8331393: AArch64: u32 _partial_subtype_ctr loaded/stored as 64

Reviewed-by: aph, fyang

Author: robehn

src/hotspot/cpu/aarch64/macroAssembler_aarch64.cpp

@@ -1560,11 +1560,7 @@ void MacroAssembler::check_klass_subtype_slow_path(Register sub_klass,
   }
 
 #ifndef PRODUCT
-  mov(rscratch2, (address)&SharedRuntime::_partial_subtype_ctr);
-  Address pst_counter_addr(rscratch2);
-  ldr(rscratch1, pst_counter_addr);
-  add(rscratch1, rscratch1, 1);
-  str(rscratch1, pst_counter_addr);
+  incrementw(ExternalAddress((address)&SharedRuntime::_partial_subtype_ctr));
 #endif //PRODUCT
 
   // We will consult the secondary-super array.

src/hotspot/cpu/aarch64/stubGenerator_aarch64.cpp

@@ -86,10 +86,7 @@ class StubGenerator: public StubCodeGenerator {
 #define inc_counter_np(counter) ((void)0)
 #else
   void inc_counter_np_(uint& counter) {
-    __ lea(rscratch2, ExternalAddress((address)&counter));
-    __ ldrw(rscratch1, Address(rscratch2));
-    __ addw(rscratch1, rscratch1, 1);
-    __ strw(rscratch1, Address(rscratch2));
+    __ incrementw(ExternalAddress((address)&counter));
   }
 #define inc_counter_np(counter) \
   BLOCK_COMMENT("inc_counter " #counter); \