Re: LibTomMath forked [SSE2 addons]

From: Arnold Stang (stang13_at_anonymous.to)
Date: 06/30/04 

Date: Wed, 30 Jun 2004 16:49:55 GMT

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Tom St Denis wrote:

| This is funny.... check this out
|
|
|>Now with SSE2 [and ICC -O3 -xN -ip]
|>
|>Timing Multiplying:
|> 4 digits: 400 cycles
|> 8 digits: 764 cycles
|> 12 digits: 1280 cycles
|> 16 digits: 1868 cycles
|> 20 digits: 3068 cycles
|> 24 digits: 4020 cycles
|> 28 digits: 5146 cycles
|> 32 digits: 6382 cycles
|> 36 digits: 7766 cycles
|>Timing Squaring:
|> 4 digits: 344 cycles
|> 8 digits: 644 cycles
|> 12 digits: 1056 cycles
|> 16 digits: 1550 cycles
|> 20 digits: 2202 cycles
|> 24 digits: 2866 cycles
|> 28 digits: 3566 cycles
|> 32 digits: 4310 cycles
|> 36 digits: 5122 cycles
|
|
| Now with GCC [v3.3.3, -march=pentium4 -mcpu=pentium4 -O3
| -fomit-frame-pointer -funroll-loops]
|
| Timing Multiplying:
| 4 digits: 464 cycles
| 8 digits: 740 cycles
| 12 digits: 1118 cycles
| 16 digits: 1616 cycles
| 20 digits: 2162 cycles
| 24 digits: 2858 cycles
| 28 digits: 3590 cycles
| 32 digits: 4400 cycles
| 36 digits: 5478 cycles
| Timing Squaring:
| 4 digits: 460 cycles
| 8 digits: 766 cycles
| 12 digits: 1076 cycles
| 16 digits: 1460 cycles
| 20 digits: 1848 cycles
| 24 digits: 2300 cycles
| 28 digits: 2824 cycles
| 32 digits: 3514 cycles
| 36 digits: 4196 cycles
|
| Seems GCC optimizes the code better than Intels own C compiler...
|
| Ok I'm done now ;-) Sorry about all the posts... but it's just fun
hacking
| and might benefit someone.
|
| Tom

Please, Tom --- take this to the sandbox.

Your friend, Arnold
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