Add option to force filetype=asm for testing

tests_lit/lit.cfg

 # -*- Python -*-
 # Taken from utils/lit/tests in the LLVM tree and hacked together to support
 # our tests.
 #
 # Note: This configuration has simple commands to run Subzero's translator.
 # They have the form %X2i (i.e. %p2i, %l2i, and %lc2i) where X is defined
 # as follows:
 #
 #   p : Run Subzero's translator, building ICE from PNaCl bitcode directly.
 #   l : Run Subzero's translator, converting the .ll file to a PNaCl bitcode
@@ skipping 71 matching lines @@
 if_atts_cmd = if_atts + ['--have=' + att for att in pnacl_sz_atts]
 ifl2i_atts_cmd = if_atts + [if_cond_flag('allow_llvm_ir' in pnacl_sz_atts),
                             '--command']
 iflc2i_atts_cmd = if_atts + [if_cond_flag('allow_llvm_ir_as_input'
                                           in pnacl_sz_atts), '--command']
 
 # Base command for running pnacl-sz
 pnacl_sz_cmd = [os.path.join(pydir, 'run-pnacl-sz.py'),
                 '--pnacl-sz', pnacl_sz_tool,
                 '--pnacl-bin-path', pnaclbinpath]
+if 'FORCEASM' in lit_config.params:
+  pnacl_sz_cmd += ['--forceasm']
 
 # Run commands only if corresponding build attributes apply, including
 # for each compiler setup.
 config.substitutions.append(('%ifp', ' '))
 config.substitutions.append(('%iflc', ' '.join(iflc2i_atts_cmd)))
 config.substitutions.append(('%ifl', ' '.join(ifl2i_atts_cmd)))
 config.substitutions.append(('%if', ' '.join(if_atts_cmd)))
 
 # Translate LLVM source for each compiler setup.
 config.substitutions.append(('%p2i', ' '.join(pnacl_sz_cmd)))
@@ skipping 30 matching lines @@
 config.available_features.add("python%d.%d" % (sys.version_info[0],
                                                sys.version_info[1]))
 
 # Debugging output
 def dbg(s):
   print '[DBG] %s' % s
 
 dbg('bin_root = %s' % bin_root)
 dbg('pnaclbinpath = %s' % pnaclbinpath)
 dbg("Build attributes = %s" % pnacl_sz_atts)