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author | Igor Pashev <pashev.igor@gmail.com> | 2012-06-24 22:28:35 +0000 |
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committer | Igor Pashev <pashev.igor@gmail.com> | 2012-06-24 22:28:35 +0000 |
commit | 3950ffe2a485479f6561c27364d3d7df5a21d124 (patch) | |
tree | 468c6e14449d1b1e279222ec32f676b0311917d2 /src/lib/libast/include/hashpart.h | |
download | ksh-upstream.tar.gz |
Imported Upstream version 93u+upstream
Diffstat (limited to 'src/lib/libast/include/hashpart.h')
-rw-r--r-- | src/lib/libast/include/hashpart.h | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/src/lib/libast/include/hashpart.h b/src/lib/libast/include/hashpart.h new file mode 100644 index 0000000..ae38262 --- /dev/null +++ b/src/lib/libast/include/hashpart.h @@ -0,0 +1,51 @@ +/*********************************************************************** +* * +* This software is part of the ast package * +* Copyright (c) 1985-2011 AT&T Intellectual Property * +* and is licensed under the * +* Eclipse Public License, Version 1.0 * +* by AT&T Intellectual Property * +* * +* A copy of the License is available at * +* http://www.eclipse.org/org/documents/epl-v10.html * +* (with md5 checksum b35adb5213ca9657e911e9befb180842) * +* * +* Information and Software Systems Research * +* AT&T Research * +* Florham Park NJ * +* * +* Glenn Fowler <gsf@research.att.com> * +* David Korn <dgk@research.att.com> * +* Phong Vo <kpv@research.att.com> * +* * +***********************************************************************/ +#pragma prototyped +/* + * K. P. Vo + * G. S. Fowler + * AT&T Research + * + * ``the best'' combined linear congruent checksum/hash/PRNG + */ + +#ifndef _HASHPART_H +#define _HASHPART_H + +#define HASH_ADD(h) (0x9c39c33dL) + +#if __sparc__ || __sparc || sparc + +#define HASH_A(h,n) ((((h) << 2) - (h)) << (n)) +#define HASH_B(h,n) ((((h) << 4) - (h)) << (n)) +#define HASH_C(h,n) ((HASH_A(h,7) + HASH_B(h,0)) << (n)) +#define HASH_MPY(h) (HASH_C(h,22)+HASH_C(h,10)+HASH_A(h,6)+HASH_A(h,3)+(h)) + +#else + +#define HASH_MPY(h) ((h)*0x63c63cd9L) + +#endif + +#define HASHPART(h,c) (h = HASH_MPY(h) + HASH_ADD(h) + (c)) + +#endif |