1 /*
2 * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * Copyright (c) 2015, Linaro Ltd. All rights reserved.
5 * Copyright (c) 2015-2018, Azul Systems, Inc. All rights reserved.
6 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
7 *
8 * This code is free software; you can redistribute it and/or modify it
9 * under the terms of the GNU General Public License version 2 only, as
10 * published by the Free Software Foundation.
11 *
12 * This code is distributed in the hope that it will be useful, but WITHOUT
13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 * version 2 for more details (a copy is included in the LICENSE file that
16 * accompanied this code).
17 *
18 * You should have received a copy of the GNU General Public License version
19 * 2 along with this work; if not, write to the Free Software Foundation,
20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
21 *
22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
23 * or visit www.oracle.com if you need additional information or have any
24 * questions.
25 *
26 */
27
28 #include "precompiled.hpp"
29 #include "asm/macroAssembler.hpp"
30 #include "classfile/javaClasses.inline.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "interpreter/interpreterRuntime.hpp"
33 #include "memory/allocation.inline.hpp"
34 #include "prims/methodHandles.hpp"
35 #include "runtime/flags/flagSetting.hpp"
36 #include "runtime/frame.inline.hpp"
37
38 #define __ _masm->
39
40 #ifdef PRODUCT
41 #define BLOCK_COMMENT(str) /* nothing */
42 #else
43 #define BLOCK_COMMENT(str) __ block_comment(str)
44 #endif
45
46 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
47
48 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
49 if (VerifyMethodHandles)
50 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
51 "MH argument is a Class");
52 __ ldr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
53 }
54
55 #ifdef ASSERT
56 static int check_nonzero(const char* xname, int x) {
57 assert(x != 0, "%s should be nonzero", xname);
58 return x;
59 }
60 #define NONZERO(x) check_nonzero(#x, x)
61 #else //ASSERT
62 #define NONZERO(x) (x)
63 #endif //PRODUCT
64
65 #ifdef ASSERT
66 void MethodHandles::verify_klass(MacroAssembler* _masm,
67 Register obj, SystemDictionary::WKID klass_id,
68 const char* error_message) {
69 // FIXME Did this code ever work?
70 // or have I changed the working of cmpptr?
71 // previously cmpptr took the klass_addr, did it also do dereference before the comparison?
72 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
73 Klass* klass = SystemDictionary::well_known_klass(klass_id);
74 Register temp = rscratch2;
75 Register temp2 = rscratch1; // used by MacroAssembler::cmpptr
76 Label L_ok, L_bad;
77 BLOCK_COMMENT("verify_klass {");
78 __ verify_oop(obj);
79 __ cbz(obj, L_bad);
80 __ push(RegSet::of(temp, temp2), sp);
81 __ load_klass(temp, obj);
82 __ cmpptr(temp, ExternalAddress((address) klass_addr));
83 __ b(L_ok, Assembler::EQ);
84 intptr_t super_check_offset = klass->super_check_offset();
85 __ ldr(temp, Address(temp, super_check_offset));
86 __ cmpptr(temp, ExternalAddress((address) klass_addr));
87 __ b(L_ok, Assembler::EQ);
88 __ pop(RegSet::of(temp, temp2), sp);
89 __ bind(L_bad);
90 __ stop(error_message);
91 __ BIND(L_ok);
92 __ pop(RegSet::of(temp, temp2), sp);
93 BLOCK_COMMENT("} verify_klass");
94 }
95
96 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { }
97
98 #endif //ASSERT
99
100 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
101 bool for_compiler_entry) {
102 assert(method == rmethod, "interpreter calling convention");
103 Label L_no_such_method;
104 __ cbz(rmethod, L_no_such_method);
105 __ verify_method_ptr(method);
106
107 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
108 Label run_compiled_code;
109 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
110 // compiled code in threads for which the event is enabled. Check here for
111 // interp_only_mode if these events CAN be enabled.
