allow no_optimize esp. for debugger

include/mruby/compile.h

@@ -29,6 +29,7 @@ typedef struct mrbc_context {
   mrb_bool dump_result:1;
   mrb_bool no_exec:1;
   mrb_bool keep_lv:1;
+  mrb_bool no_optimize:1;
 } mrbc_context;
 
 mrbc_context* mrbc_context_new(mrb_state *mrb);
@@ -143,6 +144,7 @@ struct mrb_parser_state {
   size_t nwarn;
   mrb_ast_node *tree;
 
+  mrb_bool no_optimize:1;
   mrb_bool capture_errors:1;
   struct mrb_parser_message error_buffer[10];
   struct mrb_parser_message warn_buffer[10];

src/codegen.c

@@ -162,11 +162,19 @@ genop(codegen_scope *s, mrb_code i)
 #define NOVAL  0
 #define VAL    1
 
+static mrb_bool
+no_optimize(codegen_scope *s)
+{
+  if (s && s->parser && s->parser->no_optimize)
+    return TRUE;
+  return FALSE;
+}
+
 static int
 genop_peep(codegen_scope *s, mrb_code i, int val)
 {
   /* peephole optimization */
-  if (s->lastlabel != s->pc && s->pc > 0) {
+  if (!no_optimize(s) && s->lastlabel != s->pc && s->pc > 0) {
     mrb_code i0 = s->iseq[s->pc-1];
     int c1 = GET_OPCODE(i);
     int c0 = GET_OPCODE(i0);

src/parse.y

@@ -5330,6 +5330,7 @@ parser_init_cxt(parser_state *p, mrbc_context *cxt)
     }
   }
   p->capture_errors = cxt->capture_errors;
+  p->no_optimize = cxt->no_optimize;
   if (cxt->partial_hook) {
     p->cxt = cxt;
   }