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Diffstat (limited to 'src/compiler/glsl/linker.cpp')
| -rw-r--r-- | src/compiler/glsl/linker.cpp | 4676 |
1 files changed, 4676 insertions, 0 deletions
diff --git a/src/compiler/glsl/linker.cpp b/src/compiler/glsl/linker.cpp new file mode 100644 index 00000000000..6657777d74c --- /dev/null +++ b/src/compiler/glsl/linker.cpp @@ -0,0 +1,4676 @@ +/* + * 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 linker.cpp + * GLSL linker implementation + * + * Given a set of shaders that are to be linked to generate a final program, + * there are three distinct stages. + * + * In the first stage shaders are partitioned into groups based on the shader + * type. All shaders of a particular type (e.g., vertex shaders) are linked + * together. + * + * - Undefined references in each shader are resolve to definitions in + * another shader. + * - Types and qualifiers of uniforms, outputs, and global variables defined + * in multiple shaders with the same name are verified to be the same. + * - Initializers for uniforms and global variables defined + * in multiple shaders with the same name are verified to be the same. + * + * The result, in the terminology of the GLSL spec, is a set of shader + * executables for each processing unit. + * + * After the first stage is complete, a series of semantic checks are performed + * on each of the shader executables. + * + * - Each shader executable must define a \c main function. + * - Each vertex shader executable must write to \c gl_Position. + * - Each fragment shader executable must write to either \c gl_FragData or + * \c gl_FragColor. + * + * In the final stage individual shader executables are linked to create a + * complete exectuable. + * + * - Types of uniforms defined in multiple shader stages with the same name + * are verified to be the same. + * - Initializers for uniforms defined in multiple shader stages with the + * same name are verified to be the same. + * - Types and qualifiers of outputs defined in one stage are verified to + * be the same as the types and qualifiers of inputs defined with the same + * name in a later stage. + * + * \author Ian Romanick <[email protected]> + */ + +#include <ctype.h> +#include "util/strndup.h" +#include "main/core.h" +#include "glsl_symbol_table.h" +#include "glsl_parser_extras.h" +#include "ir.h" +#include "program.h" +#include "program/hash_table.h" +#include "linker.h" +#include "link_varyings.h" +#include "ir_optimization.h" +#include "ir_rvalue_visitor.h" +#include "ir_uniform.h" + +#include "main/shaderobj.h" +#include "main/enums.h" + + +void linker_error(gl_shader_program *, const char *, ...); + +namespace { + +/** + * Visitor that determines whether or not a variable is ever written. + */ +class find_assignment_visitor : public ir_hierarchical_visitor { +public: + find_assignment_visitor(const char *name) + : name(name), found(false) + { + /* empty */ + } + + virtual ir_visitor_status visit_enter(ir_assignment *ir) + { + ir_variable *const var = ir->lhs->variable_referenced(); + + if (strcmp(name, var->name) == 0) { + found = true; + return visit_stop; + } + + return visit_continue_with_parent; + } + + virtual ir_visitor_status visit_enter(ir_call *ir) + { + foreach_two_lists(formal_node, &ir->callee->parameters, + actual_node, &ir->actual_parameters) { + ir_rvalue *param_rval = (ir_rvalue *) actual_node; + ir_variable *sig_param = (ir_variable *) formal_node; + + if (sig_param->data.mode == ir_var_function_out || + sig_param->data.mode == ir_var_function_inout) { + ir_variable *var = param_rval->variable_referenced(); + if (var && strcmp(name, var->name) == 0) { + found = true; + return visit_stop; + } + } + } + + if (ir->return_deref != NULL) { + ir_variable *const var = ir->return_deref->variable_referenced(); + + if (strcmp(name, var->name) == 0) { + found = true; + return visit_stop; + } + } + + return visit_continue_with_parent; + } + + bool variable_found() + { + return found; + } + +private: + const char *name; /**< Find writes to a variable with this name. */ + bool found; /**< Was a write to the variable found? */ +}; + + +/** + * Visitor that determines whether or not a variable is ever read. + */ +class find_deref_visitor : public ir_hierarchical_visitor { +public: + find_deref_visitor(const char *name) + : name(name), found(false) + { + /* empty */ + } + + virtual ir_visitor_status visit(ir_dereference_variable *ir) + { + if (strcmp(this->name, ir->var->name) == 0) { + this->found = true; + return visit_stop; + } + + return visit_continue; + } + + bool variable_found() const + { + return this->found; + } + +private: + const char *name; /**< Find writes to a variable with this name. */ + bool found; /**< Was a write to the variable found? */ +}; + + +class geom_array_resize_visitor : public ir_hierarchical_visitor { +public: + unsigned num_vertices; + gl_shader_program *prog; + + geom_array_resize_visitor(unsigned num_vertices, gl_shader_program *prog) + { + this->num_vertices = num_vertices; + this->prog = prog; + } + + virtual ~geom_array_resize_visitor() + { + /* empty */ + } + + virtual ir_visitor_status visit(ir_variable *var) + { + if (!var->type->is_array() || var->data.mode != ir_var_shader_in) + return visit_continue; + + unsigned size = var->type->length; + + /* Generate a link error if the shader has declared this array with an + * incorrect size. + */ + if (size && size != this->num_vertices) { + linker_error(this->prog, "size of array %s declared as %u, " + "but number of input vertices is %u\n", + var->name, size, this->num_vertices); + return visit_continue; + } + + /* Generate a link error if the shader attempts to access an input + * array using an index too large for its actual size assigned at link + * time. + */ + if (var->data.max_array_access >= this->num_vertices) { + linker_error(this->prog, "geometry shader accesses element %i of " + "%s, but only %i input vertices\n", + var->data.max_array_access, var->name, this->num_vertices); + return visit_continue; + } + + var->type = glsl_type::get_array_instance(var->type->fields.array, + this->num_vertices); + var->data.max_array_access = this->num_vertices - 1; + + return visit_continue; + } + + /* Dereferences of input variables need to be updated so that their type + * matches the newly assigned type of the variable they are accessing. */ + virtual ir_visitor_status visit(ir_dereference_variable *ir) + { + ir->type = ir->var->type; + return visit_continue; + } + + /* Dereferences of 2D input arrays need to be updated so that their type + * matches the newly assigned type of the array they are accessing. */ + virtual ir_visitor_status visit_leave(ir_dereference_array *ir) + { + const glsl_type *const vt = ir->array->type; + if (vt->is_array()) + ir->type = vt->fields.array; + return visit_continue; + } +}; + +class tess_eval_array_resize_visitor : public ir_hierarchical_visitor { +public: + unsigned num_vertices; + gl_shader_program *prog; + + tess_eval_array_resize_visitor(unsigned num_vertices, gl_shader_program *prog) + { + this->num_vertices = num_vertices; + this->prog = prog; + } + + virtual ~tess_eval_array_resize_visitor() + { + /* empty */ + } + + virtual ir_visitor_status visit(ir_variable *var) + { + if (!var->type->is_array() || var->data.mode != ir_var_shader_in || var->data.patch) + return visit_continue; + + var->type = glsl_type::get_array_instance(var->type->fields.array, + this->num_vertices); + var->data.max_array_access = this->num_vertices - 1; + + return visit_continue; + } + + /* Dereferences of input variables need to be updated so that their type + * matches the newly assigned type of the variable they are accessing. */ + virtual ir_visitor_status visit(ir_dereference_variable *ir) + { + ir->type = ir->var->type; + return visit_continue; + } + + /* Dereferences of 2D input arrays need to be updated so that their type + * matches the newly assigned type of the array they are accessing. */ + virtual ir_visitor_status visit_leave(ir_dereference_array *ir) + { + const glsl_type *const vt = ir->array->type; + if (vt->is_array()) + ir->type = vt->fields.array; + return visit_continue; + } +}; + +class barrier_use_visitor : public ir_hierarchical_visitor { +public: + barrier_use_visitor(gl_shader_program *prog) + : prog(prog), in_main(false), after_return(false), control_flow(0) + { + } + + virtual ~barrier_use_visitor() + { + /* empty */ + } + + virtual ir_visitor_status visit_enter(ir_function *ir) + { + if (strcmp(ir->name, "main") == 0) + in_main = true; + + return visit_continue; + } + + virtual ir_visitor_status visit_leave(ir_function *) + { + in_main = false; + after_return = false; + return visit_continue; + } + + virtual ir_visitor_status visit_leave(ir_return *) + { + after_return = true; + return visit_continue; + } + + virtual ir_visitor_status visit_enter(ir_if *) + { + ++control_flow; + return visit_continue; + } + + virtual ir_visitor_status visit_leave(ir_if *) + { + --control_flow; + return visit_continue; + } + + virtual ir_visitor_status visit_enter(ir_loop *) + { + ++control_flow; + return visit_continue; + } + + virtual ir_visitor_status visit_leave(ir_loop *) + { + --control_flow; + return visit_continue; + } + + /* FINISHME: `switch` is not expressed at the IR level -- it's already + * been lowered to a mess of `if`s. We'll correctly disallow any use of + * barrier() in a conditional path within the switch, but not in a path + * which is always hit. + */ + + virtual ir_visitor_status visit_enter(ir_call *ir) + { + if (ir->use_builtin && strcmp(ir->callee_name(), "barrier") == 0) { + /* Use of barrier(); determine if it is legal: */ + if (!in_main) { + linker_error(prog, "Builtin barrier() may only be used in main"); + return visit_stop; + } + + if (after_return) { + linker_error(prog, "Builtin barrier() may not be used after return"); + return visit_stop; + } + + if (control_flow != 0) { + linker_error(prog, "Builtin barrier() may not be used inside control flow"); + return visit_stop; + } + } + return visit_continue; + } + +private: + gl_shader_program *prog; + bool in_main, after_return; + int control_flow; +}; + +/** + * Visitor that determines the highest stream id to which a (geometry) shader + * emits vertices. It also checks whether End{Stream}Primitive is ever called. + */ +class find_emit_vertex_visitor : public ir_hierarchical_visitor { +public: + find_emit_vertex_visitor(int max_allowed) + : max_stream_allowed(max_allowed), + invalid_stream_id(0), + invalid_stream_id_from_emit_vertex(false), + end_primitive_found(false), + uses_non_zero_stream(false) + { + /* empty */ + } + + virtual ir_visitor_status visit_leave(ir_emit_vertex *ir) + { + int stream_id = ir->stream_id(); + + if (stream_id < 0) { + invalid_stream_id = stream_id; + invalid_stream_id_from_emit_vertex = true; + return visit_stop; + } + + if (stream_id > max_stream_allowed) { + invalid_stream_id = stream_id; + invalid_stream_id_from_emit_vertex = true; + return visit_stop; + } + + if (stream_id != 0) + uses_non_zero_stream = true; + + return visit_continue; + } + + virtual ir_visitor_status visit_leave(ir_end_primitive *ir) + { + end_primitive_found = true; + + int stream_id = ir->stream_id(); + + if (stream_id < 0) { + invalid_stream_id = stream_id; + invalid_stream_id_from_emit_vertex = false; + return visit_stop; + } + + if (stream_id > max_stream_allowed) { + invalid_stream_id = stream_id; + invalid_stream_id_from_emit_vertex = false; + return visit_stop; + } + + if (stream_id != 0) + uses_non_zero_stream = true; + + return visit_continue; + } + + bool error() + { + return invalid_stream_id != 0; + } + + const char *error_func() + { + return invalid_stream_id_from_emit_vertex ? + "EmitStreamVertex" : "EndStreamPrimitive"; + } + + int error_stream() + { + return invalid_stream_id; + } + + bool uses_streams() + { + return uses_non_zero_stream; + } + + bool uses_end_primitive() + { + return end_primitive_found; + } + +private: + int max_stream_allowed; + int invalid_stream_id; + bool invalid_stream_id_from_emit_vertex; + bool end_primitive_found; + bool uses_non_zero_stream; +}; + +/* Class that finds array derefs and check if indexes are dynamic. */ +class dynamic_sampler_array_indexing_visitor : public ir_hierarchical_visitor +{ +public: + dynamic_sampler_array_indexing_visitor() : + dynamic_sampler_array_indexing(false) + { + } + + ir_visitor_status visit_enter(ir_dereference_array *ir) + { + if (!ir->variable_referenced()) + return visit_continue; + + if (!ir->variable_referenced()->type->contains_sampler()) + return visit_continue; + + if (!ir->array_index->constant_expression_value()) { + dynamic_sampler_array_indexing = true; + return visit_stop; + } + return visit_continue; + } + + bool uses_dynamic_sampler_array_indexing() + { + return dynamic_sampler_array_indexing; + } + +private: + bool dynamic_sampler_array_indexing; +}; + +} /* anonymous namespace */ + +void +linker_error(gl_shader_program *prog, const char *fmt, ...) +{ + va_list ap; + + ralloc_strcat(&prog->InfoLog, "error: "); + va_start(ap, fmt); + ralloc_vasprintf_append(&prog->InfoLog, fmt, ap); + va_end(ap); + + prog->LinkStatus = false; +} + + +void +linker_warning(gl_shader_program *prog, const char *fmt, ...) +{ + va_list ap; + + ralloc_strcat(&prog->InfoLog, "warning: "); + va_start(ap, fmt); + ralloc_vasprintf_append(&prog->InfoLog, fmt, ap); + va_end(ap); + +} + + +/** + * Given a string identifying a program resource, break it into a base name + * and an optional array index in square brackets. + * + * If an array index is present, \c out_base_name_end is set to point to the + * "[" that precedes the array index, and the array index itself is returned + * as a long. + * + * If no array index is present (or if the array index is negative or + * mal-formed), \c out_base_name_end, is set to point to the null terminator + * at the end of the input string, and -1 is returned. + * + * Only the final array index is parsed; if the string contains other array + * indices (or structure field accesses), they are left in the base name. + * + * No attempt is made to check that the base name is properly formed; + * typically the caller will look up the base name in a hash table, so + * ill-formed base names simply turn into hash table lookup failures. + */ +long +parse_program_resource_name(const GLchar *name, + const GLchar **out_base_name_end) +{ + /* Section 7.3.1 ("Program Interfaces") of the OpenGL 4.3 spec says: + * + * "When an integer array element or block instance number is part of + * the name string, it will be specified in decimal form without a "+" + * or "-" sign or any extra leading zeroes. Additionally, the name + * string will not include white space anywhere in the string." + */ + + const size_t len = strlen(name); + *out_base_name_end = name + len; + + if (len == 0 || name[len-1] != ']') + return -1; + + /* Walk backwards over the string looking for a non-digit character. This + * had better be the opening bracket for an array index. + * + * Initially, i specifies the location of the ']'. Since the string may + * contain only the ']' charcater, walk backwards very carefully. + */ + unsigned i; + for (i = len - 1; (i > 0) && isdigit(name[i-1]); --i) + /* empty */ ; + + if ((i == 0) || name[i-1] != '[') + return -1; + + long array_index = strtol(&name[i], NULL, 10); + if (array_index < 0) + return -1; + + /* Check for leading zero */ + if (name[i] == '0' && name[i+1] != ']') + return -1; + + *out_base_name_end = name + (i - 1); + return array_index; +} + + +void +link_invalidate_variable_locations(exec_list *ir) +{ + foreach_in_list(ir_instruction, node, ir) { + ir_variable *const var = node->as_variable(); + + if (var == NULL) + continue; + + /* Only assign locations for variables that lack an explicit location. + * Explicit locations are set for all built-in variables, generic vertex + * shader inputs (via layout(location=...)), and generic fragment shader + * outputs (also via layout(location=...)). + */ + if (!var->data.explicit_location) { + var->data.location = -1; + var->data.location_frac = 0; + } + + /* ir_variable::is_unmatched_generic_inout is used by the linker while + * connecting outputs from one stage to inputs of the next stage. + */ + if (var->data.explicit_location && + var->data.location < VARYING_SLOT_VAR0) { + var->data.is_unmatched_generic_inout = 0; + } else { + var->data.is_unmatched_generic_inout = 1; + } + } +} + + +/** + * Set clip_distance_array_size based on the given shader. + * + * Also check for errors based on incorrect usage of gl_ClipVertex and + * gl_ClipDistance. + * + * Return false if an error was reported. + */ +static void +analyze_clip_usage(struct gl_shader_program *prog, + struct gl_shader *shader, + GLuint *clip_distance_array_size) +{ + *clip_distance_array_size = 0; + + if (!prog->IsES && prog->Version >= 130) { + /* From section 7.1 (Vertex Shader Special Variables) of the + * GLSL 1.30 spec: + * + * "It is an error for a shader to statically write both + * gl_ClipVertex and gl_ClipDistance." + * + * This does not apply to GLSL ES shaders, since GLSL ES defines neither + * gl_ClipVertex nor gl_ClipDistance. + */ + find_assignment_visitor clip_vertex("gl_ClipVertex"); + find_assignment_visitor clip_distance("gl_ClipDistance"); + + clip_vertex.run(shader->ir); + clip_distance.run(shader->ir); + if (clip_vertex.variable_found() && clip_distance.variable_found()) { + linker_error(prog, "%s shader writes to both `gl_ClipVertex' " + "and `gl_ClipDistance'\n", + _mesa_shader_stage_to_string(shader->Stage)); + return; + } + + if (clip_distance.variable_found()) { + ir_variable *clip_distance_var = + shader->symbols->get_variable("gl_ClipDistance"); + + assert(clip_distance_var); + *clip_distance_array_size = clip_distance_var->type->length; + } + } +} + + +/** + * Verify that a vertex shader executable meets all semantic requirements. + * + * Also sets prog->Vert.ClipDistanceArraySize as a side effect. + * + * \param shader Vertex shader executable to be verified + */ +void +validate_vertex_shader_executable(struct gl_shader_program *prog, + struct gl_shader *shader) +{ + if (shader == NULL) + return; + + /* From the GLSL 1.10 spec, page 48: + * + * "The variable gl_Position is available only in the vertex + * language and is intended for writing the homogeneous vertex + * position. All executions of a well-formed vertex shader + * executable must write a value into this variable. [...] The + * variable gl_Position is available only in the vertex + * language and is intended for writing the homogeneous vertex + * position. All executions of a well-formed vertex shader + * executable must write a value into this variable." + * + * while in GLSL 1.40 this text is changed to: + * + * "The variable gl_Position is available only in the vertex + * language and is intended for writing the homogeneous vertex + * position. It can be written at any time during shader + * execution. It may also be read back by a vertex shader + * after being written. This value will be used by primitive + * assembly, clipping, culling, and other fixed functionality + * operations, if present, that operate on primitives after + * vertex processing has occurred. Its value is undefined if + * the vertex shader executable does not write gl_Position." + * + * All GLSL ES Versions are similar to GLSL 1.40--failing to write to + * gl_Position is not an error. + */ + if (prog->Version < (prog->IsES ? 