1 /*
2 * Copyright (c) 2013, Red Hat Inc.
3 * Copyright (c) 2003, 2010, Oracle and/or its affiliates.
4 * All rights reserved.
5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 *
7 * This code is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 only, as
9 * published by the Free Software Foundation.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 *
25 */
26
27 #include "precompiled.hpp"
28 #include "asm/macroAssembler.hpp"
29 #include "assembler_aarch64.inline.hpp"
30 #include "code/vtableStubs.hpp"
31 #include "interp_masm_aarch64.hpp"
32 #include "memory/resourceArea.hpp"
33 #include "oops/compiledICHolder.hpp"
34 #include "oops/instanceKlass.hpp"
35 #include "oops/klassVtable.hpp"
36 #include "runtime/sharedRuntime.hpp"
37 #include "vmreg_aarch64.inline.hpp"
38 #ifdef COMPILER2
39 #include "opto/runtime.hpp"
40 #endif
41
42 // machine-dependent part of VtableStubs: create VtableStub of correct size and
43 // initialize its code
44
45 #define __ masm->
46
47 #ifndef PRODUCT
48 extern "C" void bad_compiled_vtable_index(JavaThread* thread,
49 oop receiver,
50 int index);
51 #endif
52
53 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
54 const int aarch64_code_length = VtableStub::pd_code_size_limit(true);
55 VtableStub* s = new(aarch64_code_length) VtableStub(true, vtable_index);
56 // Can be NULL if there is no free space in the code cache.
57 if (s == NULL) {
58 return NULL;
59 }
60
61 ResourceMark rm;
62 CodeBuffer cb(s->entry_point(), aarch64_code_length);
63 MacroAssembler* masm = new MacroAssembler(&cb);
64
65 #ifndef PRODUCT
66 if (CountCompiledCalls) {
67 __ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
68 __ incrementw(Address(r16));
69 }
70 #endif
71
72 // get receiver (need to skip return address on top of stack)
73 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
74
75 // get receiver klass
76 address npe_addr = __ pc();
77 __ load_klass(r16, j_rarg0);
78
79 #ifndef PRODUCT
80 if (DebugVtables) {
81 Label L;
82 // check offset vs vtable length
83 __ ldrw(rscratch1, Address(r16, InstanceKlass::vtable_length_offset() * wordSize));
84 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
85 __ br(Assembler::GT, L);
86 __ enter();
87 __ mov(r2, vtable_index);
88 __ call_VM(noreg,
89 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
90 __ leave();
91 __ bind(L);
92 }
93 #endif // PRODUCT
94
95 __ lookup_virtual_method(r16, vtable_index, rmethod);
96
97 if (DebugVtables) {
98 Label L;
99 __ cbz(rmethod, L);
100 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
101 __ cbnz(rscratch1, L);
102 __ stop("Vtable entry is NULL");
103 __ bind(L);
104 }
105 // r0: receiver klass
106 // rmethod: Method*
107 // r2: receiver
108 address ame_addr = __ pc();
109 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
110 __ br(rscratch1);
111
112 __ flush();
113
114 if (PrintMiscellaneous && (WizardMode || Verbose)) {
115 tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",
116 vtable_index, p2i(s->entry_point()),
117 (int)(s->code_end() - s->entry_point()),
118 (int)(s->code_end() - __ pc()));
119 }
120 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
121
122 s->set_exception_points(npe_addr, ame_addr);
123 return s;
124 }
125
126
127 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
128 // Note well: pd_code_size_limit is the absolute minimum we can get
129 // away with. If you add code here, bump the code stub size
130 // returned by pd_code_size_limit!
131 const int code_length = VtableStub::pd_code_size_limit(false);
132 VtableStub* s = new(code_length) VtableStub(false, itable_index);
133 ResourceMark rm;
134 CodeBuffer cb(s->entry_point(), code_length);
135 MacroAssembler* masm = new MacroAssembler(&cb);
136
137 #ifndef PRODUCT
138 if (CountCompiledCalls) {
139 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
140 __ incrementw(Address(r10));
141 }
142 #endif
143
144 // Entry arguments:
145 // rscratch2: CompiledICHolder
146 // j_rarg0: Receiver
147
148 // Most registers are in use; we'll use r16, rmethod, r10, r11
149 const Register recv_klass_reg = r10;
150 const Register holder_klass_reg = r16; // declaring interface klass (DECC)
151 const Register resolved_klass_reg = rmethod; // resolved interface klass (REFC)
152 const Register temp_reg = r11;
153 const Register icholder_reg = rscratch2;
154
155 __ ldr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
156 __ ldr(holder_klass_reg, Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
157
158 Label L_no_such_interface;
159
160 // get receiver klass (also an implicit null-check)
161 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
162 address npe_addr = __ pc();
163 __ load_klass(recv_klass_reg, j_rarg0);
164
165 // Receiver subtype check against REFC.
