[llvm] 45526d2 - [CMAKE] Provide default location for llvm-lit for out-of-tree users.

[Stephen Neuendorffer via llvm-commits]

Author: Stephen Neuendorffer
Date: 2020-04-22T15:13:23-07:00
New Revision: 45526d29a5b2cf126b83ada3991921970007d16f

URL: https://github.com/llvm/llvm-project/commit/45526d29a5b2cf126b83ada3991921970007d16f
DIFF: https://github.com/llvm/llvm-project/commit/45526d29a5b2cf126b83ada3991921970007d16f.diff

LOG: [CMAKE] Provide default location for llvm-lit for out-of-tree users.

Several external build users contain some heuristics for finding llvm-lit.
There are several cases we need to worry about:
- External builds against a build tree (with LLVM_BUILD_UTILS)
- External builds against an install tree (with LLMV_BUILD_UTIL
  and LLVM_INSTALL_UTILS)
- External builds against some location which doesn't have an
  llvm-lit, but llvm-lit is available through some other means, such
  as an available source tree, or a packager provided llvm-lit.

For the third case, LLVM_EXTERNAL_LIT suffices, but in other cases
there's no standard way to find llvm-lit.  It seems like each user
cooks their own heuristics:

- clang tries to look in the LLVM source tree, and failing that falls
  back to looking for a packaged llvm-lit.
- libcxx tries to look in the LLVM source tree, which might come from
  llvm-config or be explicitly specified.

This patch is a first stop to solving this by providing a default location
for llvm-lit using LLVM_DEFAULT_EXTERNAL_LIT.  The expectation is that
future patches can clean up users like clang and libcxx to rely
on this mechanism for out-of-tree builds.

Differential Revision: https://reviews.llvm.org/D77110

Added: 
    

Modified: 
    llvm/cmake/modules/CMakeLists.txt
    llvm/cmake/modules/LLVMConfig.cmake.in

Removed: 
    


################################################################################
diff  --git a/llvm/cmake/modules/CMakeLists.txt b/llvm/cmake/modules/CMakeLists.txt
index af757d6199a8..4bb03b63122b 100644
--- a/llvm/cmake/modules/CMakeLists.txt
+++ b/llvm/cmake/modules/CMakeLists.txt
@@ -54,6 +54,11 @@ set(LLVM_CONFIG_CMAKE_DIR "${CMAKE_CURRENT_SOURCE_DIR}")
 set(LLVM_CONFIG_BINARY_DIR "${LLVM_BINARY_DIR}")
 set(LLVM_CONFIG_TOOLS_BINARY_DIR "${LLVM_TOOLS_BINARY_DIR}")
 
+# Generate a default location for lit
+if (LLVM_BUILD_UTILS)
+  set(LLVM_CONFIG_DEFAULT_EXTERNAL_LIT "${LLVM_CONFIG_TOOLS_BINARY_DIR}/llvm-lit")
+endif()
+
 if (LLVM_LINK_LLVM_DYLIB)
   set(LLVM_CONFIG_LINK_LLVM_DYLIB
       "set(LLVM_LINK_LLVM_DYLIB ${LLVM_LINK_LLVM_DYLIB})")
@@ -103,6 +108,12 @@ set(LLVM_CONFIG_LIBRARY_DIRS "\${LLVM_INSTALL_PREFIX}/lib\${LLVM_LIBDIR_SUFFIX}"
 set(LLVM_CONFIG_CMAKE_DIR "\${LLVM_INSTALL_PREFIX}/${LLVM_INSTALL_PACKAGE_DIR}")
 set(LLVM_CONFIG_BINARY_DIR "\${LLVM_INSTALL_PREFIX}")
 set(LLVM_CONFIG_TOOLS_BINARY_DIR "\${LLVM_INSTALL_PREFIX}/bin")
+
+# Generate a default location for lit
+if (LLVM_INSTALL_UTILS AND LLVM_BUILD_UTILS)
+  set(LLVM_CONFIG_DEFAULT_EXTERNAL_LIT "${LLVM_CONFIG_TOOLS_BINARY_DIR}/llvm-lit")
+endif()
+
 set(LLVM_CONFIG_EXPORTS_FILE "\${LLVM_CMAKE_DIR}/LLVMExports.cmake")
 set(LLVM_CONFIG_EXPORTS "${LLVM_EXPORTS}")
 configure_file(

diff  --git a/llvm/cmake/modules/LLVMConfig.cmake.in b/llvm/cmake/modules/LLVMConfig.cmake.in
index 87684ecba0f5..fa6082c7e397 100644
--- a/llvm/cmake/modules/LLVMConfig.cmake.in
+++ b/llvm/cmake/modules/LLVMConfig.cmake.in
@@ -93,6 +93,7 @@ set(LLVM_CMAKE_DIR "@LLVM_CONFIG_CMAKE_DIR@")
 set(LLVM_BINARY_DIR "@LLVM_CONFIG_BINARY_DIR@")
 set(LLVM_TOOLS_BINARY_DIR "@LLVM_CONFIG_TOOLS_BINARY_DIR@")
 set(LLVM_TOOLS_INSTALL_DIR "@LLVM_TOOLS_INSTALL_DIR@")
+set(LLVM_DEFAULT_EXTERNAL_LIT "@LLVM_CONFIG_DEFAULT_EXTERNAL_LIT@")
 set(LLVM_HAVE_OPT_VIEWER_MODULES @LLVM_HAVE_OPT_VIEWER_MODULES@)
 set(LLVM_CONFIGURATION_TYPES @CMAKE_CONFIGURATION_TYPES@)
 set(LLVM_ENABLE_SHARED_LIBS @BUILD_SHARED_LIBS@)