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 for <linuxppc-dev@lists.ozlabs.org>; Thu, 13 Jul 2017 16:46:28 +1000 (AEST)
Date: Thu, 13 Jul 2017 01:46:13 -0500
From: Segher Boessenkool <segher@kernel.crashing.org>
To: Matt Brown <matthew.brown.dev@gmail.com>
Cc: linuxppc-dev@lists.ozlabs.org, anton@samba.org
Subject: Re: [PATCH 1/5] powerpc/lib/sstep: Add cmpb instruction emulation
Message-ID: <20170713064612.GZ13471@gate.crashing.org>
References: <20170713032548.451-1-matthew.brown.dev@gmail.com>
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On Thu, Jul 13, 2017 at 01:25:44PM +1000, Matt Brown wrote:
> +static nokprobe_inline void do_cmpb(struct pt_regs *regs, unsigned long v1,
> +				unsigned long v2, int rd)
> +{
> +	unsigned long out_val, mask;
> +	int i;
> +
> +	out_val = 0;
> +	for (i = 0; i < 8; i++) {
> +		mask = 0xff << (i * 8);

0xffUL ?

> +
> +		if ((v1 & mask) == (v2 & mask))
> +			out_val |= mask;
> +	}
> +
> +	regs->gpr[rd] = out_val;
> +}


Segher