1 /*
2 * Copyright (c) 1997, 2017, 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/frame.inline.hpp"
34
35 #define __ _masm->
36
37 #ifdef PRODUCT
38 #define BLOCK_COMMENT(str) /* nothing */
39 #else
40 #define BLOCK_COMMENT(str) __ block_comment(str)
41 #endif
42
43 #define BIND(label) bind(label); BLOCK_COMMENT(#label ":")
44
45 void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) {
46 if (VerifyMethodHandles)
47 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class),
48 "MH argument is a Class");
49 __ ldr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes()));
50 }
51
52 #ifdef ASSERT
53 static int check_nonzero(const char* xname, int x) {
54 assert(x != 0, "%s should be nonzero", xname);
55 return x;
56 }
57 #define NONZERO(x) check_nonzero(#x, x)
58 #else //ASSERT
59 #define NONZERO(x) (x)
60 #endif //PRODUCT
61
62 #ifdef ASSERT
63 void MethodHandles::verify_klass(MacroAssembler* _masm,
64 Register obj, SystemDictionary::WKID klass_id,
65 const char* error_message) {
66 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id);
67 Klass* klass = SystemDictionary::well_known_klass(klass_id);
68 Register temp = rscratch2;
69 Register temp2 = rscratch1; // used by MacroAssembler::cmpptr
70 Label L_ok, L_bad;
71 BLOCK_COMMENT("verify_klass {");
72 __ verify_oop(obj);
73 __ cbz(obj, L_bad);
74 __ push(RegSet::of(temp, temp2), sp);
75 __ load_klass(temp, obj);
76 __ cmpptr(temp, ExternalAddress((address) klass_addr));
77 __ br(Assembler::EQ, L_ok);
78 intptr_t super_check_offset = klass->super_check_offset();
79 __ ldr(temp, Address(temp, super_check_offset));
80 __ cmpptr(temp, ExternalAddress((address) klass_addr));
81 __ br(Assembler::EQ, L_ok);
82 __ pop(RegSet::of(temp, temp2), sp);
83 __ bind(L_bad);
84 __ stop(error_message);
85 __ BIND(L_ok);
86 __ pop(RegSet::of(temp, temp2), sp);
87 BLOCK_COMMENT("} verify_klass");
88 }
89
90 void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { }
91
92 #endif //ASSERT
93
94 void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp,
95 bool for_compiler_entry) {
96 assert(method == rmethod, "interpreter calling convention");
97 Label L_no_such_method;
98 __ cbz(rmethod, L_no_such_method);
99 __ verify_method_ptr(method);
100
101 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) {
102 Label run_compiled_code;
103 // JVMTI events, such as single-stepping, are implemented partly by avoiding running
104 // compiled code in threads for which the event is enabled. Check here for
105 // interp_only_mode if these events CAN be enabled.
106
107 __ ldrb(rscratch1, Address(rthread, JavaThread::interp_only_mode_offset()));
108 __ cbnz(rscratch1, run_compiled_code);
109 __ ldr(rscratch1, Address(method, Method::interpreter_entry_offset()));
110 __ br(rscratch1);
111 __ BIND(run_compiled_code);
112 }
113
114 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() :
115 Method::from_interpreted_offset();
116 __ ldr(rscratch1,Address(method, entry_offset));
117 __ br(rscratch1);
118 __ bind(L_no_such_method);
119 __ far_jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry()));
120 }
121
122 void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm,
123 Register recv, Register method_temp,
124 Register temp2,
125 bool for_compiler_entry) {
126 BLOCK_COMMENT("jump_to_lambda_form {");
127 // This is the initial entry point of a lazy method handle.
128 // After type checking, it picks up the invoker from the LambdaForm.
