for( i=0; i<NI-1; i++ )
|
|
|
+ *b++ = *a++;
|
|
|
+/* clear low guard word */
|
|
|
+*b = 0;
|
|
|
+}
|
|
|
+
|
|
|
+/* Return nonzero if internal format number is a NaN.
|
|
|
+ */
|
|
|
+
|
|
|
+int eiisnan (x)
|
|
|
+unsigned short x[];
|
|
|
+{
|
|
|
+int i;
|
|
|
+
|
|
|
+if( (x[E] & 0x7fff) == 0x7fff )
|
|
|
+ {
|
|
|
+ for( i=M+1; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( x[i] != 0 )
|
|
|
+ return(1);
|
|
|
+ }
|
|
|
+ }
|
|
|
+return(0);
|
|
|
+}
|
|
|
+
|
|
|
+#ifdef INFINITY
|
|
|
+/* Return nonzero if internal format number is infinite. */
|
|
|
+
|
|
|
+static int
|
|
|
+eiisinf (x)
|
|
|
+ unsigned short x[];
|
|
|
+{
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+ if (eiisnan (x))
|
|
|
+ return (0);
|
|
|
+#endif
|
|
|
+ if ((x[E] & 0x7fff) == 0x7fff)
|
|
|
+ return (1);
|
|
|
+ return (0);
|
|
|
+}
|
|
|
+#endif
|
|
|
+
|
|
|
+/*
|
|
|
+; Compare significands of numbers in internal format.
|
|
|
+; Guard words are included in the comparison.
|
|
|
+;
|
|
|
+; unsigned short a[NI], b[NI];
|
|
|
+; cmpm( a, b );
|
|
|
+;
|
|
|
+; for the significands:
|
|
|
+; returns +1 if a > b
|
|
|
+; 0 if a == b
|
|
|
+; -1 if a < b
|
|
|
+*/
|
|
|
+int ecmpm( a, b )
|
|
|
+register unsigned short *a, *b;
|
|
|
+{
|
|
|
+int i;
|
|
|
+
|
|
|
+a += M; /* skip up to significand area */
|
|
|
+b += M;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *a++ != *b++ )
|
|
|
+ goto difrnt;
|
|
|
+ }
|
|
|
+return(0);
|
|
|
+
|
|
|
+difrnt:
|
|
|
+if( *(--a) > *(--b) )
|
|
|
+ return(1);
|
|
|
+else
|
|
|
+ return(-1);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand down by 1 bit
|
|
|
+*/
|
|
|
+
|
|
|
+void eshdn1(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+register unsigned short bits;
|
|
|
+int i;
|
|
|
+
|
|
|
+x += M; /* point to significand area */
|
|
|
+
|
|
|
+bits = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *x & 1 )
|
|
|
+ bits |= 1;
|
|
|
+ *x >>= 1;
|
|
|
+ if( bits & 2 )
|
|
|
+ *x |= 0x8000;
|
|
|
+ bits <<= 1;
|
|
|
+ ++x;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand up by 1 bit
|
|
|
+*/
|
|
|
+
|
|
|
+void eshup1(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+register unsigned short bits;
|
|
|
+int i;
|
|
|
+
|
|
|
+x += NI-1;
|
|
|
+bits = 0;
|
|
|
+
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *x & 0x8000 )
|
|
|
+ bits |= 1;
|
|
|
+ *x <<= 1;
|
|
|
+ if( bits & 2 )
|
|
|
+ *x |= 1;
|
|
|
+ bits <<= 1;
|
|
|
+ --x;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand down by 8 bits
|
|
|
+*/
|
|
|
+
|
|
|
+void eshdn8(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+register unsigned short newbyt, oldbyt;
|
|
|
+int i;
|
|
|
+
|
|
|
+x += M;
|
|
|
+oldbyt = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ newbyt = *x << 8;
|
|
|
+ *x >>= 8;
|
|
|
+ *x |= oldbyt;
|
|
|
+ oldbyt = newbyt;
|
|
|
+ ++x;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand up by 8 bits
|
|
|
+*/
|
|
|
+
|
|
|
+void eshup8(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+int i;
|
|
|
+register unsigned short newbyt, oldbyt;
|
|
|
+
|
|
|
+x += NI-1;
|
|
|
+oldbyt = 0;
|
|
|
+
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ newbyt = *x >> 8;
|
|
|
+ *x <<= 8;
|
|
|
+ *x |= oldbyt;
|
|
|
+ oldbyt = newbyt;
|
|
|
+ --x;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand up by 16 bits
|
|
|
+*/
|
|
|
+
|
|
|
+void eshup6(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+int i;
|
|
|
+register unsigned short *p;
|
|
|
+
|
|
|
+p = x + M;
|
|
|
+x += M + 1;
|
|
|
+
|
|
|
+for( i=M; i<NI-1; i++ )
|
|
|
+ *p++ = *x++;
|
|
|
+
|
|
|
+*p = 0;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand down by 16 bits
|
|
|
+*/
|
|
|
+
|
|
|
+void eshdn6(x)
|
|
|
+register unsigned short *x;
|
|
|
+{
|
|
|
+int i;
|
|
|
+register unsigned short *p;
|
|
|
+
|
|
|
+x += NI-1;
|
|
|
+p = x + 1;
|
|
|
+
|
|
|
+for( i=M; i<NI-1; i++ )
|
|
|
+ *(--p) = *(--x);
|
|
|
+
|
|
|
+*(--p) = 0;
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; Add significands
|
|
|
+; x + y replaces y
|
|
|
+*/
|
|
|
+
|
|
|
+void eaddm( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+register unsigned long a;
|
|
|
+int i;
|
|
|
+unsigned int carry;
|
|
|
+
|
|
|
+x += NI-1;
|
|
|
+y += NI-1;
|
|
|
+carry = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ a = (unsigned long )(*x) + (unsigned long )(*y) + carry;
|
|
|
+ if( a & 0x10000 )
|
|
|
+ carry = 1;
|
|
|
+ else
|
|
|
+ carry = 0;
|
|
|
+ *y = (unsigned short )a;
|
|
|
+ --x;
|
|
|
+ --y;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; Subtract significands
|
|
|
+; y - x replaces y
|
|
|
+*/
|
|
|
+
|
|
|
+void esubm( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+unsigned long a;
|
|
|
+int i;
|
|
|
+unsigned int carry;
|
|
|
+
|
|
|
+x += NI-1;
|
|
|
+y += NI-1;
|
|
|
+carry = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ a = (unsigned long )(*y) - (unsigned long )(*x) - carry;
|
|
|
+ if( a & 0x10000 )
|
|
|
+ carry = 1;
|
|
|
+ else
|
|
|
+ carry = 0;
|
|
|
+ *y = (unsigned short )a;
|
|
|
+ --x;
|
|
|
+ --y;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* Divide significands */
|
|
|
+
|
|
|
+static unsigned short equot[NI] = {0}; /* was static */
|
|
|
+
|
|
|
+#if 0
|
|
|
+int edivm( den, num )
|
|
|
+unsigned short den[], num[];
|
|
|
+{
|
|
|
+int i;
|
|
|
+register unsigned short *p, *q;
|
|
|
+unsigned short j;
|
|
|
+
|
|
|
+p = &equot[0];
|
|
|
+*p++ = num[0];
|
|
|
+*p++ = num[1];
|
|
|
+
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ *p++ = 0;
|
|
|
+ }
|
|
|
+
|
|
|
+/* Use faster compare and subtraction if denominator
|
|
|
+ * has only 15 bits of significance.
|
|
|
+ */
|
|
|
+p = &den[M+2];
|
|
|
+if( *p++ == 0 )
|
|
|
+ {
|
|
|
+ for( i=M+3; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *p++ != 0 )
|
|
|
+ goto fulldiv;
|
|
|
+ }
|
|
|
+ if( (den[M+1] & 1) != 0 )
|
|
|
+ goto fulldiv;
|
|
|
+ eshdn1(num);
|
|
|
+ eshdn1(den);
|
|
|
+
|
|
|
+ p = &den[M+1];
|
|
|
+ q = &num[M+1];
|
|
|
+
|
|
|
+ for( i=0; i<NBITS+2; i++ )
|
|
|
+ {
|
|
|
+ if( *p <= *q )
|
|
|
+ {
|
|
|
+ *q -= *p;
|
|
|
+ j = 1;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ j = 0;
|
|
|
+ }
|
|
|
+ eshup1(equot);
|
|
|
+ equot[NI-2] |= j;
|
|
|
+ eshup1(num);
|
|
|
+ }
|
|
|
+ goto divdon;
|
|
|
+ }
|
|
|
+
|
|
|
+/* The number of quotient bits to calculate is
|
|
|
+ * NBITS + 1 scaling guard bit + 1 roundoff bit.
|
|
|
+ */
|
|
|
+fulldiv:
|
|
|
+
|
|
|
+p = &equot[NI-2];
|
|
|
+for( i=0; i<NBITS+2; i++ )
|
|
|
+ {
|
|
|
+ if( ecmpm(den,num) <= 0 )
|
|
|
+ {
|
|
|
+ esubm(den, num);
|
|
|
+ j = 1; /* quotient bit = 1 */
|
|
|
+ }
|
|
|
+ else
|
|
|
+ j = 0;
|
|
|
+ eshup1(equot);
|
|
|
+ *p |= j;
|
|
|
+ eshup1(num);
|
|
|
+ }
|
|
|
+
|
|
|
+divdon:
|
|
|
+
|
|
|
+eshdn1( equot );
|
|
|
+eshdn1( equot );
|
|
|
+
|
|
|
+/* test for nonzero remainder after roundoff bit */
|
|
|
+p = &num[M];
|
|
|
+j = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ j |= *p++;
|
|
|
+ }
|
|
|
+if( j )
|
|
|
+ j = 1;
|
|
|
+
|
|
|
+
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ num[i] = equot[i];
|
|
|
+return( (int )j );
|
|
|
+}
|
|
|
+
|
|
|
+/* Multiply significands */
|
|
|
+int emulm( a, b )
|
|
|
+unsigned short a[], b[];
|
|
|
+{
|
|
|
+unsigned short *p, *q;
|
|
|
+int i, j, k;
|
|
|
+
|
|
|
+equot[0] = b[0];
|
|
|
+equot[1] = b[1];
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ equot[i] = 0;
|
|
|
+
|
|
|
+p = &a[NI-2];
|
|
|
+k = NBITS;
|
|
|
+while( *p == 0 ) /* significand is not supposed to be all zero */
|
|
|
+ {
|
|
|
+ eshdn6(a);
|
|
|
+ k -= 16;
|
|
|
+ }
|
|
|
+if( (*p & 0xff) == 0 )
|
|
|
+ {
|
|
|
+ eshdn8(a);
|
|
|
+ k -= 8;
|
|
|
+ }
|
|
|
+
|
|
|
+q = &equot[NI-1];
|
|
|
+j = 0;
|
|
|
+for( i=0; i<k; i++ )
|
|
|
+ {
|
|
|
+ if( *p & 1 )
|
|
|
+ eaddm(b, equot);
|
|
|
+/* remember if there were any nonzero bits shifted out */
|
|
|
+ if( *q & 1 )
|
|
|
+ j |= 1;
|
|
|
+ eshdn1(a);
|
|
|
+ eshdn1(equot);
|
|
|
+ }
|
|
|
+
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ b[i] = equot[i];
|
|
|
+
|
|
|
+/* return flag for lost nonzero bits */
|
|
|
+return(j);
|
|
|
+}
|
|
|
+
|
|
|
+#else
|
|
|
+
|
|
|
+/* Multiply significand of e-type number b
|
|
|
+by 16-bit quantity a, e-type result to c. */
|
|
|
+
|
|
|
+void m16m( a, b, c )
|
|
|
+unsigned short a;
|
|
|
+unsigned short b[], c[];
|
|
|
+{
|
|
|
+register unsigned short *pp;
|
|
|
+register unsigned long carry;
|
|
|
+unsigned short *ps;
|
|
|
+unsigned short p[NI];
|
|
|
+unsigned long aa, m;
|
|
|
+int i;
|
|
|
+
|
|
|
+aa = a;
|
|
|
+pp = &p[NI-2];
|
|
|
+*pp++ = 0;
|
|
|
+*pp = 0;
|
|
|
+ps = &b[NI-1];
|
|
|
+
|
|
|
+for( i=M+1; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *ps == 0 )
|
|
|
+ {
|
|
|
+ --ps;
|
|
|
+ --pp;
|
|
|
+ *(pp-1) = 0;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ m = (unsigned long) aa * *ps--;
|
|
|
+ carry = (m & 0xffff) + *pp;
|
|
|
+ *pp-- = (unsigned short )carry;
|
|
|
+ carry = (carry >> 16) + (m >> 16) + *pp;
|
|
|
+ *pp = (unsigned short )carry;
|
|
|
+ *(pp-1) = carry >> 16;
|
|
|
+ }
|
|
|
+ }
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ c[i] = p[i];
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* Divide significands. Neither the numerator nor the denominator
|
|
|
+is permitted to have its high guard word nonzero. */
|
|
|
+
|
|
|
+
|
|
|
+int edivm( den, num )
|
|
|
+unsigned short den[], num[];
|
|
|
+{
|
|
|
+int i;
|
|
|
+register unsigned short *p;
|
|
|
+unsigned long tnum;
|
|
|
+unsigned short j, tdenm, tquot;
|
|
|
+unsigned short tprod[NI+1];
|
|
|
+
|
|
|
+p = &equot[0];
|
|
|
+*p++ = num[0];
|
|
|
+*p++ = num[1];
|
|
|
+
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ *p++ = 0;
|
|
|
+ }
|
|
|
+eshdn1( num );
|
|
|
+tdenm = den[M+1];
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ /* Find trial quotient digit (the radix is 65536). */
|
|
|
+ tnum = (((unsigned long) num[M]) << 16) + num[M+1];
|
|
|
+
|
|
|
+ /* Do not execute the divide instruction if it will overflow. */
|
|
|
+ if( (tdenm * 0xffffL) < tnum )
|
|
|
+ tquot = 0xffff;
|
|
|
+ else
|
|
|
+ tquot = tnum / tdenm;
|
|
|
+
|
|
|
+ /* Prove that the divide worked. */
|
|
|
+/*
|
|
|
+ tcheck = (unsigned long )tquot * tdenm;
|
|
|
+ if( tnum - tcheck > tdenm )
|
|
|
+ tquot = 0xffff;
|
|
|
+*/
|
|
|
+ /* Multiply denominator by trial quotient digit. */
|
|
|
+ m16m( tquot, den, tprod );
|
|
|
+ /* The quotient digit may have been overestimated. */
|
|
|
+ if( ecmpm( tprod, num ) > 0 )
|
|
|
+ {
|
|
|
+ tquot -= 1;
|
|
|
+ esubm( den, tprod );
|
|
|
+ if( ecmpm( tprod, num ) > 0 )
|
|
|
+ {
|
|
|
+ tquot -= 1;
|
|
|
+ esubm( den, tprod );
|
|
|
+ }
|
|
|
+ }
|
|
|
+/*
|
|
|
+ if( ecmpm( tprod, num ) > 0 )
|
|
|
+ {
|
|
|
+ eshow( "tprod", tprod );
|
|
|
+ eshow( "num ", num );
|
|
|
+ printf( "tnum = %08lx, tden = %04x, tquot = %04x\n",
|
|
|
+ tnum, den[M+1], tquot );
|
|
|
+ }
|
|
|
+*/
|
|
|
+ esubm( tprod, num );
|
|
|
+/*
|
|
|
+ if( ecmpm( num, den ) >= 0 )
|
|
|
+ {
|
|
|
+ eshow( "num ", num );
|
|
|
+ eshow( "den ", den );
|
|
|
+ printf( "tnum = %08lx, tden = %04x, tquot = %04x\n",
|
|
|
+ tnum, den[M+1], tquot );
|
|
|
+ }
|
|
|
+*/
|
|
|
+ equot[i] = tquot;
|
|
|
+ eshup6(num);
|
|
|
+ }
|
|
|
+/* test for nonzero remainder after roundoff bit */
|
|
|
+p = &num[M];
|
|
|
+j = 0;
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ {
|
|
|
+ j |= *p++;
|
|
|
+ }
|
|
|
+if( j )
|
|
|
+ j = 1;
|
|
|
+
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ num[i] = equot[i];
|
|
|
+
|
|
|
+return( (int )j );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Multiply significands */
|
|
|
+int emulm( a, b )
|
|
|
+unsigned short a[], b[];
|
|
|
+{
|
|
|
+unsigned short *p, *q;
|
|
|
+unsigned short pprod[NI];
|
|
|
+unsigned short j;
|
|
|
+int i;
|
|
|
+
|
|
|
+equot[0] = b[0];
|
|
|
+equot[1] = b[1];
|
|
|
+for( i=M; i<NI; i++ )
|
|
|
+ equot[i] = 0;
|
|
|
+
|
|
|
+j = 0;
|
|
|
+p = &a[NI-1];
|
|
|
+q = &equot[NI-1];
|
|
|
+for( i=M+1; i<NI; i++ )
|
|
|
+ {
|
|
|
+ if( *p == 0 )
|
|
|
+ {
|
|
|
+ --p;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ m16m( *p--, b, pprod );
|
|
|
+ eaddm(pprod, equot);
|
|
|
+ }
|
|
|
+ j |= *q;
|
|
|
+ eshdn6(equot);
|
|
|
+ }
|
|
|
+
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ b[i] = equot[i];
|
|
|
+
|
|
|
+/* return flag for lost nonzero bits */
|
|
|
+return( (int)j );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+eshow(str, x)
|
|
|
+char *str;
|
|
|
+unsigned short *x;
|
|
|
+{
|
|
|
+int i;
|
|
|
+
|
|
|
+printf( "%s ", str );
|
|
|
+for( i=0; i<NI; i++ )
|
|
|
+ printf( "%04x ", *x++ );
|
|
|
+printf( "\n" );
|
|
|
+}
|
|
|
+*/
|
|
|
+#endif
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+ * Normalize and round off.
