Use bitrotate for hashing.

* gnulib: Update to latest.
* ltdl/m4/gnulib-cache.m4: Import bitrotate module.
* m4/hash.c (m4_hash_string_hash): Use it.

Signed-off-by: Eric Blake <ebb9@byu.net>
(cherry picked from commit 891a0fd44d0666fc0576071ec9866cb2b87490eb)

4 files changed, 11 insertions, 3 deletions

diff --git a/ChangeLog b/ChangeLog
index 49b20f21..70f7bccb 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,10 @@
 2009-06-26  Eric Blake  <ebb9@byu.net>
 
+	Use bitrotate for hashing.
+	* gnulib: Update to latest.
+	* ltdl/m4/gnulib-cache.m4: Import bitrotate module.
+	* m4/hash.c (m4_hash_string_hash): Use it.
+
 	Fix description of limits on diversions.
 	* doc/m4.texinfo (Diversions): Fix grammar.  Be less pessimistic
 	about limitations.
diff --git a/gnulib b/gnulib
-Subproject dcc2f67b6ffab6e9def088ccbf7627edcda4bba
+Subproject 836f3974faad2f3de7bafd46719b77d6632a4c9
diff --git a/ltdl/m4/gnulib-cache.m4 b/ltdl/m4/gnulib-cache.m4
index d72313b0..ec907ec4 100644
--- a/ltdl/m4/gnulib-cache.m4
+++ b/ltdl/m4/gnulib-cache.m4
@@ -15,7 +15,7 @@
 
 
 # Specification in the form of a command-line invocation:
-#   gnulib-tool --import --dir=. --local-dir=local --lib=libgnu --source-base=gnu --m4-base=ltdl/m4 --doc-base=doc --tests-base=tests/gnu --aux-dir=build-aux --with-tests --libtool --macro-prefix=M4 assert autobuild avltree-oset binary-io clean-temp cloexec close-stream closein config-h configmake dirname error execute exit fdl-1.3 fflush filenamecat flexmember fopen fopen-safer freadptr freadseek fseeko gendocs gettext git-version-gen gnumakefile gnupload gpl-3.0 intprops memchr2 memcmp2 memmem mkstemp obstack obstack-printf-posix pipe progname propername quote regex regexprops-generic rename snprintf-posix sprintf-posix stdbool stdlib-safer strnlen strtod strtol tempname unlocked-io vasnprintf-posix verify verror wait-process xalloc xalloc-die xmemdup0 xprintf-posix xstrndup xvasprintf-posix
+#   gnulib-tool --import --dir=. --local-dir=local --lib=libgnu --source-base=gnu --m4-base=ltdl/m4 --doc-base=doc --tests-base=tests/gnu --aux-dir=build-aux --with-tests --libtool --macro-prefix=M4 assert autobuild avltree-oset binary-io bitrotate clean-temp cloexec close-stream closein config-h configmake dirname error execute exit fdl-1.3 fflush filenamecat flexmember fopen fopen-safer freadptr freadseek fseeko gendocs gettext git-version-gen gnumakefile gnupload gpl-3.0 intprops memchr2 memcmp2 memmem mkstemp obstack obstack-printf-posix pipe progname propername quote regex regexprops-generic rename snprintf-posix sprintf-posix stdbool stdlib-safer strnlen strtod strtol tempname unlocked-io vasnprintf-posix verify verror wait-process xalloc xalloc-die xmemdup0 xprintf-posix xstrndup xvasprintf-posix
 
 # Specification in the form of a few gnulib-tool.m4 macro invocations:
 gl_LOCAL_DIR([local])
@@ -24,6 +24,7 @@ gl_MODULES([
   autobuild
   avltree-oset
   binary-io
+  bitrotate
   clean-temp
   cloexec
   close-stream
diff --git a/m4/hash.c b/m4/hash.c
index c07b62d4..a016fbf3 100644
--- a/m4/hash.c
+++ b/m4/hash.c
@@ -1,5 +1,6 @@
 /* GNU m4 -- A simple macro processor
-   Copyright (C) 2001, 2006, 2007, 2008 Free Software Foundation, Inc.
+   Copyright (C) 2001, 2006, 2007, 2008, 2009 Free Software
+   Foundation, Inc.
    Written by Gary V. Vaughan <gary@gnu.org>
 
    This file is part of GNU M4.
@@ -28,6 +29,7 @@
 #include "hash.h"
 #include "m4private.h"
 
+#include "bitrotate.h"
 #include <limits.h>
 
 typedef struct hash_node hash_node;
@@ -650,7 +652,7 @@ m4_hash_string_hash (const void *ptr)
   size_t val = len;
 
   while (len--)
-    val = (val << 7) + (val >> (sizeof val * CHAR_BIT - 7)) + to_uchar (*s++);
+    val = rotl_sz (val, 7) + to_uchar (*s++);
   return val;
 }