[test-suite][mips] Deduce using MIPS architecture automatically

[atanasyan]

Summary

Use check_symbol_exists() to check macros defined by compiler and deduce enabled MIPS features like mips16. If for example mips16 is enabled, define MIPS_IS_MIPS16_ENABLED flag. Then use this flags to include feature specific test cases or disable tests unsupported for the feature.

[dsanders]

Why not use 'MATCHES'?

if(NOT MIPSARCH MATCHES mips16)

and similar.

[atanasyan]

In D17139#352802, @dsanders wrote:

Why not use 'MATCHES'?

if(NOT MIPSARCH MATCHES mips16)

and similar.

Is it possible to set MIPSARCH to something like mips16xxx like mips32 and mups32r2? If not, you are right and using MATCHES is the best choice.

[dsanders]

My thinking was that they're both substring matches and the shorter version is a bit simpler. Having dug into it a bit more it looks like MIPSARCH has just been transcribed from the Makefile where it was an arbitrary string provided by one of our internal buildbots. 'mips16' is the only MIPS16-related value I can see.

In light of that, we probably shouldn't require the user to provide it and instead figure it out from the CFLAGS/CXXFLAGS by checking for __mips16 with check_symbol_exists(). Similarly for the other checks on MIPSARCH.

[atanasyan]

In D17139#353104, @dsanders wrote:

we probably shouldn't require the user to provide it and instead figure it out from the CFLAGS/CXXFLAGS by checking for __mips16 with check_symbol_exists(). Similarly for the other checks on MIPSARCH.

Good point. I will rewrite the patch accordingly.

[atanasyan]

Use check_symbol_exists to automatically deduce enabled MIPS features, set the corresponding 'flags' and check this flag in CMakeLists.txt files.

[dsanders]

LGTM

CMakeLists.txt

 cmake_minimum_required(VERSION 3.2)
 
+include(CheckSymbolExists)
+
 # The test-suite is designed to be built in release mode anyway and
 # falls over unless -DNDEBUG is set.
 if (NOT CMAKE_BUILD_TYPE AND NOT CMAKE_CONFIGURATION_TYPES)
   message(STATUS "No build type selected, defaulting to Release")
   set(CMAKE_BUILD_TYPE "Release")
 endif()
 
 project(test-suite C CXX)
if(NOT DEFINED ENDIAN)
   test_big_endian(IS_BIGENDIAN)
   if(IS_BIGENDIAN)
     set(ENDIAN "big")
   else()
     set(ENDIAN "little")
   endif()
 endif()
 
+if("${ARCH}" STREQUAL "Mips")
+  check_symbol_exists(__mips16 "" MIPS_IS_MIPS16_ENABLED)
+  check_symbol_exists(__mips64 "" MIPS_IS_MIPS64_ENABLED)
+endif()
+
 add_subdirectory(tools)
 # Shortcut for the path to the fpcmp executable
 set(FPCMP ${CMAKE_BINARY_DIR}/tools/fpcmp)
 
 # Now that the tools have been created, use tools/timeit to time all other compilations.
 set(CMAKE_C_COMPILE_OBJECT "${CMAKE_BINARY_DIR}/tools/timeit --summary <OBJECT>.time ${CMAKE_C_COMPILE_OBJECT}")
 set(CMAKE_CXX_COMPILE_OBJECT "${CMAKE_BINARY_DIR}/tools/timeit --summary <OBJECT>.time ${CMAKE_CXX_COMPILE_OBJECT}")
 
 add_subdirectory(SingleSource)
 add_subdirectory(MultiSource)
 add_subdirectory(External)
 
 # Produce lit.site.cfg
 configure_file("${PROJECT_SOURCE_DIR}/lit.site.cfg.in" "${CMAKE_BINARY_DIR}/lit.site.cfg")

MultiSource/UnitTests/C++11/CMakeLists.txt

 list(APPEND CPPFLAGS -std=c++11)
-string(FIND "${MIPSARCH}" "mips16" TMP1)
-if("" STREQUAL "${TMP1}")
+
+if(NOT MIPS_IS_MIPS16_ENABLED)
   llvm_add_subdirectories(frame_layout)
 endif()

MultiSource/UnitTests/Mips/CMakeLists.txt

-string(FIND "${MIPSARCH}" "mips16" TMP1)
-if("" STREQUAL "${TMP1}")
+if(MIPS_IS_MIPS16_ENABLED)
   llvm_add_subdirectories(Mips16)
 endif()

SingleSource/UnitTests/CMakeLists.txt

 if("" STREQUAL "${TMP1}")
   list(APPEND PROGRAMS_TO_SKIP ms_struct-bitfield-init-1 ms_struct-bitfield-init ms_struct-bitfield ms_struct_pack_layout-1 ms_struct_pack_layout ms_struct-bitfield-1)
 endif()
 if("${ARCH}" STREQUAL "AArch64")
   list(APPEND PROGRAMS_TO_SKIP blockstret)
 endif()
 if("${ARCH}" STREQUAL "Mips")
   llvm_add_subdirectories(Mips)
-  string(FIND "${MIPSARCH}" "mips64" TMP2)
-  if("" STREQUAL "${TMP2}")
+  # Only MIPS 64-bit supports 8 bytes atomic operations.
+  if(NOT MIPS_IS_MIPS64_ENABLED)
     list(APPEND PROGRAMS_TO_SKIP AtomicOps)
   endif()
 endif()
 if("${ARCH}" STREQUAL "XCore")
   list(APPEND PROGRAMS_TO_SKIP AtomicOps)
   list(APPEND PROGRAMS_TO_SKIP initp1)
   set(XCORE_TARGET_NEEDS_MEMORY 1)
 endif()
 list(APPEND LDFLAGS -lstdc++)
 llvm_singlesource()

SingleSource/UnitTests/Mips/CMakeLists.txt

-string(FIND "${MIPSARCH}" "mips16" TMP1)
-if(NOT "" STREQUAL "${TMP1}")
+if(MIPS_IS_MIPS16_ENABLED)
   llvm_add_subdirectories(Mips16)
 endif()