vmsbc.vvm

No synopsis available.

This instruction is defined by:

V, version >= 0

This instruction is included in the following profiles:

RVA22S64 (Optional)
RVA22U64 (Optional)

Encoding

Assembly format

vmsbc.vvm vs2, vs1, vd

Synopsis

No description available.

Access

M	HS	U	VS	VU
Always	Always	Always	Always	Always

Always

Decode Variables

Bits<5> vs2 = $encoding[24:20];
Bits<5> vs1 = $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_vd_unmasked() then { handle_illegal(); return RETIRE_FAIL };

  let 'n = num_elem;
  let 'm = SEW;

  let vm_val  : vector('n, dec, bool)     = read_vmask_carry(num_elem, 0b0, 0b00000);
  let vs1_val : vector('n, dec, bits('m)) = read_vreg(num_elem, SEW, LMUL_pow, vs1);
  let vs2_val : vector('n, dec, bits('m)) = read_vreg(num_elem, SEW, LMUL_pow, vs2);
  let vd_val  : vector('n, dec, bool)     = read_vmask(num_elem, 0b0, vd);
  result      : vector('n, dec, bool)     = undefined;
  mask        : vector('n, dec, bool)     = undefined;

  (result, mask) = init_masked_result_carry(num_elem, SEW, LMUL_pow, vd_val);

  foreach (i from 0 to (num_elem - 1)) {
    if mask[i] then {
      let res : bool = match funct6 {
        VVM_VMADC    => unsigned(vs2_val[i]) + unsigned(vs1_val[i]) + unsigned(bool_to_bits(vm_val[i])) > 2 ^ SEW - 1,
        VVM_VMSBC    => unsigned(vs2_val[i]) - unsigned(vs1_val[i]) - unsigned(bool_to_bits(vm_val[i])) < 0
      };
      result[i] = res
    }
  };

  write_vmask(num_elem, vd, result);
  vstart = zeros();
  RETIRE_SUCCESS
}