nir/lcssa: handle deref instructions properly

Reviewed-by: Jason Ekstrand <jason@jlekstrand.net>
Fixes: 414148cdc1 "nir: Support deref instructions in loop_analyze"
This commit is contained in:
Daniel Schürmann
2019-08-14 18:52:50 +02:00
parent 7c56a68c8b
commit 204846ad06
2 changed files with 26 additions and 14 deletions

View File

@@ -111,9 +111,6 @@ convert_loop_exit_for_ssa(nir_ssa_def *def, void *void_state)
if (all_uses_inside_loop)
return true;
/* We don't want derefs ending up in phi sources */
assert(def->parent_instr->type != nir_instr_type_deref);
/* Initialize a phi-instruction */
nir_phi_instr *phi = nir_phi_instr_create(state->shader);
nir_ssa_dest_init(&phi->instr, &phi->dest,
@@ -131,6 +128,25 @@ convert_loop_exit_for_ssa(nir_ssa_def *def, void *void_state)
}
nir_instr_insert_before_block(block_after_loop, &phi->instr);
nir_ssa_def *dest = &phi->dest.ssa;
/* deref instructions need a cast after the phi */
if (def->parent_instr->type == nir_instr_type_deref) {
nir_deref_instr *cast =
nir_deref_instr_create(state->shader, nir_deref_type_cast);
nir_deref_instr *instr = nir_instr_as_deref(def->parent_instr);
cast->mode = instr->mode;
cast->type = instr->type;
cast->parent = nir_src_for_ssa(&phi->dest.ssa);
cast->cast.ptr_stride = nir_deref_instr_ptr_as_array_stride(instr);
nir_ssa_dest_init(&cast->instr, &cast->dest,
phi->dest.ssa.num_components,
phi->dest.ssa.bit_size, NULL);
nir_instr_insert(nir_after_phis(block_after_loop), &cast->instr);
dest = &cast->dest.ssa;
}
/* Run through all uses and rewrite those outside the loop to point to
* the phi instead of pointing to the ssa-def.
@@ -142,15 +158,13 @@ convert_loop_exit_for_ssa(nir_ssa_def *def, void *void_state)
}
if (!is_use_inside_loop(use, state->loop)) {
nir_instr_rewrite_src(use->parent_instr, use,
nir_src_for_ssa(&phi->dest.ssa));
nir_instr_rewrite_src(use->parent_instr, use, nir_src_for_ssa(dest));
}
}
nir_foreach_if_use_safe(use, def) {
if (!is_if_use_inside_loop(use, state->loop)) {
nir_if_rewrite_condition(use->parent_if,
nir_src_for_ssa(&phi->dest.ssa));
nir_if_rewrite_condition(use->parent_if, nir_src_for_ssa(dest));
}
}