[compiler-rt] Use ZLIB_FOUND not LLVM_ENABLE_ZLIB

[abrachet]

Summary

LLVM_ENABLE_ZLIB is set to On by default and does not imply that ZLIB
was actually found, only being set to FORCE_ON would imply that it was
found before control reached compiler-rt/test/CMakeLists.txt. Instead,
use ZLIB_FOUND which guarantees that zlib is available.

[phosek]

LGTM

compiler-rt/test/CMakeLists.txt

 # Needed for lit support in standalone builds.
 include(AddLLVM)
 
 option(COMPILER_RT_TEST_STANDALONE_BUILD_LIBS
   "When set to ON and testing in a standalone build, test the runtime \
   libraries built by this standalone build rather than the runtime libraries \
   shipped with the compiler (used for testing). When set to OFF and testing \
   in a standalone build, test the runtime libraries shipped with the compiler \
   (used for testing). This option has no effect if the compiler and this \
   build are configured to use the same runtime library path."
   ON)
 pythonize_bool(COMPILER_RT_TEST_STANDALONE_BUILD_LIBS)
 
 pythonize_bool(LLVM_ENABLE_EXPENSIVE_CHECKS)
+
+pythonize_bool(ZLIB_FOUND)
+
 configure_compiler_rt_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.common.configured.in
   ${CMAKE_CURRENT_BINARY_DIR}/lit.common.configured)
 
 # BlocksRuntime (and most of builtins) testsuites are not yet ported to lit.
 # add_subdirectory(BlocksRuntime)
 
 set(SANITIZER_COMMON_LIT_TEST_DEPS)

compiler-rt/test/lit.common.cfg.py

 if config.target_triple.startswith("ppc") or config.target_triple.startswith("powerpc"):
     config.available_features.add("ppc")
 
 if re.match(r"^x86_64.*-linux", config.target_triple):
     config.available_features.add("x86_64-linux")
 
 config.available_features.add("host-byteorder-" + sys.byteorder + "-endian")
 
-if config.have_zlib == "1":
+if config.have_zlib:
     config.available_features.add("zlib")
 
 # Use ugly construction to explicitly prohibit "clang", "clang++" etc.
 # in RUN lines.
 config.substitutions.append(
     (
         " clang",
         """\n\n*** Do not use 'clangXXX' in tests,

compiler-rt/test/lit.common.configured.in

 elif config.android:
   if config.target_arch == "i386":
     set_default("target_suffix", "-i686-android")
   else:
     set_default("target_suffix", "-%s-android" % config.target_arch)
 else:
   set_default("target_suffix", "-%s" % config.target_arch)
 
-set_default("have_zlib", "@LLVM_ENABLE_ZLIB@")
+set_default("have_zlib", @ZLIB_FOUND_PYBOOL@)
 set_default("libcxx_used", "@LLVM_LIBCXX_USED@")
 
 # LLVM tools dir can be passed in lit parameters, so try to
 # apply substitution.
 config.llvm_tools_dir = lit_config.substitute(config.llvm_tools_dir)
 config.clang = lit_config.substitute(config.clang)
 config.compiler_rt_libdir = lit_config.substitute(config.compiler_rt_libdir)
 
 if not os.path.exists(config.clang):
   lit_config.fatal("Can't find compiler on path %r" % config.clang)
 
 import lit.llvm
 lit.llvm.initialize(lit_config, config)
 
 # Setup attributes common for all compiler-rt projects.
 lit_config.load_config(config, "@COMPILER_RT_SOURCE_DIR@/test/lit.common.cfg.py")