| /* |
| * Copyright © 2013 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 link_interface_blocks.cpp |
| * Linker support for GLSL's interface blocks. |
| */ |
| |
| #include "ir.h" |
| #include "glsl_symbol_table.h" |
| #include "linker.h" |
| #include "main/macros.h" |
| #include "main/mtypes.h" |
| #include "util/hash_table.h" |
| #include "util/u_string.h" |
| |
| |
| namespace { |
| |
| /** |
| * Return true if interface members mismatch and its not allowed by GLSL. |
| */ |
| static bool |
| interstage_member_mismatch(struct gl_shader_program *prog, |
| const glsl_type *c, const glsl_type *p) { |
| |
| if (c->length != p->length) |
| return true; |
| |
| for (unsigned i = 0; i < c->length; i++) { |
| if (c->fields.structure[i].type != p->fields.structure[i].type) |
| return true; |
| if (strcmp(c->fields.structure[i].name, |
| p->fields.structure[i].name) != 0) |
| return true; |
| if (c->fields.structure[i].location != |
| p->fields.structure[i].location) |
| return true; |
| if (c->fields.structure[i].patch != |
| p->fields.structure[i].patch) |
| return true; |
| |
| /* From Section 4.5 (Interpolation Qualifiers) of the GLSL 4.40 spec: |
| * |
| * "It is a link-time error if, within the same stage, the |
| * interpolation qualifiers of variables of the same name do not |
| * match." |
| */ |
| if (prog->IsES || prog->data->Version < 440) |
| if (c->fields.structure[i].interpolation != |
| p->fields.structure[i].interpolation) |
| return true; |
| |
| /* From Section 4.3.4 (Input Variables) of the GLSL ES 3.0 spec: |
| * |
| * "The output of the vertex shader and the input of the fragment |
| * shader form an interface. For this interface, vertex shader |
| * output variables and fragment shader input variables of the same |
| * name must match in type and qualification (other than precision |
| * and out matching to in). |
| * |
| * The table in Section 9.2.1 Linked Shaders of the GLSL ES 3.1 spec |
| * says that centroid no longer needs to match for varyings. |
| * |
| * The table in Section 9.2.1 Linked Shaders of the GLSL ES 3.2 spec |
| * says that sample need not match for varyings. |
| */ |
| if (!prog->IsES || prog->data->Version < 310) |
| if (c->fields.structure[i].centroid != |
| p->fields.structure[i].centroid) |
| return true; |
| if (!prog->IsES) |
| if (c->fields.structure[i].sample != |
| p->fields.structure[i].sample) |
| return true; |
| } |
| |
| return false; |
| } |
| |
| /** |
| * Check if two interfaces match, according to intrastage interface matching |
| * rules. If they do, and the first interface uses an unsized array, it will |
| * be updated to reflect the array size declared in the second interface. |
| */ |
| bool |
| intrastage_match(ir_variable *a, |
| ir_variable *b, |
| struct gl_shader_program *prog, |
| bool match_precision) |
| { |
| /* Types must match. */ |
| if (a->get_interface_type() != b->get_interface_type()) { |
| /* Exception: if both the interface blocks are implicitly declared, |
| * don't force their types to match. They might mismatch due to the two |
| * shaders using different GLSL versions, and that's ok. |
| */ |
| if ((a->data.how_declared != ir_var_declared_implicitly || |
| b->data.how_declared != ir_var_declared_implicitly) && |
| (!prog->IsES || |
| interstage_member_mismatch(prog, a->get_interface_type(), |
| b->get_interface_type()))) |
| return false; |
| } |
| |
| /* Presence/absence of interface names must match. */ |
| if (a->is_interface_instance() != b->is_interface_instance()) |
| return false; |
| |
| /* For uniforms, instance names need not match. For shader ins/outs, |
| * it's not clear from the spec whether they need to match, but |
| * Mesa's implementation relies on them matching. |
| */ |
| if (a->is_interface_instance() && b->data.mode != ir_var_uniform && |
| b->data.mode != ir_var_shader_storage && |
| strcmp(a->name, b->name) != 0) { |
| return false; |
| } |
| |
| bool type_match = (match_precision ? |
| a->type == b->type : |
| a->type->compare_no_precision(b->type)); |
| |
| /* If a block is an array then it must match across the shader. |
| * Unsized arrays are also processed and matched agaist sized arrays. |
| */ |
| if (!type_match && (b->type->is_array() || a->type->is_array()) && |
| (b->is_interface_instance() || a->is_interface_instance()) && |
| !validate_intrastage_arrays(prog, b, a, match_precision)) |
