glsl: Make a function to express a GLSL version ir human-readable form.

This will be useful in generating more helpful error messages,
especially with the addition of GLSL 3.00 ES support.

[v2, idr]: Rename ctx parameter to mem_ctx

Signed-off-by: Ian Romanick <ian.d.romanick@intel.com>
Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>
Acked-by: Carl Worth <cworth@cworth.org>

src/glsl/glsl_parser.yy

@@ -290,10 +290,8 @@ version_statement:
 
 	   state->language_version = $2;
 	   state->version_string =
-	      ralloc_asprintf(state, "GLSL%s %d.%02d",
-			      state->es_shader ? " ES" : "",
-			      state->language_version / 100,
-			      state->language_version % 100);
+              glsl_compute_version_string(state, state->es_shader,
+                                          state->language_version);
 
 	   if (!supported) {
 	      _mesa_glsl_error(& @2, state, "%s is not supported. "

src/glsl/glsl_parser_extras.cpp

@@ -37,6 +37,16 @@ extern "C" {
 #include "ir_optimization.h"
 #include "loop_analysis.h"
 
+/**
+ * Format a short human-readable description of the given GLSL version.
+ */
+const char *
+glsl_compute_version_string(void *mem_ctx, bool is_es, unsigned version)
+{
+   return ralloc_asprintf(mem_ctx, "GLSL%s %d.%02d", is_es ? " ES" : "",
+                          version / 100, version % 100);
+}
+
 _mesa_glsl_parse_state::_mesa_glsl_parse_state(struct gl_context *_ctx,
 					       GLenum target, void *mem_ctx)
  : ctx(_ctx)

src/glsl/glsl_parser_extras.h

@@ -56,6 +56,9 @@ struct glsl_switch_state {
    bool is_switch_innermost; // if switch stmt is closest to break, ...
 };
 
+const char *
+glsl_compute_version_string(void *mem_ctx, bool is_es, unsigned version);
+
 struct _mesa_glsl_parse_state {
    _mesa_glsl_parse_state(struct gl_context *_ctx, GLenum target,
 			  void *mem_ctx);