jdk8-mips64-public/hotspot: src/cpu/x86/vm/vtableStubs_x86

src/cpu/x86/vm/vtableStubs_x86_32.cpp@bb1da64b0492 (annotated)

src/cpu/x86/vm/vtableStubs_x86_32.cpp

Fri, 16 Aug 2019 16:50:17 +0200

author: eosterlund
date: Fri, 16 Aug 2019 16:50:17 +0200
changeset 9834: bb1da64b0492
parent 9327: f96fcd9e1e1b
child 9448: 73d689add964
permissions: -rw-r--r--

8229345: Memory leak due to vtable stubs not being shared on SPARC
Reviewed-by: mdoerr, dholmes, kvn

 /*
  * Copyright (c) 1997, 2017, Oracle and/or its affiliates. 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.
  *
  * This code is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  * version 2 for more details (a copy is included in the LICENSE file that
  * accompanied this code).
  *
  * You should have received a copy of the GNU General Public License version
  * 2 along with this work; if not, write to the Free Software Foundation,
  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  *
  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  * or visit www.oracle.com if you need additional information or have any
  * questions.
  *
  */
 #include "precompiled.hpp"
 #include "asm/macroAssembler.hpp"
 #include "code/vtableStubs.hpp"
 #include "interp_masm_x86.hpp"
 #include "memory/resourceArea.hpp"
 #include "oops/compiledICHolder.hpp"
 #include "oops/instanceKlass.hpp"
 #include "oops/klassVtable.hpp"
 #include "runtime/sharedRuntime.hpp"
 #include "vmreg_x86.inline.hpp"
 #ifdef COMPILER2
 #include "opto/runtime.hpp"
 #endif
 // machine-dependent part of VtableStubs: create VtableStub of correct size and
 // initialize its code
 #define __ masm->
 #ifndef PRODUCT
 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);
 #endif
 // These stubs are used by the compiler only.
 // Argument registers, which must be preserved:
 //   rcx - receiver (always first argument)
 //   rdx - second argument (if any)
 // Other registers that might be usable:
 //   rax - inline cache register (is interface for itable stub)
 //   rbx - method (used when calling out to interpreter)
 // Available now, but may become callee-save at some point:
 //   rsi, rdi
 // Note that rax and rdx are also used for return values.
 //
 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
   const int i486_code_length = VtableStub::pd_code_size_limit(true);
   VtableStub* s = new(i486_code_length) VtableStub(true, vtable_index);
   // Can be NULL if there is no free space in the code cache.
   if (s == NULL) {
     return NULL;
   }
   ResourceMark rm;
   CodeBuffer cb(s->entry_point(), i486_code_length);
   MacroAssembler* masm = new MacroAssembler(&cb);
 #ifndef PRODUCT
   if (CountCompiledCalls) {
     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
   }
 #endif /* PRODUCT */
   // get receiver (need to skip return address on top of stack)
   assert(VtableStub::receiver_location() == rcx->as_VMReg(), "receiver expected in rcx");
   // get receiver klass
   address npe_addr = __ pc();
   __ movptr(rax, Address(rcx, oopDesc::klass_offset_in_bytes()));
 #ifndef PRODUCT
   if (DebugVtables) {
     Label L;
     // check offset vs vtable length
     __ cmpl(Address(rax, InstanceKlass::vtable_length_offset()*wordSize), vtable_index*vtableEntry::size());
     __ jcc(Assembler::greater, L);
     __ movl(rbx, vtable_index);
     __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), rcx, rbx);
     __ bind(L);
   }
 #endif // PRODUCT
   const Register method = rbx;
   // load Method* and target address
   __ lookup_virtual_method(rax, vtable_index, method);
   if (DebugVtables) {
     Label L;
     __ cmpptr(method, (int32_t)NULL_WORD);
     __ jcc(Assembler::equal, L);
     __ cmpptr(Address(method, Method::from_compiled_offset()), (int32_t)NULL_WORD);
     __ jcc(Assembler::notZero, L);
     __ stop("Vtable entry is NULL");
     __ bind(L);
   }
   // rax,: receiver klass
   // method (rbx): Method*
   // rcx: receiver
   address ame_addr = __ pc();
   __ jmp( Address(method, Method::from_compiled_offset()));
   masm->flush();
   if (PrintMiscellaneous && (WizardMode || Verbose)) {
     tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
                   vtable_index, p2i(s->entry_point()),
                   (int)(s->code_end() - s->entry_point()),
                   (int)(s->code_end() - __ pc()));
   }
   guarantee(__ pc() <= s->code_end(), "overflowed buffer");
   // shut the door on sizing bugs
   int slop = 3;  // 32-bit offset is this much larger than an 8-bit one
   assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
   s->set_exception_points(npe_addr, ame_addr);
   return s;
 }
 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
   // Note well: pd_code_size_limit is the absolute minimum we can get away with.  If you
   //            add code here, bump the code stub size returned by pd_code_size_limit!
   const int i486_code_length = VtableStub::pd_code_size_limit(false);
   VtableStub* s = new(i486_code_length) VtableStub(false, itable_index);
   // Can be NULL if there is no free space in the code cache.
