OP_POP           1349 ext/mbstring/oniguruma/regcomp.c       r = add_opcode(reg, OP_POP);
OP_POP           5734 ext/mbstring/oniguruma/regcomp.c   { OP_POP,                 "pop",                  ARG_NON },
OP_POP           2468 ext/mbstring/oniguruma/regexec.c     case OP_POP:  MOP_IN(OP_POP);