[test] Use LD_LIBRARY_PATH to ensure that a new lib is used (#1989) (#1990)

Add the library `BINARY_DIR` to `LD_LIBRARY_PATH` to ensure that
the freshly built `libLLVMSPIRVLib.so` is tested.  Otherwise, llvm-spirv
spawned by the test suite may use the previously installed
`libLLVMSPIRVLib.so`.

I have noticed the problem after rebuilding LLVM with
`-DLLVM_ENABLE_ASSSERTIONS=ON`.  This meant that the previous version
of `libLLVMSPIRVLib.so` now crashed, effectively causing the test suite
to fail incorrectly.

Signed-off-by: Michał Górny <mgorny@gentoo.org>

Author: mgorny

test/CMakeLists.txt

@@ -3,6 +3,7 @@ llvm_canonicalize_cmake_booleans(SPIRV_SKIP_DEBUG_INFO_TESTS)
 
 # required by lit.site.cfg.py.in
 get_target_property(LLVM_SPIRV_DIR llvm-spirv BINARY_DIR)
+get_target_property(LLVM_SPIRV_LIB_DIR LLVMSPIRVLib BINARY_DIR)
 set(LLVM_SPIRV_TEST_SOURCE_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 
 if(SPIRV_TOOLS_FOUND AND NOT SPIRV-Tools-tools_FOUND)

test/lit.cfg.py

@@ -76,6 +76,7 @@
 else:
     config.substitutions.append(('spirv-val', ':'))
 
+llvm_config.with_system_environment('LD_LIBRARY_PATH')
 if using_spirv_tools:
-    llvm_config.with_system_environment('LD_LIBRARY_PATH')
     llvm_config.with_environment('LD_LIBRARY_PATH', config.spirv_tools_lib_dir, append_path=True)
+llvm_config.with_environment('LD_LIBRARY_PATH', config.llvm_spirv_lib_dir, append_path=True)

test/lit.site.cfg.py.in

@@ -6,6 +6,7 @@ config.llvm_src_root = "@LLVM_SOURCE_DIR@"
 config.llvm_obj_root = "@LLVM_BINARY_DIR@"
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.llvm_spirv_dir = "@LLVM_SPIRV_DIR@"
+config.llvm_spirv_lib_dir = "@LLVM_SPIRV_LIB_DIR@"
 config.llvm_libs_dir = "@LLVM_LIBS_DIR@"
 config.llvm_shlib_dir = "@SHLIBDIR@"
 config.llvm_plugin_ext = "@LLVM_PLUGIN_EXT@"