Add hurd/math.h.

2008-12-04  Neal H. Walfield  <neal@gnu.org>

	* bits/ia32/math.h: New file.
	* math.h: New file.
	* headers.m4: Link sysroot/include/hurd/math.h to hurd/math.h and
	sysroot/include/hurd/bits/math.h to hurd/bits/${arch}/math.h.

4 files changed, 202 insertions, 0 deletions

diff --git a/hurd/ChangeLog b/hurd/ChangeLog
index 5af636a..28d4f3c 100644
--- a/hurd/ChangeLog
+++ b/hurd/ChangeLog
@@ -1,5 +1,12 @@
 2008-12-04  Neal H. Walfield  <neal@gnu.org>
 
+	* bits/ia32/math.h: New file.
+	* math.h: New file.
+	* headers.m4: Link sysroot/include/hurd/math.h to hurd/math.h and
+	sysroot/include/hurd/bits/math.h to hurd/bits/${arch}/math.h.
+
+2008-12-04  Neal H. Walfield  <neal@gnu.org>
+
 	* mutex.h: Don't include <atomic.h>.
 	(ss_mutex_lock): Rewrite to use gcc's __sync functions.  Add
 	asserts.
diff --git a/hurd/bits/ia32/math.h b/hurd/bits/ia32/math.h
new file mode 100644
index 0000000..c1e6479
--- /dev/null
+++ b/hurd/bits/ia32/math.h
@@ -0,0 +1,54 @@
+/* hurd/math.h - Public interface to Hurd mathematical support functions.
+   Copyright (C) 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
+   Written by Marcus Brinkmann <marcus@gnu.org>.
+
+   This file is part of the GNU Hurd.
+ 
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License
+   as published by the Free Software Foundation; either version 2.1 of
+   the License, or (at your option) any later version.
+ 
+   The GNU Hurd is distributed in the hope that it will be
+   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+ 
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU L4 library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+   02111-1307, USA.  */
+
+#ifndef _HURD_BITS_MATH_H
+#define _HURD_BITS_MATH_H
+
+#include <stdint.h>
+
+/* Calculate the MSB set in DATA.  DATA is not 0.  */
+static inline uintptr_t
+__VG_msb (uintptr_t data)
+{
+  uintptr_t msb;
+
+  __asm__ ("bsr %[data], %[msb]"
+	   : [msb] "=r" (msb)
+	   : [data] "rm" (data));
+
+  return msb + 1;
+}
+
+
+/* Calculate the LSB set in DATA.  DATA is not 0.  */
+static inline uintptr_t
+__VG_lsb (uintptr_t data)
+{
+  uintptr_t lsb;
+
+  __asm__ ("bsf %[data], %[lsb]"
+	   : [lsb] "=r" (lsb)
+	   : [data] "rm" (data));
+
+  return lsb + 1;
+}
+
+#endif
diff --git a/hurd/headers.m4 b/hurd/headers.m4
index b1e073c..7708aea 100644
--- a/hurd/headers.m4
+++ b/hurd/headers.m4
@@ -27,4 +27,6 @@ AC_CONFIG_LINKS([sysroot/include/hurd/stddef.h:hurd/stddef.h
 		 sysroot/include/hurd/rmutex.h:hurd/rmutex.h
 		 sysroot/include/hurd/futex.h:hurd/futex.h
 		 sysroot/include/hurd/error.h:hurd/error.h
+		 sysroot/include/hurd/math.h:hurd/math.h
+		 sysroot/include/hurd/bits/math.h:hurd/bits/${arch}/math.h
 		])
diff --git a/hurd/math.h b/hurd/math.h
new file mode 100644
index 0000000..e9e66bb
--- /dev/null
+++ b/hurd/math.h
@@ -0,0 +1,139 @@
+/* l4/math.h - Public interface to Hurd mathematical support functions.
+   Copyright (C) 2003, 2004, 2007, 2008 Free Software Foundation, Inc.
+   Written by Marcus Brinkmann <marcus@gnu.org>.
+
+   This file is part of the GNU Hurd.
+ 
+   The GNU Hurd is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public License
+   as published by the Free Software Foundation; either version 2.1 of
+   the License, or (at your option) any later version.
+ 
+   The GNU Hurd is distributed in the hope that it will be
+   useful, but WITHOUT ANY WARRANTY; without even the implied warranty
+   of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU Lesser General Public License for more details.
+ 
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU L4 library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+   02111-1307, USA.  */
+
+#ifndef _HURD_MATH_H
+#define _HURD_MATH_H
+
+#include <stdint.h>
+#include <bits/wordsize.h>
+#include <hurd/bits/math.h>
+
+/* Return 0 if DATA is 0, or the bit number of the most significant
+   bit set in DATA.  The least significant bit is 1, the most
