Added global option for license queuing

sweep.bash

@@ -47,6 +47,13 @@ RETIME_ENABLE="YES"
 # idealy be set to min{ Computer Cores, Design Compiler Licenses }.
 MAX_CONCURRENCY=12
 
+# Wait for appropriate Design Compiler licenses when the required licenses are
+# currently already in use by other Design Compiler instances. This enables
+# Design Compiler License Queuing. Setting this option to 'NO' can make you
+# miss sweep points if all available licenses are already in use by other Design
+# Compiler instances. Set to either 'YES' or 'NO' (note the CAPITALIZATION).
+WAIT_FOR_LICENSE="YES"
+
 # String that will be appended to the top sweep directory name. Could, for
 # example, be used to append technology, corrner or other vital info to the 
 # sweep directory name. Leave blank if unused.
@@ -127,18 +134,24 @@ function generate_synthesis_script() {
 # access any unexported items (variables, functions, etc).
 function run_design_compiler() {
 
-    # Change directory to design directory.
+    # Change active directory to design directory.
     local design_directory="$1"
     cd "$design_directory" || exit 1
 
     # Get time of sweep start.
     start_time="$(date +"%H:%M:%S")"
 
+    # Activate Design Compiler License Queuing if requiered in global settings.
+    if [ ${WAIT_FOR_LICENSE} = "YES" ]; then
+        export SNPSLMD_QUEUE="true"
+    fi
+
     # Source the automatically generated design options file. This file contains
     # 'period' and 'design'generics'.
     # shellcheck disable=SC1091
     source .design_options.sh
 
+    # Display sweep start.
     if [ "$design_generics" = "" ]; then
         echo "[ PID: $$ ]: $start_time, starting synthesis: '$DESIGN_NAME'" \
              "@ $period $PERIOD_DIM."
@@ -180,6 +193,7 @@ function sigterm_handler() {
 export -f run_design_compiler
 export DESIGN_NAME
 export PERIOD_DIM
+export WAIT_FOR_LICENSE
 
 # Sanity checks for the global settings.
 if [ -z "$CLOCK_NAME" ]; then
@@ -208,6 +222,10 @@ if ! [[ "$RETIME_ENABLE" =~ ^(YES)|(NO)$ ]]; then
     echo "Error: \$RETIME_ENABLE not in { "YES", "NO" }."
     exit 1
 fi
+if ! [[ "${WAIT_FOR_LICENSE}" =~ ^(YES)|(NO)$ ]]; then
+    echo "Error: \$WAIT_FOR_LICENSE not in { "YES", "NO" }."
+    exit 1
+fi
 
 # Assure all periods are in numeric format, with max one decimal delimiter.
 for period in "${PERIODS[@]}"; do