Clean up gdtoa code

third_party/gdtoa/misc.c

@@ -1,273 +1,129 @@
+/*-*- mode:c;indent-tabs-mode:t;c-basic-offset:8;tab-width:8;coding:utf-8   -*-│
+│vi: set et ft=c ts=8 tw=8 fenc=utf-8                                       :vi│
+╚──────────────────────────────────────────────────────────────────────────────╝
+│                                                                              │
+│  The author of this software is David M. Gay.                                │
+│  Please send bug reports to David M. Gay <dmg@acm.org>                       │
+│                          or Justine Tunney <jtunney@gmail.com>               │
+│                                                                              │
+│  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.                                                              │
+│                                                                              │
+╚─────────────────────────────────────────────────────────────────────────────*/
 #include "third_party/gdtoa/gdtoa.internal.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 ".").	*/
-
-#ifndef Omit_Private_Memory
-#ifndef PRIVATE_MEM
-#define PRIVATE_MEM 2304
-#endif
-#define PRIVATE_mem ((PRIVATE_MEM+sizeof(double)-1)/sizeof(double))
-static double private_mem[PRIVATE_mem], *pmem_next;
-#endif
-
- static ThInfo TI0;
-
-#ifdef MULTIPLE_THREADS /*{{*/
- static unsigned int maxthreads = 0;
- static ThInfo *TI1;
- static int TI0_used;
-
- void
-set_max_gdtoa_threads(unsigned int n)
-{
-	size_t L;
-
-	if (n > maxthreads) {
-		L = n*sizeof(ThInfo);
-		if (TI1) {
-			TI1 = (ThInfo*)REALLOC(TI1, L);
-			memset(TI1 + maxthreads, 0, (n-maxthreads)*sizeof(ThInfo));
-			}
-		else {
-			TI1 = (ThInfo*)MALLOC(L);
-			if (TI0_used) {
-				memcpy(TI1, &TI0, sizeof(ThInfo));
-				if (n > 1)
-					memset(TI1 + 1, 0, L - sizeof(ThInfo));
-				memset(&TI0, 0, sizeof(ThInfo));
-				}
-			else
-				memset(TI1, 0, L);
-			}
-		maxthreads = n;
-		}
-	}
-
- static ThInfo*
-get_TI(void)
-{
-	unsigned int thno = dtoa_get_threadno();
-	if (thno < maxthreads)
-		return TI1 + thno;
-	if (thno == 0)
-		TI0_used = 1;
-	return &TI0;
-	}
-#define freelist TI->Freelist
-#define p5s TI->P5s
-#else /*}{*/
-#define freelist TI0.Freelist
-#define p5s TI0.P5s
-#endif /*}}*/
+static ThInfo TI0;
 
 Bigint *
-Balloc(int k MTd)
+Balloc(int k)
 {
 	int x;
 	Bigint *rv;
-#ifndef Omit_Private_Memory
-	unsigned int len;
-#endif
-
-        static bool once;
-        if (!once) {
-                pmem_next = private_mem;
-                once = true;
-        }
-
-#ifdef MULTIPLE_THREADS
-	ThInfo *TI;
-
-	if (!(TI = *PTI))
-		*PTI = TI = get_TI();
-	if (TI == &TI0)
-		ACQUIRE_DTOA_LOCK(0);
-#endif
-	/* The k > Kmax case does not need ACQUIRE_DTOA_LOCK(0), */
-	/* but this case seems very unlikely. */
-	if (k <= Kmax && (rv = freelist[k]) !=0) {
-		freelist[k] = rv->next;
-		}
+	if (k <= Kmax && (rv = TI0.Freelist[k]) != 0)
+		TI0.Freelist[k] = rv->next;
 	else {
 		x = 1 << k;
-#ifdef Omit_Private_Memory
-		rv = (Bigint *)MALLOC(sizeof(Bigint) + (x-1)*sizeof(ULong));
-#else
-		len = (sizeof(Bigint) + (x-1)*sizeof(ULong) + sizeof(double) - 1)
-			/sizeof(double);
-		if (k <= Kmax && pmem_next - private_mem + len - PRIVATE_mem <= 0
-#ifdef MULTIPLE_THREADS
-			&& TI == TI1
-#endif
-			) {
-			rv = (Bigint*)pmem_next;
-			pmem_next += len;
-			}
-		else
-			rv = (Bigint*)MALLOC(len*sizeof(double));
-#endif
+		rv = (Bigint *)malloc(sizeof(Bigint) + (x-1)*sizeof(ULong));
 		rv->k = k;
 		rv->maxwds = x;
-		}
-#ifdef MULTIPLE_THREADS
-	if (TI == &TI0)
-		FREE_DTOA_LOCK(0);
-#endif
+	}
 	rv->sign = rv->wds = 0;
 	return rv;
-	}
+}
 
