target-arm: A64: Add SIMD EXT

Add support for the SIMD EXT instruction (the only one in its
group, C3.6.1).

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Peter Maydell 2014-01-31 14:47:30 +00:00
parent 384b26fb06
commit 5c73747f3c

View file

@ -4646,6 +4646,25 @@ static void disas_data_proc_fp(DisasContext *s, uint32_t insn)
}
}
static void do_ext64(DisasContext *s, TCGv_i64 tcg_left, TCGv_i64 tcg_right,
int pos)
{
/* Extract 64 bits from the middle of two concatenated 64 bit
* vector register slices left:right. The extracted bits start
* at 'pos' bits into the right (least significant) side.
* We return the result in tcg_right, and guarantee not to
* trash tcg_left.
*/
TCGv_i64 tcg_tmp = tcg_temp_new_i64();
assert(pos > 0 && pos < 64);
tcg_gen_shri_i64(tcg_right, tcg_right, pos);
tcg_gen_shli_i64(tcg_tmp, tcg_left, 64 - pos);
tcg_gen_or_i64(tcg_right, tcg_right, tcg_tmp);
tcg_temp_free_i64(tcg_tmp);
}
/* C3.6.1 EXT
* 31 30 29 24 23 22 21 20 16 15 14 11 10 9 5 4 0
* +---+---+-------------+-----+---+------+---+------+---+------+------+
@ -4654,7 +4673,65 @@ static void disas_data_proc_fp(DisasContext *s, uint32_t insn)
*/
static void disas_simd_ext(DisasContext *s, uint32_t insn)
{
unsupported_encoding(s, insn);
int is_q = extract32(insn, 30, 1);
int op2 = extract32(insn, 22, 2);
int imm4 = extract32(insn, 11, 4);
int rm = extract32(insn, 16, 5);
int rn = extract32(insn, 5, 5);
int rd = extract32(insn, 0, 5);
int pos = imm4 << 3;
TCGv_i64 tcg_resl, tcg_resh;
if (op2 != 0 || (!is_q && extract32(imm4, 3, 1))) {
unallocated_encoding(s);
return;
}
tcg_resh = tcg_temp_new_i64();
tcg_resl = tcg_temp_new_i64();
/* Vd gets bits starting at pos bits into Vm:Vn. This is
* either extracting 128 bits from a 128:128 concatenation, or
* extracting 64 bits from a 64:64 concatenation.
*/
if (!is_q) {
read_vec_element(s, tcg_resl, rn, 0, MO_64);
if (pos != 0) {
read_vec_element(s, tcg_resh, rm, 0, MO_64);
do_ext64(s, tcg_resh, tcg_resl, pos);
}
tcg_gen_movi_i64(tcg_resh, 0);
} else {
TCGv_i64 tcg_hh;
typedef struct {
int reg;
int elt;
} EltPosns;
EltPosns eltposns[] = { {rn, 0}, {rn, 1}, {rm, 0}, {rm, 1} };
EltPosns *elt = eltposns;
if (pos >= 64) {
elt++;
pos -= 64;
}
read_vec_element(s, tcg_resl, elt->reg, elt->elt, MO_64);
elt++;
read_vec_element(s, tcg_resh, elt->reg, elt->elt, MO_64);
elt++;
if (pos != 0) {
do_ext64(s, tcg_resh, tcg_resl, pos);
tcg_hh = tcg_temp_new_i64();
read_vec_element(s, tcg_hh, elt->reg, elt->elt, MO_64);
do_ext64(s, tcg_hh, tcg_resh, pos);
tcg_temp_free_i64(tcg_hh);
}
}
write_vec_element(s, tcg_resl, rd, 0, MO_64);
tcg_temp_free_i64(tcg_resl);
write_vec_element(s, tcg_resh, rd, 1, MO_64);
tcg_temp_free_i64(tcg_resh);
}
/* C3.6.2 TBL/TBX