[JITLink][AARCH64][NFC] Create isLoadStoreImm12 function by splitting getPageOffset12Shift

[sunho]

Summary

Split getPageOffset12Shift function to get isLoadStoreImm12 util function which will be used for validating elf/aarch64 ldst relocation types.

[sunho]

Truncated diff

[sgraenitz]

LGTM!

[lhames]

LGTM.

llvm/include/llvm/ExecutionEngine/JITLink/aarch64.h

enum EdgeKind_aarch64 : Edge::Kind {
   NegDelta32,
   NegDelta64,
 };
 
 /// Returns a string name for the given aarch64 edge. For debugging purposes
 /// only
 const char *getEdgeKindName(Edge::Kind K);
 
-inline unsigned getPageOffset12Shift(uint32_t Instr) {
+inline bool isLoadStoreImm12(uint32_t Instr) {
   constexpr uint32_t LoadStoreImm12Mask = 0x3b000000;
+  return (Instr & LoadStoreImm12Mask) == 0x39000000;
+}
+
+inline unsigned getPageOffset12Shift(uint32_t Instr) {
   constexpr uint32_t Vec128Mask = 0x04800000;
 
-  if ((Instr & LoadStoreImm12Mask) == 0x39000000) {
+  if (isLoadStoreImm12(Instr)) {
     uint32_t ImplicitShift = Instr >> 30;
     if (ImplicitShift == 0)
       if ((Instr & Vec128Mask) == Vec128Mask)
         ImplicitShift = 4;
 
     return ImplicitShift;
   }