OpenCores
URL https://opencores.org/ocsvn/ao486/ao486/trunk

Subversion Repositories ao486

[/] [ao486/] [trunk/] [rtl/] [ao486/] [commands/] [CMD_POPA.txt] - Rev 2

Compare with Previous | Blame | View Log


<defines>
`define CMD_POPA        #AUTOGEN_NEXT_CMD

`define CMDEX_POPA_STEP_0   4'd0
`define CMDEX_POPA_STEP_1   4'd1
`define CMDEX_POPA_STEP_2   4'd2
`define CMDEX_POPA_STEP_3   4'd3
`define CMDEX_POPA_STEP_4   4'd4
`define CMDEX_POPA_STEP_5   4'd5
`define CMDEX_POPA_STEP_6   4'd6
`define CMDEX_POPA_STEP_7   4'd7
</defines>

<decode>
dec_ready_one && decoder[7:0] == 8'h61
`CMD_POPA
SET(dec_cmdex, `CMDEX_POPA_STEP_0);
SET(consume_one);
SET(dec_is_complex);
</decode>

<microcode>
IF(mc_cmd == `CMD_POPA && mc_step < 6'd7);
    DIRECT(mc_cmd, mc_step[3:0]);
ENDIF();

IF(mc_cmd == `CMD_POPA && mc_step == 6'd7);
    LAST(`CMDEX_POPA_STEP_7);
ENDIF();
</microcode>

<read>
IF(rd_cmd == `CMD_POPA);
            
    SET(address_stack_pop);
    
    IF(rd_cmdex[2:0] > 3'd0); SET(address_stack_pop_speedup); ENDIF();
    
    IF(rd_cmdex[2:0] == 3'd7);  SET(rd_req_all); ENDIF();
    
    IF(rd_mutex_busy_memory || rd_mutex_busy_esp); SET(rd_waiting);
    ELSE();
        SET(rd_src_is_memory);

        SET(read_virtual);

        IF(~(read_for_rd_ready)); SET(rd_waiting); ENDIF();
    ENDIF();
ENDIF();
</read>

<execute>
IF(exe_cmd == `CMD_POPA);
    
    SET(offset_pop);

    IF(exe_ready);
        SAVE(exe_buffer, src);
        SET(exe_buffer_shift);
    ENDIF();
ENDIF();
</execute>

<write>
IF(wr_cmd == `CMD_POPA);
    //NOTE: exe_buffer can only be used if wr stage does not block (and it does not)

    IF(wr_cmdex[2:0] == 3'd0); SET(wr_make_esp_speculative); ENDIF();
    
    SAVE(esp, wr_stack_esp);
    
    IF(wr_cmdex[2:0] == 3'd7);
        SET(wr_make_esp_commit);
        
        SAVE(eax, { wr_operand_16bit? eax[31:16] : exe_buffer[31:16],           exe_buffer[15:0] });
        SAVE(ecx, { wr_operand_16bit? ecx[31:16] : exe_buffer_shifted[31:16],   exe_buffer_shifted[15:0] });
        SAVE(edx, { wr_operand_16bit? edx[31:16] : exe_buffer_shifted[63:48],   exe_buffer_shifted[47:32] });
        SAVE(ebx, { wr_operand_16bit? ebx[31:16] : exe_buffer_shifted[95:80],   exe_buffer_shifted[79:64] });
        //esp
        SAVE(ebp, { wr_operand_16bit? ebp[31:16] : exe_buffer_shifted[159:144], exe_buffer_shifted[143:128] });
        SAVE(esi, { wr_operand_16bit? esi[31:16] : exe_buffer_shifted[191:176], exe_buffer_shifted[175:160] });
        SAVE(edi, { wr_operand_16bit? edi[31:16] : exe_buffer_shifted[223:208], exe_buffer_shifted[207:192] });
    ELSE();
        SET(wr_not_finished);
    ENDIF();
ENDIF();
</write>

Compare with Previous | Blame | View Log

powered by: WebSVN 2.1.0

© copyright 1999-2024 OpenCores.org, equivalent to Oliscience, all rights reserved. OpenCores®, registered trademark.