vm_version_x86.cpp revision 9814:22fd02fad88b
1/* 2 * Copyright (c) 1997, 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 "asm/macroAssembler.hpp" 27#include "asm/macroAssembler.inline.hpp" 28#include "memory/resourceArea.hpp" 29#include "runtime/java.hpp" 30#include "runtime/os.hpp" 31#include "runtime/stubCodeGenerator.hpp" 32#include "vm_version_x86.hpp" 33 34 35int VM_Version::_cpu; 36int VM_Version::_model; 37int VM_Version::_stepping; 38VM_Version::CpuidInfo VM_Version::_cpuid_info = { 0, }; 39 40// Address of instruction which causes SEGV 41address VM_Version::_cpuinfo_segv_addr = 0; 42// Address of instruction after the one which causes SEGV 43address VM_Version::_cpuinfo_cont_addr = 0; 44 45static BufferBlob* stub_blob; 46static const int stub_size = 1000; 47 48extern "C" { 49 typedef void (*get_cpu_info_stub_t)(void*); 50} 51static get_cpu_info_stub_t get_cpu_info_stub = NULL; 52 53 54class VM_Version_StubGenerator: public StubCodeGenerator { 55 public: 56 57 VM_Version_StubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {} 58 59 address generate_get_cpu_info() { 60 // Flags to test CPU type. 61 const uint32_t HS_EFL_AC = 0x40000; 62 const uint32_t HS_EFL_ID = 0x200000; 63 // Values for when we don't have a CPUID instruction. 64 const int CPU_FAMILY_SHIFT = 8; 65 const uint32_t CPU_FAMILY_386 = (3 << CPU_FAMILY_SHIFT); 66 const uint32_t CPU_FAMILY_486 = (4 << CPU_FAMILY_SHIFT); 67 68 Label detect_486, cpu486, detect_586, std_cpuid1, std_cpuid4; 69 Label sef_cpuid, ext_cpuid, ext_cpuid1, ext_cpuid5, ext_cpuid7, done, wrapup; 70 Label legacy_setup, save_restore_except, legacy_save_restore, start_simd_check; 71 72 StubCodeMark mark(this, "VM_Version", "get_cpu_info_stub"); 73# define __ _masm-> 74 75 address start = __ pc(); 76 77 // 78 // void get_cpu_info(VM_Version::CpuidInfo* cpuid_info); 79 // 80 // LP64: rcx and rdx are first and second argument registers on windows 81 82 __ push(rbp); 83#ifdef _LP64 84 __ mov(rbp, c_rarg0); // cpuid_info address 85#else 86 __ movptr(rbp, Address(rsp, 8)); // cpuid_info address 87#endif 88 __ push(rbx); 89 __ push(rsi); 90 __ pushf(); // preserve rbx, and flags 91 __ pop(rax); 92 __ push(rax); 93 __ mov(rcx, rax); 94 // 95 // if we are unable to change the AC flag, we have a 386 96 // 97 __ xorl(rax, HS_EFL_AC); 98 __ push(rax); 99 __ popf(); 100 __ pushf(); 101 __ pop(rax); 102 __ cmpptr(rax, rcx); 103 __ jccb(Assembler::notEqual, detect_486); 104 105 __ movl(rax, CPU_FAMILY_386); 106 __ movl(Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())), rax); 107 __ jmp(done); 108 109 // 110 // If we are unable to change the ID flag, we have a 486 which does 111 // not support the "cpuid" instruction. 112 // 113 __ bind(detect_486); 114 __ mov(rax, rcx); 115 __ xorl(rax, HS_EFL_ID); 116 __ push(rax); 117 __ popf(); 118 __ pushf(); 119 __ pop(rax); 120 __ cmpptr(rcx, rax); 121 __ jccb(Assembler::notEqual, detect_586); 122 123 __ bind(cpu486); 124 __ movl(rax, CPU_FAMILY_486); 125 __ movl(Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())), rax); 126 __ jmp(done); 127 128 // 129 // At this point, we have a chip which supports the "cpuid" instruction 130 // 131 __ bind(detect_586); 132 __ xorl(rax, rax); 133 __ cpuid(); 134 __ orl(rax, rax); 135 __ jcc(Assembler::equal, cpu486); // if cpuid doesn't support an input 136 // value of at least 1, we give up and 137 // assume a 486 138 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset()))); 139 __ movl(Address(rsi, 0), rax); 140 __ movl(Address(rsi, 4), rbx); 141 __ movl(Address(rsi, 8), rcx); 142 __ movl(Address(rsi,12), rdx); 143 144 __ cmpl(rax, 0xa); // Is cpuid(0xB) supported? 