target-arm: A64: Add 2-reg-misc REV* instructions

Add the byte-reverse operations REV64, REV32 and REV16 from the
two-reg-misc group.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Alex Bennée 2014-02-03 23:31:52 +00:00 committed by Peter Maydell
parent d980fd59a4
commit 39d8211893

View File

@ -7446,6 +7446,75 @@ static void handle_2misc_narrow(DisasContext *s, int opcode, bool u, bool is_q,
}
}
static void handle_rev(DisasContext *s, int opcode, bool u,
bool is_q, int size, int rn, int rd)
{
int op = (opcode << 1) | u;
int opsz = op + size;
int grp_size = 3 - opsz;
int dsize = is_q ? 128 : 64;
int i;
if (opsz >= 3) {
unallocated_encoding(s);
return;
}
if (size == 0) {
/* Special case bytes, use bswap op on each group of elements */
int groups = dsize / (8 << grp_size);
for (i = 0; i < groups; i++) {
TCGv_i64 tcg_tmp = tcg_temp_new_i64();
read_vec_element(s, tcg_tmp, rn, i, grp_size);
switch (grp_size) {
case MO_16:
tcg_gen_bswap16_i64(tcg_tmp, tcg_tmp);
break;
case MO_32:
tcg_gen_bswap32_i64(tcg_tmp, tcg_tmp);
break;
case MO_64:
tcg_gen_bswap64_i64(tcg_tmp, tcg_tmp);
break;
default:
g_assert_not_reached();
}
write_vec_element(s, tcg_tmp, rd, i, grp_size);
tcg_temp_free_i64(tcg_tmp);
}
if (!is_q) {
clear_vec_high(s, rd);
}
} else {
int revmask = (1 << grp_size) - 1;
int esize = 8 << size;
int elements = dsize / esize;
TCGv_i64 tcg_rn = tcg_temp_new_i64();
TCGv_i64 tcg_rd = tcg_const_i64(0);
TCGv_i64 tcg_rd_hi = tcg_const_i64(0);
for (i = 0; i < elements; i++) {
int e_rev = (i & 0xf) ^ revmask;
int off = e_rev * esize;
read_vec_element(s, tcg_rn, rn, i, size);
if (off >= 64) {
tcg_gen_deposit_i64(tcg_rd_hi, tcg_rd_hi,
tcg_rn, off - 64, esize);
} else {
tcg_gen_deposit_i64(tcg_rd, tcg_rd, tcg_rn, off, esize);
}
}
write_vec_element(s, tcg_rd, rd, 0, MO_64);
write_vec_element(s, tcg_rd_hi, rd, 1, MO_64);
tcg_temp_free_i64(tcg_rd_hi);
tcg_temp_free_i64(tcg_rd);
tcg_temp_free_i64(tcg_rn);
}
}
/* C3.6.17 AdvSIMD two reg misc
* 31 30 29 28 24 23 22 21 17 16 12 11 10 9 5 4 0
* +---+---+---+-----------+------+-----------+--------+-----+------+------+
@ -7464,7 +7533,7 @@ static void disas_simd_two_reg_misc(DisasContext *s, uint32_t insn)
switch (opcode) {
case 0x0: /* REV64, REV32 */
case 0x1: /* REV16 */
unsupported_encoding(s, insn);
handle_rev(s, opcode, u, is_q, size, rn, rd);
return;
case 0x5: /* CNT, NOT, RBIT */
if (u && size == 0) {