1 /*
2 * Copyright (c) 1997, 2018, 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/compiledICHolder.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 #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 VtableStub* VtableStubs::create_vtable_stub(int vtable_index) {
51 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
52 const int stub_code_length = code_size_limit(true);
53 VtableStub* s = new(stub_code_length) VtableStub(true, vtable_index);
54 // Can be NULL if there is no free space in the code cache.
55 if (s == NULL) {
56 return NULL;
57 }
58
59 // Count unused bytes in instruction sequences of variable size.
60 // We add them to the computed buffer size in order to avoid
61 // overflow in subsequently generated stubs.
62 address start_pc;
63 int slop_bytes = 0;
64 int slop_delta = 0;
65 const int index_dependent_slop = ((vtable_index < 512) ? 2 : 0)*BytesPerInstWord; // code size change with transition from 13-bit to 32-bit constant (@index == 512?).
66
67 ResourceMark rm;
68 CodeBuffer cb(s->entry_point(), stub_code_length);
69 MacroAssembler* masm = new MacroAssembler(&cb);
70
71 #if (!defined(PRODUCT) && defined(COMPILER2))
72 if (CountCompiledCalls) {
73 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), G5, G3_scratch);
74 }
75 #endif // PRODUCT
76
77 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
78
79 // get receiver klass
80 address npe_addr = __ pc();
81 __ load_klass(O0, G3_scratch);
82
83 #ifndef PRODUCT
84 if (DebugVtables) {
85 Label L;
86 // check offset vs vtable length
87 __ ld(G3_scratch, in_bytes(Klass::vtable_length_offset()), G5);
88 __ cmp_and_br_short(G5, vtable_index*vtableEntry::size(), Assembler::greaterUnsigned, Assembler::pt, L);
89
90 // set generates 8 instructions (worst case), 1 instruction (best case)
91 start_pc = __ pc();
92 __ set(vtable_index, O2);
93 slop_delta = __ worst_case_insts_for_set()*BytesPerInstWord - (__ pc() - start_pc);
94 slop_bytes += slop_delta;
95 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta);
96
97 // there is no variance in call_VM() emitted code.
98 __ call_VM(noreg, CAST_FROM_FN_PTR(address, bad_compiled_vtable_index), O0, O2);
99 __ bind(L);
100 }
101 #endif
102
103 // set Method* (in case of interpreted method), and destination address
104 start_pc = __ pc();
105 __ lookup_virtual_method(G3_scratch, vtable_index, G5_method);
106 // lookup_virtual_method generates 3 instructions (worst case), 1 instruction (best case)
107 slop_delta = 3*BytesPerInstWord - (int)(__ pc() - start_pc);
108 slop_bytes += slop_delta;
109 assert(slop_delta >= 0, "negative slop(%d) encountered, adjust code size estimate!", slop_delta);
110
111 #ifndef PRODUCT
112 if (DebugVtables) {
113 Label L;
114 __ br_notnull_short(G5_method, Assembler::pt, L);
115 __ stop("Vtable entry is ZERO");
116 __ bind(L);
117 }
118 #endif
119
120 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
121 // NOTE: for vtable dispatches, the vtable entry will never be null.
122
123 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
124
125 // jump to target (either compiled code or c2iadapter)
126 __ JMP(G3_scratch, 0);
127 // load Method* (in case we call c2iadapter)
128 __ delayed()->nop();
129
130 masm->flush();
131 slop_bytes += index_dependent_slop; // add'l slop for size variance due to large itable offsets
132 bookkeeping(masm, tty, s, npe_addr, ame_addr, true, vtable_index, slop_bytes, index_dependent_slop);
133
134 return s;
135 }
136
137
138 VtableStub* VtableStubs::create_itable_stub(int itable_index) {
139 // Read "A word on VtableStub sizing" in share/code/vtableStubs.hpp for details on stub sizing.
140 const int stub_code_length = code_size_limit(false);
141 VtableStub* s = new(stub_code_length) VtableStub(false, itable_index);
142 // Can be NULL if there is no free space in the code cache.
143 if (s == NULL) {
144 return NULL;
145 }
146 // Count unused bytes in instruction sequences of variable size.
147 // We add them to the computed buffer size in order to avoid
148 // overflow in subsequently generated stubs.
149 address start_pc;
150 int slop_bytes = 0;
151 int slop_delta = 0;
152 const int index_dependent_slop = ((itable_index < 512) ? 2 : 0)*BytesPerInstWord; // code size change with transition from 13-bit to 32-bit constant (@index == 512?).
153
154 ResourceMark rm;
155 CodeBuffer cb(s->entry_point(), stub_code_length);
156 MacroAssembler* masm = new MacroAssembler(&cb);
157
158 #if (!defined(PRODUCT) && defined(COMPILER2))
159 if (CountCompiledCalls) {
160 // Use G3_scratch, G4_scratch as work regs for inc_counter.
