glsl: reuse main extension table to appropriately restrict extensions

Previously we were only restricting based on ES/non-ES-ness and whether
the overall enable bit had been flipped on. However we have been adding
more fine-grained restrictions, such as based on compat profiles, as
well as specific ES versions. Most of the time this doesn't matter, but
it can create awkward situations and duplication of logic.

Here we separate the main extension table into a separate object file,
linked to the glsl compiler, which makes use of it with a custom
function which takes the ES-ness of the shader into account (thus
allowing desktop shaders to properly use ES extensions that would
otherwise have been disallowed.) We can also now use this logic to
generate #define's for all supported extensions automatically, removing
the duplicate (and often inaccurate) list in glcpp.

The effect of this change should be nil in most cases. However in some
situations, extensions like GL_ARB_gpu_shader5 which were formerly
available in compat contexts on the GLSL side of things will now become
inaccessible.

This regresses two ES CTS tests:

  ES3-CTS.shaders.shader_integer_mix.define
  ES31-CTS.shader_integer_mix.define

however that is due to them using #version 100 instead of 300 es. As the
extension is only defined for ES3, I believe this is the correct
behavior.

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Eric Engestrom <eric.engestrom@imgtec.com> (v2)
v2 -> v3: integrate glcpp defines into the same mechanism

1 files changed, 159 insertions, 122 deletions

diff --git a/src/compiler/glsl/glsl_parser_extras.cpp b/src/compiler/glsl/glsl_parser_extras.cpp
index 0077434..ff638fd 100644
--- a/src/compiler/glsl/glsl_parser_extras.cpp
+++ b/src/compiler/glsl/glsl_parser_extras.cpp
@@ -50,6 +50,8 @@ glsl_compute_version_string(void *mem_ctx, bool is_es, unsigned version)
 
 static const unsigned known_desktop_glsl_versions[] =
    { 110, 120, 130, 140, 150, 330, 400, 410, 420, 430, 440, 450 };
+static const unsigned known_desktop_gl_versions[] =
+   {  20,  21,  30,  31,  32,  33,  40,  41,  42,  43,  44,  45 };
 
 
 _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
@@ -75,6 +77,7 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
    this->language_version = 110;
    this->forced_language_version = ctx->Const.ForceGLSLVersion;
    this->zero_init = ctx->Const.GLSLZeroInit;
+   this->gl_version = 20;
    this->es_shader = false;
    this->ARB_texture_rectangle_enable = true;
 
@@ -195,9 +198,9 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
    this->subroutine_types = NULL;
 
    /* supported_versions should be large enough to support the known desktop
-    * GLSL versions plus 3 GLES versions (ES 1.00, ES 3.00, and ES 3.10))
+    * GLSL versions plus 4 GLES versions (ES 1.00, ES 3.00, ES 3.10, ES 3.20)
     */
-   STATIC_ASSERT((ARRAY_SIZE(known_desktop_glsl_versions) + 3) ==
+   STATIC_ASSERT((ARRAY_SIZE(known_desktop_glsl_versions) + 4) ==
                  ARRAY_SIZE(this->supported_versions));
 
