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);
}
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));
}
