convert memmove to milicode call in 64-bit mode

Author: diggerlin

llvm/include/llvm/IR/RuntimeLibcalls.td

@@ -2333,7 +2333,7 @@ defset list<RuntimeLibcallImpl> PPCRuntimeLibcalls = {
 
 defset list<RuntimeLibcallImpl> PPC64AIXCallList = {
   def ___memcmp64 : RuntimeLibcallImpl<MEMCMP>;
-  def ___memmove64 : RuntimeLibcallImpl<MEMCPY>;
+  def ___memmove64 : RuntimeLibcallImpl<MEMMOVE>;
   def ___memset64 : RuntimeLibcallImpl<MEMSET>;
   def ___bzero64 : RuntimeLibcallImpl<BZERO>;
   def ___strlen64 : RuntimeLibcallImpl<STRLEN>;

llvm/test/CodeGen/PowerPC/milicode64.ll

@@ -156,7 +156,7 @@ define ptr @test_memmove(ptr noundef %destination, ptr noundef %source, i64 noun
 ; CHECK-AIX-64-P9-NEXT:    std r3, 128(r1)
 ; CHECK-AIX-64-P9-NEXT:    std r4, 120(r1)
 ; CHECK-AIX-64-P9-NEXT:    std r5, 112(r1)
-; CHECK-AIX-64-P9-NEXT:    bl .memmove[PR]
+; CHECK-AIX-64-P9-NEXT:    bl .___memmove64[PR]
 ; CHECK-AIX-64-P9-NEXT:    nop
 ; CHECK-AIX-64-P9-NEXT:    mr r3, r31
 ; CHECK-AIX-64-P9-NEXT:    ld r31, 136(r1) # 8-byte Folded Reload