300 : 140)) { + find_assignment_visitor find("gl_Position"); + find.run(shader->ir); + if (!find.variable_found()) { + if (prog->IsES) { + linker_warning(prog, + "vertex shader does not write to `gl_Position'." + "It's value is undefined. \n"); + } else { + linker_error(prog, + "vertex shader does not write to `gl_Position'. \n"); + } + return; + } + } + + analyze_clip_usage(prog, shader, &prog->Vert.ClipDistanceArraySize); +} + +void +validate_tess_eval_shader_executable(struct gl_shader_program *prog, + struct gl_shader *shader) +{ + if (shader == NULL) + return; + + analyze_clip_usage(prog, shader, &prog->TessEval.ClipDistanceArraySize); +} + + +/** + * Verify that a fragment shader executable meets all semantic requirements + * + * \param shader Fragment shader executable to be verified + */ +void +validate_fragment_shader_executable(struct gl_shader_program *prog, + struct gl_shader *shader) +{ + if (shader == NULL) + return; + + find_assignment_visitor frag_color("gl_FragColor"); + find_assignment_visitor frag_data("gl_FragData"); + + frag_color.run(shader->ir); + frag_data.run(shader->ir); + + if (frag_color.variable_found() && frag_data.variable_found()) { + linker_error(prog, "fragment shader writes to both " + "`gl_FragColor' and `gl_FragData'\n"); + } +} + +/** + * Verify that a geometry shader executable meets all semantic requirements + * + * Also sets prog->Geom.VerticesIn, and prog->Geom.ClipDistanceArraySize as + * a side effect. + * + * \param shader Geometry shader executable to be verified + */ +void +validate_geometry_shader_executable(struct gl_shader_program *prog, + struct gl_shader *shader) +{ + if (shader == NULL) + return; + + unsigned num_vertices = vertices_per_prim(prog->Geom.InputType); + prog->Geom.VerticesIn = num_vertices; + + analyze_clip_usage(prog, shader, &prog->Geom.ClipDistanceArraySize); +} + +/** + * Check if geometry shaders emit to non-zero streams and do corresponding + * validations. + */ +static void +validate_geometry_shader_emissions(struct gl_context *ctx, + struct gl_shader_program *prog) +{ + if (prog->_LinkedShaders[MESA_SHADER_GEOMETRY] != NULL) { + find_emit_vertex_visitor emit_vertex(ctx->Const.MaxVertexStreams - 1); + emit_vertex.run(prog->_LinkedShaders[MESA_SHADER_GEOMETRY]->ir); + if (emit_vertex.error()) { + linker_error(prog, "Invalid call %s(%d). Accepted values for the " + "stream parameter are in the range [0, %d].\n", + emit_vertex.error_func(), + emit_vertex.error_stream(), + ctx->Const.MaxVertexStreams - 1); + } + prog->Geom.UsesStreams = emit_vertex.uses_streams(); + prog->Geom.UsesEndPrimitive = emit_vertex.uses_end_primitive(); + + /* From the ARB_gpu_shader5 spec: + * + * "Multiple vertex streams are supported only if the output primitive + * type is declared to be "points". A program will fail to link if it + * contains a geometry shader calling EmitStreamVertex() or + * EndStreamPrimitive() if its output primitive type is not "points". + * + * However, in the same spec: + * + * "The function EmitVertex() is equivalent to calling EmitStreamVertex() + * with <stream> set to zero." + * + * And: + * + * "The function EndPrimitive() is equivalent to calling + * EndStreamPrimitive() with <stream> set to zero." + * + * Since we can call EmitVertex() and EndPrimitive() when we output + * primitives other than points, calling EmitStreamVertex(0) or + * EmitEndPrimitive(0) should not produce errors. This it also what Nvidia + * does. Currently we only set prog->Geom.UsesStreams to TRUE when + * EmitStreamVertex() or EmitEndPrimitive() are called with a non-zero + * stream. + */ + if (prog->Geom.UsesStreams && prog->Geom.OutputType != GL_POINTS) { + linker_error(prog, "EmitStreamVertex(n) and EndStreamPrimitive(n) " + "with n>0 requires point output\n"); + } + } +} + +bool +validate_intrastage_arrays(struct gl_shader_program *prog, + ir_variable *const var, + ir_variable *const existing) +{ + /* Consider the types to be "the same" if both types are arrays + * of the same type and one of the arrays is implicitly sized. + * In addition, set the type of the linked variable to the + * explicitly sized array. + */ + if (var->type->is_array() && existing->type->is_array()) { + if ((var->type->fields.array == existing->type->fields.array) && + ((var->type->length == 0)|| (existing->type->length == 0))) { + if (var->type->length != 0) { + if (var->type->length <= existing->data.max_array_access) { + linker_error(prog, "%s `%s' declared as type " + "`%s' but outermost dimension has an index" + " of `%i'\n", + mode_string(var), + var->name, var->type->name, + existing->data.max_array_access); + } + existing->type = var->type; + return true; + } else if (existing->type->length != 0) { + if(existing->type->length <= var->data.max_array_access && + !existing->data.from_ssbo_unsized_array) { + linker_error(prog, "%s `%s' declared as type " + "`%s' but outermost dimension has an index" + " of `%i'\n", + mode_string(var), + var->name, existing->type->name, + var->data.max_array_access); + } + return true; + } + } else { + /* The arrays of structs could have different glsl_type pointers but + * they are actually the same type. Use record_compare() to check that. + */ + if (existing->type->fields.array->is_record() && + var->type->fields.array->is_record() && + existing->type->fields.array->record_compare(var->type->fields.array)) + return true; + } + } + return false; +} + + +/** + * Perform validation of global variables used across multiple shaders + */ +void +cross_validate_globals(struct gl_shader_program *prog, + struct gl_shader **shader_list, + unsigned num_shaders, + bool uniforms_only) +{ + /* Examine all of the uniforms in all of the shaders and cross validate + * them. + */ + glsl_symbol_table variables; + for (unsigned i = 0; i < num_shaders; i++) { + if (shader_list[i] == NULL) + continue; + + foreach_in_list(ir_instruction, node, shader_list[i]->ir) { + ir_variable *const var = node->as_variable(); + + if (var == NULL) + continue; + + if (uniforms_only && (var->data.mode != ir_var_uniform && var->data.mode != ir_var_shader_storage)) + continue; + + /* don't cross validate subroutine uniforms */ + if (var->type->contains_subroutine()) + continue; + + /* Don't cross validate temporaries that are at global scope. These + * will eventually get pulled into the shaders 'main'. + */ + if (var->data.mode == ir_var_temporary) + continue; + + /* If a global with this name has already been seen, verify that the + * new instance has the same type. In addition, if the globals have + * initializers, the values of the initializers must be the same. + */ + ir_variable *const existing = variables.get_variable(var->name); + if (existing != NULL) { + /* Check if types match. Interface blocks have some special + * rules so we handle those elsewhere. + */ + if (var->type != existing->type && + !var->is_interface_instance()) { + if (!validate_intrastage_arrays(prog, var, existing)) { + if (var->type->is_record() && existing->type->is_record() + && existing->type->record_compare(var->type)) { + existing->type = var->type; + } else { + /* If it is an unsized array in a Shader Storage Block, + * two different shaders can access to different elements. + * Because of that, they might be converted to different + * sized arrays, then check that they are compatible but + * ignore the array size. + */ + if (!(var->data.mode == ir_var_shader_storage && + var->data.from_ssbo_unsized_array && + existing->data.mode == ir_var_shader_storage && + existing->data.from_ssbo_unsized_array && + var->type->gl_type == existing->type->gl_type)) { + linker_error(prog, "%s `%s' declared as type " + "`%s' and type `%s'\n", + mode_string(var), + var->name, var->type->name, + existing->type->name); + return; + } + } + } + } + + if (var->data.explicit_location) { + if (existing->data.explicit_location + && (var->data.location != existing->data.location)) { + linker_error(prog, "explicit locations for %s " + "`%s' have differing values\n", + mode_string(var), var->name); + return; + } + + existing->data.location = var->data.location; + existing->data.explicit_location = true; + } else { + /* Check if uniform with implicit location was marked explicit + * by earlier shader stage. If so, mark it explicit in this stage + * too to make sure later processing does not treat it as + * implicit one. + */ + if (existing->data.explicit_location) { + var->data.location = existing->data.location; + var->data.explicit_location = true; + } + } + + /* From the GLSL 4.20 specification: + * "A link error will result if two compilation units in a program + * specify different integer-constant bindings for the same + * opaque-uniform name. However, it is not an error to specify a + * binding on some but not all declarations for the same name" + */ + if (var->data.explicit_binding) { + if (existing->data.explicit_binding && + var->data.binding != existing->data.binding) { + linker_error(prog, "explicit bindings for %s " + "`%s' have differing values\n", + mode_string(var), var->name); + return; + } + + existing->data.binding = var->data.binding; + existing->data.explicit_binding = true; + } + + if (var->type->contains_atomic() && + var->data.offset != existing->data.offset) { + linker_error(prog, "offset specifications for %s " + "`%s' have differing values\n", + mode_string(var), var->name); + return; + } + + /* Validate layout qualifiers for gl_FragDepth. + * + * From the AMD/ARB_conservative_depth specs: + * + * "If gl_FragDepth is redeclared in any fragment shader in a + * program, it must be redeclared in all fragment shaders in + * that program that have static assignments to + * gl_FragDepth. All redeclarations of gl_FragDepth in all + * fragment shaders in a single program must have the same set + * of qualifiers." + */ + if (strcmp(var->name, "gl_FragDepth") == 0) { + bool layout_declared = var->data.depth_layout != ir_depth_layout_none; + bool layout_differs = + var->data.depth_layout != existing->data.depth_layout; + + if (layout_declared && layout_differs) { + linker_error(prog, + "All redeclarations of gl_FragDepth in all " + "fragment shaders in a single program must have " + "the same set of qualifiers.\n"); + } + + if (var->data.used && layout_differs) { + linker_error(prog, + "If gl_FragDepth is redeclared with a layout " + "qualifier in any fragment shader, it must be " + "redeclared with the same layout qualifier in " + "all fragment shaders that have assignments to " + "gl_FragDepth\n"); + } + } + + /* Page 35 (page 41 of the PDF) of the GLSL 4.20 spec says: + * + * "If a shared global has multiple initializers, the + * initializers must all be constant expressions, and they + * must all have the same value. Otherwise, a link error will + * result. (A shared global having only one initializer does + * not require that initializer to be a constant expression.)" + * + * Previous to 4.20 the GLSL spec simply said that initializers + * must have the same value. In this case of non-constant + * initializers, this was impossible to determine. As a result, + * no vendor actually implemented that behavior. The 4.20 + * behavior matches the implemented behavior of at least one other + * vendor, so we'll implement that for all GLSL versions. + */ + if (var->constant_initializer != NULL) { + if (existing->constant_initializer != NULL) { + if (!var->constant_initializer->has_value(existing->constant_initializer)) { + linker_error(prog, "initializers for %s " + "`%s' have differing values\n", + mode_string(var), var->name); + return; + } + } else { + /* If the first-seen instance of a particular uniform did not + * have an initializer but a later instance does, copy the + * initializer to the version stored in the symbol table. + */ + /* FINISHME: This is wrong. The constant_value field should + * FINISHME: not be modified! Imagine a case where a shader + * FINISHME: without an initializer is linked in two different + * FINISHME: programs with shaders that have differing + * FINISHME: initializers. Linking with the first will + * FINISHME: modify the shader, and linking with the second + * FINISHME: will fail. + */ + existing->constant_initializer = + var->constant_initializer->clone(ralloc_parent(existing), + NULL); + } + } + + if (var->data.has_initializer) { + if (existing->data.has_initializer + && (var->constant_initializer == NULL + || existing->constant_initializer == NULL)) { + linker_error(prog, + "shared global variable `%s' has multiple " + "non-constant initializers.\n", + var->name); + return; + } + + /* Some instance had an initializer, so keep track of that. In + * this location, all sorts of initializers (constant or + * otherwise) will propagate the existence to the variable + * stored in the symbol table. + */ + existing->data.has_initializer = true; + } + + if (existing->data.invariant != var->data.invariant) { + linker_error(prog, "declarations for %s `%s' have " + "mismatching invariant qualifiers\n", + mode_string(var), var->name); + return; + } + if (existing->data.centroid != var->data.centroid) { + linker_error(prog, "declarations for %s `%s' have " + "mismatching centroid qualifiers\n", + mode_string(var), var->name); + return; + } + if (existing->data.sample != var->data.sample) { + linker_error(prog, "declarations for %s `%s` have " + "mismatching sample qualifiers\n", + mode_string(var), var->name); + return; + } + if (existing->data.image_format != var->data.image_format) { + linker_error(prog, "declarations for %s `%s` have " + "mismatching image format qualifiers\n", + mode_string(var), var->name); + return; + } + } else + variables.add_variable(var); + } + } +} + + +/** + * Perform validation of uniforms used across multiple shader stages + */ +void +cross_validate_uniforms(struct gl_shader_program *prog) +{ + cross_validate_globals(prog, prog->_LinkedShaders, + MESA_SHADER_STAGES, true); +} + +/** + * Accumulates the array of prog->BufferInterfaceBlocks and checks that all + * definitons of blocks agree on their contents. + */ +static bool +interstage_cross_validate_uniform_blocks(struct gl_shader_program *prog) +{ + unsigned max_num_uniform_blocks = 0; + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i]) + max_num_uniform_blocks += prog->_LinkedShaders[i]->NumBufferInterfaceBlocks; + } + + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + + prog->InterfaceBlockStageIndex[i] = ralloc_array(prog, int, + max_num_uniform_blocks); + for (unsigned int j = 0; j < max_num_uniform_blocks; j++) + prog->InterfaceBlockStageIndex[i][j] = -1; + + if (sh == NULL) + continue; + + for (unsigned int j = 0; j < sh->NumBufferInterfaceBlocks; j++) { + int index = link_cross_validate_uniform_block(prog, + &prog->BufferInterfaceBlocks, + &prog->NumBufferInterfaceBlocks, + &sh->BufferInterfaceBlocks[j]); + + if (index == -1) { + linker_error(prog, "uniform block `%s' has mismatching definitions\n", + sh->BufferInterfaceBlocks[j].Name); + return false; + } + + prog->InterfaceBlockStageIndex[i][index] = j; + } + } + + return true; +} + + +/** + * Populates a shaders symbol table with all global declarations + */ +static void +populate_symbol_table(gl_shader *sh) +{ + sh->symbols = new(sh) glsl_symbol_table; + + foreach_in_list(ir_instruction, inst, sh->ir) { + ir_variable *var; + ir_function *func; + + if ((func = inst->as_function()) != NULL) { + sh->symbols->add_function(func); + } else if ((var = inst->as_variable()) != NULL) { + if (var->data.mode != ir_var_temporary) + sh->symbols->add_variable(var); + } + } +} + + +/** + * Remap variables referenced in an instruction tree + * + * This is used when instruction trees are cloned from one shader and placed in + * another. These trees will contain references to \c ir_variable nodes that + * do not exist in the target shader. This function finds these \c