1 /* 2 * Copyright (c) 1999, 2015, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #include "precompiled.hpp" 26 #include "c1/c1_MacroAssembler.hpp" 27 #include "c1/c1_Runtime1.hpp" 28 #include "classfile/systemDictionary.hpp" 29 #include "gc/shared/collectedHeap.hpp" 30 #include "interpreter/interpreter.hpp" 31 #include "oops/arrayOop.hpp" 32 #include "oops/markOop.hpp" 33 #include "runtime/basicLock.hpp" 34 #include "runtime/biasedLocking.hpp" 35 #include "runtime/os.hpp" 36 #include "runtime/sharedRuntime.hpp" 37 #include "runtime/stubRoutines.hpp" 38 39 void C1_MacroAssembler::inline_cache_check(Register receiver, Register iCache) { 40 Label L; 41 const Register temp_reg = G3_scratch; 42 // Note: needs more testing of out-of-line vs. inline slow case 43 verify_oop(receiver); 44 load_klass(receiver, temp_reg); 45 cmp_and_brx_short(temp_reg, iCache, Assembler::equal, Assembler::pt, L); 46 AddressLiteral ic_miss(SharedRuntime::get_ic_miss_stub()); 47 jump_to(ic_miss, temp_reg); 48 delayed()->nop(); 49 align(CodeEntryAlignment); 50 bind(L); 51 } 52 53 54 void C1_MacroAssembler::explicit_null_check(Register base) { 55 Unimplemented(); 56 } 57 58 59 void C1_MacroAssembler::build_frame(int frame_size_in_bytes, int bang_size_in_bytes) { 60 assert(bang_size_in_bytes >= frame_size_in_bytes, "stack bang size incorrect"); 61 generate_stack_overflow_check(bang_size_in_bytes); 62 // Create the frame. 63 save_frame_c1(frame_size_in_bytes); 64 } 65 66 67 void C1_MacroAssembler::unverified_entry(Register receiver, Register ic_klass) { 68 if (C1Breakpoint) breakpoint_trap(); 69 inline_cache_check(receiver, ic_klass); 70 } 71 72 73 void C1_MacroAssembler::verified_entry() { 74 if (C1Breakpoint) breakpoint_trap(); 75 // build frame 76 verify_FPU(0, "method_entry"); 77 } 78 79 80 void C1_MacroAssembler::lock_object(Register Rmark, Register Roop, Register Rbox, Register Rscratch, Label& slow_case) { 81 assert_different_registers(Rmark, Roop, Rbox, Rscratch); 82 83 Label done; 84 85 Address mark_addr(Roop, oopDesc::mark_offset_in_bytes()); 86 87 // The following move must be the first instruction of emitted since debug 88 // information may be generated for it. 89 // Load object header 90 ld_ptr(mark_addr, Rmark); 91 92 verify_oop(Roop); 93 94 // save object being locked into the BasicObjectLock 95 st_ptr(Roop, Rbox, BasicObjectLock::obj_offset_in_bytes()); 96 97 if (UseBiasedLocking) { 98 biased_locking_enter(Roop, Rmark, Rscratch, done, &slow_case); 99 } 100 101 // Save Rbox in Rscratch to be used for the cas operation 102 mov(Rbox, Rscratch); 103 104 // and mark it unlocked 105 or3(Rmark, markOopDesc::unlocked_value, Rmark); 106 107 // save unlocked object header into the displaced header location on the stack 108 st_ptr(Rmark, Rbox, BasicLock::displaced_header_offset_in_bytes()); 109 110 // compare object markOop with Rmark and if equal exchange Rscratch with object markOop 111 assert(mark_addr.disp() == 0, "cas must take a zero displacement"); 112 cas_ptr(mark_addr.base(), Rmark, Rscratch); 113 // if compare/exchange succeeded we found an unlocked object and we now have locked it 114 // hence we are done 115 cmp(Rmark, Rscratch); 116 brx(Assembler::equal, false, Assembler::pt, done); 117 delayed()->sub(Rscratch, SP, Rscratch); //pull next instruction into delay slot 118 // we did not find an unlocked object so see if this is a recursive case 119 // sub(Rscratch, SP, Rscratch); 120 assert(os::vm_page_size() > 0xfff, "page size too small - change the constant"); 121 andcc(Rscratch, 0xfffff003, Rscratch); 122 