--- /dev/null
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+// See the LICENSE file in the project root for more information.
+
+#ifndef _BITPOSITION_H_
+#define _BITPOSITION_H_
+
+//------------------------------------------------------------------------
+// BitPosition: Return the position of the single bit that is set in 'value'.
+//
+// Return Value:
+// The position (0 is LSB) of bit that is set in 'value'
+//
+// Notes:
+// 'value' must have exactly one bit set.
+// The algorithm is as follows:
+// - PRIME is a prime bigger than sizeof(unsigned int), which is not of the
+// form 2^n-1.
+// - Taking the modulo of 'value' with this will produce a unique hash for all
+// powers of 2 (which is what "value" is).
+// - Entries in hashTable[] which are -1 should never be used. There
+// should be PRIME-8*sizeof(value) entries which are -1 .
+//
+inline
+unsigned BitPosition(unsigned value)
+{
+ _ASSERTE((value != 0) && ((value & (value-1)) == 0));
+#ifndef _TARGET_AMD64_
+ const unsigned PRIME = 37;
+
+ static const char hashTable[PRIME] =
+ {
+ -1, 0, 1, 26, 2, 23, 27, -1, 3, 16,
+ 24, 30, 28, 11, -1, 13, 4, 7, 17, -1,
+ 25, 22, 31, 15, 29, 10, 12, 6, -1, 21,
+ 14, 9, 5, 20, 8, 19, 18
+ };
+
+ _ASSERTE(PRIME >= 8*sizeof(value));
+ _ASSERTE(sizeof(hashTable) == PRIME);
+
+
+ unsigned hash = value % PRIME;
+ unsigned index = hashTable[hash];
+ _ASSERTE(index != (unsigned char)-1);
+#else
+ // not enabled for x86 because BSF is extremely slow on Atom
+ // (15 clock cycles vs 1-3 on any other Intel CPU post-P4)
+ DWORD index;
+ BitScanForward(&index, value);
+#endif
+ return index;
+}
+
+#endif
return (iBits);
}
-//------------------------------------------------------------------------
-// BitPosition: Return the position of the single bit that is set in 'value'.
-//
-// Return Value:
-// The position (0 is LSB) of bit that is set in 'value'
-//
-// Notes:
-// 'value' must have exactly one bit set.
-// The algorithm is as follows:
-// - PRIME is a prime bigger than sizeof(unsigned int), which is not of the
-// form 2^n-1.
-// - Taking the modulo of 'value' with this will produce a unique hash for all
-// powers of 2 (which is what "value" is).
-// - Entries in hashTable[] which are -1 should never be used. There
-// should be PRIME-8*sizeof(value) entries which are -1 .
-//
-inline
-unsigned BitPosition(unsigned value)
-{
- _ASSERTE((value != 0) && ((value & (value-1)) == 0));
-#ifndef _TARGET_AMD64_
- const unsigned PRIME = 37;
-
- static const char hashTable[PRIME] =
- {
- -1, 0, 1, 26, 2, 23, 27, -1, 3, 16,
- 24, 30, 28, 11, -1, 13, 4, 7, 17, -1,
- 25, 22, 31, 15, 29, 10, 12, 6, -1, 21,
- 14, 9, 5, 20, 8, 19, 18
- };
-
- _ASSERTE(PRIME >= 8*sizeof(value));
- _ASSERTE(sizeof(hashTable) == PRIME);
-
-
- unsigned hash = value % PRIME;
- unsigned index = hashTable[hash];
- _ASSERTE(index != (unsigned char)-1);
-#else
- // not enabled for x86 because BSF is extremely slow on Atom
- // (15 clock cycles vs 1-3 on any other Intel CPU post-P4)
- DWORD index;
- BitScanForward(&index, value);
-#endif
- return index;
-}
-
+#include "bitposition.h"
// Used to remove trailing zeros from Decimal types.
// NOTE: Assumes hi32 bits are empty (used for conversions from Cy->Dec)