duke@435: /*
dbuck@8997:  * Copyright (c) 2003, 2017, Oracle and/or its affiliates. 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:  *
trims@1907:  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
trims@1907:  * or visit www.oracle.com if you need additional information or have any
trims@1907:  * questions.
duke@435:  *
duke@435:  */
duke@435: 
stefank@2314: #include "precompiled.hpp"
twisti@4318: #include "asm/macroAssembler.hpp"
stefank@2314: #include "code/vtableStubs.hpp"
roland@5987: #include "interp_masm_x86.hpp"
stefank@2314: #include "memory/resourceArea.hpp"
dbuck@8997: #include "oops/compiledICHolder.hpp"
stefank@2314: #include "oops/instanceKlass.hpp"
stefank@2314: #include "oops/klassVtable.hpp"
stefank@2314: #include "runtime/sharedRuntime.hpp"
stefank@2314: #include "vmreg_x86.inline.hpp"
stefank@2314: #ifdef COMPILER2
stefank@2314: #include "opto/runtime.hpp"
stefank@2314: #endif
duke@435: 
drchase@6680: PRAGMA_FORMAT_MUTE_WARNINGS_FOR_GCC
drchase@6680: 
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,
duke@435:                                           oop receiver,
duke@435:                                           int index);
duke@435: #endif
duke@435: 
duke@435: VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
duke@435:   const int amd64_code_length = VtableStub::pd_code_size_limit(true);
duke@435:   VtableStub* s = new(amd64_code_length) VtableStub(true, vtable_index);
anoll@5762:   // Can be NULL if there is no free space in the code cache.
anoll@5762:   if (s == NULL) {
anoll@5762:     return NULL;
anoll@5762:   }
anoll@5762: 
duke@435:   ResourceMark rm;
duke@435:   CodeBuffer cb(s->entry_point(), amd64_code_length);
duke@435:   MacroAssembler* masm = new MacroAssembler(&cb);
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   if (CountCompiledCalls) {
duke@435:     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
duke@435:   }
duke@435: #endif
duke@435: 
duke@435:   // get receiver (need to skip return address on top of stack)
duke@435:   assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
duke@435: 
duke@435:   // Free registers (non-args) are rax, rbx
duke@435: 
duke@435:   // get receiver klass
duke@435:   address npe_addr = __ pc();
coleenp@548:   __ load_klass(rax, j_rarg0);
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   if (DebugVtables) {
duke@435:     Label L;
duke@435:     // check offset vs vtable length
coleenp@4037:     __ cmpl(Address(rax, InstanceKlass::vtable_length_offset() * wordSize),
duke@435:             vtable_index * vtableEntry::size());
duke@435:     __ jcc(Assembler::greater, L);
duke@435:     __ movl(rbx, vtable_index);
duke@435:     __ call_VM(noreg,
duke@435:                CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, rbx);
duke@435:     __ bind(L);
duke@435:   }
duke@435: #endif // PRODUCT
duke@435: 
coleenp@4037:   // load Method* and target address
duke@435:   const Register method = rbx;
duke@435: 
twisti@3969:   __ lookup_virtual_method(rax, vtable_index, method);
twisti@3969: 
duke@435:   if (DebugVtables) {
duke@435:     Label L;
never@739:     __ cmpptr(method, (int32_t)NULL_WORD);
duke@435:     __ jcc(Assembler::equal, L);
coleenp@4037:     __ cmpptr(Address(method, Method::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:   // rax: receiver klass
coleenp@4037:   // rbx: Method*
duke@435:   // rcx: receiver
duke@435:   address ame_addr = __ pc();
coleenp@4037:   __ jmp( Address(rbx, Method::from_compiled_offset()));
duke@435: 
duke@435:   __ 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
duke@435:   // away with.  If you add code here, bump the code stub size
duke@435:   // returned by pd_code_size_limit!
duke@435:   const int amd64_code_length = VtableStub::pd_code_size_limit(false);
jrose@1058:   VtableStub* s = new(amd64_code_length) VtableStub(false, itable_index);
anoll@5762:   // Can be NULL if there is no free space in the code cache.
anoll@5762:   if (s == NULL) {
anoll@5762:     return NULL;
anoll@5762:   }
anoll@5762: 
duke@435:   ResourceMark rm;
duke@435:   CodeBuffer cb(s->entry_point(), amd64_code_length);
duke@435:   MacroAssembler* masm = new MacroAssembler(&cb);
duke@435: 
duke@435: #ifndef PRODUCT
duke@435:   if (CountCompiledCalls) {
duke@435:     __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
duke@435:   }
duke@435: #endif
duke@435: 
duke@435:   // Entry arguments:
dbuck@8997:   //  rax: CompiledICHolder
duke@435:   //  j_rarg0: Receiver
duke@435: 
jrose@1058:   // Most registers are in use; we'll use rax, rbx, r10, r11
jrose@1058:   // (various calling sequences use r[cd]x, r[sd]i, r[89]; stay away from them)
dbuck@8997:   const Register recv_klass_reg     = r10;
dbuck@8997:   const Register holder_klass_reg   = rax; // declaring interface klass (DECC)
dbuck@8997:   const Register resolved_klass_reg = rbx; // resolved interface klass (REFC)
dbuck@8997:   const Register temp_reg           = r11;
dbuck@8997: 
dbuck@8997:   Label L_no_such_interface;
dbuck@8997: 
dbuck@8997:   const Register icholder_reg = rax;
dbuck@8997:   __ movptr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
dbuck@8997:   __ movptr(holder_klass_reg,   Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
dbuck@8997: 
dbuck@8997:   // get receiver klass (also an implicit null-check)
dbuck@8997:   assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
dbuck@8997:   address npe_addr = __ pc();
dbuck@8997:   __ load_klass(recv_klass_reg, j_rarg0);
dbuck@8997: 
dbuck@8997:   // Receiver subtype check against REFC.
