WebSVN – planix.SVN – Blame – /os/branches/feature_fixcpp/sys/src/ape/lib/ap/stdio/_fconv.c

Rev	Author	Line No.	Line
2	-	1	`/* Common routines for _dtoa and strtod */`
		2
		3	`#include "fconv.h"`
		4
		5	`#ifdef DEBUG`
		6	`#include <stdio.h>`
		7	`#define Bug(x) {fprintf(stderr, "%s\n", x); exit(1);}`
		8	`#endif`
		9
		10	`double`
		11	`_tens[] = {`
		12	`1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,`
		13	`1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,`
		14	`1e20, 1e21, 1e22`
		15	`#ifdef VAX`
		16	`, 1e23, 1e24`
		17	`#endif`
		18	`};`
		19
		20
		21	`#ifdef IEEE_Arith`
		22	`double _bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };`
		23	`double _tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128, 1e-256 };`
		24	`#else`
		25	`#ifdef IBM`
		26	`double _bigtens[] = { 1e16, 1e32, 1e64 };`
		27	`double _tinytens[] = { 1e-16, 1e-32, 1e-64 };`
		28	`#else`
		29	`double _bigtens[] = { 1e16, 1e32 };`
		30	`double _tinytens[] = { 1e-16, 1e-32 };`
		31	`#endif`
		32	`#endif`
		33
		34	`static Bigint *freelist[Kmax+1];`
		35
		36	`Bigint *`
		37	`_Balloc(int k)`
		38	`{`
		39	`int x;`
		40	`Bigint *rv;`
		41
		42	`if (rv = freelist[k]) {`
		43	`freelist[k] = rv->next;`
		44	`}`
		45	`else {`
		46	`x = 1 << k;`
		47	`rv = (Bigint )malloc(sizeof(Bigint) + (x-1)sizeof(long));`
		48	`rv->k = k;`
		49	`rv->maxwds = x;`
		50	`}`
		51	`rv->sign = rv->wds = 0;`
		52	`return rv;`
		53	`}`
		54
		55	`void`
		56	`_Bfree(Bigint *v)`
		57	`{`
		58	`if (v) {`
		59	`v->next = freelist[v->k];`
		60	`freelist[v->k] = v;`
		61	`}`
		62	`}`
		63
		64
		65	`Bigint *`
		66	`_multadd(Bigint b, int m, int a) / multiply by m and add a */`
		67	`{`
		68	`int i, wds;`
		69	`unsigned long *x, y;`
		70	`#ifdef Pack_32`
		71	`unsigned long xi, z;`
		72	`#endif`
		73	`Bigint *b1;`
		74
		75	`wds = b->wds;`
		76	`x = b->x;`
		77	`i = 0;`
		78	`do {`
		79	`#ifdef Pack_32`
		80	`xi = *x;`
		81	`y = (xi & 0xffff) * m + a;`
		82	`z = (xi >> 16) * m + (y >> 16);`
		83	`a = (int)(z >> 16);`
		84	`*x++ = (z << 16) + (y & 0xffff);`
		85	`#else`
		86	`y = x m + a;`
		87	`a = (int)(y >> 16);`
		88	`*x++ = y & 0xffff;`
		89	`#endif`
		90	`}`
		91	`while(++i < wds);`
		92	`if (a) {`
		93	`if (wds >= b->maxwds) {`
		94	`b1 = Balloc(b->k+1);`
		95	`Bcopy(b1, b);`
		96	`Bfree(b);`
		97	`b = b1;`
		98	`}`
		99	`b->x[wds++] = a;`
		100	`b->wds = wds;`
		101	`}`
		102	`return b;`
		103	`}`
		104
		105	`int`
		106	`_hi0bits(register unsigned long x)`
		107	`{`
		108	`register int k = 0;`
		109
		110	`if (!(x & 0xffff0000)) {`
		111	`k = 16;`
