#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,
nir_deref_instr *deref, void *mem_ctx)
*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);
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);
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)
{
- assert(deref->deref_type == nir_deref_type_ptr_as_array);
- nir_deref_instr *parent = nir_deref_instr_parent(deref);
- switch (parent->deref_type) {
+ switch (deref->deref_type) {
case nir_deref_type_array:
- return glsl_get_explicit_stride(nir_deref_instr_parent(parent)->type);
+ 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(parent);
+ return nir_deref_instr_ptr_as_array_stride(nir_deref_instr_parent(deref));
case nir_deref_type_cast:
- return parent->cast.ptr_stride;
+ return deref->cast.ptr_stride;
default:
- unreachable("Invalid parent for ptr_as_array deref");
+ return 0;
}
}
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) {
+ 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");
}
}
static bool
modes_may_alias(nir_variable_mode a, nir_variable_mode b)
{
- /* Two pointers can only alias if they have the same mode.
+ /* 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,
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)
return nir_derefs_may_alias_bit;
if (a_path->path[0]->deref_type == nir_deref_type_var) {
- /* If we can chase the deref all the way back to the variable and
- * they're not the same variable, we know they can't possibly alias.
- */
- if (a_path->path[0]->var != b_path->path[0]->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
}
/* We're at either the tail or the divergence point between the two deref
- * paths. Look to see if either contains a ptr_as_array deref. It it
- * does we don't know how to safely make any inferences. Hopefully,
+ * 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.
*
* different constant indices.
*/
for (nir_deref_instr **t_p = a_p; *t_p; t_p++) {
- if ((*t_p)->deref_type == nir_deref_type_ptr_as_array)
+ 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_ptr_as_array)
+ 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;
}
return deref;
if (!state->cache) {
- state->cache = _mesa_hash_table_create(NULL, _mesa_hash_pointer,
- _mesa_key_pointer_equal);
+ state->cache = _mesa_pointer_hash_table_create(NULL);
}
struct hash_entry *cached = _mesa_hash_table_search(state->cache, deref);
switch (deref->deref_type) {
case nir_deref_type_var:
case nir_deref_type_array_wildcard:
- case nir_deref_type_cast:
/* 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;
* 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)
_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));
+ 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);
return state.progress;
}
-static bool
-is_trivial_deref_cast(nir_deref_instr *cast)
+static void
+nir_deref_instr_fixup_child_types(nir_deref_instr *parent)
{
- nir_deref_instr *parent = nir_src_as_deref(cast->parent);
- if (!parent)
- return false;
+ nir_foreach_use(use, &parent->dest.ssa) {
+ if (use->parent_instr->type != nir_instr_type_deref)
+ continue;
- 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;
+ 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
nir_instr_as_deref(instr)->deref_type == nir_deref_type_ptr_as_array;
}
+/**
+ * Remove casts that just wrap other casts.
+ */
static bool
-opt_deref_cast(nir_deref_instr *cast)
+opt_remove_cast_cast(nir_deref_instr *cast)
{
- if (!is_trivial_deref_cast(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);
- bool progress = false;
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 uses would be a bit crazy */
- assert(list_empty(&cast->dest.ssa.if_uses));
+ assert(list_is_empty(&cast->dest.ssa.if_uses));
+
+ if (nir_deref_instr_remove_if_unused(cast))
+ progress = true;
- nir_deref_instr_remove_if_unused(cast);
return progress;
}
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;
return true;
}
-static bool
+bool
nir_opt_deref_impl(nir_function_impl *impl)
{
bool progress = false;
break;
case nir_deref_type_cast:
- if (opt_deref_cast(deref))
+ if (opt_deref_cast(&b, deref))
progress = true;
break;
if (progress) {
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);
+ } else {
+ nir_metadata_preserve(impl, nir_metadata_all);
}
return progress;