Add Subzero to test scripts.

tools/toolchain_tester/torture_test.py

Index: tools/toolchain_tester/torture_test.py
diff --git a/tools/toolchain_tester/torture_test.py b/tools/toolchain_tester/torture_test.py
index 3e29934cff4340dd76db84ec40172ae60606a4fb..8d58652a9d0f2bdea4166e9c48c3adce9cedbd6f 100755
--- a/tools/toolchain_tester/torture_test.py
+++ b/tools/toolchain_tester/torture_test.py
@@ -92,6 +92,9 @@ def run_torture(status, compiler, platform, extra_args):
   if compiler == 'pnacl':
     # O3_O0 is clang -O3 followed by pnacl-translate -O0
     optmodes = ['O0', 'O3', 'O0_O0', 'O3_O0']
+    if platform == 'x86-32':
+      # Add some extra Subzero configurations.

[Jim Stichnoth, 2015/03/25 01:17:09]

This adds two new configurations, 50% more runtime.  Should we drop one of the
old configs, like O0_O0?

[jvoung (off chromium), 2015/03/25 18:41:38]

Maybe... but O0f_O2b might be the weirder config. On the other hand, it could
tickle weird optimization bugs in the backend from mixing O0/O2 which we may or
may not be interested in fixing.

O0f_O0b might be more representative of debugging.

[Jim Stichnoth, 2015/03/25 20:13:17]

OK.  For now, I just left a TODO about possible pruning.

+      optmodes.extend(['O3_sz', 'O3_O0_sz'])
   else:
     optmodes = ['O0', 'O3']
   for optmode in optmodes: