end block can not be optimized away any more.

[libfirm] / ir / ir / irflag.h

diff --git a/ir/ir/irflag.h b/ir/ir/irflag.h
index 5df905f..5303024 100644 (file)
--- a/ir/ir/irflag.h
+++ b/ir/ir/irflag.h
@@ -9,17 +9,34 @@
 #ifndef _IRFLAG_H_
 #define _IRFLAG_H_
 
-extern int opt_cse;
-extern int opt_constant_folding;
+/* If optimize == 0 no optimizations are performed.
+   Default: optimize == 1. */
+void set_optimize (int value);
+int  get_optimize (void);
 
-/* set the flags with set_flagname, get the flag with get_flagname */
+/* If opt_constant_folding == 1 perform
+    - constant expression evaluation (2 + 5 ==> 7, 3 < 2 ==> false)
+    - algebraic simplification  (a * 0 ==> 0, a or a ==> a)
+    - simplification of tests   ( !(a < b) ==> (a >= b))
+    - merging single exit with single entry blocks
+    - unreachable code elimination
+    - refining the memory representation
+    - remove store after load
+   Default: opt_constant_folding == 1. */
+void set_opt_constant_folding (int value);
+int  get_opt_constant_folding (void);
 
+/* If opt_cse == 1 perfor constant subexpression elimination
+   (and, if implemented, global code motion.  @@@ Right now
+   cse only within blocks.
+   Default: opt_cse == 1. */
 void set_opt_cse (int value);
 int  get_opt_cse (void);
-void set_opt_constant_folding (int value);
-int  get_opt_constant_folding (void);
 
-void set_optimize (int value);
-int  get_optimize (void);
+/* If opt_dead_node_elimination == 1 deallocate all dead nodes
+   by copying the firm graph.
+   Default: opt_dead_node_elimination == 0.  @@@ as buggy, else 1. */
+void set_opt_dead_node_elimination (int value);
+int  get_opt_dead_node_elimination (void);
 
 #endif