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[/] [ao486/] [trunk/] [rtl/] [ao486/] [commands/] [CMD_RET_near.txt] - Rev 8
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<defines>
`define CMD_RET_near #AUTOGEN_NEXT_CMD
// glob_param_2 --> eip
`define CMDEX_RET_near 4'd0
`define CMDEX_RET_near_imm 4'd1
`define CMDEX_RET_near_LAST 4'd2
</defines>
<decode>
(dec_ready_one && decoder[7:0] == 8'hC3) || (dec_ready_one_two && decoder[7:0] == 8'hC2)
`CMD_RET_near
IF(decoder[0] == 1'b0); SET(dec_cmdex, `CMDEX_RET_near_imm); ELSE(); SET(dec_cmdex, `CMDEX_RET_near); ENDIF();
IF(decoder[0] == 1'b0); SET(consume_one_two); ELSE(); SET(consume_one); ENDIF();
SET(dec_is_complex);
</decode>
<microcode>
IF(`CMDEX_RET_near_imm);
LAST(`CMDEX_RET_near_LAST);
ENDIF();
IF(`CMDEX_RET_near);
LAST(`CMDEX_RET_near_LAST);
ENDIF();
</microcode>
<read>
IF(rd_cmd == `CMD_RET_near && rd_cmdex != `CMDEX_RET_near_LAST);
SET(address_stack_pop);
// waiting for esp in 'address_ready'
SET(rd_glob_param_2_set);
SET(rd_glob_param_2_value, (rd_operand_16bit)? { 16'd0, read_4[15:0] } : read_4);
SET(rd_req_esp);
IF(rd_mutex_busy_memory); SET(rd_waiting);
ELSE();
SET(read_virtual);
IF(~(read_for_rd_ready)); SET(rd_waiting); ENDIF();
ENDIF();
ENDIF();
</read>
<execute>
IF(exe_cmd == `CMD_RET_near && exe_cmdex != `CMDEX_RET_near_LAST);
IF(exe_cmdex == `CMDEX_RET_near);
SET(offset_pop);
ENDIF();
IF(exe_cmdex == `CMDEX_RET_near_imm);
SET(offset_ret);
ENDIF();
SET(exe_eip_from_glob_param_2);
IF(glob_param_2 > cs_limit);
SET(exe_waiting);
SET(exe_trigger_gp_fault); //exception GP(0)
ENDIF();
ENDIF();
</execute>
<write>
IF(wr_cmd == `CMD_RET_near && wr_cmdex != `CMDEX_RET_near_LAST);
SAVE(esp, wr_stack_esp);
SET(wr_req_reset_pr);
SET(wr_req_reset_dec);
SET(wr_req_reset_micro);
SET(wr_req_reset_rd);
SET(wr_req_reset_exe);
ENDIF();
</write>
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