112
113 __ ldrb(rscratch1, Address(rthread, JavaThread::interp_only_mode_offset()));
114 __ cbnz(rscratch1, run_compiled_code);
115 __ ldr(rscratch1, Address(method, Method::interpreter_entry_offset()));
116 __ b(rscratch1);
117 __ BIND(run_compiled_code);
118 }
119
120 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
121 Method::from_interpreted_offset();
122 __ ldr(rscratch1,Address(method, entry_offset));
123 __ b(rscratch1);
124 __ bind(L_no_such_method);
125 __ far_jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
126 }
127
128 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
129 Register recv, Register method_temp,
130 Register temp2,
131 bool for_compiler_entry) {
132 BLOCK_COMMENT("jump_to_lambda_form {");
133 // This is the initial entry point of a lazy method handle.
134 // After type checking, it picks up the invoker from the LambdaForm.
135 assert_different_registers(recv, method_temp, temp2);
136 assert(recv != noreg, "required register");
137 assert(method_temp == rmethod, "required register for loading method");
138
139 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
140
141 // Load the invoker, as MH -> MH.form -> LF.vmentry
142 __ verify_oop(recv);
143 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())), temp2);
144 __ verify_oop(method_temp);
145 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())), temp2);
146 __ verify_oop(method_temp);
147 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())), temp2);
148 __ verify_oop(method_temp);
149 __ access_load_word_at(T_ADDRESS, IN_HEAP, method_temp, Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())), noreg, noreg);
150
151 if (VerifyMethodHandles && !for_compiler_entry) {
152 // make sure recv is already on stack
153 __ ldr(temp2, Address(method_temp, Method::const_offset()));
154 __ load_sized_value(temp2,
155 Address(temp2, ConstMethod::size_of_parameters_offset()),
156 sizeof(u2), /*is_signed*/ false);
157 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
158 Label L;
159 __ ldr(rscratch1, __ argument_address(temp2, -1));
160 __ cmpoop(recv, rscratch1);
161 __ b(L, Assembler::EQ);
162 __ ldr(r0, __ argument_address(temp2, -1));
163 __ hlt(0);
164 __ BIND(L);
165 }
166
167 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
168 BLOCK_COMMENT("} jump_to_lambda_form");
169 }
170
171 // Code generation
172 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
173 vmIntrinsics::ID iid) {
174 const bool not_for_compiler_entry = false; // this is the interpreter entry
175 assert(is_signature_polymorphic(iid), "expected invoke iid");
176 if (iid == vmIntrinsics::_invokeGeneric ||
177 iid == vmIntrinsics::_compiledLambdaForm) {
178 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
179 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
180 // They all allow an appendix argument.
181 __ hlt(0); // empty stubs make SG sick
182 return NULL;
183 }
184
185 // rmethod: Method*
186 // r3: argument locator (parameter slot count, added to rsp)
187 // r1: used as temp to hold mh or receiver
188 // r0, r11: garbage temps, blown away
189 Register argp = r3; // argument list ptr, live on error paths
190 Register temp = r0;
191 Register mh = r1; // MH receiver; dies quickly and is recycled
192
193 // here's where control starts out:
194 __ align(CodeEntryAlignment);
195 address entry_point = __ pc();
196
197 if (VerifyMethodHandles) {
198 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
199 Label L;
200 BLOCK_COMMENT("verify_intrinsic_id {");
201 __ ldrh(rscratch1, Address(rmethod, Method::intrinsic_id_offset_in_bytes()));
202 __ cmp(rscratch1, (int) iid, temp);
203 __ b(L, Assembler::EQ);
204 if (iid == vmIntrinsics::_linkToVirtual ||
205 iid == vmIntrinsics::_linkToSpecial) {
206 // could do this for all kinds, but would explode assembly code size
207 trace_method_handle(_masm, "bad Method*::intrinsic_id");
208 }
209 __ hlt(0);
210 __ bind(L);
211 BLOCK_COMMENT("} verify_intrinsic_id");
212 }
213
214 // First task: Find out how big the argument list is.
