[CMake] Move the AIX archiver settings to a module

[phosek]

Summary

This allows their reuse across projects. The name of the module
is intentionally generic because we would like to move more platform
checks there.

[phosek]

I'm thinking about moving https://github.com/llvm/llvm-project/blob/cfe5d768be95ae0a62cf430e56e7762cebf81a65/llvm/cmake/modules/HandleLLVMOptions.cmake#L174 and https://github.com/llvm/llvm-project/blob/cfe5d768be95ae0a62cf430e56e7762cebf81a65/compiler-rt/cmake/Modules/UseLibtool.cmake into CheckPlatform.cmake since this is logic we want to reuse across projects. Let me know if you have a better suggestion for the name of this module.

[ldionne]

In D115276#3177373, @phosek wrote:

Let me know if you have a better suggestion for the name of this module.

SetArchiverForPlatform? Or something that conveys the fact that (1) this is basically about ar, and (2) it actually performs an action (it sets global variables).

[ldionne]

In D115276#3177795, @ldionne wrote:

In D115276#3177373, @phosek wrote:

Let me know if you have a better suggestion for the name of this module.

SetArchiverForPlatform? Or something that conveys the fact that (1) this is basically about ar, and (2) it actually performs an action (it sets global variables).

SetPlatformToolchainTools?

[kaz7]

+1 for SetPlatformToolchainTools. :-)

[kaz7]

Is it OK to accept this patch by me? Or should we wait for @ldionne? Just curious.

[ldionne]

In D115276#3191287, @kaz7 wrote:

Is it OK to accept this patch by me? Or should we wait for @ldionne? Just curious.

For the record, the review guidelines we have for libc++/libc++abi do not necessarily apply to compiler-rt, so there's no requirement that someone from the libc++ review group gives an approval for this to make progress.

[kaz7]

In D115276#3192146, @ldionne wrote:

In D115276#3191287, @kaz7 wrote:

Is it OK to accept this patch by me? Or should we wait for @ldionne? Just curious.

For the record, the review guidelines we have for libc++/libc++abi do not necessarily apply to compiler-rt, so there's no requirement that someone from the libc++ review group gives an approval for this to make progress.

Thank you for clarifying.

[phosek]

Renamed the module to SetPlatformToolchainTools.cmake as suggested.

[smeenai]

LGTM

cmake/Modules/SetPlatformToolchainTools.cmake

4

Super nit: using an unquoted ${} inside an if is a bad idea cos of https://cmake.org/cmake/help/latest/command/if.html#variable-expansion. Should be either if(CMAKE_SYSTEM_NAME or if("${CMAKE_SYSTEM_NAME}"

[smeenai]

cmake/Modules/SetPlatformToolchainTools.cmake

4

(I know it's just a copypasta of the existing code, but might as well fix it while we're here)

cmake/Modules/SetPlatformToolchainTools.cmake

+get_property(languages GLOBAL PROPERTY ENABLED_LANGUAGES)
+
+if(CMAKE_SYSTEM_NAME MATCHES "AIX")
+  foreach(lang IN LISTS languages)
+    set(CMAKE_${lang}_ARCHIVE_CREATE "<CMAKE_AR> -X32_64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
+    set(CMAKE_${lang}_ARCHIVE_APPEND "<CMAKE_AR> -X32_64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
+    set(CMAKE_${lang}_ARCHIVE_FINISH "<CMAKE_RANLIB> -X32_64 <TARGET>")
+  endforeach()
+endif()

compiler-rt/CMakeLists.txt

list(INSERT CMAKE_MODULE_PATH 0
   )
 
 if(CMAKE_CONFIGURATION_TYPES)
   set(CMAKE_CFG_RESOLVED_INTDIR "${CMAKE_CFG_INTDIR}/")
 else()
   set(CMAKE_CFG_RESOLVED_INTDIR "")
 endif()
 
