#include "nir_deref.h"
struct var_info {
+ nir_variable *var;
+
bool is_constant;
bool found_read;
+ bool duplicate;
+
+ /* Block that has all the variable stores. All the blocks with reads
+ * should be dominated by this block.
+ */
+ nir_block *block;
+
+ /* If is_constant, hold the collected constant data for this var. */
+ uint32_t constant_data_size;
+ void *constant_data;
};
+static int
+var_info_cmp(const void *_a, const void *_b)
+{
+ const struct var_info *a = _a;
+ const struct var_info *b = _b;
+ uint32_t a_size = a->constant_data_size;
+ uint32_t b_size = b->constant_data_size;
+
+ if (a_size < b_size) {
+ return -1;
+ } else if (a_size > b_size) {
+ return 1;
+ } else if (a_size == 0) {
+ /* Don't call memcmp with invalid pointers. */
+ return 0;
+ } else {
+ return memcmp(a->constant_data, b->constant_data, a_size);
+ }
+}
+
static nir_ssa_def *
build_constant_load(nir_builder *b, nir_deref_instr *deref,
glsl_type_size_align_func size_align)
}
static void
-handle_constant_store(nir_builder *b, nir_intrinsic_instr *store,
+handle_constant_store(void *mem_ctx, struct var_info *info,
+ nir_deref_instr *deref, nir_const_value *val,
+ unsigned writemask,
glsl_type_size_align_func size_align)
{
- nir_deref_instr *deref = nir_src_as_deref(store->src[0]);
assert(!nir_deref_instr_has_indirect(deref));
-
- nir_variable *var = nir_deref_instr_get_variable(deref);
-
const unsigned bit_size = glsl_get_bit_size(deref->type);
const unsigned num_components = glsl_get_vector_elements(deref->type);
- char *dst = (char *)b->shader->constant_data +
- var->data.location +
+ if (info->constant_data_size == 0) {
+ unsigned var_size, var_align;
+ size_align(info->var->type, &var_size, &var_align);
+ info->constant_data_size = var_size;
+ info->constant_data = rzalloc_size(mem_ctx, var_size);
+ }
+
+ char *dst = (char *)info->constant_data +
nir_deref_instr_get_const_offset(deref, size_align);
- nir_const_value *val = nir_src_as_const_value(store->src[1]);
- switch (bit_size) {
- case 1:
- /* Booleans are special-cased to be 32-bit */
- for (unsigned i = 0; i < num_components; i++)
- ((int32_t *)dst)[i] = -(int)val->b[i];
- break;
-
- case 8:
- for (unsigned i = 0; i < num_components; i++)
- ((uint8_t *)dst)[i] = val->u8[i];
- break;
-
- case 16:
- for (unsigned i = 0; i < num_components; i++)
- ((uint16_t *)dst)[i] = val->u16[i];
- break;
-
- case 32:
- for (unsigned i = 0; i < num_components; i++)
- ((uint32_t *)dst)[i] = val->u32[i];
- break;
-
- case 64:
- for (unsigned i = 0; i < num_components; i++)
- ((uint64_t *)dst)[i] = val->u64[i];
- break;
-
- default:
- unreachable("Invalid bit size");
+ for (unsigned i = 0; i < num_components; i++) {
+ if (!(writemask & (1 << i)))
+ continue;
+
+ switch (bit_size) {
+ case 1:
+ /* Booleans are special-cased to be 32-bit */
+ ((int32_t *)dst)[i] = -(int)val[i].b;
+ break;
+
+ case 8:
+ ((uint8_t *)dst)[i] = val[i].u8;
+ break;
+
+ case 16:
+ ((uint16_t *)dst)[i] = val[i].u16;
+ break;
+
+ case 32:
+ ((uint32_t *)dst)[i] = val[i].u32;
+ break;
+
+ case 64:
+ ((uint64_t *)dst)[i] = val[i].u64;
+ break;
+
+ default:
+ unreachable("Invalid bit size");
+ }
}
}
/* This pass can only be run once */
assert(shader->constant_data == NULL && shader->constant_data_size == 0);
- /* The index parameter is unused for local variables so we'll use it for
- * indexing into our array of variable metadata.
