Save input values beforehand. Clean up and refactor spill code.

ChangeLog

@@ -1,3 +1,14 @@
+2006-05-19  Aleksey Demakov  <ademakov@gmail.com>
+
+	* jit-reg-alloc.h, jit/jit-reg-alloc.c: determine if input values
+	need to be saved and evicted from registers to stack frame at the
+	_jit_regs_assign() time. Uniformly save input values that need to
+	in _jit_regs_gen(), do not save them in _jit_regs_commit(). This
+	simplifies handling of stack registers. Remove initial_stack_top,
+	exchanges, num_exchages fields from the _jit_regs_t struct. Add
+	save and kill bit fields to the _jit_regdesc_t struct. Refactor
+	and clean up code.
+
 2006-05-10  Aleksey Demakov  <ademakov@gmail.com>
 
 	* jit/jit-reg-alloc.c (use_cheapest_register): check if the other

jit/jit-reg-alloc.h

@@ -120,8 +120,10 @@ typedef struct
 	unsigned	clobber : 1;
 	unsigned	early_clobber : 1;
 	unsigned	duplicate : 1;
+	unsigned	save : 1;
 	unsigned	load : 1;
 	unsigned	copy : 1;
+	unsigned	kill : 1;
 
 } _jit_regdesc_t;
 
@@ -162,12 +164,9 @@ typedef struct
 	jit_regused_t	spill;
 
 	int		stack_start;
-	int		initial_stack_top;
 	int		current_stack_top;
 	int		wanted_stack_count;
 	int		loaded_stack_count;
-	int		exchanges[_JIT_REGS_MAX_EXCHANGES][2];
-	int		num_exchanges;
 } _jit_regs_t;
 
 void _jit_regs_init(_jit_regs_t *regs, int flags);