process_rules.rst

Process Rules

process_001

This rule checks the indent of the process declaration.

Violation

architecture rtl of fifo is

begin

proc_a : process (rd_en, wr_en, data_in, data_out,

Fix

architecture rtl of fifo is

begin

  proc_a : process (rd_en, wr_en, data_in, data_out,

process_002

This rule checks for a single space after the process keyword.

Violation

proc_a : process(rd_en, wr_en, data_in, data_out,

proc_a : process    (rd_en, wr_en, data_in, data_out,

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,

proc_a : process (rd_en, wr_en, data_in, data_out,

process_003

This rule checks the indent of the begin keyword.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
  begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_004

This rule checks the begin keyword has proper case.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
BEGIN

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_005

This rule checks the process keyword has proper case.

Violation

proc_a : PROCESS (rd_en, wr_en, data_in, data_out,

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,

process_006

This rule checks the indent of the end process keywords.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

  end process proc_a;

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

end process proc_a;

process_007

This rule checks for a single space after the end keyword.

Violation

end   process proc_a;

Fix

end process proc_a;

process_008

This rule checks the end keyword has proper case.

Violation

END process proc_a;

Fix

end process proc_a;

process_009

This rule checks the process keyword has proper case in the end process line.

Violation

end PROCESS proc_a;

Fix

end process proc_a;

process_010

This rule checks the begin keyword is on its own line.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_011

This rule checks for a blank line below the end process keyword.

Violation

end process proc_a;
wr_en <= wr_en;

Fix

end process proc_a;

wr_en <= wr_en;

process_012

This rule checks for the existence of the is keyword.

Violation

proc_a : process
begin
end process;

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 )
begin
end process;

Fix

proc_a : process is
begin
end process;


proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin
end process;

process_013

This rule checks the is keyword has proper case.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) IS
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_014

This rule checks for a single space before the is keyword.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 )     is
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_015

This rule checks for blank lines or comments above the process declaration.

The default style is no_code.

Violation

-- This process performs FIFO operations.
proc_a : process (rd_en, wr_en, data_in, data_out,

wr_en <= wr_en;
proc_a : process (rd_en, wr_en, data_in, data_out,

Fix

-- This process performs FIFO operations.
proc_a : process (rd_en, wr_en, data_in, data_out,

wr_en <= wr_en;

proc_a : process (rd_en, wr_en, data_in, data_out,

process_016

This rule checks the process has a label.

Violation

process (rd_en, wr_en, data_in, data_out,
         rd_full, wr_full
        ) is
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_017

This rule checks the process label has proper case.

Violation

PROC_A : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_018

This rule checks the end process line has a label. The closing label will be added if the opening process label exists.

Violation

end process;

Fix

end process proc_a;

process_019

This rule checks the end process label has proper case.

Violation

end process PROC_A;

Fix

end process proc_a;

process_020

This rule checks the indentation of multiline sensitivity lists.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                     rd_full, wr_full,
            overflow, underflow
                 ) is begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full,
                  overflow, underflow
                 ) is
begin

process_021

This rule checks for blank lines above the begin keyword if there are no process declarative items.

Violation

proc_a : process

begin


proc_a : process (rd_en, wr_en)

begin


proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is



begin

Fix

proc_a : process
begin


proc_a : process (rd_en, wr_en)
begin


proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_022

This rule checks for a blank line below the begin keyword.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin
  rd_en <= '0';

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

  rd_en <= '0';

process_023

This rule checks for a blank line above the end process keyword.

Violation

wr_en <= '1';

end process proc_a;

Fix

wr_en <= '1';

end process proc_a;

process_024

This rule checks for a single space after the process label.

Violation

proc_a: process (rd_en, wr_en, data_in, data_out,
                 rd_full, wr_full
                ) is
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_025

This rule checks for a single space after the colon and before the process keyword.

Violation

proc_a :process (rd_en, wr_en, data_in, data_out,
                 rd_full, wr_full
                ) is begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
begin

process_026

This rule checks for blank lines above the first declarative line, if it exists.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is
  -- Keep track of the number of words in the FIFO
  variable word_count : integer;
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is

  -- Keep track of the number of words in the FIFO
  variable word_count : integer;
begin

process_027

This rule checks for blank lines above the begin keyword if a declarative item exists.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is

  -- Keep track of the number of words in the FIFO
  variable word_count : integer;
begin

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 ) is

  -- Keep track of the number of words in the FIFO
  variable word_count : integer;

begin

process_028

This rule checks the alignment of the closing parenthesis of a sensitivity list. Parenthesis on multiple lines should be in the same column.

