[COMPILER]

* OPT: Write in the bytecode file if a function uses the IsMissing() native 
  routine.

[INTERPRETER]
* OPT: Don't use a stack slot for missing arguments if the IsMissing() 
  function is not used.


git-svn-id: svn://localhost/gambas/trunk@6274 867c0c6c-44f3-4631-809d-bfa615b0a4ec

main/gbc/gbc_class.h

@@ -92,7 +92,8 @@ typedef
 		char npmin;                    // Minimum number of arguments
 		unsigned vararg : 1;           // If this function accepts extra arguments
 		unsigned fast : 1;             // If this function is jit compiled
-		unsigned _reserved : 14;
+		unsigned use_is_missing : 1;   // If this function uses IsMissing()
+		unsigned _reserved : 13;
 		short nlocal;                  // Local variable count
 		short nctrl;                   // Control structure variable count
 		

main/gbc/gbc_output.c

@@ -800,6 +800,7 @@ static void output_method(void)
 {
 	int i, n;
 	FUNCTION *func;
+	uchar flag;
 	/*SYMBOL *sym;*/
 
 	n = ARRAY_count(Class->function);
@@ -814,7 +815,13 @@ static void output_method(void)
 		write_byte(func->nparam);
 		write_byte(func->npmin);
 		write_byte(func->vararg);
-		write_byte(func->fast || Class->all_fast);
+
+		flag = func->fast || Class->all_fast;
+		if (func->use_is_missing)
+			flag += 2;
+
+		write_byte(flag);
+
 		write_short(func->nlocal);
 		write_short(func->nctrl);
 		write_short(func->stack);

main/gbc/gbc_trans_expr.c

@@ -271,6 +271,7 @@ static void trans_subr(int subr, short nparam)
 	}
 	else if (subr == SUBR_IsMissing)
 	{
+		JOB->func->use_is_missing = TRUE;
 		if (CODE_check_ismissing())
 			THROW("IsMissing() requires a function argument");
 	}

main/gbx/gbx_class.h

@@ -101,7 +101,8 @@ typedef
 		char vararg;
 		unsigned fast : 1;
 		unsigned optional : 1;
-		unsigned _reserved : 6;
+		unsigned use_is_missing : 1;
+		unsigned _reserved : 5;
 		short n_local;
 		short n_ctrl;
 		short stack_usage;
@@ -114,6 +115,17 @@ typedef
 	PACKED
 	FUNCTION;
 
+typedef
+	struct {
+		TYPE type;
+		char n_param;
+		char npmin;
+		char vararg;
+		unsigned char flag;
+		}
+	PACKED
+	FUNCTION_FLAG;
+
 typedef
 	struct {
 		TYPE type;

main/gbx/gbx_class_load.c

@@ -496,6 +496,7 @@ static void load_and_relocate(CLASS *class, int len_data, CLASS_DESC **pstart, i
 	char *name;
 	int len;
 	bool have_jit_functions = FALSE;
+	uchar flag;
 	
 	ALLOC_ZERO(&class->load, sizeof(CLASS_LOAD));
 
@@ -576,6 +577,13 @@ static void load_and_relocate(CLASS *class, int len_data, CLASS_DESC **pstart, i
 	{
 		func = &class->load->func[i];
 		func->code = (ushort *)get_section("code", &section, NULL, _s);
+
+		flag = ((FUNCTION_FLAG *)func)->flag;
+
+		func->fast = (flag & 1) != 0;
+		func->optional = (func->npmin < func->n_param);
+		func->use_is_missing = (flag & 2) != 0;
+
 		if (func->fast)
 		{
 			func->fast = JIT_load();
@@ -583,8 +591,7 @@ static void load_and_relocate(CLASS *class, int len_data, CLASS_DESC **pstart, i
 				have_jit_functions = TRUE;
 		}
 
-		func->optional = (func->npmin < func->n_param);
-		if (func->optional)
+		if (func->use_is_missing)
 		{
 			func->stack_usage++;
 			func->n_ctrl++;

main/gbx/gbx_class_load.h

@@ -109,7 +109,7 @@ typedef
     char n_param;
     char npmin;
     char vararg;
-    char _reserved;
+    char flag;
     short n_local;
     short n_ctrl;
     short stack_usage;

main/gbx/gbx_exec.c

@@ -542,7 +542,7 @@ void EXEC_enter(void)
 		}
 
 		// Optional argument map
-		if (optional)
+		if (optional && func->use_is_missing)
 		{
 			SP--;
 			SP->type = T_LONG;