		112	`x <<= 16;`
		113	`}`
		114	`if (!(x & 0xff000000)) {`
		115	`k += 8;`
		116	`x <<= 8;`
		117	`}`
		118	`if (!(x & 0xf0000000)) {`
		119	`k += 4;`
		120	`x <<= 4;`
		121	`}`
		122	`if (!(x & 0xc0000000)) {`
		123	`k += 2;`
		124	`x <<= 2;`
		125	`}`
		126	`if (!(x & 0x80000000)) {`
		127	`k++;`
		128	`if (!(x & 0x40000000))`
		129	`return 32;`
		130	`}`
		131	`return k;`
		132	`}`
		133
		134	`static int`
		135	`lo0bits(unsigned long *y)`
		136	`{`
		137	`register int k;`
		138	`register unsigned long x = *y;`
		139
		140	`if (x & 7) {`
		141	`if (x & 1)`
		142	`return 0;`
		143	`if (x & 2) {`
		144	`*y = x >> 1;`
		145	`return 1;`
		146	`}`
		147	`*y = x >> 2;`
		148	`return 2;`
		149	`}`
		150	`k = 0;`
		151	`if (!(x & 0xffff)) {`
		152	`k = 16;`
		153	`x >>= 16;`
		154	`}`
		155	`if (!(x & 0xff)) {`
		156	`k += 8;`
		157	`x >>= 8;`
		158	`}`
		159	`if (!(x & 0xf)) {`
		160	`k += 4;`
		161	`x >>= 4;`
		162	`}`
		163	`if (!(x & 0x3)) {`
		164	`k += 2;`
		165	`x >>= 2;`
		166	`}`
		167	`if (!(x & 1)) {`
		168	`k++;`
		169	`x >>= 1;`
		170	`if (!x & 1)`
		171	`return 32;`
		172	`}`
		173	`*y = x;`
		174	`return k;`
		175	`}`
		176
		177	`Bigint *`
		178	`_i2b(int i)`
		179	`{`
		180	`Bigint *b;`
		181
		182	`b = Balloc(1);`
		183	`b->x[0] = i;`
		184	`b->wds = 1;`
		185	`return b;`
		186	`}`
		187
		188	`Bigint *`
		189	`_mult(Bigint a, Bigint b)`
		190	`{`
		191	`Bigint *c;`
		192	`int k, wa, wb, wc;`
		193	`unsigned long carry, y, z;`
		194	`unsigned long x, xa, xae, xb, xbe, xc, *xc0;`
		195	`#ifdef Pack_32`
		196	`unsigned long z2;`
		197	`#endif`
		198
		199	`if (a->wds < b->wds) {`
		200	`c = a;`
		201	`a = b;`
		202	`b = c;`
		203	`}`
		204	`k = a->k;`
		205	`wa = a->wds;`
		206	`wb = b->wds;`
		207	`wc = wa + wb;`
		208	`if (wc > a->maxwds)`
		209	`k++;`
		210	`c = Balloc(k);`
		211	`for(x = c->x, xa = x + wc; x < xa; x++)`
		212	`*x = 0;`
		213	`xa = a->x;`
		214	`xae = xa + wa;`
		215	`xb = b->x;`
		216	`xbe = xb + wb;`
		217	`xc0 = c->x;`
		218	`#ifdef Pack_32`
		219	`for(; xb < xbe; xb++, xc0++) {`
		220	`if (y = *xb & 0xffff) {`
		221	`x = xa;`
		222	`xc = xc0;`
		223	`carry = 0;`
		224	`do {`
		225	`z = (x & 0xffff) y + (*xc & 0xffff) + carry;`
		226	`carry = z >> 16;`
		227	`z2 = (x++ >> 16) y + (*xc >> 16) + carry;`
		228	`carry = z2 >> 16;`
		229	`Storeinc(xc, z2, z);`
		230	`}`
		231	`while(x < xae);`
		232	`*xc = carry;`
		233	`}`
		234	`if (y = *xb >> 16) {`
		235	`x = xa;`
		236	`xc = xc0;`
		237	`carry = 0;`
		238	`z2 = *xc;`
		239	`do {`
		240	`z = (x & 0xffff) y + (*xc >> 16) + carry;`
		241	`carry = z >> 16;`
