Issue #43 - Add -O0 to disable optimizations

This is the first step to being able to specify optimization level from the command line. This will be more important as more optimizations are added and when (if) some of them are not always safe to apply.

cyclone.scm

@@ -22,6 +22,8 @@
         (scheme cyclone macros)
         (scheme cyclone libraries))
 
+(define *optimization-level* 2) ;; Default level
+
 ;; Code emission.
   
 ; c-compile-and-emit : (string -> A) exp -> void
@@ -228,10 +230,11 @@
       (trace:info "---------------- after CPS:")
       (trace:info input-program) ;pretty-print
 
+      (when (> *optimization-level* 0)
         (set! input-program
           (optimize-cps input-program))
         (trace:info "---------------- after cps optimizations:")
-      (trace:info input-program)
+        (trace:info input-program))
     
       (set! input-program
         (map
@@ -380,6 +383,11 @@
                                (equal? #\- (string-ref arg 0)))))
                    args))
        (compile? #t))
+  ;; Set optimization level(s)
+  (if (member "-O0" args)
+      (set! *optimization-level* 0))
+  ;; TODO: place more optimization reading here as necessary
+  ;; End optimizations
   (if (member "-t" args)
       (set! *trace-level* 4)) ;; Show all trace output
   (if (member "-d" args)
@@ -392,6 +400,8 @@
  -d              Only generate intermediate C files, do not compile them
  -h, --help      Display usage information
  -v              Display version information
+ -Ox             Optimization level, higher means more optimizations will
+                 be used. Set to 0 to disable optimizations.
  --autogen       Cyclone developer use only, create autogen.out file
 ")
      (newline))