duke@435: /*
xdono@1279:  * Copyright 1997-2009 Sun Microsystems, Inc.  All Rights Reserved.
duke@435:  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
duke@435:  *
duke@435:  * This code is free software; you can redistribute it and/or modify it
duke@435:  * under the terms of the GNU General Public License version 2 only, as
duke@435:  * published by the Free Software Foundation.
duke@435:  *
duke@435:  * This code is distributed in the hope that it will be useful, but WITHOUT
duke@435:  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
duke@435:  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
duke@435:  * version 2 for more details (a copy is included in the LICENSE file that
duke@435:  * accompanied this code).
duke@435:  *
duke@435:  * You should have received a copy of the GNU General Public License version
duke@435:  * 2 along with this work; if not, write to the Free Software Foundation,
duke@435:  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
duke@435:  *
duke@435:  * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
duke@435:  * CA 95054 USA or visit www.sun.com if you need additional information or
duke@435:  * have any questions.
duke@435:  *
duke@435:  */
duke@435: 
duke@435: #include "incls/_precompiled.incl"
duke@435: #include "incls/_vtableStubs_x86_32.cpp.incl"
duke@435: 
duke@435: // machine-dependent part of VtableStubs: create VtableStub of correct size and
duke@435: // initialize its code
duke@435: 
duke@435: #define __ masm->
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: extern "C" void bad_compiled_vtable_index(JavaThread* thread, oop receiver, int index);
duke@435: #endif
duke@435: 
jrose@1058: // These stubs are used by the compiler only.
jrose@1058: // Argument registers, which must be preserved:
jrose@1058: //   rcx - receiver (always first argument)
jrose@1058: //   rdx - second argument (if any)
jrose@1058: // Other registers that might be usable:
jrose@1058: //   rax - inline cache register (is interface for itable stub)
jrose@1058: //   rbx - method (used when calling out to interpreter)
jrose@1058: // Available now, but may become callee-save at some point:
jrose@1058: //   rsi, rdi
jrose@1058: // Note that rax and rdx are also used for return values.
duke@435: //
duke@435: VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
duke@435:   const int i486_code_length = VtableStub::pd_code_size_limit(true);
duke@435:   VtableStub* s = new(i486_code_length) VtableStub(true, vtable_index);
duke@435:   ResourceMark rm;
duke@435:   CodeBuffer cb(s->entry_point(), i486_code_length);
duke@435:   MacroAssembler* masm = new MacroAssembler(&cb);
duke@435: 
duke@435: #ifndef PRODUCT
duke@435: 
duke@435:   if (CountCompiledCalls) {
never@739:     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
duke@435:   }
duke@435: #endif /* PRODUCT */
duke@435: 
duke@435:   // get receiver (need to skip return address on top of stack)
duke@435:   assert(VtableStub::receiver_location() == rcx->as_VMReg(), "receiver expected in rcx");
duke@435: 
duke@435:   // get receiver klass
duke@435:   address npe_addr = __ pc();
never@739:   __ movptr(rax, Address(rcx, oopDesc::klass_offset_in_bytes()));
duke@435:   // compute entry offset (in words)
duke@435:   int entry_offset = instanceKlass::vtable_start_offset() + vtable_index*vtableEntry::size();
duke@435: #ifndef PRODUCT
duke@435:   if (DebugVtables) {
duke@435:     Label L;
duke@435:     // check offset vs vtable length