 void
-Bfree(Bigint *v MTd)
+Bfree(Bigint *v)
 {
-#ifdef MULTIPLE_THREADS
-	ThInfo *TI;
-#endif
 	if (v) {
 		if (v->k > Kmax)
-#ifdef FREE
-			FREE((void*)v);
-#else
 			free((void*)v);
-#endif
 		else {
-#ifdef MULTIPLE_THREADS
-			if (!(TI = *PTI))
-				*PTI = TI = get_TI();
-			if (TI == &TI0)
-				ACQUIRE_DTOA_LOCK(0);
-#endif
-			v->next = freelist[v->k];
-			freelist[v->k] = v;
-#ifdef MULTIPLE_THREADS
-			if (TI == &TI0)
-				FREE_DTOA_LOCK(0);
-#endif
-			}
+			v->next = TI0.Freelist[v->k];
+			TI0.Freelist[v->k] = v;
 		}
 	}
+}
 
 Bigint *
-multadd(Bigint *b, int m, int a MTd)	/* multiply by m and add a */
+multadd(Bigint *b, int m, int a)	/* multiply by m and add a */
 {
 	int i, wds;
-#ifdef ULLong
 	ULong *x;
 	ULLong carry, y;
-#else
-	ULong carry, *x, y;
-#ifdef Pack_32
-	ULong xi, z;
-#endif
-#endif
 	Bigint *b1;
-
 	wds = b->wds;
 	x = b->x;
 	i = 0;
 	carry = a;
 	do {
-#ifdef ULLong
 		y = *x * (ULLong)m + carry;
 		carry = y >> 32;
 		*x++ = y & 0xffffffffUL;
-#else
-#ifdef Pack_32
-		xi = *x;
-		y = (xi & 0xffff) * m + carry;
-		z = (xi >> 16) * m + (y >> 16);
-		carry = z >> 16;
-		*x++ = (z << 16) + (y & 0xffff);
-#else
-		y = *x * m + carry;
-		carry = y >> 16;
-		*x++ = y & 0xffff;
-#endif
-#endif
-		}
-		while(++i < wds);
+	}
+	while(++i < wds);
 	if (carry) {
 		if (wds >= b->maxwds) {
-			b1 = Balloc(b->k+1 MTa);
+			b1 = Balloc(b->k+1);
 			Bcopy(b1, b);
-			Bfree(b MTa);
+			Bfree(b);
 			b = b1;
-			}
+		}
 		b->x[wds++] = carry;
 		b->wds = wds;
-		}
-	return b;
 	}
+	return b;
+}
 
 Bigint *
-i2b(int i MTd)
+i2b(int i)
 {
 	Bigint *b;
-
-	b = Balloc(1 MTa);
+	b = Balloc(1);
 	b->x[0] = i;
 	b->wds = 1;
 	return b;
-	}
+}
 