ir_variable + * references and replaces the references with matching variables in the target + * shader. + * + * If there is no matching variable in the target shader, a clone of the + * \c ir_variable is made and added to the target shader. The new variable is + * added to \b both the instruction stream and the symbol table. + * + * \param inst IR tree that is to be processed. + * \param symbols Symbol table containing global scope symbols in the + * linked shader. + * \param instructions Instruction stream where new variable declarations + * should be added. + */ +void +remap_variables(ir_instruction *inst, struct gl_shader *target, + hash_table *temps) +{ + class remap_visitor : public ir_hierarchical_visitor { + public: + remap_visitor(struct gl_shader *target, + hash_table *temps) + { + this->target = target; + this->symbols = target->symbols; + this->instructions = target->ir; + this->temps = temps; + } + + virtual ir_visitor_status visit(ir_dereference_variable *ir) + { + if (ir->var->data.mode == ir_var_temporary) { + ir_variable *var = (ir_variable *) hash_table_find(temps, ir->var); + + assert(var != NULL); + ir->var = var; + return visit_continue; + } + + ir_variable *const existing = + this->symbols->get_variable(ir->var->name); + if (existing != NULL) + ir->var = existing; + else { + ir_variable *copy = ir->var->clone(this->target, NULL); + + this->symbols->add_variable(copy); + this->instructions->push_head(copy); + ir->var = copy; + } + + return visit_continue; + } + + private: + struct gl_shader *target; + glsl_symbol_table *symbols; + exec_list *instructions; + hash_table *temps; + }; + + remap_visitor v(target, temps); + + inst->accept(&v); +} + + +/** + * Move non-declarations from one instruction stream to another + * + * The intended usage pattern of this function is to pass the pointer to the + * head sentinel of a list (i.e., a pointer to the list cast to an \c exec_node + * pointer) for \c last and \c false for \c make_copies on the first + * call. Successive calls pass the return value of the previous call for + * \c last and \c true for \c make_copies. + * + * \param instructions Source instruction stream + * \param last Instruction after which new instructions should be + * inserted in the target instruction stream + * \param make_copies Flag selecting whether instructions in \c instructions + * should be copied (via \c ir_instruction::clone) into the + * target list or moved. + * + * \return + * The new "last" instruction in the target instruction stream. This pointer + * is suitable for use as the \c last parameter of a later call to this + * function. + */ +exec_node * +move_non_declarations(exec_list *instructions, exec_node *last, + bool make_copies, gl_shader *target) +{ + hash_table *temps = NULL; + + if (make_copies) + temps = hash_table_ctor(0, hash_table_pointer_hash, + hash_table_pointer_compare); + + foreach_in_list_safe(ir_instruction, inst, instructions) { + if (inst->as_function()) + continue; + + ir_variable *var = inst->as_variable(); + if ((var != NULL) && (var->data.mode != ir_var_temporary)) + continue; + + assert(inst->as_assignment() + || inst->as_call() + || inst->as_if() /* for initializers with the ?: operator */ + || ((var != NULL) && (var->data.mode == ir_var_temporary))); + + if (make_copies) { + inst = inst->clone(target, NULL); + + if (var != NULL) + hash_table_insert(temps, inst, var); + else + remap_variables(inst, target, temps); + } else { + inst->remove(); + } + + last->insert_after(inst); + last = inst; + } + + if (make_copies) + hash_table_dtor(temps); + + return last; +} + + +/** + * This class is only used in link_intrastage_shaders() below but declaring + * it inside that function leads to compiler warnings with some versions of + * gcc. + */ +class array_sizing_visitor : public ir_hierarchical_visitor { +public: + array_sizing_visitor() + : mem_ctx(ralloc_context(NULL)), + unnamed_interfaces(hash_table_ctor(0, hash_table_pointer_hash, + hash_table_pointer_compare)) + { + } + + ~array_sizing_visitor() + { + hash_table_dtor(this->unnamed_interfaces); + ralloc_free(this->mem_ctx); + } + + virtual ir_visitor_status visit(ir_variable *var) + { + const glsl_type *type_without_array; + fixup_type(&var->type, var->data.max_array_access, + var->data.from_ssbo_unsized_array); + type_without_array = var->type->without_array(); + if (var->type->is_interface()) { + if (interface_contains_unsized_arrays(var->type)) { + const glsl_type *new_type = + resize_interface_members(var->type, + var->get_max_ifc_array_access(), + var->is_in_shader_storage_block()); + var->type = new_type; + var->change_interface_type(new_type); + } + } else if (type_without_array->is_interface()) { + if (interface_contains_unsized_arrays(type_without_array)) { + const glsl_type *new_type = + resize_interface_members(type_without_array, + var->get_max_ifc_array_access(), + var->is_in_shader_storage_block()); + var->change_interface_type(new_type); + var->type = update_interface_members_array(var->type, new_type); + } + } else if (const glsl_type *ifc_type = var->get_interface_type()) { + /* Store a pointer to the variable in the unnamed_interfaces + * hashtable. + */ + ir_variable **interface_vars = (ir_variable **) + hash_table_find(this->unnamed_interfaces, ifc_type); + if (interface_vars == NULL) { + interface_vars = rzalloc_array(mem_ctx, ir_variable *, + ifc_type->length); + hash_table_insert(this->unnamed_interfaces, interface_vars, + ifc_type); + } + unsigned index = ifc_type->field_index(var->name); + assert(index < ifc_type->length); + assert(interface_vars[index] == NULL); + interface_vars[index] = var; + } + return visit_continue; + } + + /** + * For each unnamed interface block that was discovered while running the + * visitor, adjust the interface type to reflect the newly assigned array + * sizes, and fix up the ir_variable nodes to point to the new interface + * type. + */ + void fixup_unnamed_interface_types() + { + hash_table_call_foreach(this->unnamed_interfaces, + fixup_unnamed_interface_type, NULL); + } + +private: + /** + * If the type pointed to by \c type represents an unsized array, replace + * it with a sized array whose size is determined by max_array_access. + */ + static void fixup_type(const glsl_type **type, unsigned max_array_access, + bool from_ssbo_unsized_array) + { + if (!from_ssbo_unsized_array && (*type)->is_unsized_array()) { + *type = glsl_type::get_array_instance((*type)->fields.array, + max_array_access + 1); + assert(*type != NULL); + } + } + + static const glsl_type * + update_interface_members_array(const glsl_type *type, + const glsl_type *new_interface_type) + { + const glsl_type *element_type = type->fields.array; + if (element_type->is_array()) { + const glsl_type *new_array_type = + update_interface_members_array(element_type, new_interface_type); + return glsl_type::get_array_instance(new_array_type, type->length); + } else { + return glsl_type::get_array_instance(new_interface_type, + type->length); + } + } + + /** + * Determine whether the given interface type contains unsized arrays (if + * it doesn't, array_sizing_visitor doesn't need to process it). + */ + static bool interface_contains_unsized_arrays(const glsl_type *type) + { + for (unsigned i = 0; i < type->length; i++) { + const glsl_type *elem_type = type->fields.structure[i].type; + if (elem_type->is_unsized_array()) + return true; + } + return false; + } + + /** + * Create a new interface type based on the given type, with unsized arrays + * replaced by sized arrays whose size is determined by + * max_ifc_array_access. + */ + static const glsl_type * + resize_interface_members(const glsl_type *type, + const unsigned *max_ifc_array_access, + bool is_ssbo) + { + unsigned num_fields = type->length; + glsl_struct_field *fields = new glsl_struct_field[num_fields]; + memcpy(fields, type->fields.structure, + num_fields * sizeof(*fields)); + for (unsigned i = 0; i < num_fields; i++) { + /* If SSBO last member is unsized array, we don't replace it by a sized + * array. + */ + if (is_ssbo && i == (num_fields - 1)) + fixup_type(&fields[i].type, max_ifc_array_access[i], + true); + else + fixup_type(&fields[i].type, max_ifc_array_access[i], + false); + } + glsl_interface_packing packing = + (glsl_interface_packing) type->interface_packing; + const glsl_type *new_ifc_type = + glsl_type::get_interface_instance(fields, num_fields, + packing, type->name); + delete [] fields; + return new_ifc_type; + } + + static void fixup_unnamed_interface_type(const void *key, void *data, + void *) + { + const glsl_type *ifc_type = (const glsl_type *) key; + ir_variable **interface_vars = (ir_variable **) data; + unsigned num_fields = ifc_type->length; + glsl_struct_field *fields = new glsl_struct_field[num_fields]; + memcpy(fields, ifc_type->fields.structure, + num_fields * sizeof(*fields)); + bool interface_type_changed = false; + for (unsigned i = 0; i < num_fields; i++) { + if (interface_vars[i] != NULL && + fields[i].type != interface_vars[i]->type) { + fields[i].type = interface_vars[i]->type; + interface_type_changed = true; + } + } + if (!interface_type_changed) { + delete [] fields; + return; + } + glsl_interface_packing packing = + (glsl_interface_packing) ifc_type->interface_packing; + const glsl_type *new_ifc_type = + glsl_type::get_interface_instance(fields, num_fields, packing, + ifc_type->name); + delete [] fields; + for (unsigned i = 0; i < num_fields; i++) { + if (interface_vars[i] != NULL) + interface_vars[i]->change_interface_type(new_ifc_type); + } + } + + /** + * Memory context used to allocate the data in \c unnamed_interfaces. + */ + void *mem_ctx; + + /** + * Hash table from const glsl_type * to an array of ir_variable *'s + * pointing to the ir_variables constituting each unnamed interface block. + */ + hash_table *unnamed_interfaces; +}; + + +/** + * Performs the cross-validation of tessellation control shader vertices and + * layout qualifiers for the attached tessellation control shaders, + * and propagates them to the linked TCS and linked shader program. + */ +static void +link_tcs_out_layout_qualifiers(struct gl_shader_program *prog, + struct gl_shader *linked_shader, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + linked_shader->TessCtrl.VerticesOut = 0; + + if (linked_shader->Stage != MESA_SHADER_TESS_CTRL) + return; + + /* From the GLSL 4.0 spec (chapter 4.3.8.2): + * + * "All tessellation control shader layout declarations in a program + * must specify the same output patch vertex count. There must be at + * least one layout qualifier specifying an output patch vertex count + * in any program containing tessellation control shaders; however, + * such a declaration is not required in all tessellation control + * shaders." + */ + + for (unsigned i = 0; i < num_shaders; i++) { + struct gl_shader *shader = shader_list[i]; + + if (shader->TessCtrl.VerticesOut != 0) { + if (linked_shader->TessCtrl.VerticesOut != 0 && + linked_shader->TessCtrl.VerticesOut != shader->TessCtrl.VerticesOut) { + linker_error(prog, "tessellation control shader defined with " + "conflicting output vertex count (%d and %d)\n", + linked_shader->TessCtrl.VerticesOut, + shader->TessCtrl.VerticesOut); + return; + } + linked_shader->TessCtrl.VerticesOut = shader->TessCtrl.VerticesOut; + } + } + + /* Just do the intrastage -> interstage propagation right now, + * since we already know we're in the right type of shader program + * for doing it. + */ + if (linked_shader->TessCtrl.VerticesOut == 0) { + linker_error(prog, "tessellation control shader didn't declare " + "vertices out layout qualifier\n"); + return; + } + prog->TessCtrl.VerticesOut = linked_shader->TessCtrl.VerticesOut; +} + + +/** + * Performs the cross-validation of tessellation evaluation shader + * primitive type, vertex spacing, ordering and point_mode layout qualifiers + * for the attached tessellation evaluation shaders, and propagates them + * to the linked TES and linked shader program. + */ +static void +link_tes_in_layout_qualifiers(struct gl_shader_program *prog, + struct gl_shader *linked_shader, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + linked_shader->TessEval.PrimitiveMode = PRIM_UNKNOWN; + linked_shader->TessEval.Spacing = 0; + linked_shader->TessEval.VertexOrder = 0; + linked_shader->TessEval.PointMode = -1; + + if (linked_shader->Stage != MESA_SHADER_TESS_EVAL) + return; + + /* From the GLSL 4.0 spec (chapter 4.3.8.1): + * + * "At least one tessellation evaluation shader (compilation unit) in + * a program must declare a primitive mode in its input layout. + * Declaration vertex spacing, ordering, and point mode identifiers is + * optional. It is not required that all tessellation evaluation + * shaders in a program declare a primitive mode. If spacing or + * vertex ordering declarations are omitted, the tessellation + * primitive generator will use equal spacing or counter-clockwise + * vertex ordering, respectively. If a point mode declaration is + * omitted, the tessellation primitive generator will produce lines or + * triangles according to the primitive mode." + */ + + for (unsigned i = 0; i < num_shaders; i++) { + struct gl_shader *shader = shader_list[i]; + + if (shader->TessEval.PrimitiveMode != PRIM_UNKNOWN) { + if (linked_shader->TessEval.PrimitiveMode != PRIM_UNKNOWN && + linked_shader->TessEval.PrimitiveMode != shader->TessEval.PrimitiveMode) { + linker_error(prog, "tessellation evaluation shader defined with " + "conflicting input primitive modes.\n"); + return; + } + linked_shader->TessEval.PrimitiveMode = shader->TessEval.PrimitiveMode; + } + + if (shader->TessEval.Spacing != 0) { + if (linked_shader->TessEval.Spacing != 0 && + linked_shader->TessEval.Spacing != shader->TessEval.Spacing) { + linker_error(prog, "tessellation evaluation shader defined with " + "conflicting vertex spacing.\n"); + return; + } + linked_shader->TessEval.Spacing = shader->TessEval.Spacing; + } + + if (shader->TessEval.VertexOrder != 0) { + if (linked_shader->TessEval.VertexOrder != 0 && + linked_shader->TessEval.VertexOrder != shader->TessEval.VertexOrder) { + linker_error(prog, "tessellation evaluation shader defined with " + "conflicting ordering.\n"); + return; + } + linked_shader->TessEval.VertexOrder = shader->TessEval.VertexOrder; + } + + if (shader->TessEval.PointMode != -1) { + if (linked_shader->TessEval.PointMode != -1 && + linked_shader->TessEval.PointMode != shader->TessEval.PointMode) { + linker_error(prog, "tessellation evaluation shader defined with " + "conflicting point modes.\n"); + return; + } + linked_shader->TessEval.PointMode = shader->TessEval.PointMode; + } + + } + + /* Just do the intrastage -> interstage propagation right now, + * since we already know we're in the right type of shader program + * for doing it. + */ + if (linked_shader->TessEval.PrimitiveMode == PRIM_UNKNOWN) { + linker_error(prog, + "tessellation evaluation shader didn't declare input " + "primitive modes.\n"); + return; + } + prog->TessEval.PrimitiveMode = linked_shader->TessEval.PrimitiveMode; + + if (linked_shader->TessEval.Spacing == 0) + linked_shader->TessEval.Spacing = GL_EQUAL; + prog->TessEval.Spacing = linked_shader->TessEval.Spacing; + + if (linked_shader->TessEval.VertexOrder == 0) + linked_shader->TessEval.VertexOrder = GL_CCW; + prog->TessEval.VertexOrder = linked_shader->TessEval.VertexOrder; + + if (linked_shader->TessEval.PointMode == -1) + linked_shader->TessEval.PointMode = GL_FALSE; + prog->TessEval.PointMode = linked_shader->TessEval.PointMode; +} + + +/** + * Performs the cross-validation of layout qualifiers specified in + * redeclaration of gl_FragCoord for the attached fragment shaders, + * and propagates them to the linked FS and linked shader program. + */ +static void +link_fs_input_layout_qualifiers(struct gl_shader_program *prog, + struct gl_shader *linked_shader, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + linked_shader->redeclares_gl_fragcoord = false; + linked_shader->uses_gl_fragcoord = false; + linked_shader->origin_upper_left = false; + linked_shader->pixel_center_integer = false; + + if (linked_shader->Stage != MESA_SHADER_FRAGMENT || + (prog->Version < 150 && !prog->ARB_fragment_coord_conventions_enable)) + return; + + for (unsigned i = 0; i < num_shaders; i++) { + struct gl_shader *shader = shader_list[i]; + /* From the GLSL 1.50 spec, page 39: + * + * "If gl_FragCoord is redeclared in any fragment shader in a program, + * it must be redeclared in all the fragment shaders in that program + * that have a static use gl_FragCoord." + */ + if ((linked_shader->redeclares_gl_fragcoord + && !shader->redeclares_gl_fragcoord + && shader->uses_gl_fragcoord) + || (shader->redeclares_gl_fragcoord + && !linked_shader->redeclares_gl_fragcoord + && linked_shader->uses_gl_fragcoord)) { + linker_error(prog, "fragment shader defined with conflicting " + "layout qualifiers for gl_FragCoord\n"); + } + + /* From the GLSL 1.50 spec, page 39: + * + * "All redeclarations of gl_FragCoord in all fragment shaders in a + * single program must have the same set of qualifiers." + */ + if (linked_shader->redeclares_gl_fragcoord && shader->redeclares_gl_fragcoord + && (shader->origin_upper_left != linked_shader->origin_upper_left + || shader->pixel_center_integer != linked_shader->pixel_center_integer)) { + linker_error(prog, "fragment shader defined with conflicting " + "layout qualifiers for gl_FragCoord\n"); + } + + /* Update the linked shader state. Note that uses_gl_fragcoord should + * accumulate the results. The other values should replace. If there + * are multiple redeclarations, all the fields except