yosys/docs/source/code_examples/fifo/fifo.out

-- Executing script file `fifo.ys' --
$ yosys fifo.v

-- Parsing `fifo.v' using frontend ` -vlog2k' --

1. Executing Verilog-2005 frontend: fifo.v
Parsing Verilog input from `fifo.v' to AST representation.
Storing AST representation for module `$abstract\addr_gen'.
Storing AST representation for module `$abstract\fifo'.
Successfully finished Verilog frontend.
echo on

yosys> hierarchy -top addr_gen

2. Executing HIERARCHY pass (managing design hierarchy).

3. Executing AST frontend in derive mode using pre-parsed AST for module `\addr_gen'.
Generating RTLIL representation for module `\addr_gen'.

3.1. Analyzing design hierarchy..
Top module:  \addr_gen

3.2. Analyzing design hierarchy..
Top module:  \addr_gen
Removing unused module `$abstract\fifo'.
Removing unused module `$abstract\addr_gen'.
Removed 2 unused modules.

yosys> select -set new_cells t:*

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix addr_gen_hier

4. Generating Graphviz representation of design.
Writing dot description to `addr_gen_hier.dot'.
Dumping module addr_gen to page 1.

yosys> proc

5. Executing PROC pass (convert processes to netlists).

yosys> proc_clean

5.1. Executing PROC_CLEAN pass (remove empty switches from decision trees).
Cleaned up 0 empty switches.

yosys> proc_rmdead

5.2. Executing PROC_RMDEAD pass (remove dead branches from decision trees).
Marked 2 switch rules as full_case in process $proc$fifo.v:13$1 in module addr_gen.
Removed a total of 0 dead cases.

yosys> proc_prune

5.3. Executing PROC_PRUNE pass (remove redundant assignments in processes).
Removed 0 redundant assignments.
Promoted 1 assignment to connection.

yosys> proc_init

5.4. Executing PROC_INIT pass (extract init attributes).
Found init rule in `\addr_gen.$proc$fifo.v:0$4'.
  Set init value: \addr = 8'00000000

yosys> proc_arst

5.5. Executing PROC_ARST pass (detect async resets in processes).
Found async reset \rst in `\addr_gen.$proc$fifo.v:13$1'.

yosys> proc_rom

5.6. Executing PROC_ROM pass (convert switches to ROMs).
Converted 0 switches.
<suppressed ~2 debug messages>

yosys> proc_mux

5.7. Executing PROC_MUX pass (convert decision trees to multiplexers).
Creating decoders for process `\addr_gen.$proc$fifo.v:0$4'.
Creating decoders for process `\addr_gen.$proc$fifo.v:13$1'.
     1/1: $0\addr[7:0]

yosys> proc_dlatch

5.8. Executing PROC_DLATCH pass (convert process syncs to latches).

yosys> proc_dff

5.9. Executing PROC_DFF pass (convert process syncs to FFs).
Creating register for signal `\addr_gen.\addr' using process `\addr_gen.$proc$fifo.v:13$1'.
  created $adff cell `$procdff$10' with positive edge clock and positive level reset.

yosys> proc_memwr

5.10. Executing PROC_MEMWR pass (convert process memory writes to cells).

yosys> proc_clean

5.11. Executing PROC_CLEAN pass (remove empty switches from decision trees).
Removing empty process `addr_gen.$proc$fifo.v:0$4'.
Found and cleaned up 2 empty switches in `\addr_gen.$proc$fifo.v:13$1'.
Removing empty process `addr_gen.$proc$fifo.v:13$1'.
Cleaned up 2 empty switches.

yosys> opt_expr -keepdc

5.12. Executing OPT_EXPR pass (perform const folding).
Optimizing module addr_gen.

yosys> select -set new_cells t:$mux t:*dff

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix addr_gen_proc

6. Generating Graphviz representation of design.
Writing dot description to `addr_gen_proc.dot'.
Dumping module addr_gen to page 1.

yosys> clean
Removed 0 unused cells and 4 unused wires.