 Bigint *
-mult(Bigint *a, Bigint *b MTd)
+mult(Bigint *a, Bigint *b)
 {
 	Bigint *c;
 	int k, wa, wb, wc;
 	ULong *x, *xa, *xae, *xb, *xbe, *xc, *xc0;
 	ULong y;
-#ifdef ULLong
 	ULLong carry, z;
-#else
-	ULong carry, z;
-#ifdef Pack_32
-	ULong z2;
-#endif
-#endif
-
 	if (a->wds < b->wds) {
 		c = a;
 		a = b;
 		b = c;
-		}
+	}
 	k = a->k;
 	wa = a->wds;
 	wb = b->wds;
 	wc = wa + wb;
 	if (wc > a->maxwds)
 		k++;
-	c = Balloc(k MTa);
+	c = Balloc(k);
 	for(x = c->x, xa = x + wc; x < xa; x++)
 		*x = 0;
 	xa = a->x;
@@ -275,7 +131,6 @@ mult(Bigint *a, Bigint *b MTd)
 	xb = b->x;
 	xbe = xb + wb;
 	xc0 = c->x;
-#ifdef ULLong
 	for(; xb < xbe; xc0++) {
 		if ( (y = *xb++) !=0) {
 			x = xa;
@@ -285,188 +140,89 @@ mult(Bigint *a, Bigint *b MTd)
 				z = *x++ * (ULLong)y + *xc + carry;
 				carry = z >> 32;
 				*xc++ = z & 0xffffffffUL;
-				}
-				while(x < xae);
+			}
+			while(x < xae);
 			*xc = carry;
-			}
 		}
-#else
-#ifdef Pack_32
-	for(; xb < xbe; xb++, xc0++) {
-		if ( (y = *xb & 0xffff) !=0) {
-			x = xa;
-			xc = xc0;
-			carry = 0;
-			do {
-				z = (*x & 0xffff) * y + (*xc & 0xffff) + carry;
-				carry = z >> 16;
-				z2 = (*x++ >> 16) * y + (*xc >> 16) + carry;
-				carry = z2 >> 16;
-				Storeinc(xc, z2, z);
-				}
-				while(x < xae);
-			*xc = carry;
-			}
-		if ( (y = *xb >> 16) !=0) {
-			x = xa;
-			xc = xc0;
-			carry = 0;
-			z2 = *xc;
-			do {
-				z = (*x & 0xffff) * y + (*xc >> 16) + carry;
-				carry = z >> 16;
-				Storeinc(xc, z, z2);
-				z2 = (*x++ >> 16) * y + (*xc & 0xffff) + carry;
-				carry = z2 >> 16;
-				}
-				while(x < xae);
-			*xc = z2;
-			}
-		}
-#else
-	for(; xb < xbe; xc0++) {
-		if ( (y = *xb++) !=0) {
-			x = xa;
-			xc = xc0;
-			carry = 0;
-			do {
-				z = *x++ * y + *xc + carry;
-				carry = z >> 16;
-				*xc++ = z & 0xffff;
-				}
-				while(x < xae);
-			*xc = carry;
-			}
-		}
-#endif
-#endif
+	}
 	for(xc0 = c->x, xc = xc0 + wc; wc > 0 && !*--xc; --wc) ;
 	c->wds = wc;
 	return c;
-	}
+}
 
 Bigint *
-pow5mult(Bigint *b, int k MTd)
+pow5mult(Bigint *b, int k)
 {
 	Bigint *b1, *p5, *p51;
-#ifdef MULTIPLE_THREADS
-	ThInfo *TI;
-#endif
 	int i;
 	static const int p05[3] = { 5, 25, 125 };
-
 	if ( (i = k & 3) !=0)
-		b = multadd(b, p05[i-1], 0 MTa);
-
+		b = multadd(b, p05[i-1], 0);
 	if (!(k >>= 2))
 		return b;
-#ifdef  MULTIPLE_THREADS
-	if (!(TI = *PTI))
-		*PTI = TI = get_TI();
-#endif
-	if ((p5 = p5s) == 0) {
+	if ((p5 = TI0.P5s) == 0) {
 		/* first time */
-#ifdef MULTIPLE_THREADS
-		if (!(TI = *PTI))
-			*PTI = TI = get_TI();
-		if (TI == &TI0)
-			ACQUIRE_DTOA_LOCK(1);
-		if (!(p5 = p5s)) {
-			p5 = p5s = i2b(625 MTa);
-			p5->next = 0;
-			}
-		if (TI == &TI0)
-			FREE_DTOA_LOCK(1);
-#else
-		p5 = p5s = i2b(625);
+		p5 = TI0.P5s = i2b(625);
 		p5->next = 0;
-#endif
-		}
+	}
 	for(;;) {
 		if (k & 1) {
-			b1 = mult(b, p5 MTa);
-			Bfree(b MTa);
+			b1 = mult(b, p5);
+			Bfree(b);
 			b = b1;
-			}
+		}
 		if (!(k >>= 1))
 			break;
 		if ((p51 = p5->next) == 0) {
-#ifdef MULTIPLE_THREADS
-			if (!TI && !(TI = *PTI))
-				*PTI = TI = get_TI();
-			if (TI == &TI0)
-				ACQUIRE_DTOA_LOCK(1);
-			if (!(p51 = p5->next)) {
-				p51 = p5->next = mult(p5,p5 MTa);
-				p51->next = 0;
-				}
-			if (TI == &TI0)
-				FREE_DTOA_LOCK(1);
-#else
-			p51 = p5->next = mult(p5,p5 MTa);
+			p51 = p5->next = mult(p5,p5);
 			p51->next = 0;
-#endif
-			}
-		p5 = p51;
 		}
-	return b;
+		p5 = p51;
 	}
+	return b;
+}
 
