Simplify `mrb_value` structure for `MRB_WORD_BOXING`.

include/mruby/boxing_word.h

@@ -47,13 +47,13 @@ enum mrb_special_consts {
 #define BOXWORD_IMMEDIATE_MASK  0x07
 
 #define BOXWORD_SHIFT_VALUE(o,n,t) \
-  (t)(((long)(o).w) >> BOXWORD_##n##_SHIFT)
+  (t)(((long)(o)) >> BOXWORD_##n##_SHIFT)
 #define BOXWORD_SET_SHIFT_VALUE(o,n,v) \
-  ((o).w = (((unsigned long)(v)) << BOXWORD_##n##_SHIFT) | BOXWORD_##n##_FLAG)
+  ((o) = (((unsigned long)(v)) << BOXWORD_##n##_SHIFT) | BOXWORD_##n##_FLAG)
 #define BOXWORD_SHIFT_VALUE_P(o,n) \
-  (((o).w & BOXWORD_##n##_MASK) == BOXWORD_##n##_FLAG)
+  (((o) & BOXWORD_##n##_MASK) == BOXWORD_##n##_FLAG)
 #define BOXWORD_OBJ_TYPE_P(o,n) \
-  (!mrb_immediate_p(o) && (o).value.bp->tt == MRB_TT_##n)
+  (!mrb_immediate_p(o) && mrb_val_union(o).bp->tt == MRB_TT_##n)
 
 /*
  * mrb_value representation:
@@ -67,56 +67,63 @@ enum mrb_special_consts {
  *   symbol: ...SSSS SS10 (use only upper 32-bit as symbol value on 64-bit CPU)
  *   object: ...PPPP P000 (any bits are 1)
  */
-typedef union mrb_value {
-  union {
-    void *p;
+typedef uintptr_t mrb_value;
+union mrb_value {
+  void *p;
 #ifdef MRB_64BIT
-    /* use struct to avoid bit shift. */
-    struct {
-      MRB_ENDIAN_LOHI(
-        mrb_sym sym;
-        ,uint32_t sym_flag;
-      )
-    };
+  /* use struct to avoid bit shift. */
+  struct {
+    MRB_ENDIAN_LOHI(
+      mrb_sym sym;
+      ,uint32_t sym_flag;
+    )
+  };
 #endif
-    struct RBasic *bp;
+  struct RBasic *bp;
 #ifndef MRB_WITHOUT_FLOAT
-    struct RFloat *fp;
+  struct RFloat *fp;
 #endif
-    struct RCptr *vp;
-  } value;
-  unsigned long w;
-} mrb_value;
+  struct RCptr *vp;
+  uintptr_t w;
+};
+
+static inline union mrb_value
+mrb_val_union(mrb_value v)
+{
+  union mrb_value x;
+  x.w = v;
+  return x;
+}
 
 MRB_API mrb_value mrb_word_boxing_cptr_value(struct mrb_state*, void*);
 #ifndef MRB_WITHOUT_FLOAT
 MRB_API mrb_value mrb_word_boxing_float_value(struct mrb_state*, mrb_float);
 #endif
 
-#define mrb_ptr(o)     (o).value.p
-#define mrb_cptr(o)    (o).value.vp->p
+#define mrb_ptr(o)     mrb_val_union(o).p
+#define mrb_cptr(o)    mrb_val_union(o).vp->p
 #ifndef MRB_WITHOUT_FLOAT
-#define mrb_float(o)   (o).value.fp->f
+#define mrb_float(o)   mrb_val_union(o).fp->f
 #endif
 #define mrb_fixnum(o)  BOXWORD_SHIFT_VALUE(o, FIXNUM, mrb_int)
 #ifdef MRB_64BIT
-#define mrb_symbol(o)  (o).value.sym
+#define mrb_symbol(o)  mrb_val_union(o).sym
 #else
 #define mrb_symbol(o)  BOXWORD_SHIFT_VALUE(o, SYMBOL, mrb_sym)
 #endif
-#define mrb_bool(o)    (((o).w & ~(unsigned long)MRB_Qfalse) != 0)
+#define mrb_bool(o)    (((o) & ~(unsigned long)MRB_Qfalse) != 0)
 
