tlx
rol.hpp
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/*******************************************************************************
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* tlx/math/rol.hpp
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*
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* rol32() to rotate bits left - mainly for portability.
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*
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* Part of tlx - http://panthema.net/tlx
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*
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* Copyright (C) 2018 Timo Bingmann <tb@panthema.net>
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*
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* All rights reserved. Published under the Boost Software License, Version 1.0
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******************************************************************************/
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#ifndef TLX_MATH_ROL_HEADER
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#define TLX_MATH_ROL_HEADER
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#include <cstdint>
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#ifdef _MSC_VER
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#include <cstdlib>
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#endif
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namespace
tlx
{
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//! \addtogroup tlx_math
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//! \{
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/******************************************************************************/
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// rol32() - rotate bits left in 32-bit integers
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//! rol32 - generic implementation
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static
inline
uint32_t
rol32_generic
(
const
uint32_t& x,
int
i) {
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return
(x <<
static_cast<
uint32_t
>
(i & 31)) |
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(x >>
static_cast<
uint32_t
>
((32 - (i & 31)) & 31));
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}
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#if (defined(__GNUC__) || defined(__clang__)) && (defined(__i386__) || defined(__x86_64__))
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//! rol32 - gcc/clang assembler
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static
inline
uint32_t
rol32
(
const
uint32_t& x,
int
i) {
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uint32_t x1 = x;
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asm
(
"roll %%cl,%0"
:
"=r"
(x1) :
"0"
(x1),
"c"
(i));
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return
x1;
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}
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#elif defined(_MSC_VER)
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//! rol32 - MSVC intrinsic
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static
inline
uint32_t
rol32
(
const
uint32_t& x,
int
i) {
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return
_rotl(x, i);
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}
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#else
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//! rol32 - generic
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static
inline
uint32_t
rol32
(
const
uint32_t& x,
int
i) {
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return
rol32_generic
(x, i);
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}
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#endif
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/******************************************************************************/
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// rol64() - rotate bits left in 64-bit integers
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//! rol64 - generic implementation
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static
inline
uint64_t
rol64_generic
(
const
uint64_t& x,
int
i) {
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return
(x <<
static_cast<
uint64_t
>
(i & 63)) |
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(x >>
static_cast<
uint64_t
>
((64 - (i & 63)) & 63));
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}
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#if (defined(__GNUC__) || defined(__clang__)) && defined(__x86_64__)
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//! rol64 - gcc/clang assembler
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static
inline
uint64_t
rol64
(
const
uint64_t& x,
int
i) {
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uint64_t x1 = x;
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asm
(
"rolq %%cl,%0"
:
"=r"
(x1) :
"0"
(x1),
"c"
(i));
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return
x1;
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}
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#elif defined(_MSC_VER)
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//! rol64 - MSVC intrinsic
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static
inline
uint64_t
rol64
(
const
uint64_t& x,
int
i) {
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return
_rotl64(x, i);
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}
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#else
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//! rol64 - generic
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static
inline
uint64_t
rol64
(
const
uint64_t& x,
int
i) {
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return
rol64_generic
(x, i);
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}
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#endif
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/******************************************************************************/
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//! \}
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}
// namespace tlx
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#endif // !TLX_MATH_ROL_HEADER
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/******************************************************************************/
tlx::rol64_generic
static uint64_t rol64_generic(const uint64_t &x, int i)
rol64 - generic implementation
Definition:
rol.hpp:75
tlx::rol32_generic
static uint32_t rol32_generic(const uint32_t &x, int i)
rol32 - generic implementation
Definition:
rol.hpp:41
tlx::rol64
static uint64_t rol64(const uint64_t &x, int i)
rol64 - generic
Definition:
rol.hpp:99
tlx
Definition:
exclusive_scan.hpp:17
tlx::rol32
static uint32_t rol32(const uint32_t &x, int i)
rol32 - generic
Definition:
rol.hpp:65
tlx
math
rol.hpp
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