Optimize generic ELF hash function a bit more

2 files changed, 9 insertions, 1 deletions

diff --git a/ChangeLog b/ChangeLog
index 73e9911..93adebd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2011-12-10  Ulrich Drepper  <drepper@gmail.com>
+
+	* sysdeps/generic/dl-hash.h (_dl_elf_hash): Lift one operation out of
+	the inner loop.
+
 2011-12-06  Andreas Schwab  <schwab@linux-m68k.org>
 
 	[BZ #13472]
diff --git a/sysdeps/generic/dl-hash.h b/sysdeps/generic/dl-hash.h
index 28312ca..e0db00e 100644
--- a/sysdeps/generic/dl-hash.h
+++ b/sysdeps/generic/dl-hash.h
@@ -60,9 +60,12 @@ _dl_elf_hash (const char *name_arg)
 			 But the following is equivalent and a lot
 			 faster, especially on modern processors.  */
 
-		      hash ^= hi;
 		      hash ^= hi >> 24;
 		    }
+
+		  /* Second part of the modified formula.  This
+		     operation can be lifted outside the loop.  */
+		  hash &= 0x0fffffff;
 		}
 	    }
 	}