|
|
|
+ *
|
|
|
+ * The internal format number to be rounded is "s".
|
|
|
+ * Input "lost" indicates whether the number is exact.
|
|
|
+ * This is the so-called sticky bit.
|
|
|
+ *
|
|
|
+ * Input "subflg" indicates whether the number was obtained
|
|
|
+ * by a subtraction operation. In that case if lost is nonzero
|
|
|
+ * then the number is slightly smaller than indicated.
|
|
|
+ *
|
|
|
+ * Input "exp" is the biased exponent, which may be negative.
|
|
|
+ * the exponent field of "s" is ignored but is replaced by
|
|
|
+ * "exp" as adjusted by normalization and rounding.
|
|
|
+ *
|
|
|
+ * Input "rcntrl" is the rounding control.
|
|
|
+ */
|
|
|
+
|
|
|
+static int rlast = -1;
|
|
|
+static int rw = 0;
|
|
|
+static unsigned short rmsk = 0;
|
|
|
+static unsigned short rmbit = 0;
|
|
|
+static unsigned short rebit = 0;
|
|
|
+static int re = 0;
|
|
|
+static unsigned short rbit[NI] = {0,0,0,0,0,0,0,0};
|
|
|
+
|
|
|
+void emdnorm( s, lost, subflg, exp, rcntrl )
|
|
|
+unsigned short s[];
|
|
|
+int lost;
|
|
|
+int subflg;
|
|
|
+long exp;
|
|
|
+int rcntrl;
|
|
|
+{
|
|
|
+int i, j;
|
|
|
+unsigned short r;
|
|
|
+
|
|
|
+/* Normalize */
|
|
|
+j = enormlz( s );
|
|
|
+
|
|
|
+/* a blank significand could mean either zero or infinity. */
|
|
|
+#ifndef INFINITY
|
|
|
+if( j > NBITS )
|
|
|
+ {
|
|
|
+ ecleazs( s );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+exp -= j;
|
|
|
+#ifndef INFINITY
|
|
|
+if( exp >= 32767L )
|
|
|
+ goto overf;
|
|
|
+#else
|
|
|
+if( (j > NBITS) && (exp < 32767L) )
|
|
|
+ {
|
|
|
+ ecleazs( s );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+if( exp < 0L )
|
|
|
+ {
|
|
|
+ if( exp > (long )(-NBITS-1) )
|
|
|
+ {
|
|
|
+ j = (int )exp;
|
|
|
+ i = eshift( s, j );
|
|
|
+ if( i )
|
|
|
+ lost = 1;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ ecleazs( s );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ }
|
|
|
+/* Round off, unless told not to by rcntrl. */
|
|
|
+if( rcntrl == 0 )
|
|
|
+ goto mdfin;
|
|
|
+/* Set up rounding parameters if the control register changed. */
|
|
|
+if( rndprc != rlast )
|
|
|
+ {
|
|
|
+ ecleaz( rbit );
|
|
|
+ switch( rndprc )
|
|
|
+ {
|
|
|
+ default:
|
|
|
+ case NBITS:
|
|
|
+ rw = NI-1; /* low guard word */
|
|
|
+ rmsk = 0xffff;
|
|
|
+ rmbit = 0x8000;
|
|
|
+ rebit = 1;
|
|
|
+ re = rw - 1;
|
|
|
+ break;
|
|
|
+ case 113:
|
|
|
+ rw = 10;
|
|
|
+ rmsk = 0x7fff;
|
|
|
+ rmbit = 0x4000;
|
|
|
+ rebit = 0x8000;
|
|
|
+ re = rw;
|
|
|
+ break;
|
|
|
+ case 64:
|
|
|
+ rw = 7;
|
|
|
+ rmsk = 0xffff;
|
|
|
+ rmbit = 0x8000;
|
|
|
+ rebit = 1;
|
|
|
+ re = rw-1;
|
|
|
+ break;
|
|
|
+/* For DEC arithmetic */
|
|
|
+ case 56:
|
|
|
+ rw = 6;
|
|
|
+ rmsk = 0xff;
|
|
|
+ rmbit = 0x80;
|
|
|
+ rebit = 0x100;
|
|
|
+ re = rw;
|
|
|
+ break;
|
|
|
+ case 53:
|
|
|
+ rw = 6;
|
|
|
+ rmsk = 0x7ff;
|
|
|
+ rmbit = 0x0400;
|
|
|
+ rebit = 0x800;
|
|
|
+ re = rw;
|
|
|
+ break;
|
|
|
+ case 24:
|
|
|
+ rw = 4;
|
|
|
+ rmsk = 0xff;
|
|
|
+ rmbit = 0x80;
|
|
|
+ rebit = 0x100;
|
|
|
+ re = rw;
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ rbit[re] = rebit;
|
|
|
+ rlast = rndprc;
|
|
|
+ }
|
|
|
+
|
|
|
+/* Shift down 1 temporarily if the data structure has an implied
|
|
|
+ * most significant bit and the number is denormal.
|
|
|
+ * For rndprc = 64 or NBITS, there is no implied bit.
|
|
|
+ * But Intel long double denormals lose one bit of significance even so.
|
|
|
+ */
|
|
|
+#if IBMPC
|
|
|
+if( (exp <= 0) && (rndprc != NBITS) )
|
|
|
+#else
|
|
|
+if( (exp <= 0) && (rndprc != 64) && (rndprc != NBITS) )
|
|
|
+#endif
|
|
|
+ {
|
|
|
+ lost |= s[NI-1] & 1;
|
|
|
+ eshdn1(s);
|
|
|
+ }
|
|
|
+/* Clear out all bits below the rounding bit,
|
|
|
+ * remembering in r if any were nonzero.
|
|
|
+ */
|
|
|
+r = s[rw] & rmsk;
|
|
|
+if( rndprc < NBITS )
|
|
|
+ {
|
|
|
+ i = rw + 1;
|
|
|
+ while( i < NI )
|
|
|
+ {
|
|
|
+ if( s[i] )
|
|
|
+ r |= 1;
|
|
|
+ s[i] = 0;
|
|
|
+ ++i;
|
|
|
+ }
|
|
|
+ }
|
|
|
+s[rw] &= ~rmsk;
|
|
|
+if( (r & rmbit) != 0 )
|
|
|
+ {
|
|
|
+ if( r == rmbit )
|
|
|
+ {
|
|
|
+ if( lost == 0 )
|
|
|
+ { /* round to even */
|
|
|
+ if( (s[re] & rebit) == 0 )
|
|
|
+ goto mddone;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ if( subflg != 0 )
|
|
|
+ goto mddone;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ eaddm( rbit, s );
|
|
|
+ }
|
|
|
+mddone:
|
|
|
+#if IBMPC
|
|
|
+if( (exp <= 0) && (rndprc != NBITS) )
|
|
|
+#else
|
|
|
+if( (exp <= 0) && (rndprc != 64) && (rndprc != NBITS) )
|
|
|
+#endif
|
|
|
+ {
|
|
|
+ eshup1(s);
|
|
|
+ }
|
|
|
+if( s[2] != 0 )
|
|
|
+ { /* overflow on roundoff */
|
|
|
+ eshdn1(s);
|
|
|
+ exp += 1;
|
|
|
+ }
|
|
|
+mdfin:
|
|
|
+s[NI-1] = 0;
|
|
|
+if( exp >= 32767L )
|
|
|
+ {
|
|
|
+#ifndef INFINITY
|
|
|
+overf:
|
|
|
+#endif
|
|
|
+#ifdef INFINITY
|
|
|
+ s[1] = 32767;
|
|
|
+ for( i=2; i<NI-1; i++ )
|
|
|
+ s[i] = 0;
|
|
|
+#else
|
|
|
+ s[1] = 32766;
|
|
|
+ s[2] = 0;
|
|
|
+ for( i=M+1; i<NI-1; i++ )
|
|
|
+ s[i] = 0xffff;
|
|
|
+ s[NI-1] = 0;
|
|
|
+ if( (rndprc < 64) || (rndprc == 113) )
|
|
|
+ {
|
|
|
+ s[rw] &= ~rmsk;
|
|
|
+ if( rndprc == 24 )
|
|
|
+ {
|
|
|
+ s[5] = 0;
|
|
|
+ s[6] = 0;
|
|
|
+ }
|
|
|
+ }
|
|
|
+#endif
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( exp < 0 )
|
|
|
+ s[1] = 0;
|
|
|
+else
|
|
|
+ s[1] = (unsigned short )exp;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Subtract external format numbers.
|
|
|
+;
|
|
|
+; unsigned short a[NE], b[NE], c[NE];
|
|
|
+; esub( a, b, c ); c = b - a
|
|
|
+*/
|
|
|
+
|
|
|
+static int subflg = 0;
|
|
|
+
|
|
|
+void esub( a, b, c )
|
|
|
+unsigned short *a, *b, *c;
|
|
|
+{
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(a) )
|
|
|
+ {
|
|
|
+ emov (a, c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisnan(b) )
|
|
|
+ {
|
|
|
+ emov(b,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+/* Infinity minus infinity is a NaN.
|
|
|
+ * Test for subtracting infinities of the same sign.
|
|
|
+ */
|
|
|
+if( eisinf(a) && eisinf(b) && ((eisneg (a) ^ eisneg (b)) == 0))
|
|
|
+ {
|
|
|
+ mtherr( "esub", DOMAIN );
|
|
|
+ enan( c, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+subflg = 1;
|
|
|
+eadd1( a, b, c );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Add.
|
|
|
+;
|
|
|
+; unsigned short a[NE], b[NE], c[NE];
|
|
|
+; eadd( a, b, c ); c = b + a
|
|
|
+*/
|
|
|
+void eadd( a, b, c )
|
|
|
+unsigned short *a, *b, *c;
|
|
|
+{
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+/* NaN plus anything is a NaN. */
|
|
|
+if( eisnan(a) )
|
|
|
+ {
|
|
|
+ emov(a,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisnan(b) )
|
|
|
+ {
|
|
|
+ emov(b,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+/* Infinity minus infinity is a NaN.
|
|
|
+ * Test for adding infinities of opposite signs.
|
|
|
+ */
|
|
|
+if( eisinf(a) && eisinf(b)
|
|
|
+ && ((eisneg(a) ^ eisneg(b)) != 0) )
|
|
|
+ {
|
|
|
+ mtherr( "eadd", DOMAIN );
|
|
|
+ enan( c, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+subflg = 0;
|
|
|
+eadd1( a, b, c );
|
|
|
+}
|
|
|
+
|
|
|
+void eadd1( a, b, c )
|
|
|
+unsigned short *a, *b, *c;
|
|
|
+{
|
|
|
+unsigned short ai[NI], bi[NI], ci[NI];
|
|
|
+int i, lost, j, k;
|
|
|
+long lt, lta, ltb;
|
|
|
+
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(a) )
|
|
|
+ {
|
|
|
+ emov(a,c);
|
|
|
+ if( subflg )
|
|
|
+ eneg(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisinf(b) )
|
|
|
+ {
|
|
|
+ emov(b,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( a, ai );
|
|
|
+emovi( b, bi );
|
|
|
+if( subflg )
|
|
|
+ ai[0] = ~ai[0];
|
|
|
+
|
|
|
+/* compare exponents */
|
|
|
+lta = ai[E];
|
|
|
+ltb = bi[E];
|
|
|
+lt = lta - ltb;
|
|
|
+if( lt > 0L )
|
|
|
+ { /* put the larger number in bi */
|
|
|
+ emovz( bi, ci );
|
|
|
+ emovz( ai, bi );
|
|
|
+ emovz( ci, ai );
|
|
|
+ ltb = bi[E];
|
|
|
+ lt = -lt;
|
|
|
+ }
|
|
|
+lost = 0;
|
|
|
+if( lt != 0L )
|
|
|
+ {
|
|
|
+ if( lt < (long )(-NBITS-1) )
|
|
|
+ goto done; /* answer same as larger addend */
|
|
|
+ k = (int )lt;
|
|
|
+ lost = eshift( ai, k ); /* shift the smaller number down */
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+/* exponents were the same, so must compare significands */
|
|
|
+ i = ecmpm( ai, bi );
|
|
|
+ if( i == 0 )
|
|
|
+ { /* the numbers are identical in magnitude */
|
|
|
+ /* if different signs, result is zero */
|
|
|
+ if( ai[0] != bi[0] )
|
|
|
+ {
|
|
|
+ eclear(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ /* if same sign, result is double */
|
|
|
+ /* double denomalized tiny number */
|
|
|
+ if( (bi[E] == 0) && ((bi[3] & 0x8000) == 0) )
|
|
|
+ {
|
|
|
+ eshup1( bi );
|
|
|
+ goto done;
|
|
|
+ }
|
|
|
+ /* add 1 to exponent unless both are zero! */
|
|
|
+ for( j=1; j<NI-1; j++ )
|
|
|
+ {
|
|
|
+ if( bi[j] != 0 )
|
|
|
+ {
|
|
|
+/* This could overflow, but let emovo take care of that. */
|
|
|
+ ltb += 1;
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ bi[E] = (unsigned short )ltb;
|
|
|
+ goto done;
|
|
|
+ }
|
|
|
+ if( i > 0 )
|
|
|
+ { /* put the larger number in bi */
|
|
|
+ emovz( bi, ci );
|
|
|
+ emovz( ai, bi );
|
|
|
+ emovz( ci, ai );
|
|
|
+ }
|
|
|
+ }
|
|
|
+if( ai[0] == bi[0] )
|
|
|
+ {
|
|
|
+ eaddm( ai, bi );
|
|
|
+ subflg = 0;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ esubm( ai, bi );
|
|
|
+ subflg = 1;
|
|
|
+ }
|
|
|
+emdnorm( bi, lost, subflg, ltb, 64 );
|
|
|
+
|
|
|
+done:
|
|
|
+emovo( bi, c );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Divide.
