diff --git a/bignum.c b/bignum.c
index 52f62b8331..7adf55d1f0 100644
--- a/bignum.c
+++ b/bignum.c
@@ -5387,18 +5387,14 @@ rb_integer_float_eq(VALUE x, VALUE y)
     if (FIXNUM_P(x)) {
 #if SIZEOF_LONG * CHAR_BIT < DBL_MANT_DIG /* assume FLT_RADIX == 2 */
         double xd = (double)FIX2LONG(x);
-        if (xd != yd)
-            return Qfalse;
-        return Qtrue;
+        return RBOOL(xd == yd);
 #else
         long xn, yn;
         if (yi < LONG_MIN || LONG_MAX_as_double <= yi)
             return Qfalse;
         xn = FIX2LONG(x);
         yn = (long)yi;
-        if (xn != yn)
-            return Qfalse;
-        return Qtrue;
+        return RBOOL(xn == yn);
 #endif
     }
     y = rb_dbl2big(yi);
@@ -5527,8 +5523,7 @@ rb_big_eq(VALUE x, VALUE y)
     }
     if (BIGNUM_SIGN(x) != BIGNUM_SIGN(y)) return Qfalse;
     if (BIGNUM_LEN(x) != BIGNUM_LEN(y)) return Qfalse;
-    if (MEMCMP(BDIGITS(x),BDIGITS(y),BDIGIT,BIGNUM_LEN(y)) != 0) return Qfalse;
-    return Qtrue;
+    return RBOOL(MEMCMP(BDIGITS(x),BDIGITS(y),BDIGIT,BIGNUM_LEN(y)) == 0);
 }
 
 VALUE
@@ -5537,8 +5532,7 @@ rb_big_eql(VALUE x, VALUE y)
     if (!RB_BIGNUM_TYPE_P(y)) return Qfalse;
     if (BIGNUM_SIGN(x) != BIGNUM_SIGN(y)) return Qfalse;
     if (BIGNUM_LEN(x) != BIGNUM_LEN(y)) return Qfalse;
-    if (MEMCMP(BDIGITS(x),BDIGITS(y),BDIGIT,BIGNUM_LEN(y)) != 0) return Qfalse;
-    return Qtrue;
+    return RBOOL(MEMCMP(BDIGITS(x),BDIGITS(y),BDIGIT,BIGNUM_LEN(y)) == 0);
 }
 
 VALUE
@@ -6821,10 +6815,7 @@ rb_big_bit_length(VALUE big)
 VALUE
 rb_big_odd_p(VALUE num)
 {
-    if (BIGNUM_LEN(num) != 0 && BDIGITS(num)[0] & 1) {
-	return Qtrue;
-    }
-    return Qfalse;
+    return RBOOL(BIGNUM_LEN(num) != 0 && BDIGITS(num)[0] & 1);
 }
 
 VALUE
diff --git a/compar.c b/compar.c
index 7974017e2b..e9d1ac41f9 100644
--- a/compar.c
+++ b/compar.c
@@ -84,8 +84,7 @@ cmp_equal(VALUE x, VALUE y)
     c = rb_exec_recursive_paired_outer(cmp_eq_recursive, x, y, y);
 
     if (NIL_P(c)) return Qfalse;
-    if (rb_cmpint(c, x, y) == 0) return Qtrue;
-    return Qfalse;
+    return RBOOL(rb_cmpint(c, x, y) == 0);
 }
 
 static int
diff --git a/complex.c b/complex.c
index ec77aeb588..ea3c137461 100644
--- a/complex.c
+++ b/complex.c
@@ -1451,10 +1451,7 @@ rb_complex_finite_p(VALUE self)
 {
     get_dat1(self);
 
-    if (f_finite_p(dat->real) && f_finite_p(dat->imag)) {
-	return Qtrue;
-    }
-    return Qfalse;
+    return RBOOL(f_finite_p(dat->real) && f_finite_p(dat->imag));
 }
 
 /*
diff --git a/error.c b/error.c
index b589384303..84902204d2 100644
--- a/error.c
+++ b/error.c
@@ -1548,9 +1548,7 @@ exc_equal(VALUE exc, VALUE obj)
 
     if (!rb_equal(rb_attr_get(exc, id_mesg), mesg))
 	return Qfalse;
-    if (!rb_equal(exc_backtrace(exc), backtrace))
-	return Qfalse;
-    return Qtrue;
+    return rb_equal(exc_backtrace(exc), backtrace);
 }
 
 /*
@@ -1638,10 +1636,7 @@ exit_success_p(VALUE exc)
     if (NIL_P(status_val))
 	return Qtrue;
     status = NUM2INT(status_val);
-    if (WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS)
-	return Qtrue;
-
-    return Qfalse;
+    return RBOOL(WIFEXITED(status) && WEXITSTATUS(status) == EXIT_SUCCESS);
 }
 
 static VALUE
diff --git a/file.c b/file.c
index f5d01fda2a..98b9d50446 100644
--- a/file.c
+++ b/file.c
@@ -2019,8 +2019,7 @@ rb_file_file_p(VALUE obj, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
-    if (S_ISREG(st.st_mode)) return Qtrue;
-    return Qfalse;
+    return RBOOL(S_ISREG(st.st_mode));
 }
 
 /*
@@ -2039,8 +2038,7 @@ rb_file_zero_p(VALUE obj, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
-    if (st.st_size == 0) return Qtrue;
-    return Qfalse;
+    return RBOOL(st.st_size == 0);
 }
 
 /*
@@ -2080,8 +2078,7 @@ rb_file_owned_p(VALUE obj, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
-    if (st.st_uid == geteuid()) return Qtrue;
-    return Qfalse;
+    return RBOOL(st.st_uid == geteuid());
 }
 
 static VALUE
@@ -2090,8 +2087,7 @@ rb_file_rowned_p(VALUE obj, VALUE fname)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
-    if (st.st_uid == getuid()) return Qtrue;
-    return Qfalse;
+    return RBOOL(st.st_uid == getuid());
 }
 
 /*
@@ -2124,8 +2120,7 @@ check3rdbyte(VALUE fname, int mode)
     struct stat st;
 
     if (rb_stat(fname, &st) < 0) return Qfalse;
-    if (st.st_mode & mode) return Qtrue;
-    return Qfalse;
+    return RBOOL(st.st_mode & mode);
 }
 #endif
 
diff --git a/numeric.c b/numeric.c
index 39c2bd7b82..3b481b3869 100644
--- a/numeric.c
+++ b/numeric.c
@@ -755,18 +755,10 @@ static VALUE
 int_zero_p(VALUE num)
 {
     if (FIXNUM_P(num)) {
-	if (FIXNUM_ZERO_P(num)) {
-	    return Qtrue;
-	}
+        return RBOOL(FIXNUM_ZERO_P(num));
     }
-    else {
-        assert(RB_BIGNUM_TYPE_P(num));
-	if (rb_bigzero_p(num)) {
-	    /* this should not happen usually */
-	    return Qtrue;
-	}
-    }
-    return Qfalse;
+    assert(RB_BIGNUM_TYPE_P(num));
+    return RBOOL(rb_bigzero_p(num));
 }
 
 VALUE
@@ -1368,7 +1360,7 @@ rb_float_equal(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
     if (isnan(a)) return Qfalse;
 #endif
-    return (a == b)?Qtrue:Qfalse;
+    return RBOOL(a == b);
 }
 
 #define flo_eq rb_float_equal
@@ -1491,7 +1483,7 @@ rb_float_gt(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
     if (isnan(a)) return Qfalse;
 #endif
-    return (a > b)?Qtrue:Qfalse;
+    return RBOOL(a > b);
 }
 
 /*
@@ -1528,7 +1520,7 @@ flo_ge(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
     if (isnan(a)) return Qfalse;
 #endif
-    return (a >= b)?Qtrue:Qfalse;
+    return RBOOL(a >= b);
 }
 
 /*
@@ -1565,7 +1557,7 @@ flo_lt(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
     if (isnan(a)) return Qfalse;
 #endif
-    return (a < b)?Qtrue:Qfalse;
+    return RBOOL(a < b);
 }
 
 /*
@@ -1602,7 +1594,7 @@ flo_le(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
     if (isnan(a)) return Qfalse;
 #endif
-    return (a <= b)?Qtrue:Qfalse;
+    return RBOOL(a <= b);
 }
 
 /*
@@ -1627,8 +1619,7 @@ rb_float_eql(VALUE x, VALUE y)
 #if MSC_VERSION_BEFORE(1300)
 	if (isnan(a) || isnan(b)) return Qfalse;
 #endif
-	if (a == b)
-	    return Qtrue;
+    return RBOOL(a == b);
     }
     return Qfalse;
 }
@@ -4094,8 +4085,7 @@ static VALUE
 fix_gt(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	if (FIX2LONG(x) > FIX2LONG(y)) return Qtrue;
-	return Qfalse;
+        return RBOOL(FIX2LONG(x) > FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
 	return RBOOL(rb_big_cmp(y, x) == INT2FIX(-1));
@@ -4133,8 +4123,7 @@ static VALUE
 fix_ge(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	if (FIX2LONG(x) >= FIX2LONG(y)) return Qtrue;
-	return Qfalse;
+        return RBOOL(FIX2LONG(x) >= FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
 	return RBOOL(rb_big_cmp(y, x) != INT2FIX(+1));
@@ -4172,8 +4161,7 @@ static VALUE
 fix_lt(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	if (FIX2LONG(x) < FIX2LONG(y)) return Qtrue;
-	return Qfalse;
+        return RBOOL(FIX2LONG(x) < FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
 	return RBOOL(rb_big_cmp(y, x) == INT2FIX(+1));
@@ -4211,8 +4199,7 @@ static VALUE
 fix_le(VALUE x, VALUE y)
 {
     if (FIXNUM_P(y)) {
-	if (FIX2LONG(x) <= FIX2LONG(y)) return Qtrue;
-	return Qfalse;
+        return RBOOL(FIX2LONG(x) <= FIX2LONG(y));
     }
     else if (RB_BIGNUM_TYPE_P(y)) {
 	return RBOOL(rb_big_cmp(y, x) != INT2FIX(-1));
diff --git a/re.c b/re.c
index 2afa824cad..5c5b53dddc 100644
--- a/re.c
+++ b/re.c
@@ -1724,8 +1724,7 @@ rb_reg_nth_defined(int nth, VALUE match)
 	nth += regs->num_regs;
 	if (nth <= 0) return Qnil;
     }
-    if (BEG(nth) == -1) return Qfalse;
-    return Qtrue;
+    return RBOOL(BEG(nth) != -1);
 }
 
