Resubmit "[lit] Force site configs to run before source-tree configs"

This is a resubmission of r313270.  It broke standalone builds of
compiler-rt because we were not correctly generating the llvm-lit
script in the standalone build directory.

The fixes incorporated here attempt to find llvm/utils/llvm-lit
from the source tree returned by llvm-config.  If present, it
will generate llvm-lit into the output directory.  Regardless,
the user can specify -DLLVM_EXTERNAL_LIT to point to a specific
lit.py on their file system.  This supports the use case of
someone installing lit via a package manager.  If it cannot find
a source tree, and -DLLVM_EXTERNAL_LIT is either unspecified or
invalid, then we print a warning that tests will not be able
to run.

Differential Revision: https://reviews.llvm.org/D37756

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@313407 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 22 insertions, 43 deletions

diff --git a/utils/llvm-lit/CMakeLists.txt b/utils/llvm-lit/CMakeLists.txt
index 4b10354cfde..670175c8185 100644
--- a/utils/llvm-lit/CMakeLists.txt
+++ b/utils/llvm-lit/CMakeLists.txt
@@ -1,12 +1,13 @@
-if (WIN32 AND NOT CYGWIN)
-  # llvm-lit needs suffix.py for multiprocess to find a main module.
-  set(suffix .py)
-endif ()
-set(llvm_lit_path ${LLVM_RUNTIME_OUTPUT_INTDIR}/llvm-lit${suffix})
+get_property(LLVM_LIT_CONFIG_MAP GLOBAL PROPERTY LLVM_LIT_CONFIG_MAP)
+
+get_llvm_lit_path(LIT_BASE_DIR LIT_FILE_NAME)
+
+set(LLVM_SOURCE_DIR ${LLVM_MAIN_SRC_DIR})
 
 if(NOT "${CMAKE_CFG_INTDIR}" STREQUAL ".")
   foreach(BUILD_MODE ${CMAKE_CONFIGURATION_TYPES})
-    string(REPLACE ${CMAKE_CFG_INTDIR} ${BUILD_MODE} bi ${llvm_lit_path})
+    string(REPLACE ${CMAKE_CFG_INTDIR} ${BUILD_MODE} bi ${LIT_BASE_DIR})
+    set(bi "${bi}/${LIT_FILE_NAME}")
     configure_file(
       llvm-lit.in
       ${bi}
@@ -16,6 +17,6 @@ else()
   set(BUILD_MODE .)
   configure_file(
     llvm-lit.in
-    ${llvm_lit_path}
+    ${LIT_BASE_DIR}/${LIT_FILE_NAME}
     )
 endif()
diff --git a/utils/llvm-lit/llvm-lit.in b/utils/llvm-lit/llvm-lit.in
index 08a2a670b21..efad97ade7e 100755
--- a/utils/llvm-lit/llvm-lit.in
+++ b/utils/llvm-lit/llvm-lit.in
@@ -3,6 +3,15 @@
 import os
 import sys
 
+config_map = {}
+
+def map_config(source_dir, site_config):
+    global config_map
+    source_dir = os.path.normpath(source_dir)
+    source_dir = os.path.normcase(source_dir)
+    site_config = os.path.normpath(site_config)
+    config_map[source_dir] = site_config
+
 # Variables configured at build time.
 llvm_source_root = "@LLVM_SOURCE_DIR@"
 llvm_obj_root = "@LLVM_BINARY_DIR@"
@@ -12,42 +21,11 @@ sys.path.insert(0, os.path.join(llvm_source_root, 'utils', 'lit'))
 
 # Set up some builtin parameters, so that by default the LLVM test suite
 # configuration file knows how to find the object tree.
-builtin_parameters = {
-    'build_mode' : "@BUILD_MODE@",
-    'llvm_site_config' : os.path.join(llvm_obj_root, 'test', 'lit.site.cfg'),
-    'llvm_unit_site_config' : os.path.join(llvm_obj_root, 'test', 'Unit',
-                                           'lit.site.cfg')
-    }
-
-clang_obj_root = os.path.join(llvm_obj_root, 'tools', 'clang')
-
-if os.path.exists(clang_obj_root):
-    builtin_parameters['clang_site_config'] = \
-        os.path.join(clang_obj_root, 'test', 'lit.site.cfg')
-    clang_tools_extra_obj_root = os.path.join(clang_obj_root, 'tools', 'extra')
-    if os.path.exists(clang_tools_extra_obj_root):
-        builtin_parameters['clang_tools_extra_site_config'] = \
-            os.path.join(clang_tools_extra_obj_root, 'test', 'lit.site.cfg')
-
-lld_obj_root = os.path.join(llvm_obj_root, 'tools', 'lld')
-if os.path.exists(lld_obj_root):
-    builtin_parameters['lld_site_config'] = \
-        os.path.join(lld_obj_root, 'test', 'lit.site.cfg')
-
-compilerrt_obj_root = os.path.join(llvm_obj_root, 'projects', 'compiler-rt')
-if os.path.exists(compilerrt_obj_root):
-    builtin_parameters['compilerrt_site_basedir'] = \
-            os.path.join(compilerrt_obj_root, 'test')
-
-libcxx_obj_root = os.path.join(llvm_obj_root, 'projects', 'libcxx')
-if os.path.exists(libcxx_obj_root):
-    builtin_parameters['libcxx_site_config'] = \
-        os.path.join(libcxx_obj_root, 'test', 'lit.site.cfg')
-
-libcxxabi_obj_root = os.path.join(llvm_obj_root, 'projects', 'libcxxabi')
-if os.path.exists(libcxxabi_obj_root):
-    builtin_parameters['libcxxabi_site_config'] = \
-        os.path.join(libcxxabi_obj_root, 'test', 'lit.site.cfg')
+builtin_parameters = { 'build_mode' : "@BUILD_MODE@" }
+
+@LLVM_LIT_CONFIG_MAP@
+
+builtin_parameters['config_map'] = config_map
 
 if __name__=='__main__':
     from lit.main import main