glsl: Add support for generating builtin code from GLSL instead of IR.

This takes advantage of the builtin compiler to generate IR into a
string, the same way we read GLSL for function prototypes for our
profiles.

Reviewed-by: Kenneth Graunke <kenneth@whitecape.org>

src/glsl/builtins/tools/generate_builtins.py

@@ -29,11 +29,23 @@ def read_ir_files(fs):
         with open(filename) as f:
             fs[function_name] = f.read()
 
+def read_glsl_files(fs):
+    for filename in glob(path.join(path.join(builtins_dir, 'glsl'), '*.glsl')):
+        function_name = path.basename(filename).split('.')[0]
+        (output, returncode) = run_compiler([filename])
+        if (returncode):
+            sys.stderr.write("Failed to compile builtin: " + filename + "\n")
+            sys.stderr.write("Result:\n")
+            sys.stderr.write(output)
+        else:
+            fs[function_name] = output;
+
 # Return a dictionary containing all builtin definitions (even generated)
 def get_builtin_definitions():
     fs = {}
     generate_texture_functions(fs)
     read_ir_files(fs)
+    read_glsl_files(fs)
     return fs
 
 def stringify(s):
@@ -78,6 +90,10 @@ def run_compiler(args):
     # Also toss any duplicate newlines
     output = output.replace('\n\n', '\n')
 
+    # Kill any global variable declarations.  We don't want them.
+    kill_globals = re.compile(r'^\(declare.*\n', re.MULTILINE)
+    output = kill_globals.sub('', output)
+
     return (output, p.returncode)
 
 def write_profile(filename, profile):
@@ -87,10 +103,6 @@ def write_profile(filename, profile):
         print '#error builtins profile', profile, 'failed to compile'
         return
 
-    # Kill any global variable declarations.  We don't want them.
-    kill_globals = re.compile(r'^\(declare.*\n', re.MULTILINE)
-    proto_ir = kill_globals.sub('', proto_ir)
-
     print 'static const char prototypes_for_' + profile + '[] ='
     print stringify(proto_ir), ';'