duke@435:     __ cmpl(Address(rax, instanceKlass::vtable_length_offset()*wordSize), vtable_index*vtableEntry::size());
duke@435:     __ jcc(Assembler::greater, L);
duke@435:     __ movl(rbx, vtable_index);
duke@435:     __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), rcx, rbx);
duke@435:     __ bind(L);
duke@435:   }
duke@435: #endif // PRODUCT
duke@435: 
duke@435:   const Register method = rbx;
duke@435: 
duke@435:   // load methodOop and target address
never@739:   __ movptr(method, Address(rax, entry_offset*wordSize + vtableEntry::method_offset_in_bytes()));
duke@435:   if (DebugVtables) {
duke@435:     Label L;
never@739:     __ cmpptr(method, (int32_t)NULL_WORD);
duke@435:     __ jcc(Assembler::equal, L);
never@739:     __ cmpptr(Address(method, methodOopDesc::from_compiled_offset()), (int32_t)NULL_WORD);
duke@435:     __ jcc(Assembler::notZero, L);
duke@435:     __ stop("Vtable entry is NULL");
duke@435:     __ bind(L);
duke@435:   }
duke@435: 
duke@435:   // rax,: receiver klass
duke@435:   // method (rbx): methodOop
duke@435:   // rcx: receiver
duke@435:   address ame_addr = __ pc();
duke@435:   __ jmp( Address(method, methodOopDesc::from_compiled_offset()));
duke@435: 
duke@435:   masm->flush();
jrose@1058: 
jrose@1058:   if (PrintMiscellaneous && (WizardMode || Verbose)) {
jrose@1058:     tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",
jrose@1058:                   vtable_index, s->entry_point(),
jrose@1058:                   (int)(s->code_end() - s->entry_point()),
jrose@1058:                   (int)(s->code_end() - __ pc()));
jrose@1058:   }
jrose@1058:   guarantee(__ pc() <= s->code_end(), "overflowed buffer");
jrose@1144:   // shut the door on sizing bugs
jrose@1144:   int slop = 3;  // 32-bit offset is this much larger than an 8-bit one
jrose@1144:   assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
jrose@1058: 
duke@435:   s->set_exception_points(npe_addr, ame_addr);
duke@435:   return s;
duke@435: }
duke@435: 
duke@435: 
jrose@1058: VtableStub* VtableStubs::create_itable_stub(int itable_index) {
duke@435:   // Note well: pd_code_size_limit is the absolute minimum we can get away with.  If you
duke@435:   //            add code here, bump the code stub size returned by pd_code_size_limit!
duke@435:   const int i486_code_length = VtableStub::pd_code_size_limit(false);
jrose@1058:   VtableStub* s = new(i486_code_length) VtableStub(false, itable_index);
duke@435:   ResourceMark rm;
duke@435:   CodeBuffer cb(s->entry_point(), i486_code_length);
duke@435:   MacroAssembler* masm = new MacroAssembler(&cb);
duke@435: 
duke@435:   // Entry arguments:
duke@435:   //  rax,: Interface
duke@435:   //  rcx: Receiver
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   if (CountCompiledCalls) {
never@739:     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
duke@435:   }
duke@435: #endif /* PRODUCT */
duke@435:   // get receiver (need to skip return address on top of stack)
duke@435: 
duke@435:   assert(VtableStub::receiver_location() == rcx->as_VMReg(), "receiver expected in rcx");
duke@435: 
duke@435:   // get receiver klass (also an implicit null-check)
duke@435:   address npe_addr = __ pc();
jrose@1058:   __ movptr(rsi, Address(rcx, oopDesc::klass_offset_in_bytes()));
duke@435: 
jrose@1058:   // Most registers are in use; we'll use rax, rbx, rsi, rdi
jrose@1058:   // (If we need to make rsi, rdi callee-save, do a push/pop here.)
