#include "nir.h"
#include "nir_builder.h"
#include "nir_deref.h"
+#include "util/hash_table.h"
+
+static bool
+is_trivial_deref_cast(nir_deref_instr *cast)
+{
+ nir_deref_instr *parent = nir_src_as_deref(cast->parent);
+ if (!parent)
+ return false;
+
+ return cast->mode == parent->mode &&
+ cast->type == parent->type &&
+ cast->dest.ssa.num_components == parent->dest.ssa.num_components &&
+ cast->dest.ssa.bit_size == parent->dest.ssa.bit_size;
+}
void
nir_deref_path_init(nir_deref_path *path,
*tail = NULL;
for (nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
+ if (d->deref_type == nir_deref_type_cast && is_trivial_deref_cast(d))
+ continue;
count++;
if (count <= max_short_path_len)
*(--head) = d;
#ifndef NDEBUG
/* Just in case someone uses short_path by accident */
for (unsigned i = 0; i < ARRAY_SIZE(path->_short_path); i++)
- path->_short_path[i] = (void *)0xdeadbeef;
+ path->_short_path[i] = (void *)(uintptr_t)0xdeadbeef;
#endif
path->path = ralloc_array(mem_ctx, nir_deref_instr *, count + 1);
head = tail = path->path + count;
*tail = NULL;
- for (nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d))
+ for (nir_deref_instr *d = deref; d; d = nir_deref_instr_parent(d)) {
+ if (d->deref_type == nir_deref_type_cast && is_trivial_deref_cast(d))
+ continue;
*(--head) = d;
+ }
done:
assert(head == path->path);
assert(tail == head + count);
- assert((*head)->deref_type == nir_deref_type_var);
assert(*tail == NULL);
}
for (nir_deref_instr *d = instr; d; d = nir_deref_instr_parent(d)) {
/* If anyone is using this deref, leave it alone */
assert(d->dest.is_ssa);
- if (!list_empty(&d->dest.ssa.uses))
+ if (!list_is_empty(&d->dest.ssa.uses))
break;
nir_instr_remove(&d->instr);
if (instr->deref_type == nir_deref_type_cast)
return true;
- if (instr->deref_type == nir_deref_type_array &&
- !nir_src_as_const_value(instr->arr.index))
+ if ((instr->deref_type == nir_deref_type_array ||
+ instr->deref_type == nir_deref_type_ptr_as_array) &&
+ !nir_src_is_const(instr->arr.index))
return true;
instr = nir_deref_instr_parent(instr);
return false;
}
+bool
+nir_deref_instr_is_known_out_of_bounds(nir_deref_instr *instr)
+{
+ for (; instr; instr = nir_deref_instr_parent(instr)) {
+ if (instr->deref_type == nir_deref_type_array &&
+ nir_src_is_const(instr->arr.index) &&
+ nir_src_as_uint(instr->arr.index) >=
+ glsl_get_length(nir_deref_instr_parent(instr)->type))
+ return true;
+ }
+
+ return false;
+}
+
+bool
+nir_deref_instr_has_complex_use(nir_deref_instr *deref)
+{
+ nir_foreach_use(use_src, &deref->dest.ssa) {
+ nir_instr *use_instr = use_src->parent_instr;
+
+ switch (use_instr->type) {
+ case nir_instr_type_deref: {
+ nir_deref_instr *use_deref = nir_instr_as_deref(use_instr);
+
+ /* A var deref has no sources */
+ assert(use_deref->deref_type != nir_deref_type_var);
+
+ /* If a deref shows up in an array index or something like that, it's
+ * a complex use.
+ */
+ if (use_src != &use_deref->parent)
+ return true;
+
+ /* Anything that isn't a basic struct or array deref is considered to
+ * be a "complex" use. In particular, we don't allow ptr_as_array
+ * because we assume that opt_deref will turn any non-complex
+ * ptr_as_array derefs into regular array derefs eventually so passes
+ * which only want to handle simple derefs will pick them up in a
+ * later pass.
