1 /*
2 * Copyright (c) 2003, 2010, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "asm/macroAssembler.hpp"
28 #include "assembler_aarch64.inline.hpp"
29 #include "code/vtableStubs.hpp"
30 #include "interp_masm_aarch64.hpp"
31 #include "memory/resourceArea.hpp"
32 #include "oops/instanceKlass.hpp"
33 #include "oops/klassVtable.hpp"
34 #include "runtime/sharedRuntime.hpp"
35 #include "vmreg_aarch64.inline.hpp"
36 #ifdef COMPILER2
37 #include "opto/runtime.hpp"
38 #endif
39
40 // machine-dependent part of VtableStubs: create VtableStub of correct size and
41 // initialize its code
42
43 #define __ masm->
44
45 #ifndef PRODUCT
46 extern "C" void bad_compiled_vtable_index(JavaThread* thread,
47 oop receiver,
48 int index);
49 #endif
50
51 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
52 const int aarch64_code_length = VtableStub::pd_code_size_limit(true);
53 VtableStub* s = new(aarch64_code_length) VtableStub(true, vtable_index);
54 ResourceMark rm;
55 CodeBuffer cb(s->entry_point(), aarch64_code_length);
56 MacroAssembler* masm = new MacroAssembler(&cb);
57
58 #ifndef PRODUCT
59 if (CountCompiledCalls) {
60 __ lea(r19, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
61 __ incrementw(Address(r19));
62 }
63 #endif
64
65 // get receiver (need to skip return address on top of stack)
66 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
67
68 // get receiver klass
69 address npe_addr = __ pc();
70 __ load_klass(r19, j_rarg0);
71
72 #ifndef PRODUCT
73 if (DebugVtables) {
74 Label L;
75 // check offset vs vtable length
76 __ ldrw(rscratch1, Address(r19, InstanceKlass::vtable_length_offset() * wordSize));
77 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
78 __ br(Assembler::GT, L);
79 __ enter();
80 __ mov(r2, vtable_index);
81 __ call_VM(noreg,
82 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
83 __ leave();
84 __ bind(L);
85 }
86 #endif // PRODUCT
87
88 __ lookup_virtual_method(r19, vtable_index, rmethod);
89
90 if (DebugVtables) {
91 Label L;
92 __ cbz(rmethod, L);
93 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
94 __ cbnz(rscratch1, L);
95 __ stop("Vtable entry is NULL");
96 __ bind(L);
97 }
98 // r0: receiver klass
99 // rmethod: Method*
100 // r2: receiver
101 address ame_addr = __ pc();
102 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
103 __ br(rscratch1);
104
105 __ flush();
106
107 if (PrintMiscellaneous && (WizardMode || Verbose)) {
108 tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
109 vtable_index, p2i(s->entry_point()),
110 (int)(s->code_end() - s->entry_point()),
111 (int)(s->code_end() - __ pc()));
112 }
113 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
114
115 s->set_exception_points(npe_addr, ame_addr);
116 return s;
117 }
118
119
120 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
121 // Note well: pd_code_size_limit is the absolute minimum we can get
122 // away with. If you add code here, bump the code stub size
123 // returned by pd_code_size_limit!
124 const int code_length = VtableStub::pd_code_size_limit(false);
125 VtableStub* s = new(code_length) VtableStub(false, itable_index);
126 ResourceMark rm;
127 CodeBuffer cb(s->entry_point(), code_length);
128 MacroAssembler* masm = new MacroAssembler(&cb);
129
130 #ifndef PRODUCT
131 if (CountCompiledCalls) {
132 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
133 __ incrementw(Address(r10));
134 }
135 #endif
136
137 // Entry arguments:
138 // rscratch2: Interface
139 // j_rarg0: Receiver
140
141 // Free registers (non-args) are r0 (interface), rmethod
142
143 // get receiver (need to skip return address on top of stack)
144
145 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
146 // get receiver klass (also an implicit null-check)
147 address npe_addr = __ pc();
148
149 // Most registers are in use; we'll use r0, rmethod, r10, r11
150 __ load_klass(r10, j_rarg0);
151
152 Label throw_icce;
153
154 // Get Method* and entrypoint for compiler
155 __ lookup_interface_method(// inputs: rec. class, interface, itable index
156 r10, rscratch2, itable_index,
157 // outputs: method, scan temp. reg
158 rmethod, r11,
159 throw_icce);
160
161 // method (rmethod): Method*
162 // j_rarg0: receiver
163
164 #ifdef ASSERT
165 if (DebugVtables) {
166 Label L2;
167 __ cbz(rmethod, L2);
168 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
169 __ cbnz(rscratch1, L2);
170 __ stop("compiler entrypoint is null");
171 __ bind(L2);
172 }
173 #endif // ASSERT
174
175 // rmethod: Method*
176 // j_rarg0: receiver
177 address ame_addr = __ pc();
178 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
179 __ br(rscratch1);
180
181 __ bind(throw_icce);
182 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
183
184 __ flush();
185
186 if (PrintMiscellaneous && (WizardMode || Verbose)) {
187 tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
188 itable_index, p2i(s->entry_point()),
189 (int)(s->code_end() - s->entry_point()),
190 (int)(s->code_end() - __ pc()));
191 }
192 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
193
194 s->set_exception_points(npe_addr, ame_addr);
195 return s;
196 }
197
198
199 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
200 int size = DebugVtables ? 216 : 0;
201 if (CountCompiledCalls)
202 size += 6 * 4;
203 // FIXME
204 if (is_vtable_stub)
205 size += 52;
206 else
207 size += 104;
208 return size;
209
210 // In order to tune these parameters, run the JVM with VM options
211 // +PrintMiscellaneous and +WizardMode to see information about
212 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
213 //
214 // If Universe::narrow_klass_base is nonzero, decoding a compressed
215 // class can take zeveral instructions. Run it with -Xmx31G
216 // -XX:+UseCompressedOops.
217 //
218 // The JVM98 app. _202_jess has a megamorphic interface call.
219 // The itable code looks like this:
220 // Decoding VtableStub itbl[1]@12
221 // ldr w10, [x1,#8]
222 // lsl x10, x10, #3
223 // ldr w11, [x10,#280]
224 // add x11, x10, x11, uxtx #3
225 // add x11, x11, #0x1b8
226 // ldr x12, [x11]
227 // cmp x9, x12
228 // b.eq success
229 // loop:
230 // cbz x12, throw_icce
231 // add x11, x11, #0x10
232 // ldr x12, [x11]
233 // cmp x9, x12
234 // b.ne loop
235 // success:
236 // ldr x11, [x11,#8]
237 // ldr x12, [x10,x11]
238 // ldr x8, [x12,#72]
239 // br x8
240 // throw_icce:
241 // b throw_ICCE_entry
242
243 }
244
245 int VtableStub::pd_code_alignment() { return 4; }