31409617a4
This is a slight improvement over the rep movsb loop Change-Id: Id71d9bfe5330b154a5c62fac85ce3955ae89b057 Signed-off-by: Stefan Reinauer <reinauer@google.com> Reviewed-on: http://review.coreboot.org/1742 Tested-by: build bot (Jenkins) Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
17 lines
306 B
C
17 lines
306 B
C
#include <string.h>
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void *memcpy(void *dest, const void *src, size_t n)
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{
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unsigned long d0, d1, d2;
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asm volatile(
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"rep ; movsl\n\t"
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"movl %4,%%ecx\n\t"
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"rep ; movsb\n\t"
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: "=&c" (d0), "=&D" (d1), "=&S" (d2)
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: "0" (n >> 2), "g" (n & 3), "1" (dest), "2" (src)
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: "memory"
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);
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return dest;
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}
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