1 /*
2 * Copyright 2003-2008 Sun Microsystems, Inc. All Rights Reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
20 * CA 95054 USA or visit www.sun.com if you need additional information or
21 * have any questions.
22 *
23 */
24
25 #include "incls/_precompiled.incl"
26 #include "incls/_vtableStubs_x86_64.cpp.incl"
27
28 // machine-dependent part of VtableStubs: create VtableStub of correct size and
29 // initialize its code
30
31 #define __ masm->
32
33 #ifndef PRODUCT
34 extern "C" void bad_compiled_vtable_index(JavaThread* thread,
35 oop receiver,
36 int index);
37 #endif
38
39 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
40 const int amd64_code_length = VtableStub::pd_code_size_limit(true);
41 VtableStub* s = new(amd64_code_length) VtableStub(true, vtable_index);
42 ResourceMark rm;
43 CodeBuffer cb(s->entry_point(), amd64_code_length);
44 MacroAssembler* masm = new MacroAssembler(&cb);
45
46 #ifndef PRODUCT
47 if (CountCompiledCalls) {
48 __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
49 }
50 #endif
51
52 // get receiver (need to skip return address on top of stack)
53 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
54
55 // Free registers (non-args) are rax, rbx
56
57 // get receiver klass
58 address npe_addr = __ pc();
59 __ load_klass(rax, j_rarg0);
60
61 // compute entry offset (in words)
62 int entry_offset =
63 instanceKlass::vtable_start_offset() + vtable_index * vtableEntry::size();
64
65 #ifndef PRODUCT
66 if (DebugVtables) {
67 Label L;
68 // check offset vs vtable length
69 __ cmpl(Address(rax, instanceKlass::vtable_length_offset() * wordSize),
70 vtable_index * vtableEntry::size());
71 __ jcc(Assembler::greater, L);
72 __ movl(rbx, vtable_index);
73 __ call_VM(noreg,
74 CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), j_rarg0, rbx);
75 __ bind(L);
76 }
77 #endif // PRODUCT
78
79 // load methodOop and target address
80 const Register method = rbx;
81
82 __ movptr(method, Address(rax,
83 entry_offset * wordSize +
84 vtableEntry::method_offset_in_bytes()));
85 if (DebugVtables) {
86 Label L;
87 __ cmpptr(method, (int32_t)NULL_WORD);
88 __ jcc(Assembler::equal, L);
89 __ cmpptr(Address(method, methodOopDesc::from_compiled_offset()), (int32_t)NULL_WORD);
90 __ jcc(Assembler::notZero, L);
91 __ stop("Vtable entry is NULL");
92 __ bind(L);
93 }
94 // rax: receiver klass
95 // rbx: methodOop
96 // rcx: receiver
97 address ame_addr = __ pc();
98 __ jmp( Address(rbx, methodOopDesc::from_compiled_offset()));
99
100 __ flush();
101 s->set_exception_points(npe_addr, ame_addr);
102 return s;
103 }
104
105
106 VtableStub* VtableStubs::create_itable_stub(int vtable_index) {
107 // Note well: pd_code_size_limit is the absolute minimum we can get
108 // away with. If you add code here, bump the code stub size
109 // returned by pd_code_size_limit!
110 const int amd64_code_length = VtableStub::pd_code_size_limit(false);
111 VtableStub* s = new(amd64_code_length) VtableStub(false, vtable_index);
112 ResourceMark rm;
113 CodeBuffer cb(s->entry_point(), amd64_code_length);
114 MacroAssembler* masm = new MacroAssembler(&cb);
115
116 #ifndef PRODUCT
117 if (CountCompiledCalls) {
118 __ incrementl(ExternalAddress((address) SharedRuntime::nof_megamorphic_calls_addr()));
119 }
120 #endif
121
122 // Entry arguments:
123 // rax: Interface
124 // j_rarg0: Receiver
125
126 // Free registers (non-args) are rax (interface), rbx
127
128 // get receiver (need to skip return address on top of stack)
129
130 assert(VtableStub::receiver_location() == j_rarg0->as_VMReg(), "receiver expected in j_rarg0");
131 // get receiver klass (also an implicit null-check)
132 address npe_addr = __ pc();
133
134 __ load_klass(rbx, j_rarg0);
135
136 // If we take a trap while this arg is on the stack we will not
137 // be able to walk the stack properly. This is not an issue except
138 // when there are mistakes in this assembly code that could generate
139 // a spurious fault. Ask me how I know...