dbuck@8997:   // Destroys recv_klass_reg value.
dbuck@8997:   __ lookup_interface_method(// inputs: rec. class, interface
dbuck@8997:                              recv_klass_reg, resolved_klass_reg, noreg,
dbuck@8997:                              // outputs:  scan temp. reg1, scan temp. reg2
dbuck@8997:                              recv_klass_reg, temp_reg,
dbuck@8997:                              L_no_such_interface,
dbuck@8997:                              /*return_method=*/false);
dbuck@8997: 
dbuck@8997:   // Get selected method from declaring class and itable index
dbuck@8997:   const Register method = rbx;
dbuck@8997:   __ load_klass(recv_klass_reg, j_rarg0);   // restore recv_klass_reg
dbuck@8997:   __ lookup_interface_method(// inputs: rec. class, interface, itable index
dbuck@8997:                        recv_klass_reg, holder_klass_reg, itable_index,
dbuck@8997:                        // outputs: method, scan temp. reg
dbuck@8997:                        method, temp_reg,
dbuck@8997:                        L_no_such_interface);
duke@435: 
duke@435:   // If we take a trap while this arg is on the stack we will not
duke@435:   // be able to walk the stack properly. This is not an issue except
duke@435:   // when there are mistakes in this assembly code that could generate
duke@435:   // a spurious fault. Ask me how I know...
duke@435: 
coleenp@4037:   // method (rbx): Method*
duke@435:   // j_rarg0: receiver
duke@435: 
duke@435: #ifdef ASSERT
dcubed@451:   if (DebugVtables) {
dcubed@451:     Label L2;
never@739:     __ cmpptr(method, (int32_t)NULL_WORD);
dcubed@451:     __ jcc(Assembler::equal, L2);
coleenp@4037:     __ cmpptr(Address(method, Method::from_compiled_offset()), (int32_t)NULL_WORD);
dcubed@451:     __ jcc(Assembler::notZero, L2);
dcubed@451:     __ stop("compiler entrypoint is null");
dcubed@451:     __ bind(L2);
dcubed@451:   }
duke@435: #endif // ASSERT
duke@435: 
coleenp@4037:   // rbx: Method*
dcubed@451:   // j_rarg0: receiver
dcubed@451:   address ame_addr = __ pc();
coleenp@4037:   __ jmp(Address(method, Method::from_compiled_offset()));
dcubed@451: 
dbuck@8997:   __ bind(L_no_such_interface);
dcubed@451:   __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
duke@435: 
duke@435:   __ 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: int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
duke@435:   if (is_vtable_stub) {
duke@435:     // Vtable stub size
coleenp@548:     return (DebugVtables ? 512 : 24) + (CountCompiledCalls ? 13 : 0) +
ehelin@5694:            (UseCompressedClassPointers ?  MacroAssembler::instr_size_for_decode_klass_not_null() : 0);
duke@435:   } else {
duke@435:     // Itable stub size
dbuck@8997:     return (DebugVtables ? 512 : 140) + (CountCompiledCalls ? 13 : 0) +
dbuck@8997:            (UseCompressedClassPointers ? 2 * MacroAssembler::instr_size_for_decode_klass_not_null() : 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[71] 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 (>= 32) 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]@12
jrose@1144:   //   mov    0x8(%rsi),%r10
jrose@1144:   //   mov    0x198(%r10),%r11d
jrose@1144:   //   lea    0x218(%r10,%r11,8),%r11
jrose@1144:   //   lea    0x8(%r10),%r10
jrose@1144:   //   mov    (%r11),%rbx
jrose@1144:   //   cmp    %rbx,%rax
jrose@1144:   //   je     success
jrose@1144:   // loop:
jrose@1144:   //   test   %rbx,%rbx
jrose@1144:   //   je     throw_icce
jrose@1144:   //   add    $0x10,%r11
jrose@1144:   //   mov    (%r11),%rbx
jrose@1144:   //   cmp    %rbx,%rax
jrose@1144:   //   jne    loop
jrose@1144:   // success:
jrose@1144:   //   mov    0x8(%r11),%r11d
jrose@1144:   //   mov    (%r10,%r11,1),%rbx
jrose@1144:   //   jmpq   *0x60(%rbx)
jrose@1144:   // throw_icce:
jrose@1144:   //   jmpq   throw_ICCE_entry
duke@435: }
duke@435: 
duke@435: int VtableStub::pd_code_alignment() {
duke@435:   return wordSize;
duke@435: }