1 /*

     2  * Copyright (c) 2016, Oracle and/or its affiliates. All rights reserved.

     3  * Copyright (c) 2016 SAP SE. All rights reserved.

     4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

     5  *

     6  * This code is free software; you can redistribute it and/or modify it

     7  * under the terms of the GNU General Public License version 2 only, as

     8  * published by the Free Software Foundation.

     9  *

    10  * This code is distributed in the hope that it will be useful, but WITHOUT

    11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

    12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

    13  * version 2 for more details (a copy is included in the LICENSE file that

    14  * accompanied this code).

    15  *

    16  * You should have received a copy of the GNU General Public License version

    17  * 2 along with this work; if not, write to the Free Software Foundation,

    18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

    19  *

    20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

    21  * or visit www.oracle.com if you need additional information or have any

    22  * questions.

    23  *

    24  */

    25 

    26 #include "precompiled.hpp"

    27 #include "asm/macroAssembler.inline.hpp"

    28 #include "code/vtableStubs.hpp"

    29 #include "interp_masm_s390.hpp"

    30 #include "memory/resourceArea.hpp"

    31 #include "oops/instanceKlass.hpp"

    32 #include "oops/klassVtable.hpp"

    33 #include "runtime/sharedRuntime.hpp"

    34 #include "vmreg_s390.inline.hpp"

    35 #ifdef COMPILER2

    36 #include "opto/runtime.hpp"

    37 #endif

    38 

    39 // Machine-dependent part of VtableStubs: create vtableStub of correct

    40 // size and initialize its code.

    41 

    42 #define __ masm->

    43 

    44 #ifndef PRODUCT

    45 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);

    46 #endif

    47 

    48 // Used by compiler only; may use only caller saved, non-argument registers.

    49 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {

    50 

    51   const int   code_length = VtableStub::pd_code_size_limit(true);

    52   VtableStub *s = new(code_length) VtableStub(true, vtable_index);

    53   if (s == NULL) { // Indicates OOM In the code cache.

    54     return NULL;

    55   }

    56 

    57   ResourceMark    rm;

    58   CodeBuffer      cb(s->entry_point(), code_length);

    59   MacroAssembler *masm = new MacroAssembler(&cb);

    60   address start_pc;

    61   int     padding_bytes = 0;

    62 

    63 #if (!defined(PRODUCT) && defined(COMPILER2))

    64   if (CountCompiledCalls) {

    65     // Count unused bytes

    66     //                  worst case             actual size

    67     padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true);

    68 

    69     // Use generic emitter for direct memory increment.

    70     // Abuse Z_method as scratch register for generic emitter.

    71     // It is loaded further down anyway before it is first used.

    72     __ add2mem_32(Address(Z_R1_scratch), 1, Z_method);

    73   }

    74 #endif

    75 

    76   assert(VtableStub::receiver_location() == Z_R2->as_VMReg(), "receiver expected in Z_ARG1");

    77 

    78   // Get receiver klass.

    79   // Must do an explicit check if implicit checks are disabled.

    80   address npe_addr = __ pc(); // npe == NULL ptr exception

    81   __ null_check(Z_ARG1, Z_R1_scratch, oopDesc::klass_offset_in_bytes());

    82   const Register rcvr_klass = Z_R1_scratch;

    83   __ load_klass(rcvr_klass, Z_ARG1);

    84 

    85   // Set method (in case of interpreted method), and destination address.

    86   int entry_offset = in_bytes(Klass::vtable_start_offset()) +

    87                      vtable_index * vtableEntry::size_in_bytes();

    88 

    89 #ifndef PRODUCT

    90   if (DebugVtables) {

    91     Label L;

    92     // Check offset vs vtable length.

    93     const Register vtable_idx = Z_R0_scratch;

    94 

    95     // Count unused bytes.

    96     //                  worst case             actual size

    97     padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(vtable_idx, vtable_index*vtableEntry::size_in_bytes(), true);

    98 

    99     assert(Immediate::is_uimm12(in_bytes(Klass::vtable_length_offset())), "disp to large");

   100     __ z_cl(vtable_idx, in_bytes(Klass::vtable_length_offset()), rcvr_klass);

   101     __ z_brl(L);

   102     __ z_lghi(Z_ARG3, vtable_index);  // Debug code, don't optimize.

