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/compiledICHolder.hpp"
33 #include "oops/instanceKlass.hpp"
34 #include "oops/klassVtable.hpp"
35 #include "runtime/sharedRuntime.hpp"
36 #include "vmreg_aarch64.inline.hpp"
37 #ifdef COMPILER2
38 #include "opto/runtime.hpp"
39 #endif
40
41 // machine-dependent part of VtableStubs: create VtableStub of correct size and
42 // initialize its code
43
44 #define __ masm->
45
46 #ifndef PRODUCT
47 extern "C" void bad_compiled_vtable_index(JavaThread* thread,
48 oop receiver,
49 int index);
50 #endif
51
52 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
53 const int aarch64_code_length = VtableStub::pd_code_size_limit(true);
54 VtableStub* s = new(aarch64_code_length) VtableStub(true, vtable_index);
55 // Can be NULL if there is no free space in the code cache.
56 if (s == NULL) {
57 return NULL;
58 }
59
60 ResourceMark rm;
61 CodeBuffer cb(s->entry_point(), aarch64_code_length);
62 MacroAssembler* masm = new MacroAssembler(&cb);
63
64 #ifndef PRODUCT
65 if (CountCompiledCalls) {
66 __ lea(r16, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
67 __ incrementw(Address(r16));
68 }
69 #endif
70
71 // get receiver (need to skip return address on top of stack)
72 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
73
74 // get receiver klass
75 address npe_addr = __ pc();
76 __ load_klass(r16, j_rarg0);
77
78 #ifndef PRODUCT
79 if (DebugVtables) {
80 Label L;
81 // check offset vs vtable length
82 __ ldrw(rscratch1, Address(r16, Klass::vtable_length_offset()));
83 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
84 __ br(Assembler::GT, L);
85 __ enter();
86 __ mov(r2, vtable_index);
87 __ call_VM(noreg,
88 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
89 __ leave();
90 __ bind(L);
91 }
92 #endif // PRODUCT
93
94 __ lookup_virtual_method(r16, vtable_index, rmethod);
95
96 if (DebugVtables) {
97 Label L;
98 __ cbz(rmethod, L);
99 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
100 __ cbnz(rscratch1, L);
101 __ stop("Vtable entry is NULL");
102 __ bind(L);
103 }
104 // r0: receiver klass
105 // rmethod: Method*
106 // r2: receiver
107 address ame_addr = __ pc();
108 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
109 __ br(rscratch1);
110
111 __ flush();
112
113 if (PrintMiscellaneous && (WizardMode || Verbose)) {
114 tty->print_cr("vtable #%d at " PTR_FORMAT "[%d] left over: %d",
115 vtable_index, p2i(s->entry_point()),
116 (int)(s->code_end() - s->entry_point()),
117 (int)(s->code_end() - __ pc()));
118 }
119 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
120
121 s->set_exception_points(npe_addr, ame_addr);
122 return s;
123 }
124
125
126 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
127 // Note well: pd_code_size_limit is the absolute minimum we can get
128 // away with. If you add code here, bump the code stub size
129 // returned by pd_code_size_limit!
130 const int code_length = VtableStub::pd_code_size_limit(false);
131 VtableStub* s = new(code_length) VtableStub(false, itable_index);
132 ResourceMark rm;
133 CodeBuffer cb(s->entry_point(), code_length);
134 MacroAssembler* masm = new MacroAssembler(&cb);
135
136 #ifndef PRODUCT
137 if (CountCompiledCalls) {
138 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
139 __ incrementw(Address(r10));
140 }
141 #endif
142
143 // Entry arguments:
144 // rscratch2: CompiledICHolder
145 // j_rarg0: Receiver
146
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 Label L_no_such_interface;
156
157 __ ldr(resolved_klass_reg, Address(icholder_reg, CompiledICHolder::holder_klass_offset()));
158 __ ldr(holder_klass_reg, Address(icholder_reg, CompiledICHolder::holder_metadata_offset()));
159
160 // get receiver (need to skip return address on top of stack)
161 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
162 // get receiver klass (also an implicit null-check)
163 address npe_addr = __ pc();
164 __ load_klass(recv_klass_reg, j_rarg0);
165
166 // Receiver subtype check against REFC.
167 // Destroys recv_klass_reg value.
