src/cpu/s390/vm/interp_masm_s390.cpp

rev 12860 : imported patch 8171392_constantpool_ro.v3.patch
rev 12861 : ppc64 addons for 8171392: make contant pool read-only

@@ -1,8 +1,8 @@
 /*
  * Copyright (c) 2016, 2017, Oracle and/or its affiliates. All rights reserved.
- * Copyright (c) 2016 SAP SE. All rights reserved.
+ * Copyright (c) 2016, 2017 SAP SE. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 only, as
  * published by the Free Software Foundation.

@@ -385,10 +385,20 @@
 #endif
   z_agr(result, index);    // Address of indexed array element.
   load_heap_oop(result, arrayOopDesc::base_offset_in_bytes(T_OBJECT), result);
 }
 
+// load cpool->resolved_klass_at(index)
+void InterpreterMacroAssembler::load_resolved_klass_at_offset(Register cpool, Register offset, Register iklass) {
+  // int value = *(Rcpool->int_at_addr(which));
+  // int resolved_klass_index = extract_low_short_from_int(value);
+  z_llgh(offset, Address(cpool, offset, sizeof(ConstantPool) + 2)); // offset = resolved_klass_index (s390 is big-endian)
+  z_sllg(offset, offset, LogBytesPerWord);                          // Convert 'index' to 'offset'
+  z_lg(iklass, Address(cpool, ConstantPool::resolved_klasses_offset_in_bytes())); // iklass = cpool->_resolved_klasses
+  z_lg(iklass, Address(iklass, offset, Array<Klass*>::base_offset_in_bytes()));
+}
+
 void InterpreterMacroAssembler::get_cache_entry_pointer_at_bcp(Register cache,
                                                                Register tmp,
                                                                int bcp_offset,
                                                                size_t index_size) {
   BLOCK_COMMENT("get_cache_entry_pointer_at_bcp {");