1 /*
2 * Copyright (c) 1997, 2020, Oracle and/or its affiliates. All rights reserved.
3 * Copyright (c) 2014, Red Hat Inc. All rights reserved.
4 * Copyright (c) 2020, 2022, Huawei Technologies Co., Ltd. All rights reserved.
5 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
6 *
7 * This code is free software; you can redistribute it and/or modify it
8 * under the terms of the GNU General Public License version 2 only, as
9 * published by the Free Software Foundation.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 *
25 */
26
27 #include "precompiled.hpp"
28 #include "asm/macroAssembler.hpp"
29 #include "classfile/javaClasses.inline.hpp"
30 #include "classfile/vmClasses.hpp"
31 #include "interpreter/interpreter.hpp"
32 #include "interpreter/interpreterRuntime.hpp"
33 #include "memory/allocation.inline.hpp"
34 #include "prims/jvmtiExport.hpp"
35 #include "prims/methodHandles.hpp"
36 #include "runtime/flags/flagSetting.hpp"
37 #include "runtime/frame.inline.hpp"
38 #include "runtime/stubRoutines.hpp"
39
40 #define __ _masm->
41
42 #ifdef PRODUCT
43 #define BLOCK_COMMENT(str) /* nothing */
44 #else
45 #define BLOCK_COMMENT(str) __ block_comment(str)
46 #endif
47
48 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
49
50 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
51 assert_cond(_masm != NULL);
52 if (VerifyMethodHandles) {
53 verify_klass(_masm, klass_reg, VM_CLASS_ID(java_lang_Class),
54 "MH argument is a Class");
55 }
56 __ ld(klass_reg, Address(klass_reg, java_lang_Class::klass_offset()));
57 }
58
59 #ifdef ASSERT
60 static int check_nonzero(const char* xname, int x) {
61 assert(x != 0, "%s should be nonzero", xname);
62 return x;
63 }
64 #define NONZERO(x) check_nonzero(#x, x)
65 #else //ASSERT
66 #define NONZERO(x) (x)
67 #endif //PRODUCT
68
69 #ifdef ASSERT
70 void MethodHandles::verify_klass(MacroAssembler* _masm,
71 Register obj, vmClassID klass_id,
72 const char* error_message) {
73 assert_cond(_masm != NULL);
74 InstanceKlass** klass_addr = vmClasses::klass_addr_at(klass_id);
75 Klass* klass = vmClasses::klass_at(klass_id);
76 Register temp1 = t1;
77 Register temp2 = t0; // used by MacroAssembler::cmpptr
78 Label L_ok, L_bad;
79 BLOCK_COMMENT("verify_klass {");
80 __ verify_oop(obj);
81 __ beqz(obj, L_bad);
82 __ push_reg(RegSet::of(temp1, temp2), sp);
83 __ load_klass(temp1, obj, temp2);
84 __ cmpptr(temp1, ExternalAddress((address) klass_addr), L_ok);
85 intptr_t super_check_offset = klass->super_check_offset();
86 __ ld(temp1, Address(temp1, super_check_offset));
87 __ cmpptr(temp1, ExternalAddress((address) klass_addr), L_ok);
88 __ pop_reg(RegSet::of(temp1, temp2), sp);
89 __ bind(L_bad);
90 __ stop(error_message);
91 __ BIND(L_ok);
92 __ pop_reg(RegSet::of(temp1, 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_cond(_masm != NULL);
103 assert(method == xmethod, "interpreter calling convention");
104 Label L_no_such_method;
105 __ beqz(xmethod, L_no_such_method);
106 __ verify_method_ptr(method);
107
108 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
109 Label run_compiled_code;
110 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
111 // compiled code in threads for which the event is enabled. Check here for
112 // interp_only_mode if these events CAN be enabled.