yosys> show -notitle -format dot -prefix addr_gen_clean

7. Generating Graphviz representation of design.
Writing dot description to `addr_gen_clean.dot'.
Dumping module addr_gen to page 1.

yosys> design -reset

yosys> read_verilog fifo.v

8. Executing Verilog-2005 frontend: fifo.v
Parsing Verilog input from `fifo.v' to AST representation.
Generating RTLIL representation for module `\addr_gen'.
Generating RTLIL representation for module `\fifo'.
Successfully finished Verilog frontend.

yosys> hierarchy -check -top fifo

9. Executing HIERARCHY pass (managing design hierarchy).

9.1. Analyzing design hierarchy..
Top module:  \fifo
Used module:     \addr_gen
Parameter \MAX_DATA = 256

9.2. Executing AST frontend in derive mode using pre-parsed AST for module `\addr_gen'.
Parameter \MAX_DATA = 256
Generating RTLIL representation for module `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000'.
Parameter \MAX_DATA = 256
Found cached RTLIL representation for module `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000'.

9.3. Analyzing design hierarchy..
Top module:  \fifo
Used module:     $paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000

9.4. Analyzing design hierarchy..
Top module:  \fifo
Used module:     $paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000
Removing unused module `\addr_gen'.
Removed 1 unused modules.

yosys> proc

10. Executing PROC pass (convert processes to netlists).

yosys> proc_clean

10.1. Executing PROC_CLEAN pass (remove empty switches from decision trees).
Cleaned up 0 empty switches.

yosys> proc_rmdead

10.2. Executing PROC_RMDEAD pass (remove dead branches from decision trees).
Marked 2 switch rules as full_case in process $proc$fifo.v:64$24 in module fifo.
Marked 1 switch rules as full_case in process $proc$fifo.v:38$16 in module fifo.
Marked 2 switch rules as full_case in process $proc$fifo.v:13$32 in module $paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.
Removed a total of 0 dead cases.

yosys> proc_prune

10.3. Executing PROC_PRUNE pass (remove redundant assignments in processes).
Removed 0 redundant assignments.
Promoted 6 assignments to connections.

yosys> proc_init

10.4. Executing PROC_INIT pass (extract init attributes).
Found init rule in `\fifo.$proc$fifo.v:0$31'.
  Set init value: \count = 9'000000000
Found init rule in `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:0$35'.
  Set init value: \addr = 8'00000000

yosys> proc_arst

10.5. Executing PROC_ARST pass (detect async resets in processes).
Found async reset \rst in `\fifo.$proc$fifo.v:64$24'.
Found async reset \rst in `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:13$32'.

yosys> proc_rom

10.6. Executing PROC_ROM pass (convert switches to ROMs).
Converted 0 switches.
<suppressed ~5 debug messages>

yosys> proc_mux

10.7. Executing PROC_MUX pass (convert decision trees to multiplexers).
Creating decoders for process `\fifo.$proc$fifo.v:0$31'.
Creating decoders for process `\fifo.$proc$fifo.v:64$24'.
     1/1: $0\count[8:0]
Creating decoders for process `\fifo.$proc$fifo.v:38$16'.
     1/3: $1$memwr$\data$fifo.v:40$15_EN[7:0]$22
     2/3: $1$memwr$\data$fifo.v:40$15_DATA[7:0]$21
     3/3: $1$memwr$\data$fifo.v:40$15_ADDR[7:0]$20
Creating decoders for process `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:0$35'.
Creating decoders for process `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:13$32'.
     1/1: $0\addr[7:0]