+ */
+ if (use_deref->deref_type != nir_deref_type_struct &&
+ use_deref->deref_type != nir_deref_type_array_wildcard &&
+ use_deref->deref_type != nir_deref_type_array)
+ return true;
+
+ if (nir_deref_instr_has_complex_use(use_deref))
+ return true;
+
+ continue;
+ }
+
+ case nir_instr_type_intrinsic: {
+ nir_intrinsic_instr *use_intrin = nir_instr_as_intrinsic(use_instr);
+ switch (use_intrin->intrinsic) {
+ case nir_intrinsic_load_deref:
+ assert(use_src == &use_intrin->src[0]);
+ continue;
+
+ case nir_intrinsic_copy_deref:
+ assert(use_src == &use_intrin->src[0] ||
+ use_src == &use_intrin->src[1]);
+ continue;
+
+ case nir_intrinsic_store_deref:
+ /* A use in src[1] of a store means we're taking that pointer and
+ * writing it to a variable. Because we have no idea who will
+ * read that variable and what they will do with the pointer, it's
+ * considered a "complex" use. A use in src[0], on the other
+ * hand, is a simple use because we're just going to dereference
+ * it and write a value there.
+ */
+ if (use_src == &use_intrin->src[0])
+ continue;
+ return true;
+
+ default:
+ return true;
+ }
+ unreachable("Switch default failed");
+ }
+
+ default:
+ return true;
+ }
+ }
+
+ nir_foreach_if_use(use, &deref->dest.ssa)
+ return true;
+
+ return false;
+}
+
+unsigned
+nir_deref_instr_ptr_as_array_stride(nir_deref_instr *deref)
+{
+ switch (deref->deref_type) {
+ case nir_deref_type_array:
+ return glsl_get_explicit_stride(nir_deref_instr_parent(deref)->type);
+ case nir_deref_type_ptr_as_array:
+ return nir_deref_instr_ptr_as_array_stride(nir_deref_instr_parent(deref));
+ case nir_deref_type_cast:
+ return deref->cast.ptr_stride;
+ default:
+ return 0;
+ }
+}
+
static unsigned
type_get_array_stride(const struct glsl_type *elem_type,
glsl_type_size_align_func size_align)
{
unsigned elem_size, elem_align;
- glsl_get_natural_size_align_bytes(elem_type, &elem_size, &elem_align);
+ size_align(elem_type, &elem_size, &elem_align);
return ALIGN_POT(elem_size, elem_align);
}
glsl_type_size_align_func size_align,
unsigned field_idx)
{
- assert(glsl_type_is_struct(struct_type));
+ assert(glsl_type_is_struct_or_ifc(struct_type));
unsigned offset = 0;
for (unsigned i = 0; i <= field_idx; i++) {
unsigned elem_size, elem_align;
- glsl_get_natural_size_align_bytes(glsl_get_struct_field(struct_type, i),
- &elem_size, &elem_align);
+ size_align(glsl_get_struct_field(struct_type, i), &elem_size, &elem_align);
offset = ALIGN_POT(offset, elem_align);
if (i < field_idx)
offset += elem_size;
nir_deref_path path;
nir_deref_path_init(&path, deref, NULL);
- assert(path.path[0]->deref_type == nir_deref_type_var);
-
unsigned offset = 0;
for (nir_deref_instr **p = &path.path[1]; *p; p++) {
- if ((*p)->deref_type == nir_deref_type_array) {
- offset += nir_src_as_const_value((*p)->arr.index)->u32[0] *
+ switch ((*p)->deref_type) {
+ case nir_deref_type_array:
+ offset += nir_src_as_uint((*p)->arr.index) *
type_get_array_stride((*p)->type, size_align);
- } else if ((*p)->deref_type == nir_deref_type_struct) {
+ break;
+ case nir_deref_type_struct: {
/* p starts at path[1], so this is safe */
nir_deref_instr *parent = *(p - 1);
offset += struct_type_get_field_offset(parent->type, size_align,
(*p)->strct.index);
- } else {
+ break;
+ }
+ case nir_deref_type_cast:
+ /* A cast doesn't contribute to the offset */
+ break;
