Add options for base dir and redirecting files to IRT open resource and use it.

pnacl/driver/pnacl-translate.py

Index: pnacl/driver/pnacl-translate.py
diff --git a/pnacl/driver/pnacl-translate.py b/pnacl/driver/pnacl-translate.py
index b03eb7cfe62e8abb9cb0cfc34e3c25a31dcd7fc0..3521baa8e94ad4b6bb8250f9b922872b93d780b6 100755
--- a/pnacl/driver/pnacl-translate.py
+++ b/pnacl/driver/pnacl-translate.py
@@ -353,15 +353,13 @@ def main(argv):
     # The x86->arm emulator is very flaky when threading is used, so don't
     # do module splitting when using it.
     env.set('SPLIT_MODULE', '1')
-  else:
-    modules = env.getone('SPLIT_MODULE')
-    if modules != '1':
-      env.append('LLC_FLAGS_EXTRA', '-split-module=' + modules)
-      env.append('LD_FLAGS', '-split-module=' + modules)
-    if not env.getbool('SANDBOXED') and env.getbool('STREAM_BITCODE'):
-      # Do not set -streaming-bitcode for sandboxed mode, because it is already
-      # in the default command line.
-      env.append('LLC_FLAGS_EXTRA', '-streaming-bitcode')
+  modules = env.getone('SPLIT_MODULE')
+  env.append('LLC_FLAGS_EXTRA', '-split-module=' + modules)
+  env.append('LD_FLAGS', '-split-module=' + modules)
+  # Do not set -streaming-bitcode for sandboxed mode, because it is already
+  # in the default command line.
+  if not env.getbool('SANDBOXED') and env.getbool('STREAM_BITCODE'):
+    env.append('LLC_FLAGS_EXTRA', '-streaming-bitcode')
 
   # If there's a bitcode file, translate it now.
   tng = driver_tools.TempNameGen(inputs + bcfiles, output)