get pins, nets, ports - max fanout

proc make_hfn_timing_ideal {HFN_FANOUT_THRESHOLD} {
set all_nets [get_net -hier -top_net_of_hierarchical_group]
set total_high_fanout_nets 0
echo -n “Searching [sizeof_collection $all_nets] nets “

echo “looking for fanouts > $HFN_FANOUT_THRESHOLD”
foreach_in_collection the_net $all_nets {
set fanout [sizeof_collection \
[filter [get_pins -quiet -leaf -of_objects $the_net] “pin_direction!=out”]]
if {$fanout > $HFN_FANOUT_THRESHOLD} {
if {[regexp {\*Logic[01]\*} [get_attribute $the_net base_name]]} {
# this is a tie-off net, so no need to change it
continue
}

# find all the pins on the net
set all_pins [get_pins -leaf -of_objects $the_net]

# find all the pins driving the net
set driver_pins [filter [get_pins -quiet -leaf -of_objects $the_net] “pin_direction==out”]

# find all the ports driving the net
set driver_ports [filter \
[get_ports -quiet -of_objects $the_net] \
“port_direction==in”]

# report the drivers
foreach_in_collection the_pin $driver_pins {
echo -n “Setting Ideal Net on [get_object_name $the_net] with fanout $fanout”
echo “ driven by pin [get_attribute $the_pin full_name]”
set_ideal_network -no_propagate $driver_pins
}

foreach_in_collection the_port $driver_ports {
echo -n “Setting Ideal Net on [get_object_name $the_net] with fanout $fanout”
echo “ driven by port [get_attribute $the_port full_name]”
set_ideal_network -no_propagate $the_port
}

incr total_high_fanout_nets
}
}
  echo “Fixed $total_high_fanout_nets nets with fanouts > $HFN_FANOUT_THRESHOLD”
}

and now you can invoke this in your analysis scripts
# fix high-fanout nets
if {$FIX_HFN} {
make_hfn_timing_ideal $HFN_FANOUT_THRESHOLD
}
The HFN_FANOUT_THRESHOLD parameter defines the cutoff. This should agree with the
value used in the synthesis scripts to control which nets are idealized during synthesis.

sorting an array..

@ascending = sort {$a cmp $b} @a;

@descending = sort {$b cmp $a} @a;
(OR)
@descending = reverse @ascending;

appending & reversing arrrays

##Appending arrays
@c = (@a, @b);

##Reversing an array
@arr = reverse (@arr);

splice function

It is used to inseret the elements of one array into the middle of another array.

Computing Union, intersection, or Diffrences of unique lists...

@a = (1, 3, 6, 7, 8);
@b = (2, 3, 5, 7, 9);

@union = @isect = ( );
%union = %isect = ( );

foreach $e (@a) {
$union{$e} = 1;
}

foreach $e2 (@b) {
if ($union{$e2} ) {
$isect {$e2} = 1;
}
$union{$e2} = 1;
}

@union = keys %union;
@isect = keys %isect;

Finding elements in one array but not other...

@A = qw(a, b, c, d, e);
@B = qw(a, b, e);

@Aonly= ();
%seen = ();

foreach $ele (@B) {
%seen{$ele} = 1;
}

foreach $ele (@A) {
unless ($seen{$ele)) {
###push that element if not seen already.
push (@Aonly, $ele);
}
}

######2nd method##

@seen{@B} = ();

foreach $ele (@A) {
### push that element if it doesn't exist in @B or not seen in @B
push (@Aonly, $lele) unless exists $seen{$ele} ;
}

Extracting unique elements from a list...

@list = qw(a, b, c, d, a, e, b);

%seen = ( );
@uniq = ( );

foreach $item (@list) {
unless ( $seen{$item} ) {
#### we have not seen this item before
$seen{$item} = 1;
push(@uniq, $item);
}
}

##########faster method ####

foreach $item (@list) {
push (@uniq , $item) unless $seen{$item}++;
}

######simple method####
@uniq = sort -u @list;