    /* Populate the list of supported GLSL versions */
@@ -212,6 +215,8 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
          if (known_desktop_glsl_versions[i] <= ctx->Const.GLSLVersion) {
             this->supported_versions[this->num_supported_versions].ver
                = known_desktop_glsl_versions[i];
+            this->supported_versions[this->num_supported_versions].gl_ver
+               = known_desktop_gl_versions[i];
             this->supported_versions[this->num_supported_versions].es = false;
             this->num_supported_versions++;
          }
@@ -219,22 +224,26 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
    }
    if (ctx->API == API_OPENGLES2 || ctx->Extensions.ARB_ES2_compatibility) {
       this->supported_versions[this->num_supported_versions].ver = 100;
+      this->supported_versions[this->num_supported_versions].gl_ver = 20;
       this->supported_versions[this->num_supported_versions].es = true;
       this->num_supported_versions++;
    }
    if (_mesa_is_gles3(ctx) || ctx->Extensions.ARB_ES3_compatibility) {
       this->supported_versions[this->num_supported_versions].ver = 300;
+      this->supported_versions[this->num_supported_versions].gl_ver = 30;
       this->supported_versions[this->num_supported_versions].es = true;
       this->num_supported_versions++;
    }
    if (_mesa_is_gles31(ctx) || ctx->Extensions.ARB_ES3_1_compatibility) {
       this->supported_versions[this->num_supported_versions].ver = 310;
+      this->supported_versions[this->num_supported_versions].gl_ver = 31;
       this->supported_versions[this->num_supported_versions].es = true;
       this->num_supported_versions++;
    }
    if ((ctx->API == API_OPENGLES2 && ctx->Version >= 32) ||
        ctx->Extensions.ARB_ES3_2_compatibility) {
       this->supported_versions[this->num_supported_versions].ver = 320;
+      this->supported_versions[this->num_supported_versions].gl_ver = 32;
       this->supported_versions[this->num_supported_versions].es = true;
       this->num_supported_versions++;
    }
@@ -399,6 +408,7 @@ _mesa_glsl_parse_state::process_version_directive(YYLTYPE *locp, int version,
    for (unsigned i = 0; i < this->num_supported_versions; i++) {
       if (this->supported_versions[i].ver == this->language_version
           && this->supported_versions[i].es == this->es_shader) {
+         this->gl_version = this->supported_versions[i].gl_ver;
          supported = true;
          break;
       }
@@ -511,28 +521,12 @@ struct _mesa_glsl_extension {
     */
    const char *name;
 
-   /** True if this extension is available to desktop GL shaders */
-   bool avail_in_GL;
-
-   /** True if this extension is available to GLES shaders */
-   bool avail_in_ES;
-
    /**
-    * Flag in the gl_extensions struct indicating whether this
-    * extension is supported by the driver, or
-    * &gl_extensions::dummy_true if supported by all drivers.
-    *
-    * Note: the type (GLboolean gl_extensions::*) is a "pointer to
-    * member" type, the type-safe alternative to the "offsetof" macro.
-    * In a nutshell:
-    *
-    * - foo bar::* p declares p to be an "offset" to a field of type
-    *   foo that exists within struct bar
-    * - &bar::baz computes the "offset" of field baz within struct bar
-    * - x.*p accesses the field of x that exists at "offset" p
-    * - x->*p is equivalent to (*x).*p
+    * Predicate that checks whether the relevant extension is available for
+    * this context.
     */
-   const GLboolean gl_extensions::* supported_flag;
+   bool (*available_pred)(const struct gl_context *,
+                          gl_api api, uint8_t version);
 
    /**
     * Flag in the _mesa_glsl_parse_state struct that should be set
@@ -553,12 +547,24 @@ struct _mesa_glsl_extension {
    bool _mesa_glsl_parse_state::* warn_flag;
 
 
-   bool compatible_with_state(const _mesa_glsl_parse_state *state) const;
+   bool compatible_with_state(const _mesa_glsl_parse_state *state,
+                              gl_api api, uint8_t gl_version) const;
    void set_flags(_mesa_glsl_parse_state *state, ext_behavior behavior) const;
 };
 
-#define EXT(NAME, GL, ES, SUPPORTED_FLAG)                   \
-   { "GL_" #NAME, GL, ES, &gl_extensions::SUPPORTED_FLAG,   \
+/** Checks if the context supports a user-facing extension */
+#define EXT(name_str, driver_cap, ...) \
+static MAYBE_UNUSED bool \
+has_##name_str(const struct gl_context *ctx, gl_api api, uint8_t version) \
+{ \
+   return ctx->Extensions.driver_cap && (version >= \
+          _mesa_extension_table[MESA_EXTENSION_##name_str].version[api]); \
+}
+#include "main/extensions_table.h"
+#undef EXT
+
+#define EXT(NAME)                                           \
+   { "GL_" #NAME, has_##NAME,                         \
          &_mesa_glsl_parse_state::NAME##_enable,            \
          &_mesa_glsl_parse_state::NAME##_warn }
 
