On Mon, 11 Aug 2008, Wolfgang Denk wrote:
In message Pine.LNX.4.64.0808111238420.30591@axis700.grange you wrote:
Ok, would this be better
u32 reg; u32 pclk = get_PCLK(); u32 baudrate = gd->baudrate; int i;
reg = pclk / baudrate / 16 - 1; i = (pclk / baudrate) % 16;
Is "reg" still used anywhere else?
No, I'll remove it.
This way the compiler does optimize it to only one division, and the operations say what they do, and there doesn't seem to be any need for comment left. Still, the code produced by this is 1 asm instruction longer than my original code:-)
Is the generated code equivalent? This smells like a subtle bug...
Don't see a bug there, both look correct. The C-code is different too - one uses "%", another one multiplication and subtraction, don't think it should be alarming that the resulting asm-code is different too.
Thanks Guennadi --- Guennadi Liakhovetski, Ph.D.
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