Violation

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                    )

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 )

process_029

This rule checks for the format of clock definitions in clock processes. The rule can be set to enforce event definition:

if (clk'event and clk = '1') then

..or edge definition:

if (rising_edge(clk)) then

event configuration

Note

This is the default configuration.

Violation

if (rising_edge(clk)) then

if (falling_edge(clk)) then

Fix

if (clk'event and clk = '1') then

if (clk'event and clk = '0') then

edge configuration

Note

Configuration this by setting the 'clock' attribute to 'edge'

{
  "rule":{
    "process_029":{
       "clock":"edge"
    }
  }
}

Violation

if (clk'event and clk = '1') then

if (clk'event and clk = '0') then

Fix

if (rising_edge(clk)) then

if (falling_edge(clk)) then

process_030

This rule checks for a single signal per line in a sensitivity list that is not the last one. The sensitivity list is required by the compiler, but provides no useful information to the reader. Therefore, the vertical spacing of the sensitivity list should be minimized. This will help with code readability.

Note

This rule is left to the user to fix.

Violation

proc_a : process (rd_en,
                  wr_en,
                  data_in,
                  data_out,
                  rd_full,
                  wr_full
                 )

Fix

proc_a : process (rd_en, wr_en, data_in, data_out,
                  rd_full, wr_full
                 )

process_031

This rule checks for alignment of identifiers in the process declarative region.

Violation

proc_1 : process(all) is

 variable     var1 : boolean;
 constant  cons1 : integer;
 file            file1  : load_file_file open read_mode is load_file_name;

begin

end process proc_1;

Fix

proc_1 : process(all) is

 variable var1 : boolean;
 constant cons1 : integer;
 file     file1  : load_file_file open read_mode is load_file_name;

begin

end process proc_1;

process_032

This rule checks the process label is on the same line as the process keyword.

Violation

proc_1 :

process(all) is

Fix

proc_1 : process(all) is

process_033

This rule checks the colons are in the same column for all declarations in the process declarative part.

Violation

variable var1 : natural;
variable var2  : natural;
constant c_period : time;
file my_test_input : my_file_type;

Fix

variable var1      : natural;
variable var2      : natural;
constant c_period  : time;
file my_test_input : my_file_type;

process_034

This rule aligns inline comments between the end of the process sensitivity list and the process begin keyword.

Violation

proc_1 : process () is

   variable counter : integer range 0 to 31;     -- Counts the number of frames received
   variable width   : natural range 0 to 255; -- Keeps track of the data word size

   variable size    : natural range 0 to 7; -- Keeps track of the frame size

begin

Fix

proc_1 : process () is

   variable counter : integer range 0 to 31;  -- Counts the number of frames received
   variable width   : natural range 0 to 255; -- Keeps track of the data word size

   variable size    : natural range 0 to 7;   -- Keeps track of the frame size

begin

process_035

This rule checks the alignment of inline comments between the process begin and end process lines.

Violation

proc_1: process () is
begin

  a <= '1';   -- Assert
  b <= '0';       -- Deassert
  c <= '1'; -- Enable

end process proc_1;

Fix

proc_1: process () is
begin

  a <= '1'; -- Assert
  b <= '0'; -- Deassert
  c <= '1'; -- Enable

end process proc_1;

process_036

This rule checks for valid prefixes on process labels. The default prefix is proc_.

Violation

main: process () is

Fix

proc_main: process () is

process_400

This rule checks the alignment of the <= and := operators over consecutive sequential assignments in the process_statement_part.

Following extra configurations are supported:

• if_control_statements_ends_group,
• case_control_statements_ends_group.
• case_keyword_statements_ends_group.
• loop_control_statements_ends_group,

Violation

wr_en <= '1';
rd_en   <= '0';
v_variable := 10;

Fix

wr_en      <= '1';
rd_en      <= '0';
v_variable := 10;

process_401

This rule checks the colons are in the same column for all attribute specifications.

Violation

attribute mark_debug of wr_en : signal is "true";
attribute mark_debug of almost_empty : signal is "true";
attribute mark_debug of full : signal is "true";

Fix

attribute mark_debug of wr_en        : signal is "true";
attribute mark_debug of almost_empty : signal is "true";
attribute mark_debug of full         : signal is "true";

process_600

This rule checks for valid suffixes on process labels. The default suffix is _proc.

Violation

main: process () is

Fix

main_proc: process () is