1/* 2 * Copyright (c) 1997, 2015, 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 34#define __ _masm-> 35 36#ifdef PRODUCT 37#define BLOCK_COMMENT(str) /* nothing */ 38#else 39#define BLOCK_COMMENT(str) __ block_comment(str) 40#endif 41 42#define BIND(label) bind(label); BLOCK_COMMENT(#label ":") 43 44void MethodHandles::load_klass_from_Class(MacroAssembler* _masm, Register klass_reg) { 45 if (VerifyMethodHandles) 46 verify_klass(_masm, klass_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_Class), 47 "MH argument is a Class"); 48 __ ldr(klass_reg, Address(klass_reg, java_lang_Class::klass_offset_in_bytes())); 49} 50 51#ifdef ASSERT 52static int check_nonzero(const char* xname, int x) { 53 assert(x != 0, "%s should be nonzero", xname); 54 return x; 55} 56#define NONZERO(x) check_nonzero(#x, x) 57#else //ASSERT 58#define NONZERO(x) (x) 59#endif //PRODUCT 60 61#ifdef ASSERT 62void MethodHandles::verify_klass(MacroAssembler* _masm, 63 Register obj, SystemDictionary::WKID klass_id, 64 const char* error_message) { 65 InstanceKlass** klass_addr = SystemDictionary::well_known_klass_addr(klass_id); 66 KlassHandle klass = SystemDictionary::well_known_klass(klass_id); 67 Register temp = rscratch2; 68 Register temp2 = rscratch1; // used by MacroAssembler::cmpptr 69 Label L_ok, L_bad; 70 BLOCK_COMMENT("verify_klass {"); 71 __ verify_oop(obj); 72 __ cbz(obj, L_bad); 73 __ push(RegSet::of(temp, temp2), sp); 74 __ load_klass(temp, obj); 75 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 76 __ br(Assembler::EQ, L_ok); 77 intptr_t super_check_offset = klass->super_check_offset(); 78 __ ldr(temp, Address(temp, super_check_offset)); 79 __ cmpptr(temp, ExternalAddress((address) klass_addr)); 80 __ br(Assembler::EQ, L_ok); 81 __ pop(RegSet::of(temp, temp2), sp); 82 __ bind(L_bad); 83 __ stop(error_message); 84 __ BIND(L_ok); 85 __ pop(RegSet::of(temp, temp2), sp); 86 BLOCK_COMMENT("} verify_klass"); 87} 88 89void MethodHandles::verify_ref_kind(MacroAssembler* _masm, int ref_kind, Register member_reg, Register temp) { } 90 91#endif //ASSERT 92 93void MethodHandles::jump_from_method_handle(MacroAssembler* _masm, Register method, Register temp, 94 bool for_compiler_entry) { 95 assert(method == rmethod, "interpreter calling convention"); 96 Label L_no_such_method; 97 __ cbz(rmethod, L_no_such_method); 98 __ verify_method_ptr(method); 99 100 if (!for_compiler_entry && JvmtiExport::can_post_interpreter_events()) { 101 Label run_compiled_code; 102 // JVMTI events, such as single-stepping, are implemented partly by avoiding running 103 // compiled code in threads for which the event is enabled. Check here for 104 // interp_only_mode if these events CAN be enabled. 105 106 __ ldrb(rscratch1, Address(rthread, JavaThread::interp_only_mode_offset())); 107 __ cbnz(rscratch1, run_compiled_code); 108 __ ldr(rscratch1, Address(method, Method::interpreter_entry_offset())); 109 __ br(rscratch1); 110 __ BIND(run_compiled_code); 111 } 112 113 const ByteSize entry_offset = for_compiler_entry ? Method::from_compiled_offset() : 114 Method::from_interpreted_offset(); 115 __ ldr(rscratch1,Address(method, entry_offset)); 116 __ br(rscratch1); 117 __ bind(L_no_such_method); 118 __ far_jump(RuntimeAddress(StubRoutines::throw_AbstractMethodError_entry())); 119} 120 121void MethodHandles::jump_to_lambda_form(MacroAssembler* _masm, 122 Register recv, Register method_temp, 123 Register temp2, 124 bool for_compiler_entry) { 125 BLOCK_COMMENT("jump_to_lambda_form {"); 126 // This is the initial entry point of a lazy method handle. 127 // After type checking, it picks up the invoker from the LambdaForm. 