glsl: move to compiler/

Signed-off-by: Emil Velikov <emil.velikov@collabora.com>
Acked-by: Matt Turner <mattst88@gmail.com>
Acked-by: Jose Fonseca <jfonseca@vmware.com>

1 files changed, 296 insertions, 0 deletions

diff --git a/src/compiler/glsl/link_uniform_block_active_visitor.cpp b/src/compiler/glsl/link_uniform_block_active_visitor.cpp
new file mode 100644
index 0000000..54fea70
--- /dev/null
+++ b/src/compiler/glsl/link_uniform_block_active_visitor.cpp
@@ -0,0 +1,296 @@
+/*
+ * 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.
+ */
+
+#include "link_uniform_block_active_visitor.h"
+#include "program.h"
+
+static link_uniform_block_active *
+process_block(void *mem_ctx, struct hash_table *ht, ir_variable *var)
+{
+   const hash_entry *const existing_block =
+      _mesa_hash_table_search(ht, var->get_interface_type()->name);
+
+   const glsl_type *const block_type = var->is_interface_instance()
+      ? var->type : var->get_interface_type();
+
+
+   /* If a block with this block-name has not previously been seen, add it.
+    * If a block with this block-name has been seen, it must be identical to
+    * the block currently being examined.
+    */
+   if (existing_block == NULL) {
+      link_uniform_block_active *const b =
+	 rzalloc(mem_ctx, struct link_uniform_block_active);
+
+      b->type = block_type;
+      b->has_instance_name = var->is_interface_instance();
+      b->is_shader_storage = var->data.mode == ir_var_shader_storage;
+
+      if (var->data.explicit_binding) {
+         b->has_binding = true;
+         b->binding = var->data.binding;
+      } else {
+         b->has_binding = false;
+         b->binding = 0;
+      }
+
+      _mesa_hash_table_insert(ht, var->get_interface_type()->name, (void *) b);
+      return b;
+   } else {
+      link_uniform_block_active *const b =
+	 (link_uniform_block_active *) existing_block->data;
+
+      if (b->type != block_type
+	  || b->has_instance_name != var->is_interface_instance())
+	 return NULL;
+      else
+	 return b;
+   }
+
+   assert(!"Should not get here.");
+   return NULL;
+}
+
+/* For arrays of arrays this function will give us a middle ground between
+ * detecting inactive uniform blocks and structuring them in a way that makes
+ * it easy to calculate the offset for indirect indexing.
+ *
+ * For example given the shader:
+ *
+ *   uniform ArraysOfArraysBlock
+ *   {
+ *      vec4 a;
+ *   } i[3][4][5];
+ *
+ *   void main()
+ *   {
+ *      vec4 b = i[0][1][1].a;
+ *      gl_Position = i[2][2][3].a + b;
+ *   }
+ *
+ * There are only 2 active blocks above but for the sake of indirect indexing
+ * and not over complicating the code we will end up with a count of 8.
+ * Here each dimension has 2 different indices counted so we end up with 2*2*2
+ */
+static struct uniform_block_array_elements **
+process_arrays(void *mem_ctx, ir_dereference_array *ir,
+               struct link_uniform_block_active *block)
+{
+   if (ir) {
+      struct uniform_block_array_elements **ub_array_ptr =
+         process_arrays(mem_ctx, ir->array->as_dereference_array(), block);
+      if (*ub_array_ptr == NULL) {
+         *ub_array_ptr = rzalloc(mem_ctx, struct uniform_block_array_elements);
+         (*ub_array_ptr)->ir = ir;
+      }
+
+      struct uniform_block_array_elements *ub_array = *ub_array_ptr;
+      ir_constant *c = ir->array_index->as_constant();
+      if (c) {
+         /* Index is a constant, so mark just that element used,
+          * if not already.
+          */
+         const unsigned idx = c->get_uint_component(0);
+
+         unsigned i;
+         for (i = 0; i < ub_array->num_array_elements; i++) {
+            if (ub_array->array_elements[i] == idx)
+               break;
+         }
+
+         assert(i <= ub_array->num_array_elements);
+
+         if (i == ub_array->num_array_elements) {
+            ub_array->array_elements = reralloc(mem_ctx,
+                                                ub_array->array_elements,
+                                                unsigned,
+                                                ub_array->num_array_elements + 1);
+
+            ub_array->array_elements[ub_array->num_array_elements] = idx;
+
+            ub_array->num_array_elements++;
+         }
+      } else {
+         /* The array index is not a constant,
+          * so mark the entire array used.
+          */
+         assert(ir->array->type->is_array());
+         if (ub_array->num_array_elements < ir->array->type->length) {
+            ub_array->num_array_elements = ir->array->type->length;
+            ub_array->array_elements = reralloc(mem_ctx,
+                                                ub_array->array_elements,
+                                                unsigned,
+                                                ub_array->num_array_elements);
+
+            for (unsigned i = 0; i < ub_array->num_array_elements; i++) {
