diff --git a/ChangeLog b/ChangeLog
index c0b37a5d47..fcbbade408 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,12 @@
+Thu Jul  5 19:45:55 2007  Koichi Sasada  <ko1@atdot.net>
+
+	* yarvcore.h: rename rb_control_frame_t#magic to flag.
+
+	* vm.h: add VM_FRAME_TYPE() and VM_FRAME_FLAG().
+
+	* cont.c, insnhelper.ci, insns.def, vm.c, vm_dump.c,
+	  vm_evalbody.ci, yarvcore.c: apply above changes.
+
 Thu Jul  5 19:16:14 2007  Koichi Sasada  <ko1@atdot.net>
 
 	* test/ruby/test_basicinstructions.rb: remove an assertion using
diff --git a/cont.c b/cont.c
index 833182aa4e..3a7f7ee235 100644
--- a/cont.c
+++ b/cont.c
@@ -489,7 +489,7 @@ rb_fiber_s_new(VALUE self)
     *th->cfp->lfp = 0;
     th->cfp->dfp = th->stack;
     th->cfp->self = Qnil;
-    th->cfp->magic = 0;
+    th->cfp->flag = 0;
     th->cfp->iseq = 0;
     th->cfp->proc = 0;
     th->cfp->block_iseq = 0;
diff --git a/insnhelper.ci b/insnhelper.ci
index 73ea6ee09a..f3665be14f 100644
--- a/insnhelper.ci
+++ b/insnhelper.ci
@@ -17,7 +17,7 @@
 /* control stack frame */
 
 static inline rb_control_frame_t *
-vm_push_frame(rb_thread_t *th, rb_iseq_t *iseq, VALUE magic,
+vm_push_frame(rb_thread_t *th, rb_iseq_t *iseq, VALUE type,
 	      VALUE self, VALUE specval, VALUE *pc,
 	      VALUE *sp, VALUE *lfp, int local_size)
 {
@@ -44,7 +44,7 @@ vm_push_frame(rb_thread_t *th, rb_iseq_t *iseq, VALUE magic,
     cfp->sp = sp + 1;
     cfp->bp = sp + 1;
     cfp->iseq = iseq;
-    cfp->magic = magic;
+    cfp->flag = VM_FRAME_FLAG(type);
     cfp->self = self;
     cfp->lfp = lfp;
     cfp->dfp = dfp;
diff --git a/insns.def b/insns.def
index 471f2a5bfb..63f1ca1153 100644
--- a/insns.def
+++ b/insns.def
@@ -1406,7 +1406,7 @@ throw
 		    rb_bug("VM (throw): can't find break base.");
 		}
 
-		if (cfp->magic == FRAME_MAGIC_LAMBDA) {
+		if (VM_FRAME_TYPE(cfp) == FRAME_MAGIC_LAMBDA) {
 		    /* lambda{... break ...} */
 		    is_orphan = 0;
 		    pt = dfp;
@@ -1465,7 +1465,7 @@ throw
 		 */
 		while ((VALUE *) cfp < th->stack + th->stack_size) {
 		    if (GET_DFP() == dfp) {
-			if (cfp->magic == FRAME_MAGIC_LAMBDA) {
+			if (VM_FRAME_TYPE(cfp) == FRAME_MAGIC_LAMBDA) {
 			    /* in lambda */
 			    is_orphan = 0;
 			    break;
diff --git a/vm.c b/vm.c
index fd7bd4f372..736494fe86 100644
--- a/vm.c
+++ b/vm.c
@@ -547,7 +547,7 @@ invoke_block(rb_thread_t *th, rb_block_t *block, VALUE self, int argc, VALUE *ar
     if (BUILTIN_TYPE(block->iseq) != T_NODE) {
 	rb_iseq_t *iseq = block->iseq;
 	int i, opt_pc;
-	int magic = block_proc_is_lambda(block->proc) ?
+	int type = block_proc_is_lambda(block->proc) ?
 	  FRAME_MAGIC_LAMBDA : FRAME_MAGIC_BLOCK;
 
 	rb_vm_set_finish_env(th);
@@ -559,11 +559,11 @@ invoke_block(rb_thread_t *th, rb_block_t *block, VALUE self, int argc, VALUE *ar
 	    th->cfp->sp[i] = argv[i];
 	}
 
-	opt_pc = vm_yield_setup_args(th, iseq, argc, th->cfp->sp, magic == FRAME_MAGIC_LAMBDA);
+	opt_pc = vm_yield_setup_args(th, iseq, argc, th->cfp->sp, type == FRAME_MAGIC_LAMBDA);
 	argc = iseq->arg_size;
 	th->cfp->sp += argc;
 
