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[/] [openrisc/] [trunk/] [gnu-src/] [newlib-1.17.0/] [newlib/] [libc/] [stdlib/] [ldtoa.c] - Rev 158
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/* Extended precision arithmetic functions for long double I/O. * This program has been placed in the public domain. */ #include <_ansi.h> #include <reent.h> #include <string.h> #include <stdlib.h> #include "mprec.h" /* These are the externally visible entries. */ /* linux name: long double _IO_strtold (char *, char **); */ long double _strtold (char *, char **); char * _ldtoa_r (struct _reent *, long double, int, int, int *, int *, char **); int _ldcheck (long double *); #if 0 void _IO_ldtostr(long double *, char *, int, int, char); #endif /* Number of 16 bit words in external x type format */ #define NE 10 /* Number of 16 bit words in internal format */ #define NI (NE+3) /* Array offset to exponent */ #define E 1 /* Array offset to high guard word */ #define M 2 /* Number of bits of precision */ #define NBITS ((NI-4)*16) /* Maximum number of decimal digits in ASCII conversion * = NBITS*log10(2) */ #define NDEC (NBITS*8/27) /* The exponent of 1.0 */ #define EXONE (0x3fff) /* Maximum exponent digits - base 10 */ #define MAX_EXP_DIGITS 5 /* Control structure for long double conversion including rounding precision values. * rndprc can be set to 80 (if NE=6), 64, 56, 53, or 24 bits. */ typedef struct { int rlast; int rndprc; int rw; int re; int outexpon; unsigned short rmsk; unsigned short rmbit; unsigned short rebit; unsigned short rbit[NI]; unsigned short equot[NI]; } LDPARMS; static void esub(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp); static void emul(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp); static void ediv(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp); static int ecmp(short unsigned int *a, short unsigned int *b); static int enormlz(short unsigned int *x); static int eshift(short unsigned int *x, int sc); static void eshup1(register short unsigned int *x); static void eshup8(register short unsigned int *x); static void eshup6(register short unsigned int *x); static void eshdn1(register short unsigned int *x); static void eshdn8(register short unsigned int *x); static void eshdn6(register short unsigned int *x); static void eneg(short unsigned int *x); static void emov(register short unsigned int *a, register short unsigned int *b); static void eclear(register short unsigned int *x); static void einfin(register short unsigned int *x, register LDPARMS *ldp); static void efloor(short unsigned int *x, short unsigned int *y, LDPARMS *ldp); static void etoasc(short unsigned int *x, char *string, int ndigs, int outformat, LDPARMS *ldp); union uconv { unsigned short pe; long double d; }; #if LDBL_MANT_DIG == 24 static void e24toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp); #elif LDBL_MANT_DIG == 53 static void e53toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp); #elif LDBL_MANT_DIG == 64 static void e64toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp); #else static void e113toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp); #endif /* econst.c */ /* e type constants used by high precision check routines */ #if NE == 10 /* 0.0 */ static unsigned short ezero[NE] = {0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000,}; /* 1.0E0 */ static unsigned short eone[NE] = {0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x0000, 0x8000, 0x3fff,}; #else /* 0.0 */ static unsigned short ezero[NE] = { 0, 0000000,0000000,0000000,0000000,0000000,}; /* 1.0E0 */ static unsigned short eone[NE] = { 0, 0000000,0000000,0000000,0100000,0x3fff,}; #endif /* Debugging routine for displaying errors */ #ifdef DEBUG /* Notice: the order of appearance of the following * messages is bound to the error codes defined * in mconf.h. */ static char *ermsg[7] = { "unknown", /* error code 0 */ "domain", /* error code 1 */ "singularity", /* et seq. */ "overflow", "underflow", "total loss of precision", "partial loss of precision" }; #define mtherr(name, code) printf( "\n%s %s error\n", name, ermsg[code] ); #else #define mtherr(name, code) #endif /* ieee.c * * Extended precision IEEE binary floating point arithmetic routines * * Numbers are stored in C language as arrays of 16-bit unsigned * short integers. The arguments of the routines are pointers to * the arrays. * * * External e type data structure, simulates Intel 8087 chip * temporary real format but possibly with a larger significand: * * NE-1 significand words (least significant word first, * most significant bit is normally set) * exponent (value = EXONE for 1.0, * top bit is the sign) * * * Internal data structure of a number (a "word" is 16 bits): * * ei[0] sign word (0 for positive, 0xffff for negative) * ei[1] biased exponent (value = EXONE for the number 1.0) * ei[2] high guard word (always zero after normalization) * ei[3] * to ei[NI-2] significand (NI-4 significand words, * most significant word first, * most significant bit