1 /*
2 * Copyright (c) 2003, 2016, 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 // Can be NULL if there is no free space in the code cache.
55 if (s == NULL) {
56 return NULL;
57 }
58
59 ResourceMark rm;
60 CodeBuffer cb(s->entry_point(), aarch64_code_length);
61 MacroAssembler* masm = new MacroAssembler(&cb);
62
63 #ifndef PRODUCT
64 if (CountCompiledCalls) {
65 __ lea(r19, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
66 __ incrementw(Address(r19));
67 }
68 #endif
69
70 // get receiver (need to skip return address on top of stack)
71 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
72
73 // get receiver klass
74 address npe_addr = __ pc();
75 __ load_klass(r19, j_rarg0);
76
77 #ifndef PRODUCT
78 if (DebugVtables) {
79 Label L;
80 // check offset vs vtable length
81 __ ldrw(rscratch1, Address(r19, Klass::vtable_length_offset()));
82 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
83 __ br(Assembler::GT, L);
84 __ enter();
85 __ mov(r2, vtable_index);
86 __ call_VM(noreg,
87 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
88 __ leave();
89 __ bind(L);
90 }
91 #endif // PRODUCT
92
93 __ lookup_virtual_method(r19, vtable_index, rmethod);
94
95 if (DebugVtables) {
96 Label L;
97 __ cbz(rmethod, L);
98 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
99 __ cbnz(rscratch1, L);
100 __ stop("Vtable entry is NULL");
101 __ bind(L);
102 }
103 // r0: receiver klass
104 // rmethod: Method*
105 // r2: receiver
106 address ame_addr = __ pc();
107 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
108 __ br(rscratch1);
109
110 __ flush();
111
112 if (PrintMiscellaneous && (WizardMode || Verbose)) {
113 tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
114 vtable_index, p2i(s->entry_point()),
115 (int)(s->code_end() - s->entry_point()),
116 (int)(s->code_end() - __ pc()));
117 }
118 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
119
120 s->set_exception_points(npe_addr, ame_addr);
121 return s;
122 }
123
124
125 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
126 // Note well: pd_code_size_limit is the absolute minimum we can get
127 // away with. If you add code here, bump the code stub size
128 // returned by pd_code_size_limit!
129 const int code_length = VtableStub::pd_code_size_limit(false);
130 VtableStub* s = new(code_length) VtableStub(false, itable_index);
131 ResourceMark rm;
132 CodeBuffer cb(s->entry_point(), code_length);
133 MacroAssembler* masm = new MacroAssembler(&cb);
134
135 #ifndef PRODUCT
136 if (CountCompiledCalls) {
137 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
138 __ incrementw(Address(r10));
139 }
140 #endif
141
142 // Entry arguments:
143 // rscratch2: Interface
144 // j_rarg0: Receiver
145
146 // Free registers (non-args) are r0 (interface), rmethod
147
148 // get receiver (need to skip return address on top of stack)
149
150 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
151 // get receiver klass (also an implicit null-check)
152 address npe_addr = __ pc();
153
154 // Most registers are in use; we'll use r0, rmethod, r10, r11
155 __ load_klass(r10, j_rarg0);
156
157 Label throw_icce;
158
159 // Get Method* and entrypoint for compiler
160 __ lookup_interface_method(// inputs: rec. class, interface, itable index
161 r10, rscratch2, itable_index,
162 // outputs: method, scan temp. reg
163 rmethod, r11,
164 throw_icce);
165
166 // method (rmethod): Method*
167 // j_rarg0: receiver
168
169 #ifdef ASSERT
170 if (DebugVtables) {
171 Label L2;
172 __ cbz(rmethod, L2);
173 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
174 __ cbnz(rscratch1, L2);
175 __ stop("compiler entrypoint is null");
176 __ bind(L2);
177 }
178 #endif // ASSERT
179
180 // rmethod: Method*
181 // j_rarg0: receiver
182 address ame_addr = __ pc();
183 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
184 __ br(rscratch1);
185
186 __ bind(throw_icce);
187 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
188
189 __ flush();
190
191 if (PrintMiscellaneous && (WizardMode || Verbose)) {
192 tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
193 itable_index, p2i(s->entry_point()),
194 (int)(s->code_end() - s->entry_point()),
195 (int)(s->code_end() - __ pc()));
196 }
197 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
198
199 s->set_exception_points(npe_addr, ame_addr);
200 return s;
201 }
202
203
204 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
205 int size = DebugVtables ? 216 : 0;
206 if (CountCompiledCalls)
207 size += 6 * 4;
208 // FIXME
209 if (is_vtable_stub)
210 size += 52;
211 else
212 size += 104;
213 return size;
214
215 // In order to tune these parameters, run the JVM with VM options
216 // +PrintMiscellaneous and +WizardMode to see information about
217 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
218 //
219 // If Universe::narrow_klass_base is nonzero, decoding a compressed
220 // class can take zeveral instructions. Run it with -Xmx31G
221 // -XX:+UseCompressedOops.
222 //
223 // The JVM98 app. _202_jess has a megamorphic interface call.
224 // The itable code looks like this:
225 // Decoding VtableStub itbl[1]@12
226 // ldr w10, [x1,#8]
227 // lsl x10, x10, #3
228 // ldr w11, [x10,#280]
229 // add x11, x10, x11, uxtx #3
230 // add x11, x11, #0x1b8
231 // ldr x12, [x11]
232 // cmp x9, x12
233 // b.eq success
234 // loop:
235 // cbz x12, throw_icce
236 // add x11, x11, #0x10
237 // ldr x12, [x11]
238 // cmp x9, x12
239 // b.ne loop
240 // success:
241 // ldr x11, [x11,#8]
242 // ldr x12, [x10,x11]
243 // ldr x8, [x12,#72]
244 // br x8
245 // throw_icce:
246 // b throw_ICCE_entry
247
248 }
249
250 int VtableStub::pd_code_alignment() { return 4; }