static nir_src
get_deref_reg_src(nir_deref_instr *deref, struct locals_to_regs_state *state)
{
nir_builder *b = &state->builder;
nir_src src;
src.is_ssa = false;
src.reg.reg = get_reg_for_deref(deref, state);
src.reg.base_offset = 0;
src.reg.indirect = NULL;
/* It is possible for a user to create a shader that has an array with a
* single element and then proceed to access it indirectly. Indirectly
* accessing a non-array register is not allowed in NIR. In order to
* handle this case we just convert it to a direct reference.
*/
if (src.reg.reg->num_array_elems == 0)
return src;
unsigned inner_array_size = 1;
for (const nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
if (d->deref_type != nir_deref_type_array)
continue;
if (nir_src_is_const(d->arr.index) && !src.reg.indirect) {
src.reg.base_offset += nir_src_as_uint(d->arr.index) *
inner_array_size;
} else {
if (src.reg.indirect) {
assert(src.reg.base_offset == 0);
} else {
src.reg.indirect = ralloc(b->shader, nir_src);
*src.reg.indirect =
nir_src_for_ssa(nir_imm_int(b, src.reg.base_offset));
src.reg.base_offset = 0;
}
assert(src.reg.indirect->is_ssa);
nir_ssa_def *index = nir_i2i(b, nir_ssa_for_src(b, d->arr.index, 1), 32);
src.reg.indirect->ssa =
nir_iadd(b, src.reg.indirect->ssa,
nir_imul(b, index, nir_imm_int(b, inner_array_size)));
}
inner_array_size *= glsl_get_length(nir_deref_instr_parent(d)->type);
}
return src;
}
/* src[] = { buffer_index, offset }. No const_index */
static void
emit_intrinsic_load_ssbo(struct ir3_context *ctx, nir_intrinsic_instr *intr,
struct ir3_instruction **dst)
{
struct ir3_block *b = ctx->block;
struct ir3_instruction *ldgb, *src0, *src1, *byte_offset, *offset;
/* can this be non-const buffer_index? how do we handle that? */
int ibo_idx = ir3_ssbo_to_ibo(&ctx->so->image_mapping, nir_src_as_uint(intr->src[0]));
byte_offset = ir3_get_src(ctx, &intr->src[1])[0];
offset = ir3_get_src(ctx, &intr->src[2])[0];
/* src0 is uvec2(offset*4, 0), src1 is offset.. nir already *= 4: */
src0 = ir3_create_collect(ctx, (struct ir3_instruction*[]){
byte_offset,
create_immed(b, 0),
}, 2);
static unsigned
get_io_offset(nir_deref_instr *deref, bool is_vertex_input)
{
unsigned offset = 0;
for (nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
if (d->deref_type == nir_deref_type_array) {
if (!nir_src_is_const(d->arr.index))
return -1;
offset += glsl_count_attribute_slots(d->type, is_vertex_input) *
nir_src_as_uint(d->arr.index);
}
/* TODO: we can get the offset for structs here see nir_lower_io() */
}
return offset;
}