|
|
|
+;
|
|
|
+; unsigned short a[NE], b[NE], c[NE];
|
|
|
+; ediv( a, b, c ); c = b / a
|
|
|
+*/
|
|
|
+void ediv( a, b, c )
|
|
|
+unsigned short *a, *b, *c;
|
|
|
+{
|
|
|
+unsigned short ai[NI], bi[NI];
|
|
|
+int i;
|
|
|
+long lt, lta, ltb;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+/* Return any NaN input. */
|
|
|
+if( eisnan(a) )
|
|
|
+ {
|
|
|
+ emov(a,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisnan(b) )
|
|
|
+ {
|
|
|
+ emov(b,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+/* Zero over zero, or infinity over infinity, is a NaN. */
|
|
|
+if( ((ecmp(a,ezero) == 0) && (ecmp(b,ezero) == 0))
|
|
|
+ || (eisinf (a) && eisinf (b)) )
|
|
|
+ {
|
|
|
+ mtherr( "ediv", DOMAIN );
|
|
|
+ enan( c, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+/* Infinity over anything else is infinity. */
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(b) )
|
|
|
+ {
|
|
|
+ if( eisneg(a) ^ eisneg(b) )
|
|
|
+ *(c+(NE-1)) = 0x8000;
|
|
|
+ else
|
|
|
+ *(c+(NE-1)) = 0;
|
|
|
+ einfin(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisinf(a) )
|
|
|
+ {
|
|
|
+ eclear(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( a, ai );
|
|
|
+emovi( b, bi );
|
|
|
+lta = ai[E];
|
|
|
+ltb = bi[E];
|
|
|
+if( bi[E] == 0 )
|
|
|
+ { /* See if numerator is zero. */
|
|
|
+ for( i=1; i<NI-1; i++ )
|
|
|
+ {
|
|
|
+ if( bi[i] != 0 )
|
|
|
+ {
|
|
|
+ ltb -= enormlz( bi );
|
|
|
+ goto dnzro1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ eclear(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+dnzro1:
|
|
|
+
|
|
|
+if( ai[E] == 0 )
|
|
|
+ { /* possible divide by zero */
|
|
|
+ for( i=1; i<NI-1; i++ )
|
|
|
+ {
|
|
|
+ if( ai[i] != 0 )
|
|
|
+ {
|
|
|
+ lta -= enormlz( ai );
|
|
|
+ goto dnzro2;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ if( ai[0] == bi[0] )
|
|
|
+ *(c+(NE-1)) = 0;
|
|
|
+ else
|
|
|
+ *(c+(NE-1)) = 0x8000;
|
|
|
+ einfin(c);
|
|
|
+ mtherr( "ediv", SING );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+dnzro2:
|
|
|
+
|
|
|
+i = edivm( ai, bi );
|
|
|
+/* calculate exponent */
|
|
|
+lt = ltb - lta + EXONE;
|
|
|
+emdnorm( bi, i, 0, lt, 64 );
|
|
|
+/* set the sign */
|
|
|
+if( ai[0] == bi[0] )
|
|
|
+ bi[0] = 0;
|
|
|
+else
|
|
|
+ bi[0] = 0Xffff;
|
|
|
+emovo( bi, c );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Multiply.
|
|
|
+;
|
|
|
+; unsigned short a[NE], b[NE], c[NE];
|
|
|
+; emul( a, b, c ); c = b * a
|
|
|
+*/
|
|
|
+void emul( a, b, c )
|
|
|
+unsigned short *a, *b, *c;
|
|
|
+{
|
|
|
+unsigned short ai[NI], bi[NI];
|
|
|
+int i, j;
|
|
|
+long lt, lta, ltb;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+/* NaN times anything is the same NaN. */
|
|
|
+if( eisnan(a) )
|
|
|
+ {
|
|
|
+ emov(a,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( eisnan(b) )
|
|
|
+ {
|
|
|
+ emov(b,c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+/* Zero times infinity is a NaN. */
|
|
|
+if( (eisinf(a) && (ecmp(b,ezero) == 0))
|
|
|
+ || (eisinf(b) && (ecmp(a,ezero) == 0)) )
|
|
|
+ {
|
|
|
+ mtherr( "emul", DOMAIN );
|
|
|
+ enan( c, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+/* Infinity times anything else is infinity. */
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(a) || eisinf(b) )
|
|
|
+ {
|
|
|
+ if( eisneg(a) ^ eisneg(b) )
|
|
|
+ *(c+(NE-1)) = 0x8000;
|
|
|
+ else
|
|
|
+ *(c+(NE-1)) = 0;
|
|
|
+ einfin(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( a, ai );
|
|
|
+emovi( b, bi );
|
|
|
+lta = ai[E];
|
|
|
+ltb = bi[E];
|
|
|
+if( ai[E] == 0 )
|
|
|
+ {
|
|
|
+ for( i=1; i<NI-1; i++ )
|
|
|
+ {
|
|
|
+ if( ai[i] != 0 )
|
|
|
+ {
|
|
|
+ lta -= enormlz( ai );
|
|
|
+ goto mnzer1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ eclear(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+mnzer1:
|
|
|
+
|
|
|
+if( bi[E] == 0 )
|
|
|
+ {
|
|
|
+ for( i=1; i<NI-1; i++ )
|
|
|
+ {
|
|
|
+ if( bi[i] != 0 )
|
|
|
+ {
|
|
|
+ ltb -= enormlz( bi );
|
|
|
+ goto mnzer2;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ eclear(c);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+mnzer2:
|
|
|
+
|
|
|
+/* Multiply significands */
|
|
|
+j = emulm( ai, bi );
|
|
|
+/* calculate exponent */
|
|
|
+lt = lta + ltb - (EXONE - 1);
|
|
|
+emdnorm( bi, j, 0, lt, 64 );
|
|
|
+/* calculate sign of product */
|
|
|
+if( ai[0] == bi[0] )
|
|
|
+ bi[0] = 0;
|
|
|
+else
|
|
|
+ bi[0] = 0xffff;
|
|
|
+emovo( bi, c );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Convert IEEE double precision to e type
|
|
|
+; double d;
|
|
|
+; unsigned short x[N+2];
|
|
|
+; e53toe( &d, x );
|
|
|
+*/
|
|
|
+void e53toe( pe, y )
|
|
|
+unsigned short *pe, *y;
|
|
|
+{
|
|
|
+#ifdef DEC
|
|
|
+
|
|
|
+dectoe( pe, y ); /* see etodec.c */
|
|
|
+
|
|
|
+#else
|
|
|
+
|
|
|
+register unsigned short r;
|
|
|
+register unsigned short *p, *e;
|
|
|
+unsigned short yy[NI];
|
|
|
+int denorm, k;
|
|
|
+
|
|
|
+e = pe;
|
|
|
+denorm = 0; /* flag if denormalized number */
|
|
|
+ecleaz(yy);
|
|
|
+#ifdef IBMPC
|
|
|
+e += 3;
|
|
|
+#endif
|
|
|
+r = *e;
|
|
|
+yy[0] = 0;
|
|
|
+if( r & 0x8000 )
|
|
|
+ yy[0] = 0xffff;
|
|
|
+yy[M] = (r & 0x0f) | 0x10;
|
|
|
+r &= ~0x800f; /* strip sign and 4 significand bits */
|
|
|
+#ifdef INFINITY
|
|
|
+if( r == 0x7ff0 )
|
|
|
+ {
|
|
|
+#ifdef NANS
|
|
|
+#ifdef IBMPC
|
|
|
+ if( ((pe[3] & 0xf) != 0) || (pe[2] != 0)
|
|
|
+ || (pe[1] != 0) || (pe[0] != 0) )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#else
|
|
|
+ if( ((pe[0] & 0xf) != 0) || (pe[1] != 0)
|
|
|
+ || (pe[2] != 0) || (pe[3] != 0) )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#endif /* NANS */
|
|
|
+ eclear( y );
|
|
|
+ einfin( y );
|
|
|
+ if( yy[0] )
|
|
|
+ eneg(y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+r >>= 4;
|
|
|
+/* If zero exponent, then the significand is denormalized.
|
|
|
+ * So, take back the understood high significand bit. */
|
|
|
+if( r == 0 )
|
|
|
+ {
|
|
|
+ denorm = 1;
|
|
|
+ yy[M] &= ~0x10;
|
|
|
+ }
|
|
|
+r += EXONE - 01777;
|
|
|
+yy[E] = r;
|
|
|
+p = &yy[M+1];
|
|
|
+#ifdef IBMPC
|
|
|
+*p++ = *(--e);
|
|
|
+*p++ = *(--e);
|
|
|
+*p++ = *(--e);
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+++e;
|
|
|
+*p++ = *e++;
|
|
|
+*p++ = *e++;
|
|
|
+*p++ = *e++;
|
|
|
+#endif
|
|
|
+(void )eshift( yy, -5 );
|
|
|
+if( denorm )
|
|
|
+ { /* if zero exponent, then normalize the significand */
|
|
|
+ if( (k = enormlz(yy)) > NBITS )
|
|
|
+ ecleazs(yy);
|
|
|
+ else
|
|
|
+ yy[E] -= (unsigned short )(k-1);
|
|
|
+ }
|
|
|
+emovo( yy, y );
|
|
|
+#endif /* not DEC */
|
|
|
+}
|
|
|
+
|
|
|
+void e64toe( pe, y )
|
|
|
+unsigned short *pe, *y;
|
|
|
+{
|
|
|
+unsigned short yy[NI];
|
|
|
+unsigned short *p, *q, *e;
|
|
|
+int i;
|
|
|
+
|
|
|
+e = pe;
|
|
|
+p = yy;
|
|
|
+for( i=0; i<NE-5; i++ )
|
|
|
+ *p++ = 0;
|
|
|
+#ifdef IBMPC
|
|
|
+for( i=0; i<5; i++ )
|
|
|
+ *p++ = *e++;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+for( i=0; i<5; i++ )
|
|
|
+ *p++ = *e++;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+p = &yy[0] + (NE-1);
|
|
|
+*p-- = *e++;
|
|
|
+++e;
|
|
|
+for( i=0; i<4; i++ )
|
|
|
+ *p-- = *e++;
|
|
|
+#endif
|
|
|
+
|
|
|
+#ifdef IBMPC
|
|
|
+/* For Intel long double, shift denormal significand up 1
|
|
|
+ -- but only if the top significand bit is zero. */
|
|
|
+if((yy[NE-1] & 0x7fff) == 0 && (yy[NE-2] & 0x8000) == 0)
|
|
|
+ {
|
|
|
+ unsigned short temp[NI+1];
|
|
|
+ emovi(yy, temp);
|
|
|
+ eshup1(temp);
|
|
|
+ emovo(temp,y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#ifdef INFINITY
|
|
|
+/* Point to the exponent field. */
|
|
|
+p = &yy[NE-1];
|
|
|
+if( *p == 0x7fff )
|
|
|
+ {
|
|
|
+#ifdef NANS
|
|
|
+#ifdef IBMPC
|
|
|
+ for( i=0; i<4; i++ )
|
|
|
+ {
|
|
|
+ if((i != 3 && pe[i] != 0)
|
|
|
+ /* Check for Intel long double infinity pattern. */
|
|
|
+ || (i == 3 && pe[i] != 0x8000))
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ }
|
|
|
+#else
|
|
|
+ for( i=1; i<=4; i++ )
|
|
|
+ {
|
|
|
+ if( pe[i] != 0 )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#endif /* NANS */
|
|
|
+ eclear( y );
|
|
|
+ einfin( y );
|
|
|
+ if( *p & 0x8000 )
|
|
|
+ eneg(y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+p = yy;
|
|
|
+q = y;
|
|
|
+for( i=0; i<NE; i++ )
|
|
|
+ *q++ = *p++;
|
|
|
+}
|
|
|
+
|
|
|
+void e113toe(pe,y)
|
|
|
+unsigned short *pe, *y;
|
|
|
+{
|
|
|
+register unsigned short r;
|
|
|
+unsigned short *e, *p;
|
|
|
+unsigned short yy[NI];
|
|
|
+int denorm, i;
|
|
|
+
|
|
|
+e = pe;
|
|
|
+denorm = 0;
|
|
|
+ecleaz(yy);
|
|
|
+#ifdef IBMPC
|
|
|
+e += 7;
|
|
|
+#endif
|
|
|
+r = *e;
|
|
|
+yy[0] = 0;
|
|
|
+if( r & 0x8000 )
|
|
|
+ yy[0] = 0xffff;
|
|
|
+r &= 0x7fff;
|
|
|
+#ifdef INFINITY
|
|
|
+if( r == 0x7fff )
|
|
|
+ {
|
|
|
+#ifdef NANS
|
|
|
+#ifdef IBMPC
|
|
|
+ for( i=0; i<7; i++ )
|
|
|
+ {
|
|
|
+ if( pe[i] != 0 )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ }
|
|
|
+#else
|
|
|
+ for( i=1; i<8; i++ )
|
|
|
+ {
|
|
|
+ if( pe[i] != 0 )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#endif /* NANS */
|
|
|
+ eclear( y );
|
|
|
+ einfin( y );
|
|
|
+ if( *e & 0x8000 )
|
|
|
+ eneg(y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif /* INFINITY */
|
|
|
+yy[E] = r;
|
|
|
+p = &yy[M + 1];
|
|
|
+#ifdef IBMPC
|
|
|
+for( i=0; i<7; i++ )
|
|
|
+ *p++ = *(--e);
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+++e;
|
|
|
+for( i=0; i<7; i++ )
|
|
|
+ *p++ = *e++;
|
|
|
+#endif
|
|
|
+/* If denormal, remove the implied bit; else shift down 1. */
|
|
|
+if( r == 0 )
|
|
|
+ {
|
|
|
+ yy[M] = 0;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ yy[M] = 1;
|
|
|
+ eshift( yy, -1 );
|
|
|
+ }
|
|
|
+emovo(yy,y);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Convert IEEE single precision to e type
|
|
|
+; float d;
|
|
|
+; unsigned short x[N+2];
|
|
|
+; dtox( &d, x );
|
|
|
+*/
|
|
|
+void e24toe( pe, y )
|
|
|
+unsigned short *pe, *y;
|
|
|
+{
|
|
|
+register unsigned short r;
|
|
|
+register unsigned short *p, *e;
|
|
|
+unsigned short yy[NI];
|
|
|
+int denorm, k;
|
|
|
+
|
|
|
+e = pe;
|
|
|
+denorm = 0; /* flag if denormalized number */
|
|
|
+ecleaz(yy);
|
|
|
+#ifdef IBMPC
|
|
|
+e += 1;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+e += 1;
|
|
|
+#endif
|
|
|
+r = *e;
|
|
|
+yy[0] = 0;
|
|
|
+if( r & 0x8000 )
|
|
|
+ yy[0] = 0xffff;
|
|
|
+yy[M] = (r & 0x7f) | 0200;
|
|
|
+r &= ~0x807f; /* strip sign and 7 significand bits */
|
|
|
+#ifdef INFINITY
|
|
|
+if( r == 0x7f80 )
|
|
|
+ {
|
|
|
+#ifdef NANS
|
|
|
+#ifdef MIEEE
|
|
|
+ if( ((pe[0] & 0x7f) != 0) || (pe[1] != 0) )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#else
|
|
|
+ if( ((pe[1] & 0x7f) != 0) || (pe[0] != 0) )
|
|
|
+ {
|
|
|
+ enan( y, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#endif /* NANS */
|
|
|
+ eclear( y );
|
|
|
+ einfin( y );
|
|
|
+ if( yy[0] )
|
|
|
+ eneg(y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+r >>= 7;
|
|
|
+/* If zero exponent, then the significand is denormalized.