		242	`Storeinc(xc, z, z2);`
		243	`z2 = (x++ >> 16) y + (*xc & 0xffff) + carry;`
		244	`carry = z2 >> 16;`
		245	`}`
		246	`while(x < xae);`
		247	`*xc = z2;`
		248	`}`
		249	`}`
		250	`#else`
		251	`for(; xb < xbe; xc0++) {`
		252	`if (y = *xb++) {`
		253	`x = xa;`
		254	`xc = xc0;`
		255	`carry = 0;`
		256	`do {`
		257	`z = x++ y + *xc + carry;`
		258	`carry = z >> 16;`
		259	`*xc++ = z & 0xffff;`
		260	`}`
		261	`while(x < xae);`
		262	`*xc = carry;`
		263	`}`
		264	`}`
		265	`#endif`
		266	`for(xc0 = c->x, xc = xc0 + wc; wc > 0 && !*--xc; --wc) ;`
		267	`c->wds = wc;`
		268	`return c;`
		269	`}`
		270
		271	`static Bigint *p5s;`
		272
		273	`Bigint *`
		274	`_pow5mult(Bigint *b, int k)`
		275	`{`
		276	`Bigint b1, p5, *p51;`
		277	`int i;`
		278	`static int p05[3] = { 5, 25, 125 };`
		279
		280	`if (i = k & 3)`
		281	`b = multadd(b, p05[i-1], 0);`
		282
		283	`if (!(k >>= 2))`
		284	`return b;`
		285	`if (!(p5 = p5s)) {`
		286	`/* first time */`
		287	`p5 = p5s = i2b(625);`
		288	`p5->next = 0;`
		289	`}`
		290	`for(;;) {`
		291	`if (k & 1) {`
		292	`b1 = mult(b, p5);`
		293	`Bfree(b);`
		294	`b = b1;`
		295	`}`
		296	`if (!(k >>= 1))`
		297	`break;`
		298	`if (!(p51 = p5->next)) {`
		299	`p51 = p5->next = mult(p5,p5);`
		300	`p51->next = 0;`
		301	`}`
		302	`p5 = p51;`
		303	`}`
		304	`return b;`
		305	`}`
		306
		307	`Bigint *`
		308	`_lshift(Bigint *b, int k)`
		309	`{`
		310	`int i, k1, n, n1;`
		311	`Bigint *b1;`
		312	`unsigned long x, x1, *xe, z;`
		313
		314	`#ifdef Pack_32`
		315	`n = k >> 5;`
		316	`#else`
		317	`n = k >> 4;`
		318	`#endif`
		319	`k1 = b->k;`
		320	`n1 = n + b->wds + 1;`
		321	`for(i = b->maxwds; n1 > i; i <<= 1)`
		322	`k1++;`
		323	`b1 = Balloc(k1);`
		324	`x1 = b1->x;`
		325	`for(i = 0; i < n; i++)`
		326	`*x1++ = 0;`
		327	`x = b->x;`
		328	`xe = x + b->wds;`
		329	`#ifdef Pack_32`
		330	`if (k &= 0x1f) {`
		331	`k1 = 32 - k;`
		332	`z = 0;`
		333	`do {`
		334	`x1++ = x << k \| z;`
		335	`z = *x++ >> k1;`
		336	`}`
		337	`while(x < xe);`
		338	`if (*x1 = z)`
		339	`++n1;`
		340	`}`
		341	`#else`
		342	`if (k &= 0xf) {`
		343	`k1 = 16 - k;`
		344	`z = 0;`
		345	`do {`
		346	`x1++ = x << k & 0xffff \| z;`
		347	`z = *x++ >> k1;`
		348	`}`
		349	`while(x < xe);`
		350	`if (*x1 = z)`
		351	`++n1;`
		352	`}`
		353	`#endif`
		354	`else do`
		355	`x1++ = x++;`
		356	`while(x < xe);`
		357	`b1->wds = n1 - 1;`
		358	`Bfree(b);`
		359	`return b1;`
		360	`}`
		361
		362	`int`
		363	`_cmp(Bigint a, Bigint b)`
		364	`{`
		365	`unsigned long xa, xa0, xb, xb0;`
		366	`int i, j;`
		367
		368	`i = a->wds;`