is set) * ei[NI-1] low guard word (0x8000 bit is rounding place) * * * * Routines for external format numbers * * asctoe( string, e ) ASCII string to extended double e type * asctoe64( string, &d ) ASCII string to long double * asctoe53( string, &d ) ASCII string to double * asctoe24( string, &f ) ASCII string to single * asctoeg( string, e, prec, ldp ) ASCII string to specified precision * e24toe( &f, e, ldp ) IEEE single precision to e type * e53toe( &d, e, ldp ) IEEE double precision to e type * e64toe( &d, e, ldp ) IEEE long double precision to e type * e113toe( &d, e, ldp ) IEEE long double precision to e type * eabs(e) absolute value * eadd( a, b, c ) c = b + a * eclear(e) e = 0 * 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. * ediv( a, b, c, ldp ) c = b / a * efloor( a, b, ldp ) truncate to integer, toward -infinity * efrexp( a, exp, s ) extract exponent and significand * eifrac( e, &l, frac ) e to long integer and e type fraction * euifrac( e, &l, frac ) e to unsigned long integer and e type fraction * einfin( e, ldp ) set e to infinity, leaving its sign alone * eldexp( a, n, b ) multiply by 2**n * emov( a, b ) b = a * emul( a, b, c, ldp ) c = b * a * eneg(e) e = -e * eround( a, b ) b = nearest integer value to a * esub( a, b, c, ldp ) c = b - a * e24toasc( &f, str, n ) single to ASCII string, n digits after decimal * e53toasc( &d, str, n ) double to ASCII string, n digits after decimal * e64toasc( &d, str, n ) long double to ASCII string * etoasc(e,str,n,fmt,ldp)e to ASCII string, n digits after decimal * etoe24( e, &f ) convert e type to IEEE single precision * etoe53( e, &d ) convert e type to IEEE double precision * etoe64( e, &d ) convert e type to IEEE long double precision * ltoe( &l, e ) long (32 bit) integer to e type * ultoe( &l, e ) unsigned long (32 bit) integer to e type * eisneg( e ) 1 if sign bit of e != 0, else 0 * eisinf( e ) 1 if e has maximum exponent (non-IEEE) * or is infinite (IEEE) * eisnan( e ) 1 if e is a NaN * esqrt( a, b ) b = square root of a * * * Routines for internal format numbers * * eaddm( ai, bi ) add significands, bi = bi + ai * ecleaz(ei) ei = 0 * ecleazs(ei) set ei = 0 but leave its sign alone * ecmpm( ai, bi ) compare significands, return 1, 0, or -1 * edivm( ai, bi, ldp ) divide significands, bi = bi / ai * emdnorm(ai,l,s,exp,ldp) normalize and round off * emovi( a, ai ) convert external a to internal ai * emovo( ai, a, ldp ) convert internal ai to external a * emovz( ai, bi ) bi = ai, low guard word of bi = 0 * emulm( ai, bi, ldp ) multiply significands, bi = bi * ai * enormlz(ei) left-justify the significand * eshdn1( ai ) shift significand and guards down 1 bit * eshdn8( ai ) shift down 8 bits * eshdn6( ai ) shift down 16 bits * eshift( ai, n ) shift ai n bits up (or down if n < 0) * eshup1( ai ) shift significand and guards up 1 bit * eshup8( ai ) shift up 8 bits * eshup6( ai ) shift up 16 bits * esubm( ai, bi ) subtract significands, bi = bi - ai * * * The result is always normalized and rounded to NI-4 word precision * after each arithmetic operation. * * Exception flags are NOT fully supported. * * Define USE_INFINITY in mconf.h for support of infinity; otherwise a * saturation arithmetic is implemented. * * Define NANS for support of Not-a-Number items; otherwise the * arithmetic will never produce a NaN output, and might be confused * by a NaN input. * If NaN's are supported, the output of ecmp(a,b) is -2 if * either a or b is a NaN. This means asking if(ecmp(a,b) < 0) * may not be legitimate. Use if(ecmp(a,b) == -1) for less-than * if in doubt. * Signaling NaN's are NOT supported; they are treated the same * as quiet NaN's. * * Denormals are always supported here where appropriate (e.g., not * for conversion to DEC numbers). */ /* * Revision history: * * 5 Jan 84 PDP-11 assembly language version * 6 Dec 86 C language version * 30 Aug 88 100 digit version, improved rounding * 15 May 92 80-bit long double support * 22 Nov 00 Revised to fit into newlib by Jeff Johnston <jjohnstn@redhat.com> * * Author: S. L. Moshier. * * Copyright (c) 1984,2000 S.L. Moshier * * Permission to use, copy, modify, and distribute this software for any * purpose without fee is hereby granted, provided that this entire notice * is included in all copies of any software which is or includes a copy * or modification of this software and in all copies of the supporting * documentation for such software. * * THIS SOFTWARE IS BEING PROVIDED "AS IS", WITHOUT ANY EXPRESS OR IMPLIED * WARRANTY. IN PARTICULAR, THE AUTHOR MAKES NO REPRESENTATION * OR WARRANTY OF ANY KIND CONCERNING THE MERCHANTABILITY OF THIS * SOFTWARE OR ITS FITNESS FOR ANY PARTICULAR PURPOSE. * */ #include <stdio.h> /* #include "\usr\include\stdio.h" */ /*#include "ehead.h"*/ /*#include "mconf.h"*/ /* mconf.h * * Common include file for math routines * * * * SYNOPSIS: * * #include "mconf.h" * * * * DESCRIPTION: * * This file contains definitions for error codes that are * passed to the common error handling routine mtherr() * (which