bzero & bcopy alignment

[Ivan Voras]

Following recent discussion on alignment of bzero() and bcopy(), I've
added some statistics collecting code to bzero() and bcopy() for
practice (on a RELENG_6 box), and here are the cumulative results for
argument alignment:

128: 117190
64: 46495
32: 745178
16: 35313
8: 64580
4: 131045
2: 17969
1: 25099

This is somewhat early after bootup. First number is the alignment,
second argument is the number of calls that passed a pointer having the
alignment (e.g. there were 131045 instances of arguments which had data
aligned to 4 bytes in either bcopy or bzero). After some compiling
(start of a buildkernel), the data is:

128: 341440
64: 66812
32: 1020807
16: 75574
8: 192189
4: 266904
2: 44975
1: 36411

If the data is correct, most data seem to be aligned fairly ok.

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