src/glsl/link_uniform_block_active_visitor.cpp

   1 /*
   2  * Copyright © 2013 Intel Corporation
   3  *
   4  * Permission is hereby granted, free of charge, to any person obtaining a
   5  * copy of this software and associated documentation files (the "Software"),
   6  * to deal in the Software without restriction, including without limitation
   7  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
   8  * and/or sell copies of the Software, and to permit persons to whom the
   9  * Software is furnished to do so, subject to the following conditions:
  10  *
  11  * The above copyright notice and this permission notice (including the next
  12  * paragraph) shall be included in all copies or substantial portions of the
  13  * Software.
  14  *
  15  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  16  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  17  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  18  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  19  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
  20  * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
  21  * DEALINGS IN THE SOFTWARE.
  22  */
  23
  24 #include "link_uniform_block_active_visitor.h"
  25 #include "program.h"
  26
  27 link_uniform_block_active *
  28 process_block(void *mem_ctx, struct hash_table *ht, ir_variable *var)
  29 {
  30    const hash_entry *const existing_block =
  31       _mesa_hash_table_search(ht, var->get_interface_type()->name);
  32
  33    const glsl_type *const block_type = var->is_interface_instance()
  34       ? var->type : var->get_interface_type();
  35
  36
  37    /* If a block with this block-name has not previously been seen, add it.
  38     * If a block with this block-name has been seen, it must be identical to
  39     * the block currently being examined.
  40     */
  41    if (existing_block == NULL) {
  42       link_uniform_block_active *const b =
  43          rzalloc(mem_ctx, struct link_uniform_block_active);
  44
  45       b->type = block_type;
  46       b->has_instance_name = var->is_interface_instance();
  47       b->is_shader_storage = var->data.mode == ir_var_shader_storage;
  48
  49       if (var->data.explicit_binding) {
  50          b->has_binding = true;
  51          b->binding = var->data.binding;
  52       } else {
  53          b->has_binding = false;
  54          b->binding = 0;
  55       }
  56
  57       if (var->data.vk_set) {
  58          b->set = var->data.set;
  59          b->index = var->data.index;
  60       }
  61
  62       _mesa_hash_table_insert(ht, var->get_interface_type()->name, (void *) b);
  63       return b;
  64    } else {
  65       link_uniform_block_active *const b =
  66          (link_uniform_block_active *) existing_block->data;
  67
  68       if (b->type != block_type
  69           || b->has_instance_name != var->is_interface_instance())
  70          return NULL;
  71       else
  72          return b;
  73    }
  74
  75    assert(!"Should not get here.");
  76    return NULL;
  77 }
  78
  79 ir_visitor_status
  80 link_uniform_block_active_visitor::visit(ir_variable *var)
  81 {
  82    if (!var->is_in_buffer_block())
  83       return visit_continue;
  84
  85    const glsl_type *const block_type = var->is_interface_instance()
  86       ? var->type : var->get_interface_type();
  87
  88    /* Section 2.11.6 (Uniform Variables) of the OpenGL ES 3.0.3 spec says:
  89     *
  90     *     "All members of a named uniform block declared with a shared or
  91     *     std140 layout qualifier are considered active, even if they are not
  92     *     referenced in any shader in the program. The uniform block itself is
  93     *     also considered active, even if no member of the block is
  94     *     referenced."
  95     */
  96    if (block_type->interface_packing == GLSL_INTERFACE_PACKING_PACKED)
  97       return visit_continue;
  98
  99    /* Process the block.  Bail if there was an error.
