[SYCL] Support extra environment variables in LIT (#3598)

Add ability to set extra environment variables in CMake (LIT_EXTRA_ENVIRONMENT)
or LIT (extra_environment) parameters. The value should contain comma separated
VARIABLE=VALUE pairs.

Author: vladimirlaz

sycl/test/lit.cfg.py

@@ -35,9 +35,23 @@
 # test_exec_root: The root path where tests should be run.
 config.test_exec_root = os.path.join(config.sycl_obj_root, 'test')
 
+llvm_config.use_clang()
+
 # Propagate some variables from the host environment.
 llvm_config.with_system_environment(['PATH', 'OCL_ICD_FILENAMES', 'SYCL_DEVICE_ALLOWLIST', 'SYCL_CONFIG_FILE_NAME'])
 
+# Propagate extra environment variables
+if config.extra_environment:
+    lit_config.note("Extra environment variables")
+    for env_pair in config.extra_environment.split(','):
+        [var,val]=env_pair.split("=")
+        if val:
+           llvm_config.with_environment(var,val)
+           lit_config.note("\t"+var+"="+val)
+        else:
+           lit_config.note("\tUnset "+var)
+           llvm_config.with_environment(var,"")
+
 # Configure LD_LIBRARY_PATH or corresponding os-specific alternatives
 # Add 'libcxx' feature to filter out all SYCL abi tests when SYCL runtime
 # is built with llvm libcxx. This feature is added for Linux only since MSVC
@@ -76,8 +90,6 @@
 config.substitutions.append( ('%llvm_build_lib_dir',  config.llvm_build_lib_dir ) )
 config.substitutions.append( ('%llvm_build_bin_dir',  config.llvm_build_bin_dir ) )
 
-llvm_config.use_clang()
-
 llvm_config.add_tool_substitutions(['llvm-spirv'], [config.sycl_tools_dir])
 
 config.substitutions.append( ('%RUN_ON_HOST', "env SYCL_DEVICE_FILTER=host ") )

sycl/test/lit.site.cfg.py.in

@@ -23,6 +23,7 @@ config.llvm_enable_projects = "@LLVM_ENABLE_PROJECTS@"
 
 config.sycl_threads_lib = '@SYCL_THREADS_LIB@'
 config.sycl_use_libcxx = '@SYCL_USE_LIBCXX@'
+config.extra_environment = lit_config.params.get("extra_environment", "@LIT_EXTRA_ENVIRONMENT@")
 
 import lit.llvm
 lit.llvm.initialize(lit_config, config)

sycl/test/on-device/lit.cfg.py

@@ -40,6 +40,18 @@
 # Propagate some variables from the host environment.
 llvm_config.with_system_environment(['PATH', 'OCL_ICD_FILENAMES', 'SYCL_DEVICE_ALLOWLIST', 'SYCL_CONFIG_FILE_NAME'])
 
+# Propagate extra environment variables
+if config.extra_environment:
+    lit_config.note("Extra environment variables")
+    for env_pair in config.extra_environment.split(','):
+        [var,val]=env_pair.split("=")
+        if val:
+           llvm_config.with_environment(var,val)
+           lit_config.note("\t"+var+"="+val)
+        else:
+           lit_config.note("\tUnset "+var)
+           llvm_config.with_environment(var,"")
+
 # Configure LD_LIBRARY_PATH or corresponding os-specific alternatives
 if platform.system() == "Linux":
     config.available_features.add('linux')

sycl/test/on-device/lit.site.cfg.py.in

@@ -25,6 +25,7 @@ config.level_zero_include_dir = lit_config.params.get('LEVEL_ZERO_INCLUDE_DIR',
 config.llvm_enable_projects = "@LLVM_ENABLE_PROJECTS@"
 
 config.sycl_threads_lib = '@SYCL_THREADS_LIB@'
+config.extra_environment = lit_config.params.get("extra_environment", "@LIT_EXTRA_ENVIRONMENT@")
 
 import lit.llvm
 lit.llvm.initialize(lit_config, config)