 Bigint *
-lshift(Bigint *b, int k MTd)
+lshift(Bigint *b, int k)
 {
 	int i, k1, n, n1;
 	Bigint *b1;
 	ULong *x, *x1, *xe, z;
-
 	n = k >> kshift;
 	k1 = b->k;
 	n1 = n + b->wds + 1;
 	for(i = b->maxwds; n1 > i; i <<= 1)
 		k1++;
-	b1 = Balloc(k1 MTa);
+	b1 = Balloc(k1);
 	x1 = b1->x;
 	for(i = 0; i < n; i++)
 		*x1++ = 0;
 	x = b->x;
 	xe = x + b->wds;
 	if (k &= kmask) {
-#ifdef Pack_32
 		k1 = 32 - k;
 		z = 0;
 		do {
 			*x1++ = *x << k | z;
 			z = *x++ >> k1;
-			}
-			while(x < xe);
+		}
+		while(x < xe);
 		if ((*x1 = z) !=0)
 			++n1;
-#else
-		k1 = 16 - k;
-		z = 0;
-		do {
-			*x1++ = *x << k  & 0xffff | z;
-			z = *x++ >> k1;
-			}
-			while(x < xe);
-		if (*x1 = z)
-			++n1;
-#endif
-		}
+	}
 	else do
-		*x1++ = *x++;
+		     *x1++ = *x++;
 		while(x < xe);
 	b1->wds = n1 - 1;
-	Bfree(b MTa);
+	Bfree(b);
 	return b1;
-	}
+}
 
 int
 cmp(Bigint *a, Bigint *b)
 {
 	ULong *xa, *xa0, *xb, *xb0;
 	int i, j;
-
 	i = a->wds;
 	j = b->wds;
 #ifdef DEBUG
@@ -486,41 +242,33 @@ cmp(Bigint *a, Bigint *b)
 			return *xa < *xb ? -1 : 1;
 		if (xa <= xa0)
 			break;
-		}
-	return 0;
 	}
+	return 0;
+}
 
 Bigint *
-diff(Bigint *a, Bigint *b MTd)
+diff(Bigint *a, Bigint *b)
 {
 	Bigint *c;
 	int i, wa, wb;
 	ULong *xa, *xae, *xb, *xbe, *xc;
-#ifdef ULLong
 	ULLong borrow, y;
-#else
-	ULong borrow, y;
-#ifdef Pack_32
-	ULong z;
-#endif
-#endif
-
 	i = cmp(a,b);
 	if (!i) {
-		c = Balloc(0 MTa);
+		c = Balloc(0);
 		c->wds = 1;
 		c->x[0] = 0;
 		return c;
-		}
+	}
 	if (i < 0) {
 		c = a;
 		a = b;
 		b = c;
 		i = 1;
-		}
+	}
 	else
 		i = 0;
-	c = Balloc(a->k MTa);
+	c = Balloc(a->k);
 	c->sign = i;
 	wa = a->wds;
 	xa = a->x;
@@ -530,54 +278,22 @@ diff(Bigint *a, Bigint *b MTd)
 	xbe = xb + wb;
 	xc = c->x;
 	borrow = 0;
-#ifdef ULLong
 	do {
 		y = (ULLong)*xa++ - *xb++ - borrow;
 		borrow = y >> 32 & 1UL;
 		*xc++ = y & 0xffffffffUL;
-		}
-		while(xb < xbe);
+	}
+	while(xb < xbe);
 	while(xa < xae) {
 		y = *xa++ - borrow;
 		borrow = y >> 32 & 1UL;
 		*xc++ = y & 0xffffffffUL;
-		}
-#else
-#ifdef Pack_32
-	do {
-		y = (*xa & 0xffff) - (*xb & 0xffff) - borrow;
-		borrow = (y & 0x10000) >> 16;
-		z = (*xa++ >> 16) - (*xb++ >> 16) - borrow;
-		borrow = (z & 0x10000) >> 16;
-		Storeinc(xc, z, y);
-		}
-		while(xb < xbe);
-	while(xa < xae) {
-		y = (*xa & 0xffff) - borrow;
-		borrow = (y & 0x10000) >> 16;
-		z = (*xa++ >> 16) - borrow;
-		borrow = (z & 0x10000) >> 16;
-		Storeinc(xc, z, y);
-		}
-#else
-	do {
-		y = *xa++ - *xb++ - borrow;
-		borrow = (y & 0x10000) >> 16;
-		*xc++ = y & 0xffff;
-		}
-		while(xb < xbe);
-	while(xa < xae) {
-		y = *xa++ - borrow;
-		borrow = (y & 0x10000) >> 16;
-		*xc++ = y & 0xffff;
-		}
-#endif
-#endif
+	}
 	while(!*--xc)
 		wa--;
 	c->wds = wa;
 	return c;
-	}
+}
 
