Re: [Qemu-devel] [V3 PATCH 11/14] target-ppc: Add ISA 2.06 ftdiv Instruction

[Richard Henderson]

On 12/18/2013 12:49 PM, Tom Musta wrote:
> +    env->crf[bf] = 0x8 | (fg_flag ? 4 : 0) | (fe_flag ? 2 : 0);
> +}

You should return that value instead of assigning it.  Then you need neither
the env nor bf arguments, and the whole function can be TCG_CALL_NO_RWG_SE.

> +static void gen_ftdiv(DisasContext *ctx)
> +{
> +    TCGv_i32 bf;
> +    if (unlikely(!ctx->fpu_enabled)) {
> +        gen_exception(ctx, POWERPC_EXCP_FPU);
> +        return;
> +    }
> +    /* NIP cannot be restored if the memory exception comes from an helper */
> +    gen_update_nip(ctx, ctx->nip - 4);
> +    bf = tcg_const_i32(crfD(ctx->opcode));
> +    gen_helper_ftdiv(cpu_env, bf, cpu_fpr[rA(ctx->opcode)],
> +                     cpu_fpr[rB(ctx->opcode)]);
> +}

What memory exception?

Assign the result to cpu_crf[bf] here.



r~