uses_gl_fragcoord + * are already known to be the same. + */ + if (shader->redeclares_gl_fragcoord || shader->uses_gl_fragcoord) { + linked_shader->redeclares_gl_fragcoord = + shader->redeclares_gl_fragcoord; + linked_shader->uses_gl_fragcoord = linked_shader->uses_gl_fragcoord + || shader->uses_gl_fragcoord; + linked_shader->origin_upper_left = shader->origin_upper_left; + linked_shader->pixel_center_integer = shader->pixel_center_integer; + } + + linked_shader->EarlyFragmentTests |= shader->EarlyFragmentTests; + } +} + +/** + * Performs the cross-validation of geometry shader max_vertices and + * primitive type layout qualifiers for the attached geometry shaders, + * and propagates them to the linked GS and linked shader program. + */ +static void +link_gs_inout_layout_qualifiers(struct gl_shader_program *prog, + struct gl_shader *linked_shader, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + linked_shader->Geom.VerticesOut = 0; + linked_shader->Geom.Invocations = 0; + linked_shader->Geom.InputType = PRIM_UNKNOWN; + linked_shader->Geom.OutputType = PRIM_UNKNOWN; + + /* No in/out qualifiers defined for anything but GLSL 1.50+ + * geometry shaders so far. + */ + if (linked_shader->Stage != MESA_SHADER_GEOMETRY || prog->Version < 150) + return; + + /* From the GLSL 1.50 spec, page 46: + * + * "All geometry shader output layout declarations in a program + * must declare the same layout and same value for + * max_vertices. There must be at least one geometry output + * layout declaration somewhere in a program, but not all + * geometry shaders (compilation units) are required to + * declare it." + */ + + for (unsigned i = 0; i < num_shaders; i++) { + struct gl_shader *shader = shader_list[i]; + + if (shader->Geom.InputType != PRIM_UNKNOWN) { + if (linked_shader->Geom.InputType != PRIM_UNKNOWN && + linked_shader->Geom.InputType != shader->Geom.InputType) { + linker_error(prog, "geometry shader defined with conflicting " + "input types\n"); + return; + } + linked_shader->Geom.InputType = shader->Geom.InputType; + } + + if (shader->Geom.OutputType != PRIM_UNKNOWN) { + if (linked_shader->Geom.OutputType != PRIM_UNKNOWN && + linked_shader->Geom.OutputType != shader->Geom.OutputType) { + linker_error(prog, "geometry shader defined with conflicting " + "output types\n"); + return; + } + linked_shader->Geom.OutputType = shader->Geom.OutputType; + } + + if (shader->Geom.VerticesOut != 0) { + if (linked_shader->Geom.VerticesOut != 0 && + linked_shader->Geom.VerticesOut != shader->Geom.VerticesOut) { + linker_error(prog, "geometry shader defined with conflicting " + "output vertex count (%d and %d)\n", + linked_shader->Geom.VerticesOut, + shader->Geom.VerticesOut); + return; + } + linked_shader->Geom.VerticesOut = shader->Geom.VerticesOut; + } + + if (shader->Geom.Invocations != 0) { + if (linked_shader->Geom.Invocations != 0 && + linked_shader->Geom.Invocations != shader->Geom.Invocations) { + linker_error(prog, "geometry shader defined with conflicting " + "invocation count (%d and %d)\n", + linked_shader->Geom.Invocations, + shader->Geom.Invocations); + return; + } + linked_shader->Geom.Invocations = shader->Geom.Invocations; + } + } + + /* Just do the intrastage -> interstage propagation right now, + * since we already know we're in the right type of shader program + * for doing it. + */ + if (linked_shader->Geom.InputType == PRIM_UNKNOWN) { + linker_error(prog, + "geometry shader didn't declare primitive input type\n"); + return; + } + prog->Geom.InputType = linked_shader->Geom.InputType; + + if (linked_shader->Geom.OutputType == PRIM_UNKNOWN) { + linker_error(prog, + "geometry shader didn't declare primitive output type\n"); + return; + } + prog->Geom.OutputType = linked_shader->Geom.OutputType; + + if (linked_shader->Geom.VerticesOut == 0) { + linker_error(prog, + "geometry shader didn't declare max_vertices\n"); + return; + } + prog->Geom.VerticesOut = linked_shader->Geom.VerticesOut; + + if (linked_shader->Geom.Invocations == 0) + linked_shader->Geom.Invocations = 1; + + prog->Geom.Invocations = linked_shader->Geom.Invocations; +} + + +/** + * Perform cross-validation of compute shader local_size_{x,y,z} layout + * qualifiers for the attached compute shaders, and propagate them to the + * linked CS and linked shader program. + */ +static void +link_cs_input_layout_qualifiers(struct gl_shader_program *prog, + struct gl_shader *linked_shader, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + for (int i = 0; i < 3; i++) + linked_shader->Comp.LocalSize[i] = 0; + + /* This function is called for all shader stages, but it only has an effect + * for compute shaders. + */ + if (linked_shader->Stage != MESA_SHADER_COMPUTE) + return; + + /* From the ARB_compute_shader spec, in the section describing local size + * declarations: + * + * If multiple compute shaders attached to a single program object + * declare local work-group size, the declarations must be identical; + * otherwise a link-time error results. Furthermore, if a program + * object contains any compute shaders, at least one must contain an + * input layout qualifier specifying the local work sizes of the + * program, or a link-time error will occur. + */ + for (unsigned sh = 0; sh < num_shaders; sh++) { + struct gl_shader *shader = shader_list[sh]; + + if (shader->Comp.LocalSize[0] != 0) { + if (linked_shader->Comp.LocalSize[0] != 0) { + for (int i = 0; i < 3; i++) { + if (linked_shader->Comp.LocalSize[i] != + shader->Comp.LocalSize[i]) { + linker_error(prog, "compute shader defined with conflicting " + "local sizes\n"); + return; + } + } + } + for (int i = 0; i < 3; i++) + linked_shader->Comp.LocalSize[i] = shader->Comp.LocalSize[i]; + } + } + + /* Just do the intrastage -> interstage propagation right now, + * since we already know we're in the right type of shader program + * for doing it. + */ + if (linked_shader->Comp.LocalSize[0] == 0) { + linker_error(prog, "compute shader didn't declare local size\n"); + return; + } + for (int i = 0; i < 3; i++) + prog->Comp.LocalSize[i] = linked_shader->Comp.LocalSize[i]; +} + + +/** + * Combine a group of shaders for a single stage to generate a linked shader + * + * \note + * If this function is supplied a single shader, it is cloned, and the new + * shader is returned. + */ +static struct gl_shader * +link_intrastage_shaders(void *mem_ctx, + struct gl_context *ctx, + struct gl_shader_program *prog, + struct gl_shader **shader_list, + unsigned num_shaders) +{ + struct gl_uniform_block *uniform_blocks = NULL; + + /* Check that global variables defined in multiple shaders are consistent. + */ + cross_validate_globals(prog, shader_list, num_shaders, false); + if (!prog->LinkStatus) + return NULL; + + /* Check that interface blocks defined in multiple shaders are consistent. + */ + validate_intrastage_interface_blocks(prog, (const gl_shader **)shader_list, + num_shaders); + if (!prog->LinkStatus) + return NULL; + + /* Link up uniform blocks defined within this stage. */ + const unsigned num_uniform_blocks = + link_uniform_blocks(mem_ctx, ctx, prog, shader_list, num_shaders, + &uniform_blocks); + if (!prog->LinkStatus) + return NULL; + + /* Check that there is only a single definition of each function signature + * across all shaders. + */ + for (unsigned i = 0; i < (num_shaders - 1); i++) { + foreach_in_list(ir_instruction, node, shader_list[i]->ir) { + ir_function *const f = node->as_function(); + + if (f == NULL) + continue; + + for (unsigned j = i + 1; j < num_shaders; j++) { + ir_function *const other = + shader_list[j]->symbols->get_function(f->name); + + /* If the other shader has no function (and therefore no function + * signatures) with the same name, skip to the next shader. + */ + if (other == NULL) + continue; + + foreach_in_list(ir_function_signature, sig, &f->signatures) { + if (!sig->is_defined || sig->is_builtin()) + continue; + + ir_function_signature *other_sig = + other->exact_matching_signature(NULL, &sig->parameters); + + if ((other_sig != NULL) && other_sig->is_defined + && !other_sig->is_builtin()) { + linker_error(prog, "function `%s' is multiply defined\n", + f->name); + return NULL; + } + } + } + } + } + + /* Find the shader that defines main, and make a clone of it. + * + * Starting with the clone, search for undefined references. If one is + * found, find the shader that defines it. Clone the reference and add + * it to the shader. Repeat until there are no undefined references or + * until a reference cannot be resolved. + */ + gl_shader *main = NULL; + for (unsigned i = 0; i < num_shaders; i++) { + if (_mesa_get_main_function_signature(shader_list[i]) != NULL) { + main = shader_list[i]; + break; + } + } + + if (main == NULL) { + linker_error(prog, "%s shader lacks `main'\n", + _mesa_shader_stage_to_string(shader_list[0]->Stage)); + return NULL; + } + + gl_shader *linked = ctx->Driver.NewShader(NULL, 0, main->Type); + linked->ir = new(linked) exec_list; + clone_ir_list(mem_ctx, linked->ir, main->ir); + + linked->BufferInterfaceBlocks = uniform_blocks; + linked->NumBufferInterfaceBlocks = num_uniform_blocks; + ralloc_steal(linked, linked->BufferInterfaceBlocks); + + link_fs_input_layout_qualifiers(prog, linked, shader_list, num_shaders); + link_tcs_out_layout_qualifiers(prog, linked, shader_list, num_shaders); + link_tes_in_layout_qualifiers(prog, linked, shader_list, num_shaders); + link_gs_inout_layout_qualifiers(prog, linked, shader_list, num_shaders); + link_cs_input_layout_qualifiers(prog, linked, shader_list, num_shaders); + + populate_symbol_table(linked); + + /* The pointer to the main function in the final linked shader (i.e., the + * copy of the original shader that contained the main function). + */ + ir_function_signature *const main_sig = + _mesa_get_main_function_signature(linked); + + /* Move any instructions other than variable declarations or function + * declarations into main. + */ + exec_node *insertion_point = + move_non_declarations(linked->ir, (exec_node *) &main_sig->body, false, + linked); + + for (unsigned i = 0; i < num_shaders; i++) { + if (shader_list[i] == main) + continue; + + insertion_point = move_non_declarations(shader_list[i]->ir, + insertion_point, true, linked); + } + + /* Check if any shader needs built-in functions. */ + bool need_builtins = false; + for (unsigned i = 0; i < num_shaders; i++) { + if (shader_list[i]->uses_builtin_functions) { + need_builtins = true; + break; + } + } + + bool ok; + if (need_builtins) { + /* Make a temporary array one larger than shader_list, which will hold + * the built-in function shader as well. + */ + gl_shader **linking_shaders = (gl_shader **) + calloc(num_shaders + 1, sizeof(gl_shader *)); + + ok = linking_shaders != NULL; + + if (ok) { + memcpy(linking_shaders, shader_list, num_shaders * sizeof(gl_shader *)); + linking_shaders[num_shaders] = _mesa_glsl_get_builtin_function_shader(); + + ok = link_function_calls(prog, linked, linking_shaders, num_shaders + 1); + + free(linking_shaders); + } else { + _mesa_error_no_memory(__func__); + } + } else { + ok = link_function_calls(prog, linked, shader_list, num_shaders); + } + + + if (!ok) { + _mesa_delete_shader(ctx, linked); + return NULL; + } + + /* At this point linked should contain all of the linked IR, so + * validate it to make sure nothing went wrong. + */ + validate_ir_tree(linked->ir); + + /* Set the size of geometry shader input arrays */ + if (linked->Stage == MESA_SHADER_GEOMETRY) { + unsigned num_vertices = vertices_per_prim(prog->Geom.InputType); + geom_array_resize_visitor input_resize_visitor(num_vertices, prog); + foreach_in_list(ir_instruction, ir, linked->ir) { + ir->accept(&input_resize_visitor); + } + } + + if (ctx->Const.VertexID_is_zero_based) + lower_vertex_id(linked); + + /* Validate correct usage of barrier() in the tess control shader */ + if (linked->Stage == MESA_SHADER_TESS_CTRL) { + barrier_use_visitor visitor(prog); + foreach_in_list(ir_instruction, ir, linked->ir) { + ir->accept(&visitor); + } + } + + /* Make a pass over all variable declarations to ensure that arrays with + * unspecified sizes have a size specified. The size is inferred from the + * max_array_access field. + */ + array_sizing_visitor v; + v.run(linked->ir); + v.fixup_unnamed_interface_types(); + + return linked; +} + +/** + * Update the sizes of linked shader uniform arrays to the maximum + * array index used. + * + * From page 81 (page 95 of the PDF) of the OpenGL 2.1 spec: + * + * If one or more elements of an array are active, + * GetActiveUniform will return the name of the array in name, + * subject to the restrictions listed above. The type of the array + * is returned in type. The size parameter contains the highest + * array element index used, plus one. The compiler or linker + * determines the highest index used. There will be only one + * active uniform reported by the GL per uniform array. + + */ +static void +update_array_sizes(struct gl_shader_program *prog) +{ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + foreach_in_list(ir_instruction, node, prog->_LinkedShaders[i]->ir) { + ir_variable *const var = node->as_variable(); + + if ((var == NULL) || (var->data.mode != ir_var_uniform) || + !var->type->is_array()) + continue; + + /* GL_ARB_uniform_buffer_object says that std140 uniforms + * will not be eliminated. Since we always do std140, just + * don't resize arrays in UBOs. + * + * Atomic counters are supposed to get deterministic + * locations assigned based on the declaration ordering and + * sizes, array compaction would mess that up. + * + * Subroutine uniforms are not removed. + */ + if (var->is_in_buffer_block() || var->type->contains_atomic() || + var->type->contains_subroutine()) + continue; + + unsigned int size = var->data.max_array_access; + for (unsigned j = 0; j < MESA_SHADER_STAGES; j++) { + if (prog->_LinkedShaders[j] == NULL) + continue; + + foreach_in_list(ir_instruction, node2, prog->_LinkedShaders[j]->ir) { + ir_variable *other_var = node2->as_variable(); + if (!other_var) + continue; + + if (strcmp(var->name, other_var->name) == 0 && + other_var->data.max_array_access > size) { + size = other_var->data.max_array_access; + } + } + } + + if (size + 1 != var->type->length) { + /* If this is a built-in uniform (i.e., it's backed by some + * fixed-function state), adjust the number of state slots to + * match the new array size. The number of slots per array entry + * is not known. It seems safe to assume that the total number of + * slots is an integer multiple of the number of array elements. + * Determine the number of slots per array element by dividing by + * the old (total) size. + */ + const unsigned num_slots = var->get_num_state_slots(); + if (num_slots > 0) { + var->set_num_state_slots((size + 1) + * (num_slots / var->type->length)); + } + + var->type = glsl_type::get_array_instance(var->type->fields.array, + size + 1); + /* FINISHME: We should update the types of array + * dereferences of this variable now. + */ + } + } + } +} + +/** + * Resize tessellation evaluation per-vertex inputs to the size of + * tessellation control per-vertex outputs. + */ +static void +resize_tes_inputs(struct gl_context *ctx, + struct gl_shader_program *prog) +{ + if (prog->_LinkedShaders[MESA_SHADER_TESS_EVAL] == NULL) + return; + + gl_shader *const tcs = prog->_LinkedShaders[MESA_SHADER_TESS_CTRL]; + gl_shader *const tes = prog->_LinkedShaders[MESA_SHADER_TESS_EVAL]; + + /* If no control shader is present, then the TES inputs are statically + * sized to MaxPatchVertices; the actual size of the arrays won't be + * known until draw time. + */ + const int num_vertices = tcs + ? tcs->TessCtrl.VerticesOut + : ctx->Const.MaxPatchVertices; + + tess_eval_array_resize_visitor input_resize_visitor(num_vertices, prog); + foreach_in_list(ir_instruction, ir, tes->ir) { + ir->accept(&input_resize_visitor); + } + + if (tcs) { + /* Convert the gl_PatchVerticesIn system value into a constant, since + * the value is known at this point. + */ + foreach_in_list(ir_instruction, ir, tes->ir) { + ir_variable *var = ir->as_variable(); + if (var && var->data.mode == ir_var_system_value && + var->data.location == SYSTEM_VALUE_VERTICES_IN) { + void *mem_ctx = ralloc_parent(var); + var->data.mode = ir_var_auto; + var->data.location = 0; + var->constant_value = new(mem_ctx) ir_constant(num_vertices); + } + } + } +} + +/** + * Find a contiguous set of available bits in a bitmask. + * + * \param used_mask Bits representing used (1) and unused (0) locations + * \param needed_count Number of contiguous bits needed. + * + * \return + * Base location of the available bits on success or -1 on failure. + */ +int +find_available_slots(unsigned used_mask, unsigned needed_count) +{ + unsigned needed_mask = (1 << needed_count) - 1; + const int max_bit_to_test = (8 * sizeof(used_mask)) - needed_count; + + /* The comparison to 32 is redundant, but without it GCC emits "warning: + * cannot optimize possibly infinite loops" for the loop below. + */ + if ((needed_count == 0) || (max_bit_to_test < 0) || (max_bit_to_test > 32)) + return -1; + + for (int i = 0; i <= max_bit_to_test; i++) { + if ((needed_mask & ~used_mask) == needed_mask) + return i; + + needed_mask <<= 1; + } + + return -1; +} + + +/** + * Assign locations for either VS inputs or FS outputs + * + * \param prog Shader program whose variables need locations assigned + * \param constants Driver specific constant values for the program. + * \param target_index Selector for the program target to receive location + * assignmnets. Must be either \c MESA_SHADER_VERTEX or + * \c MESA_SHADER_FRAGMENT. + * + * \return + * If locations are successfully