-	vm_push_frame(th, iseq, magic,
+	vm_push_frame(th, iseq, type,
 		      self, GC_GUARDED_PTR(block->dfp),
 		      iseq->iseq_encoded + opt_pc, th->cfp->sp, block->lfp,
 		      iseq->local_size - argc);
@@ -783,7 +783,7 @@ check_svar(void)
     rb_thread_t *th = GET_THREAD();
     rb_control_frame_t *cfp = th->cfp;
     while ((void *)(cfp + 1) < (void *)(th->stack + th->stack_size)) {
-	/* printf("cfp: %p\n", cfp->magic); */
+	/* printf("cfp: %p\n", cfp->type); */
 	if (cfp->lfp && cfp->lfp[-1] != Qnil &&
 	    TYPE(cfp->lfp[-1]) != T_VALUES) {
 	    /* dp(cfp->lfp[-1]); */
@@ -1050,12 +1050,12 @@ yarv_init_redefined_flag(void)
     VALUE *pc;                  // cfp[0]
     VALUE *sp;                  // cfp[1]
     VALUE *bp;                  // cfp[2]
-    rb_iseq_t *iseq;          // cfp[3]
-    VALUE magic;                // cfp[4]
+    rb_iseq_t *iseq;            // cfp[3]
+    VALUE flag;                 // cfp[4]
     VALUE self;                 // cfp[5]
     VALUE *lfp;                 // cfp[6]
     VALUE *dfp;                 // cfp[7]
-    rb_iseq_t * block_iseq;   // cfp[8]
+    rb_iseq_t * block_iseq;     // cfp[8]
     VALUE proc;                 // cfp[9] always 0
   };
 
diff --git a/vm.h b/vm.h
index ae1f162c95..de8365b411 100644
--- a/vm.h
+++ b/vm.h
@@ -231,26 +231,25 @@ while (0)
   (!((th)->stack < (env) && (env) < ((th)->stack + (th)->stack_size)))
 #define ENV_VAL(env)        ((env)[1])
 
-#define FRAME_MAGIC_METHOD 0xfaffff11
-#define FRAME_MAGIC_BLOCK  0xfaffff21
-#define FRAME_MAGIC_CLASS  0xfaffff31
-#define FRAME_MAGIC_TOP    0xfaffff41
-#define FRAME_MAGIC_FINISH 0xfaffff51
-#define FRAME_MAGIC_CFUNC  0xfaffff61
-#define FRAME_MAGIC_PROC   0xfaffff71
-#define FRAME_MAGIC_IFUNC  0xfaffff81
-#define FRAME_MAGIC_EVAL   0xfaffff91
-#define FRAME_MAGIC_LAMBDA 0xfaffffa1
+#define FRAME_MAGIC_METHOD 0x11
+#define FRAME_MAGIC_BLOCK  0x21
+#define FRAME_MAGIC_CLASS  0x31
+#define FRAME_MAGIC_TOP    0x41
+#define FRAME_MAGIC_FINISH 0x51
+#define FRAME_MAGIC_CFUNC  0x61
+#define FRAME_MAGIC_PROC   0x71
+#define FRAME_MAGIC_IFUNC  0x81
+#define FRAME_MAGIC_EVAL   0x91
+#define FRAME_MAGIC_LAMBDA 0xa1
+#define FRAME_MAGIC_MASK   0xff
 
-#define CHECK_FRAME_MAGIC(magic)                   \
-{                                                  \
-  if((magic & 0xffffff00) != 0xfaffff00){          \
-    rb_bug("YARV Stack frame error: %08x", magic); \
-  }                                                \
-}
+#define VM_FRAME_FLAG(type) ((VALUE)((type) & FRAME_MAGIC_MASK))
+
+#define VM_FRAME_TYPE(cfp) \
+  ((cfp)->flag & FRAME_MAGIC_MASK)
 
 #define RUBYVM_CFUNC_FRAME_P(cfp) \
-  ((cfp)->magic == FRAME_MAGIC_CFUNC)
+  (VM_FRAME_TYPE(cfp) == FRAME_MAGIC_CFUNC)
 
 /*
  * Excception
diff --git a/vm_dump.c b/vm_dump.c
index 76b63bd203..c72b4e1e7e 100644
--- a/vm_dump.c
+++ b/vm_dump.c
@@ -46,7 +46,7 @@ control_frame_dump(rb_thread_t *th, rb_control_frame_t *cfp)
 	bp = cfp->bp - th->stack;
     }
 
