glsl: move to compiler/

Signed-off-by: Emil Velikov <[email protected]>
Acked-by: Matt Turner <[email protected]>
Acked-by: Jose Fonseca <[email protected]>

1 files changed, 333 insertions, 0 deletions

diff --git a/src/compiler/glsl/ast_array_index.cpp b/src/compiler/glsl/ast_array_index.cpp
new file mode 100644
index 00000000000..f5baeb9ea32
--- /dev/null
+++ b/src/compiler/glsl/ast_array_index.cpp
@@ -0,0 +1,333 @@
+/*
+ * 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.
+ */
+
+#include "ast.h"
+#include "compiler/glsl_types.h"
+#include "ir.h"
+
+void
+ast_array_specifier::print(void) const
+{
+   foreach_list_typed (ast_node, array_dimension, link, &this->array_dimensions) {
+      printf("[ ");
+      if (((ast_expression*)array_dimension)->oper != ast_unsized_array_dim)
+         array_dimension->print();
+      printf("] ");
+   }
+}
+
+/**
+ * If \c ir is a reference to an array for which we are tracking the max array
+ * element accessed, track that the given element has been accessed.
+ * Otherwise do nothing.
+ *
+ * This function also checks whether the array is a built-in array whose
+ * maximum size is too small to accommodate the given index, and if so uses
+ * loc and state to report the error.
+ */
+static void
+update_max_array_access(ir_rvalue *ir, int idx, YYLTYPE *loc,
+                        struct _mesa_glsl_parse_state *state)
+{
+   if (ir_dereference_variable *deref_var = ir->as_dereference_variable()) {
+      ir_variable *var = deref_var->var;
+      if (idx > (int)var->data.max_array_access) {
+         var->data.max_array_access = idx;
+
+         /* Check whether this access will, as a side effect, implicitly cause
+          * the size of a built-in array to be too large.
+          */
+         check_builtin_array_max_size(var->name, idx+1, *loc, state);
+      }
+   } else if (ir_dereference_record *deref_record =
+              ir->as_dereference_record()) {
+      /* There are three possibilities we need to consider:
+       *
+       * - Accessing an element of an array that is a member of a named
+       *   interface block (e.g. ifc.foo[i])
+       *
+       * - Accessing an element of an array that is a member of a named
+       *   interface block array (e.g. ifc[j].foo[i]).
+       *
+       * - Accessing an element of an array that is a member of a named
+       *   interface block array of arrays (e.g. ifc[j][k].foo[i]).
+       */
+      ir_dereference_variable *deref_var =
+         deref_record->record->as_dereference_variable();
+      if (deref_var == NULL) {
+         ir_dereference_array *deref_array =
+            deref_record->record->as_dereference_array();
+         ir_dereference_array *deref_array_prev = NULL;
+         while (deref_array != NULL) {
+            deref_array_prev = deref_array;
+            deref_array = deref_array->array->as_dereference_array();
+         }
+         if (deref_array_prev != NULL)
+            deref_var = deref_array_prev->array->as_dereference_variable();
+      }
+
+      if (deref_var != NULL) {
+         if (deref_var->var->is_interface_instance()) {
+            unsigned field_index =
+               deref_record->record->type->field_index(deref_record->field);
+            assert(field_index < deref_var->var->get_interface_type()->length);
+
+            unsigned *const max_ifc_array_access =
+               deref_var->var->get_max_ifc_array_access();
+
+            assert(max_ifc_array_access != NULL);
+
+            if (idx > (int)max_ifc_array_access[field_index]) {
+               max_ifc_array_access[field_index] = idx;
+
+               /* Check whether this access will, as a side effect, implicitly
+                * cause the size of a built-in array to be too large.
+                */
+               check_builtin_array_max_size(deref_record->field, idx+1, *loc,
+                                            state);
+            }
+         }
+      }
+   }
+}
+
+
+static int
+get_implicit_array_size(struct _mesa_glsl_parse_state *state,
+                        ir_rvalue *array)
+{
+   ir_variable *var = array->variable_referenced();
+
+   /* Inputs in control shader are implicitly sized
+    * to the maximum patch size.