assigned, true is returned. Otherwise an + * error is emitted to the shader link log and false is returned. + */ +bool +assign_attribute_or_color_locations(gl_shader_program *prog, + struct gl_constants *constants, + unsigned target_index) +{ + /* Maximum number of generic locations. This corresponds to either the + * maximum number of draw buffers or the maximum number of generic + * attributes. + */ + unsigned max_index = (target_index == MESA_SHADER_VERTEX) ? + constants->Program[target_index].MaxAttribs : + MAX2(constants->MaxDrawBuffers, constants->MaxDualSourceDrawBuffers); + + /* Mark invalid locations as being used. + */ + unsigned used_locations = (max_index >= 32) + ? ~0 : ~((1 << max_index) - 1); + unsigned double_storage_locations = 0; + + assert((target_index == MESA_SHADER_VERTEX) + || (target_index == MESA_SHADER_FRAGMENT)); + + gl_shader *const sh = prog->_LinkedShaders[target_index]; + if (sh == NULL) + return true; + + /* Operate in a total of four passes. + * + * 1. Invalidate the location assignments for all vertex shader inputs. + * + * 2. Assign locations for inputs that have user-defined (via + * glBindVertexAttribLocation) locations and outputs that have + * user-defined locations (via glBindFragDataLocation). + * + * 3. Sort the attributes without assigned locations by number of slots + * required in decreasing order. Fragmentation caused by attribute + * locations assigned by the application may prevent large attributes + * from having enough contiguous space. + * + * 4. Assign locations to any inputs without assigned locations. + */ + + const int generic_base = (target_index == MESA_SHADER_VERTEX) + ? (int) VERT_ATTRIB_GENERIC0 : (int) FRAG_RESULT_DATA0; + + const enum ir_variable_mode direction = + (target_index == MESA_SHADER_VERTEX) + ? ir_var_shader_in : ir_var_shader_out; + + + /* Temporary storage for the set of attributes that need locations assigned. + */ + struct temp_attr { + unsigned slots; + ir_variable *var; + + /* Used below in the call to qsort. */ + static int compare(const void *a, const void *b) + { + const temp_attr *const l = (const temp_attr *) a; + const temp_attr *const r = (const temp_attr *) b; + + /* Reversed because we want a descending order sort below. */ + return r->slots - l->slots; + } + } to_assign[16]; + + unsigned num_attr = 0; + + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *const var = node->as_variable(); + + if ((var == NULL) || (var->data.mode != (unsigned) direction)) + continue; + + if (var->data.explicit_location) { + var->data.is_unmatched_generic_inout = 0; + if ((var->data.location >= (int)(max_index + generic_base)) + || (var->data.location < 0)) { + linker_error(prog, + "invalid explicit location %d specified for `%s'\n", + (var->data.location < 0) + ? var->data.location + : var->data.location - generic_base, + var->name); + return false; + } + } else if (target_index == MESA_SHADER_VERTEX) { + unsigned binding; + + if (prog->AttributeBindings->get(binding, var->name)) { + assert(binding >= VERT_ATTRIB_GENERIC0); + var->data.location = binding; + var->data.is_unmatched_generic_inout = 0; + } + } else if (target_index == MESA_SHADER_FRAGMENT) { + unsigned binding; + unsigned index; + + if (prog->FragDataBindings->get(binding, var->name)) { + assert(binding >= FRAG_RESULT_DATA0); + var->data.location = binding; + var->data.is_unmatched_generic_inout = 0; + + if (prog->FragDataIndexBindings->get(index, var->name)) { + var->data.index = index; + } + } + } + + /* From GL4.5 core spec, section 15.2 (Shader Execution): + * + * "Output binding assignments will cause LinkProgram to fail: + * ... + * If the program has an active output assigned to a location greater + * than or equal to the value of MAX_DUAL_SOURCE_DRAW_BUFFERS and has + * an active output assigned an index greater than or equal to one;" + */ + if (target_index == MESA_SHADER_FRAGMENT && var->data.index >= 1 && + var->data.location - generic_base >= + (int) constants->MaxDualSourceDrawBuffers) { + linker_error(prog, + "output location %d >= GL_MAX_DUAL_SOURCE_DRAW_BUFFERS " + "with index %u for %s\n", + var->data.location - generic_base, var->data.index, + var->name); + return false; + } + + const unsigned slots = var->type->count_attribute_slots(target_index == MESA_SHADER_VERTEX ? true : false); + + /* If the variable is not a built-in and has a location statically + * assigned in the shader (presumably via a layout qualifier), make sure + * that it doesn't collide with other assigned locations. Otherwise, + * add it to the list of variables that need linker-assigned locations. + */ + if (var->data.location != -1) { + if (var->data.location >= generic_base && var->data.index < 1) { + /* From page 61 of the OpenGL 4.0 spec: + * + * "LinkProgram will fail if the attribute bindings assigned + * by BindAttribLocation do not leave not enough space to + * assign a location for an active matrix attribute or an + * active attribute array, both of which require multiple + * contiguous generic attributes." + * + * I think above text prohibits the aliasing of explicit and + * automatic assignments. But, aliasing is allowed in manual + * assignments of attribute locations. See below comments for + * the details. + * + * From OpenGL 4.0 spec, page 61: + * + * "It is possible for an application to bind more than one + * attribute name to the same location. This is referred to as + * aliasing. This will only work if only one of the aliased + * attributes is active in the executable program, or if no + * path through the shader consumes more than one attribute of + * a set of attributes aliased to the same location. A link + * error can occur if the linker determines that every path + * through the shader consumes multiple aliased attributes, + * but implementations are not required to generate an error + * in this case." + * + * From GLSL 4.30 spec, page 54: + * + * "A program will fail to link if any two non-vertex shader + * input variables are assigned to the same location. For + * vertex shaders, multiple input variables may be assigned + * to the same location using either layout qualifiers or via + * the OpenGL API. However, such aliasing is intended only to + * support vertex shaders where each execution path accesses + * at most one input per each location. Implementations are + * permitted, but not required, to generate link-time errors + * if they detect that every path through the vertex shader + * executable accesses multiple inputs assigned to any single + * location. For all shader types, a program will fail to link + * if explicit location assignments leave the linker unable + * to find space for other variables without explicit + * assignments." + * + * From OpenGL ES 3.0 spec, page 56: + * + * "Binding more than one attribute name to the same location + * is referred to as aliasing, and is not permitted in OpenGL + * ES Shading Language 3.00 vertex shaders. LinkProgram will + * fail when this condition exists. However, aliasing is + * possible in OpenGL ES Shading Language 1.00 vertex shaders. + * This will only work if only one of the aliased attributes + * is active in the executable program, or if no path through + * the shader consumes more than one attribute of a set of + * attributes aliased to the same location. A link error can + * occur if the linker determines that every path through the + * shader consumes multiple aliased attributes, but implemen- + * tations are not required to generate an error in this case." + * + * After looking at above references from OpenGL, OpenGL ES and + * GLSL specifications, we allow aliasing of vertex input variables + * in: OpenGL 2.0 (and above) and OpenGL ES 2.0. + * + * NOTE: This is not required by the spec but its worth mentioning + * here that we're not doing anything to make sure that no path + * through the vertex shader executable accesses multiple inputs + * assigned to any single location. + */ + + /* Mask representing the contiguous slots that will be used by + * this attribute. + */ + const unsigned attr = var->data.location - generic_base; + const unsigned use_mask = (1 << slots) - 1; + const char *const string = (target_index == MESA_SHADER_VERTEX) + ? "vertex shader input" : "fragment shader output"; + + /* Generate a link error if the requested locations for this + * attribute exceed the maximum allowed attribute location. + */ + if (attr + slots > max_index) { + linker_error(prog, + "insufficient contiguous locations " + "available for %s `%s' %d %d %d\n", string, + var->name, used_locations, use_mask, attr); + return false; + } + + /* Generate a link error if the set of bits requested for this + * attribute overlaps any previously allocated bits. + */ + if ((~(use_mask << attr) & used_locations) != used_locations) { + if (target_index == MESA_SHADER_FRAGMENT || + (prog->IsES && prog->Version >= 300)) { + linker_error(prog, + "overlapping location is assigned " + "to %s `%s' %d %d %d\n", string, + var->name, used_locations, use_mask, attr); + return false; + } else { + linker_warning(prog, + "overlapping location is assigned " + "to %s `%s' %d %d %d\n", string, + var->name, used_locations, use_mask, attr); + } + } + + used_locations |= (use_mask << attr); + + /* From the GL 4.5 core spec, section 11.1.1 (Vertex Attributes): + * + * "A program with more than the value of MAX_VERTEX_ATTRIBS + * active attribute variables may fail to link, unless + * device-dependent optimizations are able to make the program + * fit within available hardware resources. For the purposes + * of this test, attribute variables of the type dvec3, dvec4, + * dmat2x3, dmat2x4, dmat3, dmat3x4, dmat4x3, and dmat4 may + * count as consuming twice as many attributes as equivalent + * single-precision types. While these types use the same number + * of generic attributes as their single-precision equivalents, + * implementations are permitted to consume two single-precision + * vectors of internal storage for each three- or four-component + * double-precision vector." + * + * Mark this attribute slot as taking up twice as much space + * so we can count it properly against limits. According to + * issue (3) of the GL_ARB_vertex_attrib_64bit behavior, this + * is optional behavior, but it seems preferable. + */ + if (var->type->without_array()->is_dual_slot_double()) + double_storage_locations |= (use_mask << attr); + } + + continue; + } + + to_assign[num_attr].slots = slots; + to_assign[num_attr].var = var; + num_attr++; + } + + if (target_index == MESA_SHADER_VERTEX) { + unsigned total_attribs_size = + _mesa_bitcount(used_locations & ((1 << max_index) - 1)) + + _mesa_bitcount(double_storage_locations); + if (total_attribs_size > max_index) { + linker_error(prog, + "attempt to use %d vertex attribute slots only %d available ", + total_attribs_size, max_index); + return false; + } + } + + /* If all of the attributes were assigned locations by the application (or + * are built-in attributes with fixed locations), return early. This should + * be the common case. + */ + if (num_attr == 0) + return true; + + qsort(to_assign, num_attr, sizeof(to_assign[0]), temp_attr::compare); + + if (target_index == MESA_SHADER_VERTEX) { + /* VERT_ATTRIB_GENERIC0 is a pseudo-alias for VERT_ATTRIB_POS. It can + * only be explicitly assigned by via glBindAttribLocation. Mark it as + * reserved to prevent it from being automatically allocated below. + */ + find_deref_visitor find("gl_Vertex"); + find.run(sh->ir); + if (find.variable_found()) + used_locations |= (1 << 0); + } + + for (unsigned i = 0; i < num_attr; i++) { + /* Mask representing the contiguous slots that will be used by this + * attribute. + */ + const unsigned use_mask = (1 << to_assign[i].slots) - 1; + + int location = find_available_slots(used_locations, to_assign[i].slots); + + if (location < 0) { + const char *const string = (target_index == MESA_SHADER_VERTEX) + ? "vertex shader input" : "fragment shader output"; + + linker_error(prog, + "insufficient contiguous locations " + "available for %s `%s'\n", + string, to_assign[i].var->name); + return false; + } + + to_assign[i].var->data.location = generic_base + location; + to_assign[i].var->data.is_unmatched_generic_inout = 0; + used_locations |= (use_mask << location); + } + + return true; +} + +/** + * Match explicit locations of outputs to inputs and deactivate the + * unmatch flag if found so we don't optimise them away. + */ +static void +match_explicit_outputs_to_inputs(struct gl_shader_program *prog, + gl_shader *producer, + gl_shader *consumer) +{ + glsl_symbol_table parameters; + ir_variable *explicit_locations[MAX_VARYING] = { NULL }; + + /* Find all shader outputs in the "producer" stage. + */ + foreach_in_list(ir_instruction, node, producer->ir) { + ir_variable *const var = node->as_variable(); + + if ((var == NULL) || (var->data.mode != ir_var_shader_out)) + continue; + + if (var->data.explicit_location && + var->data.location >= VARYING_SLOT_VAR0) { + const unsigned idx = var->data.location - VARYING_SLOT_VAR0; + if (explicit_locations[idx] == NULL) + explicit_locations[idx] = var; + } + } + + /* Match inputs to outputs */ + foreach_in_list(ir_instruction, node, consumer->ir) { + ir_variable *const input = node->as_variable(); + + if ((input == NULL) || (input->data.mode != ir_var_shader_in)) + continue; + + ir_variable *output = NULL; + if (input->data.explicit_location + && input->data.location >= VARYING_SLOT_VAR0) { + output = explicit_locations[input->data.location - VARYING_SLOT_VAR0]; + + if (output != NULL){ + input->data.is_unmatched_generic_inout = 0; + output->data.is_unmatched_generic_inout = 0; + } + } + } +} + +/** + * Store the gl_FragDepth layout in the gl_shader_program struct. + */ +static void +store_fragdepth_layout(struct gl_shader_program *prog) +{ + if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] == NULL) { + return; + } + + struct exec_list *ir = prog->_LinkedShaders[MESA_SHADER_FRAGMENT]->ir; + + /* We don't look up the gl_FragDepth symbol directly because if + * gl_FragDepth is not used in the shader, it's removed from the IR. + * However, the symbol won't be removed from the symbol table. + * + * We're only interested in the cases where the variable is NOT removed + * from the IR. + */ + foreach_in_list(ir_instruction, node, ir) { + ir_variable *const var = node->as_variable(); + + if (var == NULL || var->data.mode != ir_var_shader_out) { + continue; + } + + if (strcmp(var->name, "gl_FragDepth") == 0) { + switch (var->data.depth_layout) { + case ir_depth_layout_none: + prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_NONE; + return; + case ir_depth_layout_any: + prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_ANY; + return; + case ir_depth_layout_greater: + prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_GREATER; + return; + case ir_depth_layout_less: + prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_LESS; + return; + case ir_depth_layout_unchanged: + prog->FragDepthLayout = FRAG_DEPTH_LAYOUT_UNCHANGED; + return; + default: + assert(0); + return; + } + } + } +} + +/** + * Validate the resources used by a program versus the implementation limits + */ +static void +check_resources(struct gl_context *ctx, struct gl_shader_program *prog) +{ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + + if (sh == NULL) + continue; + + if (sh->num_samplers > ctx->Const.Program[i].MaxTextureImageUnits) { + linker_error(prog, "Too many %s shader texture samplers\n", + _mesa_shader_stage_to_string(i)); + } + + if (sh->num_uniform_components > + ctx->Const.Program[i].MaxUniformComponents) { + if (ctx->Const.GLSLSkipStrictMaxUniformLimitCheck) { + linker_warning(prog, "Too many %s shader default uniform block " + "components, but the driver will try to optimize " + "them out; this is non-portable out-of-spec " + "behavior\n", + _mesa_shader_stage_to_string(i)); + } else { + linker_error(prog, "Too many %s shader default uniform block " + "components\n", + _mesa_shader_stage_to_string(i)); + } + } + + if (sh->num_combined_uniform_components > + ctx->Const.Program[i].MaxCombinedUniformComponents) { + if (ctx->Const.GLSLSkipStrictMaxUniformLimitCheck) { + linker_warning(prog, "Too many %s shader uniform components, " + "but the driver will try to optimize them out; " + "this is non-portable out-of-spec behavior\n", + _mesa_shader_stage_to_string(i)); + } else { + linker_error(prog, "Too many %s shader uniform components\n", + _mesa_shader_stage_to_string(i)); + } + } + } + + unsigned blocks[MESA_SHADER_STAGES] = {0}; + unsigned total_uniform_blocks = 0; + unsigned shader_blocks[MESA_SHADER_STAGES] = {0}; + unsigned total_shader_storage_blocks = 0; + + for (unsigned i = 0; i < prog->NumBufferInterfaceBlocks; i++) { + /* Don't check SSBOs for Uniform Block Size */ + if (!prog->BufferInterfaceBlocks[i].IsShaderStorage && + prog->BufferInterfaceBlocks[i].UniformBufferSize > ctx->Const.MaxUniformBlockSize) { + linker_error(prog, "Uniform block %s too big (%d/%d)\n", + prog->BufferInterfaceBlocks[i].Name, + prog->BufferInterfaceBlocks[i].UniformBufferSize, + ctx->Const.MaxUniformBlockSize); + } + + if (prog->BufferInterfaceBlocks[i].IsShaderStorage && + prog->BufferInterfaceBlocks[i].UniformBufferSize > ctx->Const.MaxShaderStorageBlockSize) { + linker_error(prog, "Shader storage block %s too big (%d/%d)\n", + prog->BufferInterfaceBlocks[i].Name, + prog->BufferInterfaceBlocks[i].UniformBufferSize, + ctx->Const.MaxShaderStorageBlockSize); + } + + for (unsigned j = 0; j < MESA_SHADER_STAGES; j++) { + if (prog->InterfaceBlockStageIndex[j][i] != -1) { + struct gl_shader *sh = prog->_LinkedShaders[j]; + int