@@ -567,92 +573,89 @@ struct _mesa_glsl_extension {
  * and the conditions under which they are supported.
  */
 static const _mesa_glsl_extension _mesa_glsl_supported_extensions[] = {
-   /*                                  API availability */
-   /* name                             GL     ES         supported flag */
-
    /* ARB extensions go here, sorted alphabetically.
     */
-   EXT(ARB_ES3_1_compatibility,          true,  false,     ARB_ES3_1_compatibility),
-   EXT(ARB_ES3_2_compatibility,          true,  false,     ARB_ES3_2_compatibility),
-   EXT(ARB_arrays_of_arrays,             true,  false,     ARB_arrays_of_arrays),
-   EXT(ARB_compute_shader,               true,  false,     ARB_compute_shader),
-   EXT(ARB_conservative_depth,           true,  false,     ARB_conservative_depth),
-   EXT(ARB_cull_distance,                true,  false,     ARB_cull_distance),
-   EXT(ARB_derivative_control,           true,  false,     ARB_derivative_control),
-   EXT(ARB_draw_buffers,                 true,  false,     dummy_true),
-   EXT(ARB_draw_instanced,               true,  false,     ARB_draw_instanced),
-   EXT(ARB_enhanced_layouts,             true,  false,     ARB_enhanced_layouts),
-   EXT(ARB_explicit_attrib_location,     true,  false,     ARB_explicit_attrib_location),
-   EXT(ARB_explicit_uniform_location,    true,  false,     ARB_explicit_uniform_location),
-   EXT(ARB_fragment_coord_conventions,   true,  false,     ARB_fragment_coord_conventions),
-   EXT(ARB_fragment_layer_viewport,      true,  false,     ARB_fragment_layer_viewport),
-   EXT(ARB_gpu_shader5,                  true,  false,     ARB_gpu_shader5),
-   EXT(ARB_gpu_shader_fp64,              true,  false,     ARB_gpu_shader_fp64),
-   EXT(ARB_sample_shading,               true,  false,     ARB_sample_shading),
-   EXT(ARB_separate_shader_objects,      true,  false,     dummy_true),
-   EXT(ARB_shader_atomic_counter_ops,    true,  false,     ARB_shader_atomic_counter_ops),
-   EXT(ARB_shader_atomic_counters,       true,  false,     ARB_shader_atomic_counters),
-   EXT(ARB_shader_bit_encoding,          true,  false,     ARB_shader_bit_encoding),
-   EXT(ARB_shader_clock,                 true,  false,     ARB_shader_clock),
-   EXT(ARB_shader_draw_parameters,       true,  false,     ARB_shader_draw_parameters),
-   EXT(ARB_shader_group_vote,            true,  false,     ARB_shader_group_vote),
-   EXT(ARB_shader_image_load_store,      true,  false,     ARB_shader_image_load_store),
-   EXT(ARB_shader_image_size,            true,  false,     ARB_shader_image_size),
-   EXT(ARB_shader_precision,             true,  false,     ARB_shader_precision),
-   EXT(ARB_shader_stencil_export,        true,  false,     ARB_shader_stencil_export),
-   EXT(ARB_shader_storage_buffer_object, true,  true,      ARB_shader_storage_buffer_object),
-   EXT(ARB_shader_subroutine,            true,  false,     ARB_shader_subroutine),
-   EXT(ARB_shader_texture_image_samples, true,  false,     ARB_shader_texture_image_samples),
-   EXT(ARB_shader_texture_lod,           true,  false,     ARB_shader_texture_lod),
-   EXT(ARB_shading_language_420pack,     true,  false,     ARB_shading_language_420pack),
-   EXT(ARB_shading_language_packing,     true,  false,     ARB_shading_language_packing),
-   EXT(ARB_tessellation_shader,          true,  false,     ARB_tessellation_shader),
-   EXT(ARB_texture_cube_map_array,       true,  false,     ARB_texture_cube_map_array),
-   EXT(ARB_texture_gather,               true,  false,     ARB_texture_gather),
-   EXT(ARB_texture_multisample,          true,  false,     ARB_texture_multisample),
-   EXT(ARB_texture_query_levels,         true,  false,     ARB_texture_query_levels),
-   EXT(ARB_texture_query_lod,            true,  false,     ARB_texture_query_lod),
-   EXT(ARB_texture_rectangle,            true,  false,     dummy_true),
-   EXT(ARB_uniform_buffer_object,        true,  false,     ARB_uniform_buffer_object),
-   EXT(ARB_vertex_attrib_64bit,          true,  false,     ARB_vertex_attrib_64bit),
-   EXT(ARB_viewport_array,               true,  false,     ARB_viewport_array),
+   EXT(ARB_ES3_1_compatibility),
+   EXT(ARB_ES3_2_compatibility),
+   EXT(ARB_arrays_of_arrays),
+   EXT(ARB_compute_shader),
+   EXT(ARB_conservative_depth),
+   EXT(ARB_cull_distance),
+   EXT(ARB_derivative_control),
+   EXT(ARB_draw_buffers),
+   EXT(ARB_draw_instanced),
+   EXT(ARB_enhanced_layouts),
+   EXT(ARB_explicit_attrib_location),
+   EXT(ARB_explicit_uniform_location),
+   EXT(ARB_fragment_coord_conventions),
+   EXT(ARB_fragment_layer_viewport),
+   EXT(ARB_gpu_shader5),
+   EXT(ARB_gpu_shader_fp64),
+   EXT(ARB_sample_shading),
+   EXT(ARB_separate_shader_objects),
+   EXT(ARB_shader_atomic_counter_ops),
+   EXT(ARB_shader_atomic_counters),
+   EXT(ARB_shader_bit_encoding),
+   EXT(ARB_shader_clock),
+   EXT(ARB_shader_draw_parameters),
+   EXT(ARB_shader_group_vote),
+   EXT(ARB_shader_image_load_store),
+   EXT(ARB_shader_image_size),
+   EXT(ARB_shader_precision),
+   EXT(ARB_shader_stencil_export),
+   EXT(ARB_shader_storage_buffer_object),
+   EXT(ARB_shader_subroutine),
+   EXT(ARB_shader_texture_image_samples),
+   EXT(ARB_shader_texture_lod),
+   EXT(ARB_shading_language_420pack),
+   EXT(ARB_shading_language_packing),
+   EXT(ARB_tessellation_shader),
+   EXT(ARB_texture_cube_map_array),
+   EXT(ARB_texture_gather),
+   EXT(ARB_texture_multisample),
+   EXT(ARB_texture_query_levels),
+   EXT(ARB_texture_query_lod),
+   EXT(ARB_texture_rectangle),
+   EXT(ARB_uniform_buffer_object),
+   EXT(ARB_vertex_attrib_64bit),
+   EXT(ARB_viewport_array),
 
