Thread: Extracting Individual bits in C
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Unread 08-01-2004, 13:12
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Efficiency of underlying asm code
Hey, can anyone give me an idea about the relatative effeciency of the underlying assembly language code for using the shifting macros vs. using the union/structures method?

I suppose that most times the code ends up more or less identical but I wonder on this particular CPU with this particular compiler, if there is a major advantage one way or the other.

My main reason for asking is that I am dreaming about 100 million things I want to do in the interrupt service routine (ISR), 88 million of them involve such bit piddling, not being one who likes to stack up ISR upon ISR upon ISR, I am concerned about effeciency of the code that does these things.

Your comments welcome...

Joe J.
Last edited by Joe Johnson : 08-01-2004 at 13:13. Reason: typos, typos, everywhere...