Make improvements

third_party/gdtoa/smisc.c

@@ -0,0 +1,192 @@
+#include "third_party/gdtoa/gdtoaimp.h"
+
+/* clang-format off */
+/****************************************************************
+
+The author of this software is David M. Gay.
+
+Copyright (C) 1998, 1999 by Lucent Technologies
+All Rights Reserved
+
+Permission to use, copy, modify, and distribute this software and
+its documentation for any purpose and without fee is hereby
+granted, provided that the above copyright notice appear in all
+copies and that both that the copyright notice and this
+permission notice and warranty disclaimer appear in supporting
+documentation, and that the name of Lucent or any of its entities
+not be used in advertising or publicity pertaining to
+distribution of the software without specific, written prior
+permission.
+
+LUCENT DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE,
+INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS.
+IN NO EVENT SHALL LUCENT OR ANY OF ITS ENTITIES BE LIABLE FOR ANY
+SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER
+IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
+ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF
+THIS SOFTWARE.
+
+****************************************************************/
+
+/* Please send bug reports to David M. Gay (dmg at acm dot org,
+ * with " at " changed at "@" and " dot " changed to ".").	*/
+
+ Bigint *
+s2b
+#ifdef KR_headers
+	(s, nd0, nd, y9, dplen MTa) CONST char *s; int dplen, nd0, nd; ULong y9; MTk
+#else
+	(CONST char *s, int nd0, int nd, ULong y9, int dplen MTd)
+#endif
+{
+	Bigint *b;
+	int i, k;
+	Long x, y;
+
+	x = (nd + 8) / 9;
+	for(k = 0, y = 1; x > y; y <<= 1, k++) ;
+#ifdef Pack_32
+	b = Balloc(k MTa);
+	b->x[0] = y9;
+	b->wds = 1;
+#else
+	b = Balloc(k+1 MTa);
+	b->x[0] = y9 & 0xffff;
+	b->wds = (b->x[1] = y9 >> 16) ? 2 : 1;
+#endif
+
+	i = 9;
+	if (9 < nd0) {
+		s += 9;
+		do b = multadd(b, 10, *s++ - '0' MTa);
+			while(++i < nd0);
+		s += dplen;
+		}
+	else
+		s += dplen + 9;
+	for(; i < nd; i++)
+		b = multadd(b, 10, *s++ - '0' MTa);
+	return b;
+	}
+
+ double
+ratio
+#ifdef KR_headers
+	(a, b) Bigint *a, *b;
+#else
+	(Bigint *a, Bigint *b)
+#endif
+{
+	U da, db;
+	int k, ka, kb;
+
+	dval(&da) = b2d(a, &ka);
+	dval(&db) = b2d(b, &kb);
+	k = ka - kb + ULbits*(a->wds - b->wds);
+#ifdef IBM
+	if (k > 0) {
+		word0(&da) += (k >> 2)*Exp_msk1;
+		if (k &= 3)
+			dval(&da) *= 1 << k;
+		}
+	else {
+		k = -k;
+		word0(&db) += (k >> 2)*Exp_msk1;
+		if (k &= 3)
+			dval(&db) *= 1 << k;
+		}
+#else
+	if (k > 0)
+		word0(&da) += k*Exp_msk1;
+	else {
+		k = -k;
+		word0(&db) += k*Exp_msk1;
+		}
+#endif
+	return dval(&da) / dval(&db);
+	}
+
+#ifdef INFNAN_CHECK
+
+ int
+match
+#ifdef KR_headers
+	(sp, t) char **sp, *t;
+#else
+	(CONST char **sp, char *t)
+#endif
+{
+	int c, d;
+	CONST char *s = *sp;
+
+	while( (d = *t++) !=0) {
+		if ((c = *++s) >= 'A' && c <= 'Z')
+			c += 'a' - 'A';
+		if (c != d)
+			return 0;
+		}
+	*sp = s + 1;
+	return 1;
+	}
+#endif /* INFNAN_CHECK */
+
+ void
+#ifdef KR_headers
+copybits(c, n, b) ULong *c; int n; Bigint *b;
+#else
+copybits(ULong *c, int n, Bigint *b)
+#endif
+{
+	ULong *ce, *x, *xe;
+#ifdef Pack_16
+	int nw, nw1;
+#endif
+
+	ce = c + ((n-1) >> kshift) + 1;
+	x = b->x;
+#ifdef Pack_32
+	xe = x + b->wds;
+	while(x < xe)
+		*c++ = *x++;
+#else
+	nw = b->wds;
+	nw1 = nw & 1;
+	for(xe = x + (nw - nw1); x < xe; x += 2)
+		Storeinc(c, x[1], x[0]);
+	if (nw1)
+		*c++ = *x;
+#endif
+	while(c < ce)
+		*c++ = 0;
+	}
+
+ ULong
+#ifdef KR_headers
+any_on(b, k) Bigint *b; int k;
+#else
+any_on(Bigint *b, int k)
+#endif
+{
+	int n, nwds;
+	ULong *x, *x0, x1, x2;
+
+	x = b->x;
+	nwds = b->wds;
+	n = k >> kshift;
+	if (n > nwds)
+		n = nwds;
+	else if (n < nwds && (k &= kmask)) {
+		x1 = x2 = x[n];
+		x1 >>= k;
+		x1 <<= k;
+		if (x1 != x2)
+			return 1;
+		}
+	x0 = x;
+	x += n;
+	while(x > x0)
+		if (*--x)
+			return 1;
+	return 0;
+	}