		369	`j = b->wds;`
		370	`#ifdef DEBUG`
		371	`if (i > 1 && !a->x[i-1])`
		372	`Bug("cmp called with a->x[a->wds-1] == 0");`
		373	`if (j > 1 && !b->x[j-1])`
		374	`Bug("cmp called with b->x[b->wds-1] == 0");`
		375	`#endif`
		376	`if (i -= j)`
		377	`return i;`
		378	`xa0 = a->x;`
		379	`xa = xa0 + j;`
		380	`xb0 = b->x;`
		381	`xb = xb0 + j;`
		382	`for(;;) {`
		383	`if (--xa != --xb)`
		384	`return xa < xb ? -1 : 1;`
		385	`if (xa <= xa0)`
		386	`break;`
		387	`}`
		388	`return 0;`
		389	`}`
		390
		391	`Bigint *`
		392	`_diff(Bigint a, Bigint b)`
		393	`{`
		394	`Bigint *c;`
		395	`int i, wa, wb;`
		396	`long borrow, y; /* We need signed shifts here. */`
		397	`unsigned long xa, xae, xb, xbe, *xc;`
		398	`#ifdef Pack_32`
		399	`long z;`
		400	`#endif`
		401
		402	`i = cmp(a,b);`
		403	`if (!i) {`
		404	`c = Balloc(0);`
		405	`c->wds = 1;`
		406	`c->x[0] = 0;`
		407	`return c;`
		408	`}`
		409	`if (i < 0) {`
		410	`c = a;`
		411	`a = b;`
		412	`b = c;`
		413	`i = 1;`
		414	`}`
		415	`else`
		416	`i = 0;`
		417	`c = Balloc(a->k);`
		418	`c->sign = i;`
		419	`wa = a->wds;`
		420	`xa = a->x;`
		421	`xae = xa + wa;`
		422	`wb = b->wds;`
		423	`xb = b->x;`
		424	`xbe = xb + wb;`
		425	`xc = c->x;`
		426	`borrow = 0;`
		427	`#ifdef Pack_32`
		428	`do {`
		429	`y = (xa & 0xffff) - (xb & 0xffff) + borrow;`
		430	`borrow = y >> 16;`
		431	`Sign_Extend(borrow, y);`
		432	`z = (xa++ >> 16) - (xb++ >> 16) + borrow;`
		433	`borrow = z >> 16;`
		434	`Sign_Extend(borrow, z);`
		435	`Storeinc(xc, z, y);`
		436	`}`
		437	`while(xb < xbe);`
		438	`while(xa < xae) {`
		439	`y = (*xa & 0xffff) + borrow;`
		440	`borrow = y >> 16;`
		441	`Sign_Extend(borrow, y);`
		442	`z = (*xa++ >> 16) + borrow;`
		443	`borrow = z >> 16;`
		444	`Sign_Extend(borrow, z);`
		445	`Storeinc(xc, z, y);`
		446	`}`
		447	`#else`
		448	`do {`
		449	`y = xa++ - xb++ + borrow;`
		450	`borrow = y >> 16;`
		451	`Sign_Extend(borrow, y);`
		452	`*xc++ = y & 0xffff;`
		453	`}`
		454	`while(xb < xbe);`
		455	`while(xa < xae) {`
		456	`y = *xa++ + borrow;`
		457	`borrow = y >> 16;`
		458	`Sign_Extend(borrow, y);`
		459	`*xc++ = y & 0xffff;`
		460	`}`
		461	`#endif`
		462	`while(!*--xc)`
		463	`wa--;`
		464	`c->wds = wa;`
		465	`return c;`
		466	`}`
		467
		468	`Bigint *`
		469	`_d2b(double darg, int e, int bits)`
		470	`{`
		471	`Bigint *b;`
		472	`int de, i, k;`
		473	`unsigned long *x, y, z;`
		474	`Dul d;`
		475	`#ifdef VAX`
		476	`unsigned long d0, d1;`
		477	`d.d = darg;`
		478	`d0 = word0(d) >> 16 \| word0(d) << 16;`
		479	`d1 = word1(d) >> 16 \| word1(d) << 16;`
		480	`#else`