+    */
+   if (state->stage == MESA_SHADER_TESS_CTRL &&
+       var->data.mode == ir_var_shader_in) {
+      return state->Const.MaxPatchVertices;
+   }
+
+   /* Non-patch inputs in evaluation shader are implicitly sized
+    * to the maximum patch size.
+    */
+   if (state->stage == MESA_SHADER_TESS_EVAL &&
+       var->data.mode == ir_var_shader_in &&
+       !var->data.patch) {
+      return state->Const.MaxPatchVertices;
+   }
+
+   return 0;
+}
+
+
+ir_rvalue *
+_mesa_ast_array_index_to_hir(void *mem_ctx,
+			     struct _mesa_glsl_parse_state *state,
+			     ir_rvalue *array, ir_rvalue *idx,
+			     YYLTYPE &loc, YYLTYPE &idx_loc)
+{
+   if (!array->type->is_error()
+       && !array->type->is_array()
+       && !array->type->is_matrix()
+       && !array->type->is_vector()) {
+      _mesa_glsl_error(& idx_loc, state,
+		       "cannot dereference non-array / non-matrix / "
+		       "non-vector");
+   }
+
+   if (!idx->type->is_error()) {
+      if (!idx->type->is_integer()) {
+	 _mesa_glsl_error(& idx_loc, state, "array index must be integer type");
+      } else if (!idx->type->is_scalar()) {
+	 _mesa_glsl_error(& idx_loc, state, "array index must be scalar");
+      }
+   }
+
+   /* If the array index is a constant expression and the array has a
+    * declared size, ensure that the access is in-bounds.  If the array
+    * index is not a constant expression, ensure that the array has a
+    * declared size.
+    */
+   ir_constant *const const_index = idx->constant_expression_value();
+   if (const_index != NULL && idx->type->is_integer()) {
+      const int idx = const_index->value.i[0];
+      const char *type_name = "error";
+      unsigned bound = 0;
+
+      /* From page 24 (page 30 of the PDF) of the GLSL 1.50 spec:
+       *
+       *    "It is illegal to declare an array with a size, and then
+       *    later (in the same shader) index the same array with an
+       *    integral constant expression greater than or equal to the
+       *    declared size. It is also illegal to index an array with a
+       *    negative constant expression."
+       */
+      if (array->type->is_matrix()) {
+	 if (array->type->row_type()->vector_elements <= idx) {
+	    type_name = "matrix";
+	    bound = array->type->row_type()->vector_elements;
+	 }
+      } else if (array->type->is_vector()) {
+	 if (array->type->vector_elements <= idx) {
+	    type_name = "vector";
+	    bound = array->type->vector_elements;
+	 }
+      } else {
+	 /* glsl_type::array_size() returns -1 for non-array types.  This means
+	  * that we don't need to verify that the type is an array before
+	  * doing the bounds checking.
+	  */
+	 if ((array->type->array_size() > 0)
+	     && (array->type->array_size() <= idx)) {
+	    type_name = "array";
+	    bound = array->type->array_size();
+	 }
+      }
+
+      if (bound > 0) {
+	 _mesa_glsl_error(& loc, state, "%s index must be < %u",
+			  type_name, bound);
+      } else if (idx < 0) {
+	 _mesa_glsl_error(& loc, state, "%s index must be >= 0",
+			  type_name);
+      }
+
+      if (array->type->is_array())
+         update_max_array_access(array, idx, &loc, state);
+   } else if (const_index == NULL && array->type->is_array()) {
+      if (array->type->is_unsized_array()) {
+         int implicit_size = get_implicit_array_size(state, array);
+         if (implicit_size) {
+            ir_variable *v = array->whole_variable_referenced();
+            if (v != NULL)
+               v->data.max_array_access = implicit_size - 1;
+         }
+         else if (state->stage == MESA_SHADER_TESS_CTRL &&
+                  array->variable_referenced()->data.mode == ir_var_shader_out &&
+                  !array->variable_referenced()->data.patch) {
+            /* Tessellation control shader output non-patch arrays are
+             * initially unsized. Despite that, they are allowed to be
+             * indexed with a non-constant expression (typically
+             * "gl_InvocationID"). The array size will be determined
+             * by the linker.