   103     __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), Z_ARG1, Z_ARG3, false);

   104     // Count unused bytes (assume worst case here).

   105     padding_bytes += 12;

   106     __ bind(L);

   107   }

   108 #endif

   109 

   110   int v_off = entry_offset + vtableEntry::method_offset_in_bytes();

   111 

   112   // Duplicate safety code from enc_class Java_Dynamic_Call_dynTOC.

   113   if (Displacement::is_validDisp(v_off)) {

   114     __ z_lg(Z_method/*method oop*/, v_off, rcvr_klass/*class oop*/);

   115     // Account for the load_const in the else path.

   116     padding_bytes += __ load_const_size();

   117   } else {

   118     // Worse case, offset does not fit in displacement field.

   119     __ load_const(Z_method, v_off); // Z_method temporarily holds the offset value.

   120     __ z_lg(Z_method/*method oop*/, 0, Z_method/*method offset*/, rcvr_klass/*class oop*/);

   121   }

   122 

   123 #ifndef PRODUCT

   124   if (DebugVtables) {

   125     Label L;

   126     __ z_ltgr(Z_method, Z_method);

   127     __ z_brne(L);

   128     __ stop("Vtable entry is ZERO",102);

   129     __ bind(L);

   130   }

   131 #endif

   132 

   133   address ame_addr = __ pc(); // ame = abstract method error

   134 

   135   // Must do an explicit check if implicit checks are disabled.

   136   __ null_check(Z_method, Z_R1_scratch, in_bytes(Method::from_compiled_offset()));

   137   __ z_lg(Z_R1_scratch, in_bytes(Method::from_compiled_offset()), Z_method);

   138   __ z_br(Z_R1_scratch);

   139 

   140   masm->flush();

   141 

   142   s->set_exception_points(npe_addr, ame_addr);

   143 

   144   return s;

   145 }

   146 

   147 VtableStub* VtableStubs::create_itable_stub(int vtable_index) {

   148   const int   code_length = VtableStub::pd_code_size_limit(false);

   149   VtableStub *s = new(code_length) VtableStub(false, vtable_index);

   150   if (s == NULL) { // Indicates OOM in the code cache.

   151     return NULL;

   152   }

   153 

   154   ResourceMark    rm;

   155   CodeBuffer      cb(s->entry_point(), code_length);

   156   MacroAssembler *masm = new MacroAssembler(&cb);

   157   address start_pc;

   158   int     padding_bytes = 0;

   159 

   160 #if (!defined(PRODUCT) && defined(COMPILER2))

   161   if (CountCompiledCalls) {

   162     // Count unused bytes

   163     //                  worst case             actual size

   164     padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::nof_megamorphic_calls_addr(), true);

   165 

   166     // Use generic emitter for direct memory increment.

   167     // Use Z_tmp_1 as scratch register for generic emitter.

   168     __ add2mem_32((Z_R1_scratch), 1, Z_tmp_1);

   169   }

   170 #endif

   171 

   172   assert(VtableStub::receiver_location() == Z_R2->as_VMReg(), "receiver expected in Z_ARG1");

   173 

   174   // Entry arguments:

   175   //  Z_method: Interface

   176   //  Z_ARG1:   Receiver

   177   const Register rcvr_klass = Z_tmp_1;    // Used to compute itable_entry_addr.

   178                                           // Use extra reg to avoid re-load.

   179   const Register vtable_len = Z_tmp_2;    // Used to compute itable_entry_addr.

   180   const Register itable_entry_addr = Z_R1_scratch;

   181   const Register itable_interface  = Z_R0_scratch;

   182 

   183   // Get receiver klass.

   184   // Must do an explicit check if implicit checks are disabled.

   185   address npe_addr = __ pc(); // npe == NULL ptr exception

   186   __ null_check(Z_ARG1, Z_R1_scratch, oopDesc::klass_offset_in_bytes());

   187   __ load_klass(rcvr_klass, Z_ARG1);

   188 

   189   // Load start of itable entries into itable_entry.

   190   __ z_llgf(vtable_len, Address(rcvr_klass, Klass::vtable_length_offset()));

   191   __ z_sllg(vtable_len, vtable_len, exact_log2(vtableEntry::size_in_bytes()));

   192 

   193   // Loop over all itable entries until desired interfaceOop(Rinterface) found.