   if (s == NULL) {
     return NULL;
   }
   ResourceMark rm;
   CodeBuffer cb(s->entry_point(), i486_code_length);
   MacroAssembler* masm = new MacroAssembler(&cb);
   // Entry arguments:
   //  rax: CompiledICHolder
   //  rcx: Receiver
 #ifndef PRODUCT
   if (CountCompiledCalls) {
     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
   }
 #endif /* PRODUCT */
   // Most registers are in use; we'll use rax, rbx, rsi, rdi
   // (If we need to make rsi, rdi callee-save, do a push/pop here.)
   const Register recv_klass_reg     = rsi;
   const Register holder_klass_reg   = rax; // declaring interface klass (DECC)
   const Register resolved_klass_reg = rbx; // resolved interface klass (REFC)
   const Register temp_reg           = rdi;
   const Register icholder_reg = rax;
   __ movptr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
   __ movptr(holder_klass_reg,   Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
   Label L_no_such_interface;
   // get receiver klass (also an implicit null-check)
   address npe_addr = __ pc();
   assert(VtableStub::receiver_location() ==  rcx->as_VMReg(), "receiver expected in  rcx");
   __ load_klass(recv_klass_reg, rcx);
   // Receiver subtype check against REFC.
   // Destroys recv_klass_reg value.
   __ lookup_interface_method(// inputs: rec. class, interface
                              recv_klass_reg, resolved_klass_reg, noreg,
                              // outputs:  scan temp. reg1, scan temp. reg2
                              recv_klass_reg, temp_reg,
                              L_no_such_interface,
                              /*return_method=*/false);
   // Get selected method from declaring class and itable index
   const Register method = rbx;
   __ load_klass(recv_klass_reg, rcx); // restore recv_klass_reg
   __ lookup_interface_method(// inputs: rec. class, interface, itable index
                              recv_klass_reg, holder_klass_reg, itable_index,
                              // outputs: method, scan temp. reg
                              method, temp_reg,
                              L_no_such_interface);
   // method (rbx): Method*
   // rcx: receiver
 #ifdef ASSERT
   if (DebugVtables) {
       Label L1;
       __ cmpptr(method, (int32_t)NULL_WORD);
       __ jcc(Assembler::equal, L1);
       __ cmpptr(Address(method, Method::from_compiled_offset()), (int32_t)NULL_WORD);
       __ jcc(Assembler::notZero, L1);
       __ stop("Method* is null");
       __ bind(L1);
     }
 #endif // ASSERT
   address ame_addr = __ pc();
   __ jmp(Address(method, Method::from_compiled_offset()));
   __ bind(L_no_such_interface);
   __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
   __ flush();
   if (PrintMiscellaneous && (WizardMode || Verbose)) {
     tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
                   itable_index, p2i(s->entry_point()),
                   (int)(s->code_end() - s->entry_point()),
                   (int)(s->code_end() - __ pc()));
   }
   guarantee(__ pc() <= s->code_end(), "overflowed buffer");
   // shut the door on sizing bugs
   int slop = 3;  // 32-bit offset is this much larger than an 8-bit one
   assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
   s->set_exception_points(npe_addr, ame_addr);
   return s;
 }
 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
   if (is_vtable_stub) {
     // Vtable stub size
     return (DebugVtables ? 210 : 16) + (CountCompiledCalls ? 6 : 0);
   } else {
     // Itable stub size
     return (DebugVtables ? 256 : 116) + (CountCompiledCalls ? 6 : 0);
   }
   // In order to tune these parameters, run the JVM with VM options
   // +PrintMiscellaneous and +WizardMode to see information about
   // actual itable stubs.  Look for lines like this:
   //   itable #1 at 0x5551212[65] left over: 3
   // Reduce the constants so that the "left over" number is >=3
   // for the common cases.
   // Do not aim at a left-over number of zero, because a
   // large vtable or itable index (> 16) will require a 32-bit
   // immediate displacement instead of an 8-bit one.
   //
   // The JVM98 app. _202_jess has a megamorphic interface call.
   // The itable code looks like this:
   // Decoding VtableStub itbl[1]@1
   //   mov    0x4(%ecx),%esi
   //   mov    0xe8(%esi),%edi
   //   lea    0x130(%esi,%edi,4),%edi
   //   add    $0x7,%edi
   //   and    $0xfffffff8,%edi
   //   lea    0x4(%esi),%esi
   //   mov    (%edi),%ebx
   //   cmp    %ebx,%eax
   //   je     success
   // loop:
   //   test   %ebx,%ebx
   //   je     throw_icce
   //   add    $0x8,%edi
   //   mov    (%edi),%ebx
   //   cmp    %ebx,%eax
   //   jne    loop
   // success:
   //   mov    0x4(%edi),%edi
   //   mov    (%esi,%edi,1),%ebx
   //   jmp    *0x44(%ebx)
   // throw_icce:
   //   jmp    throw_ICCE_entry
 }
 int VtableStub::pd_code_alignment() {
   return wordSize;
 }

Mercurial > jdk8-mips64-public > hotspot / annotate

src/cpu/x86/vm/vtableStubs_x86_32.cpp@bb1da64b0492 (annotated)

src/cpu/x86/vm/vtableStubs_x86_32.cpp