|
|
|
+ * So, take back the understood high significand bit. */
|
|
|
+if( r == 0 )
|
|
|
+ {
|
|
|
+ denorm = 1;
|
|
|
+ yy[M] &= ~0200;
|
|
|
+ }
|
|
|
+r += EXONE - 0177;
|
|
|
+yy[E] = r;
|
|
|
+p = &yy[M+1];
|
|
|
+#ifdef IBMPC
|
|
|
+*p++ = *(--e);
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+*p++ = *(--e);
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+++e;
|
|
|
+*p++ = *e++;
|
|
|
+#endif
|
|
|
+(void )eshift( yy, -8 );
|
|
|
+if( denorm )
|
|
|
+ { /* if zero exponent, then normalize the significand */
|
|
|
+ if( (k = enormlz(yy)) > NBITS )
|
|
|
+ ecleazs(yy);
|
|
|
+ else
|
|
|
+ yy[E] -= (unsigned short )(k-1);
|
|
|
+ }
|
|
|
+emovo( yy, y );
|
|
|
+}
|
|
|
+
|
|
|
+void etoe113(x,e)
|
|
|
+unsigned short *x, *e;
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+long exp;
|
|
|
+int rndsav;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(x) )
|
|
|
+ {
|
|
|
+ enan( e, 113 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( x, xi );
|
|
|
+exp = (long )xi[E];
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(x) )
|
|
|
+ goto nonorm;
|
|
|
+#endif
|
|
|
+/* round off to nearest or even */
|
|
|
+rndsav = rndprc;
|
|
|
+rndprc = 113;
|
|
|
+emdnorm( xi, 0, 0, exp, 64 );
|
|
|
+rndprc = rndsav;
|
|
|
+nonorm:
|
|
|
+toe113 (xi, e);
|
|
|
+}
|
|
|
+
|
|
|
+/* move out internal format to ieee long double */
|
|
|
+static void toe113(a,b)
|
|
|
+unsigned short *a, *b;
|
|
|
+{
|
|
|
+register unsigned short *p, *q;
|
|
|
+unsigned short i;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eiisnan(a) )
|
|
|
+ {
|
|
|
+ enan( b, 113 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+p = a;
|
|
|
+#ifdef MIEEE
|
|
|
+q = b;
|
|
|
+#else
|
|
|
+q = b + 7; /* point to output exponent */
|
|
|
+#endif
|
|
|
+
|
|
|
+/* If not denormal, delete the implied bit. */
|
|
|
+if( a[E] != 0 )
|
|
|
+ {
|
|
|
+ eshup1 (a);
|
|
|
+ }
|
|
|
+/* combine sign and exponent */
|
|
|
+i = *p++;
|
|
|
+#ifdef MIEEE
|
|
|
+if( i )
|
|
|
+ *q++ = *p++ | 0x8000;
|
|
|
+else
|
|
|
+ *q++ = *p++;
|
|
|
+#else
|
|
|
+if( i )
|
|
|
+ *q-- = *p++ | 0x8000;
|
|
|
+else
|
|
|
+ *q-- = *p++;
|
|
|
+#endif
|
|
|
+/* skip over guard word */
|
|
|
+++p;
|
|
|
+/* move the significand */
|
|
|
+#ifdef MIEEE
|
|
|
+for (i = 0; i < 7; i++)
|
|
|
+ *q++ = *p++;
|
|
|
+#else
|
|
|
+for (i = 0; i < 7; i++)
|
|
|
+ *q-- = *p++;
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+void etoe64( x, e )
|
|
|
+unsigned short *x, *e;
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+long exp;
|
|
|
+int rndsav;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(x) )
|
|
|
+ {
|
|
|
+ enan( e, 64 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( x, xi );
|
|
|
+exp = (long )xi[E]; /* adjust exponent for offset */
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(x) )
|
|
|
+ goto nonorm;
|
|
|
+#endif
|
|
|
+/* round off to nearest or even */
|
|
|
+rndsav = rndprc;
|
|
|
+rndprc = 64;
|
|
|
+emdnorm( xi, 0, 0, exp, 64 );
|
|
|
+rndprc = rndsav;
|
|
|
+nonorm:
|
|
|
+toe64( xi, e );
|
|
|
+}
|
|
|
+
|
|
|
+/* move out internal format to ieee long double */
|
|
|
+static void toe64( a, b )
|
|
|
+unsigned short *a, *b;
|
|
|
+{
|
|
|
+register unsigned short *p, *q;
|
|
|
+unsigned short i;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eiisnan(a) )
|
|
|
+ {
|
|
|
+ enan( b, 64 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+#ifdef IBMPC
|
|
|
+/* Shift Intel denormal significand down 1. */
|
|
|
+if( a[E] == 0 )
|
|
|
+ eshdn1(a);
|
|
|
+#endif
|
|
|
+p = a;
|
|
|
+#ifdef MIEEE
|
|
|
+q = b;
|
|
|
+#else
|
|
|
+q = b + 4; /* point to output exponent */
|
|
|
+#if 1
|
|
|
+/* NOTE: if data type is 96 bits wide, clear the last word here. */
|
|
|
+*(q+1)= 0;
|
|
|
+#endif
|
|
|
+#endif
|
|
|
+
|
|
|
+/* combine sign and exponent */
|
|
|
+i = *p++;
|
|
|
+#ifdef MIEEE
|
|
|
+if( i )
|
|
|
+ *q++ = *p++ | 0x8000;
|
|
|
+else
|
|
|
+ *q++ = *p++;
|
|
|
+*q++ = 0;
|
|
|
+#else
|
|
|
+if( i )
|
|
|
+ *q-- = *p++ | 0x8000;
|
|
|
+else
|
|
|
+ *q-- = *p++;
|
|
|
+#endif
|
|
|
+/* skip over guard word */
|
|
|
+++p;
|
|
|
+/* move the significand */
|
|
|
+#ifdef MIEEE
|
|
|
+for( i=0; i<4; i++ )
|
|
|
+ *q++ = *p++;
|
|
|
+#else
|
|
|
+#ifdef INFINITY
|
|
|
+if (eiisinf (a))
|
|
|
+ {
|
|
|
+ /* Intel long double infinity. */
|
|
|
+ *q-- = 0x8000;
|
|
|
+ *q-- = 0;
|
|
|
+ *q-- = 0;
|
|
|
+ *q = 0;
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+for( i=0; i<4; i++ )
|
|
|
+ *q-- = *p++;
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; e type to IEEE double precision
|
|
|
+; double d;
|
|
|
+; unsigned short x[NE];
|
|
|
+; etoe53( x, &d );
|
|
|
+*/
|
|
|
+
|
|
|
+#ifdef DEC
|
|
|
+
|
|
|
+void etoe53( x, e )
|
|
|
+unsigned short *x, *e;
|
|
|
+{
|
|
|
+etodec( x, e ); /* see etodec.c */
|
|
|
+}
|
|
|
+
|
|
|
+static void toe53( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+todec( x, y );
|
|
|
+}
|
|
|
+
|
|
|
+#else
|
|
|
+
|
|
|
+void etoe53( x, e )
|
|
|
+unsigned short *x, *e;
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+long exp;
|
|
|
+int rndsav;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(x) )
|
|
|
+ {
|
|
|
+ enan( e, 53 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( x, xi );
|
|
|
+exp = (long )xi[E] - (EXONE - 0x3ff); /* adjust exponent for offsets */
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(x) )
|
|
|
+ goto nonorm;
|
|
|
+#endif
|
|
|
+/* round off to nearest or even */
|
|
|
+rndsav = rndprc;
|
|
|
+rndprc = 53;
|
|
|
+emdnorm( xi, 0, 0, exp, 64 );
|
|
|
+rndprc = rndsav;
|
|
|
+nonorm:
|
|
|
+toe53( xi, e );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+static void toe53( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+unsigned short i;
|
|
|
+unsigned short *p;
|
|
|
+
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eiisnan(x) )
|
|
|
+ {
|
|
|
+ enan( y, 53 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+p = &x[0];
|
|
|
+#ifdef IBMPC
|
|
|
+y += 3;
|
|
|
+#endif
|
|
|
+*y = 0; /* output high order */
|
|
|
+if( *p++ )
|
|
|
+ *y = 0x8000; /* output sign bit */
|
|
|
+
|
|
|
+i = *p++;
|
|
|
+if( i >= (unsigned int )2047 )
|
|
|
+ { /* Saturate at largest number less than infinity. */
|
|
|
+#ifdef INFINITY
|
|
|
+ *y |= 0x7ff0;
|
|
|
+#ifdef IBMPC
|
|
|
+ *(--y) = 0;
|
|
|
+ *(--y) = 0;
|
|
|
+ *(--y) = 0;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+ ++y;
|
|
|
+ *y++ = 0;
|
|
|
+ *y++ = 0;
|
|
|
+ *y++ = 0;
|
|
|
+#endif
|
|
|
+#else
|
|
|
+ *y |= (unsigned short )0x7fef;
|
|
|
+#ifdef IBMPC
|
|
|
+ *(--y) = 0xffff;
|
|
|
+ *(--y) = 0xffff;
|
|
|
+ *(--y) = 0xffff;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+ ++y;
|
|
|
+ *y++ = 0xffff;
|
|
|
+ *y++ = 0xffff;
|
|
|
+ *y++ = 0xffff;
|
|
|
+#endif
|
|
|
+#endif
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( i == 0 )
|
|
|
+ {
|
|
|
+ (void )eshift( x, 4 );
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ i <<= 4;
|
|
|
+ (void )eshift( x, 5 );
|
|
|
+ }
|
|
|
+i |= *p++ & (unsigned short )0x0f; /* *p = xi[M] */
|
|
|
+*y |= (unsigned short )i; /* high order output already has sign bit set */
|
|
|
+#ifdef IBMPC
|
|
|
+*(--y) = *p++;
|
|
|
+*(--y) = *p++;
|
|
|
+*(--y) = *p;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+++y;
|
|
|
+*y++ = *p++;
|
|
|
+*y++ = *p++;
|
|
|
+*y++ = *p++;
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+#endif /* not DEC */
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; e type to IEEE single precision
|
|
|
+; float d;
|
|
|
+; unsigned short x[N+2];
|
|
|
+; xtod( x, &d );
|
|
|
+*/
|
|
|
+void etoe24( x, e )
|
|
|
+unsigned short *x, *e;
|
|
|
+{
|
|
|
+long exp;
|
|
|
+unsigned short xi[NI];
|
|
|
+int rndsav;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(x) )
|
|
|
+ {
|
|
|
+ enan( e, 24 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+emovi( x, xi );
|
|
|
+exp = (long )xi[E] - (EXONE - 0177); /* adjust exponent for offsets */
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(x) )
|
|
|
+ goto nonorm;
|
|
|
+#endif
|
|
|
+/* round off to nearest or even */
|
|
|
+rndsav = rndprc;
|
|
|
+rndprc = 24;
|
|
|
+emdnorm( xi, 0, 0, exp, 64 );
|
|
|
+rndprc = rndsav;
|
|
|
+nonorm:
|
|
|
+toe24( xi, e );
|
|
|
+}
|
|
|
+
|
|
|
+static void toe24( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+unsigned short i;
|
|
|
+unsigned short *p;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eiisnan(x) )
|
|
|
+ {
|
|
|
+ enan( y, 24 );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+p = &x[0];
|
|
|
+#ifdef IBMPC
|
|
|
+y += 1;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+y += 1;
|
|
|
+#endif
|
|
|
+*y = 0; /* output high order */
|
|
|
+if( *p++ )
|
|
|
+ *y = 0x8000; /* output sign bit */
|
|
|
+
|
|
|
+i = *p++;
|
|
|
+if( i >= 255 )
|
|
|
+ { /* Saturate at largest number less than infinity. */
|
|
|
+#ifdef INFINITY
|
|
|
+ *y |= (unsigned short )0x7f80;
|
|
|
+#ifdef IBMPC
|
|
|
+ *(--y) = 0;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+ *(--y) = 0;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+ ++y;
|
|
|
+ *y = 0;
|
|
|
+#endif
|
|
|
+#else
|
|
|
+ *y |= (unsigned short )0x7f7f;
|
|
|
+#ifdef IBMPC
|
|
|
+ *(--y) = 0xffff;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+ *(--y) = 0xffff;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+ ++y;
|
|
|
+ *y = 0xffff;
|
|
|
+#endif
|
|
|
+#endif
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( i == 0 )
|
|
|
+ {
|
|
|
+ (void )eshift( x, 7 );
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ i <<= 7;
|
|
|
+ (void )eshift( x, 8 );
|
|
|
+ }
|
|
|
+i |= *p++ & (unsigned short )0x7f; /* *p = xi[M] */
|
|
|
+*y |= i; /* high order output already has sign bit set */
|
|
|
+#ifdef IBMPC
|
|
|
+*(--y) = *p;
|
|
|
+#endif
|
|
|
+#ifdef DEC
|
|
|
+*(--y) = *p;
|
|
|
+#endif
|
|
|
+#ifdef MIEEE
|
|
|
+++y;
|
|
|
+*y = *p;
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* Compare two e type numbers.
|
|
|
+ *
|
|
|
+ * unsigned short a[NE], b[NE];
|
|
|
+ * ecmp( a, b );
|
|
|
+ *
|
|
|
+ * returns +1 if a > b
|
|
|
+ * 0 if a == b
|
|
|
+ * -1 if a < b
|
|
|
+ * -2 if either a or b is a NaN.
