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, 453 insertions, 0 deletions

diff --git a/src/compiler/glsl/ir_set_program_inouts.cpp b/src/compiler/glsl/ir_set_program_inouts.cpp
new file mode 100644
index 00000000000..df06923b870
--- /dev/null
+++ b/src/compiler/glsl/ir_set_program_inouts.cpp
@@ -0,0 +1,453 @@
+/*
+ * 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 ir_set_program_inouts.cpp
+ *
+ * Sets the InputsRead and OutputsWritten of Mesa programs.
+ *
+ * Additionally, for fragment shaders, sets the InterpQualifier array, the
+ * IsCentroid and IsSample bitfields, and the UsesDFdy flag.
+ *
+ * Mesa programs (gl_program, not gl_shader_program) have a set of
+ * flags indicating which varyings are read and written.  Computing
+ * which are actually read from some sort of backend code can be
+ * tricky when variable array indexing involved.  So this pass
+ * provides support for setting InputsRead and OutputsWritten right
+ * from the GLSL IR.
+ */
+
+#include "main/core.h" /* for struct gl_program */
+#include "ir.h"
+#include "ir_visitor.h"
+#include "compiler/glsl_types.h"
+
+namespace {
+
+class ir_set_program_inouts_visitor : public ir_hierarchical_visitor {
+public:
+   ir_set_program_inouts_visitor(struct gl_program *prog,
+                                 gl_shader_stage shader_stage)
+   {
+      this->prog = prog;
+      this->shader_stage = shader_stage;
+   }
+   ~ir_set_program_inouts_visitor()
+   {
+   }
+
+   virtual ir_visitor_status visit_enter(ir_dereference_array *);
+   virtual ir_visitor_status visit_enter(ir_function_signature *);
+   virtual ir_visitor_status visit_enter(ir_expression *);
+   virtual ir_visitor_status visit_enter(ir_discard *);
+   virtual ir_visitor_status visit_enter(ir_texture *);
+   virtual ir_visitor_status visit(ir_dereference_variable *);
+
+private:
+   void mark_whole_variable(ir_variable *var);
+   bool try_mark_partial_variable(ir_variable *var, ir_rvalue *index);
+
+   struct gl_program *prog;
+   gl_shader_stage shader_stage;
+};
+
+} /* anonymous namespace */
+
+static inline bool
+is_shader_inout(ir_variable *var)
+{
+   return var->data.mode == ir_var_shader_in ||
+          var->data.mode == ir_var_shader_out ||
+          var->data.mode == ir_var_system_value;
+}
+
+static void
+mark(struct gl_program *prog, ir_variable *var, int offset, int len,
+     gl_shader_stage stage)
+{
+   /* As of GLSL 1.20, varyings can only be floats, floating-point
+    * vectors or matrices, or arrays of them.  For Mesa programs using
+    * InputsRead/OutputsWritten, everything but matrices uses one
+    * slot, while matrices use a slot per column.  Presumably
+    * something doing a more clever packing would use something other
+    * than InputsRead/OutputsWritten.
