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Diffstat (limited to 'src/compiler/glsl/ir_set_program_inouts.cpp')
| -rw-r--r-- | src/compiler/glsl/ir_set_program_inouts.cpp | 453 |
1 files changed, 453 insertions, 0 deletions
diff --git a/src/compiler/glsl/ir_set_program_inouts.cpp b/src/compiler/glsl/ir_set_program_inouts.cpp new file mode 100644 index 00000000000..df06923b870 --- /dev/null +++ b/src/compiler/glsl/ir_set_program_inouts.cpp @@ -0,0 +1,453 @@ +/* + * Copyright © 2010 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 ir_set_program_inouts.cpp + * + * Sets the InputsRead and OutputsWritten of Mesa programs. + * + * Additionally, for fragment shaders, sets the InterpQualifier array, the + * IsCentroid and IsSample bitfields, and the UsesDFdy flag. + * + * Mesa programs (gl_program, not gl_shader_program) have a set of + * flags indicating which varyings are read and written. Computing + * which are actually read from some sort of backend code can be + * tricky when variable array indexing involved. So this pass + * provides support for setting InputsRead and OutputsWritten right + * from the GLSL IR. + */ + +#include "main/core.h" /* for struct gl_program */ +#include "ir.h" +#include "ir_visitor.h" +#include "compiler/glsl_types.h" + +namespace { + +class ir_set_program_inouts_visitor : public ir_hierarchical_visitor { +public: + ir_set_program_inouts_visitor(struct gl_program *prog, + gl_shader_stage shader_stage) + { + this->prog = prog; + this->shader_stage = shader_stage; + } + ~ir_set_program_inouts_visitor() + { + } + + virtual ir_visitor_status visit_enter(ir_dereference_array *); + virtual ir_visitor_status visit_enter(ir_function_signature *); + virtual ir_visitor_status visit_enter(ir_expression *); + virtual ir_visitor_status visit_enter(ir_discard *); + virtual ir_visitor_status visit_enter(ir_texture *); + virtual ir_visitor_status visit(ir_dereference_variable *); + +private: + void mark_whole_variable(ir_variable *var); + bool try_mark_partial_variable(ir_variable *var, ir_rvalue *index); + + struct gl_program *prog; + gl_shader_stage shader_stage; +}; + +} /* anonymous namespace */ + +static inline bool +is_shader_inout(ir_variable *var) +{ + return var->data.mode == ir_var_shader_in || + var->data.mode == ir_var_shader_out || + var->data.mode == ir_var_system_value; +} + +static void +mark(struct gl_program *prog, ir_variable *var, int offset, int len, + gl_shader_stage stage) +{ + /* As of GLSL 1.20, varyings can only be floats, floating-point + * vectors or matrices, or arrays of them. For Mesa programs using + * InputsRead/OutputsWritten, everything but matrices uses one + * slot, while matrices use a slot per column. Presumably + * something doing a more clever packing would use something other + * than InputsRead/OutputsWritten. + */ + + for (int i = 0; i < len; i++) { + int idx = var->data.location + var->data.index + offset + i; + bool is_patch_generic = var->data.patch && + idx != VARYING_SLOT_TESS_LEVEL_INNER && + idx != VARYING_SLOT_TESS_LEVEL_OUTER; + GLbitfield64 bitfield; + + if (is_patch_generic) { + assert(idx >= VARYING_SLOT_PATCH0 && idx < VARYING_SLOT_TESS_MAX); + bitfield = BITFIELD64_BIT(idx - VARYING_SLOT_PATCH0); + } + else { + assert(idx < VARYING_SLOT_MAX); + bitfield = BITFIELD64_BIT(idx); + } + + if (var->data.mode == ir_var_shader_in) { + if (is_patch_generic) + prog->PatchInputsRead |= bitfield; + else + prog->InputsRead |= bitfield; + + /* double inputs read is only for vertex inputs */ + if (stage == MESA_SHADER_VERTEX && + var->type->without_array()->is_dual_slot_double()) + prog->DoubleInputsRead |= bitfield; + + if (stage == MESA_SHADER_FRAGMENT) { + gl_fragment_program *fprog = (gl_fragment_program *) prog; + fprog->InterpQualifier[idx] = + (glsl_interp_qualifier) var->data.interpolation; + if (var->data.centroid) + fprog->IsCentroid |= bitfield; + if (var->data.sample) + fprog->IsSample |= bitfield; + } + } else if (var->data.mode == ir_var_system_value) { + prog->SystemValuesRead |= bitfield; + } else { + assert(var->data.mode == ir_var_shader_out); + if (is_patch_generic) + prog->PatchOutputsWritten |= bitfield; + else + prog->OutputsWritten |= bitfield; + } + } +} + +/** + * Mark an entire variable as used. Caller must ensure that the variable + * represents a shader input or output. + */ +void +ir_set_program_inouts_visitor::mark_whole_variable(ir_variable *var) +{ + const glsl_type *type = var->type; + bool vertex_input = false; + if (this->shader_stage == MESA_SHADER_GEOMETRY && + var->data.mode == ir_var_shader_in && type->is_array()) { + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_CTRL && + var->data.mode == ir_var_shader_in) { + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_CTRL && + var->data.mode == ir_var_shader_out && !var->data.patch) { + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_EVAL && + var->data.mode == ir_var_shader_in && !var->data.patch) { + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_VERTEX && + var->data.mode == ir_var_shader_in) + vertex_input = true; + + mark(this->prog, var, 0, type->count_attribute_slots(vertex_input), + this->shader_stage); +} + +/* Default handler: Mark all the locations in the variable as used. */ +ir_visitor_status +ir_set_program_inouts_visitor::visit(ir_dereference_variable *ir) +{ + if (!is_shader_inout(ir->var)) + return visit_continue; + + mark_whole_variable(ir->var); + + return visit_continue; +} + +/** + * Try to mark a portion of the given variable as used. Caller must ensure + * that the variable represents a shader input or output which can be indexed + * into in array fashion (an array or matrix). For the purpose of geometry + * shader inputs (which are always arrays*), this means that the array element + * must be something that can be indexed into in array fashion. + * + * *Except gl_PrimitiveIDIn, as noted below. + * + * For tessellation control shaders all inputs and non-patch outputs are + * arrays. For tessellation evaluation shaders non-patch inputs are arrays. + * + * If the index can't be interpreted as a constant, or some other problem + * occurs, then nothing will be marked and false will be returned. + */ +bool +ir_set_program_inouts_visitor::try_mark_partial_variable(ir_variable *var, + ir_rvalue *index) +{ + const glsl_type *type = var->type; + + if (this->shader_stage == MESA_SHADER_GEOMETRY && + var->data.mode == ir_var_shader_in) { + /* The only geometry shader input that is not an array is + * gl_PrimitiveIDIn, and in that case, this code will never be reached, + * because gl_PrimitiveIDIn can't be indexed into in array fashion. + */ + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_CTRL && + var->data.mode == ir_var_shader_in) { + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_CTRL && + var->data.mode == ir_var_shader_out && !var->data.patch) { + assert(type->is_array()); + type = type->fields.array; + } + + if (this->shader_stage == MESA_SHADER_TESS_EVAL && + var->data.mode == ir_var_shader_in && !var->data.patch) { + assert(type->is_array()); + type = type->fields.array; + } + + /* TODO: implement proper arrays of arrays support + * for now let the caller mark whole variable as used. + */ + if (type->is_array() && type->fields.array->is_array()) + return false; + + /* The code below only handles: + * + * - Indexing into matrices + * - Indexing into arrays of (matrices, vectors, or scalars) + * + * All other possibilities are either prohibited by GLSL (vertex inputs and + * fragment outputs can't be structs) or should have been eliminated by + * lowering passes (do_vec_index_to_swizzle() gets rid of indexing into + * vectors, and lower_packed_varyings() gets rid of structs that occur in + * varyings). + */ + if (!(type->is_matrix() || + (type->is_array() && + (type->fields.array->is_numeric() || + type->fields.array->is_boolean())))) { + assert(!"Unexpected indexing in ir_set_program_inouts"); + + /* For safety in release builds, in case we ever encounter unexpected + * indexing, give up and let the caller mark the whole variable as used. + */ + return false; + } + + ir_constant *index_as_constant = index->as_constant(); + if (!index_as_constant) + return false; + + unsigned elem_width; + unsigned num_elems; + if (type->is_array()) { + num_elems = type->length; + if (type->fields.array->is_matrix()) + elem_width = type->fields.array->matrix_columns; + else + elem_width = 1; + } else { + num_elems = type->matrix_columns; + elem_width = 1; + } + + if (index_as_constant->value.u[0] >= num_elems) { + /* Constant index outside the bounds of the matrix/array. This could + * arise as a result of constant folding of a legal GLSL program. + * + * Even though the spec says that indexing outside the bounds of a + * matrix/array results in undefined behaviour, we don't want to pass + * out-of-range values to mark() (since this could result in slots that + * don't exist being marked as used), so just let the caller mark the + * whole variable as used. + */ + return false; + } + + /* double element width for double types that takes