New fuzzer (#1126)

This adds a new method of fuzzing, "translate to fuzz" which means we consider the input to be a stream of data that we translate into a valid wasm module. It's sort of like a random seed for a process that creates a random wasm module. By using the input that way, we can explore the space of valid wasm modules quickly, and it makes afl-fuzz integration easy.

Also adds a "fuzz binary" option which is similar to "fuzz execution". It makes wasm-opt not only execute the code before and after opts, but also write to binary and read from it, helping to fuzz the binary format.

1 files changed, 8 insertions, 1 deletions

diff --git a/auto_update_tests.py b/auto_update_tests.py
index 7aab8ea4e..fd5999cad 100755
--- a/auto_update_tests.py
+++ b/auto_update_tests.py
@@ -45,7 +45,6 @@ for asm in sorted(os.listdir('test')):
           cmd += ['--source-map', os.path.join('test', wasm + '.map'), '-o', 'a.wasm']
           run_command(cmd)
 
-
 for dot_s_dir in ['dot_s', 'llvm_autogenerated']:
   for s in sorted(os.listdir(os.path.join('test', dot_s_dir))):
     if not s.endswith('.s'): continue
@@ -102,6 +101,14 @@ for t in sorted(os.listdir(os.path.join('test', 'passes'))):
       cmd = WASM_OPT + opts + ['split.wast', '--print']
       actual += run_command(cmd)
     with open(os.path.join('test', 'passes', passname + ('.bin' if binary else '') + '.txt'), 'w') as o: o.write(actual)
+    if 'emit-js-wrapper' in t:
+      with open('a.js') as i:
+        with open(t + '.js', 'w') as o:
+          o.write(i.read())
+    if 'emit-spec-wrapper' in t:
+      with open('a.wat') as i:
+        with open(t + '.wat', 'w') as o:
+          o.write(i.read())
 
 print '\n[ checking wasm-opt -o notation... ]\n'