+ default:
unreachable("Unsupported deref type");
}
}
nir_deref_path path;
nir_deref_path_init(&path, deref, NULL);
- assert(path.path[0]->deref_type == nir_deref_type_var);
-
- nir_ssa_def *offset = nir_imm_int(b, 0);
+ nir_ssa_def *offset = nir_imm_intN_t(b, 0, deref->dest.ssa.bit_size);
for (nir_deref_instr **p = &path.path[1]; *p; p++) {
- if ((*p)->deref_type == nir_deref_type_array) {
+ switch ((*p)->deref_type) {
+ case nir_deref_type_array: {
nir_ssa_def *index = nir_ssa_for_src(b, (*p)->arr.index, 1);
- nir_ssa_def *stride =
- nir_imm_int(b, type_get_array_stride((*p)->type, size_align));
- offset = nir_iadd(b, offset, nir_imul(b, index, stride));
- } else if ((*p)->deref_type == nir_deref_type_struct) {
+ int stride = type_get_array_stride((*p)->type, size_align);
+ offset = nir_iadd(b, offset, nir_amul_imm(b, index, stride));
+ break;
+ }
+ case nir_deref_type_struct: {
/* p starts at path[1], so this is safe */
nir_deref_instr *parent = *(p - 1);
unsigned field_offset =
struct_type_get_field_offset(parent->type, size_align,
(*p)->strct.index);
- nir_iadd(b, offset, nir_imm_int(b, field_offset));
- } else {
+ offset = nir_iadd_imm(b, offset, field_offset);
+ break;
+ }
+ case nir_deref_type_cast:
+ /* A cast doesn't contribute to the offset */
+ break;
+ default:
unreachable("Unsupported deref type");
}
}
continue;
nir_deref_instr *deref = nir_instr_as_deref(instr);
+ if (deref->deref_type == nir_deref_type_cast)
+ continue;
nir_variable_mode parent_mode;
if (deref->deref_type == nir_deref_type_var) {
}
}
-/** Returns true if the storage referrenced to by deref completely contains
- * the storage referenced by sub.
- */
+static bool
+modes_may_alias(nir_variable_mode a, nir_variable_mode b)
+{
+ /* Generic pointers can alias with SSBOs */
+ if ((a == nir_var_mem_ssbo || a == nir_var_mem_global) &&
+ (b == nir_var_mem_ssbo || b == nir_var_mem_global))
+ return true;
+
+ /* In the general case, pointers can only alias if they have the same mode.
+ *
+ * NOTE: In future, with things like OpenCL generic pointers, this may not
+ * be true and will have to be re-evaluated. However, with graphics only,
+ * it should be safe.
+ */
+ return a == b;
+}
+
+static bool
+deref_path_contains_coherent_decoration(nir_deref_path *path)
+{
+ assert(path->path[0]->deref_type == nir_deref_type_var);
+
+ if (path->path[0]->var->data.access & ACCESS_COHERENT)
+ return true;
+
+ for (nir_deref_instr **p = &path->path[1]; *p; p++) {
+ if ((*p)->deref_type != nir_deref_type_struct)
+ continue;
+
+ const struct glsl_type *struct_type = (*(p - 1))->type;
+ const struct glsl_struct_field *field =
+ glsl_get_struct_field_data(struct_type, (*p)->strct.index);
+ if (field->memory_coherent)
+ return true;
+ }
+
+ return false;
+}
+
nir_deref_compare_result
nir_compare_deref_paths(nir_deref_path *a_path,
nir_deref_path *b_path)
{
- if (a_path->path[0]->var != b_path->path[0]->var)
- return 0;
+ if (!modes_may_alias(b_path->path[0]->mode, a_path->path[0]->mode))
+ return nir_derefs_do_not_alias;
+
+ if (a_path->path[0]->deref_type != b_path->path[0]->deref_type)
+ return nir_derefs_may_alias_bit;
+
+ if (a_path->path[0]->deref_type == nir_deref_type_var) {
+ if (a_path->path[0]->var != b_path->path[0]->var) {
+ /* Shader and function temporaries aren't backed by memory so two
+ * distinct variables never alias.
