[runtimes] Move libunwind, libc++abi and libc++ to lib/$target/c++ and include/c++

This change is a consequence of the discussion in "RFC: Place libs in
Clang-dedicated directories", specifically the suggestion that
libunwind, libc++abi and libc++ shouldn't be using Clang resource
directory. Tools like clangd make this assumption, but this is
currently not true for the LLVM_ENABLE_PER_TARGET_RUNTIME_DIR build.
This change addresses that by moving the output of these libraries to
lib/$target/c++ and include/c++ directories, leaving resource directory
only for compiler-rt runtimes and Clang builtin headers.

Differential Revision: https://reviews.llvm.org/D59168

git-svn-id: https://llvm.org/svn/llvm-project/libunwind/trunk@361432 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 8d48167..65cd5b2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -188,20 +188,25 @@
        ${PACKAGE_VERSION})
 
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
-  set(DEFAULT_INSTALL_PREFIX lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}/${LLVM_DEFAULT_TARGET_TRIPLE}/)
-  set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION}/${LLVM_DEFAULT_TARGET_TRIPLE}/lib${LIBUNWIND_LIBDIR_SUFFIX})
+  set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/${LLVM_DEFAULT_TARGET_TRIPLE}/c++)
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LLVM_LIBDIR_SUFFIX}/${LLVM_DEFAULT_TARGET_TRIPLE}/c++)
+  if(LIBCXX_LIBDIR_SUBDIR)
+    string(APPEND LIBUNWIND_LIBRARY_DIR /${LIBUNWIND_LIBDIR_SUBDIR})
+    string(APPEND LIBUNWIND_INSTALL_LIBRARY_DIR /${LIBUNWIND_LIBDIR_SUBDIR})
+  endif()
 elseif(LLVM_LIBRARY_OUTPUT_INTDIR)
   set(LIBUNWIND_LIBRARY_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LIBUNWIND_LIBDIR_SUFFIX})
 else()
   set(LIBUNWIND_LIBRARY_DIR ${CMAKE_BINARY_DIR}/lib${LIBUNWIND_LIBDIR_SUFFIX})
+  set(LIBUNWIND_INSTALL_LIBRARY_DIR lib${LIBUNWIND_LIBDIR_SUFFIX})
 endif()
 
 set(CMAKE_ARCHIVE_OUTPUT_DIRECTORY ${LIBUNWIND_LIBRARY_DIR})
 set(CMAKE_LIBRARY_OUTPUT_DIRECTORY ${LIBUNWIND_LIBRARY_DIR})
 set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${LIBUNWIND_LIBRARY_DIR})
 
-set(LIBUNWIND_INSTALL_PREFIX ${DEFAULT_INSTALL_PREFIX} CACHE STRING
-    "Define libunwind destination prefix.")
+set(LIBUNWIND_INSTALL_PREFIX "" CACHE STRING "Define libunwind destination prefix.")
 
 set(LIBUNWIND_C_FLAGS "")
 set(LIBUNWIND_CXX_FLAGS "")

src/CMakeLists.txt

diff --git a/src/CMakeLists.txt b/src/CMakeLists.txt
index 9ca773b..572c823 100644
--- a/src/CMakeLists.txt
+++ b/src/CMakeLists.txt
@@ -159,8 +159,8 @@
 
 if (LIBUNWIND_INSTALL_LIBRARY)
   install(TARGETS ${LIBUNWIND_INSTALL_TARGETS}
-    LIBRARY DESTINATION ${LIBUNWIND_INSTALL_PREFIX}lib${LIBUNWIND_LIBDIR_SUFFIX} COMPONENT unwind
-    ARCHIVE DESTINATION ${LIBUNWIND_INSTALL_PREFIX}lib${LIBUNWIND_LIBDIR_SUFFIX} COMPONENT unwind)
+    LIBRARY DESTINATION ${LIBUNWIND_INSTALL_PREFIX}${LIBUNWIND_INSTALL_LIBRARY_DIR} COMPONENT unwind
+    ARCHIVE DESTINATION ${LIBUNWIND_INSTALL_PREFIX}${LIBUNWIND_INSTALL_LIBRARY_DIR} COMPONENT unwind)
 endif()
 
 if (NOT CMAKE_CONFIGURATION_TYPES AND LIBUNWIND_INSTALL_LIBRARY)