 100     */
 101    link_uniform_block_active *const b =
 102       process_block(this->mem_ctx, this->ht, var);
 103    if (b == NULL) {
 104       linker_error(this->prog,
 105                    "uniform block `%s' has mismatching definitions",
 106                    var->get_interface_type()->name);
 107       this->success = false;
 108       return visit_stop;
 109    }
 110
 111    assert(b->num_array_elements == 0);
 112    assert(b->array_elements == NULL);
 113    assert(b->type != NULL);
 114
 115    return visit_continue;
 116 }
 117
 118 ir_visitor_status
 119 link_uniform_block_active_visitor::visit_enter(ir_dereference_array *ir)
 120 {
 121    ir_dereference_variable *const d = ir->array->as_dereference_variable();
 122    ir_variable *const var = (d == NULL) ? NULL : d->var;
 123
 124    /* If the r-value being dereferenced is not a variable (e.g., a field of a
 125     * structure) or is not a uniform block instance, continue.
 126     *
 127     * WARNING: It is not enough for the variable to be part of uniform block.
 128     * It must represent the entire block.  Arrays (or matrices) inside blocks
 129     * that lack an instance name are handled by the ir_dereference_variable
 130     * function.
 131     */
 132    if (var == NULL
 133        || !var->is_in_buffer_block()
 134        || !var->is_interface_instance())
 135       return visit_continue;
 136
 137    /* Process the block.  Bail if there was an error.
 138     */
 139    link_uniform_block_active *const b =
 140       process_block(this->mem_ctx, this->ht, var);
 141    if (b == NULL) {
 142       linker_error(prog,
 143                    "uniform block `%s' has mismatching definitions",
 144                    var->get_interface_type()->name);
 145       this->success = false;
 146       return visit_stop;
 147    }
 148
 149    /* Block arrays must be declared with an instance name.
 150     */
 151    assert(b->has_instance_name);
 152    assert((b->num_array_elements == 0) == (b->array_elements == NULL));
 153    assert(b->type != NULL);
 154
 155    ir_constant *c = ir->array_index->as_constant();
 156
 157    if (c) {
 158       /* Index is a constant, so mark just that element used, if not already */
 159       const unsigned idx = c->get_uint_component(0);
 160
 161       unsigned i;
 162       for (i = 0; i < b->num_array_elements; i++) {
 163          if (b->array_elements[i] == idx)
 164             break;
 165       }
 166
 167       assert(i <= b->num_array_elements);
 168
 169       if (i == b->num_array_elements) {
 170          b->array_elements = reralloc(this->mem_ctx,
 171                                       b->array_elements,
 172                                       unsigned,
 173                                       b->num_array_elements + 1);
 174
 175          b->array_elements[b->num_array_elements] = idx;
 176
 177          b->num_array_elements++;
 178       }
 179    } else {
 180       /* The array index is not a constant, so mark the entire array used. */
 181       assert(b->type->is_array());
 182       if (b->num_array_elements < b->type->length) {
 183          b->num_array_elements = b->type->length;
 184          b->array_elements = reralloc(this->mem_ctx,
 185                                       b->array_elements,
 186                                       unsigned,
 187                                       b->num_array_elements);
 188
 189          for (unsigned i = 0; i < b->num_array_elements; i++) {
 190             b->array_elements[i] = i;
 191          }
 192       }
 193    }
 194
 195    return visit_continue_with_parent;
 196 }
 197
 198 ir_visitor_status
 199 link_uniform_block_active_visitor::visit(ir_dereference_variable *ir)
 200 {
 201    ir_variable *var = ir->var;
 202
 203    if (!var->is_in_buffer_block())
 204       return visit_continue;
 205
 206    assert(!var->is_interface_instance() || !var->type->is_array());
 207
 208    /* Process the block.  Bail if there was an error.
 209     */
 210    link_uniform_block_active *const b =
 211       process_block(this->mem_ctx, this->ht, var);
 212    if (b == NULL) {
 213       linker_error(this->prog,
 214                    "uniform block `%s' has mismatching definitions",
 215                    var->get_interface_type()->name);
 216       this->success = false;
 217       return visit_stop;
 218    }
 219
 220    assert(b->num_array_elements == 0);
 221    assert(b->array_elements == NULL);
 222    assert(b->type != NULL);
 223
 224    return visit_continue;
 225 }