This patch remove the old VAMS $log function. It could create confusion
with the Verilog $log task. Recent versions of VAMS and 1364-2005 use
$log10 for the base 10 logarithm.
This patch adds the constant system functions for Verilog-2005
and Verilog-AMS. These are evaluated at compile time. $abs(),
$min() and $max() support their polymorphic behavior in the
compiler where it really matters. They are always evaluated
as reals in the run time and the result/argument(s) will be
converted as needed.
The Verilog-2005 functions are available if using the 2005
generation (default) and if either the icarus-misc (also on
by default) or verilog-ams flags are set.
The Verilog-AMS functions are available if either the
icarus-misc or verilog-ams flags are set.
Verilog-2005 defines the base-10 log function to be $log10. This makes
sense because in C the log() function is the natural log. So add the
$log10 function.
Since there may be legacy code that uses the $log function, leave it
defined, but we should consider at least printing a warning when the
$log function is used.
The va_math.vpi module implements systen-function versions of the
Verilog-A math functions. This library was contributed by Cary R.
Also add the constants.vams include file. This is pretty much
direct from the Verilog-AMS LRM.
Cary R
Stephen Williams