+    */
+
+   for (int i = 0; i < len; i++) {
+      int idx = var->data.location + var->data.index + offset + i;
+      bool is_patch_generic = var->data.patch &&
+                              idx != VARYING_SLOT_TESS_LEVEL_INNER &&
+                              idx != VARYING_SLOT_TESS_LEVEL_OUTER;
+      GLbitfield64 bitfield;
+
+      if (is_patch_generic) {
+         assert(idx >= VARYING_SLOT_PATCH0 && idx < VARYING_SLOT_TESS_MAX);
+         bitfield = BITFIELD64_BIT(idx - VARYING_SLOT_PATCH0);
+      }
+      else {
+         assert(idx < VARYING_SLOT_MAX);
+         bitfield = BITFIELD64_BIT(idx);
+      }
+
+      if (var->data.mode == ir_var_shader_in) {
+         if (is_patch_generic)
+            prog->PatchInputsRead |= bitfield;
+         else
+            prog->InputsRead |= bitfield;
+
+         /* double inputs read is only for vertex inputs */
+         if (stage == MESA_SHADER_VERTEX &&
+             var->type->without_array()->is_dual_slot_double())
+            prog->DoubleInputsRead |= bitfield;
+
+         if (stage == MESA_SHADER_FRAGMENT) {
+            gl_fragment_program *fprog = (gl_fragment_program *) prog;
+            fprog->InterpQualifier[idx] =
+               (glsl_interp_qualifier) var->data.interpolation;
+            if (var->data.centroid)
+               fprog->IsCentroid |= bitfield;
+            if (var->data.sample)
+               fprog->IsSample |= bitfield;
+         }
+      } else if (var->data.mode == ir_var_system_value) {
+         prog->SystemValuesRead |= bitfield;
+      } else {
+         assert(var->data.mode == ir_var_shader_out);
+         if (is_patch_generic)
+            prog->PatchOutputsWritten |= bitfield;
+         else
+            prog->OutputsWritten |= bitfield;
+      }
+   }
+}
+
+/**
+ * Mark an entire variable as used.  Caller must ensure that the variable
+ * represents a shader input or output.
+ */
+void
+ir_set_program_inouts_visitor::mark_whole_variable(ir_variable *var)
+{
+   const glsl_type *type = var->type;
+   bool vertex_input = false;
+   if (this->shader_stage == MESA_SHADER_GEOMETRY &&
+       var->data.mode == ir_var_shader_in && type->is_array()) {
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_CTRL &&
+       var->data.mode == ir_var_shader_in) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_CTRL &&
+       var->data.mode == ir_var_shader_out && !var->data.patch) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_EVAL &&
+       var->data.mode == ir_var_shader_in && !var->data.patch) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_VERTEX &&
+       var->data.mode == ir_var_shader_in)
+      vertex_input = true;
+
+   mark(this->prog, var, 0, type->count_attribute_slots(vertex_input),
+        this->shader_stage);
+}
+
+/* Default handler: Mark all the locations in the variable as used. */
+ir_visitor_status
+ir_set_program_inouts_visitor::visit(ir_dereference_variable *ir)
+{
+   if (!is_shader_inout(ir->var))
+      return visit_continue;
+
+   mark_whole_variable(ir->var);
+
+   return visit_continue;
+}
+
+/**
+ * Try to mark a portion of the given variable as used.  Caller must ensure
+ * that the variable represents a shader input or output which can be indexed
+ * into in array fashion (an array or matrix).  For the purpose of geometry
+ * shader inputs (which are always arrays*), this means that the array element
+ * must be something that can be indexed into in array fashion.
+ *
+ * *Except gl_PrimitiveIDIn, as noted below.
+ *
+ * For tessellation control shaders all inputs and non-patch outputs are
+ * arrays. For tessellation evaluation shaders non-patch inputs are arrays.
+ *
+ * If the index can't be interpreted as a constant, or some other problem
+ * occurs, then nothing will be marked and false will be returned.
+ */
+bool
+ir_set_program_inouts_visitor::try_mark_partial_variable(ir_variable *var,
+                                                         ir_rvalue *index)
+{
+   const glsl_type *type = var->type;
+
+   if (this->shader_stage == MESA_SHADER_GEOMETRY &&
+       var->data.mode == ir_var_shader_in) {
+      /* The only geometry shader input that is not an array is
+       * gl_PrimitiveIDIn, and in that case, this code will never be reached,
+       * because gl_PrimitiveIDIn can't be indexed into in array fashion.
