Ejemplo n.º 1
0
static void
lower_load_store(nir_builder *b,
                 nir_intrinsic_instr *intrin,
                 glsl_type_size_align_func size_align)
{
   b->cursor = nir_before_instr(&intrin->instr);

   nir_deref_instr *deref = nir_src_as_deref(intrin->src[0]);
   nir_variable *var = nir_deref_instr_get_variable(deref);

   nir_ssa_def *offset =
      nir_iadd_imm(b, nir_build_deref_offset(b, deref, size_align),
                      var->data.location);

   unsigned align, UNUSED size;
   size_align(deref->type, &size, &align);

   if (intrin->intrinsic == nir_intrinsic_load_deref) {
      nir_intrinsic_instr *load =
         nir_intrinsic_instr_create(b->shader, nir_intrinsic_load_scratch);
      load->num_components = intrin->num_components;
      load->src[0] = nir_src_for_ssa(offset);
      nir_intrinsic_set_align(load, align, 0);
      nir_ssa_dest_init(&load->instr, &load->dest,
                        intrin->dest.ssa.num_components,
                        intrin->dest.ssa.bit_size, NULL);
      nir_builder_instr_insert(b, &load->instr);

      nir_ssa_def *value = &load->dest.ssa;
      if (glsl_type_is_boolean(deref->type))
         value = nir_b2i32(b, value);

      nir_ssa_def_rewrite_uses(&intrin->dest.ssa,
                               nir_src_for_ssa(&load->dest.ssa));
   } else {
      assert(intrin->intrinsic == nir_intrinsic_store_deref);

      assert(intrin->src[1].is_ssa);
      nir_ssa_def *value = intrin->src[1].ssa;
      if (glsl_type_is_boolean(deref->type))
         value = nir_i2b(b, value);

      nir_intrinsic_instr *store =
         nir_intrinsic_instr_create(b->shader, nir_intrinsic_store_scratch);
      store->num_components = intrin->num_components;
      store->src[0] = nir_src_for_ssa(value);
      store->src[1] = nir_src_for_ssa(offset);
      nir_intrinsic_set_write_mask(store, nir_intrinsic_write_mask(intrin));
      nir_intrinsic_set_align(store, align, 0);
      nir_builder_instr_insert(b, &store->instr);
   }

   nir_instr_remove(&intrin->instr);
   nir_deref_instr_remove_if_unused(deref);
}
Ejemplo n.º 2
0
static void
convert_instr(nir_builder *bld, nir_alu_instr *alu)
{
   nir_ssa_def *numer, *denom, *af, *bf, *a, *b, *q, *r;
   nir_op op = alu->op;
   bool is_signed;

   if ((op != nir_op_idiv) &&
       (op != nir_op_udiv) &&
       (op != nir_op_umod))
      return;

   is_signed = (op == nir_op_idiv);

   bld->cursor = nir_before_instr(&alu->instr);

   numer = nir_ssa_for_alu_src(bld, alu, 0);
   denom = nir_ssa_for_alu_src(bld, alu, 1);

   if (is_signed) {
      af = nir_i2f(bld, numer);
      bf = nir_i2f(bld, denom);
      af = nir_fabs(bld, af);
      bf = nir_fabs(bld, bf);
      a  = nir_iabs(bld, numer);
      b  = nir_iabs(bld, denom);
   } else {
      af = nir_u2f(bld, numer);
      bf = nir_u2f(bld, denom);
      a  = numer;
      b  = denom;
   }

   /* get first result: */
   bf = nir_frcp(bld, bf);
   bf = nir_isub(bld, bf, nir_imm_int(bld, 2));  /* yes, really */
   q  = nir_fmul(bld, af, bf);

   if (is_signed) {
      q = nir_f2i(bld, q);
   } else {
      q = nir_f2u(bld, q);
   }

   /* get error of first result: */
   r = nir_imul(bld, q, b);
   r = nir_isub(bld, a, r);
   r = nir_u2f(bld, r);
   r = nir_fmul(bld, r, bf);
   r = nir_f2u(bld, r);

   /* add quotients: */
   q = nir_iadd(bld, q, r);

   /* correction: if modulus >= divisor, add 1 */
   r = nir_imul(bld, q, b);
   r = nir_isub(bld, a, r);

   r = nir_uge(bld, r, b);
   r = nir_b2i(bld, r);

   q = nir_iadd(bld, q, r);
   if (is_signed)  {
      /* fix the sign: */
      r = nir_ixor(bld, numer, denom);
      r = nir_ushr(bld, r, nir_imm_int(bld, 31));
      r = nir_i2b(bld, r);
      b = nir_ineg(bld, q);
      q = nir_bcsel(bld, r, b, q);
   }

   if (op == nir_op_umod) {
      /* division result in q */
      r = nir_imul(bld, q, b);
      q = nir_isub(bld, a, r);
   }

   assert(alu->dest.dest.is_ssa);
   nir_ssa_def_rewrite_uses(&alu->dest.dest.ssa, nir_src_for_ssa(q));
}