see). * * The file also includes a conditional assembly definition * for the type of computer arithmetic (IEEE, DEC, Motorola * IEEE, or UNKnown). * * For Digital Equipment PDP-11 and VAX computers, certain * IBM systems, and others that use numbers with a 56-bit * significand, the symbol DEC should be defined. In this * mode, most floating point constants are given as arrays * of octal integers to eliminate decimal to binary conversion * errors that might be introduced by the compiler. * * For computers, such as IBM PC, that follow the IEEE * Standard for Binary Floating Point Arithmetic (ANSI/IEEE * Std 754-1985), the symbol IBMPC should be defined. These * numbers have 53-bit significands. In this mode, constants * are provided as arrays of hexadecimal 16 bit integers. * * To accommodate other types of computer arithmetic, all * constants are also provided in a normal decimal radix * which one can hope are correctly converted to a suitable * format by the available C language compiler. To invoke * this mode, the symbol UNK is defined. * * An important difference among these modes is a predefined * set of machine arithmetic constants for each. The numbers * MACHEP (the machine roundoff error), MAXNUM (largest number * represented), and several other parameters are preset by * the configuration symbol. Check the file const.c to * ensure that these values are correct for your computer. * * For ANSI C compatibility, define ANSIC equal to 1. Currently * this affects only the atan2() function and others that use it. */ /* Constant definitions for math error conditions */ #define DOMAIN 1 /* argument domain error */ #define SING 2 /* argument singularity */ #define OVERFLOW 3 /* overflow range error */ #define UNDERFLOW 4 /* underflow range error */ #define TLOSS 5 /* total loss of precision */ #define PLOSS 6 /* partial loss of precision */ #define EDOM 33 #define ERANGE 34 typedef struct { double r; double i; }cmplx; /* Type of computer arithmetic */ #ifndef DEC #ifdef __IEEE_LITTLE_ENDIAN #define IBMPC 1 #else /* !__IEEE_LITTLE_ENDIAN */ #define MIEEE 1 #endif /* !__IEEE_LITTLE_ENDIAN */ #endif /* !DEC */ /* Define 1 for ANSI C atan2() function * See atan.c and clog.c. */ #define ANSIC 1 /*define VOLATILE volatile*/ #define VOLATILE #define NANS #define USE_INFINITY /* NaN's require infinity support. */ #ifdef NANS #ifndef INFINITY #define USE_INFINITY #endif #endif /* This handles 64-bit long ints. */ #define LONGBITS (8 * sizeof(long)) static void eaddm(short unsigned int *x, short unsigned int *y); static void esubm(short unsigned int *x, short unsigned int *y); static void emdnorm(short unsigned int *s, int lost, int subflg, long int exp, int rcntrl, LDPARMS *ldp); static int asctoeg(char *ss, short unsigned int *y, int oprec, LDPARMS *ldp); static void enan(short unsigned int *nan, int size); #if LDBL_MANT_DIG == 24 static void toe24(short unsigned int *x, short unsigned int *y); #elif LDBL_MANT_DIG == 53 static void toe53(short unsigned int *x, short unsigned int *y); #elif LDBL_MANT_DIG == 64 static void toe64(short unsigned int *a, short unsigned int *b); #else static void toe113(short unsigned int *a, short unsigned int *b); #endif static void eiremain(short unsigned int *den, short unsigned int *num, LDPARMS *ldp); static int ecmpm(register short unsigned int *a, register short unsigned int *b); static int edivm(short unsigned int *den, short unsigned int *num, LDPARMS *ldp); static int emulm(short unsigned int *a, short unsigned int *b, LDPARMS *ldp); static int eisneg(short unsigned int *x); static int eisinf(short unsigned int *x); static void emovi(short unsigned int *a, short unsigned int *b); static void emovo(short unsigned int *a, short unsigned int *b, LDPARMS *ldp); static void emovz(register short unsigned int *a, register short unsigned int *b); static void ecleaz(register short unsigned int *xi); static void eadd1(short unsigned int *a, short unsigned int *b, short unsigned int *c, int subflg, LDPARMS *ldp); static int eisnan(short unsigned int *x); static int eiisnan(short unsigned int *x); #ifdef DEC static void etodec(), todec(), dectoe(); #endif /* ; Clear out entire external format number. ; ; unsigned short x[]; ; eclear( x ); */ static void eclear(register short unsigned int *x) { register int i; for( i=0; i<NE; i++ ) *x++ = 0; } /* Move external format number from a to b. * * emov( a, b ); */ static void emov(register short unsigned int *a, register short unsigned int *b) { register int i; for( i=0; i<NE; i++ ) *b++ = *a++; } /* ; Negate external format number ; ; unsigned short x[NE]; ; eneg( x ); */ static void eneg(short unsigned int *x) { #ifdef NANS if( eisnan(x) ) return; #endif x[NE-1] ^= 0x8000; /* Toggle the sign bit */ } /* Return 1 if external format number is negative, * else return zero. */ static int eisneg(short unsigned int *x) { #ifdef NANS if( eisnan(x) ) return( 0 ); #endif if( x[NE-1] & 0x8000 ) return( 1 ); else return( 0 ); } /* Return 1 if external format number has maximum possible