+       */
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_CTRL &&
+       var->data.mode == ir_var_shader_in) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_CTRL &&
+       var->data.mode == ir_var_shader_out && !var->data.patch) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   if (this->shader_stage == MESA_SHADER_TESS_EVAL &&
+       var->data.mode == ir_var_shader_in && !var->data.patch) {
+      assert(type->is_array());
+      type = type->fields.array;
+   }
+
+   /* TODO: implement proper arrays of arrays support
+    * for now let the caller mark whole variable as used.
+    */
+   if (type->is_array() && type->fields.array->is_array())
+      return false;
+
+   /* The code below only handles:
+    *
+    * - Indexing into matrices
+    * - Indexing into arrays of (matrices, vectors, or scalars)
+    *
+    * All other possibilities are either prohibited by GLSL (vertex inputs and
+    * fragment outputs can't be structs) or should have been eliminated by
+    * lowering passes (do_vec_index_to_swizzle() gets rid of indexing into
+    * vectors, and lower_packed_varyings() gets rid of structs that occur in
+    * varyings).
+    */
+   if (!(type->is_matrix() ||
+        (type->is_array() &&
+         (type->fields.array->is_numeric() ||
+          type->fields.array->is_boolean())))) {
+      assert(!"Unexpected indexing in ir_set_program_inouts");
+
+      /* For safety in release builds, in case we ever encounter unexpected
+       * indexing, give up and let the caller mark the whole variable as used.
+       */
+      return false;
+   }
+
+   ir_constant *index_as_constant = index->as_constant();
+   if (!index_as_constant)
+      return false;
+
+   unsigned elem_width;
+   unsigned num_elems;
+   if (type->is_array()) {
+      num_elems = type->length;
+      if (type->fields.array->is_matrix())
+         elem_width = type->fields.array->matrix_columns;
+      else
+         elem_width = 1;
+   } else {
+      num_elems = type->matrix_columns;
+      elem_width = 1;
+   }
+
+   if (index_as_constant->value.u[0] >= num_elems) {
+      /* Constant index outside the bounds of the matrix/array.  This could
+       * arise as a result of constant folding of a legal GLSL program.
+       *
+       * Even though the spec says that indexing outside the bounds of a
+       * matrix/array results in undefined behaviour, we don't want to pass
+       * out-of-range values to mark() (since this could result in slots that
+       * don't exist being marked as used), so just let the caller mark the
+       * whole variable as used.
+       */
+      return false;
+   }
+
+   /* double element width for double types that takes two slots */
+   if (this->shader_stage != MESA_SHADER_VERTEX ||
+       var->data.mode != ir_var_shader_in) {
+      if (type->without_array()->is_dual_slot_double())
+	 elem_width *= 2;
+   }
+
+   mark(this->prog, var, index_as_constant->value.u[0] * elem_width,
+        elem_width, this->shader_stage);
+   return true;
+}
+
+static bool
+is_multiple_vertices(gl_shader_stage stage, ir_variable *var)
+{
+   if (var->data.patch)
+      return false;
+
+   if (var->data.mode == ir_var_shader_in)
+      return stage == MESA_SHADER_GEOMETRY ||
+             stage == MESA_SHADER_TESS_CTRL ||
+             stage == MESA_SHADER_TESS_EVAL;
+   if (var->data.mode == ir_var_shader_out)
+      return stage == MESA_SHADER_TESS_CTRL;
+
+   return false;
+}
+
+ir_visitor_status
+ir_set_program_inouts_visitor::visit_enter(ir_dereference_array *ir)
+{
+   /* Note: for geometry shader inputs, lower_named_interface_blocks may
+    * create 2D arrays, so we need to be able to handle those.  2D arrays
+    * shouldn't be able to crop up for any other reason.
+    */
+   if (ir_dereference_array * const inner_array =
+       ir->array->as_dereference_array()) {
+      /*          ir => foo[i][j]
+       * inner_array => foo[i]
+       */
+      if (ir_dereference_variable * const deref_var =
+          inner_array->array->as_dereference_variable()) {
+         if (is_multiple_vertices(this->shader_stage, deref_var->var)) {
+            /* foo is a geometry or tessellation shader input, so i is
+             * the vertex, and j the part of the input we're accessing.
