[U-Boot] [PATCH 1/3] memcpy: use 32-bit copies if possible

[Wolfgang Denk]

Dear Alessandro Rubini,

In message <20091008074114.GA30203 at mail.gnudd.com> you wrote:
>
> Since int is 32 also on 64bit systems, I used unsigned long.

Note that this is not guaranteed, though. It could be 64 bit as well.


>     	/* do it one word at a time (32 bits or 64 bits) if possible */
>     	if ( ((count | (int)s) & (sizeof(long) - 1)) == 0) {
>     		count /= sizeof(long);
>     		cl = (c & 0xff) | ((c & 0xff) << 8);
>     		cl |= cl << 16;
>     		if (sizeof(long) > 4)
>     			cl |= cl << 32;

How about:

		cl = 0;
		for (i=0; i<sizeof(long); ++i) {
			cl <<= 8;
			cl |= c & 0xff;
		}

GCC optimization will do the rest...

Best regards,

Wolfgang Denk

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