diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/glsl/Makefile.sources | 1 | ||||
| -rw-r--r-- | src/glsl/ir_optimization.h | 1 | ||||
| -rw-r--r-- | src/glsl/lower_ubo_reference.cpp | 313 |
3 files changed, 315 insertions, 0 deletions
diff --git a/src/glsl/Makefile.sources b/src/glsl/Makefile.sources index f2743f75067..765f06a27cb 100644 --- a/src/glsl/Makefile.sources +++ b/src/glsl/Makefile.sources @@ -66,6 +66,7 @@ LIBGLSL_CXX_FILES = \ $(GLSL_SRCDIR)/lower_vec_index_to_swizzle.cpp \ $(GLSL_SRCDIR)/lower_vector.cpp \ $(GLSL_SRCDIR)/lower_output_reads.cpp \ + $(GLSL_SRCDIR)/lower_ubo_reference.cpp \ $(GLSL_SRCDIR)/opt_algebraic.cpp \ $(GLSL_SRCDIR)/opt_array_splitting.cpp \ $(GLSL_SRCDIR)/opt_constant_folding.cpp \ diff --git a/src/glsl/ir_optimization.h b/src/glsl/ir_optimization.h index c435d771726..2220d511e96 100644 --- a/src/glsl/ir_optimization.h +++ b/src/glsl/ir_optimization.h @@ -74,6 +74,7 @@ bool lower_variable_index_to_cond_assign(exec_list *instructions, bool lower_quadop_vector(exec_list *instructions, bool dont_lower_swz); bool lower_clip_distance(exec_list *instructions); void lower_output_reads(exec_list *instructions); +void lower_ubo_reference(struct gl_shader *shader, exec_list *instructions); bool optimize_redundant_jumps(exec_list *instructions); bool optimize_split_arrays(exec_list *instructions, bool linked); diff --git a/src/glsl/lower_ubo_reference.cpp b/src/glsl/lower_ubo_reference.cpp new file mode 100644 index 00000000000..e8d2c4742d6 --- /dev/null +++ b/src/glsl/lower_ubo_reference.cpp @@ -0,0 +1,313 @@ +/* + * Copyright © 2012 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER + * DEALINGS IN THE SOFTWARE. + */ + +/** + * \file lower_ubo_reference.cpp + * + * IR lower pass to replace dereferences of variables in a uniform + * buffer object with usage of ir_binop_ubo_load expressions, each of + * which can read data up to the size of a vec4. + * + * This relieves drivers of the responsibility to deal with tricky UBO + * layout issues like std140 structures and row_major matrices on + * their own. + */ + +#include "ir.h" +#include "ir_builder.h" +#include "ir_rvalue_visitor.h" +#include "main/macros.h" + +using namespace ir_builder; + +namespace { +class lower_ubo_reference_visitor : public ir_rvalue_enter_visitor { +public: + lower_ubo_reference_visitor(struct gl_shader *shader) + : shader(shader) + { + } + + void handle_rvalue(ir_rvalue **rvalue); + void emit_ubo_loads(ir_dereference *deref, ir_variable *base_offset, + unsigned int deref_offset); + ir_expression *ubo_load(const struct glsl_type *type, + ir_rvalue *offset); + + void *mem_ctx; + struct gl_shader *shader; + struct gl_uniform_buffer_variable *ubo_var; + unsigned uniform_block; + bool progress; +}; + +static inline unsigned int +align(unsigned int a, unsigned int align) +{ + return (a + align - 1) / align * align; +} + +void +lower_ubo_reference_visitor::handle_rvalue(ir_rvalue **rvalue) +{ + if (!*rvalue) + return; + + ir_dereference *deref = (*rvalue)->as_dereference(); + if (!deref) + return; + + ir_variable *var = deref->variable_referenced(); + if (!var || var->uniform_block == -1) + return; + + mem_ctx = ralloc_parent(*rvalue); + uniform_block = var->uniform_block; + struct gl_uniform_block *block = &shader->UniformBlocks[uniform_block]; + this->ubo_var = &block->Uniforms[var->location]; + ir_rvalue *offset = new(mem_ctx) ir_constant(0u); + unsigned const_offset = 0; + bool row_major = ubo_var->RowMajor; + + /* Calculate the offset to the start of the region of the UBO + * dereferenced by *rvalue. This may be a variable offset if an + * array dereference has a variable index. + */ + while (deref) { + switch (deref->ir_type) { + case ir_type_dereference_variable: { + const_offset += ubo_var->Offset; + deref = NULL; + break; + } + + case ir_type_dereference_array: { + ir_dereference_array *deref_array = (ir_dereference_array *)deref; + unsigned array_stride; + if (deref_array->array->type->is_matrix() && row_major) { + /* When loading a vector out of a row major matrix, the + * step between the columns (vectors) is the size of a + * float, while the step between the rows (elements of a + * vector) is handled below in emit_ubo_loads. + */ + array_stride = 4; + } else { + array_stride = deref_array->type->std140_size(row_major); + array_stride = align(array_stride, 16); + } + + ir_constant *const_index = deref_array->array_index->as_constant(); + if (const_index) { + const_offset += array_stride * const_index->value.i[0]; + } else { + offset = add(offset, + mul(deref_array->array_index, + new(mem_ctx) ir_constant(array_stride))); + } + deref = deref_array->array->as_dereference(); + break; + } + + case ir_type_dereference_record: { + ir_dereference_record *deref_record = (ir_dereference_record *)deref; + const glsl_type *struct_type = deref_record->record->type; + unsigned intra_struct_offset = 0; + + unsigned max_field_align = 16; + for (unsigned int i = 0; i < struct_type->length; i++) { + const glsl_type *type = struct_type->fields.structure[i].type; + unsigned