[Mesa-dev] [RFC PATCH 08/26] glsl: select bindless sampler/image types on the fly

[Samuel Pitoiset]

At this point, there is enough information to take the decision
to replace a sampler/image type by the corresponding bindless one.

Signed-off-by: Samuel Pitoiset <samuel.pitoiset at gmail.com>
---
 src/compiler/glsl/ast.h          | 10 ++++-
 src/compiler/glsl/ast_to_hir.cpp | 93 ++++++++++++++++++++++++++++++++++++++--
 2 files changed, 98 insertions(+), 5 deletions(-)

diff --git a/src/compiler/glsl/ast.h b/src/compiler/glsl/ast.h
index 9327e03979..2a2dd4bcd9 100644
--- a/src/compiler/glsl/ast.h
+++ b/src/compiler/glsl/ast.h
@@ -894,8 +894,14 @@ public:
    }
 
    const struct glsl_type *glsl_type(const char **name,
-				     struct _mesa_glsl_parse_state *state)
-      const;
+                                     struct _mesa_glsl_parse_state *state,
+                                     bool is_interface_block = false) const;
+
+   bool is_temporary_storage() const;
+
+   bool is_bindless_type(const struct glsl_type *type,
+                         struct _mesa_glsl_parse_state *state,
+                         bool is_interface_block) const;
 
    ast_type_qualifier qualifier;
    ast_type_specifier *specifier;
diff --git a/src/compiler/glsl/ast_to_hir.cpp b/src/compiler/glsl/ast_to_hir.cpp
index 5043d6a574..4a0f3fe315 100644
--- a/src/compiler/glsl/ast_to_hir.cpp
+++ b/src/compiler/glsl/ast_to_hir.cpp
@@ -2646,9 +2646,96 @@ select_gles_precision(unsigned qual_precision,
 
 const glsl_type *
 ast_fully_specified_type::glsl_type(const char **name,
-                                    struct _mesa_glsl_parse_state *state) const
+                                    struct _mesa_glsl_parse_state *state,
+                                    bool is_interface_block) const
 {
-   return this->specifier->glsl_type(name, state);
+   const struct glsl_type *type;
+
+   type = this->specifier->glsl_type(name, state);
+   if (!type)
+      return NULL;
+
+   /* Bindless sampler/image types are replaced on-the-fly if needed as
+    * specified by ARB_bindless_texture. */
+   if (state->has_bindless()) {
+      if (type->is_sampler()) {
+         if (is_bindless_type(type, state, is_interface_block)) {
+            type = glsl_type::get_sampler_instance(
+                     (glsl_sampler_dim)type->sampler_dimensionality,
+                     type->sampler_shadow,
+                     type->sampler_array,
+                     (glsl_base_type)type->sampled_type,
+                     true);
+         }
+      }
+      if (type->is_image()) {
+         if (is_bindless_type(type, state, is_interface_block)) {
+            type = glsl_type::get_image_instance(
+                     (glsl_sampler_dim)type->sampler_dimensionality,
+                     type->sampler_array,
+                     (glsl_base_type)type->sampled_type,
+                     true);
+         }
+      }
+   }
+
+   return type;
+}
+
+bool
+ast_fully_specified_type::is_temporary_storage() const
+{
+   return (!qualifier.flags.q.in &&
+           !qualifier.flags.q.out &&
+           !qualifier.flags.q.attribute &&
+           !qualifier.flags.q.varying &&
+           !qualifier.flags.q.uniform &&
+           !qualifier.flags.q.buffer &&
+           !qualifier.flags.q.shared_storage);
+}
+
+bool
+ast_fully_specified_type::is_bindless_type(const struct glsl_type *type,
+                                           struct _mesa_glsl_parse_state *state,
+                                           bool is_interface_block) const
+{
+   /* The bindless_sampler (and respectively bindless_image) layout qualifiers
+    * can be set as local scope, as well as at global scope. */
+   if (qualifier.flags.q.bindless_sampler ||
+       qualifier.flags.q.bindless_image ||
+       state->bindless_sampler_specified ||
+       state->bindless_image_specified)
+      return true;
+
+   /* The ARB_bindless_texture spec says:
+    *
+    * "Modify Section 4.3.7, Interface Blocks, p. 38"
+    *
+    * "(remove the following bullet from the last list on p. 39, thereby
+    *  permitting sampler types in interface blocks; image types are also
+    *  permitted in blocks by this extension)"
+    *
+    *    * sampler types are not allowed
+    */
+   if (is_interface_block)
+      return true;
+
+   /* The ARB_bindless_texture spec says:
+    *
+    * "Replace Section 4.1.7 (Samplers), p. 25"
+    *
+    * "Samplers may be declared as shader inputs and outputs, as uniform
+    *  variables, as temporary variables, and as function parameters"
+    *
+    * "Replace Section 4.1.X, (Images)"
+    *
+    * "Images may be declared as shader inputs and outputs, as uniform
+    *  variables, as temporary variables, and as function parameters."
+    */
+   if (qualifier.flags.q.in || qualifier.flags.q.out || is_temporary_storage())
+      return true;
+
+   return false;
 }
 
 /**
@@ -6844,7 +6931,7 @@ ast_process_struct_or_iface_block_members(exec_list *instructions,
                           "embedded structure declarations are not allowed");
 
       const glsl_type *decl_type =
-         decl_list->type->glsl_type(& type_name, state);
+         decl_list->type->glsl_type(& type_name, state, is_interface);
 
       const struct ast_type_qualifier *const qual =
          &decl_list->type->qualifier;
-- 
2.12.2