[runtimes] Pass on RUNTIMES_<target>_... options when using runtime_default_target

[DavidSpickett]

Summary

When configuring with the following:
cmake -S "/home/david.spickett/llvm-project/llvm" -G Ninja -DCMAKE_BUILD_TYPE=Release \

-DLLVM_ENABLE_PROJECTS="clang" -DLLVM_ENABLE_RUNTIMES="compiler-rt;libunwind" \
-DLLVM_USE_LINKER=lld \
-DRUNTIMES_armv8l-unknown-linux-gnueabihf_COMPILER_RT_BUILD_GWP_ASAN=OFF

Prior to this patch BUILD_GWP_ASAN was not passed down to compiler-rt.

If you configured in a different way you would go through runtime_register_target
which does have logic to convert RUNTIMES_<target>_<setting> into just
<setting> to be passed to the sub project normally.

builtin_register_target also does this so I've lifted the code from that
into a function and use that in builtin_register_target and runtime_default_target.

runtime_register_target also handles "name" and "target" being different,
so I have left that as is.

Depends on D139536

[DavidSpickett]

See https://github.com/llvm/llvm-project/blob/ba57d2ad4e9ae39ab824430baece730649758dd5/clang/cmake/caches/Fuchsia-stage2.cmake#L114 for more examples of these RUNTIMES_ in use.

[DavidSpickett]

The specific use case here is to be able to work around the issue described in https://github.com/llvm/llvm-project/issues/60115. Seems logical that these RUNTIMES_ options would work for the default target too.

[DavidSpickett]

ping!

[DavidSpickett]

Rebase now the parent has landed.

[DavidSpickett]

ping!

Would like to get this onto 16 so that if we find more issues with the runtimes build on Arm, people have an option to work around them.

[DavidSpickett]

I think either I was not using the options correctly, or https://reviews.llvm.org/D141460 fixes this same thing in a different way.

llvm/runtimes/CMakeLists.txt

llvm_ExternalProject_Add(builtins
                            PASSTHROUGH_PREFIXES COMPILER_RT
                                                 DARWIN
                                                 SANITIZER
                            USE_TOOLCHAIN
                            TARGET_TRIPLE ${LLVM_TARGET_TRIPLE}
                            ${EXTRA_ARGS})
 endfunction()
 
-function(builtin_register_target compiler_rt_path target)
-  cmake_parse_arguments(ARG "" "" "DEPENDS" ${ARGN})
-
-  check_apple_target(${target} builtin)
-
+# Find variables with names of the form:
+# ${kind}_${target}_<runtimes cmake option>
+# Rename them so they can be passed directly to the runtime or builtins that
+# they apply to.
+#
+# For example:
+# RUNTIMES_armv8l-unknown-linux-gnueabihf_COMPILER_RT_BUILD_GWP_ASAN=OFF
+# Would be changed to:
+# COMPILER_RT_BUILD_GWP_ASAN=OFF
+# So it can be passed directly to compiler-rt.
+function (get_extra_cmake_args kind target)
   get_cmake_property(variableNames VARIABLES)
   foreach(variableName ${variableNames})
-    string(FIND "${variableName}" "BUILTINS_${target}" out)
+    string(FIND "${variableName}" "${kind}_${target}" out)
     if("${out}" EQUAL 0)
-      string(REPLACE "BUILTINS_${target}_" "" new_name ${variableName})
+      string(REPLACE "${kind}_${target}_" "" new_name ${variableName})
       string(REPLACE ";" "|" new_value "${${variableName}}")
       list(APPEND ${target}_extra_args "-D${new_name}=${new_value}")
     endif()
   endforeach()
+  set(${target}_extra_args ${${target}_extra_args} PARENT_SCOPE)
+endfunction()
+
+function(builtin_register_target compiler_rt_path target)
+  cmake_parse_arguments(ARG "" "" "DEPENDS" ${ARGN})
+
+  check_apple_target(${target} builtin)
+
+  get_extra_cmake_args("BUILTINS" ${target})
 