145 __ jccb(Assembler::belowEqual, std_cpuid4); 146 147 // 148 // cpuid(0xB) Processor Topology 149 // 150 __ movl(rax, 0xb); 151 __ xorl(rcx, rcx); // Threads level 152 __ cpuid(); 153 154 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB0_offset()))); 155 __ movl(Address(rsi, 0), rax); 156 __ movl(Address(rsi, 4), rbx); 157 __ movl(Address(rsi, 8), rcx); 158 __ movl(Address(rsi,12), rdx); 159 160 __ movl(rax, 0xb); 161 __ movl(rcx, 1); // Cores level 162 __ cpuid(); 163 __ push(rax); 164 __ andl(rax, 0x1f); // Determine if valid topology level 165 __ orl(rax, rbx); // eax[4:0] | ebx[0:15] == 0 indicates invalid level 166 __ andl(rax, 0xffff); 167 __ pop(rax); 168 __ jccb(Assembler::equal, std_cpuid4); 169 170 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB1_offset()))); 171 __ movl(Address(rsi, 0), rax); 172 __ movl(Address(rsi, 4), rbx); 173 __ movl(Address(rsi, 8), rcx); 174 __ movl(Address(rsi,12), rdx); 175 176 __ movl(rax, 0xb); 177 __ movl(rcx, 2); // Packages level 178 __ cpuid(); 179 __ push(rax); 180 __ andl(rax, 0x1f); // Determine if valid topology level 181 __ orl(rax, rbx); // eax[4:0] | ebx[0:15] == 0 indicates invalid level 182 __ andl(rax, 0xffff); 183 __ pop(rax); 184 __ jccb(Assembler::equal, std_cpuid4); 185 186 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB2_offset()))); 187 __ movl(Address(rsi, 0), rax); 188 __ movl(Address(rsi, 4), rbx); 189 __ movl(Address(rsi, 8), rcx); 190 __ movl(Address(rsi,12), rdx); 191 192 // 193 // cpuid(0x4) Deterministic cache params 194 // 195 __ bind(std_cpuid4); 196 __ movl(rax, 4); 197 __ cmpl(rax, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset()))); // Is cpuid(0x4) supported? 198 __ jccb(Assembler::greater, std_cpuid1); 199 200 __ xorl(rcx, rcx); // L1 cache 201 __ cpuid(); 202 __ push(rax); 203 __ andl(rax, 0x1f); // Determine if valid cache parameters used 204 __ orl(rax, rax); // eax[4:0] == 0 indicates invalid cache 205 __ pop(rax); 206 __ jccb(Assembler::equal, std_cpuid1); 207 208 __ lea(rsi, Address(rbp, in_bytes(VM_Version::dcp_cpuid4_offset()))); 209 __ movl(Address(rsi, 0), rax); 210 __ movl(Address(rsi, 4), rbx); 211 __ movl(Address(rsi, 8), rcx); 212 __ movl(Address(rsi,12), rdx); 213 214 // 215 // Standard cpuid(0x1) 216 // 217 __ bind(std_cpuid1); 218 __ movl(rax, 1); 219 __ cpuid(); 220 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset()))); 221 __ movl(Address(rsi, 0), rax); 222 __ movl(Address(rsi, 4), rbx); 223 __ movl(Address(rsi, 8), rcx); 224 __ movl(Address(rsi,12), rdx); 225 226 // 227 // Check if OS has enabled XGETBV instruction to access XCR0 228 // (OSXSAVE feature flag) and CPU supports AVX 229 // 230 __ andl(rcx, 0x18000000); // cpuid1 bits osxsave | avx 