|
|
|
+ */
|
|
|
+int ecmp( a, b )
|
|
|
+unsigned short *a, *b;
|
|
|
+{
|
|
|
+unsigned short ai[NI], bi[NI];
|
|
|
+register unsigned short *p, *q;
|
|
|
+register int i;
|
|
|
+int msign;
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if (eisnan (a) || eisnan (b))
|
|
|
+ return( -2 );
|
|
|
+#endif
|
|
|
+emovi( a, ai );
|
|
|
+p = ai;
|
|
|
+emovi( b, bi );
|
|
|
+q = bi;
|
|
|
+
|
|
|
+if( *p != *q )
|
|
|
+ { /* the signs are different */
|
|
|
+/* -0 equals + 0 */
|
|
|
+ for( i=1; i<NI-1; i++ )
|
|
|
+ {
|
|
|
+ if( ai[i] != 0 )
|
|
|
+ goto nzro;
|
|
|
+ if( bi[i] != 0 )
|
|
|
+ goto nzro;
|
|
|
+ }
|
|
|
+ return(0);
|
|
|
+nzro:
|
|
|
+ if( *p == 0 )
|
|
|
+ return( 1 );
|
|
|
+ else
|
|
|
+ return( -1 );
|
|
|
+ }
|
|
|
+/* both are the same sign */
|
|
|
+if( *p == 0 )
|
|
|
+ msign = 1;
|
|
|
+else
|
|
|
+ msign = -1;
|
|
|
+i = NI-1;
|
|
|
+do
|
|
|
+ {
|
|
|
+ if( *p++ != *q++ )
|
|
|
+ {
|
|
|
+ goto diff;
|
|
|
+ }
|
|
|
+ }
|
|
|
+while( --i > 0 );
|
|
|
+
|
|
|
+return(0); /* equality */
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+diff:
|
|
|
+
|
|
|
+if( *(--p) > *(--q) )
|
|
|
+ return( msign ); /* p is bigger */
|
|
|
+else
|
|
|
+ return( -msign ); /* p is littler */
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Find nearest integer to x = floor( x + 0.5 )
|
|
|
+ *
|
|
|
+ * unsigned short x[NE], y[NE]
|
|
|
+ * eround( x, y );
|
|
|
+ */
|
|
|
+void eround( x, y )
|
|
|
+unsigned short *x, *y;
|
|
|
+{
|
|
|
+
|
|
|
+eadd( ehalf, x, y );
|
|
|
+efloor( y, y );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; convert long (32-bit) integer to e type
|
|
|
+;
|
|
|
+; long l;
|
|
|
+; unsigned short x[NE];
|
|
|
+; ltoe( &l, x );
|
|
|
+; note &l is the memory address of l
|
|
|
+*/
|
|
|
+void ltoe( lp, y )
|
|
|
+long *lp; /* lp is the memory address of a long integer */
|
|
|
+unsigned short *y; /* y is the address of a short */
|
|
|
+{
|
|
|
+unsigned short yi[NI];
|
|
|
+unsigned long ll;
|
|
|
+int k;
|
|
|
+
|
|
|
+ecleaz( yi );
|
|
|
+if( *lp < 0 )
|
|
|
+ {
|
|
|
+ ll = (unsigned long )( -(*lp) ); /* make it positive */
|
|
|
+ yi[0] = 0xffff; /* put correct sign in the e type number */
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ ll = (unsigned long )( *lp );
|
|
|
+ }
|
|
|
+/* move the long integer to yi significand area */
|
|
|
+if( sizeof(long) == 8 )
|
|
|
+ {
|
|
|
+ yi[M] = (unsigned short) (ll >> (LONGBITS - 16));
|
|
|
+ yi[M + 1] = (unsigned short) (ll >> (LONGBITS - 32));
|
|
|
+ yi[M + 2] = (unsigned short) (ll >> 16);
|
|
|
+ yi[M + 3] = (unsigned short) ll;
|
|
|
+ yi[E] = EXONE + 47; /* exponent if normalize shift count were 0 */
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ yi[M] = (unsigned short )(ll >> 16);
|
|
|
+ yi[M+1] = (unsigned short )ll;
|
|
|
+ yi[E] = EXONE + 15; /* exponent if normalize shift count were 0 */
|
|
|
+ }
|
|
|
+if( (k = enormlz( yi )) > NBITS ) /* normalize the significand */
|
|
|
+ ecleaz( yi ); /* it was zero */
|
|
|
+else
|
|
|
+ yi[E] -= (unsigned short )k; /* subtract shift count from exponent */
|
|
|
+emovo( yi, y ); /* output the answer */
|
|
|
+}
|
|
|
+
|
|
|
+/*
|
|
|
+; convert unsigned long (32-bit) integer to e type
|
|
|
+;
|
|
|
+; unsigned long l;
|
|
|
+; unsigned short x[NE];
|
|
|
+; ltox( &l, x );
|
|
|
+; note &l is the memory address of l
|
|
|
+*/
|
|
|
+void ultoe( lp, y )
|
|
|
+unsigned long *lp; /* lp is the memory address of a long integer */
|
|
|
+unsigned short *y; /* y is the address of a short */
|
|
|
+{
|
|
|
+unsigned short yi[NI];
|
|
|
+unsigned long ll;
|
|
|
+int k;
|
|
|
+
|
|
|
+ecleaz( yi );
|
|
|
+ll = *lp;
|
|
|
+
|
|
|
+/* move the long integer to ayi significand area */
|
|
|
+if( sizeof(long) == 8 )
|
|
|
+ {
|
|
|
+ yi[M] = (unsigned short) (ll >> (LONGBITS - 16));
|
|
|
+ yi[M + 1] = (unsigned short) (ll >> (LONGBITS - 32));
|
|
|
+ yi[M + 2] = (unsigned short) (ll >> 16);
|
|
|
+ yi[M + 3] = (unsigned short) ll;
|
|
|
+ yi[E] = EXONE + 47; /* exponent if normalize shift count were 0 */
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ yi[M] = (unsigned short )(ll >> 16);
|
|
|
+ yi[M+1] = (unsigned short )ll;
|
|
|
+ yi[E] = EXONE + 15; /* exponent if normalize shift count were 0 */
|
|
|
+ }
|
|
|
+if( (k = enormlz( yi )) > NBITS ) /* normalize the significand */
|
|
|
+ ecleaz( yi ); /* it was zero */
|
|
|
+else
|
|
|
+ yi[E] -= (unsigned short )k; /* subtract shift count from exponent */
|
|
|
+emovo( yi, y ); /* output the answer */
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Find long integer and fractional parts
|
|
|
+
|
|
|
+; long i;
|
|
|
+; unsigned short x[NE], frac[NE];
|
|
|
+; xifrac( x, &i, frac );
|
|
|
+
|
|
|
+ The integer output has the sign of the input. The fraction is
|
|
|
+ the positive fractional part of abs(x).
|
|
|
+*/
|
|
|
+void eifrac( x, i, frac )
|
|
|
+unsigned short *x;
|
|
|
+long *i;
|
|
|
+unsigned short *frac;
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+int j, k;
|
|
|
+unsigned long ll;
|
|
|
+
|
|
|
+emovi( x, xi );
|
|
|
+k = (int )xi[E] - (EXONE - 1);
|
|
|
+if( k <= 0 )
|
|
|
+ {
|
|
|
+/* if exponent <= 0, integer = 0 and real output is fraction */
|
|
|
+ *i = 0L;
|
|
|
+ emovo( xi, frac );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( k > (8 * sizeof(long) - 1) )
|
|
|
+ {
|
|
|
+/*
|
|
|
+; long integer overflow: output large integer
|
|
|
+; and correct fraction
|
|
|
+*/
|
|
|
+ j = 8 * sizeof(long) - 1;
|
|
|
+ if( xi[0] )
|
|
|
+ *i = (long) ((unsigned long) 1) << j;
|
|
|
+ else
|
|
|
+ *i = (long) (((unsigned long) (~(0L))) >> 1);
|
|
|
+ (void )eshift( xi, k );
|
|
|
+ }
|
|
|
+if( k > 16 )
|
|
|
+ {
|
|
|
+/*
|
|
|
+ Shift more than 16 bits: shift up k-16 mod 16
|
|
|
+ then shift by 16's.
|
|
|
+*/
|
|
|
+ j = k - ((k >> 4) << 4);
|
|
|
+ eshift (xi, j);
|
|
|
+ ll = xi[M];
|
|
|
+ k -= j;
|
|
|
+ do
|
|
|
+ {
|
|
|
+ eshup6 (xi);
|
|
|
+ ll = (ll << 16) | xi[M];
|
|
|
+ }
|
|
|
+ while ((k -= 16) > 0);
|
|
|
+ *i = ll;
|
|
|
+ if (xi[0])
|
|
|
+ *i = -(*i);
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+/* shift not more than 16 bits */
|
|
|
+ eshift( xi, k );
|
|
|
+ *i = (long )xi[M] & 0xffff;
|
|
|
+ if( xi[0] )
|
|
|
+ *i = -(*i);
|
|
|
+ }
|
|
|
+xi[0] = 0;
|
|
|
+xi[E] = EXONE - 1;
|
|
|
+xi[M] = 0;
|
|
|
+if( (k = enormlz( xi )) > NBITS )
|
|
|
+ ecleaz( xi );
|
|
|
+else
|
|
|
+ xi[E] -= (unsigned short )k;
|
|
|
+
|
|
|
+emovo( xi, frac );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Find unsigned long integer and fractional parts
|
|
|
+
|
|
|
+; unsigned long i;
|
|
|
+; unsigned short x[NE], frac[NE];
|
|
|
+; xifrac( x, &i, frac );
|
|
|
+
|
|
|
+ A negative e type input yields integer output = 0
|
|
|
+ but correct fraction.
|
|
|
+*/
|
|
|
+void euifrac( x, i, frac )
|
|
|
+unsigned short *x;
|
|
|
+unsigned long *i;
|
|
|
+unsigned short *frac;
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+int j, k;
|
|
|
+unsigned long ll;
|
|
|
+
|
|
|
+emovi( x, xi );
|
|
|
+k = (int )xi[E] - (EXONE - 1);
|
|
|
+if( k <= 0 )
|
|
|
+ {
|
|
|
+/* if exponent <= 0, integer = 0 and argument is fraction */
|
|
|
+ *i = 0L;
|
|
|
+ emovo( xi, frac );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+if( k > (8 * sizeof(long)) )
|
|
|
+ {
|
|
|
+/*
|
|
|
+; long integer overflow: output large integer
|
|
|
+; and correct fraction
|
|
|
+*/
|
|
|
+ *i = ~(0L);
|
|
|
+ (void )eshift( xi, k );
|
|
|
+ }
|
|
|
+else if( k > 16 )
|
|
|
+ {
|
|
|
+/*
|
|
|
+ Shift more than 16 bits: shift up k-16 mod 16
|
|
|
+ then shift up by 16's.
|
|
|
+*/
|
|
|
+ j = k - ((k >> 4) << 4);
|
|
|
+ eshift (xi, j);
|
|
|
+ ll = xi[M];
|
|
|
+ k -= j;
|
|
|
+ do
|
|
|
+ {
|
|
|
+ eshup6 (xi);
|
|
|
+ ll = (ll << 16) | xi[M];
|
|
|
+ }
|
|
|
+ while ((k -= 16) > 0);
|
|
|
+ *i = ll;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+/* shift not more than 16 bits */
|
|
|
+ eshift( xi, k );
|
|
|
+ *i = (long )xi[M] & 0xffff;
|
|
|
+ }
|
|
|
+
|
|
|
+if( xi[0] ) /* A negative value yields unsigned integer 0. */
|
|
|
+ *i = 0L;
|
|
|
+
|
|
|
+xi[0] = 0;
|
|
|
+xi[E] = EXONE - 1;
|
|
|
+xi[M] = 0;
|
|
|
+if( (k = enormlz( xi )) > NBITS )
|
|
|
+ ecleaz( xi );
|
|
|
+else
|
|
|
+ xi[E] -= (unsigned short )k;
|
|
|
+
|
|
|
+emovo( xi, frac );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; Shift significand
|
|
|
+;
|
|
|
+; Shifts significand area up or down by the number of bits
|
|
|
+; given by the variable sc.
|
|
|
+*/
|
|
|
+int eshift( x, sc )
|
|
|
+unsigned short *x;
|
|
|
+int sc;
|
|
|
+{
|
|
|
+unsigned short lost;
|
|
|
+unsigned short *p;
|
|
|
+
|
|
|
+if( sc == 0 )
|
|
|
+ return( 0 );
|
|
|
+
|
|
|
+lost = 0;
|
|
|
+p = x + NI-1;
|
|
|
+
|
|
|
+if( sc < 0 )
|
|
|
+ {
|
|
|
+ sc = -sc;
|
|
|
+ while( sc >= 16 )
|
|
|
+ {
|
|
|
+ lost |= *p; /* remember lost bits */
|
|
|
+ eshdn6(x);
|
|
|
+ sc -= 16;
|
|
|
+ }
|
|
|
+
|
|
|
+ while( sc >= 8 )
|
|
|
+ {
|
|
|
+ lost |= *p & 0xff;
|
|
|
+ eshdn8(x);
|
|
|
+ sc -= 8;
|
|
|
+ }
|
|
|
+
|
|
|
+ while( sc > 0 )
|
|
|
+ {
|
|
|
+ lost |= *p & 1;
|
|
|
+ eshdn1(x);
|
|
|
+ sc -= 1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ while( sc >= 16 )
|
|
|
+ {
|
|
|
+ eshup6(x);
|
|
|
+ sc -= 16;
|
|
|
+ }
|
|
|
+
|
|
|
+ while( sc >= 8 )
|
|
|
+ {
|
|
|
+ eshup8(x);
|
|
|
+ sc -= 8;
|
|
|
+ }
|
|
|
+
|
|
|
+ while( sc > 0 )
|
|
|
+ {
|
|
|
+ eshup1(x);
|
|
|
+ sc -= 1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+if( lost )
|
|
|
+ lost = 1;
|
|
|
+return( (int )lost );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; normalize
|
|
|
+;
|
|
|
+; Shift normalizes the significand area pointed to by argument
|
|
|
+; shift count (up = positive) is returned.
|
|
|
+*/
|
|
|
+int enormlz(x)
|
|
|
+unsigned short x[];
|
|
|
+{
|
|
|
+register unsigned short *p;
|
|
|
+int sc;
|
|
|
+
|
|
|
+sc = 0;
|
|
|
+p = &x[M];
|
|
|
+if( *p != 0 )
|
|
|
+ goto normdn;
|
|
|
+++p;
|
|
|
+if( *p & 0x8000 )
|
|
|
+ return( 0 ); /* already normalized */
|
|
|
+while( *p == 0 )
|
|
|
+ {
|
|
|
+ eshup6(x);
|
|
|
+ sc += 16;
|
|
|
+/* With guard word, there are NBITS+16 bits available.
|
|
|
+ * return true if all are zero.
|
|
|
+ */
|
|
|
+ if( sc > NBITS )
|
|
|
+ return( sc );
|
|
|
+ }
|
|
|
+/* see if high byte is zero */
|
|
|
+while( (*p & 0xff00) == 0 )
|
|
|
+ {
|
|
|
+ eshup8(x);
|
|
|
+ sc += 8;
|
|
|
+ }
|
|
|
+/* now shift 1 bit at a time */
|
|
|
+while( (*p & 0x8000) == 0)
|
|
|
+ {
|
|
|
+ eshup1(x);
|
|
|
+ sc += 1;
|
|
|
+ if( sc > (NBITS+16) )
|
|
|
+ {
|
|
|
+ mtherr( "enormlz", UNDERFLOW );
|
|
|
+ return( sc );
|
|
|
+ }
|
|
|
+ }
|
|
|
+return( sc );
|
|
|
+
|
|
|
+/* Normalize by shifting down out of the high guard word
|
|
|
+ of the significand */
|
|
|
+normdn:
|
|
|
+
|
|
|
+if( *p & 0xff00 )
|
|
|
+ {
|
|
|
+ eshdn8(x);
|
|
|
+ sc -= 8;
|
|
|
+ }
|
|
|
+while( *p != 0 )
|
|
|
+ {
|
|
|
+ eshdn1(x);
|
|
|
+ sc -= 1;
|
|
|
+
|
|
|
+ if( sc < -NBITS )
|
|
|
+ {
|
|
|
+ mtherr( "enormlz", OVERFLOW );
|
|
|
+ return( sc );
|
|
|
+ }
|
|
|
+ }
|
|
|
+return( sc );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Convert e type number to decimal format ASCII string.
|
|
|
+ * The constants are for 64 bit precision.
