8202676: AArch64: Missing enter/leave around barrier leads to infinite loop
Reviewed-by: aph, eosterlund
/*
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* Copyright (c) 2014, Red Hat Inc. 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.
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
#include "precompiled.hpp"
#include "asm/macroAssembler.hpp"
#include "assembler_aarch64.inline.hpp"
#include "code/vtableStubs.hpp"
#include "interp_masm_aarch64.hpp"
#include "memory/resourceArea.hpp"
#include "oops/compiledICHolder.hpp"
#include "oops/instanceKlass.hpp"
#include "oops/klassVtable.hpp"
#include "runtime/sharedRuntime.hpp"
#include "vmreg_aarch64.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
VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
const int aarch64_code_length = VtableStub::pd_code_size_limit(true);
VtableStub* s = new(aarch64_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(), aarch64_code_length);
MacroAssembler* masm = new MacroAssembler(&cb);
#ifndef PRODUCT
if (CountCompiledCalls) {
__ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
__ incrementw(Address(r16));
}
#endif
// get receiver (need to skip return address on top of stack)
assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
// get receiver klass
address npe_addr = __ pc();
__ load_klass(r16, j_rarg0);
#ifndef PRODUCT
if (DebugVtables) {
Label L;
// check offset vs vtable length
__ ldrw(rscratch1, Address(r16, Klass::vtable_length_offset()));
__ cmpw(rscratch1, vtable_index * vtableEntry::size());
__ br(Assembler::GT, L);
__ enter();
__ mov(r2, vtable_index);
__ call_VM(noreg,
CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
__ leave();
__ bind(L);
}
#endif // PRODUCT
__ lookup_virtual_method(r16, vtable_index, rmethod);
if (DebugVtables) {
Label L;
__ cbz(rmethod, L);
__ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
__ cbnz(rscratch1, L);
__ stop("Vtable entry is NULL");
__ bind(L);
}
// r0: receiver klass
// rmethod: Method*
// r2: receiver
address ame_addr = __ pc();
__ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
__ br(rscratch1);
__ 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");
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 code_length = VtableStub::pd_code_size_limit(false);
VtableStub* s = new(code_length) VtableStub(false, itable_index);
ResourceMark rm;
CodeBuffer cb(s->entry_point(), code_length);
MacroAssembler* masm = new MacroAssembler(&cb);
#ifndef PRODUCT
if (CountCompiledCalls) {
__ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
__ incrementw(Address(r10));
}
#endif
// Entry arguments:
// rscratch2: CompiledICHolder
// j_rarg0: Receiver
// Most registers are in use; we'll use r16, rmethod, r10, r11
const Register recv_klass_reg = r10;
const Register holder_klass_reg = r16; // declaring interface klass (DECC)
const Register resolved_klass_reg = rmethod; // resolved interface klass (REFC)
const Register temp_reg = r11;
const Register icholder_reg = rscratch2;
Label L_no_such_interface;
__ ldr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
__ ldr(holder_klass_reg, Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
// get receiver (need to skip return address on top of stack)
assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
// get receiver klass (also an implicit null-check)
address npe_addr = __ pc();
__ load_klass(recv_klass_reg, j_rarg0);
// 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
__ load_klass(recv_klass_reg, j_rarg0); // 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
rmethod, temp_reg,
L_no_such_interface);
// method (rmethod): Method*
// j_rarg0: receiver
#ifdef ASSERT
if (DebugVtables) {
Label L2;
__ cbz(rmethod, L2);
__ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
__ cbnz(rscratch1, L2);
__ stop("compiler entrypoint is null");
__ bind(L2);
}
#endif // ASSERT
// rmethod: Method*
// j_rarg0: receiver
address ame_addr = __ pc();
__ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
__ br(rscratch1);
__ bind(L_no_such_interface);
// Handle IncompatibleClassChangeError in itable stubs.
// More detailed error message.
// We force resolving of the call site by jumping to the "handle
// wrong method" stub, and so let the interpreter runtime do all the
// dirty work.
__ far_jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub()));
__ 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");
s->set_exception_points(npe_addr, ame_addr);
return s;
}
int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
int size = DebugVtables ? 216 : 0;
if (CountCompiledCalls)
size += 6 * 4;
// FIXME: vtable stubs only need 36 bytes
if (is_vtable_stub)
size += 52;
else
size += 176;
return size;
// In order to tune these parameters, run the JVM with VM options
// +PrintMiscellaneous and +WizardMode to see information about
// actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
//
// If Universe::narrow_klass_base is nonzero, decoding a compressed
// class can take zeveral instructions.
//
// The JVM98 app. _202_jess has a megamorphic interface call.
// The itable code looks like this:
// ldr xmethod, [xscratch2,#CompiledICHolder::holder_klass_offset]
// ldr x0, [xscratch2]
// ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
// mov xheapbase, #0x3c000000 // #narrow_klass_base
// movk xheapbase, #0x3f7, lsl #32
// add x10, xheapbase, x10
// mov xheapbase, #0xe7ff0000 // #heapbase
// movk xheapbase, #0x3f7, lsl #32
// ldr w11, [x10,#vtable_length_offset]
// add x11, x10, x11, uxtx #3
// add x11, x11, #itableMethodEntry::method_offset_in_bytes
// ldr x10, [x11]
// cmp xmethod, x10
// b.eq found_method
// search:
// cbz x10, no_such_interface
// add x11, x11, #0x10
// ldr x10, [x11]
// cmp xmethod, x10
// b.ne search
// found_method:
// ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
// mov xheapbase, #0x3c000000 // #narrow_klass_base
// movk xheapbase, #0x3f7, lsl #32
// add x10, xheapbase, x10
// mov xheapbase, #0xe7ff0000 // #heapbase
// movk xheapbase, #0x3f7, lsl #32
// ldr w11, [x10,#vtable_length_offset]
// add x11, x10, x11, uxtx #3
// add x11, x11, #itableMethodEntry::method_offset_in_bytes
// add x10, x10, #itentry_off
// ldr xmethod, [x11]
// cmp x0, xmethod
// b.eq found_method2
// search2:
// cbz xmethod, 0x000003ffa872e6cc
// add x11, x11, #0x10
// ldr xmethod, [x11]
// cmp x0, xmethod
// b.ne search2
// found_method2:
// ldr w11, [x11,#itableOffsetEntry::offset_offset_in_bytes]
// ldr xmethod, [x10,w11,uxtw]
// ldr xscratch1, [xmethod,#Method::from_compiled_offset]
// br xscratch1
// no_such_interface:
// b throw_ICCE_entry
}
int VtableStub::pd_code_alignment() { return 4; }