    /* KHR extensions go here, sorted alphabetically.
     */
 
    /* OES extensions go here, sorted alphabetically.
     */
-   EXT(OES_EGL_image_external,         false, true,      OES_EGL_image_external),
-   EXT(OES_geometry_point_size,        false, true,      OES_geometry_shader),
-   EXT(OES_geometry_shader,            false, true,      OES_geometry_shader),
-   EXT(OES_gpu_shader5,                false, true,      ARB_gpu_shader5),
-   EXT(OES_sample_variables,           false, true,      OES_sample_variables),
-   EXT(OES_shader_image_atomic,        false, true,      ARB_shader_image_load_store),
-   EXT(OES_shader_io_blocks,           false, true,      OES_shader_io_blocks),
-   EXT(OES_shader_multisample_interpolation, false, true, OES_sample_variables),
-   EXT(OES_standard_derivatives,       false, true,      OES_standard_derivatives),
-   EXT(OES_texture_3D,                 false, true,      dummy_true),
-   EXT(OES_texture_buffer,             false, true,      OES_texture_buffer),
-   EXT(OES_texture_storage_multisample_2d_array, false, true, ARB_texture_multisample),
+   EXT(OES_EGL_image_external),
+   EXT(OES_geometry_point_size),
+   EXT(OES_geometry_shader),
+   EXT(OES_gpu_shader5),
+   EXT(OES_sample_variables),
+   EXT(OES_shader_image_atomic),
+   EXT(OES_shader_io_blocks),
+   EXT(OES_shader_multisample_interpolation),
+   EXT(OES_standard_derivatives),
+   EXT(OES_texture_3D),
+   EXT(OES_texture_buffer),
+   EXT(OES_texture_storage_multisample_2d_array),
 
