vsll.vi
No synopsis available.
This instruction is defined by:
-
V, version >= 0
This instruction is included in the following profiles:
-
RVA22S64 (Optional)
-
RVA22U64 (Optional)
Decode Variables
Bits<1> vm = $encoding[25];
Bits<5> vs2 = $encoding[24:20];
Bits<5> simm5 = $encoding[19:15];
Bits<5> vd = $encoding[11:7];
Execution
-
IDL
-
Sail
{
let SEW = get_sew();
let LMUL_pow = get_lmul_pow();
let num_elem = get_num_elem(LMUL_pow, SEW);
if illegal_normal(vd, vm) then { handle_illegal(); return RETIRE_FAIL };
let 'n = num_elem;
let 'm = SEW;
let vm_val : vector('n, dec, bool) = read_vmask(num_elem, vm, 0b00000);
let imm_val : bits('m) = sign_extend(simm);
let vs2_val : vector('n, dec, bits('m)) = read_vreg(num_elem, SEW, LMUL_pow, vs2);
let vd_val : vector('n, dec, bits('m)) = read_vreg(num_elem, SEW, LMUL_pow, vd);
result : vector('n, dec, bits('m)) = undefined;
mask : vector('n, dec, bool) = undefined;
(result, mask) = init_masked_result(num_elem, SEW, LMUL_pow, vd_val, vm_val);
foreach (i from 0 to (num_elem - 1)) {
if mask[i] then {
result[i] = match funct6 {
VI_VADD => vs2_val[i] + imm_val,
VI_VRSUB => imm_val - vs2_val[i],
VI_VAND => vs2_val[i] & imm_val,
VI_VOR => vs2_val[i] | imm_val,
VI_VXOR => vs2_val[i] ^ imm_val,
VI_VSADDU => unsigned_saturation('m, zero_extend('m + 1, vs2_val[i]) + zero_extend('m + 1, imm_val) ),
VI_VSADD => signed_saturation('m, sign_extend('m + 1, vs2_val[i]) + sign_extend('m + 1, imm_val) ),
VI_VSLL => {
let shift_amount = get_shift_amount(zero_extend('m, simm), SEW);
vs2_val[i] << shift_amount
},
VI_VSRL => {
let shift_amount = get_shift_amount(zero_extend('m, simm), SEW);
vs2_val[i] >> shift_amount
},
VI_VSRA => {
let shift_amount = get_shift_amount(zero_extend('m, simm), SEW);
let v_double : bits('m * 2) = sign_extend(vs2_val[i]);
slice(v_double >> shift_amount, 0, SEW)
},
VI_VSSRL => {
let shift_amount = get_shift_amount(zero_extend('m, simm), SEW);
let rounding_incr = get_fixed_rounding_incr(vs2_val[i], shift_amount);
(vs2_val[i] >> shift_amount) + zero_extend('m, rounding_incr)
},
VI_VSSRA => {
let shift_amount = get_shift_amount(zero_extend('m, simm), SEW);
let rounding_incr = get_fixed_rounding_incr(vs2_val[i], shift_amount);
let v_double : bits('m * 2) = sign_extend(vs2_val[i]);
slice(v_double >> shift_amount, 0, SEW) + zero_extend('m, rounding_incr)
}
}
}
};
write_vreg(num_elem, SEW, LMUL_pow, vd, result);
vstart = zeros();
RETIRE_SUCCESS
}