- */
- unsigned num_locals = 0;
- nir_foreach_variable(var, &impl->locals)
- var->data.index = num_locals++;
+ unsigned num_locals = exec_list_length(&impl->locals);
+ nir_index_vars(shader, impl, nir_var_function_temp);
- struct var_info *var_infos = malloc(num_locals * sizeof(struct var_info));
- for (unsigned i = 0; i < num_locals; i++) {
- var_infos[i] = (struct var_info) {
+ if (num_locals == 0)
+ return false;
+
+ struct var_info *var_infos = ralloc_array(NULL, struct var_info, num_locals);
+ nir_foreach_variable(var, &impl->locals) {
+ var_infos[var->index] = (struct var_info) {
+ .var = var,
.is_constant = true,
.found_read = false,
};
}
+ nir_metadata_require(impl, nir_metadata_dominance);
+
/* First, walk through the shader and figure out what variables we can
* lower to the constant blob.
*/
- bool first_block = true;
nir_foreach_block(block, impl) {
nir_foreach_instr(instr, block) {
if (instr->type != nir_instr_type_intrinsic)
bool src_is_const = false;
nir_deref_instr *src_deref = NULL, *dst_deref = NULL;
+ unsigned writemask = 0;
switch (intrin->intrinsic) {
case nir_intrinsic_store_deref:
dst_deref = nir_src_as_deref(intrin->src[0]);
src_is_const = nir_src_is_const(intrin->src[1]);
+ writemask = nir_intrinsic_write_mask(intrin);
break;
case nir_intrinsic_load_deref:
break;
case nir_intrinsic_copy_deref:
- /* We always assume the src and therefore the dst are not
- * constants here. Copy and constant propagation passes should
- * have taken care of this in most cases anyway.
- */
- dst_deref = nir_src_as_deref(intrin->src[0]);
- src_deref = nir_src_as_deref(intrin->src[1]);
- src_is_const = false;
+ assert(!"Lowering of copy_deref with large constants is prohibited");
break;
default:
nir_variable *var = nir_deref_instr_get_variable(dst_deref);
assert(var->data.mode == nir_var_function_temp);
+ struct var_info *info = &var_infos[var->index];
+ if (!info->is_constant)
+ continue;
+
+ if (!info->block)
+ info->block = block;
+
/* We only consider variables constant if they only have constant
* stores, all the stores come before any reads, and all stores
- * come in the first block. We also can't handle indirect stores.
+ * come from the same block. We also can't handle indirect stores.
*/
- struct var_info *info = &var_infos[var->data.index];
- if (!src_is_const || info->found_read || !first_block ||
- nir_deref_instr_has_indirect(dst_deref))
+ if (!src_is_const || info->found_read || block != info->block ||
+ nir_deref_instr_has_indirect(dst_deref)) {
info->is_constant = false;
+ } else {
+ nir_const_value *val = nir_src_as_const_value(intrin->src[1]);
+ handle_constant_store(var_infos, info, dst_deref, val, writemask,
+ size_align);
+ }
}
if (src_deref && src_deref->mode == nir_var_function_temp) {
nir_variable *var = nir_deref_instr_get_variable(src_deref);
assert(var->data.mode == nir_var_function_temp);
- var_infos[var->data.index].found_read = true;
+ /* We only consider variables constant if all the reads are
+ * dominated by the block that writes to it.
+ */
+ struct var_info *info = &var_infos[var->index];
+ if (!info->is_constant)
+ continue;
+
+ if (!info->block || !nir_block_dominates(info->block, block))
+ info->is_constant = false;
+
+ info->found_read = true;
}
}
- first_block = false;
}
+ /* Allocate constant data space for each variable that just has constant
+ * data. We sort them by size and content so we can easily find
+ * duplicates.