   194   const int vtable_base_offset = in_bytes(Klass::vtable_start_offset());

   195   // Count unused bytes.

   196   start_pc = __ pc();

   197   __ add2reg_with_index(itable_entry_addr, vtable_base_offset + itableOffsetEntry::interface_offset_in_bytes(), rcvr_klass, vtable_len);

   198   padding_bytes += 20 - (__ pc() - start_pc);

   199 

   200   const int itable_offset_search_inc = itableOffsetEntry::size() * wordSize;

   201   Label search;

   202   __ bind(search);

   203 

   204   // Handle IncompatibleClassChangeError in itable stubs.

   205   // If the entry is NULL then we've reached the end of the table

   206   // without finding the expected interface, so throw an exception.

   207   NearLabel   throw_icce;

   208   __ load_and_test_long(itable_interface, Address(itable_entry_addr));

   209   __ z_bre(throw_icce); // Throw the exception out-of-line.

   210   // Count unused bytes.

   211   start_pc = __ pc();

   212   __ add2reg(itable_entry_addr, itable_offset_search_inc);

   213   padding_bytes += 20 - (__ pc() - start_pc);

   214   __ z_cgr(itable_interface, Z_method);

   215   __ z_brne(search);

   216 

   217   // Entry found. Itable_entry_addr points to the subsequent entry (itable_offset_search_inc too far).

   218   // Get offset of vtable for interface.

   219 

   220   const Register vtable_offset = Z_R1_scratch;

   221   const Register itable_method = rcvr_klass;   // Calculated before.

   222 

   223   const int vtable_offset_offset = (itableOffsetEntry::offset_offset_in_bytes() -

   224                                     itableOffsetEntry::interface_offset_in_bytes()) -

   225                                    itable_offset_search_inc;

   226   __ z_llgf(vtable_offset, vtable_offset_offset, itable_entry_addr);

   227 

   228   // Compute itableMethodEntry and get method and entry point for compiler.

   229   const int method_offset = (itableMethodEntry::size() * wordSize * vtable_index) +

   230                             itableMethodEntry::method_offset_in_bytes();

   231 

   232   __ z_lg(Z_method, method_offset, vtable_offset, itable_method);

   233 

   234 #ifndef PRODUCT

   235   if (DebugVtables) {

   236     Label ok1;

   237     __ z_ltgr(Z_method, Z_method);

   238     __ z_brne(ok1);

   239     __ stop("method is null",103);

   240     __ bind(ok1);

   241   }

   242 #endif

   243 

   244   address ame_addr = __ pc();

   245   // Must do an explicit check if implicit checks are disabled.

   246   if (!ImplicitNullChecks) {

   247     __ compare64_and_branch(Z_method, (intptr_t) 0, Assembler::bcondEqual, throw_icce);

   248   }

   249   __ z_lg(Z_R1_scratch, in_bytes(Method::from_compiled_offset()), Z_method);

   250   __ z_br(Z_R1_scratch);

   251 

   252   // Handle IncompatibleClassChangeError in itable stubs.

   253   __ bind(throw_icce);

   254   // Count unused bytes

   255   //                  worst case          actual size

   256   // We force resolving of the call site by jumping to

   257   // the "handle wrong method" stub, and so let the

   258   // interpreter runtime do all the dirty work.

   259   padding_bytes += __ load_const_size() - __ load_const_optimized_rtn_len(Z_R1_scratch, (long)SharedRuntime::get_handle_wrong_method_stub(), true);

   260   __ z_br(Z_R1_scratch);

   261 

   262   masm->flush();

   263 

   264   s->set_exception_points(npe_addr, ame_addr);

   265   return s;

   266 }

   267 

   268 // In order to tune these parameters, run the JVM with VM options

   269 // +PrintMiscellaneous and +WizardMode to see information about

   270 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.

   271 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {

   272   int size = DebugVtables ? 216 : 0;

   273   if (CountCompiledCalls) {

   274     size += 6 * 4;

   275   }

   276   if (is_vtable_stub) {

   277     size += 52;

   278   } else {

   279     size += 104;

   280   }

   281   if (Universe::narrow_klass_base() != NULL) {

   282     size += 16; // A guess.

   283   }

   284   return size;

   285 }

   286 

   287 int VtableStub::pd_code_alignment() {

   288   const unsigned int icache_line_size = 32;

   289   return icache_line_size;

   290 }