113
114 __ lwu(t0, Address(xthread, JavaThread::interp_only_mode_offset()));
115 __ beqz(t0, run_compiled_code);
116 __ ld(t0, Address(method, Method::interpreter_entry_offset()));
117 __ jr(t0);
118 __ BIND(run_compiled_code);
119 }
120
121 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
122 Method::from_interpreted_offset();
123 __ ld(t0,Address(method, entry_offset));
124 __ jr(t0);
125 __ bind(L_no_such_method);
126 __ far_jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
127 }
128
129 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
130 Register recv, Register method_temp,
131 Register temp2,
132 bool for_compiler_entry) {
133 assert_cond(_masm != NULL);
134 BLOCK_COMMENT("jump_to_lambda_form {");
135 // This is the initial entry point of a lazy method handle.
136 // After type checking, it picks up the invoker from the LambdaForm.
137 assert_different_registers(recv, method_temp, temp2);
138 assert(recv != noreg, "required register");
139 assert(method_temp == xmethod, "required register for loading method");
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())), temp2);
144 __ verify_oop(method_temp);
145 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset())), temp2);
146 __ verify_oop(method_temp);
147 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset())), temp2);
148 __ verify_oop(method_temp);
149 __ access_load_at(T_ADDRESS, IN_HEAP, method_temp, Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset())), noreg, noreg);
150
151 if (VerifyMethodHandles && !for_compiler_entry) {
152 // make sure recv is already on stack
153 __ ld(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 Label L;
158 __ ld(t0, __ argument_address(temp2, -1));
159 __ beq(recv, t0, L);
160 __ ld(x10, __ argument_address(temp2, -1));
161 __ ebreak();
162 __ BIND(L);
163 }
164
165 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
166 BLOCK_COMMENT("} jump_to_lambda_form");
167 }
168
169 // Code generation
170 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
171 vmIntrinsics::ID iid) {
172 assert_cond(_masm != NULL);
173 const bool not_for_compiler_entry = false; // this is the interpreter entry
174 assert(is_signature_polymorphic(iid), "expected invoke iid");
175 if (iid == vmIntrinsics::_invokeGeneric ||
176 iid == vmIntrinsics::_compiledLambdaForm) {
177 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
178 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
179 // They all allow an appendix argument.
180 __ ebreak(); // empty stubs make SG sick
181 return NULL;
182 }
183
184 // No need in interpreter entry for linkToNative for now.
185 // Interpreter calls compiled entry through i2c.
186 if (iid == vmIntrinsics::_linkToNative) {
187 __ ebreak();
188 return NULL;
189 }
190
191 // x30: sender SP (must preserve; see prepare_to_jump_from_interpreted)
192 // xmethod: Method*
193 // x13: argument locator (parameter slot count, added to sp)
194 // x11: used as temp to hold mh or receiver
195 // x10, x29: garbage temps, blown away
196 Register argp = x13; // argument list ptr, live on error paths
197 Register mh = x11; // MH receiver; dies quickly and is recycled
198
199 // here's where control starts out:
200 __ align(CodeEntryAlignment);
201 address entry_point = __ pc();
202
203 if (VerifyMethodHandles) {
204 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
205
206 Label L;
207 BLOCK_COMMENT("verify_intrinsic_id {");
208 __ lhu(t0, Address(xmethod, Method::intrinsic_id_offset_in_bytes()));
209 __ mv(t1, (int) iid);
210 __ beq(t0, t1, L);
211 if (iid == vmIntrinsics::_linkToVirtual ||
212 iid == vmIntrinsics::_linkToSpecial) {
213 // could do this for all kinds, but would explode assembly code size
214 trace_method_handle(_masm, "bad Method*::intrinsic_id");
215 }
216 __ ebreak();
217 __ bind(L);
218 BLOCK_COMMENT("} verify_intrinsic_id");
219 }
220
221 // First task: Find out how big the argument list is.
222 Address x13_first_arg_addr;
223 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
224 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
225 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
226 __ ld(argp, Address(xmethod, Method::const_offset()));
227 __ load_sized_value(argp,
228 Address(argp, ConstMethod::size_of_parameters_offset()),
229 sizeof(u2), /*is_signed*/ false);
230 x13_first_arg_addr = __ argument_address(argp, -1);
231 } else {
232 DEBUG_ONLY(argp = noreg);
233 }
234
235 if (!is_signature_polymorphic_static(iid)) {
236 __ ld(mh, x13_first_arg_addr);
237 DEBUG_ONLY(argp = noreg);
238 }
239
240 // x13_first_arg_addr is live!
