glsl: Parse shared keyword for compute shader variables

v2:
 * Move shared parsing under storage qualifiers (tarceri)
 * Fail to compile if shared is used in non-compute shader (tarceri)
 * Use separate shared_storage bit for shared variables (tarceri)

Signed-off-by: Jordan Justen <jordan.l.justen@intel.com>
Reviewed-by: Timothy Arceri <timothy.arceri@collabora.com>

src/glsl/ast.h

@@ -448,6 +448,7 @@ struct ast_type_qualifier {
 	 unsigned patch:1;
 	 unsigned uniform:1;
 	 unsigned buffer:1;
+	 unsigned shared_storage:1;
 	 unsigned smooth:1;
 	 unsigned flat:1;
 	 unsigned noperspective:1;

src/glsl/ast_to_hir.cpp

@@ -3089,6 +3089,12 @@ apply_type_qualifier_to_variable(const struct ast_type_qualifier *qual,
                        "members");
    }
 
+   if (qual->flags.q.shared_storage && state->stage != MESA_SHADER_COMPUTE) {
+      _mesa_glsl_error(loc, state,
+                       "the shared storage qualifiers can only be used with "
+                       "compute shaders");
+   }
+
    if (qual->flags.q.row_major || qual->flags.q.column_major) {
       validate_matrix_layout_for_type(state, loc, var->type, var);
    }

src/glsl/ast_type.cpp

@@ -85,7 +85,8 @@ ast_type_qualifier::has_storage() const
           || this->flags.q.in
           || this->flags.q.out
           || this->flags.q.uniform
-          || this->flags.q.buffer;
+          || this->flags.q.buffer
+          || this->flags.q.shared_storage;
 }
 
 bool

src/glsl/glsl_lexer.ll

@@ -414,6 +414,8 @@ writeonly      KEYWORD_WITH_ALT(420, 300, 420, 310, yyextra->ARB_shader_image_lo
 
 atomic_uint     KEYWORD_WITH_ALT(420, 300, 420, 310, yyextra->ARB_shader_atomic_counters_enable, ATOMIC_UINT);
 
+shared          KEYWORD_WITH_ALT(430, 310, 430, 310, yyextra->ARB_compute_shader_enable, SHARED);
+
 struct		return STRUCT;
 void		return VOID_TOK;
 

src/glsl/glsl_parser.yy

@@ -165,6 +165,7 @@ static bool match_layout_qualifier(const char *s1, const char *s2,
 %token IMAGE1DSHADOW IMAGE2DSHADOW IMAGE1DARRAYSHADOW IMAGE2DARRAYSHADOW
 %token COHERENT VOLATILE RESTRICT READONLY WRITEONLY
 %token ATOMIC_UINT
+%token SHARED
 %token STRUCT VOID_TOK WHILE
 %token <identifier> IDENTIFIER TYPE_IDENTIFIER NEW_IDENTIFIER
 %type <identifier> any_identifier
@@ -1929,6 +1930,11 @@ storage_qualifier:
       memset(& $$, 0, sizeof($$));
       $$.flags.q.buffer = 1;
    }
+   | SHARED
+   {
+      memset(& $$, 0, sizeof($$));
+      $$.flags.q.shared_storage = 1;
+   }
    ;
 
 memory_qualifier: