diff options
Diffstat (limited to 'x68/_dtos18.c')
| -rw-r--r-- | x68/_dtos18.c | 250 |
1 files changed, 250 insertions, 0 deletions
diff --git a/x68/_dtos18.c b/x68/_dtos18.c new file mode 100644 index 0000000000..67656486ec --- /dev/null +++ b/x68/_dtos18.c @@ -0,0 +1,250 @@ +/* + * PROJECT C Library, X68000 PROGRAMMING INTERFACE DEFINITION + * -------------------------------------------------------------------- + * This file is written by the Project C Library Group, and completely + * in public domain. You can freely use, copy, modify, and redistribute + * the whole contents, without this notice. + * -------------------------------------------------------------------- + * $Id: _dtos18.c,v 1.2 1994/11/27 13:05:20 mura Exp $ + */ + +/* System headers */ +#include <stdlib.h> +#include <sys/xstdlib.h> + +/* +** �ܴؿ�����ư���������������������Ѵ����Ƥ���ʸ����ˤ��뤿�ᡢ����Ū�ˤ� +** �����������˳�Ǽ�Ǥ������ޤǤ����������Ȥ��Ǥ��ʤ����������äƺǹ����� +** ��18��Ǥ��롣 +*/ + +/* File scope variables */ +static double _pos1[32] = { + 1.0e+17, /* + 0 */ + 1.0e+18, /* + 1 */ + 1.0e+19, /* + 2 */ + 1.0e+20, /* + 3 */ + 1.0e+21, /* + 4 */ + 1.0e+22, /* + 5 */ + 1.0e+23, /* + 6 */ + 1.0e+24, /* + 7 */ + 1.0e+25, /* + 8 */ + 1.0e+26, /* + 9 */ + 1.0e+27, /* +10 */ + 1.0e+28, /* +11 */ + 1.0e+29, /* +12 */ + 1.0e+30, /* +13 */ + 1.0e+31, /* +14 */ + 1.0e+32, /* +15 */ + 1.0e+33, /* +16 */ + 1.0e+34, /* +17 */ + 1.0e+35, /* +18 */ + 1.0e+36, /* +19 */ + 1.0e+37, /* +20 */ + 1.0e+38, /* +21 */ + 1.0e+39, /* +22 */ + 1.0e+40, /* +23 */ + 1.0e+41, /* +24 */ + 1.0e+42, /* +25 */ + 1.0e+43, /* +26 */ + 1.0e+44, /* +27 */ + 1.0e+45, /* +28 */ + 1.0e+46, /* +29 */ + 1.0e+47, /* +30 */ + 1.0e+48, /* +31 */ +}; + +/* File scope variables */ +static double _neg1[32] = { + 1.0e+17, /* - 0 */ + 1.0e+16, /* - 1 */ + 1.0e+15, /* - 2 */ + 1.0e+14, /* - 3 */ + 1.0e+13, /* - 4 */ + 1.0e+12, /* - 5 */ + 1.0e+11, /* - 6 */ + 1.0e+10, /* - 7 */ + 1.0e+9, /* - 8 */ + 1.0e+8, /* - 9 */ + 1.0e+7, /* -10 */ + 1.0e+6, /* -11 */ + 1.0e+5, /* -12 */ + 1.0e+4, /* -13 */ + 1.0e+3, /* -14 */ + 1.0e+2, /* -15 */ + 1.0e+1, /* -16 */ + 1.0e+0, /* -17 */ + 1.0e-1, /* -18 */ + 1.0e-2, /* -19 */ + 1.0e-3, /* -20 */ + 1.0e-4, /* -21 */ + 1.0e-5, /* -22 */ + 1.0e-6, /* -23 */ + 1.0e-7, /* -24 */ + 1.0e-8, /* -25 */ + 1.0e-9, /* -26 */ + 1.0e-10, /* -27 */ + 1.0e-11, /* -28 */ + 1.0e-12, /* -29 */ + 1.0e-13, /* -30 */ + 1.0e-14, /* -31 */ +}; + +/* File scope variables */ +static double _pos2[10] = { + 1.0e+0, /* 000 */ + 1.0e+32, /* 001 */ + 1.0e+64, /* 010 */ + 1.0e+96, /* 011 */ + 1.0e+128, /* 100 */ + 1.0e+160, /* 101 */ + 