   llvm_ExternalProject_Add(builtins-${target}
                            ${compiler_rt_path}/lib/builtins
                            DEPENDS ${ARG_DEPENDS}
                            CMAKE_ARGS -DLLVM_LIBRARY_OUTPUT_INTDIR=${LLVM_LIBRARY_DIR}
                                       -DLLVM_RUNTIME_OUTPUT_INTDIR=${LLVM_TOOLS_BINARY_DIR}
                                       -DLLVM_DEFAULT_TARGET_TRIPLE=${target}
                                       -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=ON
foreach(entry ${runtimes})
   string(FIND ${projName} "lib" LIB_IDX)
   if(LIB_IDX EQUAL 0 AND NOT projName STREQUAL "libc")
     string(SUBSTRING ${projName} 3 -1 projName)
   endif()
   list(APPEND runtime_names ${projName})
 endforeach()
 
 function(runtime_default_target)
-  cmake_parse_arguments(ARG "" "" "DEPENDS;PREFIXES" ${ARGN})
+  cmake_parse_arguments(ARG "" "" "DEPENDS;PREFIXES;CMAKE_ARGS" ${ARGN})
 
   include(${LLVM_BINARY_DIR}/runtimes/Components.cmake OPTIONAL)
   set(SUB_CHECK_TARGETS ${SUB_CHECK_TARGETS} PARENT_SCOPE)
   set_property(DIRECTORY APPEND PROPERTY CMAKE_CONFIGURE_DEPENDS ${LLVM_BINARY_DIR}/runtimes/Components.cmake)
 
   foreach(runtime_name ${runtime_names})
     list(APPEND extra_targets
       ${runtime_name}
foreach(component ${LLVM_RUNTIME_DISTRIBUTION_COMPONENTS})
     endif()
   endforeach()
 
   if(LLVM_INCLUDE_TESTS)
     set_property(GLOBAL APPEND PROPERTY LLVM_ALL_LIT_TESTSUITES "@${LLVM_BINARY_DIR}/runtimes/runtimes-bins/lit.tests")
     list(APPEND test_targets runtimes-test-depends check-runtimes)
   endif()
 
+  get_extra_cmake_args("RUNTIMES" ${LLVM_TARGET_TRIPLE})
+
   set_enable_per_target_runtime_dir()
 
   llvm_ExternalProject_Add(runtimes
                            ${CMAKE_CURRENT_SOURCE_DIR}/../../runtimes
                            DEPENDS ${ARG_DEPENDS}
                            # Builtins were built separately above
                            CMAKE_ARGS -DCOMPILER_RT_BUILD_BUILTINS=Off
                                       -DLLVM_INCLUDE_TESTS=${LLVM_INCLUDE_TESTS}
                                       -DLLVM_DEFAULT_TARGET_TRIPLE=${LLVM_TARGET_TRIPLE}
                                       -DLLVM_ENABLE_PROJECTS_USED=${LLVM_ENABLE_PROJECTS_USED}
                                       -DLLVM_ENABLE_PER_TARGET_RUNTIME_DIR=${LLVM_ENABLE_PER_TARGET_RUNTIME_DIR}
                                       -DLLVM_BUILD_TOOLS=${LLVM_BUILD_TOOLS}
                                       -DCMAKE_C_COMPILER_WORKS=ON
                                       -DCMAKE_CXX_COMPILER_WORKS=ON
                                       -DCMAKE_ASM_COMPILER_WORKS=ON
                                       ${COMMON_CMAKE_ARGS}
                                       ${RUNTIMES_CMAKE_ARGS}
+                                      ${${LLVM_TARGET_TRIPLE}_extra_args}
                            PASSTHROUGH_PREFIXES LLVM_ENABLE_RUNTIMES
                                                 LLVM_USE_LINKER
                                                 ${ARG_PREFIXES}
                            EXTRA_TARGETS ${extra_targets}
                                          ${test_targets}
                                          ${SUB_COMPONENTS}
                                          ${SUB_CHECK_TARGETS}
                                          ${SUB_INSTALL_TARGETS}