+ */
+ static const nir_variable_mode temp_var_modes =
+ nir_var_shader_temp | nir_var_function_temp;
+ if ((a_path->path[0]->mode & temp_var_modes) ||
+ (b_path->path[0]->mode & temp_var_modes))
+ return nir_derefs_do_not_alias;
+
+ /* If they are both declared coherent or have coherent somewhere in
+ * their path (due to a member of an interface being declared
+ * coherent), we have to assume we that we could have any kind of
+ * aliasing. Otherwise, they could still alias but the client didn't
+ * tell us and that's their fault.
+ */
+ if (deref_path_contains_coherent_decoration(a_path) &&
+ deref_path_contains_coherent_decoration(b_path))
+ return nir_derefs_may_alias_bit;
+
+ /* If we can chase the deref all the way back to the variable and
+ * they're not the same variable and at least one is not declared
+ * coherent, we know they can't possibly alias.
+ */
+ return nir_derefs_do_not_alias;
+ }
+ } else {
+ assert(a_path->path[0]->deref_type == nir_deref_type_cast);
+ /* If they're not exactly the same cast, it's hard to compare them so we
+ * just assume they alias. Comparing casts is tricky as there are lots
+ * of things such as mode, type, etc. to make sure work out; for now, we
+ * just assume nit_opt_deref will combine them and compare the deref
+ * instructions.
+ *
+ * TODO: At some point in the future, we could be clever and understand
+ * that a float[] and int[] have the same layout and aliasing structure
+ * but double[] and vec3[] do not and we could potentially be a bit
+ * smarter here.
+ */
+ if (a_path->path[0] != b_path->path[0])
+ return nir_derefs_may_alias_bit;
+ }
/* Start off assuming they fully compare. We ignore equality for now. In
* the end, we'll determine that by containment.
nir_deref_instr **a_p = &a_path->path[1];
nir_deref_instr **b_p = &b_path->path[1];
+ while (*a_p != NULL && *a_p == *b_p) {
+ a_p++;
+ b_p++;
+ }
+
+ /* We're at either the tail or the divergence point between the two deref
+ * paths. Look to see if either contains cast or a ptr_as_array deref. If
+ * it does we don't know how to safely make any inferences. Hopefully,
+ * nir_opt_deref will clean most of these up and we can start inferring
+ * things again.
+ *
+ * In theory, we could do a bit better. For instance, we could detect the
+ * case where we have exactly one ptr_as_array deref in the chain after the
+ * divergence point and it's matched in both chains and the two chains have
+ * different constant indices.
+ */
+ for (nir_deref_instr **t_p = a_p; *t_p; t_p++) {
+ if ((*t_p)->deref_type == nir_deref_type_cast ||
+ (*t_p)->deref_type == nir_deref_type_ptr_as_array)
+ return nir_derefs_may_alias_bit;
+ }
+ for (nir_deref_instr **t_p = b_p; *t_p; t_p++) {
+ if ((*t_p)->deref_type == nir_deref_type_cast ||
+ (*t_p)->deref_type == nir_deref_type_ptr_as_array)
+ return nir_derefs_may_alias_bit;
+ }
+
while (*a_p != NULL && *b_p != NULL) {
nir_deref_instr *a_tail = *(a_p++);
nir_deref_instr *b_tail = *(b_p++);
b_tail->deref_type == nir_deref_type_array);
assert(a_tail->arr.index.is_ssa && b_tail->arr.index.is_ssa);
- nir_const_value *a_index_const =
- nir_src_as_const_value(a_tail->arr.index);
- nir_const_value *b_index_const =
- nir_src_as_const_value(b_tail->arr.index);
- if (a_index_const && b_index_const) {
+ if (nir_src_is_const(a_tail->arr.index) &&
+ nir_src_is_const(b_tail->arr.index)) {
/* If they're both direct and have different offsets, they
* don't even alias much less anything else.