 double
 b2d(Bigint *a, int *e)
@@ -585,13 +301,6 @@ b2d(Bigint *a, int *e)
 	ULong *xa, *xa0, w, y, z;
 	int k;
 	U d;
-#ifdef VAX
-	ULong d0, d1;
-#else
-#define d0 word0(&d)
-#define d1 word1(&d)
-#endif
-
 	xa0 = a->x;
 	xa = xa0 + a->wds;
 	y = *--xa;
@@ -600,225 +309,76 @@ b2d(Bigint *a, int *e)
 #endif
 	k = hi0bits(y);
 	*e = 32 - k;
-#ifdef Pack_32
 	if (k < Ebits) {
-		d0 = Exp_1 | y >> (Ebits - k);
+		word0(&d) = Exp_1 | y >> (Ebits - k);
 		w = xa > xa0 ? *--xa : 0;
-		d1 = y << ((32-Ebits) + k) | w >> (Ebits - k);
+		word1(&d) = y << ((32-Ebits) + k) | w >> (Ebits - k);
 		goto ret_d;
-		}
+	}
 	z = xa > xa0 ? *--xa : 0;
 	if (k -= Ebits) {
-		d0 = Exp_1 | y << k | z >> (32 - k);
+		word0(&d) = Exp_1 | y << k | z >> (32 - k);
 		y = xa > xa0 ? *--xa : 0;
-		d1 = z << k | y >> (32 - k);
-		}
-	else {
-		d0 = Exp_1 | y;
-		d1 = z;
-		}
-#else
-	if (k < Ebits + 16) {
-		z = xa > xa0 ? *--xa : 0;
-		d0 = Exp_1 | y << k - Ebits | z >> Ebits + 16 - k;
-		w = xa > xa0 ? *--xa : 0;
-		y = xa > xa0 ? *--xa : 0;
-		d1 = z << k + 16 - Ebits | w << k - Ebits | y >> 16 + Ebits - k;
-		goto ret_d;
-		}
-	z = xa > xa0 ? *--xa : 0;
-	w = xa > xa0 ? *--xa : 0;
-	k -= Ebits + 16;
-	d0 = Exp_1 | y << k + 16 | z << k | w >> 16 - k;
-	y = xa > xa0 ? *--xa : 0;
-	d1 = w << k + 16 | y << k;
-#endif
- ret_d:
-#ifdef VAX
-	word0(&d) = d0 >> 16 | d0 << 16;
-	word1(&d) = d1 >> 16 | d1 << 16;
-#endif
-	return dval(&d);
+		word1(&d) = z << k | y >> (32 - k);
 	}
-#undef d0
-#undef d1
+	else {
+		word0(&d) = Exp_1 | y;
+		word1(&d) = z;
+	}
+ret_d:
+	return dval(&d);
+}
 
