From: Roland McGrath <roland@gnu.org>
Date: Fri, 6 Jan 2006 10:37:39 +0000 (+0000)
Subject: * soft-fp/op-common.h (__FP_CLZ): Define using __builtin_clz,
X-Git-Tag: upstream/2.30~15966
X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=0d86378f95994072ccc5db9e993b759208beacfa;p=external%2Fglibc.git

* soft-fp/op-common.h (__FP_CLZ): Define using __builtin_clz,

	__builtin_clzl and __builtin_clzll.
---

diff --git a/ChangeLog b/ChangeLog
index 1b2d996..c0607e4 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,8 @@
+2005-12-04  Joseph S. Myers  <joseph@codesourcery.com>
+
+	* soft-fp/op-common.h (__FP_CLZ): Define using __builtin_clz,
+	__builtin_clzl and __builtin_clzll.
+
 2005-01-05  Mike Frysinger  <vapier@gentoo.org>
 
 	* include/alloca.h (extend_alloca): Fix typoed name 'extern_alloca'.
diff --git a/soft-fp/op-common.h b/soft-fp/op-common.h
index 3abafa1..46162ed 100644
--- a/soft-fp/op-common.h
+++ b/soft-fp/op-common.h
@@ -1,5 +1,5 @@
 /* Software floating-point emulation. Common operations.
-   Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
+   Copyright (C) 1997,1998,1999,2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Richard Henderson (rth@cygnus.com),
 		  Jakub Jelinek (jj@ultra.linux.cz),
@@ -725,40 +725,18 @@ do {									\
 /* Count leading zeros in a word.  */
 
 #ifndef __FP_CLZ
-#if _FP_W_TYPE_SIZE < 64
-/* this is just to shut the compiler up about shifts > word length -- PMM 02/1998 */
-#define __FP_CLZ(r, x)				\
-  do {						\
-    _FP_W_TYPE _t = (x);			\
-    r = _FP_W_TYPE_SIZE - 1;			\
-    if (_t > 0xffff) r -= 16;			\
-    if (_t > 0xffff) _t >>= 16;			\
-    if (_t > 0xff) r -= 8;			\
-    if (_t > 0xff) _t >>= 8;			\
-    if (_t & 0xf0) r -= 4;			\
-    if (_t & 0xf0) _t >>= 4;			\
-    if (_t & 0xc) r -= 2;			\
-    if (_t & 0xc) _t >>= 2;			\
-    if (_t & 0x2) r -= 1;			\
-  } while (0)
-#else /* not _FP_W_TYPE_SIZE < 64 */
-#define __FP_CLZ(r, x)				\
-  do {						\
-    _FP_W_TYPE _t = (x);			\
-    r = _FP_W_TYPE_SIZE - 1;			\
-    if (_t > 0xffffffff) r -= 32;		\
-    if (_t > 0xffffffff) _t >>= 32;		\
-    if (_t > 0xffff) r -= 16;			\
-    if (_t > 0xffff) _t >>= 16;			\
-    if (_t > 0xff) r -= 8;			\
-    if (_t > 0xff) _t >>= 8;			\
-    if (_t & 0xf0) r -= 4;			\
-    if (_t & 0xf0) _t >>= 4;			\
-    if (_t & 0xc) r -= 2;			\
-    if (_t & 0xc) _t >>= 2;			\
-    if (_t & 0x2) r -= 1;			\
+/* GCC 3.4 and later provide the builtins for us.  */
+#define __FP_CLZ(r, x)							      \
+  do {									      \
+    if (sizeof (_FP_W_TYPE) == sizeof (unsigned int))			      \
+      r = __builtin_clz (x);						      \
+    else if (sizeof (_FP_W_TYPE) == sizeof (unsigned long))		      \
+      r = __builtin_clzl (x);						      \
+    else if (sizeof (_FP_W_TYPE) == sizeof (unsigned long long))	      \
+      r = __builtin_clzll (x);						      \
+    else								      \
+      abort ();								      \
   } while (0)
-#endif /* not _FP_W_TYPE_SIZE < 64 */
 #endif /* ndef __FP_CLZ */
 
 #define _FP_DIV_HELP_imm(q, r, n, d)		\