exponent, * else return zero. */ static int eisinf(short unsigned int *x) { if( (x[NE-1] & 0x7fff) == 0x7fff ) { #ifdef NANS if( eisnan(x) ) return( 0 ); #endif return( 1 ); } else return( 0 ); } /* Check if e-type number is not a number. */ static int eisnan(short unsigned int *x) { #ifdef NANS int i; /* NaN has maximum exponent */ if( (x[NE-1] & 0x7fff) != 0x7fff ) return (0); /* ... and non-zero significand field. */ for( i=0; i<NE-1; i++ ) { if( *x++ != 0 ) return (1); } #endif return (0); } /* ; Fill entire number, including exponent and significand, with ; largest possible number. These programs implement a saturation ; value that is an ordinary, legal number. A special value ; "infinity" may also be implemented; this would require tests ; for that value and implementation of special rules for arithmetic ; operations involving inifinity. */ static void einfin(register short unsigned int *x, register LDPARMS *ldp) { register int i; #ifdef USE_INFINITY for( i=0; i<NE-1; i++ ) *x++ = 0; *x |= 32767; ldp = ldp; #else for( i=0; i<NE-1; i++ ) *x++ = 0xffff; *x |= 32766; if( ldp->rndprc < NBITS ) { if (ldp->rndprc == 113) { *(x - 9) = 0; *(x - 8) = 0; } if( ldp->rndprc == 64 ) { *(x-5) = 0; } if( ldp->rndprc == 53 ) { *(x-4) = 0xf800; } else { *(x-4) = 0; *(x-3) = 0; *(x-2) = 0xff00; } } #endif } /* Move in external format number, * converting it to internal format. */ static void emovi(short unsigned int *a, short unsigned int *b) { register unsigned short *p, *q; int i; q = b; p = a + (NE-1); /* point to last word of external number */ /* get the sign bit */ if( *p & 0x8000 ) *q++ = 0xffff; else *q++ = 0; /* get the exponent */ *q = *p--; *q++ &= 0x7fff; /* delete the sign bit */ #ifdef USE_INFINITY if( (*(q-1) & 0x7fff) == 0x7fff ) { #ifdef NANS if( eisnan(a) ) { *q++ = 0; for( i=3; i<NI; i++ ) *q++ = *p--; return; } #endif for( i=2; i<NI; i++ ) *q++ = 0; return; } #endif /* clear high guard word */ *q++ = 0; /* move in the significand */ for( i=0; i<NE-1; i++ ) *q++ = *p--; /* clear low guard word */ *q = 0; } /* Move internal format number out, * converting it to external format. */ static void emovo(short unsigned int *a, short unsigned int *b, LDPARMS *ldp) { register unsigned short *p, *q; unsigned short i; p = a; q = b + (NE-1); /* point to output exponent */ /* combine sign and exponent */ i = *p++; if( i ) *q-- = *p++ | 0x8000; else *q-- = *p++; #ifdef USE_INFINITY if( *(p-1) == 0x7fff ) { #ifdef NANS if( eiisnan(a) ) { enan( b, NBITS ); return; } #endif einfin(b, ldp); return; } #endif /* skip over guard word */ ++p; /* move the significand */ for( i=0; i<NE-1; i++ ) *q-- = *p++; } /* Clear out internal format number. */ static void ecleaz(register short unsigned int *xi) { register int i; for( i=0; i<NI; i++ ) *xi++ = 0; } /* same, but don't touch the sign. */ static void ecleazs(register short unsigned int *xi) { register int i; ++xi; for(i=0; i<NI-1; i++) *xi++ = 0; } /* Move internal format number from a to b. */ static void emovz(register short unsigned int *a, register short unsigned int *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. */ static int eiisnan (short unsigned int *x) { int i; if( (x[E] & 0x7fff) == 0x7fff ) { for( i=M+1; i<NI; i++ ) { if( x[i] != 0 ) return(1); } } return(0); } #if LDBL_MANT_DIG == 64 /* Return nonzero if internal format number is infinite. */ static int eiisinf (unsigned short x[]) { #ifdef NANS if (eiisnan (x)) return (0); #endif if ((x[E] & 0x7fff) == 0x7fff) return (1); return (0); } #endif /* LDBL_MANT_DIG == 64 */ /* ; 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 */ static int ecmpm(register short unsigned int *a, register short unsigned int *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 */ static void eshdn1(register short unsigned int *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 */ static void eshup1(register short unsigned int *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 */ static void eshdn8(register short unsigned int *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 */ static void eshup8(register short unsigned int *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 */ static void eshup6(register short unsigned int *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 */ static void eshdn6(register short unsigned int *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 */ static void eaddm(short unsigned int *x, short unsigned int *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 */ static void esubm(short unsigned int *x, short unsigned int *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 */ /* Multiply significand of e-type number b by 16-bit quantity a, e-type result to c. */ static void m16m(short unsigned int a, short unsigned int *b, short unsigned int *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. */ static int edivm(short unsigned int *den, short unsigned int *num, LDPARMS *ldp) { int i; register unsigned short *p; unsigned long tnum; unsigned short j, tdenm, tquot; unsigned short