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authorYang Zhang <yang.z.zhang@intel.com>2015-08-28 09:58:54 +0800
committerYang Zhang <yang.z.zhang@intel.com>2015-09-01 12:44:00 +0800
commite44e3482bdb4d0ebde2d8b41830ac2cdb07948fb (patch)
tree66b09f592c55df2878107a468a91d21506104d3f /qemu/roms/ipxe/src/core/isqrt.c
parent9ca8dbcc65cfc63d6f5ef3312a33184e1d726e00 (diff)
Add qemu 2.4.0
Change-Id: Ic99cbad4b61f8b127b7dc74d04576c0bcbaaf4f5 Signed-off-by: Yang Zhang <yang.z.zhang@intel.com>
Diffstat (limited to 'qemu/roms/ipxe/src/core/isqrt.c')
-rw-r--r--qemu/roms/ipxe/src/core/isqrt.c52
1 files changed, 52 insertions, 0 deletions
diff --git a/qemu/roms/ipxe/src/core/isqrt.c b/qemu/roms/ipxe/src/core/isqrt.c
new file mode 100644
index 000000000..35c918d19
--- /dev/null
+++ b/qemu/roms/ipxe/src/core/isqrt.c
@@ -0,0 +1,52 @@
+/*
+ * Copyright (C) 2014 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or any later version.
+ *
+ * This program 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
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER );
+
+/** @file
+ *
+ * Integer square root
+ *
+ */
+
+#include <ipxe/isqrt.h>
+
+/**
+ * Find integer square root
+ *
+ * @v value Value
+ * @v isqrt Integer square root of value
+ */
+unsigned long isqrt ( unsigned long value ) {
+ unsigned long result = 0;
+ unsigned long bit = ( 1UL << ( ( 8 * sizeof ( bit ) ) - 2 ) );
+
+ while ( bit > value )
+ bit >>= 2;
+ while ( bit ) {
+ if ( value >= ( result + bit ) ) {
+ value -= ( result + bit );
+ result = ( ( result >> 1 ) + bit );
+ } else {
+ result >>= 1;
+ }
+ bit >>= 2;
+ }
+ return result;
+}