215 Address r3_first_arg_addr;
216 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
217 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
218 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
219 __ ldr(argp, Address(rmethod, Method::const_offset()));
220 __ load_sized_value(argp,
221 Address(argp, ConstMethod::size_of_parameters_offset()),
222 sizeof(u2), /*is_signed*/ false);
223 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
224 r3_first_arg_addr = __ argument_address(argp, -1);
225 } else {
226 DEBUG_ONLY(argp = noreg);
227 }
228
229 if (!is_signature_polymorphic_static(iid)) {
230 __ ldr(mh, r3_first_arg_addr);
231 DEBUG_ONLY(argp = noreg);
232 }
233
234 // r3_first_arg_addr is live!
235
236 trace_method_handle_interpreter_entry(_masm, iid);
237 if (iid == vmIntrinsics::_invokeBasic) {
238 generate_method_handle_dispatch(_masm, iid, mh, noreg, not_for_compiler_entry);
239
240 } else {
241 // Adjust argument list by popping the trailing MemberName argument.
242 Register recv = noreg;
243 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
244 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
245 __ ldr(recv = r2, r3_first_arg_addr);
246 }
247 DEBUG_ONLY(argp = noreg);
248 Register rmember = rmethod; // MemberName ptr; incoming method ptr is dead now
249 __ pop(rmember); // extract last argument
250 generate_method_handle_dispatch(_masm, iid, recv, rmember, not_for_compiler_entry);
251 }
252
253 return entry_point;
254 }
255
256
257 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
258 vmIntrinsics::ID iid,
259 Register receiver_reg,
260 Register member_reg,
261 bool for_compiler_entry) {
262 assert(is_signature_polymorphic(iid), "expected invoke iid");
263 // temps used in this code are not used in *either* compiled or interpreted calling sequences
264 // use interpreter caching registers (caller-save in compiler).
265 // Starting from r5 as r4 used by gen_special_dispatch.
266 Register temp1 = r5;
267 Register temp2 = r6;
268 Register temp3 = r7;
269 assert_different_registers(temp1, temp2, temp3, receiver_reg, member_reg);
270 if (for_compiler_entry) {
271 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
272 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3);
273 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3);
274 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3);
275 }
276
277 assert_different_registers(temp1, temp2, temp3, receiver_reg);
278 assert_different_registers(temp1, temp2, temp3, member_reg);
279
280 if (iid == vmIntrinsics::_invokeBasic) {
281 // indirect through MH.form.vmentry.vmtarget
282 jump_to_lambda_form(_masm, receiver_reg, rmethod, temp1, for_compiler_entry);
283
284 } else {
285 // The method is a member invoker used by direct method handles.
286 if (VerifyMethodHandles) {
287 // make sure the trailing argument really is a MemberName (caller responsibility)
288 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),
289 "MemberName required for invokeVirtual etc.");
290 }
291
292 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
293 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
294 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()));
295 Address vmtarget_method( rmethod, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()));
296
297 Register temp1_recv_klass = temp1;
298 if (iid != vmIntrinsics::_linkToStatic) {
299 __ verify_oop(receiver_reg);
300 if (iid == vmIntrinsics::_linkToSpecial) {
301 // Don't actually load the klass; just null-check the receiver.
302 __ null_check(receiver_reg);
303 } else {
304 // load receiver klass itself
305 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
306 __ load_klass(temp1_recv_klass, receiver_reg);
307 __ verify_klass_ptr(temp1_recv_klass);
308 }
309 BLOCK_COMMENT("check_receiver {");
310 // The receiver for the MemberName must be in receiver_reg.
311 // Check the receiver against the MemberName.clazz
312 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
313 // Did not load it above...
314 __ load_klass(temp1_recv_klass, receiver_reg);
315 __ verify_klass_ptr(temp1_recv_klass);
316 }
317 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
318 Label L_ok;
319 Register temp2_defc = temp2;
320 __ load_heap_oop(temp2_defc, member_clazz, temp3);
321 load_klass_from_Class(_masm, temp2_defc);
322 __ verify_klass_ptr(temp2_defc);
323 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
324 // If we get here, the type check failed!