+               ub_array->array_elements[i] = i;
+            }
+         }
+      }
+      return &ub_array->array;
+   } else {
+      return &block->array;
+   }
+}
+
+ir_visitor_status
+link_uniform_block_active_visitor::visit(ir_variable *var)
+{
+   if (!var->is_in_buffer_block())
+      return visit_continue;
+
+   /* Section 2.11.6 (Uniform Variables) of the OpenGL ES 3.0.3 spec says:
+    *
+    *     "All members of a named uniform block declared with a shared or
+    *     std140 layout qualifier are considered active, even if they are not
+    *     referenced in any shader in the program. The uniform block itself is
+    *     also considered active, even if no member of the block is
+    *     referenced."
+    */
+   if (var->get_interface_type()->interface_packing ==
+       GLSL_INTERFACE_PACKING_PACKED)
+      return visit_continue;
+
+   /* Process the block.  Bail if there was an error.
+    */
+   link_uniform_block_active *const b =
+      process_block(this->mem_ctx, this->ht, var);
+   if (b == NULL) {
+      linker_error(this->prog,
+                   "uniform block `%s' has mismatching definitions",
+                   var->get_interface_type()->name);
+      this->success = false;
+      return visit_stop;
+   }
+
+   assert(b->array == NULL);
+   assert(b->type != NULL);
+   assert(!b->type->is_array() || b->has_instance_name);
+
+   /* For uniform block arrays declared with a shared or std140 layout
+    * qualifier, mark all its instances as used.
+    */
+   const glsl_type *type = b->type;
+   struct uniform_block_array_elements **ub_array = &b->array;
+   while (type->is_array()) {
+      assert(b->type->length > 0);
+
+      *ub_array = rzalloc(this->mem_ctx, struct uniform_block_array_elements);
+      (*ub_array)->num_array_elements = type->length;
+      (*ub_array)->array_elements = reralloc(this->mem_ctx,
+                                             (*ub_array)->array_elements,
+                                             unsigned,
+                                             (*ub_array)->num_array_elements);
+
+      for (unsigned i = 0; i < (*ub_array)->num_array_elements; i++) {
+         (*ub_array)->array_elements[i] = i;
+      }
+      ub_array = &(*ub_array)->array;
+      type = type->fields.array;
+   }
+
+   return visit_continue;
+}
+
+ir_visitor_status
+link_uniform_block_active_visitor::visit_enter(ir_dereference_array *ir)
+{
+   /* cycle through arrays of arrays */
+   ir_dereference_array *base_ir = ir;
+   while (base_ir->array->ir_type == ir_type_dereference_array)
+      base_ir = base_ir->array->as_dereference_array();
+
+   ir_dereference_variable *const d =
+      base_ir->array->as_dereference_variable();
+   ir_variable *const var = (d == NULL) ? NULL : d->var;
+
+   /* If the r-value being dereferenced is not a variable (e.g., a field of a
+    * structure) or is not a uniform block instance, continue.
+    *
+    * WARNING: It is not enough for the variable to be part of uniform block.
+    * It must represent the entire block.  Arrays (or matrices) inside blocks
+    * that lack an instance name are handled by the ir_dereference_variable
+    * function.
+    */
+   if (var == NULL
+       || !var->is_in_buffer_block()
+       || !var->is_interface_instance())
+      return visit_continue;
+
+   /* Process the block.  Bail if there was an error.
+    */
+   link_uniform_block_active *const b =
+      process_block(this->mem_ctx, this->ht, var);
+   if (b == NULL) {
+      linker_error(prog,
+		   "uniform block `%s' has mismatching definitions",
+		   var->get_interface_type()->name);
+      this->success = false;
+      return visit_stop;
+   }
+
+   /* Block arrays must be declared with an instance name.
+    */
+   assert(b->has_instance_name);
+   assert(b->type != NULL);
+
+   /* If the block array was declared with a shared or
+    * std140 layout qualifier, all its instances have been already marked
+    * as used in link_uniform_block_active_visitor::visit(ir_variable *).
+    */
+   if (var->get_interface_type()->interface_packing ==
+       GLSL_INTERFACE_PACKING_PACKED) {
+      b->var = var;
+      process_arrays(this->mem_ctx, ir, b);
+   }
+
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+link_uniform_block_active_visitor::visit(ir_dereference_variable *ir)
+{
+   ir_variable *var = ir->var;
+
+   if (!var->is_in_buffer_block())
+      return visit_continue;
+
+   assert(!var->is_interface_instance() || !var->type->is_array());
+
+   /* Process the block.  Bail if there was an error.
+    */
+   link_uniform_block_active *const b =
+      process_block(this->mem_ctx, this->ht, var);
+   if (b == NULL) {
+      linker_error(this->prog,
+		   "uniform block `%s' has mismatching definitions",
+		   var->get_interface_type()->name);
+      this->success = false;
+      return visit_stop;
+   }
+
+   assert(b->array == NULL);
+   assert(b->type != NULL);
+
+   return visit_continue;
+}