231 __ cmpl(rcx, 0x18000000); 232 __ jccb(Assembler::notEqual, sef_cpuid); // jump if AVX is not supported 233 234 // 235 // XCR0, XFEATURE_ENABLED_MASK register 236 // 237 __ xorl(rcx, rcx); // zero for XCR0 register 238 __ xgetbv(); 239 __ lea(rsi, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); 240 __ movl(Address(rsi, 0), rax); 241 __ movl(Address(rsi, 4), rdx); 242 243 // 244 // cpuid(0x7) Structured Extended Features 245 // 246 __ bind(sef_cpuid); 247 __ movl(rax, 7); 248 __ cmpl(rax, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset()))); // Is cpuid(0x7) supported? 249 __ jccb(Assembler::greater, ext_cpuid); 250 251 __ xorl(rcx, rcx); 252 __ cpuid(); 253 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset()))); 254 __ movl(Address(rsi, 0), rax); 255 __ movl(Address(rsi, 4), rbx); 256 257 // 258 // Extended cpuid(0x80000000) 259 // 260 __ bind(ext_cpuid); 261 __ movl(rax, 0x80000000); 262 __ cpuid(); 263 __ cmpl(rax, 0x80000000); // Is cpuid(0x80000001) supported? 264 __ jcc(Assembler::belowEqual, done); 265 __ cmpl(rax, 0x80000004); // Is cpuid(0x80000005) supported? 266 __ jccb(Assembler::belowEqual, ext_cpuid1); 267 __ cmpl(rax, 0x80000006); // Is cpuid(0x80000007) supported? 268 __ jccb(Assembler::belowEqual, ext_cpuid5); 269 __ cmpl(rax, 0x80000007); // Is cpuid(0x80000008) supported? 270 __ jccb(Assembler::belowEqual, ext_cpuid7); 271 // 272 // Extended cpuid(0x80000008) 273 // 274 __ movl(rax, 0x80000008); 275 __ cpuid(); 276 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid8_offset()))); 277 __ movl(Address(rsi, 0), rax); 278 __ movl(Address(rsi, 4), rbx); 279 __ movl(Address(rsi, 8), rcx); 280 __ movl(Address(rsi,12), rdx); 281 282 // 283 // Extended cpuid(0x80000007) 284 // 285 __ bind(ext_cpuid7); 286 __ movl(rax, 0x80000007); 287 __ cpuid(); 288 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid7_offset()))); 289 __ movl(Address(rsi, 0), rax); 290 __ movl(Address(rsi, 4), rbx); 291 __ movl(Address(rsi, 8), rcx); 292 __ movl(Address(rsi,12), rdx); 293 294 // 295 // Extended cpuid(0x80000005) 296 // 297 __ bind(ext_cpuid5); 298 __ movl(rax, 0x80000005); 299 __ cpuid(); 300 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid5_offset()))); 301 __ movl(Address(rsi, 0), rax); 302 __ movl(Address(rsi, 4), rbx); 303 __ movl(Address(rsi, 8), rcx); 304 __ movl(Address(rsi,12), rdx); 305 306 // 307 // Extended cpuid(0x80000001) 308 // 309 __ bind(ext_cpuid1); 310 __ movl(rax, 0x80000001); 311 __ cpuid(); 312 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid1_offset()))); 313 __ movl(Address(rsi, 0), rax); 314 __ movl(Address(rsi, 4), rbx); 315 __ movl(Address(rsi, 8), rcx); 316 __ movl(Address(rsi,12), rdx); 317 318 // 319 // Check if OS has enabled XGETBV instruction to access XCR0 320 // (OSXSAVE feature flag) and CPU supports AVX 321 // 322 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset()))); 323 __ movl(rcx, 0x18000000); // cpuid1 bits osxsave | avx 324 __ andl(rcx, Address(rsi, 8)); // cpuid1 bits osxsave | avx 325 __ cmpl(rcx, 0x18000000); 326 __ jccb(Assembler::notEqual, done); // jump if AVX is not supported 327 328 __ movl(rax, 0x6); 329 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm 330 __ cmpl(rax, 0x6); 331 __ jccb(Assembler::equal, start_simd_check); // return if AVX is not supported 332 333 // we need to bridge farther than imm8, so we use this island as a thunk 334 __ bind(done); 335 __ jmp(wrapup); 336 337 __ bind(start_simd_check); 338 // 339 // Some OSs have a bug when upper 128/256bits of YMM/ZMM 340 // registers are not restored after a signal processing. 