1 /*
2 * Copyright (c) 1997, 2013, 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/macroAssembler.inline.hpp"
27 #include "code/vtableStubs.hpp"
28 #include "interp_masm_sparc.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "oops/instanceKlass.hpp"
31 #include "oops/klassVtable.hpp"
32 #include "runtime/sharedRuntime.hpp"
33 #include "vmreg_sparc.inline.hpp"
34 #ifdef COMPILER2
35 #include "opto/runtime.hpp"
36 #endif
37
38 // machine-dependent part of VtableStubs: create vtableStub of correct size and
39 // initialize its code
40
41 #define __ masm->
42
43
44 #ifndef PRODUCT
45 extern "C" void bad_compiled_vtable_index(JavaThread* thread, oopDesc* receiver, int index);
46 #endif
47
48
49 // Used by compiler only; may use only caller saved, non-argument registers
50 // NOTE: %%%% if any change is made to this stub make sure that the function
51 // pd_code_size_limit is changed to ensure the correct size for VtableStub
52 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
53 const int sparc_code_length = VtableStub::pd_code_size_limit(true);
54 VtableStub* s = new(sparc_code_length) VtableStub(true, vtable_index);
55 ResourceMark rm;
56 CodeBuffer cb(s->entry_point(), sparc_code_length);
57 MacroAssembler* masm = new MacroAssembler(&cb);
58
59 #ifndef PRODUCT
60 if (CountCompiledCalls) {
61 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), G5, G3_scratch);
62 }
63 #endif /* PRODUCT */
64
65 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
66
67 // get receiver klass
68 address npe_addr = __ pc();
69 __ load_klass(O0, G3_scratch);
70
71 // set Method* (in case of interpreted method), and destination address
72 #ifndef PRODUCT
73 if (DebugVtables) {
74 Label L;
75 // check offset vs vtable length
76 __ ld(G3_scratch, InstanceKlass::vtable_length_offset()*wordSize, G5);
77 __ cmp_and_br_short(G5, vtable_index*vtableEntry::size(), Assembler::greaterUnsigned, Assembler::pt, L);
78 __ set(vtable_index, O2);
79 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), O0, O2);
80 __ bind(L);
81 }
82 #endif
83
84 __ lookup_virtual_method(G3_scratch, vtable_index, G5_method);
85
86 #ifndef PRODUCT
87 if (DebugVtables) {
88 Label L;
89 __ br_notnull_short(G5_method, Assembler::pt, L);
90 __ stop("Vtable entry is ZERO");
91 __ bind(L);
92 }
93 #endif
94
95 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
96 // NOTE: for vtable dispatches, the vtable entry will never be null.
97
98 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
99
100 // jump to target (either compiled code or c2iadapter)
101 __ JMP(G3_scratch, 0);
102 // load Method* (in case we call c2iadapter)
103 __ delayed()->nop();
104
105 masm->flush();
106
107 if (PrintMiscellaneous && (WizardMode || Verbose)) {
108 tty->print_cr("vtable #%d at "PTR_FORMAT"[%d] left over: %d",
109 vtable_index, s->entry_point(),
110 (int)(s->code_end() - s->entry_point()),
111 (int)(s->code_end() - __ pc()));
112 }
113 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
114 // shut the door on sizing bugs
115 int slop = 2*BytesPerInstWord; // 32-bit offset is this much larger than a 13-bit one
116 assert(vtable_index > 10 || __ pc() + slop <= s->code_end(), "room for sethi;add");
117
118 s->set_exception_points(npe_addr, ame_addr);
119 return s;
120 }
121
122
123 // NOTE: %%%% if any change is made to this stub make sure that the function
124 // pd_code_size_limit is changed to ensure the correct size for VtableStub
125 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
126 const int sparc_code_length = VtableStub::pd_code_size_limit(false);
127 VtableStub* s = new(sparc_code_length) VtableStub(false, itable_index);
128 ResourceMark rm;
129 CodeBuffer cb(s->entry_point(), sparc_code_length);
130 MacroAssembler* masm = new MacroAssembler(&cb);
131
132 Register G3_Klass = G3_scratch;
133 Register G5_interface = G5; // Passed in as an argument
134 Label search;
135
136 // Entry arguments:
137 // G5_interface: Interface
138 // O0: Receiver
139 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
140
141 // get receiver klass (also an implicit null-check)
142 address npe_addr = __ pc();
143 __ load_klass(O0, G3_Klass);
144
145 // Push a new window to get some temp registers. This chops the head of all
146 // my 64-bit %o registers in the LION build, but this is OK because no longs
147 // are passed in the %o registers. Instead, longs are passed in G1 and G4
148 // and so those registers are not available here.
149 __ save(SP,-frame::register_save_words*wordSize,SP);
150
151 #ifndef PRODUCT
152 if (CountCompiledCalls) {
153 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), L0, L1);
154 }
155 #endif /* PRODUCT */
156
157 Label throw_icce;
158
159 Register L5_method = L5;
160 __ lookup_interface_method(// inputs: rec. class, interface, itable index
161 G3_Klass, G5_interface, itable_index,
162 // outputs: method, scan temp. reg
163 L5_method, L2, L3,
164 throw_icce);
165
166 #ifndef PRODUCT
167 if (DebugVtables) {
168 Label L01;
169 __ br_notnull_short(L5_method, Assembler::pt, L01);
170 __ stop("Method* is null");
171 __ bind(L01);
172 }
173 #endif
174
175 // If the following load is through a NULL pointer, we'll take an OS
176 // exception that should translate into an AbstractMethodError. We need the
177 // window count to be correct at that time.
178 __ restore(L5_method, 0, G5_method);
179 // Restore registers *before* the AME point.
180
181 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
182 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
183
184 // G5_method: Method*
185 // O0: Receiver
186 // G3_scratch: entry point
187 __ JMP(G3_scratch, 0);
188 __ delayed()->nop();
189
190 __ bind(throw_icce);
191 AddressLiteral icce(StubRoutines::throw_IncompatibleClassChangeError_entry());
192 __ jump_to(icce, G3_scratch);
193 __ delayed()->restore();
194
195 masm->flush();
196
197 if (PrintMiscellaneous && (WizardMode || Verbose)) {
198 tty->print_cr("itable #%d at "PTR_FORMAT"[%d] left over: %d",
199 itable_index, s->entry_point(),
200 (int)(s->code_end() - s->entry_point()),
201 (int)(s->code_end() - __ pc()));
202 }
203 guarantee(__ pc() <= s->code_end(), "overflowed buffer");
204 // shut the door on sizing bugs
205 int slop = 2*BytesPerInstWord; // 32-bit offset is this much larger than a 13-bit one
206 assert(itable_index > 10 || __ pc() + slop <= s->code_end(), "room for sethi;add");
207
208 s->set_exception_points(npe_addr, ame_addr);
209 return s;
210 }
211
212
213 int VtableStub::pd_code_size_limit(bool is_vtable_stub) {
214 if (TraceJumps || DebugVtables || CountCompiledCalls || VerifyOops) return 1000;
215 else {
216 const int slop = 2*BytesPerInstWord; // sethi;add (needed for long offsets)
217 if (is_vtable_stub) {
218 // ld;ld;ld,jmp,nop
219 const int basic = 5*BytesPerInstWord +
220 // shift;add for load_klass (only shift with zero heap based)
221 (UseCompressedClassPointers ?
222 MacroAssembler::instr_size_for_decode_klass_not_null() : 0);
223 return basic + slop;
224 } else {
225 const int basic = (28 LP64_ONLY(+ 6)) * BytesPerInstWord +
226 // shift;add for load_klass (only shift with zero heap based)
227 (UseCompressedClassPointers ?
228 MacroAssembler::instr_size_for_decode_klass_not_null() : 0);
229 return (basic + slop);
230 }
231 }
232
233 // In order to tune these parameters, run the JVM with VM options
234 // +PrintMiscellaneous and +WizardMode to see information about
235 // actual itable stubs. Look for lines like this:
236 // itable #1 at 0x5551212[116] left over: 8
237 // Reduce the constants so that the "left over" number is 8
238 // Do not aim at a left-over number of zero, because a very
239 // large vtable or itable offset (> 4K) will require an extra
240 // sethi/or pair of instructions.
241 //
242 // The JVM98 app. _202_jess has a megamorphic interface call.
243 // The itable code looks like this:
244 // Decoding VtableStub itbl[1]@16
245 // ld [ %o0 + 4 ], %g3
246 // save %sp, -64, %sp
247 // ld [ %g3 + 0xe8 ], %l2
248 // sll %l2, 2, %l2
249 // add %l2, 0x134, %l2
250 // and %l2, -8, %l2 ! NOT_LP64 only
251 // add %g3, %l2, %l2
252 // add %g3, 4, %g3
253 // ld [ %l2 ], %l5
254 // brz,pn %l5, throw_icce
255 // cmp %l5, %g5
256 // be %icc, success
257 // add %l2, 8, %l2
258 // loop:
259 // ld [ %l2 ], %l5
260 // brz,pn %l5, throw_icce
261 // cmp %l5, %g5
262 // bne,pn %icc, loop
263 // add %l2, 8, %l2
264 // success:
265 // ld [ %l2 + -4 ], %l2
266 // ld [ %g3 + %l2 ], %l5
267 // restore %l5, 0, %g5
268 // ld [ %g5 + 0x44 ], %g3
269 // jmp %g3
270 // nop
271 // throw_icce:
272 // sethi %hi(throw_ICCE_entry), %g3
273 // ! 5 more instructions here, LP64_ONLY
274 // jmp %g3 + %lo(throw_ICCE_entry)
275 // restore
276 }
277
278
279 int VtableStub::pd_code_alignment() {
280 // UltraSPARC cache line size is 8 instructions:
281 const unsigned int icache_line_size = 32;
282 return icache_line_size;
283 }