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Date: Thu, 19 Dec 2013 13:04:45 -0800
From: Richard Henderson <rth@twiddle.net>
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Subject: Re: [Qemu-devel] [PATCH 17/21] target-arm: A64: add support for
 conditional compare insns
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To: Peter Maydell <peter.maydell@linaro.org>, qemu-devel@nongnu.org
Cc: patches@linaro.org, Michael Matz <matz@suse.de>, Claudio Fontana <claudio.fontana@linaro.org>, Dirk Mueller <dmueller@suse.de>, Will Newton <will.newton@linaro.org>, Laurent Desnogues <laurent.desnogues@gmail.com>, =?ISO-8859-1?Q?Alex_Benn=E9e?= <alex.bennee@linaro.org>, kvmarm@lists.cs.columbia.edu, Christoffer Dall <christoffer.dall@linaro.org>

On 12/17/2013 07:12 AM, Peter Maydell wrote:
> +static void disas_cc(DisasContext *s, uint32_t insn)
>  {
> +    unsigned int sf, op, y, cond, rn, nzcv, is_imm;
> +    int label_continue;
> +    TCGv_i64 tcg_tmp, tcg_y, tcg_rn;

Don't you get a may be used uninitialized warning for label_continue?


> +    tcg_tmp = tcg_temp_new_i64();
> +
> +    if (cond < 0x0e) { /* not always */
> +        int label_match = gen_new_label();
> +        label_continue = gen_new_label();
> +        arm_gen_test_cc(cond, label_match);
> +        /* nomatch: */
> +        tcg_gen_movi_i64(tcg_tmp, nzcv << 28);
> +        gen_set_nzcv(tcg_tmp);
> +        tcg_gen_br(label_continue);
> +        gen_set_label(label_match);
> +    }

You can't re-use tcg_tmp across basic blocks like this.


r~