*/
- if (a_index_const->u32[0] != b_index_const->u32[0])
- return 0;
+ if (nir_src_as_uint(a_tail->arr.index) !=
+ nir_src_as_uint(b_tail->arr.index))
+ return nir_derefs_do_not_alias;
} else if (a_tail->arr.index.ssa == b_tail->arr.index.ssa) {
/* They're the same indirect, continue on */
} else {
case nir_deref_type_struct: {
/* If they're different struct members, they don't even alias */
if (a_tail->strct.index != b_tail->strct.index)
- return 0;
+ return nir_derefs_do_not_alias;
break;
}
nir_deref_path a_path, b_path;
nir_deref_path_init(&a_path, a, NULL);
nir_deref_path_init(&b_path, b, NULL);
- assert(a_path.path[0]->deref_type == nir_deref_type_var);
- assert(b_path.path[0]->deref_type == nir_deref_type_var);
+ assert(a_path.path[0]->deref_type == nir_deref_type_var ||
+ a_path.path[0]->deref_type == nir_deref_type_cast);
+ assert(b_path.path[0]->deref_type == nir_deref_type_var ||
+ b_path.path[0]->deref_type == nir_deref_type_cast);
nir_deref_compare_result result = nir_compare_deref_paths(&a_path, &b_path);
return result;
}
+
+struct rematerialize_deref_state {
+ bool progress;
+ nir_builder builder;
+ nir_block *block;
+ struct hash_table *cache;
+};
+
+static nir_deref_instr *
+rematerialize_deref_in_block(nir_deref_instr *deref,
+ struct rematerialize_deref_state *state)
+{
+ if (deref->instr.block == state->block)
+ return deref;
+
+ if (!state->cache) {
+ state->cache = _mesa_pointer_hash_table_create(NULL);
+ }
+
+ struct hash_entry *cached = _mesa_hash_table_search(state->cache, deref);
+ if (cached)
+ return cached->data;
+
+ nir_builder *b = &state->builder;
+ nir_deref_instr *new_deref =
+ nir_deref_instr_create(b->shader, deref->deref_type);
+ new_deref->mode = deref->mode;
+ new_deref->type = deref->type;
+
+ if (deref->deref_type == nir_deref_type_var) {
+ new_deref->var = deref->var;
+ } else {
+ nir_deref_instr *parent = nir_src_as_deref(deref->parent);
+ if (parent) {
+ parent = rematerialize_deref_in_block(parent, state);
+ new_deref->parent = nir_src_for_ssa(&parent->dest.ssa);
+ } else {
+ nir_src_copy(&new_deref->parent, &deref->parent, new_deref);
+ }
+ }
+
+ switch (deref->deref_type) {
+ case nir_deref_type_var:
+ case nir_deref_type_array_wildcard:
+ /* Nothing more to do */
+ break;
+
+ case nir_deref_type_cast:
+ new_deref->cast.ptr_stride = deref->cast.ptr_stride;
+ break;
+
+ case nir_deref_type_array:
+ case nir_deref_type_ptr_as_array:
+ assert(!nir_src_as_deref(deref->arr.index));
+ nir_src_copy(&new_deref->arr.index, &deref->arr.index, new_deref);
+ break;
+
+ case nir_deref_type_struct:
+ new_deref->strct.index = deref->strct.index;
+ break;
+
+ default:
+ unreachable("Invalid deref instruction type");
+ }
+
+ nir_ssa_dest_init(&new_deref->instr, &new_deref->dest,
+ deref->dest.ssa.num_components,
+ deref->dest.ssa.bit_size,
+ deref->dest.ssa.name);
+ nir_builder_instr_insert(b, &new_deref->instr);
+
+ return new_deref;
+}
+
+static bool
+rematerialize_deref_src(nir_src *src, void *_state)
+{
+ struct rematerialize_deref_state *state = _state;
+
+ nir_deref_instr *deref = nir_src_as_deref(*src);
+ if (!deref)
+ return true;
+
+ nir_deref_instr *block_deref = rematerialize_deref_in_block(deref, state);
+ if (block_deref != deref) {
+ nir_instr_rewrite_src(src->parent_instr, src,
+ nir_src_for_ssa(&block_deref->dest.ssa));
+ nir_deref_instr_remove_if_unused(deref);
+ state->progress = true;
+ }
+
+ return true;
+}
+
+/** Re-materialize derefs in every block
+ *
+ * This pass re-materializes deref instructions in every block in which it is
+ * used. After this pass has been run, every use of a deref will be of a
+ * deref in the same block as the use. Also, all unused derefs will be
+ * deleted as a side-effect.
