1 /*
2 * Copyright (c) 2014, 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/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 ResourceMark rm;
56 CodeBuffer cb(s->entry_point(), aarch64_code_length);
57 MacroAssembler* masm = new MacroAssembler(&cb);
58
59 #ifndef PRODUCT
60 if (CountCompiledCalls) {
61 __ lea(r19, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
62 __ incrementw(Address(r19));
63 }
64 #endif
65
66 // get receiver (need to skip return address on top of stack)
67 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
68
69 // get receiver klass
70 address npe_addr = __ pc();
71 __ load_klass(r19, j_rarg0);
72
73 #ifndef PRODUCT
74 if (DebugVtables) {
75 Label L;
76 // check offset vs vtable length
77 __ ldrw(rscratch1, Address(r19, InstanceKlass::vtable_length_offset() * wordSize));
78 __ cmpw(rscratch1, vtable_index * vtableEntry::size());
79 __ br(Assembler::GT, L);
80 __ enter();
81 __ mov(r2, vtable_index);
82 __ call_VM(noreg,
83 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, r2);
84 __ leave();
85 __ bind(L);
86 }
87 #endif // PRODUCT
88
89 __ lookup_virtual_method(r19, vtable_index, rmethod);
90
91 if (DebugVtables) {
92 Label L;
93 __ cbz(rmethod, L);
94 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
95 __ cbnz(rscratch1, L);
96 __ stop("Vtable entry is NULL");
97 __ bind(L);
98 }
99 // r0: receiver klass
100 // rmethod: Method*
101 // r2: receiver
102 address ame_addr = __ pc();
103 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
104 __ br(rscratch1);
105
106 __ flush();
107
108 if (PrintMiscellaneous && (WizardMode || Verbose)) {
109 tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",
110 vtable_index, p2i(s->entry_point()),
111 (int)(s->code_end() - s->entry_point()),
112 (int)(s->code_end() - __ pc()));
113 }
114 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
115
116 s->set_exception_points(npe_addr, ame_addr);
117 return s;
118 }
119
120
121 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
122 // Note well: pd_code_size_limit is the absolute minimum we can get
123 // away with. If you add code here, bump the code stub size
124 // returned by pd_code_size_limit!
125 const int code_length = VtableStub::pd_code_size_limit(false);
126 VtableStub* s = new(code_length) VtableStub(false, itable_index);
127 ResourceMark rm;
128 CodeBuffer cb(s->entry_point(), code_length);
129 MacroAssembler* masm = new MacroAssembler(&cb);
130
131 #ifndef PRODUCT
132 if (CountCompiledCalls) {
133 __ lea(r10, ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
134 __ incrementw(Address(r10));
135 }
136 #endif
137
138 // Entry arguments:
139 // rscratch2: Interface
140 // j_rarg0: Receiver
141
142 // Free registers (non-args) are r0 (interface), rmethod
143
144 // get receiver (need to skip return address on top of stack)
145
146 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
147 // get receiver klass (also an implicit null-check)
148 address npe_addr = __ pc();
149
150 // Most registers are in use; we'll use r0, rmethod, r10, r11
151 __ load_klass(r10, j_rarg0);
152
153 Label throw_icce;
154
155 // Get Method* and entrypoint for compiler
156 __ lookup_interface_method(// inputs: rec. class, interface, itable index
157 r10, rscratch2, itable_index,
158 // outputs: method, scan temp. reg
159 rmethod, r11,
160 throw_icce);
161
162 // method (rmethod): Method*
163 // j_rarg0: receiver
164
165 #ifdef ASSERT
166 if (DebugVtables) {
167 Label L2;
168 __ cbz(rmethod, L2);
169 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
170 __ cbnz(rscratch1, L2);
171 __ stop("compiler entrypoint is null");
172 __ bind(L2);
173 }
174 #endif // ASSERT
175
176 // rmethod: Method*
177 // j_rarg0: receiver
178 address ame_addr = __ pc();
179 __ ldr(rscratch1, Address(rmethod, Method::from_compiled_offset()));
180 __ br(rscratch1);
181
182 __ bind(throw_icce);
183 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
184
185 __ flush();
186
187 if (PrintMiscellaneous && (WizardMode || Verbose)) {
188 tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",
189 itable_index, p2i(s->entry_point()),
190 (int)(s->code_end() - s->entry_point()),
191 (int)(s->code_end() - __ pc()));
192 }
193 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
194
195 s->set_exception_points(npe_addr, ame_addr);
196 return s;
197 }
198
199
200 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
201 int size = DebugVtables ? 216 : 0;
202 if (CountCompiledCalls)
203 size += 6 * 4;
204 // FIXME
205 if (is_vtable_stub)
206 size += 52;
207 else
208 size += 104;
209 return size;
210
211 // In order to tune these parameters, run the JVM with VM options
212 // +PrintMiscellaneous and +WizardMode to see information about
213 // actual itable stubs. Run it with -Xmx31G -XX:+UseCompressedOops.
214 //
215 // If Universe::narrow_klass_base is nonzero, decoding a compressed
216 // class can take zeveral instructions. Run it with -Xmx31G
217 // -XX:+UseCompressedOops.
218 //
219 // The JVM98 app. _202_jess has a megamorphic interface call.
220 // The itable code looks like this:
221 // Decoding VtableStub itbl[1]@12
222 // ldr w10, [x1,#8]
223 // lsl x10, x10, #3
224 // ldr w11, [x10,#280]
225 // add x11, x10, x11, uxtx #3
226 // add x11, x11, #0x1b8
227 // ldr x12, [x11]
228 // cmp x9, x12
229 // b.eq success
230 // loop:
231 // cbz x12, throw_icce
232 // add x11, x11, #0x10
233 // ldr x12, [x11]
234 // cmp x9, x12
235 // b.ne loop
236 // success:
237 // ldr x11, [x11,#8]
238 // ldr x12, [x10,x11]
239 // ldr x8, [x12,#72]
240 // br x8
241 // throw_icce:
242 // b throw_ICCE_entry
243
244 }
245
246 int VtableStub::pd_code_alignment() { return 4; }