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Date: Tue, 10 Apr 2018 08:59:04 -0400
From: "Emilio G. Cota" <cota@braap.org>
Message-ID: <20180410125904.GA22304@flamenco>
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Subject: Re: [Qemu-devel] [PATCH v2 17/17] target/riscv: convert to
 TranslatorOps
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To: Richard Henderson <richard.henderson@linaro.org>
Cc: qemu-devel@nongnu.org, Michael Clark <mjc@sifive.com>, Palmer Dabbelt <palmer@sifive.com>, Sagar Karandikar <sagark@eecs.berkeley.edu>, Bastian Koppelmann <kbastian@mail.uni-paderborn.de>

On Tue, Apr 10, 2018 at 11:24:37 +1000, Richard Henderson wrote:
> On 04/07/2018 04:20 AM, Emilio G. Cota wrote:
> > +        next_page = (ctx->base.pc_first & TARGET_PAGE_MASK) + TARGET_PAGE_SIZE;
> > +        if (ctx->base.pc_next >= next_page) {
> 
> This fails for the last page of the address space.
> Better is
> 
>   page_start = ctx->base.pc_first & TARGET_PAGE_MASK;
>   if (ctx->base.pc_next - page_start >= TARGET_PAGE_SIZE) {

Apart from the variable name change, I fail to see how this (A - B >= C)
is not equivalent to the above (A => B + C). What am I missing?

Thanks,

		Emilio