| return false; |
| |
| return true; |
| } |
| |
| /** |
| * Check if two interfaces match, according to interstage (in/out) interface |
| * matching rules. |
| * |
| * If \c extra_array_level is true, the consumer interface is required to be |
| * an array and the producer interface is required to be a non-array. |
| * This is used for tessellation control and geometry shader consumers. |
| */ |
| static bool |
| interstage_match(struct gl_shader_program *prog, ir_variable *producer, |
| ir_variable *consumer, bool extra_array_level) |
| { |
| /* Types must match. */ |
| if (consumer->get_interface_type() != producer->get_interface_type()) { |
| /* Exception: if both the interface blocks are implicitly declared, |
| * don't force their types to match. They might mismatch due to the two |
| * shaders using different GLSL versions, and that's ok. |
| * |
| * Also we store some member information such as interpolation in |
| * glsl_type that doesn't always have to match across shader stages. |
| * Therefore we make a pass over the members glsl_struct_field to make |
| * sure we don't reject shaders where fields don't need to match. |
| */ |
| if ((consumer->data.how_declared != ir_var_declared_implicitly || |
| producer->data.how_declared != ir_var_declared_implicitly) && |
| interstage_member_mismatch(prog, consumer->get_interface_type(), |
| producer->get_interface_type())) |
| return false; |
| } |
| |
| /* Ignore outermost array if geom shader */ |
| const glsl_type *consumer_instance_type; |
| if (extra_array_level) { |
| consumer_instance_type = consumer->type->fields.array; |
| } else { |
| consumer_instance_type = consumer->type; |
| } |
| |
| /* If a block is an array then it must match across shaders. |
| * Since unsized arrays have been ruled out, we can check this by just |
| * making sure the types are equal. |
| */ |
| if ((consumer->is_interface_instance() && |
| consumer_instance_type->is_array()) || |
| (producer->is_interface_instance() && |
| producer->type->is_array())) { |
| if (consumer_instance_type != producer->type) |
| return false; |
| } |
| |
| return true; |
| } |
| |
| |
| /** |
| * This class keeps track of a mapping from an interface block name to the |
| * necessary information about that interface block to determine whether to |
| * generate a link error. |
| * |
| * Note: this class is expected to be short lived, so it doesn't make copies |
| * of the strings it references; it simply borrows the pointers from the |
| * ir_variable class. |
| */ |
| class interface_block_definitions |
| { |
| public: |
| interface_block_definitions() |
| : mem_ctx(ralloc_context(NULL)), |
| ht(_mesa_hash_table_create(NULL, _mesa_hash_string, |
| _mesa_key_string_equal)) |
| { |
| } |
| |
| ~interface_block_definitions() |
| { |
| ralloc_free(mem_ctx); |
| _mesa_hash_table_destroy(ht, NULL); |
| } |
| |
| /** |
| * Lookup the interface definition. Return NULL if none is found. |
| */ |
| ir_variable *lookup(ir_variable *var) |
| { |
| if (var->data.explicit_location && |
| var->data.location >= VARYING_SLOT_VAR0) { |
| char location_str[11]; |
| snprintf(location_str, 11, "%d", var->data.location); |
| |
| const struct hash_entry *entry = |
| _mesa_hash_table_search(ht, location_str); |
| return entry ? (ir_variable *) entry->data : NULL; |
| } else { |
| const struct hash_entry *entry = |
| _mesa_hash_table_search(ht, |
| var->get_interface_type()->without_array()->name); |
| return entry ? (ir_variable *) entry->data : NULL; |
| } |
| } |
| |
| /** |
| * Add a new interface definition. |
| */ |
| void store(ir_variable *var) |
| { |
| if (var->data.explicit_location && |
| var->data.location >= VARYING_SLOT_VAR0) { |
| /* If explicit location is given then lookup the variable by location. |
| * We turn the location into a string and use this as the hash key |
| * rather than the name. Note: We allocate enough space for a 32-bit |
| * unsigned location value which is overkill but future proof. |
| */ |
| char location_str[11]; |
| snprintf(location_str, 11, "%d", var->data.location); |
| _mesa_hash_table_insert(ht, ralloc_strdup(mem_ctx, location_str), var); |
| } else { |
| _mesa_hash_table_insert(ht, |
| var->get_interface_type()->without_array()->name, var); |
| } |
| } |
| |
| private: |
| /** |
| * Ralloc context for data structures allocated by this class. |
| */ |