yosys> proc_dlatch

10.8. Executing PROC_DLATCH pass (convert process syncs to latches).

yosys> proc_dff

10.9. Executing PROC_DFF pass (convert process syncs to FFs).
Creating register for signal `\fifo.\count' using process `\fifo.$proc$fifo.v:64$24'.
  created $adff cell `$procdff$55' with positive edge clock and positive level reset.
Creating register for signal `\fifo.\rdata' using process `\fifo.$proc$fifo.v:38$16'.
  created $dff cell `$procdff$56' with positive edge clock.
Creating register for signal `\fifo.$memwr$\data$fifo.v:40$15_ADDR' using process `\fifo.$proc$fifo.v:38$16'.
  created $dff cell `$procdff$57' with positive edge clock.
Creating register for signal `\fifo.$memwr$\data$fifo.v:40$15_DATA' using process `\fifo.$proc$fifo.v:38$16'.
  created $dff cell `$procdff$58' with positive edge clock.
Creating register for signal `\fifo.$memwr$\data$fifo.v:40$15_EN' using process `\fifo.$proc$fifo.v:38$16'.
  created $dff cell `$procdff$59' with positive edge clock.
Creating register for signal `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.\addr' using process `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:13$32'.
  created $adff cell `$procdff$60' with positive edge clock and positive level reset.

yosys> proc_memwr

10.10. Executing PROC_MEMWR pass (convert process memory writes to cells).

yosys> proc_clean

10.11. Executing PROC_CLEAN pass (remove empty switches from decision trees).
Removing empty process `fifo.$proc$fifo.v:0$31'.
Found and cleaned up 2 empty switches in `\fifo.$proc$fifo.v:64$24'.
Removing empty process `fifo.$proc$fifo.v:64$24'.
Found and cleaned up 1 empty switch in `\fifo.$proc$fifo.v:38$16'.
Removing empty process `fifo.$proc$fifo.v:38$16'.
Removing empty process `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:0$35'.
Found and cleaned up 2 empty switches in `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:13$32'.
Removing empty process `$paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.$proc$fifo.v:13$32'.
Cleaned up 5 empty switches.

yosys> opt_expr -keepdc

10.12. Executing OPT_EXPR pass (perform const folding).
Optimizing module fifo.
Optimizing module $paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.

yosys> select -set new_cells t:$memrd

yosys> show -color maroon3 c:fifo_reader -color cornflowerblue @new_cells -notitle -format dot -prefix rdata_proc o:rdata %ci*

11. Generating Graphviz representation of design.
Writing dot description to `rdata_proc.dot'.
Dumping selected parts of module fifo to page 1.

yosys> flatten

12. Executing FLATTEN pass (flatten design).
Deleting now unused module $paramod\addr_gen\MAX_DATA=s32'00000000000000000000000100000000.
<suppressed ~2 debug messages>

yosys> clean
Removed 3 unused cells and 25 unused wires.

yosys> select -set rdata_path o:rdata %ci*

yosys> select -set new_cells @rdata_path o:rdata %ci3 %d i:* %d

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_flat @rdata_path

13. Generating Graphviz representation of design.
Writing dot description to `rdata_flat.dot'.
Dumping selected parts of module fifo to page 1.

yosys> opt_dff

14. Executing OPT_DFF pass (perform DFF optimizations).
Adding EN signal on $procdff$55 ($adff) from module fifo (D = $0\count[8:0], Q = \count).
Adding EN signal on $flatten\fifo_writer.$procdff$60 ($adff) from module fifo (D = $flatten\fifo_writer.$procmux$51_Y, Q = \fifo_writer.addr).
Adding EN signal on $flatten\fifo_reader.$procdff$60 ($adff) from module fifo (D = $flatten\fifo_reader.$procmux$51_Y, Q = \fifo_reader.addr).

yosys> select -set new_cells t:$adffe

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_adffe o:rdata %ci*

15. Generating Graphviz representation of design.
Writing dot description to `rdata_adffe.dot'.
Dumping selected parts of module fifo to page 1.