|
|
|
+ */
|
|
|
+
|
|
|
+#define NTEN 12
|
|
|
+#define MAXP 4096
|
|
|
+
|
|
|
+#if NE == 10
|
|
|
+static unsigned short etens[NTEN + 1][NE] =
|
|
|
+{
|
|
|
+ {0x6576, 0x4a92, 0x804a, 0x153f,
|
|
|
+ 0xc94c, 0x979a, 0x8a20, 0x5202, 0xc460, 0x7525,}, /* 10**4096 */
|
|
|
+ {0x6a32, 0xce52, 0x329a, 0x28ce,
|
|
|
+ 0xa74d, 0x5de4, 0xc53d, 0x3b5d, 0x9e8b, 0x5a92,}, /* 10**2048 */
|
|
|
+ {0x526c, 0x50ce, 0xf18b, 0x3d28,
|
|
|
+ 0x650d, 0x0c17, 0x8175, 0x7586, 0xc976, 0x4d48,},
|
|
|
+ {0x9c66, 0x58f8, 0xbc50, 0x5c54,
|
|
|
+ 0xcc65, 0x91c6, 0xa60e, 0xa0ae, 0xe319, 0x46a3,},
|
|
|
+ {0x851e, 0xeab7, 0x98fe, 0x901b,
|
|
|
+ 0xddbb, 0xde8d, 0x9df9, 0xebfb, 0xaa7e, 0x4351,},
|
|
|
+ {0x0235, 0x0137, 0x36b1, 0x336c,
|
|
|
+ 0xc66f, 0x8cdf, 0x80e9, 0x47c9, 0x93ba, 0x41a8,},
|
|
|
+ {0x50f8, 0x25fb, 0xc76b, 0x6b71,
|
|
|
+ 0x3cbf, 0xa6d5, 0xffcf, 0x1f49, 0xc278, 0x40d3,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0xf020, 0xb59d, 0x2b70, 0xada8, 0x9dc5, 0x4069,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0x0000, 0x0000, 0x0400, 0xc9bf, 0x8e1b, 0x4034,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0x0000, 0x0000, 0x0000, 0x2000, 0xbebc, 0x4019,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0x0000, 0x0000, 0x0000, 0x0000, 0x9c40, 0x400c,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0x0000, 0x0000, 0x0000, 0x0000, 0xc800, 0x4005,},
|
|
|
+ {0x0000, 0x0000, 0x0000, 0x0000,
|
|
|
+ 0x0000, 0x0000, 0x0000, 0x0000, 0xa000, 0x4002,}, /* 10**1 */
|
|
|
+};
|
|
|
+
|
|
|
+static unsigned short emtens[NTEN + 1][NE] =
|
|
|
+{
|
|
|
+ {0x2030, 0xcffc, 0xa1c3, 0x8123,
|
|
|
+ 0x2de3, 0x9fde, 0xd2ce, 0x04c8, 0xa6dd, 0x0ad8,}, /* 10**-4096 */
|
|
|
+ {0x8264, 0xd2cb, 0xf2ea, 0x12d4,
|
|
|
+ 0x4925, 0x2de4, 0x3436, 0x534f, 0xceae, 0x256b,}, /* 10**-2048 */
|
|
|
+ {0xf53f, 0xf698, 0x6bd3, 0x0158,
|
|
|
+ 0x87a6, 0xc0bd, 0xda57, 0x82a5, 0xa2a6, 0x32b5,},
|
|
|
+ {0xe731, 0x04d4, 0xe3f2, 0xd332,
|
|
|
+ 0x7132, 0xd21c, 0xdb23, 0xee32, 0x9049, 0x395a,},
|
|
|
+ {0xa23e, 0x5308, 0xfefb, 0x1155,
|
|
|
+ 0xfa91, 0x1939, 0x637a, 0x4325, 0xc031, 0x3cac,},
|
|
|
+ {0xe26d, 0xdbde, 0xd05d, 0xb3f6,
|
|
|
+ 0xac7c, 0xe4a0, 0x64bc, 0x467c, 0xddd0, 0x3e55,},
|
|
|
+ {0x2a20, 0x6224, 0x47b3, 0x98d7,
|
|
|
+ 0x3f23, 0xe9a5, 0xa539, 0xea27, 0xa87f, 0x3f2a,},
|
|
|
+ {0x0b5b, 0x4af2, 0xa581, 0x18ed,
|
|
|
+ 0x67de, 0x94ba, 0x4539, 0x1ead, 0xcfb1, 0x3f94,},
|
|
|
+ {0xbf71, 0xa9b3, 0x7989, 0xbe68,
|
|
|
+ 0x4c2e, 0xe15b, 0xc44d, 0x94be, 0xe695, 0x3fc9,},
|
|
|
+ {0x3d4d, 0x7c3d, 0x36ba, 0x0d2b,
|
|
|
+ 0xfdc2, 0xcefc, 0x8461, 0x7711, 0xabcc, 0x3fe4,},
|
|
|
+ {0xc155, 0xa4a8, 0x404e, 0x6113,
|
|
|
+ 0xd3c3, 0x652b, 0xe219, 0x1758, 0xd1b7, 0x3ff1,},
|
|
|
+ {0xd70a, 0x70a3, 0x0a3d, 0xa3d7,
|
|
|
+ 0x3d70, 0xd70a, 0x70a3, 0x0a3d, 0xa3d7, 0x3ff8,},
|
|
|
+ {0xcccd, 0xcccc, 0xcccc, 0xcccc,
|
|
|
+ 0xcccc, 0xcccc, 0xcccc, 0xcccc, 0xcccc, 0x3ffb,}, /* 10**-1 */
|
|
|
+};
|
|
|
+#else
|
|
|
+static unsigned short etens[NTEN+1][NE] = {
|
|
|
+{0xc94c,0x979a,0x8a20,0x5202,0xc460,0x7525,},/* 10**4096 */
|
|
|
+{0xa74d,0x5de4,0xc53d,0x3b5d,0x9e8b,0x5a92,},/* 10**2048 */
|
|
|
+{0x650d,0x0c17,0x8175,0x7586,0xc976,0x4d48,},
|
|
|
+{0xcc65,0x91c6,0xa60e,0xa0ae,0xe319,0x46a3,},
|
|
|
+{0xddbc,0xde8d,0x9df9,0xebfb,0xaa7e,0x4351,},
|
|
|
+{0xc66f,0x8cdf,0x80e9,0x47c9,0x93ba,0x41a8,},
|
|
|
+{0x3cbf,0xa6d5,0xffcf,0x1f49,0xc278,0x40d3,},
|
|
|
+{0xf020,0xb59d,0x2b70,0xada8,0x9dc5,0x4069,},
|
|
|
+{0x0000,0x0000,0x0400,0xc9bf,0x8e1b,0x4034,},
|
|
|
+{0x0000,0x0000,0x0000,0x2000,0xbebc,0x4019,},
|
|
|
+{0x0000,0x0000,0x0000,0x0000,0x9c40,0x400c,},
|
|
|
+{0x0000,0x0000,0x0000,0x0000,0xc800,0x4005,},
|
|
|
+{0x0000,0x0000,0x0000,0x0000,0xa000,0x4002,}, /* 10**1 */
|
|
|
+};
|
|
|
+
|
|
|
+static unsigned short emtens[NTEN+1][NE] = {
|
|
|
+{0x2de4,0x9fde,0xd2ce,0x04c8,0xa6dd,0x0ad8,}, /* 10**-4096 */
|
|
|
+{0x4925,0x2de4,0x3436,0x534f,0xceae,0x256b,}, /* 10**-2048 */
|
|
|
+{0x87a6,0xc0bd,0xda57,0x82a5,0xa2a6,0x32b5,},
|
|
|
+{0x7133,0xd21c,0xdb23,0xee32,0x9049,0x395a,},
|
|
|
+{0xfa91,0x1939,0x637a,0x4325,0xc031,0x3cac,},
|
|
|
+{0xac7d,0xe4a0,0x64bc,0x467c,0xddd0,0x3e55,},
|
|
|
+{0x3f24,0xe9a5,0xa539,0xea27,0xa87f,0x3f2a,},
|
|
|
+{0x67de,0x94ba,0x4539,0x1ead,0xcfb1,0x3f94,},
|
|
|
+{0x4c2f,0xe15b,0xc44d,0x94be,0xe695,0x3fc9,},
|
|
|
+{0xfdc2,0xcefc,0x8461,0x7711,0xabcc,0x3fe4,},
|
|
|
+{0xd3c3,0x652b,0xe219,0x1758,0xd1b7,0x3ff1,},
|
|
|
+{0x3d71,0xd70a,0x70a3,0x0a3d,0xa3d7,0x3ff8,},
|
|
|
+{0xcccd,0xcccc,0xcccc,0xcccc,0xcccc,0x3ffb,}, /* 10**-1 */
|
|
|
+};
|
|
|
+#endif
|
|
|
+
|
|
|
+void e24toasc( x, string, ndigs )
|
|
|
+unsigned short x[];
|
|
|
+char *string;
|
|
|
+int ndigs;
|
|
|
+{
|
|
|
+unsigned short w[NI];
|
|
|
+
|
|
|
+e24toe( x, w );
|
|
|
+etoasc( w, string, ndigs );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+void e53toasc( x, string, ndigs )
|
|
|
+unsigned short x[];
|
|
|
+char *string;
|
|
|
+int ndigs;
|
|
|
+{
|
|
|
+unsigned short w[NI];
|
|
|
+
|
|
|
+e53toe( x, w );
|
|
|
+etoasc( w, string, ndigs );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+void e64toasc( x, string, ndigs )
|
|
|
+unsigned short x[];
|
|
|
+char *string;
|
|
|
+int ndigs;
|
|
|
+{
|
|
|
+unsigned short w[NI];
|
|
|
+
|
|
|
+e64toe( x, w );
|
|
|
+etoasc( w, string, ndigs );
|
|
|
+}
|
|
|
+
|
|
|
+void e113toasc (x, string, ndigs)
|
|
|
+unsigned short x[];
|
|
|
+char *string;
|
|
|
+int ndigs;
|
|
|
+{
|
|
|
+unsigned short w[NI];
|
|
|
+
|
|
|
+e113toe (x, w);
|
|
|
+etoasc (w, string, ndigs);
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+void etoasc( x, string, ndigs )
|
|
|
+unsigned short x[];
|
|
|
+char *string;
|
|
|
+int ndigs;
|
|
|
+{
|
|
|
+long digit;
|
|
|
+unsigned short y[NI], t[NI], u[NI], w[NI];
|
|
|
+unsigned short *p, *r, *ten;
|
|
|
+unsigned short sign;
|
|
|
+int i, j, k, expon, rndsav;
|
|
|
+char *s, *ss;
|
|
|
+unsigned short m;
|
|
|
+
|
|
|
+rndsav = rndprc;
|
|
|
+#ifdef NANS
|
|
|
+if( eisnan(x) )
|
|
|
+ {
|
|
|
+ sprintf( string, " NaN " );
|
|
|
+ goto bxit;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+rndprc = NBITS; /* set to full precision */
|
|
|
+emov( x, y ); /* retain external format */
|
|
|
+if( y[NE-1] & 0x8000 )
|
|
|
+ {
|
|
|
+ sign = 0xffff;
|
|
|
+ y[NE-1] &= 0x7fff;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ sign = 0;
|
|
|
+ }
|
|
|
+expon = 0;
|
|
|
+ten = &etens[NTEN][0];
|
|
|
+emov( eone, t );
|
|
|
+/* Test for zero exponent */
|
|
|
+if( y[NE-1] == 0 )
|
|
|
+ {
|
|
|
+ for( k=0; k<NE-1; k++ )
|
|
|
+ {
|
|
|
+ if( y[k] != 0 )
|
|
|
+ goto tnzro; /* denormalized number */
|
|
|
+ }
|
|
|
+ goto isone; /* legal all zeros */
|
|
|
+ }
|
|
|
+tnzro:
|
|
|
+
|
|
|
+/* Test for infinity.
|
|
|
+ */
|
|
|
+if( y[NE-1] == 0x7fff )
|
|
|
+ {
|
|
|
+ if( sign )
|
|
|
+ sprintf( string, " -Infinity " );
|
|
|
+ else
|
|
|
+ sprintf( string, " Infinity " );
|
|
|
+ goto bxit;
|
|
|
+ }
|
|
|
+
|
|
|
+/* Test for exponent nonzero but significand denormalized.
|
|
|
+ * This is an error condition.
|
|
|
+ */
|
|
|
+if( (y[NE-1] != 0) && ((y[NE-2] & 0x8000) == 0) )
|
|
|
+ {
|
|
|
+ mtherr( "etoasc", DOMAIN );
|
|
|
+ sprintf( string, "NaN" );
|
|
|
+ goto bxit;
|
|
|
+ }
|
|
|
+
|
|
|
+/* Compare to 1.0 */
|
|
|
+i = ecmp( eone, y );
|
|
|
+if( i == 0 )
|
|
|
+ goto isone;
|
|
|
+
|
|
|
+if( i < 0 )
|
|
|
+ { /* Number is greater than 1 */
|
|
|
+/* Convert significand to an integer and strip trailing decimal zeros. */
|
|
|
+ emov( y, u );
|
|
|
+ u[NE-1] = EXONE + NBITS - 1;
|
|
|
+
|
|
|
+ p = &etens[NTEN-4][0];
|
|
|
+ m = 16;
|
|
|
+do
|
|
|
+ {
|
|
|
+ ediv( p, u, t );
|
|
|
+ efloor( t, w );
|
|
|
+ for( j=0; j<NE-1; j++ )
|
|
|
+ {
|
|
|
+ if( t[j] != w[j] )
|
|
|
+ goto noint;
|
|
|
+ }
|
|
|
+ emov( t, u );
|
|
|
+ expon += (int )m;
|
|
|
+noint:
|
|
|
+ p += NE;
|
|
|
+ m >>= 1;
|
|
|
+ }
|
|
|
+while( m != 0 );
|
|
|
+
|
|
|
+/* Rescale from integer significand */
|
|
|
+ u[NE-1] += y[NE-1] - (unsigned int )(EXONE + NBITS - 1);
|
|
|
+ emov( u, y );
|
|
|
+/* Find power of 10 */
|
|
|
+ emov( eone, t );
|
|
|
+ m = MAXP;
|
|
|
+ p = &etens[0][0];
|
|
|
+ while( ecmp( ten, u ) <= 0 )
|
|
|
+ {
|
|
|
+ if( ecmp( p, u ) <= 0 )
|
|
|
+ {
|
|
|
+ ediv( p, u, u );
|
|
|
+ emul( p, t, t );
|
|
|
+ expon += (int )m;
|
|
|
+ }
|
|
|
+ m >>= 1;
|
|
|
+ if( m == 0 )
|
|
|
+ break;
|
|
|
+ p += NE;
|
|
|
+ }
|
|
|
+ }
|
|
|
+else
|
|
|
+ { /* Number is less than 1.0 */
|
|
|
+/* Pad significand with trailing decimal zeros. */
|
|
|
+ if( y[NE-1] == 0 )
|
|
|
+ {
|
|
|
+ while( (y[NE-2] & 0x8000) == 0 )
|
|
|
+ {
|
|
|
+ emul( ten, y, y );
|
|
|
+ expon -= 1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ emovi( y, w );
|
|
|
+ for( i=0; i<NDEC+1; i++ )
|
|
|
+ {
|
|
|
+ if( (w[NI-1] & 0x7) != 0 )
|
|
|
+ break;
|
|
|
+/* multiply by 10 */
|
|
|
+ emovz( w, u );
|
|
|
+ eshdn1( u );
|
|
|
+ eshdn1( u );
|
|
|
+ eaddm( w, u );
|
|
|
+ u[1] += 3;
|
|
|
+ while( u[2] != 0 )
|
|
|
+ {
|
|
|
+ eshdn1(u);
|
|
|
+ u[1] += 1;
|
|
|
+ }
|
|
|
+ if( u[NI-1] != 0 )
|
|
|
+ break;
|
|
|
+ if( eone[NE-1] <= u[1] )
|
|
|
+ break;
|
|
|
+ emovz( u, w );
|
|
|
+ expon -= 1;
|
|
|
+ }
|
|
|
+ emovo( w, y );
|
|
|
+ }
|
|
|
+ k = -MAXP;
|
|
|
+ p = &emtens[0][0];
|
|
|
+ r = &etens[0][0];
|
|
|
+ emov( y, w );
|
|
|
+ emov( eone, t );
|
|
|
+ while( ecmp( eone, w ) > 0 )
|
|
|
+ {
|
|
|
+ if( ecmp( p, w ) >= 0 )
|
|
|
+ {
|
|
|
+ emul( r, w, w );
|
|
|
+ emul( r, t, t );
|
|
|
+ expon += k;
|
|
|
+ }
|
|
|
+ k /= 2;
|
|
|
+ if( k == 0 )
|
|
|
+ break;
|
|
|
+ p += NE;
|
|
|
+ r += NE;
|
|
|
+ }
|
|
|
+ ediv( t, eone, t );
|
|
|
+ }
|
|
|
+isone:
|
|
|
+/* Find the first (leading) digit. */
|
|
|
+emovi( t, w );
|
|
|
+emovz( w, t );
|
|
|
+emovi( y, w );
|
|
|
+emovz( w, y );
|
|
|
+eiremain( t, y );
|
|
|
+digit = equot[NI-1];
|
|
|
+while( (digit == 0) && (ecmp(y,ezero) != 0) )
|
|
|
+ {
|
|
|
+ eshup1( y );
|
|
|
+ emovz( y, u );
|
|
|
+ eshup1( u );
|
|
|
+ eshup1( u );
|
|
|
+ eaddm( u, y );
|
|
|
+ eiremain( t, y );
|
|
|
+ digit = equot[NI-1];
|
|
|
+ expon -= 1;
|
|
|
+ }
|
|
|
+s = string;
|
|
|
+if( sign )
|
|
|
+ *s++ = '-';
|
|
|
+else
|
|
|
+ *s++ = ' ';
|
|
|
+/* Examine number of digits requested by caller. */
|
|
|
+if( ndigs < 0 )
|
|
|
+ ndigs = 0;
|
|
|
+if( ndigs > NDEC )
|
|
|
+ ndigs = NDEC;
|
|
|
+if( digit == 10 )
|
|
|
+ {
|
|
|
+ *s++ = '1';
|
|
|
+ *s++ = '.';
|
|
|
+ if( ndigs > 0 )
|
|
|
+ {
|
|
|
+ *s++ = '0';
|
|
|
+ ndigs -= 1;
|
|
|
+ }
|
|
|
+ expon += 1;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ *s++ = (char )digit + '0';
|
|
|
+ *s++ = '.';
|
|
|
+ }
|
|
|
+/* Generate digits after the decimal point. */
|
|
|
+for( k=0; k<=ndigs; k++ )
|
|
|
+ {
|
|
|
+/* multiply current number by 10, without normalizing */
|
|
|
+ eshup1( y );
|
|
|
+ emovz( y, u );
|
|
|
+ eshup1( u );
|
|
|
+ eshup1( u );
|
|
|
+ eaddm( u, y );
|
|
|
+ eiremain( t, y );
|
|
|
+ *s++ = (char )equot[NI-1] + '0';
|
|
|
+ }
|
|
|
+digit = equot[NI-1];
|
|
|
+--s;
|
|
|
+ss = s;
|
|
|
+/* round off the ASCII string */
|
|
|
+if( digit > 4 )
|
|
|
+ {
|
|
|
+/* Test for critical rounding case in ASCII output. */
|
|
|
+ if( digit == 5 )
|
|
|
+ {
|
|
|
+ emovo( y, t );
|
|
|
+ if( ecmp(t,ezero) != 0 )
|
|
|
+ goto roun; /* round to nearest */
|
|
|
+ if( (*(s-1) & 1) == 0 )
|
|
|
+ goto doexp; /* round to even */
|
|
|
+ }
|
|
|
+/* Round up and propagate carry-outs */
|
|
|
+roun:
|
|
|
+ --s;
|
|
|
+ k = *s & 0x7f;
|
|
|
+/* Carry out to most significant digit? */
|
|
|
+ if( k == '.' )
|
|
|
+ {
|
|
|
+ --s;
|
|
|
+ k = *s;
|
|
|
+ k += 1;
|
|
|
+ *s = (char )k;
|
|
|
+/* Most significant digit carries to 10? */
|
|
|
+ if( k > '9' )
|
|
|
+ {
|
|
|
+ expon += 1;
|
|
|
+ *s = '1';
|
|
|
+ }
|
|
|
+ goto doexp;
|
|
|
+ }
|
|
|
+/* Round up and carry out from less significant digits */
|
|
|
+ k += 1;
|
|
|
+ *s = (char )k;
|
|
|
+ if( k > '9' )
|
|
|
+ {
|
|
|
+ *s = '0';
|
|
|
+ goto roun;
|
|
|
+ }
|
|
|
+ }
|
|
|
+doexp:
|
|
|
+/*
|
|
|
+if( expon >= 0 )
|
|
|
+ sprintf( ss, "e+%d", expon );
|
|
|
+else
|
|
|
+ sprintf( ss, "e%d", expon );
|
|
|
+*/
|
|
|
+ sprintf( ss, "E%d", expon );
|
|
|
+bxit:
|
|
|
+rndprc = rndsav;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/*
|
|
|
+; ASCTOQ
|
|
|
+; ASCTOQ.MAC LATEST REV: 11 JAN 84
|
|
|
+; SLM, 3 JAN 78
|
|
|
+;
|
|
|
+; Convert ASCII string to quadruple precision floating point
|
|
|
+;
|
|
|
+; Numeric input is free field decimal number
|
|
|
+; with max of 15 digits with or without
|
|
|
+; decimal point entered as ASCII from teletype.