+ *
+ * Derefs used as sources of phi instructions are not rematerialized.
+ */
+bool
+nir_rematerialize_derefs_in_use_blocks_impl(nir_function_impl *impl)
+{
+ struct rematerialize_deref_state state = { 0 };
+ nir_builder_init(&state.builder, impl);
+
+ nir_foreach_block_unstructured(block, impl) {
+ state.block = block;
+
+ /* Start each block with a fresh cache */
+ if (state.cache)
+ _mesa_hash_table_clear(state.cache, NULL);
+
+ nir_foreach_instr_safe(instr, block) {
+ if (instr->type == nir_instr_type_deref &&
+ nir_deref_instr_remove_if_unused(nir_instr_as_deref(instr)))
+ continue;
+
+ /* If a deref is used in a phi, we can't rematerialize it, as the new
+ * derefs would appear before the phi, which is not valid.
+ */
+ if (instr->type == nir_instr_type_phi)
+ continue;
+
+ state.builder.cursor = nir_before_instr(instr);
+ nir_foreach_src(instr, rematerialize_deref_src, &state);
+ }
+
+#ifndef NDEBUG
+ nir_if *following_if = nir_block_get_following_if(block);
+ if (following_if)
+ assert(!nir_src_as_deref(following_if->condition));
+#endif
+ }
+
+ _mesa_hash_table_destroy(state.cache, NULL);
+
+ return state.progress;
+}
+
+static void
+nir_deref_instr_fixup_child_types(nir_deref_instr *parent)
+{
+ nir_foreach_use(use, &parent->dest.ssa) {
+ if (use->parent_instr->type != nir_instr_type_deref)
+ continue;
+
+ nir_deref_instr *child = nir_instr_as_deref(use->parent_instr);
+ switch (child->deref_type) {
+ case nir_deref_type_var:
+ unreachable("nir_deref_type_var cannot be a child");
+
+ case nir_deref_type_array:
+ case nir_deref_type_array_wildcard:
+ child->type = glsl_get_array_element(parent->type);
+ break;
+
+ case nir_deref_type_ptr_as_array:
+ child->type = parent->type;
+ break;
+
+ case nir_deref_type_struct:
+ child->type = glsl_get_struct_field(parent->type,
+ child->strct.index);
+ break;
+
+ case nir_deref_type_cast:
+ /* We stop the recursion here */
+ continue;
+ }
+
+ /* Recurse into children */
+ nir_deref_instr_fixup_child_types(child);
+ }
+}
+
+static bool
+is_trivial_array_deref_cast(nir_deref_instr *cast)
+{
+ assert(is_trivial_deref_cast(cast));
+
+ nir_deref_instr *parent = nir_src_as_deref(cast->parent);
+
+ if (parent->deref_type == nir_deref_type_array) {
+ return cast->cast.ptr_stride ==
+ glsl_get_explicit_stride(nir_deref_instr_parent(parent)->type);
+ } else if (parent->deref_type == nir_deref_type_ptr_as_array) {
+ return cast->cast.ptr_stride ==
+ nir_deref_instr_ptr_as_array_stride(parent);
+ } else {
+ return false;
+ }
+}
+
+static bool
+is_deref_ptr_as_array(nir_instr *instr)
+{
+ return instr->type == nir_instr_type_deref &&
+ nir_instr_as_deref(instr)->deref_type == nir_deref_type_ptr_as_array;
+}
+
+/**
+ * Remove casts that just wrap other casts.