+             */
+            if (try_mark_partial_variable(deref_var->var, ir->array_index))
+            {
+               /* We've now taken care of foo and j, but i might contain a
+                * subexpression that accesses shader inputs.  So manually
+                * visit i and then continue with the parent.
+                */
+               inner_array->array_index->accept(this);
+               return visit_continue_with_parent;
+            }
+         }
+      }
+   } else if (ir_dereference_variable * const deref_var =
+              ir->array->as_dereference_variable()) {
+      /* ir => foo[i], where foo is a variable. */
+      if (is_multiple_vertices(this->shader_stage, deref_var->var)) {
+         /* foo is a geometry or tessellation shader input, so i is
+          * the vertex, and we're accessing the entire input.
+          */
+         mark_whole_variable(deref_var->var);
+         /* We've now taken care of foo, but i might contain a subexpression
+          * that accesses shader inputs.  So manually visit i and then
+          * continue with the parent.
+          */
+         ir->array_index->accept(this);
+         return visit_continue_with_parent;
+      } else if (is_shader_inout(deref_var->var)) {
+         /* foo is a shader input/output, but not a geometry shader input,
+          * so i is the part of the input we're accessing.
+          */
+         if (try_mark_partial_variable(deref_var->var, ir->array_index))
+            return visit_continue_with_parent;
+      }
+   }
+
+   /* The expression is something we don't recognize.  Just visit its
+    * subexpressions.
+    */
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_set_program_inouts_visitor::visit_enter(ir_function_signature *ir)
+{
+   /* We don't want to descend into the function parameters and
+    * consider them as shader inputs or outputs.
+    */
+   visit_list_elements(this, &ir->body);
+   return visit_continue_with_parent;
+}
+
+ir_visitor_status
+ir_set_program_inouts_visitor::visit_enter(ir_expression *ir)
+{
+   if (this->shader_stage == MESA_SHADER_FRAGMENT &&
+       (ir->operation == ir_unop_dFdy ||
+        ir->operation == ir_unop_dFdy_coarse ||
+        ir->operation == ir_unop_dFdy_fine)) {
+      gl_fragment_program *fprog = (gl_fragment_program *) prog;
+      fprog->UsesDFdy = true;
+   }
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_set_program_inouts_visitor::visit_enter(ir_discard *)
+{
+   /* discards are only allowed in fragment shaders. */
+   assert(this->shader_stage == MESA_SHADER_FRAGMENT);
+
+   gl_fragment_program *fprog = (gl_fragment_program *) prog;
+   fprog->UsesKill = true;
+
+   return visit_continue;
+}
+
+ir_visitor_status
+ir_set_program_inouts_visitor::visit_enter(ir_texture *ir)
+{
+   if (ir->op == ir_tg4)
+      prog->UsesGather = true;
+   return visit_continue;
+}
+
+void
+do_set_program_inouts(exec_list *instructions, struct gl_program *prog,
+                      gl_shader_stage shader_stage)
+{
+   ir_set_program_inouts_visitor v(prog, shader_stage);
+
+   prog->InputsRead = 0;
+   prog->OutputsWritten = 0;
+   prog->PatchInputsRead = 0;
+   prog->PatchOutputsWritten = 0;
+   prog->SystemValuesRead = 0;
+   if (shader_stage == MESA_SHADER_FRAGMENT) {
+      gl_fragment_program *fprog = (gl_fragment_program *) prog;
+      memset(fprog->InterpQualifier, 0, sizeof(fprog->InterpQualifier));
+      fprog->IsCentroid = 0;
+      fprog->IsSample = 0;
+      fprog->UsesDFdy = false;
+      fprog->UsesKill = false;
+   }
+   visit_list_elements(&v, instructions);
+}