1 /*
2 * Copyright (c) 1997, 2012, Oracle and/or its affiliates. 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 *
23 */
24
25 #include "precompiled.hpp"
26 #include "asm/assembler.hpp"
27 #include "assembler_sparc.inline.hpp"
28 #include "code/vtableStubs.hpp"
29 #include "interp_masm_sparc.hpp"
30 #include "memory/resourceArea.hpp"
31 #include "oops/instanceKlass.hpp"
32 #include "oops/klassVtable.hpp"
33 #include "runtime/sharedRuntime.hpp"
34 #include "vmreg_sparc.inline.hpp"
35 #ifdef COMPILER2
36 #include "opto/runtime.hpp"
37 #endif
38
39 // machine-dependent part of VtableStubs: create vtableStub of correct size and
40 // initialize its code
41
42 #define __ masm->
43
44
45 #ifndef PRODUCT
46 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oopDesc* receiver, int index);
47 #endif
48
49
50 // Used by compiler only; may use only caller saved, non-argument registers
51 // NOTE: %%%% if any change is made to this stub make sure that the function
52 // pd_code_size_limit is changed to ensure the correct size for VtableStub
53 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
54 const int sparc_code_length = VtableStub::pd_code_size_limit(true);
55 VtableStub* s = new(sparc_code_length) VtableStub(true, vtable_index);
56 ResourceMark rm;
57 CodeBuffer cb(s->entry_point(), sparc_code_length);
58 MacroAssembler* masm = new MacroAssembler(&cb);
59
60 #ifndef PRODUCT
61 if (CountCompiledCalls) {
62 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), G5, G3_scratch);
63 }
64 #endif /* PRODUCT */
65
66 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
67
68 // get receiver klass
69 address npe_addr = __ pc();
70 __ load_klass(O0, G3_scratch);
71
72 // set Method* (in case of interpreted method), and destination address
73 #ifndef PRODUCT
74 if (DebugVtables) {
75 Label L;
76 // check offset vs vtable length
77 __ ld(G3_scratch, InstanceKlass::vtable_length_offset()*wordSize, G5);
78 __ cmp_and_br_short(G5, vtable_index*vtableEntry::size(), Assembler::greaterUnsigned, Assembler::pt, L);
79 __ set(vtable_index, O2);
80 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), O0, O2);
81 __ bind(L);
82 }
83 #endif
84
85 __ lookup_virtual_method(G3_scratch, vtable_index, G5_method);
86
87 #ifndef PRODUCT
88 if (DebugVtables) {
89 Label L;
90 __ br_notnull_short(G5_method, Assembler::pt, L);
91 __ stop("Vtable entry is ZERO");
92 __ bind(L);
93 }
94 #endif
95
96 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
97 // NOTE: for vtable dispatches, the vtable entry will never be null.
98
99 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
100
101 // jump to target (either compiled code or c2iadapter)
102 __ JMP(G3_scratch, 0);
103 // load Method* (in case we call c2iadapter)
104 __ delayed()->nop();
105
106 masm->flush();
107
108 if (PrintMiscellaneous && (WizardMode || Verbose)) {
109 tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",
110 vtable_index, 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 // shut the door on sizing bugs
116 int slop = 2*BytesPerInstWord; // 32-bit offset is this much larger than a 13-bit one
117 assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for sethi;add");
118
119 s->set_exception_points(npe_addr, ame_addr);
120 return s;
121 }
122
123
124 // NOTE: %%%% if any change is made to this stub make sure that the function
125 // pd_code_size_limit is changed to ensure the correct size for VtableStub
126 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
127 const int sparc_code_length = VtableStub::pd_code_size_limit(false);
128 VtableStub* s = new(sparc_code_length) VtableStub(false, itable_index);
129 ResourceMark rm;
130 CodeBuffer cb(s->entry_point(), sparc_code_length);
131 MacroAssembler* masm = new MacroAssembler(&cb);
132
133 Register G3_Klass = G3_scratch;
134 Register G5_interface = G5; // Passed in as an argument
135 Label search;
136
137 // Entry arguments:
138 // G5_interface: Interface
139 // O0: Receiver
140 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
141
142 // get receiver klass (also an implicit null-check)
143 address npe_addr = __ pc();
144 __ load_klass(O0, G3_Klass);
145
146 // Push a new window to get some temp registers. This chops the head of all
147 // my 64-bit %o registers in the LION build, but this is OK because no longs
148 // are passed in the %o registers. Instead, longs are passed in G1 and G4
149 // and so those registers are not available here.
150 __ save(SP,-frame::register_save_words*wordSize,SP);
151
152 #ifndef PRODUCT
153 if (CountCompiledCalls) {
154 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), L0, L1);
155 }
156 #endif /* PRODUCT */
157
158 Label throw_icce;
159
160 Register L5_method = L5;
161 __ lookup_interface_method(// inputs: rec. class, interface, itable index
162 G3_Klass, G5_interface, itable_index,
163 // outputs: method, scan temp. reg
164 L5_method, L2, L3,
165 throw_icce);
166
167 #ifndef PRODUCT
168 if (DebugVtables) {
169 Label L01;
170 __ br_notnull_short(L5_method, Assembler::pt, L01);
171 __ stop("Method* is null");
172 __ bind(L01);
173 }
174 #endif
175
176 // If the following load is through a NULL pointer, we'll take an OS
177 // exception that should translate into an AbstractMethodError. We need the
178 // window count to be correct at that time.
179 __ restore(L5_method, 0, G5_method);
180 // Restore registers *before* the AME point.
181
182 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
183 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
184
185 // G5_method: Method*
186 // O0: Receiver
187 // G3_scratch: entry point
188 __ JMP(G3_scratch, 0);
189 __ delayed()->nop();
190
191 __ bind(throw_icce);
192 AddressLiteral icce(StubRoutines::throw_IncompatibleClassChangeError_entry());
193 __ jump_to(icce, G3_scratch);
194 __ delayed()->restore();
195
196 masm->flush();
197
198 if (PrintMiscellaneous && (WizardMode || Verbose)) {
199 tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",
200 itable_index, s->entry_point(),
201 (int)(s->code_end() - s->entry_point()),
202 (int)(s->code_end() - __ pc()));
203 }
204 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
205 // shut the door on sizing bugs
206 int slop = 2*BytesPerInstWord; // 32-bit offset is this much larger than a 13-bit one
207 assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for sethi;add");
208
209 s->set_exception_points(npe_addr, ame_addr);
210 return s;
211 }
212
213
214 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
215 if (TraceJumps || DebugVtables || CountCompiledCalls || VerifyOops) return 1000;
216 else {
217 const int slop = 2*BytesPerInstWord; // sethi;add (needed for long offsets)
218 if (is_vtable_stub) {
219 // ld;ld;ld,jmp,nop
220 const int basic = 5*BytesPerInstWord +
221 // shift;add for load_klass (only shift with zero heap based)
222 (UseCompressedKlassPointers ?
223 ((Universe::narrow_oop_base() == NULL) ? BytesPerInstWord : 2*BytesPerInstWord) : 0);
224 return basic + slop;
225 } else {
226 const int basic = (28 LP64_ONLY(+ 6)) * BytesPerInstWord +
227 // shift;add for load_klass (only shift with zero heap based)
228 (UseCompressedKlassPointers ?
229 ((Universe::narrow_oop_base() == NULL) ? BytesPerInstWord : 2*BytesPerInstWord) : 0);
230 return (basic + slop);
231 }
232 }
233
234 // In order to tune these parameters, run the JVM with VM options
235 // +PrintMiscellaneous and +WizardMode to see information about
236 // actual itable stubs. Look for lines like this:
237 // itable #1 at 0x5551212[116] left over: 8
238 // Reduce the constants so that the "left over" number is 8
239 // Do not aim at a left-over number of zero, because a very
240 // large vtable or itable offset (> 4K) will require an extra
241 // sethi/or pair of instructions.
242 //
243 // The JVM98 app. _202_jess has a megamorphic interface call.
244 // The itable code looks like this:
245 // Decoding VtableStub itbl[1]@16
246 // ld [ %o0 + 4 ], %g3
247 // save %sp, -64, %sp
248 // ld [ %g3 + 0xe8 ], %l2
249 // sll %l2, 2, %l2
250 // add %l2, 0x134, %l2
251 // and %l2, -8, %l2 ! NOT_LP64 only
252 // add %g3, %l2, %l2
253 // add %g3, 4, %g3
254 // ld [ %l2 ], %l5
255 // brz,pn %l5, throw_icce
256 // cmp %l5, %g5
257 // be %icc, success
258 // add %l2, 8, %l2
259 // loop:
260 // ld [ %l2 ], %l5
261 // brz,pn %l5, throw_icce
262 // cmp %l5, %g5
263 // bne,pn %icc, loop
264 // add %l2, 8, %l2
265 // success:
266 // ld [ %l2 + -4 ], %l2
267 // ld [ %g3 + %l2 ], %l5
268 // restore %l5, 0, %g5
269 // ld [ %g5 + 0x44 ], %g3
270 // jmp %g3
271 // nop
272 // throw_icce:
273 // sethi %hi(throw_ICCE_entry), %g3
274 // ! 5 more instructions here, LP64_ONLY
275 // jmp %g3 + %lo(throw_ICCE_entry)
276 // restore
277 }
278
279
280 int VtableStub::pd_code_alignment() {
281 // UltraSPARC cache line size is 8 instructions:
282 const unsigned int icache_line_size = 32;
283 return icache_line_size;
284 }