Add optional SEED=n command line option to Makefile, and -S n command line option to test scripts, for deterministic regression tests.

tests/realmath/generate.py

@@ -1,5 +1,6 @@
 #!/usr/bin/env python3
 
+import argparse
 import sys
 import random
 from contextlib import contextmanager
@@ -36,7 +37,16 @@ def random_expression(depth = 3, maxparam = 0):
         return op + '(' + recursion() + ', ' + recursion() + ')'
     raise
 
-for idx in range(100):
+parser = argparse.ArgumentParser(formatter_class = argparse.ArgumentDefaultsHelpFormatter)
+parser.add_argument('-S', '--seed',  type = int, help = 'seed for PRNG')
+parser.add_argument('-c', '--count', type = int, default = 100, help = 'number of test cases to generate')
+args = parser.parse_args()
+
+if args.seed is not None:
+    print("PRNG seed: %d" % args.seed)
+    random.seed(args.seed)
+
+for idx in range(args.count):
     with open('temp/uut_%05d.v' % idx, 'w') as f:
         with redirect_stdout(f):
             print('module uut_%05d(output [63:0] %s);\n' % (idx, ', '.join(['y%02d' % i for i in range(100)])))

tests/realmath/run-test.sh

@@ -1,14 +1,26 @@
 #!/bin/bash
 set -e
 
+OPTIND=1
+count=100
+seed=""    # default to no seed specified
+while getopts "c:S:" opt
+do
+    case "$opt" in
+	c) count="$OPTARG" ;;
+	S) seed="-S $OPTARG" ;;
+    esac
+done
+shift "$((OPTIND-1))"
+
 rm -rf temp
 mkdir -p temp
 echo "generating tests.."
-python3 generate.py
+python3 generate.py -c $count $seed
 
 cd temp
 echo "running tests.."
-for ((i = 0; i < 100; i++)); do
+for ((i = 0; i < $count; i++)); do
 	echo -n "[$i]"
 	idx=$( printf "%05d" $i )
 	../../../yosys -qq uut_${idx}.ys