stage_index = prog->InterfaceBlockStageIndex[j][i]; + if (sh && sh->BufferInterfaceBlocks[stage_index].IsShaderStorage) { + shader_blocks[j]++; + total_shader_storage_blocks++; + } else { + blocks[j]++; + total_uniform_blocks++; + } + } + } + + if (total_uniform_blocks > ctx->Const.MaxCombinedUniformBlocks) { + linker_error(prog, "Too many combined uniform blocks (%d/%d)\n", + total_uniform_blocks, + ctx->Const.MaxCombinedUniformBlocks); + } else { + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + const unsigned max_uniform_blocks = + ctx->Const.Program[i].MaxUniformBlocks; + if (blocks[i] > max_uniform_blocks) { + linker_error(prog, "Too many %s uniform blocks (%d/%d)\n", + _mesa_shader_stage_to_string(i), + blocks[i], + max_uniform_blocks); + break; + } + } + } + + if (total_shader_storage_blocks > ctx->Const.MaxCombinedShaderStorageBlocks) { + linker_error(prog, "Too many combined shader storage blocks (%d/%d)\n", + total_shader_storage_blocks, + ctx->Const.MaxCombinedShaderStorageBlocks); + } else { + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + const unsigned max_shader_storage_blocks = + ctx->Const.Program[i].MaxShaderStorageBlocks; + if (shader_blocks[i] > max_shader_storage_blocks) { + linker_error(prog, "Too many %s shader storage blocks (%d/%d)\n", + _mesa_shader_stage_to_string(i), + shader_blocks[i], + max_shader_storage_blocks); + break; + } + } + } + } +} + +static void +link_calculate_subroutine_compat(struct gl_shader_program *prog) +{ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + int count; + if (!sh) + continue; + + for (unsigned j = 0; j < sh->NumSubroutineUniformRemapTable; j++) { + struct gl_uniform_storage *uni = sh->SubroutineUniformRemapTable[j]; + + if (!uni) + continue; + + count = 0; + for (unsigned f = 0; f < sh->NumSubroutineFunctions; f++) { + struct gl_subroutine_function *fn = &sh->SubroutineFunctions[f]; + for (int k = 0; k < fn->num_compat_types; k++) { + if (fn->types[k] == uni->type) { + count++; + break; + } + } + } + uni->num_compatible_subroutines = count; + } + } +} + +static void +check_subroutine_resources(struct gl_shader_program *prog) +{ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + + if (sh) { + if (sh->NumSubroutineUniformRemapTable > MAX_SUBROUTINE_UNIFORM_LOCATIONS) + linker_error(prog, "Too many %s shader subroutine uniforms\n", + _mesa_shader_stage_to_string(i)); + } + } +} +/** + * Validate shader image resources. + */ +static void +check_image_resources(struct gl_context *ctx, struct gl_shader_program *prog) +{ + unsigned total_image_units = 0; + unsigned fragment_outputs = 0; + unsigned total_shader_storage_blocks = 0; + + if (!ctx->Extensions.ARB_shader_image_load_store) + return; + + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + + if (sh) { + if (sh->NumImages > ctx->Const.Program[i].MaxImageUniforms) + linker_error(prog, "Too many %s shader image uniforms (%u > %u)\n", + _mesa_shader_stage_to_string(i), sh->NumImages, + ctx->Const.Program[i].MaxImageUniforms); + + total_image_units += sh->NumImages; + + for (unsigned j = 0; j < prog->NumBufferInterfaceBlocks; j++) { + int stage_index = prog->InterfaceBlockStageIndex[i][j]; + if (stage_index != -1 && sh->BufferInterfaceBlocks[stage_index].IsShaderStorage) + total_shader_storage_blocks++; + } + + if (i == MESA_SHADER_FRAGMENT) { + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *var = node->as_variable(); + if (var && var->data.mode == ir_var_shader_out) + /* since there are no double fs outputs - pass false */ + fragment_outputs += var->type->count_attribute_slots(false); + } + } + } + } + + if (total_image_units > ctx->Const.MaxCombinedImageUniforms) + linker_error(prog, "Too many combined image uniforms\n"); + + if (total_image_units + fragment_outputs + total_shader_storage_blocks > + ctx->Const.MaxCombinedShaderOutputResources) + linker_error(prog, "Too many combined image uniforms, shader storage " + " buffers and fragment outputs\n"); +} + + +/** + * Initializes explicit location slots to INACTIVE_UNIFORM_EXPLICIT_LOCATION + * for a variable, checks for overlaps between other uniforms using explicit + * locations. + */ +static bool +reserve_explicit_locations(struct gl_shader_program *prog, + string_to_uint_map *map, ir_variable *var) +{ + unsigned slots = var->type->uniform_locations(); + unsigned max_loc = var->data.location + slots - 1; + + /* Resize remap table if locations do not fit in the current one. */ + if (max_loc + 1 > prog->NumUniformRemapTable) { + prog->UniformRemapTable = + reralloc(prog, prog->UniformRemapTable, + gl_uniform_storage *, + max_loc + 1); + + if (!prog->UniformRemapTable) { + linker_error(prog, "Out of memory during linking.\n"); + return false; + } + + /* Initialize allocated space. */ + for (unsigned i = prog->NumUniformRemapTable; i < max_loc + 1; i++) + prog->UniformRemapTable[i] = NULL; + + prog->NumUniformRemapTable = max_loc + 1; + } + + for (unsigned i = 0; i < slots; i++) { + unsigned loc = var->data.location + i; + + /* Check if location is already used. */ + if (prog->UniformRemapTable[loc] == INACTIVE_UNIFORM_EXPLICIT_LOCATION) { + + /* Possibly same uniform from a different stage, this is ok. */ + unsigned hash_loc; + if (map->get(hash_loc, var->name) && hash_loc == loc - i) + continue; + + /* ARB_explicit_uniform_location specification states: + * + * "No two default-block uniform variables in the program can have + * the same location, even if they are unused, otherwise a compiler + * or linker error will be generated." + */ + linker_error(prog, + "location qualifier for uniform %s overlaps " + "previously used location\n", + var->name); + return false; + } + + /* Initialize location as inactive before optimization + * rounds and location assignment. + */ + prog->UniformRemapTable[loc] = INACTIVE_UNIFORM_EXPLICIT_LOCATION; + } + + /* Note, base location used for arrays. */ + map->put(var->data.location, var->name); + + return true; +} + +static bool +reserve_subroutine_explicit_locations(struct gl_shader_program *prog, + struct gl_shader *sh, + ir_variable *var) +{ + unsigned slots = var->type->uniform_locations(); + unsigned max_loc = var->data.location + slots - 1; + + /* Resize remap table if locations do not fit in the current one. */ + if (max_loc + 1 > sh->NumSubroutineUniformRemapTable) { + sh->SubroutineUniformRemapTable = + reralloc(sh, sh->SubroutineUniformRemapTable, + gl_uniform_storage *, + max_loc + 1); + + if (!sh->SubroutineUniformRemapTable) { + linker_error(prog, "Out of memory during linking.\n"); + return false; + } + + /* Initialize allocated space. */ + for (unsigned i = sh->NumSubroutineUniformRemapTable; i < max_loc + 1; i++) + sh->SubroutineUniformRemapTable[i] = NULL; + + sh->NumSubroutineUniformRemapTable = max_loc + 1; + } + + for (unsigned i = 0; i < slots; i++) { + unsigned loc = var->data.location + i; + + /* Check if location is already used. */ + if (sh->SubroutineUniformRemapTable[loc] == INACTIVE_UNIFORM_EXPLICIT_LOCATION) { + + /* ARB_explicit_uniform_location specification states: + * "No two subroutine uniform variables can have the same location + * in the same shader stage, otherwise a compiler or linker error + * will be generated." + */ + linker_error(prog, + "location qualifier for uniform %s overlaps " + "previously used location\n", + var->name); + return false; + } + + /* Initialize location as inactive before optimization + * rounds and location assignment. + */ + sh->SubroutineUniformRemapTable[loc] = INACTIVE_UNIFORM_EXPLICIT_LOCATION; + } + + return true; +} +/** + * Check and reserve all explicit uniform locations, called before + * any optimizations happen to handle also inactive uniforms and + * inactive array elements that may get trimmed away. + */ +static void +check_explicit_uniform_locations(struct gl_context *ctx, + struct gl_shader_program *prog) +{ + if (!ctx->Extensions.ARB_explicit_uniform_location) + return; + + /* This map is used to detect if overlapping explicit locations + * occur with the same uniform (from different stage) or a different one. + */ + string_to_uint_map *uniform_map = new string_to_uint_map; + + if (!uniform_map) { + linker_error(prog, "Out of memory during linking.\n"); + return; + } + + unsigned entries_total = 0; + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = prog->_LinkedShaders[i]; + + if (!sh) + continue; + + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *var = node->as_variable(); + if (!var || var->data.mode != ir_var_uniform) + continue; + + entries_total += var->type->uniform_locations(); + + if (var->data.explicit_location) { + bool ret; + if (var->type->without_array()->is_subroutine()) + ret = reserve_subroutine_explicit_locations(prog, sh, var); + else + ret = reserve_explicit_locations(prog, uniform_map, var); + if (!ret) { + delete uniform_map; + return; + } + } + } + } + + /* Verify that total amount of entries for explicit and implicit locations + * is less than MAX_UNIFORM_LOCATIONS. + */ + if (entries_total >= ctx->Const.MaxUserAssignableUniformLocations) { + linker_error(prog, "count of uniform locations >= MAX_UNIFORM_LOCATIONS" + "(%u >= %u)", entries_total, + ctx->Const.MaxUserAssignableUniformLocations); + } + delete uniform_map; +} + +static bool +should_add_buffer_variable(struct gl_shader_program *shProg, + GLenum type, const char *name) +{ + bool found_interface = false; + unsigned block_name_len = 0; + const char *block_name_dot = strchr(name, '.'); + + /* These rules only apply to buffer variables. So we return + * true for the rest of types. + */ + if (type != GL_BUFFER_VARIABLE) + return true; + + for (unsigned i = 0; i < shProg->NumBufferInterfaceBlocks; i++) { + const char *block_name = shProg->BufferInterfaceBlocks[i].Name; + block_name_len = strlen(block_name); + + const char *block_square_bracket = strchr(block_name, '['); + if (block_square_bracket) { + /* The block is part of an array of named interfaces, + * for the name comparison we ignore the "[x]" part. + */ + block_name_len -= strlen(block_square_bracket); + } + + if (block_name_dot) { + /* Check if the variable name starts with the interface + * name. The interface name (if present) should have the + * length than the interface block name we are comparing to. + */ + unsigned len = strlen(name) - strlen(block_name_dot); + if (len != block_name_len) + continue; + } + + if (strncmp(block_name, name, block_name_len) == 0) { + found_interface = true; + break; + } + } + + /* We remove the interface name from the buffer variable name, + * including the dot that follows it. + */ + if (found_interface) + name = name + block_name_len + 1; + + /* From: ARB_program_interface_query extension: + * + * "For an active shader storage block member declared as an array, an + * entry will be generated only for the first array element, regardless + * of its type. For arrays of aggregate types, the enumeration rules are + * applied recursively for the single enumerated array element. + */ + const char *struct_first_dot = strchr(name, '.'); + const char *first_square_bracket = strchr(name, '['); + + /* The buffer variable is on top level and it is not an array */ + if (!first_square_bracket) { + return true; + /* The shader storage block member is a struct, then generate the entry */ + } else if (struct_first_dot && struct_first_dot < first_square_bracket) { + return true; + } else { + /* Shader storage block member is an array, only generate an entry for the + * first array element. + */ + if (strncmp(first_square_bracket, "[0]", 3) == 0) + return true; + } + + return false; +} + +static bool +add_program_resource(struct gl_shader_program *prog, GLenum type, + const void *data, uint8_t stages) +{ + assert(data); + + /* If resource already exists, do not add it again. */ + for (unsigned i = 0; i < prog->NumProgramResourceList; i++) + if (prog->ProgramResourceList[i].Data == data) + return true; + + prog->ProgramResourceList = + reralloc(prog, + prog->ProgramResourceList, + gl_program_resource, + prog->NumProgramResourceList + 1); + + if (!prog->ProgramResourceList) { + linker_error(prog, "Out of memory during linking.\n"); + return false; + } + + struct gl_program_resource *res = + &prog->ProgramResourceList[prog->NumProgramResourceList]; + + res->Type = type; + res->Data = data; + res->StageReferences = stages; + + prog->NumProgramResourceList++; + + return true; +} + +/* Function checks if a variable var is a packed varying and + * if given name is part of packed varying's list. + * + * If a variable is a packed varying, it has a name like + * 'packed:a,b,c' where a, b and c are separate variables. + */ +static bool +included_in_packed_varying(ir_variable *var, const char *name) +{ + if (strncmp(var->name, "packed:", 7) != 0) + return false; + + char *list = strdup(var->name + 7); + assert(list); + + bool found = false; + char *saveptr; + char *token = strtok_r(list, ",", &saveptr); + while (token) { + if (strcmp(token, name) == 0) { + found = true; + break; + } + token = strtok_r(NULL, ",", &saveptr); + } + free(list); + return found; +} + +/** + * Function builds a stage reference bitmask from variable name. + */ +static uint8_t +build_stageref(struct gl_shader_program *shProg, const char *name, + unsigned mode) +{ + uint8_t stages = 0; + + /* Note, that we assume MAX 8 stages, if there will be more stages, type + * used for reference mask in gl_program_resource will need to be changed. + */ + assert(MESA_SHADER_STAGES < 8); + + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = shProg->_LinkedShaders[i]; + if (!sh) + continue; + + /* Shader symbol table may contain variables that have + * been optimized away. Search IR for the variable instead. + */ + foreach_in_list(ir_instruction, node, sh->ir) { + ir_variable *var = node->as_variable(); + if (var) { + unsigned baselen = strlen(var->name); + + if (included_in_packed_varying(var, name)) { + stages |= (1 << i); + break; + } + + /* Type needs to match if specified, otherwise we might + * pick a variable with same name but different interface. + */ + if (var->data.mode != mode) + continue; + + if (strncmp(var->name, name, baselen) == 0) { + /* Check for exact name matches but also check for arrays and + * structs. + */ + if (name[baselen] == '\0' || + name[baselen] == '[' || + name[baselen] == '.') { + stages |= (1 << i); + break; + } + } + } + } + } + return stages; +} + +/** + * Create gl_shader_variable from ir_variable class. + */ +static gl_shader_variable * +create_shader_variable(struct gl_shader_program *shProg, const ir_variable *in) +{ + gl_shader_variable *out = ralloc(shProg, struct gl_shader_variable); + if (!out) + return NULL; + + out->type = in->type; + out->name = ralloc_strdup(shProg, in->name); + + if (!out->name) + return NULL; + + out->location = in->data.location; + out->index = in->data.index; + out->patch = in->data.patch; + out->mode = in->data.mode; + + return out; +} + +static bool +add_interface_variables(struct gl_shader_program *shProg, + exec_list *ir, GLenum programInterface) +{ + foreach_in_list(ir_instruction, node, ir) { + ir_variable *var = node->as_variable(); + uint8_t mask = 0; + + if (!var) + continue; + + switch (var->data.mode) { + /* From GL 4.3 core spec, section 11.1.1 (Vertex Attributes): + * "For GetActiveAttrib, all active vertex shader input variables + * are enumerated, including the special built-in inputs gl_VertexID + * and gl_InstanceID." + */ + case ir_var_system_value: + if (var->data.location != SYSTEM_VALUE_VERTEX_ID && + var->data.location != SYSTEM_VALUE_VERTEX_ID_ZERO_BASE && + var->data.location != SYSTEM_VALUE_INSTANCE_ID) + continue; + /* Mark special built-in inputs referenced by the vertex stage so + * that they are considered active by the shader queries. + */ + mask = (1 << (MESA_SHADER_VERTEX)); + /* FALLTHROUGH */ + case ir_var_shader_in: + if (programInterface != GL_PROGRAM_INPUT) + continue; + break; + case ir_var_shader_out: + if (programInterface != GL_PROGRAM_OUTPUT) + continue; + break; + default: + continue; + }; + + /* Skip packed varyings, packed varyings are handled separately + * by add_packed_varyings. + */ + if (strncmp(var->name, "packed:", 7) == 0) + continue; + + /* Skip fragdata arrays, these are handled separately + * by add_fragdata_arrays. + */ + if (strncmp(var->name, "gl_out_FragData", 15) == 0) + continue; + + gl_shader_variable *sha_v = create_shader_variable(shProg, var); + if (!sha_v) + return false; + + if (!add_program_resource(shProg, programInterface, sha_v, + build_stageref(shProg, sha_v->name, + sha_v->mode) | mask)) + return false; + } + return true; +} + +static bool +add_packed_varyings(struct gl_shader_program *shProg, int stage, GLenum type) +{ + struct gl_shader *sh = shProg->_LinkedShaders[stage]; + GLenum iface; + + if (!sh || !sh->packed_varyings) + return true; + + foreach_in_list(ir_instruction, node, sh->packed_varyings) { + ir_variable *var = node->as_variable(); + if (var) { + switch (var->data.mode) { + case ir_var_shader_in: + iface = GL_PROGRAM_INPUT; + break; + case ir_var_shader_out: + iface = GL_PROGRAM_OUTPUT; + break; + default: + unreachable("unexpected type"); + } + + if (type == iface) { + gl_shader_variable *sha_v = create_shader_variable(shProg, var); + if (!sha_v) + return false; + if (!add_program_resource(shProg, iface, sha_v, + build_stageref(shProg, sha_v->name, + sha_v->mode))) + return false; + } + } + } + return true; +} + +static bool +add_fragdata_arrays(struct gl_shader_program *shProg) +{ + struct gl_shader *sh = shProg->_LinkedShaders[MESA_SHADER_FRAGMENT]; + + if (!sh || !sh->fragdata_arrays) + return true; + + foreach_in_list(ir_instruction, node, sh->fragdata_arrays) { + ir_variable *var = node->as_variable(); + if (var) { + assert(var->data.mode == ir_var_shader_out); + gl_shader_variable *sha_v = create_shader_variable(shProg, var); + if (!sha_v) + return false; + if (!add_program_resource(shProg, GL_PROGRAM_OUTPUT, sha_v, + 1 << MESA_SHADER_FRAGMENT)) + return false; + } + } + return true; +} + +static char* +get_top_level_name(const char *name) +{ + const char *first_dot = strchr(name, '.'); + const char *first_square_bracket = strchr(name, '['); + int name_size = 0; + /* From ARB_program_interface_query spec: + * + * "For the property TOP_LEVEL_ARRAY_SIZE, a single integer identifying the + * number of active array elements of the top-level shader storage block + * member containing to the active variable is written to <params>. If the + * top-level block member is not declared as an array, the value one is + * written to <params>. If the top-level block member is an array with no + * declared size, the value zero is written to <params>. + */ + + /* The buffer variable is on top level.