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Subject: Re: [Qemu-devel] [PATCH 10/60] AArch64: Add handling for br
	instructions
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To: Alexander Graf <agraf@suse.de>
Cc: Peter Maydell <peter.maydell@linaro.org>, Michael Matz <matz@suse.de>, qemu-devel@nongnu.org, C Fontana <claudio.fontana@linaro.org>, Dirk Mueller <dmueller@suse.de>, Laurent Desnogues <laurent.desnogues@gmail.com>, Christoffer Dall <christoffer.dall@linaro.org>

On 09/26/2013 05:48 PM, Alexander Graf wrote:
> +static void handle_br(DisasContext *s, uint32_t insn)
> +{
> +    int branch_type = get_bits(insn, 21, 2);
> +    int source = get_bits(insn, 5, 5);
> +
> +    switch (branch_type) {
> +    case 0: /* JMP */
> +        break;
> +    case 1: /* CALL */
> +        tcg_gen_movi_i64(cpu_reg(30), s->pc);
> +        break;
> +    case 2: /* RET */
> +        source = 30;
> +        break;

This is incorrect.  One can RET from any register; the only difference between
JMP and RET is a branch prediction hint irrelevant to QEMU.


r~