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NetBSD/sys/arch/arm/include/byte_swap.h

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* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
2002-08-14 19:08:57 +04:00
/* $NetBSD: byte_swap.h,v 1.2 2002/08/14 15:08:58 thorpej Exp $ */
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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/*-
* Copyright (c) 1997, 1999, 2002 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Charles M. Hannum, Neil A. Carson, and Jason R. Thorpe.
*
* 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. All advertising materials mentioning features or use of this software
* must display the following acknowledgement:
* This product includes software developed by the NetBSD
* Foundation, Inc. and its contributors.
* 4. Neither the name of The NetBSD Foundation 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#ifndef _ARM_BYTE_SWAP_H_
#define _ARM_BYTE_SWAP_H_
#include <sys/types.h>
static __inline u_int32_t
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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__byte_swap_32_variable(u_int32_t v)
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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{
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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u_int32_t t1;
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
2002-08-14 02:41:36 +04:00
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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t1 = v ^ ((v << 16) | (v >> 16));
t1 &= 0xff00ffff;
v = (v >> 8) | (v << 24);
v ^= (t1 >> 8);
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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return (v);
}
static __inline u_int16_t
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
2002-08-14 19:08:57 +04:00
__byte_swap_16_variable(u_int16_t v)
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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{
__asm __volatile(
"mov %0, %1, ror #8\n"
"orr %0, %0, %0, lsr #16\n"
"bic %0, %0, %0, lsl #16"
: "=r" (v)
: "0" (v));
return (v);
}
#ifdef __OPTIMIZE__
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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#define __byte_swap_32_constant(x) \
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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((((x) & 0xff000000) >> 24) | \
(((x) & 0x00ff0000) >> 8) | \
(((x) & 0x0000ff00) << 8) | \
(((x) & 0x000000ff) << 24))
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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#define __byte_swap_16_constant(x) \
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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((((x) & 0xff00) >> 8) | \
(((x) & 0x00ff) << 8))
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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#define __byte_swap_32(x) \
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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(__builtin_constant_p((x)) ? \
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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__byte_swap_32_constant(x) : __byte_swap_32_variable(x))
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
2002-08-14 02:41:36 +04:00
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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#define __byte_swap_16(x) \
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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(__builtin_constant_p((x)) ? \
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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__byte_swap_16_constant(x) : __byte_swap_16_variable(x))
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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#else
* Rename "word" -> 16, and "long" -> 32, as suggested by Ben Harris. * Replace __byte_swap_32_variable() with a C version from Richard Earnshaw that generates nearly identical assembly (and it would be exactly identical with the addition of another peephole to GCC ARM back-end).
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#define __byte_swap_32(x) __byte_swap_32_variable(x)
#define __byte_swap_16(x) __byte_swap_16_variable(x)
Byte-swapping optimizations, enabled if compiling with GCC: * Byte-swap 16-bit and 32-bit constants at compile-time. * Inline 16-bit and 32-bit variable byte-swaps. These take 3 and 4 insns, respectively, and inlining saves the minimum 6 cycle penalty to call/return from the byte swap function.
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#endif /* __OPTIMIZE__ */
#endif /* _ARM_BYTE_SWAP_H_ */