128 assert_different_registers(recv, method_temp, temp2); 129 assert(recv != noreg, "required register"); 130 assert(method_temp == rmethod, "required register for loading method"); 131 132 //NOT_PRODUCT({ FlagSetting fs(TraceMethodHandles, true); trace_method_handle(_masm, "LZMH"); }); 133 134 // Load the invoker, as MH -> MH.form -> LF.vmentry 135 __ verify_oop(recv); 136 __ load_heap_oop(method_temp, Address(recv, NONZERO(java_lang_invoke_MethodHandle::form_offset_in_bytes()))); 137 __ verify_oop(method_temp); 138 __ load_heap_oop(method_temp, Address(method_temp, NONZERO(java_lang_invoke_LambdaForm::vmentry_offset_in_bytes()))); 139 __ verify_oop(method_temp); 140 // the following assumes that a Method* is normally compressed in the vmtarget field: 141 __ ldr(method_temp, Address(method_temp, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes()))); 142 143 if (VerifyMethodHandles && !for_compiler_entry) { 144 // make sure recv is already on stack 145 __ ldr(temp2, Address(method_temp, Method::const_offset())); 146 __ load_sized_value(temp2, 147 Address(temp2, ConstMethod::size_of_parameters_offset()), 148 sizeof(u2), /*is_signed*/ false); 149 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 150 Label L; 151 __ ldr(rscratch1, __ argument_address(temp2, -1)); 152 __ cmp(recv, rscratch1); 153 __ br(Assembler::EQ, L); 154 __ ldr(r0, __ argument_address(temp2, -1)); 155 __ hlt(0); 156 __ BIND(L); 157 } 158 159 jump_from_method_handle(_masm, method_temp, temp2, for_compiler_entry); 160 BLOCK_COMMENT("} jump_to_lambda_form"); 161} 162 163// Code generation 164address MethodHandles::generate_method_handle_interpreter_entry(MacroAssembler* _masm, 165 vmIntrinsics::ID iid) { 166 const bool not_for_compiler_entry = false; // this is the interpreter entry 167 assert(is_signature_polymorphic(iid), "expected invoke iid"); 168 if (iid == vmIntrinsics::_invokeGeneric || 169 iid == vmIntrinsics::_compiledLambdaForm) { 170 // Perhaps surprisingly, the symbolic references visible to Java are not directly used. 171 // They are linked to Java-generated adapters via MethodHandleNatives.linkMethod. 172 // They all allow an appendix argument. 173 __ hlt(0); // empty stubs make SG sick 174 return NULL; 175 } 176 177 // r13: sender SP (must preserve; see prepare_to_jump_from_interpreted) 178 // rmethod: Method* 179 // r3: argument locator (parameter slot count, added to rsp) 180 // r1: used as temp to hold mh or receiver 181 // r0, r11: garbage temps, blown away 182 Register argp = r3; // argument list ptr, live on error paths 183 Register temp = r0; 184 Register mh = r1; // MH receiver; dies quickly and is recycled 185 186 // here's where control starts out: 187 __ align(CodeEntryAlignment); 188 address entry_point = __ pc(); 189 190 if (VerifyMethodHandles) { 191 assert(Method::intrinsic_id_size_in_bytes() == 2, "assuming Method::_intrinsic_id is u2"); 192 193 Label L; 194 BLOCK_COMMENT("verify_intrinsic_id {"); 195 __ ldrh(rscratch1, Address(rmethod, Method::intrinsic_id_offset_in_bytes())); 196 __ cmp(rscratch1, (int) iid); 197 __ br(Assembler::EQ, L); 198 if (iid == vmIntrinsics::_linkToVirtual || 199 iid == vmIntrinsics::_linkToSpecial) { 200 // could do this for all kinds, but would explode assembly code size 201 trace_method_handle(_masm, "bad Method*::intrinsic_id"); 202 } 203 __ hlt(0); 204 __ bind(L); 205 BLOCK_COMMENT("} verify_intrinsic_id"); 206 } 207 208 // First task: Find out how big the argument list is. 209 Address r3_first_arg_addr; 210 int ref_kind = signature_polymorphic_intrinsic_ref_kind(iid); 211 assert(ref_kind != 0 || iid == vmIntrinsics::_invokeBasic, "must be _invokeBasic or a linkTo intrinsic"); 212 if (ref_kind == 0 || MethodHandles::ref_kind_has_receiver(ref_kind)) { 213 __ ldr(argp, Address(rmethod, Method::const_offset())); 214 __ load_sized_value(argp, 215 Address(argp, ConstMethod::size_of_parameters_offset()), 216 sizeof(u2), /*is_signed*/ false); 217 // assert(sizeof(u2) == sizeof(Method::_size_of_parameters), ""); 218 r3_first_arg_addr = __ argument_address(argp, -1); 219 } else { 220 DEBUG_ONLY(argp = noreg); 221 } 222 223 if (!is_signature_polymorphic_static(iid)) { 224 __ ldr(mh, r3_first_arg_addr); 225 DEBUG_ONLY(argp = noreg); 226 } 227 228 // r3_first_arg_addr is live! 229 230 trace_method_handle_interpreter_entry(_masm, iid); 231 if (iid == vmIntrinsics::_invokeBasic) { 232 generate_method_handle_dispatch(_masm, iid, mh, noreg, not_for_compiler_entry); 233 234 } else { 235 // Adjust argument list by popping the trailing MemberName argument. 