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Date: Thu, 03 Aug 2006 12:10:55 -0700
From: Peter Grehan <grehan@freebsd.org>
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To: Maxim Sobolev <sobomax@FreeBSD.org>
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Cc: Peter Grehan <grehan@FreeBSD.org>, freebsd-ppc@FreeBSD.org
Subject: Re: Unaligned 64-bits access on FreeBSD/powerpc
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> According to the following link, unaligned floating-point 64-bits access 
> isn't supported in the PowerPC:
> 
> http://www-128.ibm.com/developerworks/library/pa-dalign/

  Yep, that's right: I should have mentioned that unaligned ints are OK. 
Which your program demonstrates :)

>         atype = "64";
>         for (i = 0; i < 256; i++) {
>             apoint = (uint8_t *)&(buf[i]);
>             v64 = *(uint64_t *)apoint;
>         }

  Would you be able to do a disassembly on this ? I suspect gcc is using 
floating-point regs to do the 64-bit loads.

later,

Peter.