|
|
|
+; Entering E after the number followed by a second
|
|
|
+; number causes the second number to be interpreted
|
|
|
+; as a power of 10 to be multiplied by the first number
|
|
|
+; (i.e., "scientific" notation).
|
|
|
+;
|
|
|
+; Usage:
|
|
|
+; asctoq( string, q );
|
|
|
+*/
|
|
|
+
|
|
|
+/* ASCII to single */
|
|
|
+void asctoe24( s, y )
|
|
|
+char *s;
|
|
|
+unsigned short *y;
|
|
|
+{
|
|
|
+asctoeg( s, y, 24 );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* ASCII to double */
|
|
|
+void asctoe53( s, y )
|
|
|
+char *s;
|
|
|
+unsigned short *y;
|
|
|
+{
|
|
|
+#ifdef DEC
|
|
|
+asctoeg( s, y, 56 );
|
|
|
+#else
|
|
|
+asctoeg( s, y, 53 );
|
|
|
+#endif
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* ASCII to long double */
|
|
|
+void asctoe64( s, y )
|
|
|
+char *s;
|
|
|
+unsigned short *y;
|
|
|
+{
|
|
|
+asctoeg( s, y, 64 );
|
|
|
+}
|
|
|
+
|
|
|
+/* ASCII to 128-bit long double */
|
|
|
+void asctoe113 (s, y)
|
|
|
+char *s;
|
|
|
+unsigned short *y;
|
|
|
+{
|
|
|
+asctoeg( s, y, 113 );
|
|
|
+}
|
|
|
+
|
|
|
+/* ASCII to super double */
|
|
|
+void asctoe( s, y )
|
|
|
+char *s;
|
|
|
+unsigned short *y;
|
|
|
+{
|
|
|
+asctoeg( s, y, NBITS );
|
|
|
+}
|
|
|
+
|
|
|
+/* Space to make a copy of the input string: */
|
|
|
+static char lstr[82] = {0};
|
|
|
+
|
|
|
+void asctoeg( ss, y, oprec )
|
|
|
+char *ss;
|
|
|
+unsigned short *y;
|
|
|
+int oprec;
|
|
|
+{
|
|
|
+unsigned short yy[NI], xt[NI], tt[NI];
|
|
|
+int esign, decflg, sgnflg, nexp, exp, prec, lost;
|
|
|
+int k, trail, c, rndsav;
|
|
|
+long lexp;
|
|
|
+unsigned short nsign, *p;
|
|
|
+char *sp, *s;
|
|
|
+
|
|
|
+/* Copy the input string. */
|
|
|
+s = ss;
|
|
|
+while( *s == ' ' ) /* skip leading spaces */
|
|
|
+ ++s;
|
|
|
+sp = lstr;
|
|
|
+for( k=0; k<79; k++ )
|
|
|
+ {
|
|
|
+ if( (*sp++ = *s++) == '\0' )
|
|
|
+ break;
|
|
|
+ }
|
|
|
+*sp = '\0';
|
|
|
+s = lstr;
|
|
|
+
|
|
|
+rndsav = rndprc;
|
|
|
+rndprc = NBITS; /* Set to full precision */
|
|
|
+lost = 0;
|
|
|
+nsign = 0;
|
|
|
+decflg = 0;
|
|
|
+sgnflg = 0;
|
|
|
+nexp = 0;
|
|
|
+exp = 0;
|
|
|
+prec = 0;
|
|
|
+ecleaz( yy );
|
|
|
+trail = 0;
|
|
|
+
|
|
|
+nxtcom:
|
|
|
+k = *s - '0';
|
|
|
+if( (k >= 0) && (k <= 9) )
|
|
|
+ {
|
|
|
+/* Ignore leading zeros */
|
|
|
+ if( (prec == 0) && (decflg == 0) && (k == 0) )
|
|
|
+ goto donchr;
|
|
|
+/* Identify and strip trailing zeros after the decimal point. */
|
|
|
+ if( (trail == 0) && (decflg != 0) )
|
|
|
+ {
|
|
|
+ sp = s;
|
|
|
+ while( (*sp >= '0') && (*sp <= '9') )
|
|
|
+ ++sp;
|
|
|
+/* Check for syntax error */
|
|
|
+ c = *sp & 0x7f;
|
|
|
+ if( (c != 'e') && (c != 'E') && (c != '\0')
|
|
|
+ && (c != '\n') && (c != '\r') && (c != ' ')
|
|
|
+ && (c != ',') )
|
|
|
+ goto error;
|
|
|
+ --sp;
|
|
|
+ while( *sp == '0' )
|
|
|
+ *sp-- = 'z';
|
|
|
+ trail = 1;
|
|
|
+ if( *s == 'z' )
|
|
|
+ goto donchr;
|
|
|
+ }
|
|
|
+/* If enough digits were given to more than fill up the yy register,
|
|
|
+ * continuing until overflow into the high guard word yy[2]
|
|
|
+ * guarantees that there will be a roundoff bit at the top
|
|
|
+ * of the low guard word after normalization.
|
|
|
+ */
|
|
|
+ if( yy[2] == 0 )
|
|
|
+ {
|
|
|
+ if( decflg )
|
|
|
+ nexp += 1; /* count digits after decimal point */
|
|
|
+ eshup1( yy ); /* multiply current number by 10 */
|
|
|
+ emovz( yy, xt );
|
|
|
+ eshup1( xt );
|
|
|
+ eshup1( xt );
|
|
|
+ eaddm( xt, yy );
|
|
|
+ ecleaz( xt );
|
|
|
+ xt[NI-2] = (unsigned short )k;
|
|
|
+ eaddm( xt, yy );
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ /* Mark any lost non-zero digit. */
|
|
|
+ lost |= k;
|
|
|
+ /* Count lost digits before the decimal point. */
|
|
|
+ if (decflg == 0)
|
|
|
+ nexp -= 1;
|
|
|
+ }
|
|
|
+ prec += 1;
|
|
|
+ goto donchr;
|
|
|
+ }
|
|
|
+
|
|
|
+switch( *s )
|
|
|
+ {
|
|
|
+ case 'z':
|
|
|
+ break;
|
|
|
+ case 'E':
|
|
|
+ case 'e':
|
|
|
+ goto expnt;
|
|
|
+ case '.': /* decimal point */
|
|
|
+ if( decflg )
|
|
|
+ goto error;
|
|
|
+ ++decflg;
|
|
|
+ break;
|
|
|
+ case '-':
|
|
|
+ nsign = 0xffff;
|
|
|
+ if( sgnflg )
|
|
|
+ goto error;
|
|
|
+ ++sgnflg;
|
|
|
+ break;
|
|
|
+ case '+':
|
|
|
+ if( sgnflg )
|
|
|
+ goto error;
|
|
|
+ ++sgnflg;
|
|
|
+ break;
|
|
|
+ case ',':
|
|
|
+ case ' ':
|
|
|
+ case '\0':
|
|
|
+ case '\n':
|
|
|
+ case '\r':
|
|
|
+ goto daldone;
|
|
|
+ case 'i':
|
|
|
+ case 'I':
|
|
|
+ goto infinite;
|
|
|
+ default:
|
|
|
+ error:
|
|
|
+#ifdef NANS
|
|
|
+ enan( yy, NI*16 );
|
|
|
+#else
|
|
|
+ mtherr( "asctoe", DOMAIN );
|
|
|
+ ecleaz(yy);
|
|
|
+#endif
|
|
|
+ goto aexit;
|
|
|
+ }
|
|
|
+donchr:
|
|
|
+++s;
|
|
|
+goto nxtcom;
|
|
|
+
|
|
|
+/* Exponent interpretation */
|
|
|
+expnt:
|
|
|
+
|
|
|
+esign = 1;
|
|
|
+exp = 0;
|
|
|
+++s;
|
|
|
+/* check for + or - */
|
|
|
+if( *s == '-' )
|
|
|
+ {
|
|
|
+ esign = -1;
|
|
|
+ ++s;
|
|
|
+ }
|
|
|
+if( *s == '+' )
|
|
|
+ ++s;
|
|
|
+while( (*s >= '0') && (*s <= '9') )
|
|
|
+ {
|
|
|
+ exp *= 10;
|
|
|
+ exp += *s++ - '0';
|
|
|
+ if (exp > 4977)
|
|
|
+ {
|
|
|
+ if (esign < 0)
|
|
|
+ goto zero;
|
|
|
+ else
|
|
|
+ goto infinite;
|
|
|
+ }
|
|
|
+ }
|
|
|
+if( esign < 0 )
|
|
|
+ exp = -exp;
|
|
|
+if( exp > 4932 )
|
|
|
+ {
|
|
|
+infinite:
|
|
|
+ ecleaz(yy);
|
|
|
+ yy[E] = 0x7fff; /* infinity */
|
|
|
+ goto aexit;
|
|
|
+ }
|
|
|
+if( exp < -4977 )
|
|
|
+ {
|
|
|
+zero:
|
|
|
+ ecleaz(yy);
|
|
|
+ goto aexit;
|
|
|
+ }
|
|
|
+
|
|
|
+daldone:
|
|
|
+nexp = exp - nexp;
|
|
|
+/* Pad trailing zeros to minimize power of 10, per IEEE spec. */
|
|
|
+while( (nexp > 0) && (yy[2] == 0) )
|
|
|
+ {
|
|
|
+ emovz( yy, xt );
|
|
|
+ eshup1( xt );
|
|
|
+ eshup1( xt );
|
|
|
+ eaddm( yy, xt );
|
|
|
+ eshup1( xt );
|
|
|
+ if( xt[2] != 0 )
|
|
|
+ break;
|
|
|
+ nexp -= 1;
|
|
|
+ emovz( xt, yy );
|
|
|
+ }
|
|
|
+if( (k = enormlz(yy)) > NBITS )
|
|
|
+ {
|
|
|
+ ecleaz(yy);
|
|
|
+ goto aexit;
|
|
|
+ }
|
|
|
+lexp = (EXONE - 1 + NBITS) - k;
|
|
|
+emdnorm( yy, lost, 0, lexp, 64 );
|
|
|
+/* convert to external format */
|
|
|
+
|
|
|
+
|
|
|
+/* Multiply by 10**nexp. If precision is 64 bits,
|
|
|
+ * the maximum relative error incurred in forming 10**n
|
|
|
+ * for 0 <= n <= 324 is 8.2e-20, at 10**180.
|
|
|
+ * For 0 <= n <= 999, the peak relative error is 1.4e-19 at 10**947.
|
|
|
+ * For 0 >= n >= -999, it is -1.55e-19 at 10**-435.
