glsl: process blend_support_* qualifiers

v2 (Ken): Add a BLEND_NONE enum value (no qualifiers in use).
v3 (Ken): Rename gl_blend_support_qualifier to gl_advanced_blend_mode.
v4 (Ken): Mark map[] as static const (Ilia).

Signed-off-by: Ilia Mirkin <imirkin@alum.mit.edu>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Reviewed-by: Francisco Jerez <currojerez@riseup.net>

src/compiler/glsl/ast.h

@@ -596,6 +596,11 @@ struct ast_type_qualifier {
          unsigned subroutine:1;  /**< Is this marked 'subroutine' */
          unsigned subroutine_def:1; /**< Is this marked 'subroutine' with a list of types */
 	 /** \} */
+
+         /** \name Qualifiers for GL_KHR_blend_equation_advanced */
+         /** \{ */
+         unsigned blend_support:1; /**< Are there any blend_support_ qualifiers */
+         /** \} */
       }
       /** \brief Set of flags, accessed by name. */
       q;

src/compiler/glsl/ast_type.cpp

@@ -414,6 +414,8 @@ ast_type_qualifier::merge_out_qualifier(YYLTYPE *loc,
       valid_out_mask.flags.q.xfb_buffer = 1;
       valid_out_mask.flags.q.explicit_xfb_stride = 1;
       valid_out_mask.flags.q.xfb_stride = 1;
+   } else if (state->stage == MESA_SHADER_FRAGMENT) {
+      valid_out_mask.flags.q.blend_support = 1;
    } else {
       _mesa_glsl_error(loc, state, "out layout qualifiers only valid in "
                        "geometry, tessellation and vertex shaders");

src/compiler/glsl/glsl_parser.yy

@@ -1446,6 +1446,51 @@ layout_qualifier_id:
          }
       }
 
+      if (!$$.flags.i) {
+         static const struct {
+            const char *s;
+            uint32_t mask;
+         } map[] = {
+                 { "blend_support_multiply",       BLEND_MULTIPLY },
+                 { "blend_support_screen",         BLEND_SCREEN },
+                 { "blend_support_overlay",        BLEND_OVERLAY },
+                 { "blend_support_darken",         BLEND_DARKEN },
+                 { "blend_support_lighten",        BLEND_LIGHTEN },
+                 { "blend_support_colordodge",     BLEND_COLORDODGE },
+                 { "blend_support_colorburn",      BLEND_COLORBURN },
+                 { "blend_support_hardlight",      BLEND_HARDLIGHT },
+                 { "blend_support_softlight",      BLEND_SOFTLIGHT },
+                 { "blend_support_difference",     BLEND_DIFFERENCE },
+                 { "blend_support_exclusion",      BLEND_EXCLUSION },
+                 { "blend_support_hsl_hue",        BLEND_HSL_HUE },
+                 { "blend_support_hsl_saturation", BLEND_HSL_SATURATION },
+                 { "blend_support_hsl_color",      BLEND_HSL_COLOR },
+                 { "blend_support_hsl_luminosity", BLEND_HSL_LUMINOSITY },
+                 { "blend_support_all_equations",  BLEND_ALL },
+         };
+         for (unsigned i = 0; i < ARRAY_SIZE(map); i++) {
+            if (match_layout_qualifier($1, map[i].s, state) == 0) {
+               $$.flags.q.blend_support = 1;
+               state->fs_blend_support |= map[i].mask;
+               break;
+            }
+         }
+
+         if ($$.flags.i &&
+             !state->KHR_blend_equation_advanced_enable &&
+             !state->is_version(0, 320)) {
+            _mesa_glsl_error(& @1, state,
+                             "advanced blending layout qualifiers require "
+                             "ESSL 3.20 or KHR_blend_equation_advanced");
+         }
+
+         if ($$.flags.i && state->stage != MESA_SHADER_FRAGMENT) {
+            _mesa_glsl_error(& @1, state,
+                             "advanced blending layout qualifiers only "
+                             "valid in fragment shaders");
+         }
+      }
+
       if (!$$.flags.i) {
          _mesa_glsl_error(& @1, state, "unrecognized layout identifier "
                           "`%s'", $1);

src/compiler/glsl/glsl_parser_extras.cpp

@@ -292,6 +292,7 @@ _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
    this->in_qualifier = new(this) ast_type_qualifier();
    this->out_qualifier = new(this) ast_type_qualifier();
    this->fs_early_fragment_tests = false;
+   this->fs_blend_support = 0;
    memset(this->atomic_counter_offsets, 0,
           sizeof(this->atomic_counter_offsets));
    this->allow_extension_directive_midshader =
@@ -1765,6 +1766,7 @@ set_shader_inout_layout(struct gl_shader *shader,
       shader->info.ARB_fragment_coord_conventions_enable =
          state->ARB_fragment_coord_conventions_enable;
       shader->info.EarlyFragmentTests = state->fs_early_fragment_tests;
+      shader->info.BlendSupport = state->fs_blend_support;
       break;
 
    default:

src/compiler/glsl/glsl_parser_extras.h

@@ -746,6 +746,8 @@ struct _mesa_glsl_parse_state {
 
    bool fs_early_fragment_tests;
 
+   unsigned fs_blend_support;
+
    /**
     * For tessellation control shaders, size of the most recently seen output
     * declaration that was a sized array, or 0 if no sized output array

src/compiler/shader_enums.h

@@ -559,6 +559,32 @@ enum gl_buffer_access_qualifier
    ACCESS_VOLATILE = 4,
 };
 
+/**
+ * \brief Blend support qualifiers
+ */
+enum gl_advanced_blend_mode
+{
+   BLEND_NONE           = 0x0000,
+
+   BLEND_MULTIPLY       = 0x0001,
+   BLEND_SCREEN         = 0x0002,
+   BLEND_OVERLAY        = 0x0004,
+   BLEND_DARKEN         = 0x0008,
+   BLEND_LIGHTEN        = 0x0010,
+   BLEND_COLORDODGE     = 0x0020,
+   BLEND_COLORBURN      = 0x0040,
+   BLEND_HARDLIGHT      = 0x0080,
+   BLEND_SOFTLIGHT      = 0x0100,
+   BLEND_DIFFERENCE     = 0x0200,
+   BLEND_EXCLUSION      = 0x0400,
+   BLEND_HSL_HUE        = 0x0800,
+   BLEND_HSL_SATURATION = 0x1000,
+   BLEND_HSL_COLOR      = 0x2000,
+   BLEND_HSL_LUMINOSITY = 0x4000,
+
+   BLEND_ALL            = 0x7fff,
+};
+
 #ifdef __cplusplus
 } /* extern "C" */
 #endif

src/mesa/main/mtypes.h

@@ -2318,6 +2318,11 @@ struct gl_shader_info
     */
    bool EarlyFragmentTests;
 
+   /**
+    * A bitmask of gl_advanced_blend_mode values
+    */
+   GLbitfield BlendSupport;
+
    /**
     * Compute shader state from ARB_compute_shader layout qualifiers.
     */