341 // Generate SEGV here (reference through NULL) 342 // and check upper YMM/ZMM bits after it. 343 // 344 intx saved_useavx = UseAVX; 345 intx saved_usesse = UseSSE; 346 // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f 347 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset()))); 348 __ movl(rax, 0x10000); 349 __ andl(rax, Address(rsi, 4)); // xcr0 bits sse | ymm 350 __ cmpl(rax, 0x10000); 351 __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported 352 // check _cpuid_info.xem_xcr0_eax.bits.opmask 353 // check _cpuid_info.xem_xcr0_eax.bits.zmm512 354 // check _cpuid_info.xem_xcr0_eax.bits.zmm32 355 __ movl(rax, 0xE0); 356 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm 357 __ cmpl(rax, 0xE0); 358 __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported 359 360 // EVEX setup: run in lowest evex mode 361 VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts 362 UseAVX = 3; 363 UseSSE = 2; 364 // load value into all 64 bytes of zmm7 register 365 __ movl(rcx, VM_Version::ymm_test_value()); 366 __ movdl(xmm0, rcx); 367 __ movl(rcx, 0xffff); 368 __ kmovwl(k1, rcx); 369 __ evpbroadcastd(xmm0, xmm0, Assembler::AVX_512bit); 370 __ evmovdqul(xmm7, xmm0, Assembler::AVX_512bit); 371#ifdef _LP64 372 __ evmovdqul(xmm8, xmm0, Assembler::AVX_512bit); 373 __ evmovdqul(xmm31, xmm0, Assembler::AVX_512bit); 374#endif 375 VM_Version::clean_cpuFeatures(); 376 __ jmp(save_restore_except); 377 378 __ bind(legacy_setup); 379 // AVX setup 380 VM_Version::set_avx_cpuFeatures(); // Enable temporary to pass asserts 381 UseAVX = 1; 382 UseSSE = 2; 383 // load value into all 32 bytes of ymm7 register 384 __ movl(rcx, VM_Version::ymm_test_value()); 385 386 __ movdl(xmm0, rcx); 387 __ pshufd(xmm0, xmm0, 0x00); 388 __ vinsertf128h(xmm0, xmm0, xmm0); 389 __ vmovdqu(xmm7, xmm0); 390#ifdef _LP64 391 __ vmovdqu(xmm8, xmm0); 392 __ vmovdqu(xmm15, xmm0); 393#endif 394 VM_Version::clean_cpuFeatures(); 395 396 __ bind(save_restore_except); 397 __ xorl(rsi, rsi); 398 VM_Version::set_cpuinfo_segv_addr(__ pc()); 399 // Generate SEGV 400 __ movl(rax, Address(rsi, 0)); 401 402 VM_Version::set_cpuinfo_cont_addr(__ pc()); 403 // Returns here after signal. Save xmm0 to check it later. 404 405 // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f 406 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset()))); 407 __ movl(rax, 0x10000); 408 __ andl(rax, Address(rsi, 4)); 409 __ cmpl(rax, 0x10000); 410 __ jccb(Assembler::notEqual, legacy_save_restore); 411 // check _cpuid_info.xem_xcr0_eax.bits.opmask 412 // check _cpuid_info.xem_xcr0_eax.bits.zmm512 413 // check _cpuid_info.xem_xcr0_eax.bits.zmm32 414 __ movl(rax, 0xE0); 415 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm 416 __ cmpl(rax, 0xE0); 417 __ jccb(Assembler::notEqual, legacy_save_restore); 