Remove `COMPILER_RT_INSTALL_PATH`

[Ericson2314]

Summary

This patch removes those in order to simplify things for D99484.

It turns out we don't neeed to remove clang/runtime to make this work,
as @phosek thought might be necessary.

To do this, we just set CMAKE_INSTALL_PREFIX rather than
COMPILER_RT_INSTALL_PATH in clang/runtime in the child CMake
invocation. Since it's a separate CMake invocation, we don't have to
worry about mutation "bleeding over" and effecting other projects.

However I am still worrie about redefining of CMAKE_INSTALL_PREIX in
compiler-rt/cmake/base-config-ix.cmake. This occurs under
LLVM_TREE_AVAILABLE. If this is just for separate compiler-rt builds
(separate invocation of CMake, that is), this is fine. But if on the
other hand this is for combination builds in a single CMake run, then
this sort of redefinition is no good as it will effect more than
compiler-rt.

[phosek]

I'm worried that overriding CMAKE_INSTALL_PREFIX is going to break the runtimes build where we build compiler-rt, libcxx, libcxxabi, libunwind in a single CMake build, and compiler-rt always comes first see https://github.com/llvm/llvm-project/blob/98742e42fc50f58d3f2d3f2cdbbf540288c134b9/runtimes/CMakeLists.txt#L57.

[Ericson2314]

In D99860#2670359, @phosek wrote:

I'm worried that overriding CMAKE_INSTALL_PREFIX is going to break the runtimes build where we build compiler-rt, libcxx, libcxxabi, libunwind in a single CMake build, and compiler-rt always comes first see https://github.com/llvm/llvm-project/blob/98742e42fc50f58d3f2d3f2cdbbf540288c134b9/runtimes/CMakeLists.txt#L57.

Gotcha, and if (LLVM_TREE_AVAILABLE) would be true in that case? That means compiler-rt-specific variables are here to stay, but I no longer think that's so bad. See the latest https://reviews.llvm.org/D99484 for how polly works now, I can do that here.

[Ericson2314]

D101497 is more safe/conservative and gets the job done to prepare for`GnuInstallDirs`. Closing in favor of that.

clang/runtime/CMakeLists.txt

CMAKE_ARGS ${CLANG_COMPILER_RT_CMAKE_ARGS}
                -DCMAKE_CXX_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++
                -DCMAKE_ASM_COMPILER=${LLVM_RUNTIME_OUTPUT_INTDIR}/clang
                -DCMAKE_BUILD_TYPE=${CMAKE_BUILD_TYPE}
                -DCMAKE_MAKE_PROGRAM=${CMAKE_MAKE_PROGRAM}
                -DLLVM_CONFIG_PATH=${LLVM_RUNTIME_OUTPUT_INTDIR}/llvm-config
                -DLLVM_LIT_ARGS=${LLVM_LIT_ARGS}
                -DCOMPILER_RT_OUTPUT_DIR=${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION}
                -DCOMPILER_RT_EXEC_OUTPUT_DIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
-               -DCOMPILER_RT_INSTALL_PATH:STRING=lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}
+               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}/lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION}
                -DCOMPILER_RT_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
-               -DCMAKE_INSTALL_PREFIX=${CMAKE_INSTALL_PREFIX}
                -DLLVM_LIBDIR_SUFFIX=${LLVM_LIBDIR_SUFFIX}
                -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_RUNTIME_OUTPUT_INTDIR}
                -DCMAKE_OSX_DEPLOYMENT_TARGET=${CMAKE_OSX_DEPLOYMENT_TARGET}
                -DCMAKE_OSX_SYSROOT:PATH=${CMAKE_OSX_SYSROOT}
                ${COMPILER_RT_PASSTHROUGH_VARIABLES}
     INSTALL_COMMAND ""
     STEP_TARGETS configure build
     USES_TERMINAL_CONFIGURE 1

