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From: Kumar Gala <galak@kernel.crashing.org>
Subject: Re: [PATCH] powerpc: emulate power5 popcntb instruction
Date: Fri, 18 Aug 2006 14:42:16 -0500
To: will_schmidt@vnet.ibm.com
Cc: linuxppc-dev@ozlabs.org, Paul Mackerras <paulus@samba.org>
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>
> +static int emulate_popcntb_inst(struct pt_regs *regs, u32 instword)
> +{
> +	u32 ra,rs;
> +	unsigned long tmp;
> +
> +	ra = (instword >> 16) & 0x1f;
> +	rs = (instword >> 21) & 0x1f;
> +
> +	tmp = regs->gpr[rs];
> +	tmp = tmp - ((tmp >> 1) & 0x5555555555555555);
> +	tmp = (tmp & 0x3333333333333333) + ((tmp >> 2) &  
> 0x3333333333333333);
> +	tmp = (tmp + (tmp >> 4)) & 0x0f0f0f0f0f0f0f0f;
> +	regs->gpr[ra] = tmp;
> +
> +	return 0;
> +}

This is going to give warnings on ppc32 kernel compiles, maybe  
something like:

(unsigned long) 0x5555555555555555ull

- kumar