On 17 January 2018 at 16:14, Richard Henderson
<[email protected]> wrote:
> Signed-off-by: Richard Henderson <[email protected]>
> ---
> target/arm/translate-a64.c | 386
> ++++++++++++++++++++++++++++++++++++++-------
> 1 file changed, 329 insertions(+), 57 deletions(-)
>
> diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
> index 2495414603..1b5005637d 100644
> --- a/target/arm/translate-a64.c
> +++ b/target/arm/translate-a64.c
> @@ -6489,17 +6489,6 @@ static void handle_shri_with_rndacc(TCGv_i64 tcg_res,
> TCGv_i64 tcg_src,
> }
> }
>
> -/* Common SHL/SLI - Shift left with an optional insert */
> -static void handle_shli_with_ins(TCGv_i64 tcg_res, TCGv_i64 tcg_src,
> - bool insert, int shift)
> -{
> - if (insert) { /* SLI */
> - tcg_gen_deposit_i64(tcg_res, tcg_res, tcg_src, shift, 64 - shift);
> - } else { /* SHL */
> - tcg_gen_shli_i64(tcg_res, tcg_src, shift);
> - }
> -}
> -
> /* SRI: shift right with insert */
> static void handle_shri_with_ins(TCGv_i64 tcg_res, TCGv_i64 tcg_src,
> int size, int shift)
> @@ -6603,7 +6592,11 @@ static void handle_scalar_simd_shli(DisasContext *s,
> bool insert,
> tcg_rn = read_fp_dreg(s, rn);
> tcg_rd = insert ? read_fp_dreg(s, rd) : tcg_temp_new_i64();
>
> - handle_shli_with_ins(tcg_rd, tcg_rn, insert, shift);
> + if (insert) {
> + tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_rn, shift, 64 - shift);
> + } else {
> + tcg_gen_shli_i64(tcg_rd, tcg_rn, shift);
> + }
It looks like you're folding handle_shli_with_ins() into its
now only callsite, but handle_shri_with_ins() has been left as
its own function?
> +static void gen_shr8_ins_i64(TCGv_i64 d, TCGv_i64 a, int64_t shift)
> +{
> + uint64_t mask = (0xff >> shift) * (-1ull / 0xff);
> + TCGv_i64 t = tcg_temp_new_i64();
> +
> + tcg_gen_shri_i64(t, a, shift);
> + tcg_gen_andi_i64(t, t, mask);
> + tcg_gen_andi_i64(d, d, ~mask);
> + tcg_gen_or_i64(d, d, t);
> + tcg_temp_free_i64(t);
The previous code was able to work with just shifts and deposits --
why do we need to open-code this kind of mask-and-or now? Is this
because we now operate an i64 at a time when we used to operate
on smaller quantities at once?
thanks
-- PMM