compiler-rt/cmake/Modules/AddCompilerRT.cmake

macro(add_compiler_rt_resource_file target_name file_name component)
   set(dst_file "${COMPILER_RT_OUTPUT_DIR}/share/${file_name}")
   add_custom_command(OUTPUT ${dst_file}
     DEPENDS ${src_file}
     COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src_file} ${dst_file}
     COMMENT "Copying ${file_name}...")
   add_custom_target(${target_name} DEPENDS ${dst_file})
   # Install in Clang resource directory.
   install(FILES ${file_name}
-    DESTINATION ${COMPILER_RT_INSTALL_PATH}/share
+    DESTINATION share
     COMPONENT ${component})
   add_dependencies(${component} ${target_name})
 
   set_target_properties(${target_name} PROPERTIES FOLDER "Compiler-RT Misc")
 endmacro()
 
 macro(add_compiler_rt_script name)
   set(dst ${COMPILER_RT_EXEC_OUTPUT_DIR}/${name})
   set(src ${CMAKE_CURRENT_SOURCE_DIR}/${name})
   add_custom_command(OUTPUT ${dst}
     DEPENDS ${src}
     COMMAND ${CMAKE_COMMAND} -E copy_if_different ${src} ${dst}
     COMMENT "Copying ${name}...")
   add_custom_target(${name} DEPENDS ${dst})
   install(FILES ${dst}
     PERMISSIONS OWNER_READ OWNER_WRITE OWNER_EXECUTE GROUP_READ GROUP_EXECUTE WORLD_READ WORLD_EXECUTE
-    DESTINATION ${COMPILER_RT_INSTALL_PATH}/bin)
+    DESTINATION bin)
 endmacro(add_compiler_rt_script src name)
 
 # Builds custom version of libc++ and installs it in <prefix>.
 # Can be used to build sanitized versions of libc++ for running unit tests.
 # add_custom_libcxx(<name> <prefix>
 #                   DEPS <list of build deps>
 #                   CFLAGS <list of compile flags>
 #                   USE_TOOLCHAIN)

compiler-rt/cmake/Modules/CompilerRTDarwinUtils.cmake

if(COMPILER_RT_SUPPORTED_ARCH MATCHES ".*armv.*")
     set(PIC_FLAG -fPIC)
     set(STATIC_FLAG -static)
 
     set(DARWIN_macho_embedded_ARCHS armv6m armv7m armv7em armv7 i386 x86_64)
 
     set(DARWIN_macho_embedded_LIBRARY_OUTPUT_DIR
       ${COMPILER_RT_OUTPUT_DIR}/lib/macho_embedded)
     set(DARWIN_macho_embedded_LIBRARY_INSTALL_DIR
-      ${COMPILER_RT_INSTALL_PATH}/lib/macho_embedded)
+      lib/macho_embedded)
       
     set(CFLAGS_armv7 "-target thumbv7-apple-darwin-eabi")
     set(CFLAGS_i386 "-march=pentium")
 
     darwin_read_list_from_file(common_FUNCTIONS ${MACHO_SYM_DIR}/common.txt)
     darwin_read_list_from_file(thumb2_FUNCTIONS ${MACHO_SYM_DIR}/thumb2.txt)
     darwin_read_list_from_file(thumb2_64_FUNCTIONS ${MACHO_SYM_DIR}/thumb2-64.txt)
     darwin_read_list_from_file(arm_FUNCTIONS ${MACHO_SYM_DIR}/arm.txt)

compiler-rt/cmake/Modules/CompilerRTUtils.cmake

else()
     set(target "${arch}${triple_suffix}")
   endif()
   set(${variable} ${target} PARENT_SCOPE)
 endfunction()
 
 function(get_compiler_rt_install_dir arch install_dir)
   if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
     get_compiler_rt_target(${arch} target)
-    set(${install_dir} ${COMPILER_RT_INSTALL_PATH}/lib/${target} PARENT_SCOPE)
+    set(${install_dir} lib/${target} PARENT_SCOPE)
   else()
     set(${install_dir} ${COMPILER_RT_LIBRARY_INSTALL_DIR} PARENT_SCOPE)
   endif()
 endfunction()
 