yosys> wreduce

16. Executing WREDUCE pass (reducing word size of cells).
Removed top 31 bits (of 32) from port B of cell fifo.$add$fifo.v:68$27 ($add).
Removed top 23 bits (of 32) from port Y of cell fifo.$add$fifo.v:68$27 ($add).
Removed top 31 bits (of 32) from port B of cell fifo.$sub$fifo.v:70$30 ($sub).
Removed top 23 bits (of 32) from port Y of cell fifo.$sub$fifo.v:70$30 ($sub).
Removed top 1 bits (of 2) from port B of cell fifo.$auto$opt_dff.cc:195:make_patterns_logic$64 ($ne).
Removed cell fifo.$flatten\fifo_writer.$procmux$53 ($mux).
Removed top 31 bits (of 32) from port B of cell fifo.$flatten\fifo_writer.$add$fifo.v:20$34 ($add).
Removed top 24 bits (of 32) from port Y of cell fifo.$flatten\fifo_writer.$add$fifo.v:20$34 ($add).
Removed cell fifo.$flatten\fifo_reader.$procmux$53 ($mux).
Removed top 31 bits (of 32) from port B of cell fifo.$flatten\fifo_reader.$add$fifo.v:20$34 ($add).
Removed top 24 bits (of 32) from port Y of cell fifo.$flatten\fifo_reader.$add$fifo.v:20$34 ($add).
Removed top 23 bits (of 32) from wire fifo.$add$fifo.v:68$27_Y.
Removed top 24 bits (of 32) from wire fifo.$flatten\fifo_reader.$add$fifo.v:20$34_Y.
Removed top 24 bits (of 32) from wire fifo.$flatten\fifo_writer.$add$fifo.v:20$34_Y.

yosys> select -set new_cells t:$add %co t:$add %d

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_wreduce o:rdata %ci*

17. Generating Graphviz representation of design.
Writing dot description to `rdata_wreduce.dot'.
Dumping selected parts of module fifo to page 1.

yosys> opt_clean

18. Executing OPT_CLEAN pass (remove unused cells and wires).
Finding unused cells or wires in module \fifo..
Removed 0 unused cells and 5 unused wires.
<suppressed ~1 debug messages>

yosys> memory_dff

19. Executing MEMORY_DFF pass (merging $dff cells to $memrd).
Checking read port `\data'[0] in module `\fifo': merging output FF to cell.
    Write port 0: non-transparent.

yosys> select -set new_cells t:$memrd_v2

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_memrdv2 o:rdata %ci*

20. Generating Graphviz representation of design.
Writing dot description to `rdata_memrdv2.dot'.
Dumping selected parts of module fifo to page 1.

yosys> alumacc

21. Executing ALUMACC pass (create $alu and $macc cells).
Extracting $alu and $macc cells in module fifo:
  creating $macc model for $add$fifo.v:68$27 ($add).
  creating $macc model for $flatten\fifo_reader.$add$fifo.v:20$34 ($add).
  creating $macc model for $flatten\fifo_writer.$add$fifo.v:20$34 ($add).
  creating $macc model for $sub$fifo.v:70$30 ($sub).
  creating $alu model for $macc $sub$fifo.v:70$30.
  creating $alu model for $macc $flatten\fifo_writer.$add$fifo.v:20$34.
  creating $alu model for $macc $flatten\fifo_reader.$add$fifo.v:20$34.
  creating $alu model for $macc $add$fifo.v:68$27.
  creating $alu cell for $add$fifo.v:68$27: $auto$alumacc.cc:485:replace_alu$79
  creating $alu cell for $flatten\fifo_reader.$add$fifo.v:20$34: $auto$alumacc.cc:485:replace_alu$82
  creating $alu cell for $flatten\fifo_writer.$add$fifo.v:20$34: $auto$alumacc.cc:485:replace_alu$85
  creating $alu cell for $sub$fifo.v:70$30: $auto$alumacc.cc:485:replace_alu$88
  created 4 $alu and 0 $macc cells.

yosys> select -set new_cells t:$alu t:$macc

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_alumacc o:rdata %ci*

22. Generating Graphviz representation of design.
Writing dot description to `rdata_alumacc.dot'.
Dumping selected parts of module fifo to page 1.

yosys> memory_collect

23. Executing MEMORY_COLLECT pass (generating $mem cells).

yosys> select -set new_cells t:$mem_v2

yosys> select -set rdata_path @new_cells %ci*:-$mem_v2[WR_DATA,WR_ADDR,WR_EN] @new_cells %co* %%

yosys> show -color maroon3 @new_cells -notitle -format dot -prefix rdata_coarse @rdata_path

24. Generating Graphviz representation of design.
Writing dot description to `rdata_coarse.dot'.
Dumping selected parts of module fifo to page 1.