On Wed, Jul 19, 2017 at 13:34:47 -1000, Richard Henderson wrote:
> It is much shorter to reverse all 4 half-words in parallel
> than extract, reverse, and deposit each in turn.
>
> Suggested-by: Aurelien Jarno <aurel...@aurel32.net>
> Signed-off-by: Richard Henderson <r...@twiddle.net>
> ---
> target/arm/translate-a64.c | 24 ++++++------------------
> 1 file changed, 6 insertions(+), 18 deletions(-)
>
> diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
> index 3fa39023ca..5bb0f8ef22 100644
> --- a/target/arm/translate-a64.c
> +++ b/target/arm/translate-a64.c
> @@ -4043,25 +4043,13 @@ static void handle_rev16(DisasContext *s, unsigned
> int sf,
> TCGv_i64 tcg_rd = cpu_reg(s, rd);
> TCGv_i64 tcg_tmp = tcg_temp_new_i64();
> TCGv_i64 tcg_rn = read_cpu_reg(s, rn, sf);
> + TCGv_i64 mask = tcg_const_i64(sf ? 0x00ff00ff00ff00ffull : 0x00ff00ff);
>
> - tcg_gen_andi_i64(tcg_tmp, tcg_rn, 0xffff);
> - tcg_gen_bswap16_i64(tcg_rd, tcg_tmp);
> -
> - tcg_gen_shri_i64(tcg_tmp, tcg_rn, 16);
> - tcg_gen_andi_i64(tcg_tmp, tcg_tmp, 0xffff);
> - tcg_gen_bswap16_i64(tcg_tmp, tcg_tmp);
> - tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_tmp, 16, 16);
> -
> - if (sf) {
> - tcg_gen_shri_i64(tcg_tmp, tcg_rn, 32);
> - tcg_gen_andi_i64(tcg_tmp, tcg_tmp, 0xffff);
> - tcg_gen_bswap16_i64(tcg_tmp, tcg_tmp);
> - tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_tmp, 32, 16);
> -
> - tcg_gen_shri_i64(tcg_tmp, tcg_rn, 48);
> - tcg_gen_bswap16_i64(tcg_tmp, tcg_tmp);
> - tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_tmp, 48, 16);
> - }
> + tcg_gen_shri_i64(tcg_tmp, tcg_rn, 8);
> + tcg_gen_and_i64(tcg_rd, tcg_rn, mask);
> + tcg_gen_and_i64(tcg_tmp, tcg_tmp, mask);
> + tcg_gen_shli_i64(tcg_rd, tcg_rd, 8);
> + tcg_gen_or_i64(tcg_rd, tcg_rd, tcg_tmp);
>
> tcg_temp_free_i64(tcg_tmp);
const leak! patch below -- cut with `git am --scissors'.
Emilio
---8<---
Signed-off-by: Emilio G. Cota <c...@braap.org>
---
target/arm/translate-a64.c | 1 +
1 file changed, 1 insertion(+)
diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index 883e9df..58ed4c6 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -4044,20 +4044,21 @@ static void handle_rev16(DisasContext *s, unsigned int
sf,
TCGv_i64 tcg_tmp = tcg_temp_new_i64();
TCGv_i64 tcg_rn = read_cpu_reg(s, rn, sf);
TCGv_i64 mask = tcg_const_i64(sf ? 0x00ff00ff00ff00ffull : 0x00ff00ff);
tcg_gen_shri_i64(tcg_tmp, tcg_rn, 8);
tcg_gen_and_i64(tcg_rd, tcg_rn, mask);
tcg_gen_and_i64(tcg_tmp, tcg_tmp, mask);
tcg_gen_shli_i64(tcg_rd, tcg_rd, 8);
tcg_gen_or_i64(tcg_rd, tcg_rd, tcg_tmp);
+ tcg_temp_free_i64(mask);
tcg_temp_free_i64(tcg_tmp);
}
/* C3.5.7 Data-processing (1 source)
* 31 30 29 28 21 20 16 15 10 9 5 4 0
* +----+---+---+-----------------+---------+--------+------+------+
* | sf | 1 | S | 1 1 0 1 0 1 1 0 | opcode2 | opcode | Rn | Rd |
* +----+---+---+-----------------+---------+--------+------+------+
*/
static void disas_data_proc_1src(DisasContext *s, uint32_t insn)
--
2.7.4