two slots */ + if (this->shader_stage != MESA_SHADER_VERTEX || + var->data.mode != ir_var_shader_in) { + if (type->without_array()->is_dual_slot_double()) + elem_width *= 2; + } + + mark(this->prog, var, index_as_constant->value.u[0] * elem_width, + elem_width, this->shader_stage); + return true; +} + +static bool +is_multiple_vertices(gl_shader_stage stage, ir_variable *var) +{ + if (var->data.patch) + return false; + + if (var->data.mode == ir_var_shader_in) + return stage == MESA_SHADER_GEOMETRY || + stage == MESA_SHADER_TESS_CTRL || + stage == MESA_SHADER_TESS_EVAL; + if (var->data.mode == ir_var_shader_out) + return stage == MESA_SHADER_TESS_CTRL; + + return false; +} + +ir_visitor_status +ir_set_program_inouts_visitor::visit_enter(ir_dereference_array *ir) +{ + /* Note: for geometry shader inputs, lower_named_interface_blocks may + * create 2D arrays, so we need to be able to handle those. 2D arrays + * shouldn't be able to crop up for any other reason. + */ + if (ir_dereference_array * const inner_array = + ir->array->as_dereference_array()) { + /* ir => foo[i][j] + * inner_array => foo[i] + */ + if (ir_dereference_variable * const deref_var = + inner_array->array->as_dereference_variable()) { + if (is_multiple_vertices(this->shader_stage, deref_var->var)) { + /* foo is a geometry or tessellation shader input, so i is + * the vertex, and j the part of the input we're accessing. + */ + if (try_mark_partial_variable(deref_var->var, ir->array_index)) + { + /* We've now taken care of foo and j, but i might contain a + * subexpression that accesses shader inputs. So manually + * visit i and then continue with the parent. + */ + inner_array->array_index->accept(this); + return visit_continue_with_parent; + } + } + } + } else if (ir_dereference_variable * const deref_var = + ir->array->as_dereference_variable()) { + /* ir => foo[i], where foo is a variable. */ + if (is_multiple_vertices(this->shader_stage, deref_var->var)) { + /* foo is a geometry or tessellation shader input, so i is + * the vertex, and we're accessing the entire input. + */ + mark_whole_variable(deref_var->var); + /* We've now taken care of foo, but i might contain a subexpression + * that accesses shader inputs. So manually visit i and then + * continue with the parent. + */ + ir->array_index->accept(this); + return visit_continue_with_parent; + } else if (is_shader_inout(deref_var->var)) { + /* foo is a shader input/output, but not a geometry shader input, + * so i is the part of the input we're accessing. + */ + if (try_mark_partial_variable(deref_var->var, ir->array_index)) + return visit_continue_with_parent; + } + } + + /* The expression is something we don't recognize. Just visit its + * subexpressions. + */ + return visit_continue; +} + +ir_visitor_status +ir_set_program_inouts_visitor::visit_enter(ir_function_signature *ir) +{ + /* We don't want to descend into the function parameters and + * consider them as shader inputs or outputs. + */ + visit_list_elements(this, &ir->body); + return visit_continue_with_parent; +} + +ir_visitor_status +ir_set_program_inouts_visitor::visit_enter(ir_expression *ir) +{ + if (this->shader_stage == MESA_SHADER_FRAGMENT && + (ir->operation == ir_unop_dFdy || + ir->operation == ir_unop_dFdy_coarse || + ir->operation == ir_unop_dFdy_fine)) { + gl_fragment_program *fprog = (gl_fragment_program *) prog; + fprog->UsesDFdy = true; + } + return visit_continue; +} + +ir_visitor_status +ir_set_program_inouts_visitor::visit_enter(ir_discard *) +{ + /* discards are only allowed in fragment shaders. */ + assert(this->shader_stage == MESA_SHADER_FRAGMENT); + + gl_fragment_program *fprog = (gl_fragment_program *) prog; + fprog->UsesKill = true; + + return visit_continue; +} + +ir_visitor_status +ir_set_program_inouts_visitor::visit_enter(ir_texture *ir) +{ + if (ir->op == ir_tg4) + prog->UsesGather = true; + return visit_continue; +} + +void +do_set_program_inouts(exec_list *instructions, struct gl_program *prog, + gl_shader_stage shader_stage) +{ + ir_set_program_inouts_visitor v(prog, shader_stage); + + prog->InputsRead = 0; + prog->OutputsWritten = 0; + prog->PatchInputsRead = 0; + prog->PatchOutputsWritten = 0; + prog->SystemValuesRead = 0; + if (shader_stage == MESA_SHADER_FRAGMENT) { + gl_fragment_program *fprog = (gl_fragment_program *) prog; + memset(fprog->InterpQualifier, 0, sizeof(fprog->InterpQualifier)); + fprog->IsCentroid = 0; + fprog->IsSample = 0; + fprog->UsesDFdy = false; + fprog->UsesKill = false; + } + visit_list_elements(&v, instructions); +} |