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-rw-r--r--src/utils/bit_ops.h103
1 files changed, 0 insertions, 103 deletions
diff --git a/src/utils/bit_ops.h b/src/utils/bit_ops.h
deleted file mode 100644
index 0072fde71..000000000
--- a/src/utils/bit_ops.h
+++ /dev/null
@@ -1,103 +0,0 @@
-/*
-* Bit/Word Operations
-* (C) 1999-2008 Jack Lloyd
-*
-* Distributed under the terms of the Botan license
-*/
-
-#ifndef BOTAN_BIT_OPS_H__
-#define BOTAN_BIT_OPS_H__
-
-#include <botan/types.h>
-
-namespace Botan {
-
-/**
-* Power of 2 test. T should be an unsigned integer type
-* @param arg an integer value
-* @return true iff arg is 2^n for some n > 0
-*/
-template<typename T>
-inline bool is_power_of_2(T arg)
- {
- return ((arg != 0 && arg != 1) && ((arg & (arg-1)) == 0));
- }
-
-/**
-* Return the index of the highest set bit
-* T is an unsigned integer type
-* @param n an integer value
-* @return index of the highest set bit in n
-*/
-template<typename T>
-inline size_t high_bit(T n)
- {
- for(size_t i = 8*sizeof(T); i > 0; --i)
- if((n >> (i - 1)) & 0x01)
- return i;
- return 0;
- }
-
-/**
-* Return the index of the lowest set bit
-* T is an unsigned integer type
-* @param n an integer value
-* @return index of the lowest set bit in n
-*/
-template<typename T>
-inline size_t low_bit(T n)
- {
- for(size_t i = 0; i != 8*sizeof(T); ++i)
- if((n >> i) & 0x01)
- return (i + 1);
- return 0;
- }
-
-/**
-* Return the number of significant bytes in n
-* @param n an integer value
-* @return number of significant bytes in n
-*/
-template<typename T>
-inline size_t significant_bytes(T n)
- {
- for(size_t i = 0; i != sizeof(T); ++i)
- if(get_byte(i, n))
- return sizeof(T)-i;
- return 0;
- }
-
-/**
-* Compute Hamming weights
-* @param n an integer value
-* @return number of bits in n set to 1
-*/
-template<typename T>
-inline size_t hamming_weight(T n)
- {
- const byte NIBBLE_WEIGHTS[] = {
- 0, 1, 1, 2, 1, 2, 2, 3, 1, 2, 2, 3, 2, 3, 3, 4 };
-
- size_t weight = 0;
- for(size_t i = 0; i != 2*sizeof(T); ++i)
- weight += NIBBLE_WEIGHTS[(n >> (4*i)) & 0x0F];
- return weight;
- }
-
-/**
-* Count the trailing zero bits in n
-* @param n an integer value
-* @return maximum x st 2^x divides n
-*/
-template<typename T>
-inline size_t ctz(T n)
- {
- for(size_t i = 0; i != 8*sizeof(T); ++i)
- if((n >> i) & 0x01)
- return i;
- return 8*sizeof(T);
- }
-
-}
-
-#endif