+ */
+static bool
+opt_remove_cast_cast(nir_deref_instr *cast)
+{
+ nir_deref_instr *first_cast = cast;
+
+ while (true) {
+ nir_deref_instr *parent = nir_deref_instr_parent(first_cast);
+ if (parent == NULL || parent->deref_type != nir_deref_type_cast)
+ break;
+ first_cast = parent;
+ }
+ if (cast == first_cast)
+ return false;
+
+ nir_instr_rewrite_src(&cast->instr, &cast->parent,
+ nir_src_for_ssa(first_cast->parent.ssa));
+ return true;
+}
+
+static bool
+opt_remove_sampler_cast(nir_deref_instr *cast)
+{
+ assert(cast->deref_type == nir_deref_type_cast);
+ nir_deref_instr *parent = nir_src_as_deref(cast->parent);
+ if (parent == NULL)
+ return false;
+
+ /* Strip both types down to their non-array type and bail if there are any
+ * discrepancies in array lengths.
+ */
+ const struct glsl_type *parent_type = parent->type;
+ const struct glsl_type *cast_type = cast->type;
+ while (glsl_type_is_array(parent_type) && glsl_type_is_array(cast_type)) {
+ if (glsl_get_length(parent_type) != glsl_get_length(cast_type))
+ return false;
+ parent_type = glsl_get_array_element(parent_type);
+ cast_type = glsl_get_array_element(cast_type);
+ }
+
+ if (glsl_type_is_array(parent_type) || glsl_type_is_array(cast_type))
+ return false;
+
+ if (!glsl_type_is_sampler(parent_type) ||
+ cast_type != glsl_bare_sampler_type())
+ return false;
+
+ /* We're a cast from a more detailed sampler type to a bare sampler */
+ nir_ssa_def_rewrite_uses(&cast->dest.ssa,
+ nir_src_for_ssa(&parent->dest.ssa));
+ nir_instr_remove(&cast->instr);
+
+ /* Recursively crawl the deref tree and clean up types */
+ nir_deref_instr_fixup_child_types(parent);
+
+ return true;
+}
+
+/**
+ * Is this casting a struct to a contained struct.
+ * struct a { struct b field0 };
+ * ssa_5 is structa;
+ * deref_cast (structb *)ssa_5 (function_temp structb);
+ * converts to
+ * deref_struct &ssa_5->field0 (function_temp structb);
+ * This allows subsequent copy propagation to work.
+ */
+static bool
+opt_replace_struct_wrapper_cast(nir_builder *b, nir_deref_instr *cast)
+{
+ nir_deref_instr *parent = nir_src_as_deref(cast->parent);
+ if (!parent)
+ return false;
+
+ if (!glsl_type_is_struct(parent->type))
+ return false;
+
+ if (glsl_get_struct_field_offset(parent->type, 0) != 0)
+ return false;
+
+ if (cast->type != glsl_get_struct_field(parent->type, 0))
+ return false;
+
+ nir_deref_instr *replace = nir_build_deref_struct(b, parent, 0);
+ nir_ssa_def_rewrite_uses(&cast->dest.ssa, nir_src_for_ssa(&replace->dest.ssa));
+ nir_deref_instr_remove_if_unused(cast);
+ return true;
+}
+
+static bool
+opt_deref_cast(nir_builder *b, nir_deref_instr *cast)
+{
+ bool progress;
+
+ if (opt_replace_struct_wrapper_cast(b, cast))
+ return true;
+
+ if (opt_remove_sampler_cast(cast))
+ return true;
+
+ progress = opt_remove_cast_cast(cast);
+ if (!is_trivial_deref_cast(cast))
+ return progress;
+
+ bool trivial_array_cast = is_trivial_array_deref_cast(cast);
+
+ assert(cast->dest.is_ssa);
+ assert(cast->parent.is_ssa);
+
+ nir_foreach_use_safe(use_src, &cast->dest.ssa) {
+ /* If this isn't a trivial array cast, we can't propagate into
+ * ptr_as_array derefs.