325 __ hlt(0);
326 // __ STOP("receiver class disagrees with MemberName.clazz");
327 __ bind(L_ok);
328 }
329 BLOCK_COMMENT("} check_receiver");
330 }
331 if (iid == vmIntrinsics::_linkToSpecial ||
332 iid == vmIntrinsics::_linkToStatic) {
333 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
334 }
335
336 // Live registers at this point:
337 // member_reg - MemberName that was the trailing argument
338 // temp1_recv_klass - klass of stacked receiver, if needed
339 // r1 ... r0 - compiler arguments (if compiled)
340
341 Label L_incompatible_class_change_error;
342 switch (iid) {
343 case vmIntrinsics::_linkToSpecial:
344 if (VerifyMethodHandles) {
345 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
346 }
347 __ load_heap_oop(rmethod, member_vmtarget);
348 __ access_load_word_at(T_ADDRESS, IN_HEAP, rmethod, vmtarget_method, noreg, noreg);
349 break;
350
351 case vmIntrinsics::_linkToStatic:
352 if (VerifyMethodHandles) {
353 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
354 }
355 __ load_heap_oop(rmethod, member_vmtarget);
356 __ access_load_word_at(T_ADDRESS, IN_HEAP, rmethod, vmtarget_method, noreg, noreg);
357 break;
358
359 case vmIntrinsics::_linkToVirtual:
360 {
361 // same as TemplateTable::invokevirtual,
362 // minus the CP setup and profiling:
363
364 if (VerifyMethodHandles) {
365 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
366 }
367
368 // pick out the vtable index from the MemberName, and then we can discard it:
369 Register temp2_index = temp2;
370 __ access_load_word_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
371
372 if (VerifyMethodHandles) {
373 Label L_index_ok;
374 __ cmp(temp2_index, 0U);
375 __ b(L_index_ok, Assembler::GE);
376 __ hlt(0);
377 __ BIND(L_index_ok);
378 }
379
380 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
381 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
382
383 // get target Method* & entry point
384 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rmethod);
385 break;
386 }
387
388 case vmIntrinsics::_linkToInterface:
389 {
390 // same as TemplateTable::invokeinterface
391 // (minus the CP setup and profiling, with different argument motion)
392 if (VerifyMethodHandles) {
393 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
394 }
395
396 Register temp3_intf = temp3;
397 __ load_heap_oop(temp3_intf, member_clazz);
398 load_klass_from_Class(_masm, temp3_intf);
399 __ verify_klass_ptr(temp3_intf);
400
401 Register rindex = rmethod;
402 __ access_load_word_at(T_ADDRESS, IN_HEAP, rindex, member_vmindex, noreg, noreg);
403 if (VerifyMethodHandles) {
404 Label L;
405 __ cmp(rindex, 0);
406 __ b(L, Assembler::GE);
407 __ hlt(0);
408 __ bind(L);
409 }
410
411 // given intf, index, and recv klass, dispatch to the implementation method
412 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
413 // note: next two args must be the same:
414 rindex, rmethod,
415 temp2,
416 L_incompatible_class_change_error);
417 break;
418 }
419
420 default:
421 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
422 break;
423 }
424
425 // live at this point: rmethod, r13 (if interpreted)
426
427 // After figuring out which concrete method to call, jump into it.
428 // Note that this works in the interpreter with no data motion.
429 // But the compiled version will require that r2_recv be shifted out.
430 __ verify_method_ptr(rmethod);
431 jump_from_method_handle(_masm, rmethod, temp1, for_compiler_entry);
432 if (iid == vmIntrinsics::_linkToInterface) {
433 __ bind(L_incompatible_class_change_error);
434 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
435 }
436 }
437 }
438
439 #ifndef PRODUCT
440 void trace_method_handle_stub(const char* adaptername,
441 oop mh,
442 intptr_t* saved_regs,
443 intptr_t* entry_sp) { }
444
445 // The stub wraps the arguments in a struct on the stack to avoid
446 // dealing with the different calling conventions for passing 6
447 // arguments.
448 struct MethodHandleStubArguments {
449 const char* adaptername;
450 oopDesc* mh;
451 intptr_t* saved_regs;
452 intptr_t* entry_sp;
453 };
454 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { }
455
456 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { }
457 #endif //PRODUCT