236 Register recv = noreg; 237 if (MethodHandles::ref_kind_has_receiver(ref_kind)) { 238 // Load the receiver (not the MH; the actual MemberName's receiver) up from the interpreter stack. 239 __ ldr(recv = r2, r3_first_arg_addr); 240 } 241 DEBUG_ONLY(argp = noreg); 242 Register rmember = rmethod; // MemberName ptr; incoming method ptr is dead now 243 __ pop(rmember); // extract last argument 244 generate_method_handle_dispatch(_masm, iid, recv, rmember, not_for_compiler_entry); 245 } 246 247 return entry_point; 248} 249 250 251void MethodHandles::generate_method_handle_dispatch(MacroAssembler* _masm, 252 vmIntrinsics::ID iid, 253 Register receiver_reg, 254 Register member_reg, 255 bool for_compiler_entry) { 256 assert(is_signature_polymorphic(iid), "expected invoke iid"); 257 // temps used in this code are not used in *either* compiled or interpreted calling sequences 258 Register temp1 = r10; 259 Register temp2 = r11; 260 Register temp3 = r14; // r13 is live by this point: it contains the sender SP 261 if (for_compiler_entry) { 262 assert(receiver_reg == (iid == vmIntrinsics::_linkToStatic ? noreg : j_rarg0), "only valid assignment"); 263 assert_different_registers(temp1, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7); 264 assert_different_registers(temp2, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7); 265 assert_different_registers(temp3, j_rarg0, j_rarg1, j_rarg2, j_rarg3, j_rarg4, j_rarg5, j_rarg6, j_rarg7); 266 } 267 268 assert_different_registers(temp1, temp2, temp3, receiver_reg); 269 assert_different_registers(temp1, temp2, temp3, member_reg); 270 271 if (iid == vmIntrinsics::_invokeBasic) { 272 // indirect through MH.form.vmentry.vmtarget 273 jump_to_lambda_form(_masm, receiver_reg, rmethod, temp1, for_compiler_entry); 274 275 } else { 276 // The method is a member invoker used by direct method handles. 277 if (VerifyMethodHandles) { 278 // make sure the trailing argument really is a MemberName (caller responsibility) 279 verify_klass(_masm, member_reg, SystemDictionary::WK_KLASS_ENUM_NAME(java_lang_invoke_MemberName), 280 "MemberName required for invokeVirtual etc."); 281 } 282 283 Address member_clazz( member_reg, NONZERO(java_lang_invoke_MemberName::clazz_offset_in_bytes())); 284 Address member_vmindex( member_reg, NONZERO(java_lang_invoke_MemberName::vmindex_offset_in_bytes())); 285 Address member_vmtarget( member_reg, NONZERO(java_lang_invoke_MemberName::vmtarget_offset_in_bytes())); 286 287 Register temp1_recv_klass = temp1; 288 if (iid != vmIntrinsics::_linkToStatic) { 289 __ verify_oop(receiver_reg); 290 if (iid == vmIntrinsics::_linkToSpecial) { 291 // Don't actually load the klass; just null-check the receiver. 292 __ null_check(receiver_reg); 293 } else { 294 // load receiver klass itself 295 __ null_check(receiver_reg, oopDesc::klass_offset_in_bytes()); 296 __ load_klass(temp1_recv_klass, receiver_reg); 297 __ verify_klass_ptr(temp1_recv_klass); 298 } 299 BLOCK_COMMENT("check_receiver {"); 300 // The receiver for the MemberName must be in receiver_reg. 301 // Check the receiver against the MemberName.clazz 302 if (VerifyMethodHandles && iid == vmIntrinsics::_linkToSpecial) { 303 // Did not load it above... 304 __ load_klass(temp1_recv_klass, receiver_reg); 305 __ verify_klass_ptr(temp1_recv_klass); 306 } 307 if (VerifyMethodHandles && iid != vmIntrinsics::_linkToInterface) { 308 Label L_ok; 309 Register temp2_defc = temp2; 310 __ load_heap_oop(temp2_defc, member_clazz); 311 load_klass_from_Class(_masm, temp2_defc); 312 __ verify_klass_ptr(temp2_defc); 313 __ check_klass_subtype(temp1_recv_klass, temp2_defc, temp3, L_ok); 314 // If we get here, the type check failed! 