Add {lda,stl}x?r{,b,h} instructions to ARM64 assembler/disassembler

src/arm64/decoder-arm64-inl.h

Index: src/arm64/decoder-arm64-inl.h
diff --git a/src/arm64/decoder-arm64-inl.h b/src/arm64/decoder-arm64-inl.h
index e00105e7bc1b49165c3a5853520e86bd943255fd..2405f8783000751dbc5f030772d36ff7486bfe6f 100644
--- a/src/arm64/decoder-arm64-inl.h
+++ b/src/arm64/decoder-arm64-inl.h
@@ -217,8 +217,15 @@ void Decoder<V>::DecodeLoadStore(Instruction* instr) {
     if (instr->Bit(28) == 0) {
       if (instr->Bit(29) == 0) {
         if (instr->Bit(26) == 0) {
-          // TODO(all): VisitLoadStoreExclusive.
-          V::VisitUnimplemented(instr);
+          if (instr->Mask(0xA08000) == 0x800000 ||
+              instr->Mask(0xA00000) == 0xA00000) {
+            V::VisitUnallocated(instr);
+          } else if (instr->Mask(0x808000) == 0) {
+            // Load/Store exclusive without acquire/release are unimplemented.
+            V::VisitUnimplemented(instr);
+          } else {
+            V::VisitLoadStoreAcquireRelease(instr);
+          }
         } else {
           DecodeAdvSIMDLoadStore(instr);
         }