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Re: Altivec: Extracting Floats From Vector Float

On Apr 2, 2004, at 12:50 PM, Roger Kylin wrote:
I have not done a lot of profiling (just using -gp and gprof), but the
GetFourFloats function that does the extraction is not listed
anywhere... Perhaps because I have it in-lined. As I said before,
though, the vector version is 2 times faster than the scalar version....

You need to run Shark on this and double click your function. Scroll down the code until you reach the GetFourFloats segment. Double click that line. It should either direct you to a pile of inline asm in your larger function (lots of lines highlighted) or to a small set of instructions containing a branch instruction that branches off to GetFourFloats that might look like this:

	b 	$+1024  <GetFourFloats>

Either way, Shark will tell you how much time you are spending doing this. If it isn't much time, don't worry about it. Go to where the hotspot is and fix that.

Ian
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References: 
 >RE: Altivec: Extracting Floats From Vector Float (From: "Roger Kylin" <email@hidden>)



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