Subzero: Auto-detect cmake versus autoconf LLVM build.

crosstest/lit.cfg

 import os
 import re
 import lit.formats
 
 config.name = 'subzero_crosstests'
 config.test_format = lit.formats.ShTest()
 config.suffixes = ['.xtest']
 config.test_source_root = os.path.dirname(__file__)
 config.test_exec_root = config.test_source_root
 
-llvmbintools = [r"\bFileCheck\b"]
-llvmbinpath = os.path.abspath(os.environ.get('LLVM_BIN_PATH'))
+pnaclbintools = [r"\bFileCheck\b"]
+pnaclbinpath = os.path.abspath(os.environ.get('PNACL_BIN_PATH'))
 
-for tool in llvmbintools:
+for tool in pnaclbintools:
   # The re.sub() line is adapted from one of LLVM's lit.cfg files.
   # Extract the tool name from the pattern.  This relies on the tool
   # name being surrounded by \b word match operators.  If the
   # pattern starts with "| ", include it in the string to be
   # substituted.
   substitution = re.sub(r"^(\\)?((\| )?)\W+b([0-9A-Za-z-_]+)\\b\W*$",
-                        r"\2" + llvmbinpath + "/" + r"\4",
+                        r"\2" + pnaclbinpath + "/" + r"\4",
                         tool)
   config.substitutions.append((tool, substitution))