| void *mem_ctx; |
| |
| /** |
| * Hash table mapping interface block name to an \c |
| * ir_variable. |
| */ |
| hash_table *ht; |
| }; |
| |
| |
| }; /* anonymous namespace */ |
| |
| |
| void |
| validate_intrastage_interface_blocks(struct gl_shader_program *prog, |
| const gl_shader **shader_list, |
| unsigned num_shaders) |
| { |
| interface_block_definitions in_interfaces; |
| interface_block_definitions out_interfaces; |
| interface_block_definitions uniform_interfaces; |
| interface_block_definitions buffer_interfaces; |
| |
| for (unsigned int i = 0; i < num_shaders; i++) { |
| if (shader_list[i] == NULL) |
| continue; |
| |
| foreach_in_list(ir_instruction, node, shader_list[i]->ir) { |
| ir_variable *var = node->as_variable(); |
| if (!var) |
| continue; |
| |
| const glsl_type *iface_type = var->get_interface_type(); |
| |
| if (iface_type == NULL) |
| continue; |
| |
| interface_block_definitions *definitions; |
| switch (var->data.mode) { |
| case ir_var_shader_in: |
| definitions = &in_interfaces; |
| break; |
| case ir_var_shader_out: |
| definitions = &out_interfaces; |
| break; |
| case ir_var_uniform: |
| definitions = &uniform_interfaces; |
| break; |
| case ir_var_shader_storage: |
| definitions = &buffer_interfaces; |
| break; |
| default: |
| /* Only in, out, and uniform interfaces are legal, so we should |
| * never get here. |
| */ |
| assert(!"illegal interface type"); |
| continue; |
| } |
| |
| ir_variable *prev_def = definitions->lookup(var); |
| if (prev_def == NULL) { |
| /* This is the first time we've seen the interface, so save |
| * it into the appropriate data structure. |
| */ |
| definitions->store(var); |
| } else if (!intrastage_match(prev_def, var, prog, |
| true /* match_precision */)) { |
| linker_error(prog, "definitions of interface block `%s' do not" |
| " match\n", iface_type->name); |
| return; |
| } |
| } |
| } |
| } |
| |
| static bool |
| is_builtin_gl_in_block(ir_variable *var, int consumer_stage) |
| { |
| return !strcmp(var->name, "gl_in") && |
| (consumer_stage == MESA_SHADER_TESS_CTRL || |
| consumer_stage == MESA_SHADER_TESS_EVAL || |
| consumer_stage == MESA_SHADER_GEOMETRY); |
| } |
| |
| void |
| validate_interstage_inout_blocks(struct gl_shader_program *prog, |
| const gl_linked_shader *producer, |
| const gl_linked_shader *consumer) |
| { |
| interface_block_definitions definitions; |
| /* VS -> GS, VS -> TCS, VS -> TES, TES -> GS */ |
| const bool extra_array_level = (producer->Stage == MESA_SHADER_VERTEX && |
| consumer->Stage != MESA_SHADER_FRAGMENT) || |
| consumer->Stage == MESA_SHADER_GEOMETRY; |
| |
| /* Check that block re-declarations of gl_PerVertex are compatible |
| * across shaders: From OpenGL Shading Language 4.5, section |
| * "7.1 Built-In Language Variables", page 130 of the PDF: |
| * |
| * "If multiple shaders using members of a built-in block belonging |
| * to the same interface are linked together in the same program, |
| * they must all redeclare the built-in block in the same way, as |
| * described in section 4.3.9 “Interface Blocks” for interface-block |
| * matching, or a link-time error will result." |
| * |
| * This is done explicitly outside of iterating the member variable |
| * declarations because it is possible that the variables are not used and |
| * so they would have been optimised out. |
| */ |
| const glsl_type *consumer_iface = |
| consumer->symbols->get_interface("gl_PerVertex", |
| ir_var_shader_in); |
| |
| const glsl_type *producer_iface = |
| producer->symbols->get_interface("gl_PerVertex", |
| ir_var_shader_out); |
| |
| if (producer_iface && consumer_iface && |
| interstage_member_mismatch(prog, consumer_iface, producer_iface)) { |
| linker_error(prog, "Incompatible or missing gl_PerVertex re-declaration " |
| "in consecutive shaders"); |
| return; |
| } |
| |
| /* Desktop OpenGL requires redeclaration of the built-in interfaces for |
| * SSO programs. Passes above implement following rules: |
| * |
| * From Section 7.4 (Program Pipeline Objects) of the OpenGL 4.6 Core |
| * spec: |
| * |
| * "To use any built-in input or output in the gl_PerVertex and |
| * gl_PerFragment blocks in separable program objects, shader code |
| * must redeclare those blocks prior to use. A separable program |
| * will fail to link if: |
| * |
| * it contains multiple shaders of a single type with different |
| * redeclarations of these built-in input and output blocks; or |
| * |
| * any shader uses a built-in block member not found in the |
| * redeclaration of that block." |
| * |
| * ARB_separate_shader_objects issues section (issue #28) states that |
| * redeclaration is not required for GLSL shaders using #version 140 or |
| * earlier (since interface blocks are not possible with older versions). |
| * |
| * From Section 7.4.1 (Shader Interface Matching) of the OpenGL ES 3.1 |
| * spec: |
| * |
| * "Built-in inputs or outputs do not affect interface matching." |
| * |
| * GL_OES_shader_io_blocks adds following: |
| * |
| * "When using any built-in input or output in the gl_PerVertex block |
| * in separable program objects, shader code may redeclare that block |
| * prior to use. If the shader does not redeclare the block, the |
| * intrinsically declared definition of that block will be used." |
| */ |
| |
| /* Add output interfaces from the producer to the symbol table. */ |
| foreach_in_list(ir_instruction, node, producer->ir) { |
| ir_variable *var = node->as_variable(); |
| if (!var || !var->get_interface_type() || var->data.mode != ir_var_shader_out) |
| continue; |
| |
| /* Built-in interface redeclaration check. */ |
| if (prog->SeparateShader && !prog->IsES && prog->data->Version >= 150 && |
| var->data.how_declared == ir_var_declared_implicitly && |
| var->data.used && !producer_iface) { |
| linker_error(prog, "missing output builtin block %s redeclaration " |
| "in separable shader program", |
| var->get_interface_type()->name); |
| return; |
| } |
| |
| definitions.store(var); |
| } |
| |
| /* Verify that the consumer's input interfaces match. */ |
| foreach_in_list(ir_instruction, node, consumer->ir) { |
| ir_variable *var = node->as_variable(); |
| if (!var || !var->get_interface_type() || var->data.mode != ir_var_shader_in) |
| continue; |
| |
| ir_variable *producer_def = definitions.lookup(var); |
| |
| /* Built-in interface redeclaration check. */ |
| if (prog->SeparateShader && !prog->IsES && prog->data->Version >= 150 && |
| var->data.how_declared == ir_var_declared_implicitly && |
| var->data.used && !producer_iface) { |
| linker_error(prog, "missing input builtin block %s redeclaration " |
| "in separable shader program", |
| var->get_interface_type()->name); |
| return; |
| } |
| |
| /* The producer doesn't generate this input: fail to link. Skip built-in |
| * 'gl_in[]' since that may not be present if the producer does not |
| * write to any of the pre-defined outputs (e.g. if the vertex shader |
| * does not write to gl_Position, etc), which is allowed and results in |
| * undefined behavior. |
| * |
| * From Section 4.3.4 (Inputs) of the GLSL 1.50 spec: |
| * |
| * "Only the input variables that are actually read need to be written |
| * by the previous stage; it is allowed to have superfluous |
| * declarations of input variables." |
| */ |
| if (producer_def == NULL && |
| !is_builtin_gl_in_block(var, consumer->Stage) && var->data.used) { |
| linker_error(prog, "Input block `%s' is not an output of " |
| "the previous stage\n", var->get_interface_type()->name); |
| return; |
| } |
| |
| if (producer_def && |
| !interstage_match(prog, producer_def, var, extra_array_level)) { |
| linker_error(prog, "definitions of interface block `%s' do not " |
| "match\n", var->get_interface_type()->name); |
| return; |
| } |
| } |
| } |
| |
| |
| void |
| validate_interstage_uniform_blocks(struct gl_shader_program *prog, |
| gl_linked_shader **stages) |
| { |
| interface_block_definitions definitions; |
| |
| for (int i = 0; i < MESA_SHADER_STAGES; i++) { |
| if (stages[i] == NULL) |
| continue; |
| |
| const gl_linked_shader *stage = stages[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_uniform && |
| var->data.mode != ir_var_shader_storage)) |
| continue; |
| |
| ir_variable *old_def = definitions.lookup(var); |
| if (old_def == NULL) { |
| definitions.store(var); |
| } else { |
| /* Interstage uniform matching rules are the same as intrastage |
| * uniform matchin rules (for uniforms, it is as though all |
| * shaders are in the same shader stage). |
| */ |
| if (!intrastage_match(old_def, var, prog, false /* precision */)) { |
| linker_error(prog, "definitions of uniform block `%s' do not " |
| "match\n", var->get_interface_type()->name); |
| return; |
| } |
| } |
| } |
| } |
| } |