-#define mrb_immediate_p(o) ((o).w & BOXWORD_IMMEDIATE_MASK || (o).w == MRB_Qnil)
+#define mrb_immediate_p(o) ((o) & BOXWORD_IMMEDIATE_MASK || (o) == MRB_Qnil)
 #define mrb_fixnum_p(o) BOXWORD_SHIFT_VALUE_P(o, FIXNUM)
 #ifdef MRB_64BIT
-#define mrb_symbol_p(o) ((o).value.sym_flag == BOXWORD_SYMBOL_FLAG)
+#define mrb_symbol_p(o) (mrb_val_union(o).sym_flag == BOXWORD_SYMBOL_FLAG)
 #else
 #define mrb_symbol_p(o) BOXWORD_SHIFT_VALUE_P(o, SYMBOL)
 #endif
-#define mrb_undef_p(o) ((o).w == MRB_Qundef)
-#define mrb_nil_p(o)  ((o).w == MRB_Qnil)
-#define mrb_false_p(o) ((o).w == MRB_Qfalse)
-#define mrb_true_p(o)  ((o).w == MRB_Qtrue)
+#define mrb_undef_p(o) ((o) == MRB_Qundef)
+#define mrb_nil_p(o)  ((o) == MRB_Qnil)
+#define mrb_false_p(o) ((o) == MRB_Qfalse)
+#define mrb_true_p(o)  ((o) == MRB_Qtrue)
 #ifndef MRB_WITHOUT_FLOAT
 #define mrb_float_p(o) BOXWORD_OBJ_TYPE_P(o, FLOAT)
 #endif
@@ -143,18 +150,23 @@ MRB_API mrb_value mrb_word_boxing_float_value(struct mrb_state*, mrb_float);
 #define SET_FLOAT_VALUE(mrb,r,v) ((r) = mrb_word_boxing_float_value(mrb, v))
 #endif
 #define SET_CPTR_VALUE(mrb,r,v) ((r) = mrb_word_boxing_cptr_value(mrb, v))
-#define SET_UNDEF_VALUE(r) ((r).w = MRB_Qundef)
-#define SET_NIL_VALUE(r) ((r).w = MRB_Qnil)
-#define SET_FALSE_VALUE(r) ((r).w = MRB_Qfalse)
-#define SET_TRUE_VALUE(r) ((r).w = MRB_Qtrue)
+#define SET_UNDEF_VALUE(r) ((r) = MRB_Qundef)
+#define SET_NIL_VALUE(r) ((r) = MRB_Qnil)
+#define SET_FALSE_VALUE(r) ((r) = MRB_Qfalse)
+#define SET_TRUE_VALUE(r) ((r) = MRB_Qtrue)
 #define SET_BOOL_VALUE(r,b) ((b) ? SET_TRUE_VALUE(r) : SET_FALSE_VALUE(r))
 #define SET_INT_VALUE(r,n) BOXWORD_SET_SHIFT_VALUE(r, FIXNUM, n)
 #ifdef MRB_64BIT
-#define SET_SYM_VALUE(r,v) ((r).value.sym = v, (r).value.sym_flag = BOXWORD_SYMBOL_FLAG)
+#define SET_SYM_VALUE(r,v) do {\
+  union mrb_value mrb_value_union_variable;\
+  mrb_value_union_variable.sym = v;\
+  mrb_value_union_variable.sym_flag = BOXWORD_SYMBOL_FLAG;\
+  (r) = mrb_value_union_variable.w;\
+} while (0)
 #else
 #define SET_SYM_VALUE(r,n) BOXWORD_SET_SHIFT_VALUE(r, SYMBOL, n)
 #endif
-#define SET_OBJ_VALUE(r,v) ((r).value.p = v)
+#define SET_OBJ_VALUE(r,v) ((r) = (uintptr_t)v)
 
 MRB_INLINE enum mrb_vtype
 mrb_type(mrb_value o)
@@ -164,7 +176,7 @@ mrb_type(mrb_value o)
          mrb_fixnum_p(o) ? MRB_TT_FIXNUM :
          mrb_symbol_p(o) ? MRB_TT_SYMBOL :
          mrb_undef_p(o)  ? MRB_TT_UNDEF :
-         o.value.bp->tt;
+         mrb_val_union(o).bp->tt;
 }
 
 #endif  /* MRUBY_BOXING_WORD_H */

src/etc.c

@@ -151,12 +151,12 @@ mrb_obj_id(mrb_value obj)
 MRB_API mrb_value
 mrb_word_boxing_float_value(mrb_state *mrb, mrb_float f)
 {
-  mrb_value v;
+  union mrb_value v;
 
-  v.value.p = mrb_obj_alloc(mrb, MRB_TT_FLOAT, mrb->float_class);
-  v.value.fp->f = f;
-  MRB_SET_FROZEN_FLAG(v.value.bp);
-  return v;
+  v.p = mrb_obj_alloc(mrb, MRB_TT_FLOAT, mrb->float_class);
+  v.fp->f = f;
+  MRB_SET_FROZEN_FLAG(v.bp);
+  return v.w;
 }
 #endif  /* MRB_WITHOUT_FLOAT */
 #endif  /* MRB_WORD_BOXING */