+ */
+ if (is_deref_ptr_as_array(use_src->parent_instr) &&
+ !trivial_array_cast)
+ continue;
+
+ nir_instr_rewrite_src(use_src->parent_instr, use_src, cast->parent);
+ progress = true;
+ }
+
+ /* If uses would be a bit crazy */
+ assert(list_is_empty(&cast->dest.ssa.if_uses));
+
+ if (nir_deref_instr_remove_if_unused(cast))
+ progress = true;
+
+ return progress;
+}
+
+static bool
+opt_deref_ptr_as_array(nir_builder *b, nir_deref_instr *deref)
+{
+ assert(deref->deref_type == nir_deref_type_ptr_as_array);
+
+ nir_deref_instr *parent = nir_deref_instr_parent(deref);
+
+ if (nir_src_is_const(deref->arr.index) &&
+ nir_src_as_int(deref->arr.index) == 0) {
+ /* If it's a ptr_as_array deref with an index of 0, it does nothing
+ * and we can just replace its uses with its parent.
+ *
+ * The source of a ptr_as_array deref always has a deref_type of
+ * nir_deref_type_array or nir_deref_type_cast. If it's a cast, it
+ * may be trivial and we may be able to get rid of that too. Any
+ * trivial cast of trivial cast cases should be handled already by
+ * opt_deref_cast() above.
+ */
+ if (parent->deref_type == nir_deref_type_cast &&
+ is_trivial_deref_cast(parent))
+ parent = nir_deref_instr_parent(parent);
+ nir_ssa_def_rewrite_uses(&deref->dest.ssa,
+ nir_src_for_ssa(&parent->dest.ssa));
+ nir_instr_remove(&deref->instr);
+ return true;
+ }
+
+ if (parent->deref_type != nir_deref_type_array &&
+ parent->deref_type != nir_deref_type_ptr_as_array)
+ return false;
+
+ assert(parent->parent.is_ssa);
+ assert(parent->arr.index.is_ssa);
+ assert(deref->arr.index.is_ssa);
+
+ nir_ssa_def *new_idx = nir_iadd(b, parent->arr.index.ssa,
+ deref->arr.index.ssa);
+
+ deref->deref_type = parent->deref_type;
+ nir_instr_rewrite_src(&deref->instr, &deref->parent, parent->parent);
+ nir_instr_rewrite_src(&deref->instr, &deref->arr.index,
+ nir_src_for_ssa(new_idx));
+ return true;
+}
+
+bool
+nir_opt_deref_impl(nir_function_impl *impl)
+{
+ bool progress = false;
+
+ nir_builder b;
+ nir_builder_init(&b, impl);
+
+ nir_foreach_block(block, impl) {
+ nir_foreach_instr_safe(instr, block) {
+ if (instr->type != nir_instr_type_deref)
+ continue;
+
+ b.cursor = nir_before_instr(instr);
+
+ nir_deref_instr *deref = nir_instr_as_deref(instr);
+ switch (deref->deref_type) {
+ case nir_deref_type_ptr_as_array:
+ if (opt_deref_ptr_as_array(&b, deref))
+ progress = true;
+ break;
+
+ case nir_deref_type_cast:
+ if (opt_deref_cast(&b, deref))
+ progress = true;
+ break;
+
+ default:
+ /* Do nothing */
+ break;
+ }
+ }
+ }
+
+ if (progress) {
+ nir_metadata_preserve(impl, nir_metadata_block_index |
+ nir_metadata_dominance);
+ } else {
+ nir_metadata_preserve(impl, nir_metadata_all);
+ }
+
+ return progress;
+}
+
+bool
+nir_opt_deref(nir_shader *shader)
+{
+ bool progress = false;
+
+ nir_foreach_function(func, shader) {
+ if (func->impl && nir_opt_deref_impl(func->impl))
+ progress = true;
+ }
+
+ return progress;
+}
projects / mesa.git / blobdiff