VPI interface function vpi_put_value() NEEDS a delay capability

[r2com]

So in a file:
./src/grt/grt-vpi.adb

function:
function vpi_put_value (aObj : vpiHandle;
aValue : p_vpi_value;
aWhen : p_vpi_time;
aFlags : integer)
return vpiHandle

does not implement the delay capability of p_vpi_time type, thru aWhen parameter.
in fact its uncommented:
-- Ignoring aWhen and aFlags, for now.

This is a main roadblock for me to use GHDL, the thing is; for verification I am using solely the software based custom in-house written code which heavily using VPI.

And another requirement is - no HDL testbench, just c/c++ code.

If I want in one callback function initiated by vpi_register_cb modify MANY signals, each with own delays, the only way when using ghdl+cosim is: call multiple vpi_register_cb() [each with own delay] each with its own vpi_put_value() [without delays], however; that is very inefficient in terms of execution time since vpi_register_cb() is an expensive operation.

so.. are there plans to make fully functional VPI in ghdl or not?

OR, are there any plans to give fully functional VHPIDIRECT then?

or cosim is kinda always gonna stay on low priority and not extend to full capability?

right now, for me the only way is - if my HDL is in Verilog, and then I use icarus (which does implement delay in vpi_put_value())
but if my source is VHDL - ghdl is a no go.

[tgingold]

Although full VPI support might be too far fetched, yes I plan to implement useful features. Delay in vpi_put_value is part of it.

[r2com]

well, by full.. lets say supporting old obsolete ACC/TF or anything "_systf" stuff is not needed.

but fully functioning vpi_get_value/vpi_put_value/vpi_register_cb (with ALL flags support) as well as vecval data types passing is a must. and ability to force any signal deep in design.

in a current state its practically not even usable.
(cocotb is mega slow and which is reason why its not even used in any serious production-grade environment when it comes to VHDL code)

[Donmar001]

@r2com @tgingold @r2com Shall we communicate in the email，i want to ask some question about the vpi port meaasage.My email address is donmarjr148@gmail.com