1 files changed, 105 insertions, 0 deletions
diff --git a/StdLib/LibC/gdtoa/sum.c b/StdLib/LibC/gdtoa/sum.c
new file mode 100644
index 0000000000..850c1f0134
--- /dev/null
+++ b/StdLib/LibC/gdtoa/sum.c
@@ -0,0 +1,105 @@
+/* $NetBSD: sum.c,v 1.1.1.1.14.1 2008/04/08 21:10:55 jdc Exp $ */
+
+/****************************************************************
+
+The author of this software is David M. Gay.
+
+Copyright (C) 1998 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 ".").  */
+#include  <LibConfig.h>
+
+#include "gdtoaimp.h"
+
+ Bigint *
+#ifdef KR_headers
+sum(a, b) Bigint *a; Bigint *b;
+#else
+sum(Bigint *a, Bigint *b)
+#endif
+{
+  Bigint *c;
+  ULong carry, *xc, *xa, *xb, *xe, y;
+#ifdef Pack_32
+  ULong z;
+#endif
+
+  if (a->wds < b->wds) {
+    c = b; b = a; a = c;
+    }
+  c = Balloc(a->k);
+  if (c == NULL)
+    return NULL;
+  c->wds = a->wds;
+  carry = 0;
+  xa = a->x;
+  xb = b->x;
+  xc = c->x;
+  xe = xc + b->wds;
+#ifdef Pack_32
+  do {
+    y = (*xa & 0xffff) + (*xb & 0xffff) + carry;
+    carry = (y & 0x10000) >> 16;
+    z = (*xa++ >> 16) + (*xb++ >> 16) + carry;
+    carry = (z & 0x10000) >> 16;
+    Storeinc(xc, z, y);
+    }
+    while(xc < xe);
+  xe += a->wds - b->wds;
+  while(xc < xe) {
+    y = (*xa & 0xffff) + carry;
+    carry = (y & 0x10000) >> 16;
+    z = (*xa++ >> 16) + carry;
+    carry = (z & 0x10000) >> 16;
+    Storeinc(xc, z, y);
+    }
+#else
+  do {
+    y = *xa++ + *xb++ + carry;
+    carry = (y & 0x10000) >> 16;
+    *xc++ = y & 0xffff;
+    }
+    while(xc < xe);
+  xe += a->wds - b->wds;
+  while(xc < xe) {
+    y = *xa++ + carry;
+    carry = (y & 0x10000) >> 16;
+    *xc++ = y & 0xffff;
+    }
+#endif
+  if (carry) {
+    if (c->wds == c->maxwds) {
+      b = Balloc(c->k + 1);
+      if (b == NULL)
+        return NULL;
+      Bcopy(b, c);
+      Bfree(c);
+      c = b;
+      }
+    c->x[c->wds++] = 1;
+    }
+  return c;
+  }