Which opcodes are faster at the CPU level?

Posted by Geotarget on Game Development See other posts from Game Development or by Geotarget
Published on 2012-04-11T09:52:59Z Indexed on 2012/04/11 11:43 UTC
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c++

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Performance

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optimization

In every programming language there are sets of opcodes that are recommended over others. I've tried to list them here, in order of speed.

Bitwise
Integer Addition / Subtraction
Integer Multiplication / Division
Comparison
Control flow
Float Addition / Subtraction
Float Multiplication / Division

Where you need high-performance code, C++ can be hand optimized in assembly, to use SIMD instructions or more efficient control flow, data types, etc. So I'm trying to understand if the data type (int32 / float32 / float64) or the operation used (*, +, &) affects performance at the CPU level.

Is a single multiply slower on the CPU than an addition?
In MCU theory you learn that speed of opcodes is determined by the number of CPU cycles it takes to execute. So does it mean that multiply takes 4 cycles and add takes 2?
Exactly what are the speed characteristics of the basic math and control flow opcodes?
If two opcodes take the same number of cycles to execute, then both can be used interchangeably without any performance gain / loss?
Any other technical details you can share regarding x86 CPU performance is appreciated

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