jrose@1058:   const Register method = rbx;
jrose@1058:   Label throw_icce;
duke@435: 
duke@435:   // Get methodOop and entrypoint for compiler
jrose@1058:   __ lookup_interface_method(// inputs: rec. class, interface, itable index
jrose@1058:                              rsi, rax, itable_index,
jrose@1058:                              // outputs: method, scan temp. reg
jrose@1058:                              method, rdi,
jrose@1058:                              throw_icce);
duke@435: 
duke@435:   // method (rbx): methodOop
duke@435:   // rcx: receiver
duke@435: 
duke@435: #ifdef ASSERT
duke@435:   if (DebugVtables) {
duke@435:       Label L1;
never@739:       __ cmpptr(method, (int32_t)NULL_WORD);
duke@435:       __ jcc(Assembler::equal, L1);
never@739:       __ cmpptr(Address(method, methodOopDesc::from_compiled_offset()), (int32_t)NULL_WORD);
duke@435:       __ jcc(Assembler::notZero, L1);
duke@435:       __ stop("methodOop is null");
duke@435:       __ bind(L1);
duke@435:     }
duke@435: #endif // ASSERT
duke@435: 
duke@435:   address ame_addr = __ pc();
duke@435:   __ jmp(Address(method, methodOopDesc::from_compiled_offset()));
duke@435: 
dcubed@451:   __ bind(throw_icce);
dcubed@451:   __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
duke@435:   masm->flush();
dcubed@451: 
jrose@1058:   if (PrintMiscellaneous && (WizardMode || Verbose)) {
jrose@1058:     tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",
jrose@1058:                   itable_index, s->entry_point(),
jrose@1058:                   (int)(s->code_end() - s->entry_point()),
jrose@1058:                   (int)(s->code_end() - __ pc()));
jrose@1058:   }
dcubed@451:   guarantee(__ pc() <= s->code_end(), "overflowed buffer");
jrose@1144:   // shut the door on sizing bugs
jrose@1144:   int slop = 3;  // 32-bit offset is this much larger than an 8-bit one
jrose@1144:   assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for 32-bit offset");
dcubed@451: 
duke@435:   s->set_exception_points(npe_addr, ame_addr);
duke@435:   return s;
duke@435: }
duke@435: 
duke@435: 
duke@435: 
duke@435: int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
duke@435:   if (is_vtable_stub) {
duke@435:     // Vtable stub size
duke@435:     return (DebugVtables ? 210 : 16) + (CountCompiledCalls ? 6 : 0);
duke@435:   } else {
duke@435:     // Itable stub size
jrose@1058:     return (DebugVtables ? 256 : 66) + (CountCompiledCalls ? 6 : 0);
duke@435:   }
jrose@1144:   // In order to tune these parameters, run the JVM with VM options
jrose@1144:   // +PrintMiscellaneous and +WizardMode to see information about
jrose@1144:   // actual itable stubs.  Look for lines like this:
jrose@1144:   //   itable #1 at 0x5551212[65] left over: 3
jrose@1144:   // Reduce the constants so that the "left over" number is >=3
jrose@1144:   // for the common cases.
jrose@1144:   // Do not aim at a left-over number of zero, because a
jrose@1144:   // large vtable or itable index (> 16) will require a 32-bit
jrose@1144:   // immediate displacement instead of an 8-bit one.
jrose@1144:   //
jrose@1144:   // The JVM98 app. _202_jess has a megamorphic interface call.
jrose@1144:   // The itable code looks like this:
jrose@1144:   // Decoding VtableStub itbl[1]@1
jrose@1144:   //   mov    0x4(%ecx),%esi
jrose@1144:   //   mov    0xe8(%esi),%edi
jrose@1144:   //   lea    0x130(%esi,%edi,4),%edi
jrose@1144:   //   add    $0x7,%edi
jrose@1144:   //   and    $0xfffffff8,%edi
jrose@1144:   //   lea    0x4(%esi),%esi
jrose@1144:   //   mov    (%edi),%ebx
jrose@1144:   //   cmp    %ebx,%eax
jrose@1144:   //   je     success
jrose@1144:   // loop:
jrose@1144:   //   test   %ebx,%ebx
jrose@1144:   //   je     throw_icce
jrose@1144:   //   add    $0x8,%edi
jrose@1144:   //   mov    (%edi),%ebx
jrose@1144:   //   cmp    %ebx,%eax
jrose@1144:   //   jne    loop
jrose@1144:   // success:
jrose@1144:   //   mov    0x4(%edi),%edi
jrose@1144:   //   mov    (%esi,%edi,1),%ebx
jrose@1144:   //   jmp    *0x44(%ebx)
jrose@1144:   // throw_icce:
jrose@1144:   //   jmp    throw_ICCE_entry
duke@435: }
duke@435: 
duke@435: int VtableStub::pd_code_alignment() {
duke@435:   return wordSize;
duke@435: }