Add --disable-dtb option to suppress writing the DTB to memory

[riscv-isa-sim.git] / softfloat / s_countLeadingZeros64.c

diff --git a/softfloat/s_countLeadingZeros64.c b/softfloat/s_countLeadingZeros64.c
old mode 100755 (executable)
new mode 100644 (file)
index 79f4280..0045741
--- a/softfloat/s_countLeadingZeros64.c
+++ b/softfloat/s_countLeadingZeros64.c
@@ -1,18 +1,57 @@
 
+/*============================================================================
+
+This C source file is part of the SoftFloat IEEE Floating-Point Arithmetic
+Package, Release 3d, by John R. Hauser.
+
+Copyright 2011, 2012, 2013, 2014, 2015 The Regents of the University of
+California.  All rights reserved.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ 1. Redistributions of source code must retain the above copyright notice,
+    this list of conditions, and the following disclaimer.
+
+ 2. Redistributions in binary form must reproduce the above copyright notice,
+    this list of conditions, and the following disclaimer in the documentation
+    and/or other materials provided with the distribution.
+
+ 3. Neither the name of the University nor the names of its contributors may
+    be used to endorse or promote products derived from this software without
+    specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS "AS IS", AND ANY
+EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, ARE
+DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE FOR ANY
+DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
+LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
+ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+=============================================================================*/
+
 #include <stdint.h>
-#include "primitives.h"
 #include "platform.h"
 
-int softfloat_countLeadingZeros64( uint64_t a )
+#ifndef softfloat_countLeadingZeros64
+
+#define softfloat_countLeadingZeros64 softfloat_countLeadingZeros64
+#include "primitives.h"
+
+uint_fast8_t softfloat_countLeadingZeros64( uint64_t a )
 {
-    int count;
+    uint_fast8_t count;
     uint32_t a32;
 
-    count = 32;
-    a32 = a;
-    if ( UINT64_C( 0x100000000 ) <= a ) {
-        count = 0;
-        a32 = a>>32;
+    count = 0;
+    a32 = a>>32;
+    if ( ! a32 ) {
+        count = 32;
+        a32 = a;
     }
     /*------------------------------------------------------------------------
     | From here, result is current count + count leading zeros of `a32'.
@@ -25,8 +64,10 @@ int softfloat_countLeadingZeros64( uint64_t a )
         count += 8;
         a32 <<= 8;
     }
-    count += softfloat_countLeadingZeros8[ a32>>24 ];
+    count += softfloat_countLeadingZeros8[a32>>24];
     return count;
 
 }
 
+#endif
+