[GS/StackClash] Implement getMemScale for a few more opcodes.

Author: kbeyls

llvm/lib/Target/AArch64/AArch64InstrInfo.cpp

@@ -3956,6 +3956,7 @@ int AArch64InstrInfo::getMemScale(unsigned Opc) {
   case AArch64::LDRSBWui:
   case AArch64::LDRSBWpre:
   case AArch64::LDRSBWpost:
+  case AArch64::LDRSBXui:
   case AArch64::LDRSBXpre:
   case AArch64::LDRSBXpost:
   case AArch64::LDURSBWi:
@@ -3975,6 +3976,7 @@ int AArch64InstrInfo::getMemScale(unsigned Opc) {
   case AArch64::LDRSHWui:
   case AArch64::LDRSHWpre:
   case AArch64::LDRSHWpost:
+  case AArch64::LDRSHXui:
   case AArch64::LDRSHXpre:
   case AArch64::LDRSHXpost:
   case AArch64::LDURSHWi: