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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "asm/macroAssembler.hpp"
28 #include "classfile/javaClasses.inline.hpp"
29 #include "interpreter/interpreter.hpp"
30 #include "interpreter/interpreterRuntime.hpp"
31 #include "memory/allocation.inline.hpp"
32 #include "prims/methodHandles.hpp"
33 #include "runtime/flags/flagSetting.hpp"
34 #include "runtime/frame.inline.hpp"
35
36 #define __ _masm->
37
38 #ifdef PRODUCT
39 #define BLOCK_COMMENT(str) /* nothing */
40 #else
41 #define BLOCK_COMMENT(str) __ block_comment(str)
42 #endif
43
44 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
45
46 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
47 if (VerifyMethodHandles)
48 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
49 "MH argument is a Class");
50 __ ldr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
51 }
52
53 #ifdef ASSERT
54 static int check_nonzero(const char* xname, int x) {
55 assert(x != 0, "%s should be nonzero", xname);
56 return x;
57 }
58 #define NONZERO(x) check_nonzero(#x, x)
59 #else //ASSERT
60 #define NONZERO(x) (x)
61 #endif //PRODUCT
62
63 #ifdef ASSERT
64 void MethodHandles::verify_klass(MacroAssembler* _masm,
65 Register obj, SystemDictionary::WKID klass_id,
66 const char* error_message) {
67 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
68 Klass* klass = SystemDictionary::well_known_klass(klass_id);
69 Register temp = rscratch2;
70 Register temp2 = rscratch1; // used by MacroAssembler::cmpptr
71 Label L_ok, L_bad;
72 BLOCK_COMMENT("verify_klass {");
73 __ verify_oop(obj);
74 __ cbz(obj, L_bad);
75 __ push(RegSet::of(temp, temp2), sp);
76 __ load_klass(temp, obj);
77 __ cmpptr(temp, ExternalAddress((address) klass_addr));
78 __ br(Assembler::EQ, L_ok);
79 intptr_t super_check_offset = klass->super_check_offset();
80 __ ldr(temp, Address(temp, super_check_offset));
81 __ cmpptr(temp, ExternalAddress((address) klass_addr));
82 __ br(Assembler::EQ, L_ok);
83 __ pop(RegSet::of(temp, temp2), sp);
84 __ bind(L_bad);
85 __ stop(error_message);
86 __ BIND(L_ok);
87 __ pop(RegSet::of(temp, temp2), sp);
88 BLOCK_COMMENT("} verify_klass");
89 }
90
91 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { }
92
93 #endif //ASSERT
94
95 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
96 bool for_compiler_entry) {
97 assert(method == rmethod, "interpreter calling convention");
98 Label L_no_such_method;
99 __ cbz(rmethod, L_no_such_method);
100 __ verify_method_ptr(method);
101
102 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
103 Label run_compiled_code;
104 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
105 // compiled code in threads for which the event is enabled. Check here for
106 // interp_only_mode if these events CAN be enabled.
107
108 __ ldrb(rscratch1, Address(rthread, JavaThread::interp_only_mode_offset()));
109 __ cbnz(rscratch1, run_compiled_code);
110 __ ldr(rscratch1, Address(method, Method::interpreter_entry_offset()));
111 __ br(rscratch1);
112 __ BIND(run_compiled_code);
113 }
114
115 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
116 Method::from_interpreted_offset();
117 __ ldr(rscratch1,Address(method, entry_offset));
118 __ br(rscratch1);
119 __ bind(L_no_such_method);
120 __ far_jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
121 }
122
123 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
124 Register recv, Register method_temp,
125 Register temp2,
126 bool for_compiler_entry) {
127 BLOCK_COMMENT("jump_to_lambda_form {");
128 // This is the initial entry point of a lazy method handle.
129 // After type checking, it picks up the invoker from the LambdaForm.
130 assert_different_registers(recv, method_temp, temp2);
131 assert(recv != noreg, "required register");
132 assert(method_temp == rmethod, "required register for loading method");
133
134 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
135
136 // Load the invoker, as MH -> MH.form -> LF.vmentry
137 __ verify_oop(recv);
138 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));
139 __ verify_oop(method_temp);
140 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));
141 __ verify_oop(method_temp);
142 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())));
143 __ verify_oop(method_temp);
144 __ ldr(method_temp, Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())));
145
146 if (VerifyMethodHandles && !for_compiler_entry) {
147 // make sure recv is already on stack
148 __ ldr(temp2, Address(method_temp, Method::const_offset()));
149 __ load_sized_value(temp2,
150 Address(temp2, ConstMethod::size_of_parameters_offset()),
151 sizeof(u2), /*is_signed*/ false);
152 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
153 Label L;
154 __ ldr(rscratch1, __ argument_address(temp2, -1));
155 __ cmp(recv, rscratch1);
156 __ br(Assembler::EQ, L);
157 __ ldr(r0, __ argument_address(temp2, -1));
158 __ hlt(0);
159 __ BIND(L);
160 }
161
162 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
163 BLOCK_COMMENT("} jump_to_lambda_form");
164 }
165
166 // Code generation
167 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
168 vmIntrinsics::ID iid) {
169 const bool not_for_compiler_entry = false; // this is the interpreter entry
170 assert(is_signature_polymorphic(iid), "expected invoke iid");
171 if (iid == vmIntrinsics::_invokeGeneric ||
172 iid == vmIntrinsics::_compiledLambdaForm) {
173 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
174 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
175 // They all allow an appendix argument.
176 __ hlt(0); // empty stubs make SG sick
177 return NULL;
178 }
179
180 // r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
181 // rmethod: Method*
182 // r3: argument locator (parameter slot count, added to rsp)
183 // r1: used as temp to hold mh or receiver
184 // r0, r11: garbage temps, blown away
185 Register argp = r3; // argument list ptr, live on error paths
186 Register temp = r0;
187 Register mh = r1; // MH receiver; dies quickly and is recycled
188
189 // here's where control starts out:
190 __ align(CodeEntryAlignment);
191 address entry_point = __ pc();
192
193 if (VerifyMethodHandles) {
194 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
195
196 Label L;
197 BLOCK_COMMENT("verify_intrinsic_id {");
198 __ ldrh(rscratch1, Address(rmethod, Method::intrinsic_id_offset_in_bytes()));
199 __ cmp(rscratch1, (int) iid);
200 __ br(Assembler::EQ, L);
201 if (iid == vmIntrinsics::_linkToVirtual ||
202 iid == vmIntrinsics::_linkToSpecial) {
203 // could do this for all kinds, but would explode assembly code size
204 trace_method_handle(_masm, "bad Method*::intrinsic_id");
205 }
206 __ hlt(0);
207 __ bind(L);
208 BLOCK_COMMENT("} verify_intrinsic_id");
209 }
210
211 // First task: Find out how big the argument list is.
212 Address r3_first_arg_addr;
213 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
214 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
215 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
216 __ ldr(argp, Address(rmethod, Method::const_offset()));
217 __ load_sized_value(argp,
218 Address(argp, ConstMethod::size_of_parameters_offset()),
219 sizeof(u2), /*is_signed*/ false);
220 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
221 r3_first_arg_addr = __ argument_address(argp, -1);
222 } else {
223 DEBUG_ONLY(argp = noreg);
224 }
225
226 if (!is_signature_polymorphic_static(iid)) {
227 __ ldr(mh, r3_first_arg_addr);
228 DEBUG_ONLY(argp = noreg);
229 }
230
231 // r3_first_arg_addr is live!
232
233 trace_method_handle_interpreter_entry(_masm, iid);
234 if (iid == vmIntrinsics::_invokeBasic) {
235 generate_method_handle_dispatch(_masm, iid, mh, noreg, not_for_compiler_entry);
236
237 } else {
238 // Adjust argument list by popping the trailing MemberName argument.
239 Register recv = noreg;
240 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
241 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
242 __ ldr(recv = r2, r3_first_arg_addr);
243 }
244 DEBUG_ONLY(argp = noreg);
245 Register rmember = rmethod; // MemberName ptr; incoming method ptr is dead now
246 __ pop(rmember); // extract last argument
247 generate_method_handle_dispatch(_masm, iid, recv, rmember, not_for_compiler_entry);
248 }
249
250 return entry_point;
251 }
252
253
254 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
255 vmIntrinsics::ID iid,
256 Register receiver_reg,
257 Register member_reg,
258 bool for_compiler_entry) {
259 assert(is_signature_polymorphic(iid), "expected invoke iid");
260 // temps used in this code are not used in *either* compiled or interpreted calling sequences
261 Register temp1 = r10;
262 Register temp2 = r11;
263 Register temp3 = r14; // r13 is live by this point: it contains the sender SP
264 if (for_compiler_entry) {
265 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
266 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
267 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
268 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
269 }
270
271 assert_different_registers(temp1, temp2, temp3, receiver_reg);
272 assert_different_registers(temp1, temp2, temp3, member_reg);
273
274 if (iid == vmIntrinsics::_invokeBasic) {
275 // indirect through MH.form.vmentry.vmtarget
276 jump_to_lambda_form(_masm, receiver_reg, rmethod, temp1, for_compiler_entry);
277
278 } else {
279 // The method is a member invoker used by direct method handles.
280 if (VerifyMethodHandles) {
281 // make sure the trailing argument really is a MemberName (caller responsibility)
282 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),
283 "MemberName required for invokeVirtual etc.");
284 }
285
286 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
287 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
288 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()));
289 Address vmtarget_method( rmethod, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()));
290
291 Register temp1_recv_klass = temp1;
292 if (iid != vmIntrinsics::_linkToStatic) {
293 __ verify_oop(receiver_reg);
294 if (iid == vmIntrinsics::_linkToSpecial) {
295 // Don't actually load the klass; just null-check the receiver.
296 __ null_check(receiver_reg);
297 } else {
298 // load receiver klass itself
299 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
300 __ load_klass(temp1_recv_klass, receiver_reg);
301 __ verify_klass_ptr(temp1_recv_klass);
302 }
303 BLOCK_COMMENT("check_receiver {");
304 // The receiver for the MemberName must be in receiver_reg.
305 // Check the receiver against the MemberName.clazz
306 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
307 // Did not load it above...
308 __ load_klass(temp1_recv_klass, receiver_reg);
309 __ verify_klass_ptr(temp1_recv_klass);
310 }
311 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
312 Label L_ok;
313 Register temp2_defc = temp2;
314 __ load_heap_oop(temp2_defc, member_clazz);
315 load_klass_from_Class(_masm, temp2_defc);
316 __ verify_klass_ptr(temp2_defc);
317 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
318 // If we get here, the type check failed!
319 __ hlt(0);
320 // __ STOP("receiver class disagrees with MemberName.clazz");
321 __ bind(L_ok);
322 }
323 BLOCK_COMMENT("} check_receiver");
324 }
325 if (iid == vmIntrinsics::_linkToSpecial ||
326 iid == vmIntrinsics::_linkToStatic) {
327 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
328 }
329
330 // Live registers at this point:
331 // member_reg - MemberName that was the trailing argument
332 // temp1_recv_klass - klass of stacked receiver, if needed
333 // r13 - interpreter linkage (if interpreted) ??? FIXME
334 // r1 ... r0 - compiler arguments (if compiled)
335
336 Label L_incompatible_class_change_error;
337 switch (iid) {
338 case vmIntrinsics::_linkToSpecial:
339 if (VerifyMethodHandles) {
340 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
341 }
342 __ load_heap_oop(rmethod, member_vmtarget);
343 __ ldr(rmethod, vmtarget_method);
344 break;
345
346 case vmIntrinsics::_linkToStatic:
347 if (VerifyMethodHandles) {
348 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
349 }
350 __ load_heap_oop(rmethod, member_vmtarget);
351 __ ldr(rmethod, vmtarget_method);
352 break;
353
354 case vmIntrinsics::_linkToVirtual:
355 {
356 // same as TemplateTable::invokevirtual,
357 // minus the CP setup and profiling:
358
359 if (VerifyMethodHandles) {
360 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
361 }
362
363 // pick out the vtable index from the MemberName, and then we can discard it:
364 Register temp2_index = temp2;
365 __ ldr(temp2_index, member_vmindex);
366
367 if (VerifyMethodHandles) {
368 Label L_index_ok;
369 __ cmpw(temp2_index, 0U);
370 __ br(Assembler::GE, L_index_ok);
371 __ hlt(0);
372 __ BIND(L_index_ok);
373 }
374
375 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
376 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
377
378 // get target Method* & entry point
379 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rmethod);
380 break;
381 }
382
383 case vmIntrinsics::_linkToInterface:
384 {
385 // same as TemplateTable::invokeinterface
386 // (minus the CP setup and profiling, with different argument motion)
387 if (VerifyMethodHandles) {
388 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
389 }
390
391 Register temp3_intf = temp3;
392 __ load_heap_oop(temp3_intf, member_clazz);
393 load_klass_from_Class(_masm, temp3_intf);
394 __ verify_klass_ptr(temp3_intf);
395
396 Register rindex = rmethod;
397 __ ldr(rindex, member_vmindex);
398 if (VerifyMethodHandles) {
399 Label L;
400 __ cmpw(rindex, 0U);
401 __ br(Assembler::GE, L);
402 __ hlt(0);
403 __ bind(L);
404 }
405
406 // given intf, index, and recv klass, dispatch to the implementation method
407 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
408 // note: next two args must be the same:
409 rindex, rmethod,
410 temp2,
411 L_incompatible_class_change_error);
412 break;
413 }
414
415 default:
416 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
417 break;
418 }
419
420 // live at this point: rmethod, r13 (if interpreted)
421
422 // After figuring out which concrete method to call, jump into it.
423 // Note that this works in the interpreter with no data motion.
424 // But the compiled version will require that r2_recv be shifted out.
425 __ verify_method_ptr(rmethod);
426 jump_from_method_handle(_masm, rmethod, temp1, for_compiler_entry);
427 if (iid == vmIntrinsics::_linkToInterface) {
428 __ bind(L_incompatible_class_change_error);
429 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
430 }
431 }
432 }
433
434 #ifndef PRODUCT
435 void trace_method_handle_stub(const char* adaptername,
436 oop mh,
437 intptr_t* saved_regs,
438 intptr_t* entry_sp) { }
439
440 // The stub wraps the arguments in a struct on the stack to avoid
441 // dealing with the different calling conventions for passing 6
442 // arguments.
443 struct MethodHandleStubArguments {
444 const char* adaptername;
445 oopDesc* mh;
446 intptr_t* saved_regs;
447 intptr_t* entry_sp;
448 };
449 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { }
450
451 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { }
452 #endif //PRODUCT