 function(get_compiler_rt_output_dir arch output_dir)
   if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
     get_compiler_rt_target(${arch} target)

compiler-rt/cmake/base-config-ix.cmake

if (LLVM_TREE_AVAILABLE)
   # Compute the Clang version from the LLVM version.
   # FIXME: We should be able to reuse CLANG_VERSION variable calculated
   #        in Clang cmake files, instead of copying the rules here.
   string(REGEX MATCH "[0-9]+\\.[0-9]+(\\.[0-9]+)?" CLANG_VERSION
          ${PACKAGE_VERSION})
   # Setup the paths where compiler-rt runtimes and headers should be stored.
   set(COMPILER_RT_OUTPUT_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR}/clang/${CLANG_VERSION})
   set(COMPILER_RT_EXEC_OUTPUT_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
-  set(COMPILER_RT_INSTALL_PATH lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION})
+  set(CMAKE_INSTALL_PREFIX ${CMAKE_INSTALL_PREFIX}lib${LLVM_LIBDIR_SUFFIX}/clang/${CLANG_VERSION})
   option(COMPILER_RT_INCLUDE_TESTS "Generate and build compiler-rt unit tests."
          ${LLVM_INCLUDE_TESTS})
   option(COMPILER_RT_ENABLE_WERROR "Fail and stop if warning is triggered"
          ${LLVM_ENABLE_WERROR})
 
   # Use just-built Clang to compile/link tests on all platforms.
   if (CMAKE_CROSSCOMPILING)
     if (CMAKE_HOST_WIN32)
if (LLVM_TREE_AVAILABLE)
   set(COMPILER_RT_TEST_CXX_COMPILER
     ${LLVM_RUNTIME_OUTPUT_INTDIR}/clang++${_host_executable_suffix})
 else()
     # Take output dir and install path from the user.
   set(COMPILER_RT_OUTPUT_DIR ${CMAKE_CURRENT_BINARY_DIR} CACHE PATH
     "Path where built compiler-rt libraries should be stored.")
   set(COMPILER_RT_EXEC_OUTPUT_DIR ${CMAKE_CURRENT_BINARY_DIR}/bin CACHE PATH
     "Path where built compiler-rt executables should be stored.")
-  set(COMPILER_RT_INSTALL_PATH ${CMAKE_INSTALL_PREFIX} CACHE PATH
-    "Path where built compiler-rt libraries should be installed.")
   option(COMPILER_RT_INCLUDE_TESTS "Generate and build compiler-rt unit tests." OFF)
   option(COMPILER_RT_ENABLE_WERROR "Fail and stop if warning is triggered" OFF)
   # Use a host compiler to compile/link tests.
   set(COMPILER_RT_TEST_COMPILER ${CMAKE_C_COMPILER} CACHE PATH "Compiler to use for testing")
   set(COMPILER_RT_TEST_CXX_COMPILER ${CMAKE_CXX_COMPILER} CACHE PATH "C++ Compiler to use for testing")
 endif()
 
 if("${COMPILER_RT_TEST_COMPILER}" MATCHES "clang[+]*$")
   set(COMPILER_RT_TEST_COMPILER_ID Clang)
 elseif("${COMPILER_RT_TEST_COMPILER}" MATCHES "clang.*.exe$")
   set(COMPILER_RT_TEST_COMPILER_ID Clang)
 else()
   set(COMPILER_RT_TEST_COMPILER_ID GNU)
 endif()
 
 if(NOT DEFINED COMPILER_RT_OS_DIR)
   string(TOLOWER ${CMAKE_SYSTEM_NAME} COMPILER_RT_OS_DIR)
 endif()
 if(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR AND NOT APPLE)
   set(COMPILER_RT_LIBRARY_OUTPUT_DIR
     ${COMPILER_RT_OUTPUT_DIR})
   set(COMPILER_RT_LIBRARY_INSTALL_DIR
-    ${COMPILER_RT_INSTALL_PATH})
+    "")
 else(LLVM_ENABLE_PER_TARGET_RUNTIME_DIR)
   set(COMPILER_RT_LIBRARY_OUTPUT_DIR
     ${COMPILER_RT_OUTPUT_DIR}/lib/${COMPILER_RT_OS_DIR})
   set(COMPILER_RT_LIBRARY_INSTALL_DIR
-    ${COMPILER_RT_INSTALL_PATH}/lib/${COMPILER_RT_OS_DIR})
+    lib/${COMPILER_RT_OS_DIR})
 endif()
 