-    switch (cfp->magic) {
+    switch (VM_FRAME_TYPE(cfp)) {
       case FRAME_MAGIC_TOP:
 	magic = "TOP";
 	break;
@@ -263,15 +263,15 @@ stack_dump_each(rb_thread_t *th, rb_control_frame_t *cfp)
 
     /* stack trace header */
 
-    if (cfp->magic == FRAME_MAGIC_METHOD ||
-	cfp->magic == FRAME_MAGIC_TOP ||
-	cfp->magic == FRAME_MAGIC_BLOCK ||
-	cfp->magic == FRAME_MAGIC_CLASS ||
-	cfp->magic == FRAME_MAGIC_PROC ||
-	cfp->magic == FRAME_MAGIC_LAMBDA ||
-	cfp->magic == FRAME_MAGIC_CFUNC ||
-	cfp->magic == FRAME_MAGIC_IFUNC ||
-	cfp->magic == FRAME_MAGIC_EVAL) {
+    if (VM_FRAME_TYPE(cfp) == FRAME_MAGIC_METHOD ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_TOP ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_BLOCK ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_CLASS ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_PROC ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_LAMBDA ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_CFUNC ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_IFUNC ||
+	VM_FRAME_TYPE(cfp) == FRAME_MAGIC_EVAL) {
 
 	VALUE *ptr = dfp - local_size;
 
@@ -304,7 +304,7 @@ stack_dump_each(rb_thread_t *th, rb_control_frame_t *cfp)
 		   ptr - th->stack);
 	}
     }
-    else if (cfp->magic == FRAME_MAGIC_FINISH) {
+    else if (VM_FRAME_TYPE(cfp) == FRAME_MAGIC_FINISH) {
 	if ((th)->stack + (th)->stack_size > (VALUE *)(cfp + 2)) {
 	    stack_dump_each(th, cfp + 1);
 	}
@@ -313,7 +313,7 @@ stack_dump_each(rb_thread_t *th, rb_control_frame_t *cfp)
 	}
     }
     else {
-	rb_bug("unsupport frame type: %08lx", cfp->magic);
+	rb_bug("unsupport frame type: %08lx", VM_FRAME_TYPE(cfp));
     }
 }
 
@@ -354,7 +354,7 @@ debug_print_pre(rb_thread_t *th, rb_control_frame_t *cfp)
 {
     rb_iseq_t *iseq = cfp->iseq;
 
-    if (iseq != 0 && cfp->magic != FRAME_MAGIC_FINISH) {
+    if (iseq != 0 && VM_FRAME_TYPE(cfp) != FRAME_MAGIC_FINISH) {
 	VALUE *seq = iseq->iseq;
 	int pc = cfp->pc - iseq->iseq_encoded;
 
diff --git a/vm_evalbody.ci b/vm_evalbody.ci
index 2e8746813a..f9dd39f5a3 100644
--- a/vm_evalbody.ci
+++ b/vm_evalbody.ci
@@ -134,7 +134,7 @@ vm_eval(rb_thread_t *th, VALUE initial)
 	}
     }
 
-    if (th->cfp->magic != FRAME_MAGIC_FINISH) {
+    if (VM_FRAME_TYPE(th->cfp) != FRAME_MAGIC_FINISH) {
 	rb_bug("cfp consistency error");
     }
 
diff --git a/yarvcore.c b/yarvcore.c
index b25de4afc4..72755198d8 100644
--- a/yarvcore.c
+++ b/yarvcore.c
@@ -340,7 +340,7 @@ th_init2(rb_thread_t *th)
     *th->cfp->lfp = 0;
     th->cfp->dfp = th->stack;
     th->cfp->self = Qnil;
-    th->cfp->magic = 0;
+    th->cfp->flag = 0;
     th->cfp->iseq = 0;
     th->cfp->proc = 0;
     th->cfp->block_iseq = 0;
diff --git a/yarvcore.h b/yarvcore.h
index 149a57fd10..4931900848 100644
--- a/yarvcore.h
+++ b/yarvcore.h
@@ -387,7 +387,7 @@ typedef struct {
     VALUE *sp;			/* cfp[1] */
     VALUE *bp;			/* cfp[2] */
     rb_iseq_t *iseq;		/* cfp[3] */
-    VALUE magic;		/* cfp[4] */
+    VALUE flag;			/* cfp[4] */
     VALUE self;			/* cfp[5] / block[0] */
     VALUE *lfp;			/* cfp[6] / block[1] */
     VALUE *dfp;			/* cfp[7] / block[2] */