+include(SetPlatformToolchainTools)
 include(base-config-ix)
 include(CompilerRTUtils)
 
 option(COMPILER_RT_BUILD_BUILTINS "Build builtins" ON)
 mark_as_advanced(COMPILER_RT_BUILD_BUILTINS)
 option(COMPILER_RT_BUILD_CRT "Build crtbegin.o/crtend.o" ON)
 mark_as_advanced(COMPILER_RT_BUILD_CRT)
 option(COMPILER_RT_CRT_USE_EH_FRAME_REGISTRY "Use eh_frame in crtbegin.o/crtend.o" ON)
if (CMAKE_LINKER MATCHES "link.exe$")
   # files, rather than skipping these files in the build system.
   # Ideally, we would pass this flag only for the libraries that need
   # it, but CMake doesn't seem to have a way to set linker flags for
   # individual static libraries, so we enable the suppression flag for
   # the whole compiler-rt project.
   set(CMAKE_STATIC_LINKER_FLAGS "${CMAKE_STATIC_LINKER_FLAGS} /IGNORE:4221")
 endif()
 
-if(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
-  set(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> -X32_64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
-  set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> -X32_64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
-  set(CMAKE_C_ARCHIVE_APPEND "<CMAKE_AR> -X32_64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
-  set(CMAKE_CXX_ARCHIVE_APPEND "<CMAKE_AR> -X32_64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
-  set(CMAKE_C_ARCHIVE_FINISH "<CMAKE_RANLIB> -X32_64 <TARGET>")
-  set(CMAKE_CXX_ARCHIVE_FINISH "<CMAKE_RANLIB> -X32_64 <TARGET>")
-endif()
-
 add_subdirectory(include)
 
 option(COMPILER_RT_USE_LIBCXX
   "Enable compiler-rt to use libc++ from the source tree" ON)
 if(COMPILER_RT_USE_LIBCXX)
   if(LLVM_ENABLE_PROJECTS_USED)
     # Don't use libcxx if LLVM_ENABLE_PROJECTS does not enable it.
     set(COMPILER_RT_LIBCXX_PATH ${LLVM_EXTERNAL_LIBCXX_SOURCE_DIR})

compiler-rt/lib/builtins/CMakeLists.txt

list(INSERT CMAKE_MODULE_PATH 0
     )
 
   include(base-config-ix)
   include(CompilerRTUtils)
 
   load_llvm_config()
   construct_compiler_rt_default_triple()
 
+  include(SetPlatformToolchainTools)
   if(APPLE)
     include(CompilerRTDarwinUtils)
   endif()
   if(APPLE)
     include(UseLibtool)
   endif()
   include(AddCompilerRT)
-
-  if(${CMAKE_SYSTEM_NAME} MATCHES "AIX")
-    set(CMAKE_C_ARCHIVE_CREATE "<CMAKE_AR> -X32_64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
-    set(CMAKE_CXX_ARCHIVE_CREATE "<CMAKE_AR> -X32_64 qc <TARGET> <LINK_FLAGS> <OBJECTS>")
-    set(CMAKE_C_ARCHIVE_APPEND "<CMAKE_AR> -X32_64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
-    set(CMAKE_CXX_ARCHIVE_APPEND "<CMAKE_AR> -X32_64 q <TARGET> <LINK_FLAGS> <OBJECTS>")
-    set(CMAKE_C_ARCHIVE_FINISH "<CMAKE_RANLIB> -X32_64 <TARGET>")
-    set(CMAKE_CXX_ARCHIVE_FINISH "<CMAKE_RANLIB> -X32_64 <TARGET>")
-  endif()
 endif()
 
 if (COMPILER_RT_STANDALONE_BUILD)
   # When compiler-rt is being built standalone, possibly as a cross-compilation
   # target, the target may or may not want position independent code. This
   # option provides an avenue through which the flag may be controlled when an
   # LLVM configuration is not being utilized.
   option(COMPILER_RT_BUILTINS_ENABLE_PIC