418 419 // EVEX check: run in lowest evex mode 420 VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts 421 UseAVX = 3; 422 UseSSE = 2; 423 __ lea(rsi, Address(rbp, in_bytes(VM_Version::zmm_save_offset()))); 424 __ evmovdqul(Address(rsi, 0), xmm0, Assembler::AVX_512bit); 425 __ evmovdqul(Address(rsi, 64), xmm7, Assembler::AVX_512bit); 426#ifdef _LP64 427 __ evmovdqul(Address(rsi, 128), xmm8, Assembler::AVX_512bit); 428 __ evmovdqul(Address(rsi, 192), xmm31, Assembler::AVX_512bit); 429#endif 430 VM_Version::clean_cpuFeatures(); 431 UseAVX = saved_useavx; 432 UseSSE = saved_usesse; 433 __ jmp(wrapup); 434 435 __ bind(legacy_save_restore); 436 // AVX check 437 VM_Version::set_avx_cpuFeatures(); // Enable temporary to pass asserts 438 UseAVX = 1; 439 UseSSE = 2; 440 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ymm_save_offset()))); 441 __ vmovdqu(Address(rsi, 0), xmm0); 442 __ vmovdqu(Address(rsi, 32), xmm7); 443#ifdef _LP64 444 __ vmovdqu(Address(rsi, 64), xmm8); 445 __ vmovdqu(Address(rsi, 96), xmm15); 446#endif 447 VM_Version::clean_cpuFeatures(); 448 UseAVX = saved_useavx; 449 UseSSE = saved_usesse; 450 451 __ bind(wrapup); 452 __ popf(); 453 __ pop(rsi); 454 __ pop(rbx); 455 __ pop(rbp); 456 __ ret(0); 457 458# undef __ 459 460 return start; 461 }; 462}; 463 464void VM_Version::get_processor_features() { 465 466 _cpu = 4; // 486 by default 467 _model = 0; 468 _stepping = 0; 469 _features = 0; 470 _logical_processors_per_package = 1; 471 // i486 internal cache is both I&D and has a 16-byte line size 472 _L1_data_cache_line_size = 16; 473 474 // Get raw processor info 475 476 get_cpu_info_stub(&_cpuid_info); 477 478 assert_is_initialized(); 479 _cpu = extended_cpu_family(); 480 _model = extended_cpu_model(); 481 _stepping = cpu_stepping(); 482 483 if (cpu_family() > 4) { // it supports CPUID 484 _features = feature_flags(); 485 // Logical processors are only available on P4s and above, 486 // and only if hyperthreading is available. 487 _logical_processors_per_package = logical_processor_count(); 488 _L1_data_cache_line_size = L1_line_size(); 489 } 490 491 _supports_cx8 = supports_cmpxchg8(); 492 // xchg and xadd instructions 493 _supports_atomic_getset4 = true; 494 _supports_atomic_getadd4 = true; 495 LP64_ONLY(_supports_atomic_getset8 = true); 496 LP64_ONLY(_supports_atomic_getadd8 = true); 497 498#ifdef _LP64 499 // OS should support SSE for x64 and hardware should support at least SSE2. 500 if (!VM_Version::supports_sse2()) { 501 vm_exit_during_initialization("Unknown x64 processor: SSE2 not supported"); 502 } 503 // in 64 bit the use of SSE2 is the minimum 504 if (UseSSE < 2) UseSSE = 2; 505#endif 506 507#ifdef AMD64 508 // flush_icache_stub have to be generated first. 509 // That is why Icache line size is hard coded in ICache class, 510 // see icache_x86.hpp. It is also the reason why we can't use 511 // clflush instruction in 32-bit VM since it could be running 512 // on CPU which does not support it. 513 // 514 // The only thing we can do is to verify that flushed 515 // ICache::line_size has correct value. 516 guarantee(_cpuid_info.std_cpuid1_edx.bits.clflush != 0, "clflush is not supported"); 517 // clflush_size is size in quadwords (8 bytes). 