[AIX][compiler-rt][builtins] Don't add ppc builtin implementations that require __int128 on AIX

since __int128 currently isn't supported on AIX.

Reviewed By: hubert.reinterpretcast

Differential Revision: https://reviews.llvm.org/D85972

compiler-rt/lib/builtins/CMakeLists.txt

@@ -553,11 +553,8 @@ set(mips64el_SOURCES ${GENERIC_TF_SOURCES}
 
 set(powerpc64_SOURCES
   ppc/divtc3.c
-  ppc/fixtfti.c
   ppc/fixtfdi.c
-  ppc/fixunstfti.c
   ppc/fixunstfdi.c
-  ppc/floattitf.c
   ppc/floatditf.c
   ppc/floatunditf.c
   ppc/gcc_qadd.c
@@ -567,6 +564,15 @@ set(powerpc64_SOURCES
   ppc/multc3.c
   ${GENERIC_SOURCES}
 )
+# These routines require __int128, which isn't supported on AIX.
+if (NOT ${CMAKE_SYSTEM_NAME} MATCHES "AIX")
+  set(powerpc64_SOURCES
+    ppc/floattitf.c
+    ppc/fixtfti.c
+    ppc/fixunstfti.c
+    ${powerpc64_SOURCES}
+  )
+endif()
 set(powerpc64le_SOURCES ${powerpc64_SOURCES})
 
 set(riscv_SOURCES ${GENERIC_SOURCES} ${GENERIC_TF_SOURCES})