tprod[NI+1]; unsigned short *equot = ldp->equot; 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 * 0xffffUL) < 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 */ static int emulm(short unsigned int *a, short unsigned int *b, LDPARMS *ldp) { unsigned short *p, *q; unsigned short pprod[NI]; unsigned short j; int i; unsigned short *equot = ldp->equot; 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 ); } /* static void eshow(str, x) char *str; unsigned short *x; { int i; printf( "%s ", str ); for( i=0; i<NI; i++ ) printf( "%04x ", *x++ ); printf( "\n" ); } */ /* * 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 void emdnorm(short unsigned int *s, int lost, int subflg, long int exp, int rcntrl, LDPARMS *ldp) { int i, j; unsigned short r; /* Normalize */ j = enormlz( s ); /* a blank significand could mean either zero or infinity. */ #ifndef USE_INFINITY if( j > NBITS ) { ecleazs( s ); return; } #endif exp -= j; #ifndef USE_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( ldp->rndprc != ldp->rlast ) { ecleaz( ldp->rbit ); switch( ldp->rndprc ) { default: case NBITS: ldp->rw = NI-1; /* low guard word */ ldp->rmsk = 0xffff; ldp->rmbit = 0x8000; ldp->rebit = 1; ldp->re = ldp->rw - 1; break; case 113: ldp->rw = 10; ldp->rmsk = 0x7fff; ldp->rmbit = 0x4000; ldp->rebit = 0x8000; ldp->re = ldp->rw; break; case 64: ldp->rw = 7; ldp->rmsk = 0xffff; ldp->rmbit = 0x8000; ldp->rebit = 1; ldp->re = ldp->rw-1; break; /* For DEC arithmetic */ case 56: ldp->rw = 6; ldp->rmsk = 0xff; ldp->rmbit = 0x80; ldp->rebit = 0x100; ldp->re = ldp->rw; break; case 53: ldp->rw = 6; ldp->rmsk = 0x7ff; ldp->rmbit = 0x0400; ldp->rebit = 0x800; ldp->re = ldp->rw; break; case 24: ldp->rw = 4; ldp->rmsk = 0xff; ldp->rmbit = 0x80; ldp->rebit = 0x100; ldp->re = ldp->rw; break; } ldp->rbit[ldp->re] = ldp->rebit; ldp->rlast = ldp->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) && (ldp->rndprc != NBITS) ) #else if( (exp <= 0) && (ldp->rndprc != 64) && (ldp->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[ldp->rw] & ldp->rmsk; if( ldp->rndprc < NBITS ) { i = ldp->rw + 1; while( i < NI ) { if( s[i] ) r |= 1; s[i] = 0; ++i; } } s[ldp->rw] &= ~ldp->rmsk; if( (r & ldp->rmbit) != 0 ) { if( r == ldp->rmbit ) { if( lost == 0 ) { /* round to even */ if( (s[ldp->re] & ldp->rebit) == 0 ) goto mddone; } else { if( subflg != 0 ) goto mddone; } } eaddm( ldp->rbit, s ); } mddone: #if IBMPC if( (exp <= 0) && (ldp->rndprc != NBITS) ) #else if( (exp <= 0) && (ldp->rndprc != 64) && (ldp->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 USE_INFINITY overf: #endif #ifdef USE_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( (ldp->rndprc < 64) || (ldp->rndprc == 113) ) { s[ldp->rw] &= ~ldp->rmsk; if( ldp->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]; ; LDPARMS *ldp; ; esub( a, b, c, ldp ); c = b - a */ static void esub(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp) { #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 eadd1( a, b, c, 1, ldp ); } static void eadd1(short unsigned int *a, short unsigned int *b, short unsigned int *c, int subflg, LDPARMS *ldp) { unsigned short ai[NI], bi[NI], ci[NI]; int i, lost, j, k; long lt, lta, ltb; #ifdef USE_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, ldp ); done: emovo( bi, c, ldp ); } /* ; Divide. ; ; unsigned short a[NE], b[NE], c[NE]; ; LDPARMS *ldp; ; ediv( a, b, c, ldp ); c = b / a */ static void ediv(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp) { 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 USE_INFINITY if( eisinf(b) ) { if( eisneg(a) ^ eisneg(b) ) *(c+(NE-1)) = 0x8000; else *(c+(NE-1)) = 0; einfin(c, ldp); 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, ldp); mtherr( "ediv", SING ); return; } dnzro2: i = edivm( ai, bi, ldp ); /* calculate exponent */ lt = ltb - lta + EXONE; emdnorm( bi, i, 0, lt, 64, ldp ); /* set the sign */ if( ai[0] == bi[0] ) bi[0] = 0; else bi[0] = 0Xffff; emovo( bi, c, ldp ); } /* ; Multiply. ; ; unsigned short a[NE], b[NE], c[NE]; ; LDPARMS *ldp ; emul( a, b, c, ldp ); c = b * a */ static void emul(short unsigned int *a, short unsigned int *b, short unsigned int *c, LDPARMS *ldp) { 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 USE_INFINITY if( eisinf(a) || eisinf(b) ) { if( eisneg(a) ^ eisneg(b) ) *(c+(NE-1)) = 0x8000; else *(c+(NE-1)) = 0; einfin(c, ldp); 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, ldp ); /* calculate exponent */ lt = lta + ltb - (EXONE - 1); emdnorm( bi, j, 0, lt, 64, ldp ); /* calculate sign of product */ if( ai[0] == bi[0] ) bi[0] = 0; else bi[0] = 0xffff; emovo( bi, c, ldp ); } #if LDBL_MANT_DIG > 64 static void e113toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp) { 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 USE_INFINITY if( r == 0x7fff ) { #ifdef NANS #ifdef IBMPC for( i=0; i<7; i++ ) { if( pe[i] != 0 ) { enan( y, NBITS ); return; } } #else /* !IBMPC */ for( i=1; i<8; i++ ) { if( pe[i] != 0 ) { enan( y, NBITS ); return; } } #endif /* !IBMPC */ #endif /* NANS */ eclear( y ); einfin( y, ldp ); 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); #else /* IBMPC */ ++e; for( i=0; i<7; i++ ) *p++ = *e++; #endif /* IBMPC */ /* 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,ldp); } /* move out internal format to ieee long double */ static void toe113(short unsigned int *a, short unsigned int *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 } #endif /* LDBL_MANT_DIG > 64 */ #if LDBL_MANT_DIG == 64 static void e64toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp) { 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; /* MIEEE skips over 2nd short */ 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,ldp); return; } #endif #ifdef USE_INFINITY /* Point to the exponent field. */ p = &yy[NE-1]; if( (*p & 0x7fff) == 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; } } #endif #ifdef MIEEE for( i=2; i<=5; i++ ) { if( pe[i] != 0 ) { enan( y, NBITS ); return; } } #endif #endif /* NANS */ eclear( y ); einfin( y, ldp ); if( *p & 0x8000 ) eneg(y); return; } #endif /* USE_INFINITY */ p = yy; q = y; for( i=0; i<NE; i++ ) *q++ = *p++; } /* move out internal format to ieee long double */ static void toe64(short unsigned int *a, short unsigned int *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 */ /* NOTE: Intel data type is 96 bits wide, clear the last word here. */ *(q+1)= 0; #endif /* combine sign and exponent */ i = *p++; #ifdef MIEEE if( i ) *q++ = *p++ | 0x8000; else *q++ = *p++; *q++ = 0; /* leave 2nd short blank */ #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 USE_INFINITY #ifdef IBMPC if (eiisinf (a)) { /* Intel long double infinity. */ *q-- = 0x8000; *q-- = 0; *q-- = 0; *q = 0; return; } #endif /* IBMPC */ #endif /* USE_INFINITY */ for( i=0; i<4; i++ ) *q-- = *p++; #endif } #endif /* LDBL_MANT_DIG == 64 */ #if LDBL_MANT_DIG == 53 /* ; Convert IEEE double precision to e type ; double d; ; unsigned short x[N+2]; ; e53toe( &d, x ); */ static void e53toe(short unsigned int *pe, short unsigned int *y, LDPARMS *ldp) { #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 #ifdef DEC 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 USE_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 /* !IBMPC */ if( ((pe[0] & 0xf) != 0) || (pe[1] != 0) || (pe[2] != 0) || (pe[3] != 0) ) { enan( y, NBITS ); return; } #endif /* !IBMPC */ #endif /* NANS */ eclear( y ); einfin( y, ldp ); 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); #else /* !IBMPC */ ++e; *p++ = *e++; *p++ = *e++; *p++ = *e++; #endif /* !IBMPC */ (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, ldp ); #endif /* !DEC */ } /* ; e type to IEEE double precision ; double d; ; unsigned short x[NE]; ; etoe53( x, &d ); */ #ifdef DEC static 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 static void toe53(short unsigned int *x, short unsigned int *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 #ifdef DEC 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 USE_INFINITY *y |= 0x7ff0; #ifdef IBMPC *(--y) = 0; *(--y) = 0; *(--y) = 0; #else /* !IBMPC */ ++y; *y++ = 0; *y++ = 0; *y++ = 0; #endif /* IBMPC */ #else /* !USE_INFINITY */ *y |= (unsigned short )0x7fef; #ifdef IBMPC *(--y) = 0xffff; *(--y) = 0xffff; *(--y) = 0xffff; #else /* !IBMPC */ ++y; *y++ = 0xffff; *y++ = 0xffff; *y++ = 0xffff; #endif #endif /* !USE_INFINITY */ 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; #else /* !IBMPC */ ++y; *y++ = *p++; *y++ = *p++; *y++ = *p++; #endif /* !IBMPC */ } #endif /* not DEC */ #endif /* LDBL_MANT_DIG == 53 */ #if LDBL_MANT_DIG == 24 /* ; Convert IEEE single precision to e type ; float d; ; unsigned short x[N+2]; ; dtox( &d, x ); */ void e24toe( short unsigned int *pe, short unsigned int *y, LDPARMS *ldp ) { 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 USE_INFINITY if( r == 0x7f80 ) { #ifdef NANS #ifdef MIEEE if( ((pe[0] & 0x7f) != 0) || (pe[1] != 0) ) { enan( y, NBITS ); return; } #else /* !MIEEE */ if( ((pe[1] & 0x7f) != 0) || (pe[0] != 0) ) { enan( y, NBITS ); return; } #endif /* !MIEEE */ #endif /* NANS */ eclear( y ); einfin( y, ldp ); 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, ldp ); } static void toe24(short unsigned int *x, short unsigned int *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 USE_INFINITY *y |= (unsigned short )0x7f80; #ifdef IBMPC *(--y) = 0; #endif #ifdef DEC *(--y) = 0; #endif #ifdef MIEEE ++y; *y = 0; #endif #else /* !USE_INFINITY */ *y |= (unsigned short )0x7f7f; #ifdef IBMPC *(--y) = 0xffff; #endif #ifdef DEC *(--y) = 0xffff; #endif #ifdef MIEEE ++y; *y = 0xffff; #endif #endif /* !USE_INFINITY */ 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 } #endif /* LDBL_MANT_DIG == 24 */ /* 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. */ static int ecmp(short unsigned int *a, short unsigned int *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 */ } /* ; Shift significand ; ; Shifts significand area up or down by the number of bits ; given by the variable sc. */ static int eshift(short unsigned int *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. */ static int enormlz(short unsigned int *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 /* ASCII string outputs for unix */ #if 0 void _IO_ldtostr(x, string, ndigs, flags, fmt) long double *x; char *string; int ndigs; int flags; char fmt; { unsigned short w[NI]; char *t, *u; LDPARMS rnd; LDPARMS *ldp = &rnd; rnd.rlast = -1; rnd.rndprc = NBITS; if (sizeof(long double) == 16) e113toe( (unsigned short *)x, w, ldp ); else e64toe( (unsigned short *)x, w, ldp ); etoasc( w, string, ndigs, -1, ldp ); if( ndigs == 0 && flags == 0 ) { /* Delete the decimal point unless alternate format. */ t = string; while( *t != '.' ) ++t; u = t + 1; while( *t != '\0' ) *t++ = *u++; } if (*string == ' ') { t = string; u = t + 1; while( *t != '\0' ) *t++ = *u++; } if (fmt == 'E') { t = string; while( *t != 'e' ) ++t; *t = 'E'; } } #endif /* This routine will not return more than NDEC+1 digits. */ char * _ldtoa_r (struct _reent *ptr, long double d, int mode, int ndigits, int *decpt, int *sign, char **rve) { unsigned short e[NI]; char *s, *p; int i, j, k; int orig_ndigits; LDPARMS rnd; LDPARMS *ldp = &rnd; char *outstr; char outbuf[NDEC + MAX_EXP_DIGITS + 10]; union uconv du; du.d = d; orig_ndigits = ndigits; rnd.rlast = -1; rnd.rndprc = NBITS; _REENT_CHECK_MP(ptr); /* reentrancy addition to use mprec storage pool */ if (_REENT_MP_RESULT(ptr)) { _REENT_MP_RESULT(ptr)->_k = _REENT_MP_RESULT_K(ptr); _REENT_MP_RESULT(ptr)->_maxwds = 1 << _REENT_MP_RESULT_K(ptr); Bfree (ptr, _REENT_MP_RESULT(ptr)); _REENT_MP_RESULT(ptr) = 0; } #if LDBL_MANT_DIG == 24 e24toe( &du.pe, e, ldp ); #elif LDBL_MANT_DIG == 53 e53toe( &du.pe, e, ldp ); #elif LDBL_MANT_DIG == 64 e64toe( &du.pe, e, ldp ); #else e113toe( &du.pe, e, ldp ); #endif if( eisneg(e) ) *sign = 1; else *sign = 0; /* Mode 3 is "f" format. */ if( mode != 3 ) ndigits -= 1; /* Mode 0 is for %.999 format, which is supposed to give a minimum length string that will convert back to the same binary value. For now, just ask for 20 digits which is enough but sometimes too many. */ if( mode == 0 ) ndigits = 20; /* This sanity limit must agree with the corresponding one in etoasc, to keep straight the returned value of outexpon. */ if( ndigits > NDEC ) ndigits = NDEC; etoasc( e, outbuf, ndigits, mode, ldp ); s = outbuf; if( eisinf(e) || eisnan(e) ) { *decpt = 9999; goto stripspaces; } *decpt = ldp->outexpon + 1; /* Transform the string returned by etoasc into what the caller wants. */ /* Look for decimal point and delete it from the string. */ s = outbuf; while( *s != '\0' ) { if( *s == '.' ) goto yesdecpt; ++s; } goto nodecpt; yesdecpt: /* Delete the decimal point. */ while( *s != '\0' ) { *s = *(s+1); ++s; } nodecpt: /* Back up over the exponent field. */ while( *s != 'E' && s > outbuf) --s; *s = '\0'; stripspaces: /* Strip leading spaces and sign. */ p = outbuf; while( *p == ' ' || *p == '-') ++p; /* Find new end of string. */ s = outbuf; while( (*s++ = *p++) != '\0' ) ; --s; /* Strip trailing zeros. */ if( mode == 2 ) k = 1; else if( ndigits > ldp->outexpon ) k = ndigits; else k = ldp->outexpon; while( *(s-1) == '0' && ((s - outbuf) > k)) *(--s) = '\0'; /* In f format, flush small off-scale values to zero. Rounding has been taken care of by etoasc. */ if( mode == 3 && ((ndigits + ldp->outexpon) < 0)) { s = outbuf; *s = '\0'; *decpt = 0; } /* reentrancy addition to use mprec storage pool */ /* we want to have enough space to hold the formatted result */ if (mode == 3) /* f format, account for sign + dec digits + decpt + frac */ i = *decpt + orig_ndigits + 3; else /* account for sign + max precision digs + E + exp sign + exponent */ i = orig_ndigits + MAX_EXP_DIGITS + 4; j = sizeof (__ULong); for (_REENT_MP_RESULT_K(ptr) = 0; sizeof (_Bigint) - sizeof (__ULong) + j <= i; j <<= 1) _REENT_MP_RESULT_K(ptr)++; _REENT_MP_RESULT(ptr) = Balloc (ptr, _REENT_MP_RESULT_K(ptr)); /* Copy from internal temporary buffer to permanent buffer. */ outstr = (char *)_REENT_MP_RESULT(ptr); strcpy (outstr, outbuf); if( rve ) *rve = outstr + (s - outbuf); return outstr; } /* Routine used to tell if long double is NaN or Infinity or regular number. Returns: 0 = regular number 1 = Nan 2 = Infinity */ int _ldcheck (long double *d) { unsigned short e[NI]; LDPARMS rnd; LDPARMS *ldp = &rnd; union uconv du; rnd.rlast = -1; rnd.rndprc = NBITS; du.d = *d; #if LDBL_MANT_DIG == 24 e24toe( &du.pe, e, ldp ); #elif LDBL_MANT_DIG == 53 e53toe( &du.pe, e, ldp ); #elif LDBL_MANT_DIG == 64 e64toe( &du.pe, e, ldp ); #else e113toe( &du.pe, e, ldp ); #endif if( (e[NE-1] & 0x7fff) == 0x7fff ) { #ifdef NANS if( eisnan(e) ) return( 1 ); #endif return( 2 ); } else return( 0 ); } /* _ldcheck */ static void etoasc(short unsigned int *x, char *string, int ndigits, int outformat, LDPARMS *ldp) { 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, ndigs; char *s, *ss; unsigned short m; unsigned short *equot = ldp->equot; ndigs = ndigits; rndsav = ldp->rndprc; #ifdef NANS if( eisnan(x) ) { sprintf( string, " NaN " ); expon = 9999; goto