+   significant bit 32 resp. 64.  */
+static inline uintptr_t
+vg_msb (uintptr_t data)
+{
+  if (__builtin_constant_p (data))
+    {
+#define __VG_MSB_TRY(b) else if (data < (1 << (b))) return (b)
+#define __VG_MSB_IS(b) else return (b)
+
+      if (!data)
+	return 0;
+      __VG_MSB_TRY(1); __VG_MSB_TRY(2); __VG_MSB_TRY(3); __VG_MSB_TRY(4);
+      __VG_MSB_TRY(5); __VG_MSB_TRY(6); __VG_MSB_TRY(7); __VG_MSB_TRY(8);
+      __VG_MSB_TRY(9); __VG_MSB_TRY(10); __VG_MSB_TRY(11); __VG_MSB_TRY(12);
+      __VG_MSB_TRY(13); __VG_MSB_TRY(14); __VG_MSB_TRY(15); __VG_MSB_TRY(16);
+      __VG_MSB_TRY(17); __VG_MSB_TRY(18); __VG_MSB_TRY(19); __VG_MSB_TRY(20);
+      __VG_MSB_TRY(21); __VG_MSB_TRY(22); __VG_MSB_TRY(23); __VG_MSB_TRY(24);
+      __VG_MSB_TRY(25); __VG_MSB_TRY(26); __VG_MSB_TRY(27); __VG_MSB_TRY(28);
+      __VG_MSB_TRY(29); __VG_MSB_TRY(30); __VG_MSB_TRY(31);
+#if __WORDSIZE == 32
+      __VG_MSB_IS(32);
+#else
+      __VG_MSB_TRY(32); __VG_MSB_TRY(33); __VG_MSB_TRY(34); __VG_MSB_TRY(35);
+      __VG_MSB_TRY(36); __VG_MSB_TRY(37); __VG_MSB_TRY(38); __VG_MSB_TRY(39);
+      __VG_MSB_TRY(40); __VG_MSB_TRY(41); __VG_MSB_TRY(42); __VG_MSB_TRY(43);
+      __VG_MSB_TRY(44); __VG_MSB_TRY(45); __VG_MSB_TRY(46); __VG_MSB_TRY(47);
+      __VG_MSB_TRY(48); __VG_MSB_TRY(49); __VG_MSB_TRY(50); __VG_MSB_TRY(51);
+      __VG_MSB_TRY(52); __VG_MSB_TRY(53); __VG_MSB_TRY(54); __VG_MSB_TRY(55);
+      __VG_MSB_TRY(56); __VG_MSB_TRY(57); __VG_MSB_TRY(58); __VG_MSB_TRY(59);
+      __VG_MSB_TRY(60); __VG_MSB_TRY(61); __VG_MSB_TRY(62); __VG_MSB_TRY(63);
+      __VG_MSB_IS(64);
+#endif
+    }
+
+  if (__builtin_expect (data != 0, 1))
+    return __VG_msb (data);
+  else
+    return 0;
+}
+
+static inline uintptr_t
+vg_msb64 (uint64_t data)
+{
+#if __WORDSIZE == 64
+  return vg_msb (data);
+#else
+  int d = vg_msb (data >> 32);
+  if (d)
+    return d + 32;
+  return vg_msb (data);
+#endif
+}
+
+/* Return 0 if DATA is 0, or the bit number of the least significant
+   bit set in DATA.  The least significant bit is 1, the most
+   significant bit 32 resp. 64.  */
+static inline uintptr_t
+vg_lsb (uintptr_t data)
+{
+  if (__builtin_constant_p (data))
+    {
+#define __VG_LSB_TRY(b) else if (data >= (1 << (b - 1))) return (b)
+#define __VG_LSB_IS(b) else return (b)
+
+      if (!data)
+	return 0;
+#if __WORDSIZE == 64
+      __VG_LSB_TRY(64); __VG_LSB_TRY(63); __VG_LSB_TRY(62); __VG_LSB_TRY(61);
+      __VG_LSB_TRY(60); __VG_LSB_TRY(59); __VG_LSB_TRY(58); __VG_LSB_TRY(57);
+      __VG_LSB_TRY(56); __VG_LSB_TRY(55); __VG_LSB_TRY(54); __VG_LSB_TRY(53);
+      __VG_LSB_TRY(52); __VG_LSB_TRY(51); __VG_LSB_TRY(50); __VG_LSB_TRY(49);
+      __VG_LSB_TRY(48); __VG_LSB_TRY(47); __VG_LSB_TRY(46); __VG_LSB_TRY(45);
+      __VG_LSB_TRY(44); __VG_LSB_TRY(43); __VG_LSB_TRY(42); __VG_LSB_TRY(41);
+      __VG_LSB_TRY(40); __VG_LSB_TRY(39); __VG_LSB_TRY(38); __VG_LSB_TRY(37);
+      __VG_LSB_TRY(36); __VG_LSB_TRY(35); __VG_LSB_TRY(34); __VG_LSB_TRY(33);
+#endif
+      __VG_LSB_TRY(32); __VG_LSB_TRY(31); __VG_LSB_TRY(30); __VG_LSB_TRY(29);
+      __VG_LSB_TRY(28); __VG_LSB_TRY(27); __VG_LSB_TRY(26); __VG_LSB_TRY(25);
+      __VG_LSB_TRY(24); __VG_LSB_TRY(23); __VG_LSB_TRY(22); __VG_LSB_TRY(21);
+      __VG_LSB_TRY(20); __VG_LSB_TRY(19); __VG_LSB_TRY(18); __VG_LSB_TRY(17);
+      __VG_LSB_TRY(16); __VG_LSB_TRY(15); __VG_LSB_TRY(14); __VG_LSB_TRY(13);
+      __VG_LSB_TRY(12); __VG_LSB_TRY(11); __VG_LSB_TRY(10); __VG_LSB_TRY(9);
+      __VG_LSB_TRY(8); __VG_LSB_TRY(7); __VG_LSB_TRY(6); __VG_LSB_TRY(5);
+      __VG_LSB_TRY(4); __VG_LSB_TRY(3); __VG_LSB_TRY(2); __VG_LSB_IS(1);
+    }
+
+  if (__builtin_expect (data != 0, 1))
+    return __VG_lsb (data);
+  else
+    return 0;
+}
+
+static inline uintptr_t
+vg_lsb64 (uint64_t data)
+{
+#if __WORDSIZE == 64
+  return vg_lsb (data);
+#else
+  int d = vg_lsb (data);
+  if (d)
+    return d;
+  d = vg_lsb (data >> 32);
+  if (d)
+    return d + 32;
+  return 0;
+#endif
+}
+
+#endif