target-arm: A64: Add "Floating-point data-processing (3 source)" insns

This patch adds emulation for the "Floating-point data-processing (3 source)"
group of instructions.

Signed-off-by: Alexander Graf <agraf@suse.de>
[WN: Commit message tweak, merged single and double precision patches.
 Implement using muladd as suggested by Richard Henderson.]
Signed-off-by: Will Newton <will.newton@linaro.org>
[PMM: pull field decode up a level, use register accessors]
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <rth@twiddle.net>
This commit is contained in:
Alexander Graf 2014-01-04 22:15:50 +00:00 committed by Peter Maydell
parent 459cc34290
commit cd54be5fdb

View File

@ -3367,6 +3367,82 @@ static void disas_fp_2src(DisasContext *s, uint32_t insn)
}
}
/* C3.6.27 Floating-point data-processing (3 source) - single precision */
static void handle_fp_3src_single(DisasContext *s, bool o0, bool o1,
int rd, int rn, int rm, int ra)
{
TCGv_i32 tcg_op1, tcg_op2, tcg_op3;
TCGv_i32 tcg_res = tcg_temp_new_i32();
TCGv_ptr fpst = get_fpstatus_ptr();
tcg_op1 = read_fp_sreg(s, rn);
tcg_op2 = read_fp_sreg(s, rm);
tcg_op3 = read_fp_sreg(s, ra);
/* These are fused multiply-add, and must be done as one
* floating point operation with no rounding between the
* multiplication and addition steps.
* NB that doing the negations here as separate steps is
* correct : an input NaN should come out with its sign bit
* flipped if it is a negated-input.
*/
if (o1 == true) {
gen_helper_vfp_negs(tcg_op3, tcg_op3);
}
if (o0 != o1) {
gen_helper_vfp_negs(tcg_op1, tcg_op1);
}
gen_helper_vfp_muladds(tcg_res, tcg_op1, tcg_op2, tcg_op3, fpst);
write_fp_sreg(s, rd, tcg_res);
tcg_temp_free_ptr(fpst);
tcg_temp_free_i32(tcg_op1);
tcg_temp_free_i32(tcg_op2);
tcg_temp_free_i32(tcg_op3);
tcg_temp_free_i32(tcg_res);
}
/* C3.6.27 Floating-point data-processing (3 source) - double precision */
static void handle_fp_3src_double(DisasContext *s, bool o0, bool o1,
int rd, int rn, int rm, int ra)
{
TCGv_i64 tcg_op1, tcg_op2, tcg_op3;
TCGv_i64 tcg_res = tcg_temp_new_i64();
TCGv_ptr fpst = get_fpstatus_ptr();
tcg_op1 = read_fp_dreg(s, rn);
tcg_op2 = read_fp_dreg(s, rm);
tcg_op3 = read_fp_dreg(s, ra);
/* These are fused multiply-add, and must be done as one
* floating point operation with no rounding between the
* multiplication and addition steps.
* NB that doing the negations here as separate steps is
* correct : an input NaN should come out with its sign bit
* flipped if it is a negated-input.
*/
if (o1 == true) {
gen_helper_vfp_negd(tcg_op3, tcg_op3);
}
if (o0 != o1) {
gen_helper_vfp_negd(tcg_op1, tcg_op1);
}
gen_helper_vfp_muladdd(tcg_res, tcg_op1, tcg_op2, tcg_op3, fpst);
write_fp_dreg(s, rd, tcg_res);
tcg_temp_free_ptr(fpst);
tcg_temp_free_i64(tcg_op1);
tcg_temp_free_i64(tcg_op2);
tcg_temp_free_i64(tcg_op3);
tcg_temp_free_i64(tcg_res);
}
/* C3.6.27 Floating point data-processing (3 source)
* 31 30 29 28 24 23 22 21 20 16 15 14 10 9 5 4 0
* +---+---+---+-----------+------+----+------+----+------+------+------+
@ -3375,7 +3451,24 @@ static void disas_fp_2src(DisasContext *s, uint32_t insn)
*/
static void disas_fp_3src(DisasContext *s, uint32_t insn)
{
unsupported_encoding(s, insn);
int type = extract32(insn, 22, 2);
int rd = extract32(insn, 0, 5);
int rn = extract32(insn, 5, 5);
int ra = extract32(insn, 10, 5);
int rm = extract32(insn, 16, 5);
bool o0 = extract32(insn, 15, 1);
bool o1 = extract32(insn, 21, 1);
switch (type) {
case 0:
handle_fp_3src_single(s, o0, o1, rd, rn, rm, ra);
break;
case 1:
handle_fp_3src_double(s, o0, o1, rd, rn, rm, ra);
break;
default:
unallocated_encoding(s);
}
}
/* C3.6.28 Floating point immediate