glsl: add ast/parser support for subroutine parsing storage (v3.2)

This is the guts of the GLSL parser and AST support for
shader subroutines.

The code creates a subroutine type in the parser, and
uses that there to validate the identifiers. The parser
also distinguishes between subroutine types/function prototypes
/uniforms and subroutine defintions for functions.

Then in the AST conversion it recreates the types, and
stores the subroutine definition info or subroutine info
into the ir_function along with a side lookup table in
the parser state. It also converts subroutine calls into
the enhanced ir_call.

v2: move to handling method calls in
function handling not in field selection.
v3: merge Chris's previous parser patches in here, to
make it clearer what's changed in one place.
v3.1: add more documentation, drop unused include
v3.2: drop is_subroutine_def

Reviewed-by: Chris Forbes <[email protected]>
Signed-off-by: Dave Airlie <[email protected]>

1 files changed, 19 insertions, 0 deletions

diff --git a/src/glsl/glsl_parser_extras.h b/src/glsl/glsl_parser_extras.h
index 564820183f5..b65d53db641 100644
--- a/src/glsl/glsl_parser_extras.h
+++ b/src/glsl/glsl_parser_extras.h
@@ -589,6 +589,25 @@ struct _mesa_glsl_parse_state {
    unsigned atomic_counter_offsets[MAX_COMBINED_ATOMIC_BUFFERS];
 
    bool allow_extension_directive_midshader;
+
+   /**
+    * Known subroutine type declarations.
+    */
+   int num_subroutine_types;
+   ir_function **subroutine_types;
+
+   /**
+    * Functions that are associated with
+    * subroutine types.
+    */
+   int num_subroutines;
+   ir_function **subroutines;
+
+   /**
+    * field selection temporary parser storage -
+    * did the parser just parse a dot.
+    */
+   bool is_field;
 };
 
 # define YYLLOC_DEFAULT(Current, Rhs, N)			\