140
141 __ push(j_rarg1); // Most registers are in use, so save one
142
143 // compute itable entry offset (in words)
144 const int base = instanceKlass::vtable_start_offset() * wordSize;
145 assert(vtableEntry::size() * wordSize == 8,
146 "adjust the scaling in the code below");
147 // Get length of vtable
148 __ movl(j_rarg1,
149 Address(rbx, instanceKlass::vtable_length_offset() * wordSize));
150 __ lea(rbx, Address(rbx, j_rarg1, Address::times_8, base));
151
152 if (HeapWordsPerLong > 1) {
153 // Round up to align_object_offset boundary
154 __ round_to(rbx, BytesPerLong);
155 }
156 Label hit, next, entry, throw_icce;
157
158 __ jmpb(entry);
159
160 __ bind(next);
161 __ addptr(rbx, itableOffsetEntry::size() * wordSize);
162
163 __ bind(entry);
164
165 // If the entry is NULL then we've reached the end of the table
166 // without finding the expected interface, so throw an exception
167 __ movptr(j_rarg1, Address(rbx, itableOffsetEntry::interface_offset_in_bytes()));
168 __ testptr(j_rarg1, j_rarg1);
169 __ jcc(Assembler::zero, throw_icce);
170 __ cmpptr(rax, j_rarg1);
171 __ jccb(Assembler::notEqual, next);
172
173 // We found a hit, move offset into j_rarg1
174 __ movl(j_rarg1, Address(rbx, itableOffsetEntry::offset_offset_in_bytes()));
175
176 // Compute itableMethodEntry
177 const int method_offset =
178 (itableMethodEntry::size() * wordSize * vtable_index) +
179 itableMethodEntry::method_offset_in_bytes();
180
181 // Get methodOop and entrypoint for compiler
182
183 // Get klass pointer again
184 __ load_klass(rax, j_rarg0);
185
186 const Register method = rbx;
187 __ movptr(method, Address(rax, j_rarg1, Address::times_1, method_offset));
188
189 // Restore saved register, before possible trap.
190 __ pop(j_rarg1);
191
192 // method (rbx): methodOop
193 // j_rarg0: receiver
194
195
196 #ifdef ASSERT
197 if (DebugVtables) {
198 Label L2;
199 __ cmpptr(method, (int32_t)NULL_WORD);
200 __ jcc(Assembler::equal, L2);
201 __ cmpptr(Address(method, methodOopDesc::from_compiled_offset()), (int32_t)NULL_WORD);
202 __ jcc(Assembler::notZero, L2);
203 __ stop("compiler entrypoint is null");
204 __ bind(L2);
205 }
206 #endif // ASSERT
207
208 // rbx: methodOop
209 // j_rarg0: receiver
210 address ame_addr = __ pc();
211 __ jmp(Address(method, methodOopDesc::from_compiled_offset()));
212
213 __ bind(throw_icce);
214 // Restore saved register
215 __ pop(j_rarg1);
216 __ jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
217
218 __ flush();
219
220 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
221
222 s->set_exception_points(npe_addr, ame_addr);
223 return s;
224 }
225
226 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
227 if (is_vtable_stub) {
228 // Vtable stub size
229 return (DebugVtables ? 512 : 24) + (CountCompiledCalls ? 13 : 0) +
230 (UseCompressedOops ? 16 : 0); // 1 leaq can be 3 bytes + 1 long
231 } else {
232 // Itable stub size
233 return (DebugVtables ? 636 : 72) + (CountCompiledCalls ? 13 : 0) +
234 (UseCompressedOops ? 32 : 0); // 2 leaqs
235 }
236 }
237
238 int VtableStub::pd_code_alignment() {
239 return wordSize;
240 }