168 __ lookup_interface_method(// inputs: rec. class, interface
169 recv_klass_reg, resolved_klass_reg, noreg,
170 // outputs: scan temp. reg1, scan temp. reg2
171 recv_klass_reg, temp_reg,
172 L_no_such_interface,
173 /*return_method=*/false);
174
175 // Get selected method from declaring class and itable index
176 __ load_klass(recv_klass_reg, j_rarg0); // restore recv_klass_reg
177 __ lookup_interface_method(// inputs: rec. class, interface, itable index
178 recv_klass_reg, holder_klass_reg, itable_index,
179 // outputs: method, scan temp. reg
180 rmethod, temp_reg,
181 L_no_such_interface);
182
183 // method (rmethod): Method*
184 // j_rarg0: receiver
185
186 #ifdef ASSERT
187 if (DebugVtables) {
188 Label L2;
189 __ cbz(rmethod, L2);
190 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
191 __ cbnz(rscratch1, L2);
192 __ stop("compiler entrypoint is null");
193 __ bind(L2);
194 }
195 #endif // ASSERT
196
197 // rmethod: Method*
198 // j_rarg0: receiver
199 address ame_addr = __ pc();
200 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
201 __ br(rscratch1);
202
203 __ bind(L_no_such_interface);
204 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
205
206 __ flush();
207
208 if (PrintMiscellaneous && (WizardMode || Verbose)) {
209 tty->print_cr("itable #%d at " PTR_FORMAT "[%d] left over: %d",
210 itable_index, p2i(s->entry_point()),
211 (int)(s->code_end() - s->entry_point()),
212 (int)(s->code_end() - __ pc()));
213 }
214 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
215
216 s->set_exception_points(npe_addr, ame_addr);
217 return s;
218 }
219
220
221 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
222 int size = DebugVtables ? 216 : 0;
223 if (CountCompiledCalls)
224 size += 6 * 4;
225 // FIXME: vtable stubs only need 36 bytes
226 if (is_vtable_stub)
227 size += 52;
228 else
229 size += 176;
230 return size;
231
232 // In order to tune these parameters, run the JVM with VM options
233 // +PrintMiscellaneous and +WizardMode to see information about
234 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
235 //
236 // If Universe::narrow_klass_base is nonzero, decoding a compressed
237 // class can take zeveral instructions.
238 //
239 // The JVM98 app. _202_jess has a megamorphic interface call.
240 // The itable code looks like this:
241
242 // ldr xmethod, [xscratch2,#CompiledICHolder::holder_klass_offset]
243 // ldr x0, [xscratch2]
244 // ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
245 // mov xheapbase, #0x3c000000 // #narrow_klass_base
246 // movk xheapbase, #0x3f7, lsl #32
247 // add x10, xheapbase, x10
248 // mov xheapbase, #0xe7ff0000 // #heapbase
249 // movk xheapbase, #0x3f7, lsl #32
250 // ldr w11, [x10,#vtable_length_offset]
251 // add x11, x10, x11, uxtx #3
252 // add x11, x11, #itableMethodEntry::method_offset_in_bytes
253 // ldr x10, [x11]
254 // cmp xmethod, x10
255 // b.eq found_method
256 // search:
257 // cbz x10, no_such_interface
258 // add x11, x11, #0x10
259 // ldr x10, [x11]
260 // cmp xmethod, x10
261 // b.ne search
262 // found_method:
263 // ldr w10, [x1,#oopDesc::klass_offset_in_bytes]
264 // mov xheapbase, #0x3c000000 // #narrow_klass_base
265 // movk xheapbase, #0x3f7, lsl #32
266 // add x10, xheapbase, x10
267 // mov xheapbase, #0xe7ff0000 // #heapbase
268 // movk xheapbase, #0x3f7, lsl #32
269 // ldr w11, [x10,#vtable_length_offset]
270 // add x11, x10, x11, uxtx #3
271 // add x11, x11, #itableMethodEntry::method_offset_in_bytes
272 // add x10, x10, #itentry_off
273 // ldr xmethod, [x11]
274 // cmp x0, xmethod
275 // b.eq found_method2
276 // search2:
277 // cbz xmethod, 0x000003ffa872e6cc
278 // add x11, x11, #0x10
279 // ldr xmethod, [x11]
280 // cmp x0, xmethod
281 // b.ne search2
282 // found_method2:
283 // ldr w11, [x11,#itableOffsetEntry::offset_offset_in_bytes]
284 // ldr xmethod, [x10,w11,uxtw]
285 // ldr xscratch1, [xmethod,#Method::from_compiled_offset]
286 // br xscratch1
287 // no_such_interface:
288 // b throw_ICCE_entry
289
290 }
291
292 int VtableStub::pd_code_alignment() { return 4; }