129 assert_different_registers(recv, method_temp, temp2);
130 assert(recv != noreg, "required register");
131 assert(method_temp == rmethod, "required register for loading method");
132
133 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); });
134
135 // Load the invoker, as MH -> MH.form -> LF.vmentry
136 __ verify_oop(recv);
137 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes())));
138 __ verify_oop(method_temp);
139 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes())));
140 __ verify_oop(method_temp);
141 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes())));
142 __ verify_oop(method_temp);
143 __ ldr(method_temp, Address(method_temp, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes())));
144
145 if (VerifyMethodHandles && !for_compiler_entry) {
146 // make sure recv is already on stack
147 __ ldr(temp2, Address(method_temp, Method::const_offset()));
148 __ load_sized_value(temp2,
149 Address(temp2, ConstMethod::size_of_parameters_offset()),
150 sizeof(u2), /*is_signed*/ false);
151 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
152 Label L;
153 __ ldr(rscratch1, __ argument_address(temp2, -1));
154 __ cmp(recv, rscratch1);
155 __ br(Assembler::EQ, L);
156 __ ldr(r0, __ argument_address(temp2, -1));
157 __ hlt(0);
158 __ BIND(L);
159 }
160
161 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry);
162 BLOCK_COMMENT("} jump_to_lambda_form");
163 }
164
165 // Code generation
166 address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm,
167 vmIntrinsics::ID iid) {
168 const bool not_for_compiler_entry = false; // this is the interpreter entry
169 assert(is_signature_polymorphic(iid), "expected invoke iid");
170 if (iid == vmIntrinsics::_invokeGeneric ||
171 iid == vmIntrinsics::_compiledLambdaForm) {
172 // Perhaps surprisingly, the symbolic references visible to Java are not directly used.
173 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod.
174 // They all allow an appendix argument.
175 __ hlt(0); // empty stubs make SG sick
176 return NULL;
177 }
178
179 // r13: sender SP (must preserve; see prepare_to_jump_from_interpreted)
180 // rmethod: Method*
181 // r3: argument locator (parameter slot count, added to rsp)
182 // r1: used as temp to hold mh or receiver
183 // r0, r11: garbage temps, blown away
184 Register argp = r3; // argument list ptr, live on error paths
185 Register temp = r0;
186 Register mh = r1; // MH receiver; dies quickly and is recycled
187
188 // here's where control starts out:
189 __ align(CodeEntryAlignment);
190 address entry_point = __ pc();
191
192 if (VerifyMethodHandles) {
193 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2");
194
195 Label L;
196 BLOCK_COMMENT("verify_intrinsic_id {");
197 __ ldrh(rscratch1, Address(rmethod, Method::intrinsic_id_offset_in_bytes()));
198 __ cmp(rscratch1, (int) iid);
199 __ br(Assembler::EQ, L);
200 if (iid == vmIntrinsics::_linkToVirtual ||
201 iid == vmIntrinsics::_linkToSpecial) {
202 // could do this for all kinds, but would explode assembly code size
203 trace_method_handle(_masm, "bad Method*::intrinsic_id");
204 }
205 __ hlt(0);
206 __ bind(L);
207 BLOCK_COMMENT("} verify_intrinsic_id");
208 }
209
210 // First task: Find out how big the argument list is.
211 Address r3_first_arg_addr;
212 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid);
213 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic");
214 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) {
215 __ ldr(argp, Address(rmethod, Method::const_offset()));
216 __ load_sized_value(argp,
217 Address(argp, ConstMethod::size_of_parameters_offset()),
218 sizeof(u2), /*is_signed*/ false);
219 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), "");
220 r3_first_arg_addr = __ argument_address(argp, -1);
221 } else {
222 DEBUG_ONLY(argp = noreg);
223 }
224
225 if (!is_signature_polymorphic_static(iid)) {
226 __ ldr(mh, r3_first_arg_addr);
227 DEBUG_ONLY(argp = noreg);
228 }
229
230 // r3_first_arg_addr is live!