|
|
|
+ */
|
|
|
+lexp = yy[E];
|
|
|
+if( nexp == 0 )
|
|
|
+ {
|
|
|
+ k = 0;
|
|
|
+ goto expdon;
|
|
|
+ }
|
|
|
+esign = 1;
|
|
|
+if( nexp < 0 )
|
|
|
+ {
|
|
|
+ nexp = -nexp;
|
|
|
+ esign = -1;
|
|
|
+ if( nexp > 4096 )
|
|
|
+ { /* Punt. Can't handle this without 2 divides. */
|
|
|
+ emovi( etens[0], tt );
|
|
|
+ lexp -= tt[E];
|
|
|
+ k = edivm( tt, yy );
|
|
|
+ lexp += EXONE;
|
|
|
+ nexp -= 4096;
|
|
|
+ }
|
|
|
+ }
|
|
|
+p = &etens[NTEN][0];
|
|
|
+emov( eone, xt );
|
|
|
+exp = 1;
|
|
|
+do
|
|
|
+ {
|
|
|
+ if( exp & nexp )
|
|
|
+ emul( p, xt, xt );
|
|
|
+ p -= NE;
|
|
|
+ exp = exp + exp;
|
|
|
+ }
|
|
|
+while( exp <= MAXP );
|
|
|
+
|
|
|
+emovi( xt, tt );
|
|
|
+if( esign < 0 )
|
|
|
+ {
|
|
|
+ lexp -= tt[E];
|
|
|
+ k = edivm( tt, yy );
|
|
|
+ lexp += EXONE;
|
|
|
+ }
|
|
|
+else
|
|
|
+ {
|
|
|
+ lexp += tt[E];
|
|
|
+ k = emulm( tt, yy );
|
|
|
+ lexp -= EXONE - 1;
|
|
|
+ }
|
|
|
+
|
|
|
+expdon:
|
|
|
+
|
|
|
+/* Round and convert directly to the destination type */
|
|
|
+if( oprec == 53 )
|
|
|
+ lexp -= EXONE - 0x3ff;
|
|
|
+else if( oprec == 24 )
|
|
|
+ lexp -= EXONE - 0177;
|
|
|
+#ifdef DEC
|
|
|
+else if( oprec == 56 )
|
|
|
+ lexp -= EXONE - 0201;
|
|
|
+#endif
|
|
|
+rndprc = oprec;
|
|
|
+emdnorm( yy, k, 0, lexp, 64 );
|
|
|
+
|
|
|
+aexit:
|
|
|
+
|
|
|
+rndprc = rndsav;
|
|
|
+yy[0] = nsign;
|
|
|
+switch( oprec )
|
|
|
+ {
|
|
|
+#ifdef DEC
|
|
|
+ case 56:
|
|
|
+ todec( yy, y ); /* see etodec.c */
|
|
|
+ break;
|
|
|
+#endif
|
|
|
+ case 53:
|
|
|
+ toe53( yy, y );
|
|
|
+ break;
|
|
|
+ case 24:
|
|
|
+ toe24( yy, y );
|
|
|
+ break;
|
|
|
+ case 64:
|
|
|
+ toe64( yy, y );
|
|
|
+ break;
|
|
|
+ case 113:
|
|
|
+ toe113( yy, y );
|
|
|
+ break;
|
|
|
+ case NBITS:
|
|
|
+ emovo( yy, y );
|
|
|
+ break;
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* y = largest integer not greater than x
|
|
|
+ * (truncated toward minus infinity)
|
|
|
+ *
|
|
|
+ * unsigned short x[NE], y[NE]
|
|
|
+ *
|
|
|
+ * efloor( x, y );
|
|
|
+ */
|
|
|
+static unsigned short bmask[] = {
|
|
|
+0xffff,
|
|
|
+0xfffe,
|
|
|
+0xfffc,
|
|
|
+0xfff8,
|
|
|
+0xfff0,
|
|
|
+0xffe0,
|
|
|
+0xffc0,
|
|
|
+0xff80,
|
|
|
+0xff00,
|
|
|
+0xfe00,
|
|
|
+0xfc00,
|
|
|
+0xf800,
|
|
|
+0xf000,
|
|
|
+0xe000,
|
|
|
+0xc000,
|
|
|
+0x8000,
|
|
|
+0x0000,
|
|
|
+};
|
|
|
+
|
|
|
+void efloor( x, y )
|
|
|
+unsigned short x[], y[];
|
|
|
+{
|
|
|
+register unsigned short *p;
|
|
|
+int e, expon, i;
|
|
|
+unsigned short f[NE];
|
|
|
+
|
|
|
+emov( x, f ); /* leave in external format */
|
|
|
+expon = (int )f[NE-1];
|
|
|
+e = (expon & 0x7fff) - (EXONE - 1);
|
|
|
+if( e <= 0 )
|
|
|
+ {
|
|
|
+ eclear(y);
|
|
|
+ goto isitneg;
|
|
|
+ }
|
|
|
+/* number of bits to clear out */
|
|
|
+e = NBITS - e;
|
|
|
+emov( f, y );
|
|
|
+if( e <= 0 )
|
|
|
+ return;
|
|
|
+
|
|
|
+p = &y[0];
|
|
|
+while( e >= 16 )
|
|
|
+ {
|
|
|
+ *p++ = 0;
|
|
|
+ e -= 16;
|
|
|
+ }
|
|
|
+/* clear the remaining bits */
|
|
|
+*p &= bmask[e];
|
|
|
+/* truncate negatives toward minus infinity */
|
|
|
+isitneg:
|
|
|
+
|
|
|
+if( (unsigned short )expon & (unsigned short )0x8000 )
|
|
|
+ {
|
|
|
+ for( i=0; i<NE-1; i++ )
|
|
|
+ {
|
|
|
+ if( f[i] != y[i] )
|
|
|
+ {
|
|
|
+ esub( eone, y, y );
|
|
|
+ break;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ }
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* unsigned short x[], s[];
|
|
|
+ * long *exp;
|
|
|
+ *
|
|
|
+ * efrexp( x, exp, s );
|
|
|
+ *
|
|
|
+ * Returns s and exp such that s * 2**exp = x and .5 <= s < 1.
|
|
|
+ * For example, 1.1 = 0.55 * 2**1
|
|
|
+ * Handles denormalized numbers properly using long integer exp.
|
|
|
+ */
|
|
|
+void efrexp( x, exp, s )
|
|
|
+unsigned short x[];
|
|
|
+long *exp;
|
|
|
+unsigned short s[];
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+long li;
|
|
|
+
|
|
|
+emovi( x, xi );
|
|
|
+li = (long )((short )xi[1]);
|
|
|
+
|
|
|
+if( li == 0 )
|
|
|
+ {
|
|
|
+ li -= enormlz( xi );
|
|
|
+ }
|
|
|
+xi[1] = 0x3ffe;
|
|
|
+emovo( xi, s );
|
|
|
+*exp = li - 0x3ffe;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* unsigned short x[], y[];
|
|
|
+ * long pwr2;
|
|
|
+ *
|
|
|
+ * eldexp( x, pwr2, y );
|
|
|
+ *
|
|
|
+ * Returns y = x * 2**pwr2.
|
|
|
+ */
|
|
|
+void eldexp( x, pwr2, y )
|
|
|
+unsigned short x[];
|
|
|
+long pwr2;
|
|
|
+unsigned short y[];
|
|
|
+{
|
|
|
+unsigned short xi[NI];
|
|
|
+long li;
|
|
|
+int i;
|
|
|
+
|
|
|
+emovi( x, xi );
|
|
|
+li = xi[1];
|
|
|
+li += pwr2;
|
|
|
+i = 0;
|
|
|
+emdnorm( xi, i, i, li, 64 );
|
|
|
+emovo( xi, y );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+/* c = remainder after dividing b by a
|
|
|
+ * Least significant integer quotient bits left in equot[].
|
|
|
+ */
|
|
|
+void eremain( a, b, c )
|
|
|
+unsigned short a[], b[], c[];
|
|
|
+{
|
|
|
+unsigned short den[NI], num[NI];
|
|
|
+
|
|
|
+#ifdef NANS
|
|
|
+if( eisinf(b) || (ecmp(a,ezero) == 0) || eisnan(a) || eisnan(b))
|
|
|
+ {
|
|
|
+ enan( c, NBITS );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+if( ecmp(a,ezero) == 0 )
|
|
|
+ {
|
|
|
+ mtherr( "eremain", SING );
|
|
|
+ eclear( c );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+emovi( a, den );
|
|
|
+emovi( b, num );
|
|
|
+eiremain( den, num );
|
|
|
+/* Sign of remainder = sign of quotient */
|
|
|
+if( a[0] == b[0] )
|
|
|
+ num[0] = 0;
|
|
|
+else
|
|
|
+ num[0] = 0xffff;
|
|
|
+emovo( num, c );
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+void eiremain( den, num )
|
|
|
+unsigned short den[], num[];
|
|
|
+{
|
|
|
+long ld, ln;
|
|
|
+unsigned short j;
|
|
|
+
|
|
|
+ld = den[E];
|
|
|
+ld -= enormlz( den );
|
|
|
+ln = num[E];
|
|
|
+ln -= enormlz( num );
|
|
|
+ecleaz( equot );
|
|
|
+while( ln >= ld )
|
|
|
+ {
|
|
|
+ if( ecmpm(den,num) <= 0 )
|
|
|
+ {
|
|
|
+ esubm(den, num);
|
|
|
+ j = 1;
|
|
|
+ }
|
|
|
+ else
|
|
|
+ {
|
|
|
+ j = 0;
|
|
|
+ }
|
|
|
+ eshup1(equot);
|
|
|
+ equot[NI-1] |= j;
|
|
|
+ eshup1(num);
|
|
|
+ ln -= 1;
|
|
|
+ }
|
|
|
+emdnorm( num, 0, 0, ln, 0 );
|
|
|
+}
|
|
|
+
|
|
|
+/* NaN bit patterns
|
|
|
+ */
|
|
|
+#ifdef MIEEE
|
|
|
+unsigned short nan113[8] = {
|
|
|
+ 0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff};
|
|
|
+unsigned short nan64[6] = {0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff};
|
|
|
+unsigned short nan53[4] = {0x7fff, 0xffff, 0xffff, 0xffff};
|
|
|
+unsigned short nan24[2] = {0x7fff, 0xffff};
|
|
|
+#endif
|
|
|
+
|
|
|
+#ifdef IBMPC
|
|
|
+unsigned short nan113[8] = {0, 0, 0, 0, 0, 0, 0xc000, 0xffff};
|
|
|
+unsigned short nan64[6] = {0, 0, 0, 0xc000, 0xffff, 0};
|
|
|
+unsigned short nan53[4] = {0, 0, 0, 0xfff8};
|
|
|
+unsigned short nan24[2] = {0, 0xffc0};
|
|
|
+#endif
|
|
|
+
|
|
|
+
|
|
|
+void enan (nan, size)
|
|
|
+unsigned short *nan;
|
|
|
+int size;
|
|
|
+{
|
|
|
+int i, n;
|
|
|
+unsigned short *p;
|
|
|
+
|
|
|
+switch( size )
|
|
|
+ {
|
|
|
+#ifndef DEC
|
|
|
+ case 113:
|
|
|
+ n = 8;
|
|
|
+ p = nan113;
|
|
|
+ break;
|
|
|
+
|
|
|
+ case 64:
|
|
|
+ n = 6;
|
|
|
+ p = nan64;
|
|
|
+ break;
|
|
|
+
|
|
|
+ case 53:
|
|
|
+ n = 4;
|
|
|
+ p = nan53;
|
|
|
+ break;
|
|
|
+
|
|
|
+ case 24:
|
|
|
+ n = 2;
|
|
|
+ p = nan24;
|
|
|
+ break;
|
|
|
+
|
|
|
+ case NBITS:
|
|
|
+ for( i=0; i<NE-2; i++ )
|
|
|
+ *nan++ = 0;
|
|
|
+ *nan++ = 0xc000;
|
|
|
+ *nan++ = 0x7fff;
|
|
|
+ return;
|
|
|
+
|
|
|
+ case NI*16:
|
|
|
+ *nan++ = 0;
|
|
|
+ *nan++ = 0x7fff;
|
|
|
+ *nan++ = 0;
|
|
|
+ *nan++ = 0xc000;
|
|
|
+ for( i=4; i<NI; i++ )
|
|
|
+ *nan++ = 0;
|
|
|
+ return;
|
|
|
+#endif
|
|
|
+ default:
|
|
|
+ mtherr( "enan", DOMAIN );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+for (i=0; i < n; i++)
|
|
|
+ *nan++ = *p++;
|
|
|
+}
|
|
|
+
|
|
|
+
|
|
|
+
|
|
|
+/* Longhand square root. */
|
|
|
+
|
|
|
+static int esqinited = 0;
|
|
|
+static unsigned short sqrndbit[NI];
|
|
|
+
|
|
|
+void esqrt( x, y )
|
|
|
+short *x, *y;
|
|
|
+{
|
|
|
+unsigned short temp[NI], num[NI], sq[NI], xx[NI];
|
|
|
+int i, j, k, n, nlups;
|
|
|
+long m, exp;
|
|
|
+
|
|
|
+if( esqinited == 0 )
|
|
|
+ {
|
|
|
+ ecleaz( sqrndbit );
|
|
|
+ sqrndbit[NI-2] = 1;
|
|
|
+ esqinited = 1;
|
|
|
+ }
|
|
|
+/* Check for arg <= 0 */
|
|
|
+i = ecmp( x, ezero );
|
|
|
+if( i <= 0 )
|
|
|
+ {
|
|
|
+#ifdef NANS
|
|
|
+ if (i == -2)
|
|
|
+ {
|
|
|
+ enan (y, NBITS);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+ eclear(y);
|
|
|
+ if( i < 0 )
|
|
|
+ mtherr( "esqrt", DOMAIN );
|
|
|
+ return;
|
|
|
+ }
|
|
|
+
|
|
|
+#ifdef INFINITY
|
|
|
+if( eisinf(x) )
|
|
|
+ {
|
|
|
+ eclear(y);
|
|
|
+ einfin(y);
|
|
|
+ return;
|
|
|
+ }
|
|
|
+#endif
|
|
|
+/* Bring in the arg and renormalize if it is denormal. */
|
|
|
+emovi( x, xx );
|
|
|
+m = (long )xx[1]; /* local long word exponent */
|
|
|
+if( m == 0 )
|
|
|
+ m -= enormlz( xx );
|
|
|
+
|
|
|
+/* Divide exponent by 2 */
|
|
|
+m -= 0x3ffe;
|
|
|
+exp = (unsigned short )( (m / 2) + 0x3ffe );
|
|
|
+
|
|
|
+/* Adjust if exponent odd */
|
|
|
+if( (m & 1) != 0 )
|
|
|
+ {
|
|
|
+ if( m > 0 )
|
|
|
+ exp += 1;
|
|
|
+ eshdn1( xx );
|
|
|
+ }
|
|
|
+
|
|
|
+ecleaz( sq );
|
|
|
+ecleaz( num );
|
|
|
+n = 8; /* get 8 bits of result per inner loop */
|
|
|
+nlups = rndprc;
|
|
|
+j = 0;
|
|
|
+
|
|
|
+while( nlups > 0 )
|
|
|
+ {
|
|
|
+/* bring in next word of arg */
|
|
|
+ if( j < NE )
|
|
|
+ num[NI-1] = xx[j+3];
|
|
|
+/* Do additional bit on last outer loop, for roundoff. */
|
|
|
+ if( nlups <= 8 )
|
|
|
+ n = nlups + 1;
|
|
|
+ for( i=0; i<n; i++ )
|
|
|
+ {
|
|
|
+/* Next 2 bits of arg */
|
|
|
+ eshup1( num );
|
|
|
+ eshup1( num );
|
|
|
+/* Shift up answer */
|
|
|
+ eshup1( sq );
|
|
|
+/* Make trial divisor */
|
|
|
+ for( k=0; k<NI; k++ )
|
|
|
+ temp[k] = sq[k];
|
|
|
+ eshup1( temp );
|
|
|
+ eaddm( sqrndbit, temp );
|
|
|
+/* Subtract and insert answer bit if it goes in */
|
|
|
+ if( ecmpm( temp, num ) <= 0 )
|
|
|
+ {
|
|
|
+ esubm( temp, num );
|
|
|
+ sq[NI-2] |= 1;
|
|
|
+ }
|
|
|
+ }
|
|
|
+ nlups -= n;
|
|
|
+ j += 1;
|
|
|
+ }
|
|
|
+
|
|
|
+/* Adjust for extra, roundoff loop done. */
|
|
|
+exp += (NBITS - 1) - rndprc;
|
|
|
+
|
|
|
+/* Sticky bit = 1 if the remainder is nonzero. */
|
|
|
+k = 0;
|
|
|
+for( i=3; i<NI; i++ )
|
|
|
+ k |= (int )num[i];
|
|
|
+
|
|
|
+/* Renormalize and round off. */
|
|
|
+emdnorm( sq, k, 0, exp, 64 );
|
|
|
+emovo( sq, y );
|
|
|
+}
|