duke@435: /* dbuck@8997: * Copyright (c) 1997, 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: 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); 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(), 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())); twisti@3969: 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), 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: coleenp@4037: // load Method* and target address 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: duke@435: // rax,: receiver klass coleenp@4037: // method (rbx): Method* duke@435: // rcx: receiver duke@435: address ame_addr = __ pc(); coleenp@4037: __ jmp( Address(method, Method::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", drchase@6680: vtable_index, p2i(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); 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(), i486_code_length); duke@435: MacroAssembler* masm = new MacroAssembler(&cb); duke@435: duke@435: // Entry arguments: dbuck@8997: // rax: CompiledICHolder 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: dbuck@8997: // Most registers are in use; we'll use rax, rbx, rsi, rdi dbuck@8997: // (If we need to make rsi, rdi callee-save, do a push/pop here.) dbuck@8997: const Register recv_klass_reg = rsi; 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 = rdi; 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: Label L_no_such_interface; duke@435: duke@435: // get receiver klass (also an implicit null-check) duke@435: address npe_addr = __ pc(); dbuck@8997: assert(VtableStub::receiver_location() == rcx->as_VMReg(), "receiver expected in rcx"); dbuck@8997: __ load_klass(recv_klass_reg, rcx); duke@435: 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 jrose@1058: const Register method = rbx; dbuck@8997: __ load_klass(recv_klass_reg, rcx); // restore recv_klass_reg jrose@1058: __ lookup_interface_method(// inputs: rec. class, interface, itable index dbuck@8997: recv_klass_reg, holder_klass_reg, itable_index, jrose@1058: // outputs: method, scan temp. reg dbuck@8997: method, temp_reg, dbuck@8997: L_no_such_interface); duke@435: coleenp@4037: // method (rbx): Method* 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); coleenp@4037: __ cmpptr(Address(method, Method::from_compiled_offset()), (int32_t)NULL_WORD); duke@435: __ jcc(Assembler::notZero, L1); coleenp@4037: __ stop("Method* is null"); duke@435: __ bind(L1); duke@435: } duke@435: #endif // ASSERT duke@435: duke@435: address ame_addr = __ pc(); coleenp@4037: __ jmp(Address(method, Method::from_compiled_offset())); duke@435: dbuck@8997: __ bind(L_no_such_interface); dcubed@451: __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry())); dbuck@8997: dbuck@8997: __ flush(); dcubed@451: jrose@1058: if (PrintMiscellaneous && (WizardMode || Verbose)) { jrose@1058: tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d", drchase@6680: itable_index, p2i(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 dbuck@8997: return (DebugVtables ? 256 : 116) + (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: }