brx(Assembler::notZero, false, Assembler::pn, slow_case); 123 delayed()->st_ptr(Rscratch, Rbox, BasicLock::displaced_header_offset_in_bytes()); 124 bind(done); 125 } 126 127 128 void C1_MacroAssembler::unlock_object(Register Rmark, Register Roop, Register Rbox, Label& slow_case) { 129 assert_different_registers(Rmark, Roop, Rbox); 130 131 Label done; 132 133 Address mark_addr(Roop, oopDesc::mark_offset_in_bytes()); 134 assert(mark_addr.disp() == 0, "cas must take a zero displacement"); 135 136 if (UseBiasedLocking) { 137 // load the object out of the BasicObjectLock 138 ld_ptr(Rbox, BasicObjectLock::obj_offset_in_bytes(), Roop); 139 verify_oop(Roop); 140 biased_locking_exit(mark_addr, Rmark, done); 141 } 142 // Test first it it is a fast recursive unlock 143 ld_ptr(Rbox, BasicLock::displaced_header_offset_in_bytes(), Rmark); 144 br_null_short(Rmark, Assembler::pt, done); 145 if (!UseBiasedLocking) { 146 // load object 147 ld_ptr(Rbox, BasicObjectLock::obj_offset_in_bytes(), Roop); 148 verify_oop(Roop); 149 } 150 151 // Check if it is still a light weight lock, this is is true if we see 152 // the stack address of the basicLock in the markOop of the object 153 cas_ptr(mark_addr.base(), Rbox, Rmark); 154 cmp(Rbox, Rmark); 155 156 brx(Assembler::notEqual, false, Assembler::pn, slow_case); 157 delayed()->nop(); 158 // Done 159 bind(done); 160 } 161 162 163 void C1_MacroAssembler::try_allocate( 164 Register obj, // result: pointer to object after successful allocation 165 Register var_size_in_bytes, // object size in bytes if unknown at compile time; invalid otherwise 166 int con_size_in_bytes, // object size in bytes if known at compile time 167 Register t1, // temp register, must be global register for incr_allocated_bytes 168 Register t2, // temp register 169 Label& slow_case // continuation point if fast allocation fails 170 ) { 171 RegisterOrConstant size_in_bytes = var_size_in_bytes->is_valid() 172 ? RegisterOrConstant(var_size_in_bytes) : RegisterOrConstant(con_size_in_bytes); 173 if (UseTLAB) { 174 tlab_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, slow_case); 175 } else { 176 eden_allocate(obj, var_size_in_bytes, con_size_in_bytes, t1, t2, slow_case); 177 incr_allocated_bytes(size_in_bytes, t1, t2); 178 } 179 } 180 181 182 void C1_MacroAssembler::initialize_header(Register obj, Register klass, Register len, Register t1, Register t2) { 183 assert_different_registers(obj, klass, len, t1, t2); 184 if (UseBiasedLocking && !len->is_valid()) { 185 ld_ptr(klass, in_bytes(Klass::prototype_header_offset()), t1); 186 } else { 187 set((intx)markOopDesc::prototype(), t1); 188 } 189 st_ptr(t1, obj, oopDesc::mark_offset_in_bytes()); 190 if (UseCompressedClassPointers) { 191 // Save klass 192 mov(klass, t1); 193 encode_klass_not_null(t1); 194 stw(t1, obj, oopDesc::klass_offset_in_bytes()); 195 } else { 196 st_ptr(klass, obj, oopDesc::klass_offset_in_bytes()); 197 } 198 if (len->is_valid()) { 199 st(len, obj, arrayOopDesc::length_offset_in_bytes()); 200 } else if (UseCompressedClassPointers) { 201 // otherwise length is in the class gap 202 store_klass_gap(G0, obj); 203 } 204 } 205 206 207 void C1_MacroAssembler::initialize_body(Register base, Register index) { 208 assert_different_registers(base, index); 209 Label loop; 210 bind(loop); 211 subcc(index, HeapWordSize, index); 212 brx(Assembler::greaterEqual, true, Assembler::pt, loop); 213 delayed()->st_ptr(G0, base, index); 214 } 215 216 217 void C1_MacroAssembler::allocate_object( 218 Register obj, // result: pointer to object after successful allocation 219 