315 __ hlt(0); 316 // __ STOP("receiver class disagrees with MemberName.clazz"); 317 __ bind(L_ok); 318 } 319 BLOCK_COMMENT("} check_receiver"); 320 } 321 if (iid == vmIntrinsics::_linkToSpecial || 322 iid == vmIntrinsics::_linkToStatic) { 323 DEBUG_ONLY(temp1_recv_klass = noreg); // these guys didn't load the recv_klass 324 } 325 326 // Live registers at this point: 327 // member_reg - MemberName that was the trailing argument 328 // temp1_recv_klass - klass of stacked receiver, if needed 329 // r13 - interpreter linkage (if interpreted) ??? FIXME 330 // r1 ... r0 - compiler arguments (if compiled) 331 332 Label L_incompatible_class_change_error; 333 switch (iid) { 334 case vmIntrinsics::_linkToSpecial: 335 if (VerifyMethodHandles) { 336 verify_ref_kind(_masm, JVM_REF_invokeSpecial, member_reg, temp3); 337 } 338 __ ldr(rmethod, member_vmtarget); 339 break; 340 341 case vmIntrinsics::_linkToStatic: 342 if (VerifyMethodHandles) { 343 verify_ref_kind(_masm, JVM_REF_invokeStatic, member_reg, temp3); 344 } 345 __ ldr(rmethod, member_vmtarget); 346 break; 347 348 case vmIntrinsics::_linkToVirtual: 349 { 350 // same as TemplateTable::invokevirtual, 351 // minus the CP setup and profiling: 352 353 if (VerifyMethodHandles) { 354 verify_ref_kind(_masm, JVM_REF_invokeVirtual, member_reg, temp3); 355 } 356 357 // pick out the vtable index from the MemberName, and then we can discard it: 358 Register temp2_index = temp2; 359 __ ldr(temp2_index, member_vmindex); 360 361 if (VerifyMethodHandles) { 362 Label L_index_ok; 363 __ cmpw(temp2_index, 0U); 364 __ br(Assembler::GE, L_index_ok); 365 __ hlt(0); 366 __ BIND(L_index_ok); 367 } 368 369 // Note: The verifier invariants allow us to ignore MemberName.clazz and vmtarget 370 // at this point. And VerifyMethodHandles has already checked clazz, if needed. 371 372 // get target Method* & entry point 373 __ lookup_virtual_method(temp1_recv_klass, temp2_index, rmethod); 374 break; 375 } 376 377 case vmIntrinsics::_linkToInterface: 378 { 379 // same as TemplateTable::invokeinterface 380 // (minus the CP setup and profiling, with different argument motion) 381 if (VerifyMethodHandles) { 382 verify_ref_kind(_masm, JVM_REF_invokeInterface, member_reg, temp3); 383 } 384 385 Register temp3_intf = temp3; 386 __ load_heap_oop(temp3_intf, member_clazz); 387 load_klass_from_Class(_masm, temp3_intf); 388 __ verify_klass_ptr(temp3_intf); 389 390 Register rindex = rmethod; 391 __ ldr(rindex, member_vmindex); 392 if (VerifyMethodHandles) { 393 Label L; 394 __ cmpw(rindex, 0U); 395 __ br(Assembler::GE, L); 396 __ hlt(0); 397 __ bind(L); 398 } 399 400 // given intf, index, and recv klass, dispatch to the implementation method 401 __ lookup_interface_method(temp1_recv_klass, temp3_intf, 402 // note: next two args must be the same: 403 rindex, rmethod, 404 temp2, 405 L_incompatible_class_change_error); 406 break; 407 } 408 409 default: 410 fatal("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid)); 411 break; 412 } 413 414 // live at this point: rmethod, r13 (if interpreted) 415 416 // After figuring out which concrete method to call, jump into it. 417 // Note that this works in the interpreter with no data motion. 418 // But the compiled version will require that r2_recv be shifted out. 419 __ verify_method_ptr(rmethod); 420 jump_from_method_handle(_masm, rmethod, temp1, for_compiler_entry); 421 if (iid == vmIntrinsics::_linkToInterface) { 422 __ bind(L_incompatible_class_change_error); 423 __ far_jump(RuntimeAddress(StubRoutines::throw_IncompatibleClassChangeError_entry())); 424 } 425 } 426} 427 428#ifndef PRODUCT 429void trace_method_handle_stub(const char* adaptername, 430 oop mh, 431 intptr_t* saved_regs, 432 intptr_t* entry_sp) { } 433 434// The stub wraps the arguments in a struct on the stack to avoid 435// dealing with the different calling conventions for passing 6 436// arguments. 437struct MethodHandleStubArguments { 438 const char* adaptername; 439 oopDesc* mh; 440 intptr_t* saved_regs; 441 intptr_t* entry_sp; 442}; 443void trace_method_handle_stub_wrapper(MethodHandleStubArguments* args) { } 444 445void MethodHandles::trace_method_handle(MacroAssembler* _masm, const char* adaptername) { } 446#endif //PRODUCT 447