Intel Assembler optimization

Posted by Søren Haagerup on Stack Overflow See other posts from Stack Overflow or by Søren Haagerup
Published on 2010-05-01T14:30:54Z Indexed on 2010/05/01 14:37 UTC
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Filed under:

vtune

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assembler

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intel

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optimization

I'm currently trying to optimize the code emitted from a home-made compiler, for a home-made language.

I've tried out Intel VTune to see where the bottlenecks are: http://www.imada.sdu.dk/~sorenh07/misc/vtune-assembly-optimization.png

I find it very impressive that a "subl"-instruction is responsible for over 38% of the clockticks in a program running for 30-90 seconds! Can anybody give an explanation why?

The "optimization report" feature in VTune apparently doesn't exist for programs not compiled with icc. Does there exist a program which suggests optimization for assembler code? (that is, not code coming from a high-level language).

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