1 files changed, 116 insertions, 0 deletions
diff --git a/src/relooper/fuzzer.py b/src/relooper/fuzzer.py
new file mode 100644
index 00000000..887eab3b
--- /dev/null
+++ b/src/relooper/fuzzer.py
@@ -0,0 +1,116 @@
+
+import random, subprocess, difflib
+
+while True:
+  # Random decisions
+  num = random.randint(2, 250)
+  density = random.random() * random.random()
+  decisions = [random.randint(1, num*20) for x in range(num*3)]
+  branches = [0]*num
+  defaults = [0]*num
+  for i in range(num):
+    b = set([])
+    bs = random.randint(1, max(1, round(density*random.random()*(num-1))))
+    for j in range(bs):
+      b.add(random.randint(1, num-1))
+    b = list(b)
+    defaults[i] = random.choice(b)
+    b.remove(defaults[i])
+    branches[i] = b
+  print num, density
+
+  for temp in ['fuzz', 'fuzz.fast.js', 'fuzz.slow.js', 'fuzz.cpp']:
+    try:
+      os.unlink(temp)
+    except:
+      pass
+
+  # parts
+  entry = '''print('entry'); var label; var state; var decisions = %s; var index = 0; function check() { if (index == decisions.length) throw 'HALT'; return decisions[index++] }''' % str(decisions)
+
+  slow = entry + '\n'
+  for i in range(len(branches[0])):
+    if i > 0: slow += 'else '
+    b = branches[0]
+    slow += 'if (state %% %d == %d) { label = %d; }\n' % (len(b)+1, i, b[i]) # TODO: split range 1-n into these options
+  if len(branches[0]): slow += 'else '
+  slow += 'label = %d;\n' % defaults[0]
+
+  slow += '''
+while(1) switch(label) {
+'''
+
+  fast = '''
+
+#include <stdlib.h>
+#include "Relooper.h"
+
+int main() {
+  char *buffer = (char*)malloc(10*1024*1024);
+  Relooper::SetOutputBuffer(buffer, 10*1024*1024);
+'''
+
+  for i in range(1, num):
+    slow += '  case %d: print(%d); state = check(); \n' % (i, i)
+    b = branches[i]
+    for j in range(len(b)):
+      slow += '    if (state %% %d == %d) { label = %d; break }\n' % (len(b)+1, j, b[j]) # TODO: split range 1-n into these options
+    slow += '    label = %d; break\n' % defaults[i]
+
+  for i in range(num):
+    if i == 0:
+      fast += '''
+  Block *b%d = new Block("%s");
+''' % (i, entry)
+    else:
+      fast += '''  Block *b%d = new Block("print(%d); state = check();%s");
+''' % (i, i, '// ' + ('.' * int(random.expovariate(0.5/num))))
+
+  for i in range(num):
+    b = branches[i]
+    for j in range(len(b)):
+      fast += '''  b%d->AddBranchTo(b%d, "state %% %d == %d");
+''' % (i, b[j], len(b)+1, j)
+    fast += '''  b%d->AddBranchTo(b%d, NULL);
+''' % (i, defaults[i])
+
+  fast += '''
+  Relooper r;
+'''
+
+  for i in range(num):
+    fast += '''  r.AddBlock(b%d);
+''' % i
+
+  fast += '''
+  r.Calculate(b0);
+  printf("\\n\\n");
+  r.Render();
+
+  puts(buffer);
+
+  return 1;
+}
+'''
+
+  slow += '}'
+
+  open('fuzz.slow.js', 'w').write(slow)
+  open('fuzz.cpp', 'w').write(fast)
+  print '_'
+  slow_out = subprocess.Popen(['/home/alon/Dev/mozilla-central/js/src/fast/js', '-m', '-n', 'fuzz.slow.js'], stdout=subprocess.PIPE).communicate()[0]
+
+  print '.'
+  subprocess.call(['g++', 'fuzz.cpp', 'Relooper.o', '-o', 'fuzz', '-g'])
+  print '*'
+  subprocess.call(['./fuzz'], stdout=open('fuzz.fast.js', 'w'))
+  print '-'
+  fast_out = subprocess.Popen(['/home/alon/Dev/mozilla-central/js/src/fast/js', '-m', '-n', 'fuzz.fast.js'], stdout=subprocess.PIPE).communicate()[0]
+  print
+
+  if slow_out != fast_out:
+    print ''.join([a.rstrip()+'\n' for a in difflib.unified_diff(slow_out.split('\n'), fast_out.split('\n'), fromfile='slow', tofile='fast')])
+    assert False
+
+  #break
+