Flow of Opcode Execution using testnap

If we pass two opcode's together againt some input flist in testnap then what would be the flow of execution of the opcodes and Is it mandatory to have same flist or we can pass different flist for both the opcodes ?

For Example:-

Input Flist :-

r << XXX 1

0 PIN_FLD_POID           POID [0] 0.0.0.1 /account 1

0 PIN_FLD_START_T      TSTAMP [0] ($mytime)

0 PIN_FLD_END_T        TSTAMP [0] ($mytime)

0 PIN_FLD_ACCOUNT_NO      STR [0] "ROOT"

XXX

xop PCM_OP_RATE_TAX_CALC PCM_OPFLG_CALC_ONLY 1