*/ + if (!first_square_bracket && !first_dot) + name_size = strlen(name); + else if ((!first_square_bracket || + (first_dot && first_dot < first_square_bracket))) + name_size = first_dot - name; + else + name_size = first_square_bracket - name; + + return strndup(name, name_size); +} + +static char* +get_var_name(const char *name) +{ + const char *first_dot = strchr(name, '.'); + + if (!first_dot) + return strdup(name); + + return strndup(first_dot+1, strlen(first_dot) - 1); +} + +static bool +is_top_level_shader_storage_block_member(const char* name, + const char* interface_name, + const char* field_name) +{ + bool result = false; + + /* If the given variable is already a top-level shader storage + * block member, then return array_size = 1. + * We could have two possibilities: if we have an instanced + * shader storage block or not instanced. + * + * For the first, we check create a name as it was in top level and + * compare it with the real name. If they are the same, then + * the variable is already at top-level. + * + * Full instanced name is: interface name + '.' + var name + + * NULL character + */ + int name_length = strlen(interface_name) + 1 + strlen(field_name) + 1; + char *full_instanced_name = (char *) calloc(name_length, sizeof(char)); + if (!full_instanced_name) { + fprintf(stderr, "%s: Cannot allocate space for name\n", __func__); + return false; + } + + snprintf(full_instanced_name, name_length, "%s.%s", + interface_name, field_name); + + /* Check if its top-level shader storage block member of an + * instanced interface block, or of a unnamed interface block. + */ + if (strcmp(name, full_instanced_name) == 0 || + strcmp(name, field_name) == 0) + result = true; + + free(full_instanced_name); + return result; +} + +static int +get_array_size(struct gl_uniform_storage *uni, const glsl_struct_field *field, + char *interface_name, char *var_name) +{ + /* From GL_ARB_program_interface_query spec: + * + * "For the property TOP_LEVEL_ARRAY_SIZE, a single integer + * identifying the number of active array elements of the top-level + * shader storage block member containing to the active variable is + * written to <params>. If the top-level block member is not + * declared as an array, the value one is written to <params>. If + * the top-level block member is an array with no declared size, + * the value zero is written to <params>. + */ + if (is_top_level_shader_storage_block_member(uni->name, + interface_name, + var_name)) + return 1; + else if (field->type->is_unsized_array()) + return 0; + else if (field->type->is_array()) + return field->type->length; + + return 1; +} + +static int +get_array_stride(struct gl_uniform_storage *uni, const glsl_type *interface, + const glsl_struct_field *field, char *interface_name, + char *var_name) +{ + /* From GL_ARB_program_interface_query: + * + * "For the property TOP_LEVEL_ARRAY_STRIDE, a single integer + * identifying the stride between array elements of the top-level + * shader storage block member containing the active variable is + * written to <params>. For top-level block members declared as + * arrays, the value written is the difference, in basic machine + * units, between the offsets of the active variable for + * consecutive elements in the top-level array. For top-level + * block members not declared as an array, zero is written to + * <params>." + */ + if (field->type->is_array()) { + const enum glsl_matrix_layout matrix_layout = + glsl_matrix_layout(field->matrix_layout); + bool row_major = matrix_layout == GLSL_MATRIX_LAYOUT_ROW_MAJOR; + const glsl_type *array_type = field->type->fields.array; + + if (is_top_level_shader_storage_block_member(uni->name, + interface_name, + var_name)) + return 0; + + if (interface->interface_packing != GLSL_INTERFACE_PACKING_STD430) { + if (array_type->is_record() || array_type->is_array()) + return glsl_align(array_type->std140_size(row_major), 16); + else + return MAX2(array_type->std140_base_alignment(row_major), 16); + } else { + return array_type->std430_array_stride(row_major); + } + } + return 0; +} + +static void +calculate_array_size_and_stride(struct gl_shader_program *shProg, + struct gl_uniform_storage *uni) +{ + int block_index = uni->block_index; + int array_size = -1; + int array_stride = -1; + char *var_name = get_top_level_name(uni->name); + char *interface_name = + get_top_level_name(shProg->BufferInterfaceBlocks[block_index].Name); + + if (strcmp(var_name, interface_name) == 0) { + /* Deal with instanced array of SSBOs */ + char *temp_name = get_var_name(uni->name); + if (!temp_name) { + linker_error(shProg, "Out of memory during linking.\n"); + goto write_top_level_array_size_and_stride; + } + free(var_name); + var_name = get_top_level_name(temp_name); + free(temp_name); + if (!var_name) { + linker_error(shProg, "Out of memory during linking.\n"); + goto write_top_level_array_size_and_stride; + } + } + + for (unsigned i = 0; i < shProg->NumShaders; i++) { + if (shProg->Shaders[i] == NULL) + continue; + + const gl_shader *stage = shProg->Shaders[i]; + foreach_in_list(ir_instruction, node, stage->ir) { + ir_variable *var = node->as_variable(); + if (!var || !var->get_interface_type() || + var->data.mode != ir_var_shader_storage) + continue; + + const glsl_type *interface = var->get_interface_type(); + + if (strcmp(interface_name, interface->name) != 0) + continue; + + for (unsigned i = 0; i < interface->length; i++) { + const glsl_struct_field *field = &interface->fields.structure[i]; + if (strcmp(field->name, var_name) != 0) + continue; + + array_stride = get_array_stride(uni, interface, field, + interface_name, var_name); + array_size = get_array_size(uni, field, interface_name, var_name); + goto write_top_level_array_size_and_stride; + } + } + } +write_top_level_array_size_and_stride: + free(interface_name); + free(var_name); + uni->top_level_array_stride = array_stride; + uni->top_level_array_size = array_size; +} + +/** + * Builds up a list of program resources that point to existing + * resource data. + */ +void +build_program_resource_list(struct gl_shader_program *shProg) +{ + /* Rebuild resource list. */ + if (shProg->ProgramResourceList) { + ralloc_free(shProg->ProgramResourceList); + shProg->ProgramResourceList = NULL; + shProg->NumProgramResourceList = 0; + } + + int input_stage = MESA_SHADER_STAGES, output_stage = 0; + + /* Determine first input and final output stage. These are used to + * detect which variables should be enumerated in the resource list + * for GL_PROGRAM_INPUT and GL_PROGRAM_OUTPUT. + */ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (!shProg->_LinkedShaders[i]) + continue; + if (input_stage == MESA_SHADER_STAGES) + input_stage = i; + output_stage = i; + } + + /* Empty shader, no resources. */ + if (input_stage == MESA_SHADER_STAGES && output_stage == 0) + return; + + /* Program interface needs to expose varyings in case of SSO. */ + if (shProg->SeparateShader) { + if (!add_packed_varyings(shProg, input_stage, GL_PROGRAM_INPUT)) + return; + + if (!add_packed_varyings(shProg, output_stage, GL_PROGRAM_OUTPUT)) + return; + } + + if (!add_fragdata_arrays(shProg)) + return; + + /* Add inputs and outputs to the resource list. */ + if (!add_interface_variables(shProg, shProg->_LinkedShaders[input_stage]->ir, + GL_PROGRAM_INPUT)) + return; + + if (!add_interface_variables(shProg, shProg->_LinkedShaders[output_stage]->ir, + GL_PROGRAM_OUTPUT)) + return; + + /* Add transform feedback varyings. */ + if (shProg->LinkedTransformFeedback.NumVarying > 0) { + for (int i = 0; i < shProg->LinkedTransformFeedback.NumVarying; i++) { + if (!add_program_resource(shProg, GL_TRANSFORM_FEEDBACK_VARYING, + &shProg->LinkedTransformFeedback.Varyings[i], + 0)) + return; + } + } + + /* Add uniforms from uniform storage. */ + for (unsigned i = 0; i < shProg->NumUniformStorage; i++) { + /* Do not add uniforms internally used by Mesa. */ + if (shProg->UniformStorage[i].hidden) + continue; + + uint8_t stageref = + build_stageref(shProg, shProg->UniformStorage[i].name, + ir_var_uniform); + + /* Add stagereferences for uniforms in a uniform block. */ + int block_index = shProg->UniformStorage[i].block_index; + if (block_index != -1) { + for (unsigned j = 0; j < MESA_SHADER_STAGES; j++) { + if (shProg->InterfaceBlockStageIndex[j][block_index] != -1) + stageref |= (1 << j); + } + } + + bool is_shader_storage = shProg->UniformStorage[i].is_shader_storage; + GLenum type = is_shader_storage ? GL_BUFFER_VARIABLE : GL_UNIFORM; + if (!should_add_buffer_variable(shProg, type, + shProg->UniformStorage[i].name)) + continue; + + if (is_shader_storage) { + calculate_array_size_and_stride(shProg, &shProg->UniformStorage[i]); + } + + if (!add_program_resource(shProg, type, + &shProg->UniformStorage[i], stageref)) + return; + } + + /* Add program uniform blocks and shader storage blocks. */ + for (unsigned i = 0; i < shProg->NumBufferInterfaceBlocks; i++) { + bool is_shader_storage = shProg->BufferInterfaceBlocks[i].IsShaderStorage; + GLenum type = is_shader_storage ? GL_SHADER_STORAGE_BLOCK : GL_UNIFORM_BLOCK; + if (!add_program_resource(shProg, type, + &shProg->BufferInterfaceBlocks[i], 0)) + return; + } + + /* Add atomic counter buffers. */ + for (unsigned i = 0; i < shProg->NumAtomicBuffers; i++) { + if (!add_program_resource(shProg, GL_ATOMIC_COUNTER_BUFFER, + &shProg->AtomicBuffers[i], 0)) + return; + } + + for (unsigned i = 0; i < shProg->NumUniformStorage; i++) { + GLenum type; + if (!shProg->UniformStorage[i].hidden) + continue; + + for (int j = MESA_SHADER_VERTEX; j < MESA_SHADER_STAGES; j++) { + if (!shProg->UniformStorage[i].opaque[j].active || + !shProg->UniformStorage[i].type->is_subroutine()) + continue; + + type = _mesa_shader_stage_to_subroutine_uniform((gl_shader_stage)j); + /* add shader subroutines */ + if (!add_program_resource(shProg, type, &shProg->UniformStorage[i], 0)) + return; + } + } + + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + struct gl_shader *sh = shProg->_LinkedShaders[i]; + GLuint type; + + if (!sh) + continue; + + type = _mesa_shader_stage_to_subroutine((gl_shader_stage)i); + for (unsigned j = 0; j < sh->NumSubroutineFunctions; j++) { + if (!add_program_resource(shProg, type, &sh->SubroutineFunctions[j], 0)) + return; + } + } +} + +/** + * This check is done to make sure we allow only constant expression + * indexing and "constant-index-expression" (indexing with an expression + * that includes loop induction variable). + */ +static bool +validate_sampler_array_indexing(struct gl_context *ctx, + struct gl_shader_program *prog) +{ + dynamic_sampler_array_indexing_visitor v; + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + bool no_dynamic_indexing = + ctx->Const.ShaderCompilerOptions[i].EmitNoIndirectSampler; + + /* Search for array derefs in shader. */ + v.run(prog->_LinkedShaders[i]->ir); + if (v.uses_dynamic_sampler_array_indexing()) { + const char *msg = "sampler arrays indexed with non-constant " + "expressions is forbidden in GLSL %s %u"; + /* Backend has indicated that it has no dynamic indexing support. */ + if (no_dynamic_indexing) { + linker_error(prog, msg, prog->IsES ? "ES" : "", prog->Version); + return false; + } else { + linker_warning(prog, msg, prog->IsES ? "ES" : "", prog->Version); + } + } + } + return true; +} + +static void +link_assign_subroutine_types(struct gl_shader_program *prog) +{ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + gl_shader *sh = prog->_LinkedShaders[i]; + + if (sh == NULL) + continue; + + foreach_in_list(ir_instruction, node, sh->ir) { + ir_function *fn = node->as_function(); + if (!fn) + continue; + + if (fn->is_subroutine) + sh->NumSubroutineUniformTypes++; + + if (!fn->num_subroutine_types) + continue; + + sh->SubroutineFunctions = reralloc(sh, sh->SubroutineFunctions, + struct gl_subroutine_function, + sh->NumSubroutineFunctions + 1); + sh->SubroutineFunctions[sh->NumSubroutineFunctions].name = ralloc_strdup(sh, fn->name); + sh->SubroutineFunctions[sh->NumSubroutineFunctions].num_compat_types = fn->num_subroutine_types; + sh->SubroutineFunctions[sh->NumSubroutineFunctions].types = + ralloc_array(sh, const struct glsl_type *, + fn->num_subroutine_types); + + /* From Section 4.4.4(Subroutine Function Layout Qualifiers) of the + * GLSL 4.5 spec: + * + * "Each subroutine with an index qualifier in the shader must be + * given a unique index, otherwise a compile or link error will be + * generated." + */ + for (unsigned j = 0; j < sh->NumSubroutineFunctions; j++) { + if (sh->SubroutineFunctions[j].index != -1 && + sh->SubroutineFunctions[j].index == fn->subroutine_index) { + linker_error(prog, "each subroutine index qualifier in the " + "shader must be unique\n"); + return; + } + } + sh->SubroutineFunctions[sh->NumSubroutineFunctions].index = + fn->subroutine_index; + + for (int j = 0; j < fn->num_subroutine_types; j++) + sh->SubroutineFunctions[sh->NumSubroutineFunctions].types[j] = fn->subroutine_types[j]; + sh->NumSubroutineFunctions++; + } + + /* Assign index for subroutines without an explicit index*/ + int index = 0; + for (unsigned j = 0; j < sh->NumSubroutineFunctions; j++) { + while (sh->SubroutineFunctions[j].index == -1) { + for (unsigned k = 0; k < sh->NumSubroutineFunctions; k++) { + if (sh->SubroutineFunctions[k].index == index) + break; + else if (k == sh->NumSubroutineFunctions - 1) + sh->SubroutineFunctions[j].index = index; + } + index++; + } + } + } +} + +static void +split_ubos_and_ssbos(void *mem_ctx, + struct gl_uniform_block *blocks, + unsigned num_blocks, + struct gl_uniform_block ***ubos, + unsigned *num_ubos, + unsigned **ubo_interface_block_indices, + struct gl_uniform_block ***ssbos, + unsigned *num_ssbos, + unsigned **ssbo_interface_block_indices) +{ + unsigned num_ubo_blocks = 0; + unsigned num_ssbo_blocks = 0; + + for (unsigned i = 0; i < num_blocks; i++) { + if (blocks[i].IsShaderStorage) + num_ssbo_blocks++; + else + num_ubo_blocks++; + } + + *ubos = ralloc_array(mem_ctx, gl_uniform_block *, num_ubo_blocks); + *num_ubos = 0; + + *ssbos = ralloc_array(mem_ctx, gl_uniform_block *, num_ssbo_blocks); + *num_ssbos = 0; + + if (ubo_interface_block_indices) + *ubo_interface_block_indices = + ralloc_array(mem_ctx, unsigned, num_ubo_blocks); + + if (ssbo_interface_block_indices) + *ssbo_interface_block_indices = + ralloc_array(mem_ctx, unsigned, num_ssbo_blocks); + + for (unsigned i = 0; i < num_blocks; i++) { + if (blocks[i].IsShaderStorage) { + (*ssbos)[*num_ssbos] = &blocks[i]; + if (ssbo_interface_block_indices) + (*ssbo_interface_block_indices)[*num_ssbos] = i; + (*num_ssbos)++; + } else { + (*ubos)[*num_ubos] = &blocks[i]; + if (ubo_interface_block_indices) + (*ubo_interface_block_indices)[*num_ubos] = i; + (*num_ubos)++; + } + } + + assert(*num_ubos + *num_ssbos == num_blocks); +} + +static void +set_always_active_io(exec_list *ir, ir_variable_mode io_mode) +{ + assert(io_mode == ir_var_shader_in || io_mode == ir_var_shader_out); + + foreach_in_list(ir_instruction, node, ir) { + ir_variable *const var = node->as_variable(); + + if (var == NULL || var->data.mode != io_mode) + continue; + + /* Don't set always active on builtins that haven't been redeclared */ + if (var->data.how_declared == ir_var_declared_implicitly) + continue; + + var->data.always_active_io = true; + } +} + +/** + * When separate shader programs are enabled, only input/outputs between + * the stages of a multi-stage separate program can be safely removed + * from the shader interface. Other inputs/outputs must remain active. + */ +static void +disable_varying_optimizations_for_sso(struct gl_shader_program *prog) +{ + unsigned first, last; + assert(prog->SeparateShader); + + first = MESA_SHADER_STAGES; + last = 0; + + /* Determine first and last stage. Excluding the compute stage */ + for (unsigned i = 0; i < MESA_SHADER_COMPUTE; i++) { + if (!prog->_LinkedShaders[i]) + continue; + if (first == MESA_SHADER_STAGES) + first = i; + last = i; + } + + if (first == MESA_SHADER_STAGES) + return; + + for (unsigned stage = 0; stage < MESA_SHADER_STAGES; stage++) { + gl_shader *sh = prog->_LinkedShaders[stage]; + if (!sh) + continue; + + if (first == last) { + /* For a single shader program only allow inputs to the vertex shader + * and outputs from the fragment shader to be removed. + */ + if (stage != MESA_SHADER_VERTEX) + set_always_active_io(sh->ir, ir_var_shader_in); + if (stage != MESA_SHADER_FRAGMENT) + set_always_active_io(sh->ir, ir_var_shader_out); + } else { + /* For multi-stage separate shader programs only allow inputs and + * outputs between the shader stages to be removed as