How to change the binary directory?

Hello,

I am building llvm 3.8.0 32-bit on a 64-bit OS and I would like to have 32-bit binaries in a specific folder: "/usr/bin32" instead of "/usr/bin".

I already tried two ways that do not work:
1) I replaced "set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin)" by "set(LLVM_RUNTIME_OUTPUT_INTDIR ${CMAKE_CURRENT_BINARY_DIR}/${CMAKE_CFG_INTDIR}/bin32)" in the CMakeLists.txt file
2) I used "-DLLVM_TOOLS_BINARY_DIR=/usr/bin32" option

Do you know how to achieve that please?

Thank you.
Best regards.