241
242 trace_method_handle_interpreter_entry(_masm, iid);
243 if (iid == vmIntrinsics::_invokeBasic) {
244 generate_method_handle_dispatch(_masm, iid, mh, noreg, not_for_compiler_entry);
245 } else {
246 // Adjust argument list by popping the trailing MemberName argument.
247 Register recv = noreg;
248 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
249 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
250 __ ld(recv = x12, x13_first_arg_addr);
251 }
252 DEBUG_ONLY(argp = noreg);
253 Register xmember = xmethod; // MemberName ptr; incoming method ptr is dead now
254 __ pop_reg(xmember); // extract last argument
255 generate_method_handle_dispatch(_masm, iid, recv, xmember, not_for_compiler_entry);
256 }
257
258 return entry_point;
259 }
260
261
262 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
263 vmIntrinsics::ID iid,
264 Register receiver_reg,
265 Register member_reg,
266 bool for_compiler_entry) {
267 assert_cond(_masm != NULL);
268 assert(is_signature_polymorphic(iid), "expected invoke iid");
269 // temps used in this code are not used in *either* compiled or interpreted calling sequences
270 Register temp1 = x7;
271 Register temp2 = x28;
272 Register temp3 = x29; // x30 is live by this point: it contains the sender SP
273 if (for_compiler_entry) {
274 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
275 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
276 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
277 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
278 }
279
280 assert_different_registers(temp1, temp2, temp3, receiver_reg);
281 assert_different_registers(temp1, temp2, temp3, member_reg);
282
283 if (iid == vmIntrinsics::_invokeBasic || iid == vmIntrinsics::_linkToNative) {
284 if (iid == vmIntrinsics::_linkToNative) {
285 assert(for_compiler_entry, "only compiler entry is supported");
286 }
287 // indirect through MH.form.vmentry.vmtarget
288 jump_to_lambda_form(_masm, receiver_reg, xmethod, temp1, for_compiler_entry);
289 } else {
290 // The method is a member invoker used by direct method handles.
291 if (VerifyMethodHandles) {
292 // make sure the trailing argument really is a MemberName (caller responsibility)
293 verify_klass(_masm, member_reg, VM_CLASS_ID(java_lang_invoke_MemberName),
294 "MemberName required for invokeVirtual etc.");
295 }
296
297 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset()));
298 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset()));
299 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset()));
300 Address vmtarget_method( xmethod, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset()));
301
302 Register temp1_recv_klass = temp1;
303 if (iid != vmIntrinsics::_linkToStatic) {
304 __ verify_oop(receiver_reg);
305 if (iid == vmIntrinsics::_linkToSpecial) {
306 // Don't actually load the klass; just null-check the receiver.
307 __ null_check(receiver_reg);
308 } else {
309 // load receiver klass itself
310 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
311 __ load_klass(temp1_recv_klass, receiver_reg);
312 __ verify_klass_ptr(temp1_recv_klass);
313 }
314 BLOCK_COMMENT("check_receiver {");
315 // The receiver for the MemberName must be in receiver_reg.
316 // Check the receiver against the MemberName.clazz
317 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
318 // Did not load it above...
319 __ load_klass(temp1_recv_klass, receiver_reg);
320 __ verify_klass_ptr(temp1_recv_klass);
321 }
322 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
323 Label L_ok;
324 Register temp2_defc = temp2;
325 __ load_heap_oop(temp2_defc, member_clazz, temp3);
326 load_klass_from_Class(_masm, temp2_defc);
327 __ verify_klass_ptr(temp2_defc);
328 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
329 // If we get here, the type check failed!