 if(APPLE)
   # On Darwin if /usr/include/c++ doesn't exist, the user probably has Xcode but
   # not the command line tools (or is using macOS 10.14 or newer). If this is
   # the case, we need to find the OS X sysroot to pass to clang.
   if(NOT EXISTS /usr/include/c++)
     execute_process(COMMAND xcrun -sdk macosx --show-sdk-path

compiler-rt/include/CMakeLists.txt

 add_custom_target(compiler-rt-headers ALL DEPENDS ${out_files})
 add_dependencies(compiler-rt compiler-rt-headers)
 set_target_properties(compiler-rt-headers PROPERTIES FOLDER "Compiler-RT Misc")
 
 # Install sanitizer headers.
 install(FILES ${SANITIZER_HEADERS}
   COMPONENT compiler-rt-headers
   PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
-  DESTINATION ${COMPILER_RT_INSTALL_PATH}/include/sanitizer)
+  DESTINATION include/sanitizer)
 # Install fuzzer headers.
 install(FILES ${FUZZER_HEADERS}
   COMPONENT compiler-rt-headers
   PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
-  DESTINATION ${COMPILER_RT_INSTALL_PATH}/include/fuzzer)
+  DESTINATION include/fuzzer)
 # Install xray headers.
 install(FILES ${XRAY_HEADERS}
   COMPONENT compiler-rt-headers
   PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
-  DESTINATION ${COMPILER_RT_INSTALL_PATH}/include/xray)
+  DESTINATION include/xray)
 # Install profile headers.
 install(FILES ${PROFILE_HEADERS}
   COMPONENT compiler-rt-headers
   PERMISSIONS OWNER_READ OWNER_WRITE GROUP_READ WORLD_READ
-  DESTINATION ${COMPILER_RT_INSTALL_PATH}/include/profile)
+  DESTINATION include/profile)
 
 if (NOT CMAKE_CONFIGURATION_TYPES) # don't add this for IDEs.
   add_custom_target(install-compiler-rt-headers
                     DEPENDS compiler-rt-headers
                     COMMAND "${CMAKE_COMMAND}"
                             -DCMAKE_INSTALL_COMPONENT="compiler-rt-headers"
                             -P "${CMAKE_BINARY_DIR}/cmake_install.cmake"
                     USES_TERMINAL)
   add_custom_target(install-compiler-rt-headers-stripped
                     DEPENDS compiler-rt-headers
                     COMMAND "${CMAKE_COMMAND}"
                             -DCMAKE_INSTALL_COMPONENT="compiler-rt-headers"
                             -DCMAKE_INSTALL_DO_STRIP=1
                             -P "${CMAKE_BINARY_DIR}/cmake_install.cmake"
                     USES_TERMINAL)
 endif()

compiler-rt/lib/dfsan/CMakeLists.txt

add_custom_command(OUTPUT ${dfsan_abilist_filename}
                     ${CMAKE_COMMAND} -E make_directory ${dfsan_abilist_dir}
                    COMMAND
                      cat ${CMAKE_CURRENT_SOURCE_DIR}/done_abilist.txt
                          ${CMAKE_CURRENT_SOURCE_DIR}/libc_ubuntu1404_abilist.txt
                          > ${dfsan_abilist_filename}
                    DEPENDS done_abilist.txt libc_ubuntu1404_abilist.txt)
 add_dependencies(dfsan dfsan_abilist)
 install(FILES ${dfsan_abilist_filename}
-        DESTINATION ${COMPILER_RT_INSTALL_PATH}/share)
+        DESTINATION share)