+             */
+         }
+         else if (array->variable_referenced()->data.mode !=
+                  ir_var_shader_storage) {
+            _mesa_glsl_error(&loc, state, "unsized array index must be constant");
+         }
+      } else if (array->type->without_array()->is_interface()
+                 && (array->variable_referenced()->data.mode == ir_var_uniform ||
+                     array->variable_referenced()->data.mode == ir_var_shader_storage)
+                 && !state->is_version(400, 0) && !state->ARB_gpu_shader5_enable) {
+	 /* Page 50 in section 4.3.9 of the OpenGL ES 3.10 spec says:
+	  *
+	  *     "All indices used to index a uniform or shader storage block
+	  *     array must be constant integral expressions."
+	  */
+	 _mesa_glsl_error(&loc, state, "%s block array index must be constant",
+                          array->variable_referenced()->data.mode
+                          == ir_var_uniform ? "uniform" : "shader storage");
+      } else {
+	 /* whole_variable_referenced can return NULL if the array is a
+	  * member of a structure.  In this case it is safe to not update
+	  * the max_array_access field because it is never used for fields
+	  * of structures.
+	  */
+	 ir_variable *v = array->whole_variable_referenced();
+	 if (v != NULL)
+	    v->data.max_array_access = array->type->array_size() - 1;
+      }
+
+      /* From page 23 (29 of the PDF) of the GLSL 1.30 spec:
+       *
+       *    "Samplers aggregated into arrays within a shader (using square
+       *    brackets [ ]) can only be indexed with integral constant
+       *    expressions [...]."
+       *
+       * This restriction was added in GLSL 1.30.  Shaders using earlier
+       * version of the language should not be rejected by the compiler
+       * front-end for using this construct.  This allows useful things such
+       * as using a loop counter as the index to an array of samplers.  If the
+       * loop in unrolled, the code should compile correctly.  Instead, emit a
+       * warning.
+       *
+       * In GLSL 4.00 / ARB_gpu_shader5, this requirement is relaxed again to allow
+       * indexing with dynamically uniform expressions. Note that these are not
+       * required to be uniforms or expressions based on them, but merely that the
+       * values must not diverge between shader invocations run together. If the
+       * values *do* diverge, then the behavior of the operation requiring a
+       * dynamically uniform expression is undefined.
+       */
+      if (array->type->without_array()->is_sampler()) {
+         if (!state->is_version(400, 0) && !state->ARB_gpu_shader5_enable) {
+            if (state->is_version(130, 300))
+               _mesa_glsl_error(&loc, state,
+                                "sampler arrays indexed with non-constant "
+                                "expressions are forbidden in GLSL %s "
+                                "and later",
+                                state->es_shader ? "ES 3.00" : "1.30");
+            else if (state->es_shader)
+               _mesa_glsl_warning(&loc, state,
+                                  "sampler arrays indexed with non-constant "
+                                  "expressions will be forbidden in GLSL "
+                                  "3.00 and later");
+            else
+               _mesa_glsl_warning(&loc, state,
+                                  "sampler arrays indexed with non-constant "
+                                  "expressions will be forbidden in GLSL "
+                                  "1.30 and later");
+         }
+      }
+
+      /* From page 27 of the GLSL ES 3.1 specification:
+       *
+       * "When aggregated into arrays within a shader, images can only be
+       *  indexed with a constant integral expression."
+       *
+       * On the other hand the desktop GL specification extension allows
+       * non-constant indexing of image arrays, but behavior is left undefined
+       * in cases where the indexing expression is not dynamically uniform.
+       */
+      if (state->es_shader && array->type->without_array()->is_image()) {
+         _mesa_glsl_error(&loc, state,
+                          "image arrays indexed with non-constant "
+                          "expressions are forbidden in GLSL ES.");
+      }
+   }
+
+   /* After performing all of the error checking, generate the IR for the
+    * expression.
+    */
+   if (array->type->is_array()
+       || array->type->is_matrix()
+       || array->type->is_vector()) {
+      return new(mem_ctx) ir_dereference_array(array, idx);
+   } else if (array->type->is_error()) {
+      return array;
+   } else {
+      ir_rvalue *result = new(mem_ctx) ir_dereference_array(array, idx);
+      result->type = glsl_type::error_type;
+
+      return result;
+   }
+}