Register t1, // temp register 220 Register t2, // temp register, must be a global register for try_allocate 221 Register t3, // temp register 222 int hdr_size, // object header size in words 223 int obj_size, // object size in words 224 Register klass, // object klass 225 Label& slow_case // continuation point if fast allocation fails 226 ) { 227 assert_different_registers(obj, t1, t2, t3, klass); 228 assert(klass == G5, "must be G5"); 229 230 // allocate space & initialize header 231 if (!is_simm13(obj_size * wordSize)) { 232 // would need to use extra register to load 233 // object size => go the slow case for now 234 ba(slow_case); 235 delayed()->nop(); 236 return; 237 } 238 try_allocate(obj, noreg, obj_size * wordSize, t2, t3, slow_case); 239 240 initialize_object(obj, klass, noreg, obj_size * HeapWordSize, t1, t2); 241 } 242 243 void C1_MacroAssembler::initialize_object( 244 Register obj, // result: pointer to object after successful allocation 245 Register klass, // object klass 246 Register var_size_in_bytes, // object size in bytes if unknown at compile time; invalid otherwise 247 int con_size_in_bytes, // object size in bytes if known at compile time 248 Register t1, // temp register 249 Register t2 // temp register 250 ) { 251 const int hdr_size_in_bytes = instanceOopDesc::header_size() * HeapWordSize; 252 253 initialize_header(obj, klass, noreg, t1, t2); 254 255 #ifdef ASSERT 256 { 257 Label ok; 258 ld(klass, in_bytes(Klass::layout_helper_offset()), t1); 259 if (var_size_in_bytes != noreg) { 260 cmp_and_brx_short(t1, var_size_in_bytes, Assembler::equal, Assembler::pt, ok); 261 } else { 262 cmp_and_brx_short(t1, con_size_in_bytes, Assembler::equal, Assembler::pt, ok); 263 } 264 stop("bad size in initialize_object"); 265 should_not_reach_here(); 266 267 bind(ok); 268 } 269 270 #endif 271 272 // initialize body 273 const int threshold = 5 * HeapWordSize; // approximate break even point for code size 274 if (var_size_in_bytes != noreg) { 275 // use a loop 276 add(obj, hdr_size_in_bytes, t1); // compute address of first element 277 sub(var_size_in_bytes, hdr_size_in_bytes, t2); // compute size of body 278 initialize_body(t1, t2); 279 #ifndef _LP64 280 } else if (con_size_in_bytes < threshold * 2) { 281 // on v9 we can do double word stores to fill twice as much space. 282 assert(hdr_size_in_bytes % 8 == 0, "double word aligned"); 283 assert(con_size_in_bytes % 8 == 0, "double word aligned"); 284 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += 2 * HeapWordSize) stx(G0, obj, i); 285 #endif 286 } else if (con_size_in_bytes <= threshold) { 287 // use explicit NULL stores 288 for (int i = hdr_size_in_bytes; i < con_size_in_bytes; i += HeapWordSize) st_ptr(G0, obj, i); 289 } else if (con_size_in_bytes > hdr_size_in_bytes) { 290 // use a loop 291 const Register base = t1; 292 const Register index = t2; 293 add(obj, hdr_size_in_bytes, base); // compute address of first element 294 // compute index = number of words to clear 295 set(con_size_in_bytes - hdr_size_in_bytes, index); 296 initialize_body(base, index); 297 } 298 299 if (CURRENT_ENV->dtrace_alloc_probes()) { 300 assert(obj == O0, "must be"); 301 call(CAST_FROM_FN_PTR(address, Runtime1::entry_for(Runtime1::dtrace_object_alloc_id)), 302 relocInfo::runtime_call_type); 303 delayed()->nop(); 304 } 305 306 verify_oop(obj); 307 } 308 309 310 void C1_MacroAssembler::allocate_array( 311 Register obj, // result: pointer to array after successful allocation 312 Register len, // array length 313 Register t1, // temp register 314 Register t2, // temp register 315 Register t3, // temp register 316 int hdr_size, // object header size in words 317 int elt_size, // element size in bytes 318 Register klass, // object klass 319 Label& slow_case // continuation point if fast allocation fails 320 ) { 321 assert_different_registers(obj, len, t1, t2, t3, klass); 322 assert(klass == G5, "must be G5"); 323 assert(t1 == G1, "must be G1"); 324 325 // determine alignment mask 326 assert(!