166 // Destroys recv_klass_reg value.
167 __ lookup_interface_method(// inputs: rec. class, interface
168 recv_klass_reg, resolved_klass_reg, noreg,
169 // outputs: scan temp. reg1, scan temp. reg2
170 recv_klass_reg, temp_reg,
171 L_no_such_interface,
172 /*return_method=*/false);
173
174 // Get selected method from declaring class and itable index
175 __ load_klass(recv_klass_reg, j_rarg0); // restore recv_klass_reg
176 __ lookup_interface_method(// inputs: rec. class, interface, itable index
177 recv_klass_reg, holder_klass_reg, itable_index,
178 // outputs: method, scan temp. reg
179 rmethod, temp_reg,
180 L_no_such_interface);
181
182 // method (rmethod): Method*
183 // j_rarg0: receiver
184
185 #ifdef ASSERT
186 if (DebugVtables) {
187 Label L2;
188 __ cbz(rmethod, L2);
189 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
190 __ cbnz(rscratch1, L2);
191 __ stop("compiler entrypoint is null");
192 __ bind(L2);
193 }
194 #endif // ASSERT
195
196 // rmethod: Method*
197 // j_rarg0: receiver
198 address ame_addr = __ pc();
199 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
200 __ br(rscratch1);
201
202 __ bind(L_no_such_interface);
203 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
204
205 __ flush();
206
207 if (PrintMiscellaneous && (WizardMode || Verbose)) {
208 tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",
209 itable_index, p2i(s->entry_point()),
210 (int)(s->code_end() - s->entry_point()),
211 (int)(s->code_end() - __ pc()));
212 }
213 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
214
215 s->set_exception_points(npe_addr, ame_addr);
216 return s;
217 }
218
219
220 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
221 int size = DebugVtables ? 216 : 0;
222 if (CountCompiledCalls)
223 size += 6 * 4;
224 // FIXME: vtable stubs only need 36 bytes
225 if (is_vtable_stub)
226 size += 52;
227 else
228 size += 176;
229 return size;
230
231 // In order to tune these parameters, run the JVM with VM options
232 // +PrintMiscellaneous and +WizardMode to see information about
233 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
234 //
235 // If Universe::narrow_klass_base is nonzero, decoding a compressed
236 // class can take several instructions.
237 //
238 // The JVM98 app. _202_jess has a megamorphic interface call.
239 // The itable code looks like this:
240
241 // ldr xmethod, [xscratch2,#CompiledICHolder::holder_klass_offset]
242 // ldr x0, [xscratch2]
243 // ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
244 // mov xheapbase, #0x3c000000 // #narrow_klass_base
245 // movk xheapbase, #0x3f7, lsl #32
246 // add x10, xheapbase, x10
247 // mov xheapbase, #0xe7ff0000 // #heapbase
248 // movk xheapbase, #0x3f7, lsl #32
249 // ldr w11, [x10,#vtable_length_offset]
250 // add x11, x10, x11, uxtx #3
251 // add x11, x11, #itableMethodEntry::method_offset_in_bytes
252 // ldr x10, [x11]
253 // cmp xmethod, x10
254 // b.eq success
255 // search:
256 // cbz x10, no_such_interface
257 // add x11, x11, #0x10
258 // ldr x10, [x11]
259 // cmp xmethod, x10
260 // b.ne search
261 // success:
262 // ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
263 // mov xheapbase, #0x3c000000 // #narrow_klass_base
264 // movk xheapbase, #0x3f7, lsl #32
265 // add x10, xheapbase, x10
266 // mov xheapbase, #0xe7ff0000 // #heapbase
267 // movk xheapbase, #0x3f7, lsl #32
268 // ldr w11, [x10,#vtable_length_offset]
269 // add x11, x10, x11, uxtx #3
270 // add x11, x11, #itableMethodEntry::method_offset_in_bytes
271 // add x10, x10, #itentry_off
272 // ldr xmethod, [x11]
273 // cmp x0, xmethod
274 // b.eq found_method
275 // search2:
276 // cbz xmethod, 0x000003ffa872e6cc
277 // add x11, x11, #0x10
278 // ldr xmethod, [x11]
279 // cmp x0, xmethod
280 // b.ne search2
281 // ldr w11, [x11,#itableOffsetEntry::offset_offset_in_bytes]
282 // ldr xmethod, [x10,w11,uxtw]
283 // ldr xscratch1, [xmethod,#Method::from_compiled_offset]
284 // br xscratch1
285 // no_such_interface:
286 // b throw_ICCE_entry
287
288 }
289
290 int VtableStub::pd_code_alignment() { return 4; }