 VALUE
@@ -3053,10 +3052,7 @@ rb_reg_equal(VALUE re1, VALUE re2)
     if (RREGEXP_PTR(re1)->options != RREGEXP_PTR(re2)->options) return Qfalse;
     if (RREGEXP_SRC_LEN(re1) != RREGEXP_SRC_LEN(re2)) return Qfalse;
     if (ENCODING_GET(re1) != ENCODING_GET(re2)) return Qfalse;
-    if (memcmp(RREGEXP_SRC_PTR(re1), RREGEXP_SRC_PTR(re2), RREGEXP_SRC_LEN(re1)) == 0) {
-	return Qtrue;
-    }
-    return Qfalse;
+    return RBOOL(memcmp(RREGEXP_SRC_PTR(re1), RREGEXP_SRC_PTR(re2), RREGEXP_SRC_LEN(re1)) == 0);
 }
 
 /*
diff --git a/string.c b/string.c
index a0cf94ca9f..267efd407c 100644
--- a/string.c
+++ b/string.c
@@ -4630,8 +4630,7 @@ rb_str_include_range_p(VALUE beg, VALUE end, VALUE val, VALUE exclusive)
 
 		if (ISASCII(b) && ISASCII(e) && ISASCII(v)) {
 		    if (b <= v && v < e) return Qtrue;
-		    if (!RTEST(exclusive) && v == e) return Qtrue;
-		    return Qfalse;
+            return RBOOL(!RTEST(exclusive) && v == e);
 		}
 	    }
 	}
diff --git a/thread.c b/thread.c
index 7e1c1a65bb..9008467206 100644
--- a/thread.c
+++ b/thread.c
@@ -3370,13 +3370,7 @@ rb_thread_stop_p(VALUE thread)
     if (rb_threadptr_dead(th)) {
 	return Qtrue;
     }
-    else if (th->status == THREAD_STOPPED ||
-	     th->status == THREAD_STOPPED_FOREVER) {
-	return Qtrue;
-    }
-    else {
-	return Qfalse;
-    }
+    return RBOOL(th->status == THREAD_STOPPED || th->status == THREAD_STOPPED_FOREVER);
 }
 
 /*
@@ -3770,12 +3764,7 @@ rb_thread_key_p(VALUE self, VALUE key)
     if (!id || local_storage == NULL) {
 	return Qfalse;
     }
-    else if (rb_id_table_lookup(local_storage, id, &val)) {
-	return Qtrue;
-    }
-    else {
-	return Qfalse;
-    }
+    return RBOOL(rb_id_table_lookup(local_storage, id, &val));
 }
 
 static enum rb_id_table_iterator_result
diff --git a/variable.c b/variable.c
index 0e442241ea..aa1fdd022e 100644
--- a/variable.c
+++ b/variable.c
@@ -783,8 +783,7 @@ MJIT_FUNC_EXPORTED VALUE
 rb_gvar_defined(ID id)
 {
     struct rb_global_entry *entry = rb_global_entry(id);
-    if (entry->var->getter == rb_gvar_undef_getter) return Qfalse;
-    return Qtrue;
+    return RBOOL(entry->var->getter != rb_gvar_undef_getter);
 }
 
 rb_gvar_getter_t *
@@ -1099,10 +1098,7 @@ generic_ivar_defined(VALUE obj, ID id)
     if (!iv_index_tbl_lookup(iv_index_tbl, id, &index)) return Qfalse;
     if (!gen_ivtbl_get(obj, id, &ivtbl)) return Qfalse;
 
-    if ((index < ivtbl->numiv) && (ivtbl->ivptr[index] != Qundef))
-	return Qtrue;
-
-    return Qfalse;
+    return RBOOL((index < ivtbl->numiv) && (ivtbl->ivptr[index] != Qundef));
 }
 
 static int