 Bigint *
-d2b(double dd, int *e, int *bits MTd)
+d2b(double dd, int *e, int *bits)
 {
 	Bigint *b;
 	U d;
-#ifndef Sudden_Underflow
 	int i;
-#endif
 	int de, k;
 	ULong *x, y, z;
-#ifdef VAX
-	ULong d0, d1;
-#else
-#define d0 word0(&d)
-#define d1 word1(&d)
-#endif
 	d.d = dd;
-#ifdef VAX
-	d0 = word0(&d) >> 16 | word0(&d) << 16;
-	d1 = word1(&d) >> 16 | word1(&d) << 16;
-#endif
-
-#ifdef Pack_32
-	b = Balloc(1 MTa);
-#else
-	b = Balloc(2 MTa);
-#endif
+	b = Balloc(1);
 	x = b->x;
-
-	z = d0 & Frac_mask;
-	d0 &= 0x7fffffff;	/* clear sign bit, which we ignore */
-#ifdef Sudden_Underflow
-	de = (int)(d0 >> Exp_shift);
-#ifndef IBM
-	z |= Exp_msk11;
-#endif
-#else
-	if ( (de = (int)(d0 >> Exp_shift)) !=0)
+	z = word0(&d) & Frac_mask;
+	word0(&d) &= 0x7fffffff;	/* clear sign bit, which we ignore */
+	if ( (de = (int)(word0(&d) >> Exp_shift)) !=0)
 		z |= Exp_msk1;
-#endif
-#ifdef Pack_32
-	if ( (y = d1) !=0) {
+	if ( (y = word1(&d)) !=0) {
 		if ( (k = lo0bits(&y)) !=0) {
 			x[0] = y | z << (32 - k);
 			z >>= k;
-			}
+		}
 		else
 			x[0] = y;
-#ifndef Sudden_Underflow
-		i =
-#endif
-		     b->wds = (x[1] = z) !=0 ? 2 : 1;
-		}
+		i = b->wds = (x[1] = z) !=0 ? 2 : 1;
+	}
 	else {
 		k = lo0bits(&z);
 		x[0] = z;
-#ifndef Sudden_Underflow
-		i =
-#endif
-		    b->wds = 1;
+		i = b->wds = 1;
 		k += 32;
-		}
-#else
-	if ( (y = d1) !=0) {
-		if ( (k = lo0bits(&y)) !=0)
-			if (k >= 16) {
-				x[0] = y | z << 32 - k & 0xffff;
-				x[1] = z >> k - 16 & 0xffff;
-				x[2] = z >> k;
-				i = 2;
-				}
-			else {
-				x[0] = y & 0xffff;
-				x[1] = y >> 16 | z << 16 - k & 0xffff;
-				x[2] = z >> k & 0xffff;
-				x[3] = z >> k+16;
-				i = 3;
-				}
-		else {
-			x[0] = y & 0xffff;
-			x[1] = y >> 16;
-			x[2] = z & 0xffff;
-			x[3] = z >> 16;
-			i = 3;
-			}
-		}
-	else {
-#ifdef DEBUG
-		if (!z)
-			Bug("Zero passed to d2b");
-#endif
-		k = lo0bits(&z);
-		if (k >= 16) {
-			x[0] = z;
-			i = 0;
-			}
-		else {
-			x[0] = z & 0xffff;
-			x[1] = z >> 16;
-			i = 1;
-			}
-		k += 32;
-		}
-	while(!x[i])
-		--i;
-	b->wds = i + 1;
-#endif
-#ifndef Sudden_Underflow
+	}
 	if (de) {
-#endif
-#ifdef IBM
-		*e = (de - Bias - (P-1) << 2) + k;
-		*bits = 4*P + 8 - k - hi0bits(word0(&d) & Frac_mask);
-#else
 		*e = de - Bias - (P-1) + k;
 		*bits = P - k;
-#endif
-#ifndef Sudden_Underflow
-		}
+	}
 	else {
 		*e = de - Bias - (P-1) + 1 + k;
-#ifdef Pack_32
 		*bits = 32*i - hi0bits(x[i-1]);
-#else
-		*bits = (i+2)*16 - hi0bits(x[i]);
-#endif
-		}
-#endif
+	}
 	return b;
-	}
-#undef d0
-#undef d1
+}
 
-CONST double
-#ifdef IEEE_Arith
+const double
 bigtens[] = { 1e16, 1e32, 1e64, 1e128, 1e256 };
-CONST double tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128, 1e-256
-		};
-#else
-#ifdef IBM
-bigtens[] = { 1e16, 1e32, 1e64 };
-CONST double tinytens[] = { 1e-16, 1e-32, 1e-64 };
-#else
-bigtens[] = { 1e16, 1e32 };
-CONST double tinytens[] = { 1e-16, 1e-32 };
-#endif
-#endif
 
-CONST double
+const double
+tinytens[] = { 1e-16, 1e-32, 1e-64, 1e-128, 1e-256 };
+
+const double
 tens[] = {
-		1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
-		1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
-		1e20, 1e21, 1e22
-#ifdef VAX
-		, 1e23, 1e24
-#endif
-		};
-
-char *
-__gdtoa_strcp(char *a, CONST char *b)
-{
-	while((*a = *b++))
-		a++;
-	return a;
-	}
-
-#ifdef NO_STRING_H
-
-Char *
-__gdtoa_memcpy(void *a1, void *b1, size_t len)
-{
-	char *a = (char*)a1, *ae = a + len;
-	char *b = (char*)b1, *a0 = a;
-	while(a < ae)
-		*a++ = *b++;
-	return a0;
-	}
-
-#endif /* NO_STRING_H */
+	1e0, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
+	1e10, 1e11, 1e12, 1e13, 1e14, 1e15, 1e16, 1e17, 1e18, 1e19,
+	1e20, 1e21, 1e22
+};