    /* All other extensions go here, sorted alphabetically.
     */
-   EXT(AMD_conservative_depth,         true,  false,     ARB_conservative_depth),
-   EXT(AMD_shader_stencil_export,      true,  false,     ARB_shader_stencil_export),
-   EXT(AMD_shader_trinary_minmax,      true,  false,     dummy_true),
-   EXT(AMD_vertex_shader_layer,        true,  false,     AMD_vertex_shader_layer),
-   EXT(AMD_vertex_shader_viewport_index, true,  false,   AMD_vertex_shader_viewport_index),
-   EXT(EXT_blend_func_extended,        false,  true,     ARB_blend_func_extended),
-   EXT(EXT_draw_buffers,               false,  true,     dummy_true),
-   EXT(EXT_clip_cull_distance,         false, true,      ARB_cull_distance),
-   EXT(EXT_gpu_shader5,                false, true,      ARB_gpu_shader5),
-   EXT(EXT_separate_shader_objects,    false, true,      dummy_true),
-   EXT(EXT_shader_integer_mix,         true,  true,      EXT_shader_integer_mix),
-   EXT(EXT_shader_io_blocks,           false, true,      OES_shader_io_blocks),
-   EXT(EXT_shader_samples_identical,   true,  true,      EXT_shader_samples_identical),
-   EXT(EXT_texture_array,              true,  false,     EXT_texture_array),
-   EXT(EXT_texture_buffer,             false, true,      OES_texture_buffer),
-   EXT(MESA_shader_integer_functions,  true,  true,      MESA_shader_integer_functions),
+   EXT(AMD_conservative_depth),
+   EXT(AMD_shader_stencil_export),
+   EXT(AMD_shader_trinary_minmax),
+   EXT(AMD_vertex_shader_layer),
+   EXT(AMD_vertex_shader_viewport_index),
+   EXT(EXT_blend_func_extended),
+   EXT(EXT_draw_buffers),
+   EXT(EXT_clip_cull_distance),
+   EXT(EXT_gpu_shader5),
+   EXT(EXT_separate_shader_objects),
+   EXT(EXT_shader_integer_mix),
+   EXT(EXT_shader_io_blocks),
+   EXT(EXT_shader_samples_identical),
+   EXT(EXT_texture_array),
+   EXT(EXT_texture_buffer),
+   EXT(MESA_shader_integer_functions),
 };
 
 #undef EXT
@@ -662,26 +665,10 @@ static const _mesa_glsl_extension _mesa_glsl_supported_extensions[] = {
  * Determine whether a given extension is compatible with the target,
  * API, and extension information in the current parser state.
  */
-bool _mesa_glsl_extension::compatible_with_state(const _mesa_glsl_parse_state *
-                                                 state) const
+bool _mesa_glsl_extension::compatible_with_state(
+      const _mesa_glsl_parse_state *state, gl_api api, uint8_t gl_version) const
 {
-   /* Check that this extension matches whether we are compiling
-    * for desktop GL or GLES.
-    */
-   if (state->es_shader) {
-      if (!this->avail_in_ES) return false;
-   } else {
-      if (!this->avail_in_GL) return false;
-   }
-
-   /* Check that this extension is supported by the OpenGL
-    * implementation.
-    *
-    * Note: the ->* operator indexes into state->extensions by the
-    * offset this->supported_flag.  See
-    * _mesa_glsl_extension::supported_flag for more info.
-    */
-   return state->extensions->*(this->supported_flag);
+   return this->available_pred(state->ctx, api, gl_version);
 }
 