518 guarantee(_cpuid_info.std_cpuid1_ebx.bits.clflush_size == 8, "such clflush size is not supported"); 519#endif 520 521 // If the OS doesn't support SSE, we can't use this feature even if the HW does 522 if (!os::supports_sse()) 523 _features &= ~(CPU_SSE|CPU_SSE2|CPU_SSE3|CPU_SSSE3|CPU_SSE4A|CPU_SSE4_1|CPU_SSE4_2); 524 525 if (UseSSE < 4) { 526 _features &= ~CPU_SSE4_1; 527 _features &= ~CPU_SSE4_2; 528 } 529 530 if (UseSSE < 3) { 531 _features &= ~CPU_SSE3; 532 _features &= ~CPU_SSSE3; 533 _features &= ~CPU_SSE4A; 534 } 535 536 if (UseSSE < 2) 537 _features &= ~CPU_SSE2; 538 539 if (UseSSE < 1) 540 _features &= ~CPU_SSE; 541 542 // first try initial setting and detect what we can support 543 if (UseAVX > 0) { 544 if (UseAVX > 2 && supports_evex()) { 545 UseAVX = 3; 546 } else if (UseAVX > 1 && supports_avx2()) { 547 UseAVX = 2; 548 } else if (UseAVX > 0 && supports_avx()) { 549 UseAVX = 1; 550 } else { 551 UseAVX = 0; 552 } 553 } else if (UseAVX < 0) { 554 UseAVX = 0; 555 } 556 557 if (UseAVX < 3) { 558 _features &= ~CPU_AVX512F; 559 _features &= ~CPU_AVX512DQ; 560 _features &= ~CPU_AVX512CD; 561 _features &= ~CPU_AVX512BW; 562 _features &= ~CPU_AVX512VL; 563 } 564 565 if (UseAVX < 2) 566 _features &= ~CPU_AVX2; 567 568 if (UseAVX < 1) 569 _features &= ~CPU_AVX; 570 571 if (!UseAES && !FLAG_IS_DEFAULT(UseAES)) 572 _features &= ~CPU_AES; 573 574 if (logical_processors_per_package() == 1) { 575 // HT processor could be installed on a system which doesn't support HT. 576 _features &= ~CPU_HT; 577 } 578 579 char buf[256]; 580 jio_snprintf(buf, sizeof(buf), "(%u cores per cpu, %u threads per core) family %d model %d stepping %d%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s%s", 581 cores_per_cpu(), threads_per_core(), 582 cpu_family(), _model, _stepping, 583 (supports_cmov() ? ", cmov" : ""), 584 (supports_cmpxchg8() ? ", cx8" : ""), 585 (supports_fxsr() ? ", fxsr" : ""), 586 (supports_mmx() ? ", mmx" : ""), 587 (supports_sse() ? ", sse" : ""), 588 (supports_sse2() ? ", sse2" : ""), 589 (supports_sse3() ? ", sse3" : ""), 590 (supports_ssse3()? ", ssse3": ""), 591 (supports_sse4_1() ? ", sse4.1" : ""), 592 (supports_sse4_2() ? ", sse4.2" : ""), 593 (supports_popcnt() ? ", popcnt" : ""), 594 (supports_avx() ? ", avx" : ""), 595 (supports_avx2() ? ", avx2" : ""), 596 (supports_aes() ? ", aes" : ""), 597 (supports_clmul() ? ", clmul" : ""), 598 (supports_erms() ? ", erms" : ""), 599 (supports_rtm() ? ", rtm" : ""), 600 (supports_mmx_ext() ? ", mmxext" : ""), 601 (supports_3dnow_prefetch() ? ", 3dnowpref" : ""), 602 (supports_lzcnt() ? ", lzcnt": ""), 603 (supports_sse4a() ? ", sse4a": ""), 604 (supports_ht() ? ", ht": ""), 605 (supports_tsc() ? ", tsc": ""), 606 (supports_tscinv_bit() ? ", tscinvbit": ""), 607 (supports_tscinv() ? ", tscinv": ""), 608 (supports_bmi1() ? ", bmi1" : ""), 609 (supports_bmi2() ? ", bmi2" : ""), 610 (supports_adx() ? ", adx" : ""), 611 (supports_evex() ? ", evex" : "")); 612 _features_string = os::strdup(buf); 613 614 // UseSSE is set to the smaller of what hardware supports and what 615 // the command line requires. I.e., you cannot set UseSSE to 2 on 616 // older Pentiums which do not support it. 617 if (UseSSE > 4) UseSSE=4; 618 if (UseSSE < 0) UseSSE=0; 619 if (!supports_sse4_1()) // Drop to 3 if no SSE4 support 620 UseSSE = MIN2((intx)3,UseSSE); 621 if (!supports_sse3()) // Drop to 2 if no SSE3 support 622 UseSSE = MIN2((intx)2,UseSSE); 623 if (!supports_sse2()) // Drop to 1 if no SSE2 support 624 UseSSE = MIN2((intx)1,UseSSE); 625 if (!supports_sse ()) // Drop to 0 if no SSE support 626 UseSSE = 0; 627 628 // Use AES instructions if available. 629 if (supports_aes()) { 630 if (FLAG_IS_DEFAULT(UseAES)) { 631 FLAG_SET_DEFAULT(UseAES, true); 632 } 633 if (!UseAES) { 634 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) { 635 warning("AES intrinsics require UseAES flag to be enabled. Intrinsics will be disabled."); 636 } 637 FLAG_SET_DEFAULT(UseAESIntrinsics, false); 638 } else { 639 if (UseSSE > 2) { 640 if (FLAG_IS_DEFAULT(UseAESIntrinsics)) { 641 FLAG_SET_DEFAULT(UseAESIntrinsics, true); 642 } 643 } else { 644 // The AES intrinsic stubs require AES instruction support (of course) 645 // but also require sse3 mode or higher for instructions it use. 646 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) { 647 warning("X86 AES intrinsics require SSE3 instructions or higher. Intrinsics will be disabled."); 648 } 649 FLAG_SET_DEFAULT(UseAESIntrinsics, false); 650 } 651 } 652 } else if (UseAES || UseAESIntrinsics) { 653 if (UseAES && !FLAG_IS_DEFAULT(UseAES)) { 654 warning("AES instructions are not available on this CPU"); 655 FLAG_SET_DEFAULT(UseAES, false); 656 } 657 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) { 658 warning("AES intrinsics are not available on this CPU"); 659 FLAG_SET_DEFAULT(UseAESIntrinsics, false); 660 } 661 } 662 663 // Use CLMUL instructions if available. 664 if (supports_clmul()) { 665 if (FLAG_IS_DEFAULT(UseCLMUL)) { 666 UseCLMUL = true; 667 } 668 } else if (UseCLMUL) { 669 if (!FLAG_IS_DEFAULT(UseCLMUL)) 670 warning("CLMUL instructions not available on this CPU (AVX may also be required)"); 671 FLAG_SET_DEFAULT(UseCLMUL, false); 672 } 673 674 if (UseCLMUL && (UseSSE > 2)) { 675 if (FLAG_IS_DEFAULT(UseCRC32Intrinsics)) { 676 UseCRC32Intrinsics = true; 677 } 678 } else if (UseCRC32Intrinsics) { 679 if (!FLAG_IS_DEFAULT(UseCRC32Intrinsics)) 680 warning("CRC32 Intrinsics requires CLMUL instructions (not available on this CPU)"); 681 FLAG_SET_DEFAULT(UseCRC32Intrinsics, false); 682 } 683 684 if (supports_sse4_2()) { 685 if (FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) { 686 UseCRC32CIntrinsics = true; 687 } 688 } 689 else if (UseCRC32CIntrinsics) { 690 if (!FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) { 691 warning("CRC32C intrinsics are not available on this CPU"); 692 } 693 FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false); 694 } 695 696 // GHASH/GCM intrinsics 697 if (UseCLMUL && (UseSSE > 2)) { 698 if (FLAG_IS_DEFAULT(UseGHASHIntrinsics)) { 699 UseGHASHIntrinsics = true; 700 } 701 } else if (UseGHASHIntrinsics) { 702 if (!FLAG_IS_DEFAULT(UseGHASHIntrinsics)) 703 warning("GHASH intrinsic requires CLMUL and SSE2 instructions on this CPU"); 704 FLAG_SET_DEFAULT(UseGHASHIntrinsics, false); 705 } 706 707 if (UseSHA) { 