[oprof-cvs] CVS: oprofile/libdb odb_hash.h,1.3.2.4,1.3.2.5

[Philippe E. <ph...@us...>]

Update of /cvsroot/oprofile/oprofile/libdb
In directory sc8-pr-cvs1:/tmp/cvs-serv31962/libdb

Modified Files:
      Tag: BRANCH_CALLGRAPH
	odb_hash.h 
Log Message:
since hash coding change the file format I prefer to add now a sensible hash for cg, we will change it later only if it cause real problem

Index: odb_hash.h
===================================================================
RCS file: /cvsroot/oprofile/oprofile/libdb/odb_hash.h,v
retrieving revision 1.3.2.4
retrieving revision 1.3.2.5
diff -u -p -d -r1.3.2.4 -r1.3.2.5
--- odb_hash.h	13 Nov 2003 03:27:24 -0000	1.3.2.4
+++ odb_hash.h	13 Nov 2003 05:32:25 -0000	1.3.2.5
@@ -167,17 +167,15 @@ odb_node_t * odb_get_iterator(samples_od
 
 static __inline unsigned int odb_do_hash(samples_odb_t const * hash, odb_key_t value)
 {
-	/* FIXME FIXME: fix hash for 64 bit keys */
 	/* FIXME: better hash for eip value, needs to instrument code
 	 * and do a lot of tests ... */
 	/* trying to combine high order bits his a no-op: inside a binary image
 	 * high order bits don't vary a lot, hash table start with 7 bits mask
-	 * so this hash coding use 15 low order bits of eip, then add one hash
-	 * bits at each grow. Hash table is stored in files avoiding to rebuild
-	 * ing them at profiling re-start so on changing do_hash() change the
-	 * file format
+	 * so this hash coding use bits 3-9 of eip. Hash table is stored in
+	 * files avoiding to rebuilding them at profiling re-start so
+	 * on changing do_hash() change the file format!
 	 */
-	return ((value << 0) ^ (value >> 8)) & hash->hash_mask;
+	return (((value >> 32) ^ (value)) >> 3) & hash->hash_mask;
 }
 
 #ifdef __cplusplus