Re: How can I link the kernel with libgcc ?

From: Carlos Munoz
Date: Fri Mar 10 2006 - 14:59:57 EST


Al Viro wrote:

On Fri, Mar 10, 2006 at 10:03:58AM -0800, Carlos Munoz wrote:


ydef[22] = (u_int32_t)(log10((double)(over & 0x0000003f)) /
log10(2));



You've got to be kidding. Let's take a good look at that expression:
log10(x)/log10(2) is what? Right, base-2 logarithm of x. Then you cast
it to unsigned, i.e. round it down. In other words, you want to know the
highest bit in (over & 0x3f). Which is to say, (fls(over & 0x3f) - 1).
Sigh...


Hi Al,

You are right, so easy. I will look at the data sheet and make sure the same approach can be applied to all places calling for log10 calculations. I wonder why the data sheet calls for log10 calculations. It threw me off... should have know better though.

Thanks,


Carlos Munoz
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