URL
https://opencores.org/ocsvn/ao486/ao486/trunk
Subversion Repositories ao486
[/] [ao486/] [trunk/] [rtl/] [ao486/] [commands/] [CMD_JCXZ.txt] - Rev 2
Compare with Previous | Blame | View Log
<defines>
`define CMD_JCXZ #AUTOGEN_NEXT_CMD
</defines>
<decode>
dec_ready_one_one && decoder[7:0] == 8'hE3
`CMD_JCXZ
SET(dec_is_8bit);
SET(consume_one_one);
</decode>
<execute_local>
wire exe_jecxz_condition;
assign exe_jecxz_condition = (exe_address_16bit)? ecx[15:0] == 16'd0 : ecx == 32'd0;
</execute_local>
<execute>
IF(exe_cmd == `CMD_JCXZ);
IF(exe_mutex_current[`MUTEX_ECX_BIT]); SET(exe_waiting);
ELSE();
IF(exe_jecxz_condition && exe_branch_eip > cs_limit);
SET(exe_waiting);
SET(exe_trigger_gp_fault); //exception GP(0)
ENDIF();
SET(exe_branch, exe_jecxz_condition);
SET(exe_result_signals, { 4'd0, exe_jecxz_condition });
ENDIF();
ENDIF();
</execute>
<write>
IF(wr_cmd == `CMD_JCXZ);
IF(result_signals[0]);
// clear pipeline
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();
ENDIF();
</write>