field_align = type->std140_base_alignment(row_major); + max_field_align = MAX2(field_align, max_field_align); + intra_struct_offset = align(intra_struct_offset, field_align); + + if (strcmp(struct_type->fields.structure[i].name, + deref_record->field) == 0) + break; + intra_struct_offset += type->std140_size(row_major); + } + + const_offset = align(const_offset, max_field_align); + const_offset += intra_struct_offset; + + deref = deref_record->record->as_dereference(); + break; + } + default: + assert(!"not reached"); + deref = NULL; + break; + } + } + + /* Now that we've calculated the offset to the start of the + * dereference, walk over the type and emit loads into a temporary. + */ + const glsl_type *type = (*rvalue)->type; + ir_variable *load_var = new(mem_ctx) ir_variable(type, + "ubo_load_temp", + ir_var_temporary); + base_ir->insert_before(load_var); + + ir_variable *load_offset = new(mem_ctx) ir_variable(glsl_type::uint_type, + "ubo_load_temp_offset", + ir_var_temporary); + base_ir->insert_before(load_offset); + base_ir->insert_before(assign(load_offset, offset)); + + deref = new(mem_ctx) ir_dereference_variable(load_var); + emit_ubo_loads(deref, load_offset, const_offset); + *rvalue = deref; + + progress = true; +} + +ir_expression * +lower_ubo_reference_visitor::ubo_load(const glsl_type *type, + ir_rvalue *offset) +{ + return new(mem_ctx) + ir_expression(ir_binop_ubo_load, + type, + new(mem_ctx) ir_constant(this->uniform_block), + offset); + +} + +/** + * Takes LHS and emits a series of assignments into its components + * from the UBO variable at variable_offset + deref_offset. + * + * Recursively calls itself to break the deref down to the point that + * the ir_binop_ubo_load expressions generated are contiguous scalars + * or vectors. + */ +void +lower_ubo_reference_visitor::emit_ubo_loads(ir_dereference *deref, + ir_variable *base_offset, + unsigned int deref_offset) +{ + if (deref->type->is_record()) { + unsigned int field_offset = 0; + + for (unsigned i = 0; i < deref->type->length; i++) { + const struct glsl_struct_field *field = + &deref->type->fields.structure[i]; + ir_dereference *field_deref = + new(mem_ctx) ir_dereference_record(deref->clone(mem_ctx, NULL), + field->name); + + field_offset = + align(field_offset, + field->type->std140_base_alignment(ubo_var->RowMajor)); + + emit_ubo_loads(field_deref, base_offset, deref_offset + field_offset); + + field_offset += field->type->std140_size(ubo_var->RowMajor); + } + return; + } + + if (deref->type->is_array()) { + unsigned array_stride = + align(deref->type->fields.array->std140_size(ubo_var->RowMajor), 16); + + for (unsigned i = 0; i < deref->type->length; i++) { + ir_constant *element = new(mem_ctx) ir_constant(i); + ir_dereference *element_deref = + new(mem_ctx) ir_dereference_array(deref->clone(mem_ctx, NULL), + element); + emit_ubo_loads(element_deref, base_offset, + deref_offset + i * array_stride); + } + return; + } + + if (deref->type->is_matrix()) { + for (unsigned i = 0; i < deref->type->matrix_columns; i++) { + ir_constant *col = new(mem_ctx) ir_constant(i); + ir_dereference *col_deref = + new(mem_ctx) ir_dereference_array(deref->clone(mem_ctx, NULL), + col); + + /* std140 always rounds the stride of arrays (and matrices) + * to a vec4, so matrices are always 16 between columns/rows. + */ + emit_ubo_loads(col_deref, base_offset, deref_offset + i * 16); + } + return; + } + + assert(deref->type->is_scalar() || + deref->type->is_vector()); + + if (!ubo_var->RowMajor) { + ir_rvalue *offset = add(base_offset, + new(mem_ctx) ir_constant(deref_offset)); + base_ir->insert_before(assign(deref->clone(mem_ctx, NULL), + ubo_load(deref->type, offset))); + } else { + /* We're dereffing a column out of a row-major matrix, so we + * gather the vector from each stored row. + */ + assert(deref->type->base_type == GLSL_TYPE_FLOAT); + /* Matrices, row_major or not, are stored as if they were + * arrays of vectors of the appropriate size in std140. + * Arrays have their strides rounded up to a vec4, so the + * matrix stride is always 16. + */ + unsigned matrix_stride = 16; + + for (unsigned i = 0; i < deref->type->vector_elements; i++) { + ir_rvalue *chan = new(mem_ctx) ir_constant((int)i); + ir_dereference *deref_chan = + new(mem_ctx) ir_dereference_array(deref->clone(mem_ctx, NULL), + chan); + + ir_rvalue *chan_offset = + add(base_offset, + new(mem_ctx) ir_constant(deref_offset + i * matrix_stride)); + + base_ir->insert_before(assign(deref_chan, + ubo_load(glsl_type::float_type, + chan_offset))); + } + } +} + +} /* unnamed namespace */ + +void +lower_ubo_reference(struct gl_shader *shader, exec_list *instructions) +{ + lower_ubo_reference_visitor v(shader); + + /* Loop over the instructions lowering references, because we take + * a deref of a UBO array using a UBO dereference as the index will + * produce a collection of instructions all of which have cloned + * UBO dereferences for that array index. + */ + do { + v.progress = false; + visit_list_elements(&v, instructions); + } while (v.progress); +} |