+ */
shader->constant_data_size = 0;
- nir_foreach_variable(var, &impl->locals) {
- struct var_info *info = &var_infos[var->data.index];
+ qsort(var_infos, num_locals, sizeof(struct var_info), var_info_cmp);
+ for (int i = 0; i < num_locals; i++) {
+ struct var_info *info = &var_infos[i];
+
+ /* Fix up indices after we sorted. */
+ info->var->index = i;
+
if (!info->is_constant)
continue;
unsigned var_size, var_align;
- size_align(var->type, &var_size, &var_align);
+ size_align(info->var->type, &var_size, &var_align);
if (var_size <= threshold || !info->found_read) {
/* Don't bother lowering small stuff or data that's never read */
info->is_constant = false;
continue;
}
- var->data.location = ALIGN_POT(shader->constant_data_size, var_align);
- shader->constant_data_size = var->data.location + var_size;
+ if (i > 0 && var_info_cmp(info, &var_infos[i - 1]) == 0) {
+ info->var->data.location = var_infos[i - 1].var->data.location;
+ info->duplicate = true;
+ } else {
+ info->var->data.location = ALIGN_POT(shader->constant_data_size, var_align);
+ shader->constant_data_size = info->var->data.location + var_size;
+ }
}
if (shader->constant_data_size == 0) {
- free(var_infos);
+ ralloc_free(var_infos);
return false;
}
shader->constant_data = rzalloc_size(shader, shader->constant_data_size);
+ for (int i = 0; i < num_locals; i++) {
+ struct var_info *info = &var_infos[i];
+ if (!info->duplicate && info->is_constant) {
+ memcpy((char *)shader->constant_data + info->var->data.location,
+ info->constant_data, info->constant_data_size);
+ }
+ }
nir_builder b;
nir_builder_init(&b, impl);
continue;
nir_variable *var = nir_deref_instr_get_variable(deref);
- struct var_info *info = &var_infos[var->data.index];
+ struct var_info *info = &var_infos[var->index];
if (info->is_constant) {
b.cursor = nir_after_instr(&intrin->instr);
nir_ssa_def *val = build_constant_load(&b, deref, size_align);
continue;
nir_variable *var = nir_deref_instr_get_variable(deref);
- struct var_info *info = &var_infos[var->data.index];
+ struct var_info *info = &var_infos[var->index];
if (info->is_constant) {
- b.cursor = nir_after_instr(&intrin->instr);
- handle_constant_store(&b, intrin, size_align);
nir_instr_remove(&intrin->instr);
nir_deref_instr_remove_if_unused(deref);
}
break;
}
-
- case nir_intrinsic_copy_deref: {
- nir_deref_instr *deref = nir_src_as_deref(intrin->src[1]);
- if (deref->mode != nir_var_function_temp)
- continue;
-
- nir_variable *var = nir_deref_instr_get_variable(deref);
- struct var_info *info = &var_infos[var->data.index];
- if (info->is_constant) {
- b.cursor = nir_after_instr(&intrin->instr);
- nir_ssa_def *val = build_constant_load(&b, deref, size_align);
- nir_store_deref(&b, nir_src_as_deref(intrin->src[0]), val, ~0);
- nir_instr_remove(&intrin->instr);
- nir_deref_instr_remove_if_unused(deref);
- }
- break;
- }
-
+ case nir_intrinsic_copy_deref:
default:
continue;
}
}
/* Clean up the now unused variables */
- nir_foreach_variable_safe(var, &impl->locals) {
- if (var_infos[var->data.index].is_constant)
- exec_node_remove(&var->node);
+ for (int i = 0; i < num_locals; i++) {
+ struct var_info *info = &var_infos[i];
+ if (info->is_constant)
+ exec_node_remove(&info->var->node);
}
- free(var_infos);
+ ralloc_free(var_infos);
nir_metadata_preserve(impl, nir_metadata_block_index |
nir_metadata_dominance);