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	 1366557094
			
		
	
	
		1366557094
		
	
	
	
	
		
			
			There's no great advantage to using MMX instructions here on modern processors, since REP MOVSB/STOSB are optimized in microcode anyway and tend to run much faster than MMX/SSE/AVX variants. This also makes it much easier to implement high-level emulation of memcpy/memset in UserspaceEmulator once we get there. :^)
		
			
				
	
	
		
			52 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
			
		
		
	
	
			52 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			C
		
	
	
	
	
	
| /*
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|  * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
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|  * All rights reserved.
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|  *
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|  * Redistribution and use in source and binary forms, with or without
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|  * modification, are permitted provided that the following conditions are met:
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|  *
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|  * 1. Redistributions of source code must retain the above copyright notice, this
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|  *    list of conditions and the following disclaimer.
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|  *
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|  * 2. Redistributions in binary form must reproduce the above copyright notice,
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|  *    this list of conditions and the following disclaimer in the documentation
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|  *    and/or other materials provided with the distribution.
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|  *
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|  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
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|  * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
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|  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
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|  * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE
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|  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
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|  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
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|  * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
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|  * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
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|  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
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|  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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|  */
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| 
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| #pragma once
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| 
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| #include <AK/Types.h>
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| 
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| #if defined(KERNEL)
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| #    include <Kernel/StdLib.h>
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| #else
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| #    include <stdlib.h>
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| #    include <string.h>
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| #endif
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| 
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| ALWAYS_INLINE void fast_u32_copy(u32* dest, const u32* src, size_t count)
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| {
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|     asm volatile(
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|         "rep movsl\n"
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|         : "+S"(src), "+D"(dest), "+c"(count)::"memory");
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| }
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| 
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| ALWAYS_INLINE void fast_u32_fill(u32* dest, u32 value, size_t count)
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| {
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|     asm volatile(
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|         "rep stosl\n"
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|         : "=D"(dest), "=c"(count)
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|         : "D"(dest), "c"(count), "a"(value)
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|         : "memory");
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| }
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