330 __ ebreak();
331 __ bind(L_ok);
332 }
333 BLOCK_COMMENT("} check_receiver");
334 }
335 if (iid == vmIntrinsics::_linkToSpecial ||
336 iid == vmIntrinsics::_linkToStatic) {
337 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
338 }
339
340 // Live registers at this point:
341 // member_reg - MemberName that was the trailing argument
342 // temp1_recv_klass - klass of stacked receiver, if needed
343 // x30 - interpreter linkage (if interpreted)
344 // x11 ... x10 - compiler arguments (if compiled)
345
346 Label L_incompatible_class_change_error;
347 switch (iid) {
348 case vmIntrinsics::_linkToSpecial:
349 if (VerifyMethodHandles) {
350 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
351 }
352 __ load_heap_oop(xmethod, member_vmtarget);
353 __ access_load_at(T_ADDRESS, IN_HEAP, xmethod, vmtarget_method, noreg, noreg);
354 break;
355
356 case vmIntrinsics::_linkToStatic:
357 if (VerifyMethodHandles) {
358 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
359 }
360 __ load_heap_oop(xmethod, member_vmtarget);
361 __ access_load_at(T_ADDRESS, IN_HEAP, xmethod, vmtarget_method, noreg, noreg);
362 break;
363
364 case vmIntrinsics::_linkToVirtual:
365 {
366 // same as TemplateTable::invokevirtual,
367 // minus the CP setup and profiling:
368
369 if (VerifyMethodHandles) {
370 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
371 }
372
373 // pick out the vtable index from the MemberName, and then we can discard it:
374 Register temp2_index = temp2;
375 __ access_load_at(T_ADDRESS, IN_HEAP, temp2_index, member_vmindex, noreg, noreg);
376
377 if (VerifyMethodHandles) {
378 Label L_index_ok;
379 __ bgez(temp2_index, L_index_ok);
380 __ ebreak();
381 __ BIND(L_index_ok);
382 }
383
384 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
385 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
386
387 // get target Method* & entry point
388 __ lookup_virtual_method(temp1_recv_klass, temp2_index, xmethod);
389 break;
390 }
391
392 case vmIntrinsics::_linkToInterface:
393 {
394 // same as TemplateTable::invokeinterface
395 // (minus the CP setup and profiling, with different argument motion)
396 if (VerifyMethodHandles) {
397 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
398 }
399
400 Register temp3_intf = temp3;
401 __ load_heap_oop(temp3_intf, member_clazz);
402 load_klass_from_Class(_masm, temp3_intf);
403 __ verify_klass_ptr(temp3_intf);
404
405 Register rindex = xmethod;
406 __ access_load_at(T_ADDRESS, IN_HEAP, rindex, member_vmindex, noreg, noreg);
407 if (VerifyMethodHandles) {
408 Label L;
409 __ bgez(rindex, L);
410 __ ebreak();
411 __ bind(L);
412 }
413
414 // given intf, index, and recv klass, dispatch to the implementation method
415 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
416 // note: next two args must be the same:
417 rindex, xmethod,
418 temp2,
419 L_incompatible_class_change_error);
420 break;
421 }
422
423 default:
424 fatal("unexpected intrinsic %d: %s", vmIntrinsics::as_int(iid), vmIntrinsics::name_at(iid));
425 break;
426 }
427
428 // live at this point: xmethod, x30 (if interpreted)
429
430 // After figuring out which concrete method to call, jump into it.
431 // Note that this works in the interpreter with no data motion.
432 // But the compiled version will require that r2_recv be shifted out.
433 __ verify_method_ptr(xmethod);
434 jump_from_method_handle(_masm, xmethod, temp1, for_compiler_entry);
435 if (iid == vmIntrinsics::_linkToInterface) {
436 __ bind(L_incompatible_class_change_error);
437 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
438 }
439 }
440
441 }
442
443 #ifndef PRODUCT
444 void trace_method_handle_stub(const char* adaptername,
445 oopDesc* mh,
446 intptr_t* saved_regs,
447 intptr_t* entry_sp) { }
448
449 // The stub wraps the arguments in a struct on the stack to avoid
450 // dealing with the different calling conventions for passing 6
451 // arguments.
452 struct MethodHandleStubArguments {
453 const char* adaptername;
454 oopDesc* mh;
455 intptr_t* saved_regs;
456 intptr_t* entry_sp;
457 };
458 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { }
459
460 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { }
461 #endif //PRODUCT