161 // These are defined before use further down.
162 __ inc_counter(SharedRuntime::nof_megamorphic_calls_addr(), G3_scratch, G4_scratch);
163 }
164 #endif // PRODUCT
165
166 Register G3_Klass = G3_scratch;
167 Register G5_icholder = G5; // Passed in as an argument
168 Register G4_interface = G4_scratch;
169 Label search;
170
171 // Entry arguments:
172 // G5_interface: Interface
173 // O0: Receiver
174 assert(VtableStub::receiver_location() == O0->as_VMReg(), "receiver expected in O0");
175
176 // get receiver klass (also an implicit null-check)
177 address npe_addr = __ pc();
178 __ load_klass(O0, G3_Klass);
179
180 // Push a new window to get some temp registers. This chops the head of all
181 // my 64-bit %o registers in the LION build, but this is OK because no longs
182 // are passed in the %o registers. Instead, longs are passed in G1 and G4
183 // and so those registers are not available here.
184 __ save(SP,-frame::register_save_words*wordSize,SP);
185
186 Label L_no_such_interface;
187 Register L5_method = L5;
188
189 start_pc = __ pc();
190
191 // Receiver subtype check against REFC.
192 __ ld_ptr(G5_icholder, CompiledICHolder::holder_klass_offset(), G4_interface);
193 __ lookup_interface_method(// inputs: rec. class, interface, itable index
194 G3_Klass, G4_interface, itable_index,
195 // outputs: scan temp. reg1, scan temp. reg2
196 L5_method, L2, L3,
197 L_no_such_interface,
198 /*return_method=*/ false);
199
200 const ptrdiff_t typecheckSize = __ pc() - start_pc;
201 start_pc = __ pc();
202
203 // Get Method* and entrypoint for compiler
204 __ ld_ptr(G5_icholder, CompiledICHolder::holder_metadata_offset(), G4_interface);
205 __ lookup_interface_method(// inputs: rec. class, interface, itable index
206 G3_Klass, G4_interface, itable_index,
207 // outputs: method, scan temp. reg
208 L5_method, L2, L3,
209 L_no_such_interface);
210
211 const ptrdiff_t lookupSize = __ pc() - start_pc;
212
213 // Reduce "estimate" such that "padding" does not drop below 8.
214 // Do not target a left-over number of zero, because a very
215 // large vtable or itable offset (> 4K) will require an extra
216 // sethi/or pair of instructions.
217 // Found typecheck(60) + lookup(72) to exceed previous extimate (32*4).
218 const ptrdiff_t estimate = 36*BytesPerInstWord;
219 const ptrdiff_t codesize = typecheckSize + lookupSize + index_dependent_slop;
220 slop_delta = (int)(estimate - codesize);
221 slop_bytes += slop_delta;
222 assert(slop_delta >= 0, "itable #%d: Code size estimate (%d) for lookup_interface_method too small, required: %d", itable_index, (int)estimate, (int)codesize);
223
224 #ifndef PRODUCT
225 if (DebugVtables) {
226 Label L01;
227 __ br_notnull_short(L5_method, Assembler::pt, L01);
228 __ stop("Method* is null");
229 __ bind(L01);
230 }
231 #endif
232
233 // If the following load is through a NULL pointer, we'll take an OS
234 // exception that should translate into an AbstractMethodError. We need the
235 // window count to be correct at that time.
236 __ restore(L5_method, 0, G5_method);
237 // Restore registers *before* the AME point.
238
239 address ame_addr = __ pc(); // if the vtable entry is null, the method is abstract
240 __ ld_ptr(G5_method, in_bytes(Method::from_compiled_offset()), G3_scratch);
241
242 // G5_method: Method*
243 // O0: Receiver
244 // G3_scratch: entry point
245 __ JMP(G3_scratch, 0);
246 __ delayed()->nop();
247
248 __ bind(L_no_such_interface);
249 // Handle IncompatibleClassChangeError in itable stubs.
250 // More detailed error message.
251 // We force resolving of the call site by jumping to the "handle
252 // wrong method" stub, and so let the interpreter runtime do all the
253 // dirty work.
254 AddressLiteral icce(SharedRuntime::get_handle_wrong_method_stub());
255 __ jump_to(icce, G3_scratch);
256 __ delayed()->restore();
257
258 masm->flush();
259 slop_bytes += index_dependent_slop; // add'l slop for size variance due to large itable offsets
260 bookkeeping(masm, tty, s, npe_addr, ame_addr, false, itable_index, slop_bytes, index_dependent_slop);
261
262 return s;
263 }
264
265 int VtableStub::pd_code_alignment() {
266 // UltraSPARC cache line size is 8 instructions:
267 const unsigned int icache_line_size = 32;
268 return icache_line_size;
269 }