Support for multiarch runtimes layout

This change adds a support for multiarch style runtimes layout, so in
addition to the existing layout where runtimes get installed to:

lib/clang/$version/lib/$os

Clang now allows runtimes to be installed to:

lib/clang/$version/$target/lib

This also includes libc++, libc++abi and libunwind; today those are
assumed to be in Clang library directory built for host, with the
new layout it is possible to install libc++, libc++abi and libunwind
into the runtime directory built for different targets.

The use of new layout is enabled by setting the
LLVM_ENABLE_RUNTIME_TARGET_DIR CMake variable and is supported by both
projects and runtimes layouts. The runtimes CMake build has been further
modified to use the new layout when building runtimes for multiple
targets.

Differential Revision: https://reviews.llvm.org/D45604

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@335809 91177308-0d34-0410-b5e6-96231b3b80d8

CMakeLists.txt

@@ -584,6 +584,9 @@ endif()
 set(LLVM_TARGET_TRIPLE_ENV CACHE STRING "The name of environment variable to override default target. Disabled by blank.")
 mark_as_advanced(LLVM_TARGET_TRIPLE_ENV)
 
+set(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR OFF CACHE BOOL
+  "Enable per-target runtimes directory")
+
 # All options referred to from HandleLLVMOptions have to be specified
 # BEFORE this include, otherwise options will not be correctly set on
 # first cmake run

runtimes/CMakeLists.txt

@@ -124,6 +124,9 @@ if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
     set(LLVM_RUNTIMES_PREFIX "${LLVM_RUNTIMES_TARGET}/")
   endif()
 
+  string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" CLANG_VERSION
+         ${PACKAGE_VERSION})
+
   foreach(entry ${runtimes})
     get_filename_component(projName ${entry} NAME)
 
@@ -133,12 +136,6 @@ if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
     # The subdirectories need to treat this as standalone builds
     set(${canon_name}_STANDALONE_BUILD On)
 
-    if(LLVM_RUNTIMES_TARGET)
-      if(NOT "${projName}" MATCHES "compiler-rt")
-        set(${canon_name}_INSTALL_PREFIX "lib/${LLVM_RUNTIMES_PREFIX}/" CACHE STRING "" FORCE)
-      endif()
-    endif()
-
     # Setting a variable to let sub-projects detect which other projects
     # will be included under here.
     set(HAVE_${canon_name} On)
@@ -153,15 +150,6 @@ if(${CMAKE_SOURCE_DIR} STREQUAL ${CMAKE_CURRENT_SOURCE_DIR})
   foreach(entry ${runtimes})
     get_filename_component(projName ${entry} NAME)
 
-    if(LLVM_RUNTIMES_TARGET)
-      if(NOT "${projName}" MATCHES "compiler-rt")
-        set(LLVM_BINARY_DIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_PREFIX}")
-        set(LLVM_LIBDIR_SUFFIX "${LLVM_RUNTIMES_LIBDIR_SUFFIX}")
-        set(LLVM_LIBRARY_OUTPUT_INTDIR "${LLVM_LIBRARY_DIR}/${LLVM_RUNTIMES_PREFIX}lib${LLVM_RUNTIMES_LIBDIR_SUFFIX}")
-        set(LLVM_RUNTIME_OUTPUT_INTDIR "${LLVM_TOOLS_BINARY_DIR}/${LLVM_RUNTIMES_PREFIX}")
-      endif()
-    endif()
-
     # Between each sub-project we want to cache and clear the LIT properties
     set_property(GLOBAL PROPERTY LLVM_LIT_TESTSUITES)
     set_property(GLOBAL PROPERTY LLVM_LIT_PARAMS)
@@ -247,6 +235,8 @@ else() # if this is included from LLVM's CMake
                              ${compiler_rt_path}/lib/builtins
                              CMAKE_ARGS -DLLVM_LIBRARY_OUTPUT_INTDIR=${LLVM_LIBRARY_DIR}
                                         -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_TOOLS_BINARY_DIR}
+                                        -DLLVM_DEFAULT_TARGET_TRIPLE=${TARGET_TRIPLE}
+                                        -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON
                                         -DCMAKE_C_COMPILER_TARGET=${TARGET_TRIPLE}
                                         -DCMAKE_ASM_COMPILER_TARGET=${TARGET_TRIPLE}
                                         -DCMAKE_C_COMPILER_WORKS=ON
@@ -278,6 +268,8 @@ else() # if this is included from LLVM's CMake
                              ${compiler_rt_path}/lib/builtins
                              CMAKE_ARGS -DLLVM_LIBRARY_OUTPUT_INTDIR=${LLVM_LIBRARY_DIR}
                                         -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_TOOLS_BINARY_DIR}
+                                        -DLLVM_DEFAULT_TARGET_TRIPLE=${target}
+                                        -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON
                                         -DCMAKE_C_COMPILER_TARGET=${target}
                                         -DCMAKE_ASM_COMPILER_TARGET=${target}
                                         -DCMAKE_C_COMPILER_WORKS=ON
@@ -371,6 +363,8 @@ else() # if this is included from LLVM's CMake
                              CMAKE_ARGS -DCOMPILER_RT_BUILD_BUILTINS=Off
                                         -DLLVM_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                                         -DLLVM_LIBRARY_DIR=${LLVM_LIBRARY_DIR}
+                                        -DLLVM_DEFAULT_TARGET_TRIPLE=${TARGET_TRIPLE}
+                                        -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON
                                         -DCMAKE_C_COMPILER_TARGET=${TARGET_TRIPLE}
                                         -DCMAKE_CXX_COMPILER_TARGET=${TARGET_TRIPLE}
                                         -DCMAKE_ASM_COMPILER_TARGET=${TARGET_TRIPLE}
@@ -455,6 +449,8 @@ else() # if this is included from LLVM's CMake
                              CMAKE_ARGS -DCOMPILER_RT_BUILD_BUILTINS=Off
                                         -DLLVM_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                                         -DLLVM_LIBRARY_DIR=${LLVM_LIBRARY_DIR}
+                                        -DLLVM_DEFAULT_TARGET_TRIPLE=${target}
+                                        -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON
                                         -DCMAKE_C_COMPILER_TARGET=${target}
                                         -DCMAKE_CXX_COMPILER_TARGET=${target}
                                         -DCMAKE_ASM_COMPILER_TARGET=${target}