		481	`d.d = darg;`
		482	`#define d0 word0(d)`
		483	`#define d1 word1(d)`
		484	`#endif`
		485
		486	`#ifdef Pack_32`
		487	`b = Balloc(1);`
		488	`#else`
		489	`b = Balloc(2);`
		490	`#endif`
		491	`x = b->x;`
		492
		493	`z = d0 & Frac_mask;`
		494	`d0 &= 0x7fffffff; /* clear sign bit, which we ignore */`
		495	`#ifdef Sudden_Underflow`
		496	`de = (int)(d0 >> Exp_shift);`
		497	`#ifndef IBM`
		498	`z \|= Exp_msk11;`
		499	`#endif`
		500	`#else`
		501	`if (de = (int)(d0 >> Exp_shift))`
		502	`z \|= Exp_msk1;`
		503	`#endif`
		504	`#ifdef Pack_32`
		505	`if (y = d1) {`
		506	`if (k = lo0bits(&y)) {`
		507	`x[0] = y \| z << 32 - k;`
		508	`z >>= k;`
		509	`}`
		510	`else`
		511	`x[0] = y;`
		512	`i = b->wds = (x[1] = z) ? 2 : 1;`
		513	`}`
		514	`else {`
		515	`#ifdef DEBUG`
		516	`if (!z)`
		517	`Bug("Zero passed to d2b");`
		518	`#endif`
		519	`k = lo0bits(&z);`
		520	`x[0] = z;`
		521	`i = b->wds = 1;`
		522	`k += 32;`
		523	`}`
		524	`#else`
		525	`if (y = d1) {`
		526	`if (k = lo0bits(&y))`
		527	`if (k >= 16) {`
		528	`x[0] = y \| z << 32 - k & 0xffff;`
		529	`x[1] = z >> k - 16 & 0xffff;`
		530	`x[2] = z >> k;`
		531	`i = 2;`
		532	`}`
		533	`else {`
		534	`x[0] = y & 0xffff;`
		535	`x[1] = y >> 16 \| z << 16 - k & 0xffff;`
		536	`x[2] = z >> k & 0xffff;`
		537	`x[3] = z >> k+16;`
		538	`i = 3;`
		539	`}`
		540	`else {`
		541	`x[0] = y & 0xffff;`
		542	`x[1] = y >> 16;`
		543	`x[2] = z & 0xffff;`
		544	`x[3] = z >> 16;`
		545	`i = 3;`
		546	`}`
		547	`}`
		548	`else {`
		549	`#ifdef DEBUG`
		550	`if (!z)`
		551	`Bug("Zero passed to d2b");`
		552	`#endif`
		553	`k = lo0bits(&z);`
		554	`if (k >= 16) {`
		555	`x[0] = z;`
		556	`i = 0;`
		557	`}`
		558	`else {`
		559	`x[0] = z & 0xffff;`
		560	`x[1] = z >> 16;`
		561	`i = 1;`
		562	`}`
		563	`k += 32;`
		564	`}`
		565	`while(!x[i])`
		566	`--i;`
		567	`b->wds = i + 1;`
		568	`#endif`
		569	`#ifndef Sudden_Underflow`
		570	`if (de) {`
		571	`#endif`
		572	`#ifdef IBM`
		573	`*e = (de - Bias - (P-1) << 2) + k;`
		574	`bits = 4P + 8 - k - hi0bits(word0(d) & Frac_mask);`
		575	`#else`
		576	`*e = de - Bias - (P-1) + k;`
		577	`*bits = P - k;`
		578	`#endif`
		579	`#ifndef Sudden_Underflow`
		580	`}`
		581	`else {`
		582	`*e = de - Bias - (P-1) + 1 + k;`
		583	`#ifdef Pack_32`
		584	`bits = 32i - hi0bits(x[i-1]);`
		585	`#else`
		586	`bits = (i+2)16 - hi0bits(x[i]);`
		587	`#endif`
		588	`}`
		589	`#endif`
		590	`return b;`
		591	`}`
		592	`#undef d0`
		593	`#undef d1`

Subversion Repositories planix.SVN

(root)/os/branches/feature_fixcpp/sys/src/ape/lib/ap/stdio/_fconv.c – Rev 2