231
232 trace_method_handle_interpreter_entry(_masm, iid);
233 if (iid == vmIntrinsics::_invokeBasic) {
234 generate_method_handle_dispatch(_masm, iid, mh, noreg, not_for_compiler_entry);
235
236 } else {
237 // Adjust argument list by popping the trailing MemberName argument.
238 Register recv = noreg;
239 if (MethodHandles::ref_kind_has_receiver(ref_kind)) {
240 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack.
241 __ ldr(recv = r2, r3_first_arg_addr);
242 }
243 DEBUG_ONLY(argp = noreg);
244 Register rmember = rmethod; // MemberName ptr; incoming method ptr is dead now
245 __ pop(rmember); // extract last argument
246 generate_method_handle_dispatch(_masm, iid, recv, rmember, not_for_compiler_entry);
247 }
248
249 return entry_point;
250 }
251
252
253 void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm,
254 vmIntrinsics::ID iid,
255 Register receiver_reg,
256 Register member_reg,
257 bool for_compiler_entry) {
258 assert(is_signature_polymorphic(iid), "expected invoke iid");
259 // temps used in this code are not used in *either* compiled or interpreted calling sequences
260 Register temp1 = r10;
261 Register temp2 = r11;
262 Register temp3 = r14; // r13 is live by this point: it contains the sender SP
263 if (for_compiler_entry) {
264 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment");
265 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
266 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
267 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7);
268 }
269
270 assert_different_registers(temp1, temp2, temp3, receiver_reg);
271 assert_different_registers(temp1, temp2, temp3, member_reg);
272
273 if (iid == vmIntrinsics::_invokeBasic) {
274 // indirect through MH.form.vmentry.vmtarget
275 jump_to_lambda_form(_masm, receiver_reg, rmethod, temp1, for_compiler_entry);
276
277 } else {
278 // The method is a member invoker used by direct method handles.
279 if (VerifyMethodHandles) {
280 // make sure the trailing argument really is a MemberName (caller responsibility)
281 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName),
282 "MemberName required for invokeVirtual etc.");
283 }
284
285 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes()));
286 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes()));
287 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::method_offset_in_bytes()));
288 Address vmtarget_method( rmethod, NONZERO(java_lang_invoke_ResolvedMethodName::vmtarget_offset_in_bytes()));
289
290 Register temp1_recv_klass = temp1;
291 if (iid != vmIntrinsics::_linkToStatic) {
292 __ verify_oop(receiver_reg);
293 if (iid == vmIntrinsics::_linkToSpecial) {
294 // Don't actually load the klass; just null-check the receiver.
295 __ null_check(receiver_reg);
296 } else {
297 // load receiver klass itself
298 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes());
299 __ load_klass(temp1_recv_klass, receiver_reg);
300 __ verify_klass_ptr(temp1_recv_klass);
301 }
302 BLOCK_COMMENT("check_receiver {");
303 // The receiver for the MemberName must be in receiver_reg.
304 // Check the receiver against the MemberName.clazz
305 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) {
306 // Did not load it above...
307 __ load_klass(temp1_recv_klass, receiver_reg);
308 __ verify_klass_ptr(temp1_recv_klass);
309 }
310 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) {
311 Label L_ok;
312 Register temp2_defc = temp2;
313 __ load_heap_oop(temp2_defc, member_clazz);
314 load_klass_from_Class(_masm, temp2_defc);
315 __ verify_klass_ptr(temp2_defc);
316 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok);
317 // If we get here, the type check failed!
