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Date: Mon, 06 Jul 2015 23:15:41 -0400
From: Alain Espinosa <alainesp@...ta.cu>
To: john-dev@...ts.openwall.com
Subject: Re: extend SIMD intrinsics



-------- Original message --------
From: Solar Designer <solar@...nwall.com> 
Date:07/06/2015 9:49 PM (GMT-05:00) 
To: john-dev@...ts.openwall.com 
Cc: 
Subject: Re: [john-dev] extend SIMD intrinsics 

> And why not:
> 
> a[i] = reload_state[i*16+0];

...We could, but I suspect the compiler would be more likely to do
something like an inline memcpy() instead of a SIMD load then.

In Visual C the difference of a simple assignment and a vload is that for the assignment the compiler generate an unaligned SIMD load instruction, and for vload it generates an aligned SIMD load with the usual restriction: if this memory access isn't aligned the required byte amount an exception is raised. In general the performance difference is negligible,  if any.

Regards, 
Alain
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