[compiler-rt] Fix an MSVC build issue. (PR #111557)

[Martin Storsjö via llvm-commits]

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@@ -599,27 +599,29 @@ else()
   set(COMPILER_RT_LINK_OR_COPY copy)
 endif()
 
-foreach(pat cas swp ldadd ldclr ldeor ldset)
-  foreach(size 1 2 4 8 16)
-    foreach(model 1 2 3 4 5)
-      if(pat STREQUAL "cas" OR NOT size STREQUAL "16")
-        set(source_asm "${CMAKE_CURRENT_SOURCE_DIR}/aarch64/lse.S")
-        set(helper_asm "${OA_HELPERS_DIR}/outline_atomic_${pat}${size}_${model}.S")
-        add_custom_command(
-          OUTPUT "${helper_asm}"
-          COMMAND ${CMAKE_COMMAND} -E ${COMPILER_RT_LINK_OR_COPY} "${source_asm}" "${helper_asm}"
-          DEPENDS "${source_asm}"
-        )
-        set_source_files_properties("${helper_asm}"
-          PROPERTIES
-          COMPILE_DEFINITIONS "L_${pat};SIZE=${size};MODEL=${model}"
-          INCLUDE_DIRECTORIES "${CMAKE_CURRENT_SOURCE_DIR}"
-        )
-        list(APPEND aarch64_SOURCES "${helper_asm}")
-      endif()
-    endforeach(model)
-  endforeach(size)
-endforeach(pat)
+if(COMPILER_RT_HAS_ASM_LSE)
----------------
mstorsjo wrote:

`if (NOT MSVC)` also covers builds in clang-cl mode (as the cmake `MSVC` flag primarily indicates the general command line style of the compiler - I think it also is set for the intel compiler for windows, that also uses a cl-style interface).

To properly single out MSVC as opposed to clang-cl, we'd need to check `CMAKE_C_COMPILER_ID`.

https://github.com/llvm/llvm-project/pull/111557