318 __ hlt(0);
319 // __ STOP("receiver class disagrees with MemberName.clazz");
320 __ bind(L_ok);
321 }
322 BLOCK_COMMENT("} check_receiver");
323 }
324 if (iid == vmIntrinsics::_linkToSpecial ||
325 iid == vmIntrinsics::_linkToStatic) {
326 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass
327 }
328
329 // Live registers at this point:
330 // member_reg - MemberName that was the trailing argument
331 // temp1_recv_klass - klass of stacked receiver, if needed
332 // r13 - interpreter linkage (if interpreted) ??? FIXME
333 // r1 ... r0 - compiler arguments (if compiled)
334
335 Label L_incompatible_class_change_error;
336 switch (iid) {
337 case vmIntrinsics::_linkToSpecial:
338 if (VerifyMethodHandles) {
339 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3);
340 }
341 __ load_heap_oop(rmethod, member_vmtarget);
342 __ ldr(rmethod, vmtarget_method);
343 break;
344
345 case vmIntrinsics::_linkToStatic:
346 if (VerifyMethodHandles) {
347 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3);
348 }
349 __ load_heap_oop(rmethod, member_vmtarget);
350 __ ldr(rmethod, vmtarget_method);
351 break;
352
353 case vmIntrinsics::_linkToVirtual:
354 {
355 // same as TemplateTable::invokevirtual,
356 // minus the CP setup and profiling:
357
358 if (VerifyMethodHandles) {
359 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3);
360 }
361
362 // pick out the vtable index from the MemberName, and then we can discard it:
363 Register temp2_index = temp2;
364 __ ldr(temp2_index, member_vmindex);
365
366 if (VerifyMethodHandles) {
367 Label L_index_ok;
368 __ cmpw(temp2_index, 0U);
369 __ br(Assembler::GE, L_index_ok);
370 __ hlt(0);
371 __ BIND(L_index_ok);
372 }
373
374 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget
375 // at this point. And VerifyMethodHandles has already checked clazz, if needed.
376
377 // get target Method* & entry point
378 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rmethod);
379 break;
380 }
381
382 case vmIntrinsics::_linkToInterface:
383 {
384 // same as TemplateTable::invokeinterface
385 // (minus the CP setup and profiling, with different argument motion)
386 if (VerifyMethodHandles) {
387 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3);
388 }
389
390 Register temp3_intf = temp3;
391 __ load_heap_oop(temp3_intf, member_clazz);
392 load_klass_from_Class(_masm, temp3_intf);
393 __ verify_klass_ptr(temp3_intf);
394
395 Register rindex = rmethod;
396 __ ldr(rindex, member_vmindex);
397 if (VerifyMethodHandles) {
398 Label L;
399 __ cmpw(rindex, 0U);
400 __ br(Assembler::GE, L);
401 __ hlt(0);
402 __ bind(L);
403 }
404
405 // given intf, index, and recv klass, dispatch to the implementation method
406 __ lookup_interface_method(temp1_recv_klass, temp3_intf,
407 // note: next two args must be the same:
408 rindex, rmethod,
409 temp2,
410 L_incompatible_class_change_error);
411 break;
412 }
413
414 default:
415 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid));
416 break;
417 }
418
419 // live at this point: rmethod, r13 (if interpreted)
420
421 // After figuring out which concrete method to call, jump into it.
422 // Note that this works in the interpreter with no data motion.
423 // But the compiled version will require that r2_recv be shifted out.
424 __ verify_method_ptr(rmethod);
425 jump_from_method_handle(_masm, rmethod, temp1, for_compiler_entry);
426 if (iid == vmIntrinsics::_linkToInterface) {
427 __ bind(L_incompatible_class_change_error);
428 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry()));
429 }
430 }
431 }
432
433 #ifndef PRODUCT
434 void trace_method_handle_stub(const char* adaptername,
435 oop mh,
436 intptr_t* saved_regs,
437 intptr_t* entry_sp) { }
438
439 // The stub wraps the arguments in a struct on the stack to avoid
440 // dealing with the different calling conventions for passing 6
441 // arguments.
442 struct MethodHandleStubArguments {
443 const char* adaptername;
444 oopDesc* mh;
445 intptr_t* saved_regs;
446 intptr_t* entry_sp;
447 };
448 void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { }
449
450 void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { }
451 #endif //PRODUCT