bxit; } #endif ldp->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 " ); expon = 9999; 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" ); expon = 9999; 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, ldp ); efloor( t, w, ldp ); 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, ldp ); emul( p, t, t, ldp ); 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, ldp ); 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, ldp ); } 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, ldp ); emul( r, t, t, ldp ); expon += k; } k /= 2; if( k == 0 ) break; p += NE; r += NE; } ediv( t, eone, t, ldp ); } isone: /* Find the first (leading) digit. */ emovi( t, w ); emovz( w, t ); emovi( y, w ); emovz( w, y ); eiremain( t, y, ldp ); 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, ldp ); digit = equot[NI-1]; expon -= 1; } s = string; if( sign ) *s++ = '-'; else *s++ = ' '; /* Examine number of digits requested by caller. */ if( outformat == 3 ) ndigs += expon; /* else 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; if( ndigs < 0 ) { ss = s; goto doexp; } } 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, ldp ); *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, ldp ); if( ecmp(t,ezero) != 0 ) goto roun; /* round to nearest */ if( ndigs < 0 || (*(s-1-(*(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( ndigs < 0 ) { /* This will print like "1E-6". */ *s = '1'; expon += 1; goto doexp; } else 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: #ifdef __GO32__ if( expon >= 0 ) sprintf( ss, "e+%02d", expon ); else sprintf( ss, "e-%02d", -expon ); #else sprintf( ss, "E%d", expon ); #endif bxit: ldp->rndprc = rndsav; ldp->outexpon = expon; } /* ; 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 ); */ long double _strtold (char *s, char **se) { union uconv x; LDPARMS rnd; LDPARMS *ldp = &rnd; int lenldstr; rnd.rlast = -1; rnd.rndprc = NBITS; lenldstr = asctoeg( s, &x.pe, LDBL_MANT_DIG, ldp ); if (se) *se = s + lenldstr; return x.d; } #define REASONABLE_LEN 200 static int asctoeg(char *ss, short unsigned int *y, int oprec, LDPARMS *ldp) { 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, *lstr; int lenldstr; int mflag = 0; char tmpstr[REASONABLE_LEN]; /* Copy the input string. */ c = strlen (ss) + 2; if (c <= REASONABLE_LEN) lstr = tmpstr; else { lstr = (char *) calloc (c, 1); mflag = 1; } s = ss; lenldstr = 0; while( *s == ' ' ) /* skip leading spaces */ { ++s; ++lenldstr; } sp = lstr; for( k=0; k<c; k++ ) { if( (*sp++ = *s++) == '\0' ) break; } *sp = '\0'; s = lstr; rndsav = ldp->rndprc; ldp->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, ldp ); /* 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, ldp ); lexp += EXONE; nexp -= 4096; } } p = &etens[NTEN][0]; emov( eone, xt ); exp = 1; do { if( exp & nexp ) emul( p, xt, xt, ldp ); p -= NE; exp = exp + exp; } while( exp <= MAXP ); emovi( xt, tt ); if( esign < 0 ) { lexp -= tt[E]; k = edivm( tt, yy, ldp ); lexp += EXONE; } else { lexp += tt[E]; k = emulm( tt, yy, ldp ); 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 ldp->rndprc = oprec; emdnorm( yy, k, 0, lexp, 64, ldp ); aexit: ldp->rndprc = rndsav; yy[0] = nsign; switch( oprec ) { #ifdef DEC case 56: todec( yy, y ); /* see etodec.c */ break; #endif #if LDBL_MANT_DIG == 53 case 53: toe53( yy, y ); break; #elif LDBL_MANT_DIG == 24 case 24: toe24( yy, y ); break; #elif LDBL_MANT_DIG == 64 case 64: toe64( yy, y ); break; #elif LDBL_MANT_DIG == 113 case 113: toe113( yy, y ); break; #else case NBITS: emovo( yy, y, ldp ); break; #endif } lenldstr += s - lstr; if (mflag) free (lstr); return lenldstr; } /* y = largest integer not greater than x * (truncated toward minus infinity) * * unsigned short x[NE], y[NE] * LDPARMS *ldp * * efloor( x, y, ldp ); */ static unsigned short bmask[] = { 0xffff, 0xfffe, 0xfffc, 0xfff8, 0xfff0, 0xffe0, 0xffc0, 0xff80, 0xff00, 0xfe00, 0xfc00, 0xf800, 0xf000, 0xe000, 0xc000, 0x8000, 0x0000, }; static void efloor(short unsigned int *x, short unsigned int *y, LDPARMS *ldp) { 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, ldp ); break; } } } } static void eiremain(short unsigned int *den, short unsigned int *num, LDPARMS *ldp) { long ld, ln; unsigned short j; unsigned short *equot = ldp->equot; 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, ldp ); } /* NaN bit patterns */ #ifdef MIEEE static unsigned short nan113[8] = { 0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff}; static unsigned short nan64[6] = {0x7fff, 0xffff, 0xffff, 0xffff, 0xffff, 0xffff}; static unsigned short nan53[4] = {0x7fff, 0xffff, 0xffff, 0xffff}; static unsigned short nan24[2] = {0x7fff, 0xffff}; #else /* !MIEEE */ static unsigned short nan113[8] = {0, 0, 0, 0, 0, 0, 0x8000, 0x7fff}; static unsigned short nan64[6] = {0, 0, 0, 0, 0xc000, 0x7fff}; static unsigned short nan53[4] = {0, 0, 0, 0x7ff8}; static unsigned short nan24[2] = {0, 0x7fc0}; #endif /* !MIEEE */ static void enan (short unsigned int *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++; }