As a quirk of the (System)Verilog grammar a function or task argument list
with no arguments can not be distinguished from a argument list with a
single empty argument. The iverilog parses it as the latter. There are
currently many places in the code base where this is fixed up in slightly
different ways.
Fix this up in the parser in a central way before passing the arguments to
the elaboration stage.
The existing implementation in some cases removes all empty trailing
arguments. While this works to handle the case for zero arguments it also
hides some errors that should be detected. E.g. in the following 3
arguments are passed to a function which only takes two arguments. But no
error is reported since the explicitly specified empty arguments are
removed.
```
function f(integer a, integer b = 2); ... endfunction
f(1,,);
```
In the new implementation the empty argument will only be removed if there
is exactly one empty argument in the argument list.
Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Some new shadow issues have crept in. This patch fixes these new
issues and adds -Wshadow to the normal warning flags to keep any
new occurrences from happening.
Functions that appear in continuous assignment expressions and that
have hidden dependencies or side effects need to be re-evaluated
whenever any input to the expression changes. This patch adds support
in the compiler and vvp runtime to enable this. This is currently
activated for any system function call that has no arguments. The
user may also force it to be used for any user function by passing
the option -gstrict-ca-eval to the compiler driver.
This patch also removes the -dautomatic option which was used for
gaining confidence in the code that supports automatic tasks and
functions. It is believed that the testsuite provides reasonable
fault coverage, and further tests can be added if bugs are found.
Continue cleaning up shadowed variables, flagged by turning on -Wshadow.
No intended change in functionality. Patch looks right, and is tested
to compile and run on my machine. No regressions in test suite.
Contribution statements have an l-value and r-value. Parse those
expressions into pform so that elaboration has something to work with.
In this process, this patch also changes the PECallFunction class to
use the vector template instead of the svector template. The latter
doesn't add anything over the STL vector template, so this is a start
of working the svector out.
Allow user defined functions to take real value arguments and return
real value results in net contexts. Use the data type of the nets
attached to the ports to define the data types of the arguments and
return value.
In nets, if system functions return a real value the function lookup
was getting the correct width, but was also setting the width to 0,
which confused down-stream net handling. Real-value system fuctions
have a width of 1. (1 real-valued scalar.)
Rework the handling of file names to use a perm_string heap to hold
the file names, instead of the custom file name heap in the lexor.
Also rename the get_line to get_fileline to reflect its real duties.
This latter chage touched a lot of files.
Cary R
Lars-Peter Clausen
Martin Whitaker
Stephen Williams
Arun Persaud
Martin Whitaker
Larry Doolittle
steve