(BytesPerWord & 1), "must be a multiple of 2 for masking code to work"); 327 328 // check for negative or excessive length 329 // note: the maximum length allowed is chosen so that arrays of any 330 // element size with this length are always smaller or equal 331 // to the largest integer (i.e., array size computation will 332 // not overflow) 333 set(max_array_allocation_length, t1); 334 cmp(len, t1); 335 br(Assembler::greaterUnsigned, false, Assembler::pn, slow_case); 336 337 // compute array size 338 // note: if 0 <= len <= max_length, len*elt_size + header + alignment is 339 // smaller or equal to the largest integer; also, since top is always 340 // aligned, we can do the alignment here instead of at the end address 341 // computation 342 const Register arr_size = t1; 343 switch (elt_size) { 344 case 1: delayed()->mov(len, arr_size); break; 345 case 2: delayed()->sll(len, 1, arr_size); break; 346 case 4: delayed()->sll(len, 2, arr_size); break; 347 case 8: delayed()->sll(len, 3, arr_size); break; 348 default: ShouldNotReachHere(); 349 } 350 add(arr_size, hdr_size * wordSize + MinObjAlignmentInBytesMask, arr_size); // add space for header & alignment 351 and3(arr_size, ~MinObjAlignmentInBytesMask, arr_size); // align array size 352 353 // allocate space & initialize header 354 if (UseTLAB) { 355 tlab_allocate(obj, arr_size, 0, t2, slow_case); 356 } else { 357 eden_allocate(obj, arr_size, 0, t2, t3, slow_case); 358 } 359 initialize_header(obj, klass, len, t2, t3); 360 361 // initialize body 362 const Register base = t2; 363 const Register index = t3; 364 add(obj, hdr_size * wordSize, base); // compute address of first element 365 sub(arr_size, hdr_size * wordSize, index); // compute index = number of words to clear 366 initialize_body(base, index); 367 368 if (CURRENT_ENV->dtrace_alloc_probes()) { 369 assert(obj == O0, "must be"); 370 call(CAST_FROM_FN_PTR(address, Runtime1::entry_for(Runtime1::dtrace_object_alloc_id)), 371 relocInfo::runtime_call_type); 372 delayed()->nop(); 373 } 374 375 verify_oop(obj); 376 } 377 378 379 #ifndef PRODUCT 380 381 void C1_MacroAssembler::verify_stack_oop(int stack_offset) { 382 if (!VerifyOops) return; 383 verify_oop_addr(Address(SP, stack_offset + STACK_BIAS)); 384 } 385 386 void C1_MacroAssembler::verify_not_null_oop(Register r) { 387 Label not_null; 388 br_notnull_short(r, Assembler::pt, not_null); 389 stop("non-null oop required"); 390 bind(not_null); 391 if (!VerifyOops) return; 392 verify_oop(r); 393 } 394 395 void C1_MacroAssembler::invalidate_registers(bool iregisters, bool lregisters, bool oregisters, 396 Register preserve1, Register preserve2) { 397 if (iregisters) { 398 for (int i = 0; i < 6; i++) { 399 Register r = as_iRegister(i); 400 if (r != preserve1 && r != preserve2) set(0xdead, r); 401 } 402 } 403 if (oregisters) { 404 for (int i = 0; i < 6; i++) { 405 Register r = as_oRegister(i); 406 if (r != preserve1 && r != preserve2) set(0xdead, r); 407 } 408 } 409 if (lregisters) { 410 for (int i = 0; i < 8; i++) { 411 Register r = as_lRegister(i); 412 if (r != preserve1 && r != preserve2) set(0xdead, r); 413 } 414 } 415 } 416 417 418 #endif