Fix CMake LLVM_TARGETS_TO_BUILD "Native" option to work with JIT

[mehdi_amini]

Summary

LLVM_TARGETS_TO_BUILD accepts both "host" or "Native" for auto-selecting
the target from the environment. However the way "Native" was plumbed
would lead to the JIT environment being disabled. This patch is making
"Native" works just as "host".

[rnk]

lgtm

We ought to disable these noisy openmp libarcher presubmit test failures that have been going on for the last several days.

llvm/CMakeLists.txt

 set(LLVM_PROFDATA_FILE "" CACHE FILEPATH
   "Profiling data file to use when compiling in order to improve runtime performance.")
 
 # All options referred to from HandleLLVMOptions have to be specified
 # BEFORE this include, otherwise options will not be correctly set on
 # first cmake run
 include(config-ix)
 
-string(REPLACE "Native" ${LLVM_NATIVE_ARCH}
-  LLVM_TARGETS_TO_BUILD "${LLVM_TARGETS_TO_BUILD}")
-list(REMOVE_DUPLICATES LLVM_TARGETS_TO_BUILD)
-
 # By default, we target the host, but this can be overridden at CMake
 # invocation time.
 set(LLVM_DEFAULT_TARGET_TRIPLE "${LLVM_HOST_TRIPLE}" CACHE STRING
   "Default target for which LLVM will generate code." )
 set(TARGET_TRIPLE "${LLVM_DEFAULT_TARGET_TRIPLE}")
 message(STATUS "LLVM host triple: ${LLVM_HOST_TRIPLE}")
 message(STATUS "LLVM default target triple: ${LLVM_DEFAULT_TARGET_TRIPLE}")
 

llvm/cmake/config-ix.cmake

 elseif (LLVM_NATIVE_ARCH MATCHES "riscv32")
   set(LLVM_NATIVE_ARCH RISCV)
 elseif (LLVM_NATIVE_ARCH MATCHES "riscv64")
   set(LLVM_NATIVE_ARCH RISCV)
 else ()
   message(FATAL_ERROR "Unknown architecture ${LLVM_NATIVE_ARCH}")
 endif ()
 
-# If build targets includes "host", then replace with native architecture.
-list(FIND LLVM_TARGETS_TO_BUILD "host" idx)
+# If build targets includes "host" or "Native", then replace with native architecture.
+foreach (NATIVE_KEYWORD host Native)
+  list(FIND LLVM_TARGETS_TO_BUILD ${NATIVE_KEYWORD} idx)
   if( NOT idx LESS 0 )
     list(REMOVE_AT LLVM_TARGETS_TO_BUILD ${idx})
     list(APPEND LLVM_TARGETS_TO_BUILD ${LLVM_NATIVE_ARCH})
     list(REMOVE_DUPLICATES LLVM_TARGETS_TO_BUILD)
   endif()
+endforeach()
 
 list(FIND LLVM_TARGETS_TO_BUILD ${LLVM_NATIVE_ARCH} NATIVE_ARCH_IDX)
 if (NATIVE_ARCH_IDX EQUAL -1)
   message(STATUS
     "Native target ${LLVM_NATIVE_ARCH} is not selected; lli will not JIT code")
 else ()
   message(STATUS "Native target architecture is ${LLVM_NATIVE_ARCH}")
   set(LLVM_NATIVE_TARGET LLVMInitialize${LLVM_NATIVE_ARCH}Target)