well as inputs + * to the vertex shader and outputs from the fragment shader. + */ + if (stage == first && stage != MESA_SHADER_VERTEX) + set_always_active_io(sh->ir, ir_var_shader_in); + else if (stage == last && stage != MESA_SHADER_FRAGMENT) + set_always_active_io(sh->ir, ir_var_shader_out); + } + } +} + +void +link_shaders(struct gl_context *ctx, struct gl_shader_program *prog) +{ + tfeedback_decl *tfeedback_decls = NULL; + unsigned num_tfeedback_decls = prog->TransformFeedback.NumVarying; + + void *mem_ctx = ralloc_context(NULL); // temporary linker context + + prog->LinkStatus = true; /* All error paths will set this to false */ + prog->Validated = false; + prog->_Used = false; + + prog->ARB_fragment_coord_conventions_enable = false; + + /* Separate the shaders into groups based on their type. + */ + struct gl_shader **shader_list[MESA_SHADER_STAGES]; + unsigned num_shaders[MESA_SHADER_STAGES]; + + for (int i = 0; i < MESA_SHADER_STAGES; i++) { + shader_list[i] = (struct gl_shader **) + calloc(prog->NumShaders, sizeof(struct gl_shader *)); + num_shaders[i] = 0; + } + + unsigned min_version = UINT_MAX; + unsigned max_version = 0; + const bool is_es_prog = + (prog->NumShaders > 0 && prog->Shaders[0]->IsES) ? true : false; + for (unsigned i = 0; i < prog->NumShaders; i++) { + min_version = MIN2(min_version, prog->Shaders[i]->Version); + max_version = MAX2(max_version, prog->Shaders[i]->Version); + + if (prog->Shaders[i]->IsES != is_es_prog) { + linker_error(prog, "all shaders must use same shading " + "language version\n"); + goto done; + } + + if (prog->Shaders[i]->ARB_fragment_coord_conventions_enable) { + prog->ARB_fragment_coord_conventions_enable = true; + } + + gl_shader_stage shader_type = prog->Shaders[i]->Stage; + shader_list[shader_type][num_shaders[shader_type]] = prog->Shaders[i]; + num_shaders[shader_type]++; + } + + /* In desktop GLSL, different shader versions may be linked together. In + * GLSL ES, all shader versions must be the same. + */ + if (is_es_prog && min_version != max_version) { + linker_error(prog, "all shaders must use same shading " + "language version\n"); + goto done; + } + + prog->Version = max_version; + prog->IsES = is_es_prog; + + /* From OpenGL 4.5 Core specification (7.3 Program Objects): + * "Linking can fail for a variety of reasons as specified in the OpenGL + * Shading Language Specification, as well as any of the following + * reasons: + * + * * No shader objects are attached to program. + * + * ..." + * + * Same rule applies for OpenGL ES >= 3.1. + */ + + if (prog->NumShaders == 0 && + ((ctx->API == API_OPENGL_CORE && ctx->Version >= 45) || + (ctx->API == API_OPENGLES2 && ctx->Version >= 31))) { + linker_error(prog, "No shader objects are attached to program.\n"); + goto done; + } + + /* Some shaders have to be linked with some other shaders present. + */ + if (num_shaders[MESA_SHADER_GEOMETRY] > 0 && + num_shaders[MESA_SHADER_VERTEX] == 0 && + !prog->SeparateShader) { + linker_error(prog, "Geometry shader must be linked with " + "vertex shader\n"); + goto done; + } + if (num_shaders[MESA_SHADER_TESS_EVAL] > 0 && + num_shaders[MESA_SHADER_VERTEX] == 0 && + !prog->SeparateShader) { + linker_error(prog, "Tessellation evaluation shader must be linked with " + "vertex shader\n"); + goto done; + } + if (num_shaders[MESA_SHADER_TESS_CTRL] > 0 && + num_shaders[MESA_SHADER_VERTEX] == 0 && + !prog->SeparateShader) { + linker_error(prog, "Tessellation control shader must be linked with " + "vertex shader\n"); + goto done; + } + + /* The spec is self-contradictory here. It allows linking without a tess + * eval shader, but that can only be used with transform feedback and + * rasterization disabled. However, transform feedback isn't allowed + * with GL_PATCHES, so it can't be used. + * + * More investigation showed that the idea of transform feedback after + * a tess control shader was dropped, because some hw vendors couldn't + * support tessellation without a tess eval shader, but the linker section + * wasn't updated to reflect that. + * + * All specifications (ARB_tessellation_shader, GL 4.0-4.5) have this + * spec bug. + * + * Do what's reasonable and always require a tess eval shader if a tess + * control shader is present. + */ + if (num_shaders[MESA_SHADER_TESS_CTRL] > 0 && + num_shaders[MESA_SHADER_TESS_EVAL] == 0 && + !prog->SeparateShader) { + linker_error(prog, "Tessellation control shader must be linked with " + "tessellation evaluation shader\n"); + goto done; + } + + /* Compute shaders have additional restrictions. */ + if (num_shaders[MESA_SHADER_COMPUTE] > 0 && + num_shaders[MESA_SHADER_COMPUTE] != prog->NumShaders) { + linker_error(prog, "Compute shaders may not be linked with any other " + "type of shader\n"); + } + + for (unsigned int i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] != NULL) + _mesa_delete_shader(ctx, prog->_LinkedShaders[i]); + + prog->_LinkedShaders[i] = NULL; + } + + /* Link all shaders for a particular stage and validate the result. + */ + for (int stage = 0; stage < MESA_SHADER_STAGES; stage++) { + if (num_shaders[stage] > 0) { + gl_shader *const sh = + link_intrastage_shaders(mem_ctx, ctx, prog, shader_list[stage], + num_shaders[stage]); + + if (!prog->LinkStatus) { + if (sh) + _mesa_delete_shader(ctx, sh); + goto done; + } + + switch (stage) { + case MESA_SHADER_VERTEX: + validate_vertex_shader_executable(prog, sh); + break; + case MESA_SHADER_TESS_CTRL: + /* nothing to be done */ + break; + case MESA_SHADER_TESS_EVAL: + validate_tess_eval_shader_executable(prog, sh); + break; + case MESA_SHADER_GEOMETRY: + validate_geometry_shader_executable(prog, sh); + break; + case MESA_SHADER_FRAGMENT: + validate_fragment_shader_executable(prog, sh); + break; + } + if (!prog->LinkStatus) { + if (sh) + _mesa_delete_shader(ctx, sh); + goto done; + } + + _mesa_reference_shader(ctx, &prog->_LinkedShaders[stage], sh); + } + } + + if (num_shaders[MESA_SHADER_GEOMETRY] > 0) + prog->LastClipDistanceArraySize = prog->Geom.ClipDistanceArraySize; + else if (num_shaders[MESA_SHADER_TESS_EVAL] > 0) + prog->LastClipDistanceArraySize = prog->TessEval.ClipDistanceArraySize; + else if (num_shaders[MESA_SHADER_VERTEX] > 0) + prog->LastClipDistanceArraySize = prog->Vert.ClipDistanceArraySize; + else + prog->LastClipDistanceArraySize = 0; /* Not used */ + + /* Here begins the inter-stage linking phase. Some initial validation is + * performed, then locations are assigned for uniforms, attributes, and + * varyings. + */ + cross_validate_uniforms(prog); + if (!prog->LinkStatus) + goto done; + + unsigned first, last, prev; + + first = MESA_SHADER_STAGES; + last = 0; + + /* Determine first and last stage. */ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (!prog->_LinkedShaders[i]) + continue; + if (first == MESA_SHADER_STAGES) + first = i; + last = i; + } + + check_explicit_uniform_locations(ctx, prog); + link_assign_subroutine_types(prog); + + if (!prog->LinkStatus) + goto done; + + resize_tes_inputs(ctx, prog); + + /* Validate the inputs of each stage with the output of the preceding + * stage. + */ + prev = first; + for (unsigned i = prev + 1; i <= MESA_SHADER_FRAGMENT; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + validate_interstage_inout_blocks(prog, prog->_LinkedShaders[prev], + prog->_LinkedShaders[i]); + if (!prog->LinkStatus) + goto done; + + cross_validate_outputs_to_inputs(prog, + prog->_LinkedShaders[prev], + prog->_LinkedShaders[i]); + if (!prog->LinkStatus) + goto done; + + prev = i; + } + + /* Cross-validate uniform blocks between shader stages */ + validate_interstage_uniform_blocks(prog, prog->_LinkedShaders, + MESA_SHADER_STAGES); + if (!prog->LinkStatus) + goto done; + + for (unsigned int i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] != NULL) + lower_named_interface_blocks(mem_ctx, prog->_LinkedShaders[i]); + } + + /* Implement the GLSL 1.30+ rule for discard vs infinite loops Do + * it before optimization because we want most of the checks to get + * dropped thanks to constant propagation. + * + * This rule also applies to GLSL ES 3.00. + */ + if (max_version >= (is_es_prog ? 300 : 130)) { + struct gl_shader *sh = prog->_LinkedShaders[MESA_SHADER_FRAGMENT]; + if (sh) { + lower_discard_flow(sh->ir); + } + } + + if (prog->SeparateShader) + disable_varying_optimizations_for_sso(prog); + + if (!interstage_cross_validate_uniform_blocks(prog)) + goto done; + + /* Do common optimization before assigning storage for attributes, + * uniforms, and varyings. Later optimization could possibly make + * some of that unused. + */ + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + detect_recursion_linked(prog, prog->_LinkedShaders[i]->ir); + if (!prog->LinkStatus) + goto done; + + if (ctx->Const.ShaderCompilerOptions[i].LowerClipDistance) { + lower_clip_distance(prog->_LinkedShaders[i]); + } + + if (ctx->Const.LowerTessLevel) { + lower_tess_level(prog->_LinkedShaders[i]); + } + + while (do_common_optimization(prog->_LinkedShaders[i]->ir, true, false, + &ctx->Const.ShaderCompilerOptions[i], + ctx->Const.NativeIntegers)) + ; + + lower_const_arrays_to_uniforms(prog->_LinkedShaders[i]->ir); + } + + /* Validation for special cases where we allow sampler array indexing + * with loop induction variable. This check emits a warning or error + * depending if backend can handle dynamic indexing. + */ + if ((!prog->IsES && prog->Version < 130) || + (prog->IsES && prog->Version < 300)) { + if (!validate_sampler_array_indexing(ctx, prog)) + goto done; + } + + /* Check and validate stream emissions in geometry shaders */ + validate_geometry_shader_emissions(ctx, prog); + + /* Mark all generic shader inputs and outputs as unpaired. */ + for (unsigned i = MESA_SHADER_VERTEX; i <= MESA_SHADER_FRAGMENT; i++) { + if (prog->_LinkedShaders[i] != NULL) { + link_invalidate_variable_locations(prog->_LinkedShaders[i]->ir); + } + } + + prev = first; + for (unsigned i = prev + 1; i <= MESA_SHADER_FRAGMENT; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + match_explicit_outputs_to_inputs(prog, prog->_LinkedShaders[prev], + prog->_LinkedShaders[i]); + prev = i; + } + + if (!assign_attribute_or_color_locations(prog, &ctx->Const, + MESA_SHADER_VERTEX)) { + goto done; + } + + if (!assign_attribute_or_color_locations(prog, &ctx->Const, + MESA_SHADER_FRAGMENT)) { + goto done; + } + + if (num_tfeedback_decls != 0) { + /* From GL_EXT_transform_feedback: + * A program will fail to link if: + * + * * the <count> specified by TransformFeedbackVaryingsEXT is + * non-zero, but the program object has no vertex or geometry + * shader; + */ + if (first == MESA_SHADER_FRAGMENT) { + linker_error(prog, "Transform feedback varyings specified, but " + "no vertex or geometry shader is present.\n"); + goto done; + } + + tfeedback_decls = ralloc_array(mem_ctx, tfeedback_decl, + prog->TransformFeedback.NumVarying); + if (!parse_tfeedback_decls(ctx, prog, mem_ctx, num_tfeedback_decls, + prog->TransformFeedback.VaryingNames, + tfeedback_decls)) + goto done; + } + + /* Linking the stages in the opposite order (from fragment to vertex) + * ensures that inter-shader outputs written to in an earlier stage are + * eliminated if they are (transitively) not used in a later stage. + */ + int next; + + if (first < MESA_SHADER_FRAGMENT) { + gl_shader *const sh = prog->_LinkedShaders[last]; + + if (first != MESA_SHADER_VERTEX) { + /* There was no vertex shader, but we still have to assign varying + * locations for use by tessellation/geometry shader inputs in SSO. + * + * If the shader is not separable (i.e., prog->SeparateShader is + * false), linking will have already failed when first is not + * MESA_SHADER_VERTEX. + */ + if (!assign_varying_locations(ctx, mem_ctx, prog, + NULL, prog->_LinkedShaders[first], + num_tfeedback_decls, tfeedback_decls)) + goto done; + } + + if (last != MESA_SHADER_FRAGMENT && + (num_tfeedback_decls != 0 || prog->SeparateShader)) { + /* There was no fragment shader, but we still have to assign varying + * locations for use by transform feedback. + */ + if (!assign_varying_locations(ctx, mem_ctx, prog, + sh, NULL, + num_tfeedback_decls, tfeedback_decls)) + goto done; + } + + do_dead_builtin_varyings(ctx, sh, NULL, + num_tfeedback_decls, tfeedback_decls); + + remove_unused_shader_inputs_and_outputs(prog->SeparateShader, sh, + ir_var_shader_out); + } + else if (first == MESA_SHADER_FRAGMENT) { + /* If the program only contains a fragment shader... + */ + gl_shader *const sh = prog->_LinkedShaders[first]; + + do_dead_builtin_varyings(ctx, NULL, sh, + num_tfeedback_decls, tfeedback_decls); + + if (prog->SeparateShader) { + if (!assign_varying_locations(ctx, mem_ctx, prog, + NULL /* producer */, + sh /* consumer */, + 0 /* num_tfeedback_decls */, + NULL /* tfeedback_decls */)) + goto done; + } else { + remove_unused_shader_inputs_and_outputs(false, sh, + ir_var_shader_in); + } + } + + next = last; + for (int i = next - 1; i >= 0; i--) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + gl_shader *const sh_i = prog->_LinkedShaders[i]; + gl_shader *const sh_next = prog->_LinkedShaders[next]; + + if (!assign_varying_locations(ctx, mem_ctx, prog, sh_i, sh_next, + next == MESA_SHADER_FRAGMENT ? num_tfeedback_decls : 0, + tfeedback_decls)) + goto done; + + do_dead_builtin_varyings(ctx, sh_i, sh_next, + next == MESA_SHADER_FRAGMENT ? num_tfeedback_decls : 0, + tfeedback_decls); + + /* This must be done after all dead varyings are eliminated. */ + if (!check_against_output_limit(ctx, prog, sh_i)) + goto done; + if (!check_against_input_limit(ctx, prog, sh_next)) + goto done; + + next = i; + } + + if (!store_tfeedback_info(ctx, prog, num_tfeedback_decls, tfeedback_decls)) + goto done; + + update_array_sizes(prog); + link_assign_uniform_locations(prog, ctx->Const.UniformBooleanTrue); + link_assign_atomic_counter_resources(ctx, prog); + store_fragdepth_layout(prog); + + link_calculate_subroutine_compat(prog); + check_resources(ctx, prog); + check_subroutine_resources(prog); + check_image_resources(ctx, prog); + link_check_atomic_counter_resources(ctx, prog); + + if (!prog->LinkStatus) + goto done; + + /* OpenGL ES requires that a vertex shader and a fragment shader both be + * present in a linked program. GL_ARB_ES2_compatibility doesn't say + * anything about shader linking when one of the shaders (vertex or + * fragment shader) is absent. So, the extension shouldn't change the + * behavior specified in GLSL specification. + */ + if (!prog->SeparateShader && ctx->API == API_OPENGLES2) { + /* With ES < 3.1 one needs to have always vertex + fragment shader. */ + if (ctx->Version < 31) { + if (prog->_LinkedShaders[MESA_SHADER_VERTEX] == NULL) { + linker_error(prog, "program lacks a vertex shader\n"); + } else if (prog->_LinkedShaders[MESA_SHADER_FRAGMENT] == NULL) { + linker_error(prog, "program lacks a fragment shader\n"); + } + } else { + /* From OpenGL ES 3.1 specification (7.3 Program Objects): + * "Linking can fail for a variety of reasons as specified in the + * OpenGL ES Shading Language Specification, as well as any of the + * following reasons: + * + * ... + * + * * program contains objects to form either a vertex shader or + * fragment shader, and program is not separable, and does not + * contain objects to form both a vertex shader and fragment + * shader." + */ + if (!!prog->_LinkedShaders[MESA_SHADER_VERTEX] ^ + !!prog->_LinkedShaders[MESA_SHADER_FRAGMENT]) { + linker_error(prog, "Program needs to contain both vertex and " + "fragment shaders.\n"); + } + } + } + + /* Split BufferInterfaceBlocks into UniformBlocks and ShaderStorageBlocks + * for gl_shader_program and gl_shader, so that drivers that need separate + * index spaces for each set can have that. + */ + for (unsigned i = MESA_SHADER_VERTEX; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] != NULL) { + gl_shader *sh = prog->_LinkedShaders[i]; + split_ubos_and_ssbos(sh, + sh->BufferInterfaceBlocks, + sh->NumBufferInterfaceBlocks, + &sh->UniformBlocks, + &sh->NumUniformBlocks, + NULL, + &sh->ShaderStorageBlocks, + &sh->NumShaderStorageBlocks, + NULL); + } + } + + split_ubos_and_ssbos(prog, + prog->BufferInterfaceBlocks, + prog->NumBufferInterfaceBlocks, + &prog->UniformBlocks, + &prog->NumUniformBlocks, + &prog->UboInterfaceBlockIndex, + &prog->ShaderStorageBlocks, + &prog->NumShaderStorageBlocks, + &prog->SsboInterfaceBlockIndex); + + /* FINISHME: Assign fragment shader output locations. */ + + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + if (prog->_LinkedShaders[i] == NULL) + continue; + + if (ctx->Const.ShaderCompilerOptions[i].LowerBufferInterfaceBlocks) + lower_ubo_reference(prog->_LinkedShaders[i]); + + if (ctx->Const.ShaderCompilerOptions[i].LowerShaderSharedVariables) + lower_shared_reference(prog->_LinkedShaders[i], + &prog->Comp.SharedSize); + + lower_vector_derefs(prog->_LinkedShaders[i]); + } + +done: + for (unsigned i = 0; i < MESA_SHADER_STAGES; i++) { + free(shader_list[i]); + if (prog->_LinkedShaders[i] == NULL) + continue; + + /* Do a final validation step to make sure that the IR wasn't + * invalidated by any modifications performed after intrastage linking. + */ + validate_ir_tree(prog->_LinkedShaders[i]->ir); + + /* Retain any live IR, but trash the rest. */ + reparent_ir(prog->_LinkedShaders[i]->ir, prog->_LinkedShaders[i]->ir); + + /* The symbol table in the linked shaders may contain references to + * variables that were removed (e.g., unused uniforms). Since it may + * contain junk, there is no possible valid use. Delete it and set the + * pointer to NULL. + */ + delete prog->_LinkedShaders[i]->symbols; + prog->_LinkedShaders[i]->symbols = NULL; + } + + ralloc_free(mem_ctx); +} |