 /**
@@ -719,6 +706,8 @@ _mesa_glsl_process_extension(const char *name, YYLTYPE *name_locp,
 			     const char *behavior_string, YYLTYPE *behavior_locp,
 			     _mesa_glsl_parse_state *state)
 {
+   uint8_t gl_version = state->ctx->Extensions.Version;
+   gl_api api = state->ctx->API;
    ext_behavior behavior;
    if (strcmp(behavior_string, "warn") == 0) {
       behavior = extension_warn;
@@ -735,6 +724,17 @@ _mesa_glsl_process_extension(const char *name, YYLTYPE *name_locp,
       return false;
    }
 
+   /* If we're in a desktop context but with an ES shader, use an ES API enum
+    * to verify extension availability.
+    */
+   if (state->es_shader && api != API_OPENGLES2)
+      api = API_OPENGLES2;
+   /* Use the language-version derived GL version to extension checks, unless
+    * we're using meta, which sets the version to the max.
+    */
+   if (gl_version != 0xff)
+      gl_version = state->gl_version;
+
    if (strcmp(name, "all") == 0) {
       if ((behavior == extension_enable) || (behavior == extension_require)) {
 	 _mesa_glsl_error(name_locp, state, "cannot %s all extensions",
@@ -746,14 +746,14 @@ _mesa_glsl_process_extension(const char *name, YYLTYPE *name_locp,
               i < ARRAY_SIZE(_mesa_glsl_supported_extensions); ++i) {
             const _mesa_glsl_extension *extension
                = &_mesa_glsl_supported_extensions[i];
-            if (extension->compatible_with_state(state)) {
+            if (extension->compatible_with_state(state, api, gl_version)) {
                _mesa_glsl_supported_extensions[i].set_flags(state, behavior);
             }
          }
       }
    } else {
       const _mesa_glsl_extension *extension = find_extension(name);
-      if (extension && extension->compatible_with_state(state)) {
+      if (extension && extension->compatible_with_state(state, api, gl_version)) {
          extension->set_flags(state, behavior);
       } else {
          static const char fmt[] = "extension `%s' unsupported in %s shader";
@@ -1790,6 +1790,43 @@ assign_subroutine_indexes(struct gl_shader *sh,
    }
 }
 
+static void
+add_builtin_defines(struct _mesa_glsl_parse_state *state,
+                    void (*add_builtin_define)(struct glcpp_parser *, const char *, int),
+                    struct glcpp_parser *data,
+                    unsigned version,
+                    bool es)
+{
+   unsigned gl_version = state->ctx->Extensions.Version;
+   gl_api api = state->ctx->API;
+
+   if (gl_version != 0xff) {
+      unsigned i;
+      for (i = 0; i < state->num_supported_versions; i++) {
+         if (state->supported_versions[i].ver == version &&
+             state->supported_versions[i].es == es) {
+            gl_version = state->supported_versions[i].gl_ver;
+            break;
+         }
+      }
+
+      if (i == state->num_supported_versions)
+         return;
+   }
+
+   if (es)
+      api = API_OPENGLES2;
+
+   for (unsigned i = 0;
+        i < ARRAY_SIZE(_mesa_glsl_supported_extensions); ++i) {
+      const _mesa_glsl_extension *extension
+         = &_mesa_glsl_supported_extensions[i];
+      if (extension->compatible_with_state(state, api, gl_version)) {
+         add_builtin_define(data, extension->name, 1);
+      }
+   }
+}
+
 void
 _mesa_glsl_compile_shader(struct gl_context *ctx, struct gl_shader *shader,
                           bool dump_ast, bool dump_hir)
@@ -1803,7 +1840,7 @@ _mesa_glsl_compile_shader(struct gl_context *ctx, struct gl_shader *shader,
                               false, true);
 
    state->error = glcpp_preprocess(state, &source, &state->info_log,
-                             &ctx->Extensions, ctx);
+                             add_builtin_defines, state, ctx);
 
    if (!state->error) {
      _mesa_glsl_lexer_ctor(state, source);