1.0e+192, /* 110 */ + 1.0e+224, /* 111 */ + 1.0e+256, /* 1000 */ + 1.0e+288, /* 1001 */ +}; + +/* File scope variables */ +static double _neg2[10] = { + 1.0e-0, /* 000 */ + 1.0e-32, /* 001 */ + 1.0e-64, /* 010 */ + 1.0e-96, /* 011 */ + 1.0e-128, /* 100 */ + 1.0e-160, /* 101 */ + 1.0e-192, /* 110 */ + 1.0e-224, /* 111 */ + 1.0e-256, /* 1000 */ + 1.0e-288, /* 1001 */ +}; + +/* File scope functions */ +static int _cmpd (double x, double y) +{ + unsigned long vx, vy, rc; + unsigned long *x_ptr = (unsigned long *) &x; + unsigned long *y_ptr = (unsigned long *) &y; + + /* x�λؿ��ӥåȤ���Ф� */ + vx = x_ptr[0] & 0x7FF00000; + + /* y�λؿ��ӥåȤ���Ф� */ + vy = y_ptr[0] & 0x7FF00000; + + /* �ؿ��ӥåȤ�����Ƚ�Ǥ��� */ + if ((rc = vy - vx) != 0) + return rc; + + /* x��ͭ�������ξ�̥ӥåȤ���Ф� */ + vx = x_ptr[0] & 0x000FFFFF; + + /* y��ͭ�������ξ�̥ӥåȤ���Ф� */ + vy = y_ptr[0] & 0x000FFFFF; + + /* ��̥ӥåȤ�����Ƚ�Ǥ��� */ + if ((rc = vy - vx) != 0) + return rc; + + /* x��ͭ�������β��̥ӥåȤ���Ф� */ + vx = x_ptr[1]; + + /* y��ͭ�������β��̥ӥåȤ���Ф� */ + vy = y_ptr[1]; + + /* �ǽ�Ƚ�� */ + return vy - vx; +} + +/* Functions */ +void _dtos18 (double x, int *decpt, int *sign, char *buffer) +{ + short e2; + int e, n; + + /* ���2�λؿ������(�Х������ʤ��ξ���) */ + e2 = (((unsigned short *) &x)[0] & 0x7FF0U) >> 4; + + /* �ؿ���0�ξ��ϡ�0.0�����å� */ + if (e2 == 0) { + + unsigned long hi = ((unsigned long *) &x)[0] & 0xFFFFF; + unsigned long lo = ((unsigned long *) &x)[1]; + + /* ͭ������������0���ɤ��� */ + if (hi == 0 && lo == 0) { + + /* ʸ��������� */ + buffer[0] = '0'; + + /* NUL������ */ + buffer[1] = '\0'; + + /* ���������֤�� */ + *decpt = 1; + + /* ����� */ + /* *sign = hi & 0x80000000UL; */ + *sign = 0; + + /* ���� */ + return; + + } + + } + + /* 2�λؿ��˥Х��������Ƥ���10�λؿ��� (approx. log10(2)) */ + e = ((int) ((e2 - 1023) * 77)) >> 8; + + /* �ؿ������ξ�� */ + if (e >= 0) { + + /* �ؿ���32��꾮�������ϥơ��֥�1���� */ + if (e < 32) + x *= _neg1[e]; + + /* �ؿ���32����礭�����ϥơ��֥�1,2���� */ + else + x *= _neg1[e & 31] * _neg2[e >> 5]; + + } + + /* �ؿ�����ξ�� */ + else { + + /* �����ͤ�� */ + n = -e; + + /* �����ͤ�32��꾮�������ϥơ��֥�1���� */ + if (n < 32) + x *= _pos1[n]; + + /* �����ͤ�32����礭�����ϥơ��֥�1,2���� */ + else { + x *= _pos1[n & 31]; + x *= _pos2[n >> 5]; + } + + } + + /* ��������������������᤹ */ + if (_cmpd (1.0e+18, x) >= 0) { + e++; + x *= 1.0e-1; + } + + /* �����������ʤ������ɲ� */ + else if (_cmpd (1.0e+17, x) < 0) { + e--; + x *= 1.0e+1; + } + + /* ���������֤�� */ + *decpt = e + 1; + + /* ����� */ + *sign = ((unsigned char *) &x)[0] & 0x80U; + + /* ʸ������Ѵ� */ + _ulltoa ((unsigned long long) x, buffer); +} |