// R_r(decor) applies decoration decor to register r, which is an internal
// register name. The internal register names are: `ip', `a', `b', `c', `d',
// `si', `di', `bp', `sp', `r8'--`r15'.
+#define R_nil(decor) nil
#define R_ip(decor) _DECOR(ip, decor, ip)
#define R_a(decor) _DECOR(abcd, decor, a)
#define R_b(decor) _DECOR(abcd, decor, b)
// assembler-level register name, in place of any decoration that register
// name has already.
+#define _REGFORM_nil(decor) R_nil(decor)
+
#define _REGFORM_ip(decor) R_ip(decor)
#define _REGFORM_eip(decor) R_ip(decor)
// Internal macros: `_REGFORM_r(decor)' applies decoration decor to register
// name r.
+#define _REGFORM_nil(decor) nil
+
#define _REGFORM_s0(decor) _DECOR(s, decor, 0)
#define _REGFORM_s1(decor) _DECOR(s, decor, 1)
#define _REGFORM_s2(decor) _DECOR(s, decor, 2)