708 warning("SHA instructions are not available on this CPU"); 709 FLAG_SET_DEFAULT(UseSHA, false); 710 } 711 712 if (UseSHA1Intrinsics) { 713 warning("Intrinsics for SHA-1 crypto hash functions not available on this CPU."); 714 FLAG_SET_DEFAULT(UseSHA1Intrinsics, false); 715 } 716 717 if (UseSHA256Intrinsics) { 718 warning("Intrinsics for SHA-224 and SHA-256 crypto hash functions not available on this CPU."); 719 FLAG_SET_DEFAULT(UseSHA256Intrinsics, false); 720 } 721 722 if (UseSHA512Intrinsics) { 723 warning("Intrinsics for SHA-384 and SHA-512 crypto hash functions not available on this CPU."); 724 FLAG_SET_DEFAULT(UseSHA512Intrinsics, false); 725 } 726 727 if (UseAdler32Intrinsics) { 728 warning("Adler32Intrinsics not available on this CPU."); 729 FLAG_SET_DEFAULT(UseAdler32Intrinsics, false); 730 } 731 732 // Adjust RTM (Restricted Transactional Memory) flags 733 if (!supports_rtm() && UseRTMLocking) { 734 // Can't continue because UseRTMLocking affects UseBiasedLocking flag 735 // setting during arguments processing. See use_biased_locking(). 736 // VM_Version_init() is executed after UseBiasedLocking is used 737 // in Thread::allocate(). 738 vm_exit_during_initialization("RTM instructions are not available on this CPU"); 739 } 740 741#if INCLUDE_RTM_OPT 742 if (UseRTMLocking) { 743 if (is_intel_family_core()) { 744 if ((_model == CPU_MODEL_HASWELL_E3) || 745 (_model == CPU_MODEL_HASWELL_E7 && _stepping < 3) || 746 (_model == CPU_MODEL_BROADWELL && _stepping < 4)) { 747 // currently a collision between SKL and HSW_E3 748 if (!UnlockExperimentalVMOptions && UseAVX < 3) { 749 vm_exit_during_initialization("UseRTMLocking is only available as experimental option on this platform. It must be enabled via -XX:+UnlockExperimentalVMOptions flag."); 750 } else { 751 warning("UseRTMLocking is only available as experimental option on this platform."); 752 } 753 } 754 } 755 if (!FLAG_IS_CMDLINE(UseRTMLocking)) { 756 // RTM locking should be used only for applications with 757 // high lock contention. For now we do not use it by default. 758 vm_exit_during_initialization("UseRTMLocking flag should be only set on command line"); 759 } 760 if (!is_power_of_2(RTMTotalCountIncrRate)) { 761 warning("RTMTotalCountIncrRate must be a power of 2, resetting it to 64"); 762 FLAG_SET_DEFAULT(RTMTotalCountIncrRate, 64); 763 } 764 if (RTMAbortRatio < 0 || RTMAbortRatio > 100) { 765 warning("RTMAbortRatio must be in the range 0 to 100, resetting it to 50"); 766 FLAG_SET_DEFAULT(RTMAbortRatio, 50); 767 } 768 } else { // !UseRTMLocking 769 if (UseRTMForStackLocks) { 770 if (!FLAG_IS_DEFAULT(UseRTMForStackLocks)) { 771 warning("UseRTMForStackLocks flag should be off when UseRTMLocking flag is off"); 772 } 773 FLAG_SET_DEFAULT(UseRTMForStackLocks, false); 774 } 775 if (UseRTMDeopt) { 776 FLAG_SET_DEFAULT(UseRTMDeopt, false); 777 } 778 if (PrintPreciseRTMLockingStatistics) { 779 FLAG_SET_DEFAULT(PrintPreciseRTMLockingStatistics, false); 780 } 781 } 782#else 783 if (UseRTMLocking) { 784 // Only C2 does RTM locking optimization. 785 // Can't continue because UseRTMLocking affects UseBiasedLocking flag 786 // setting during arguments processing. See use_biased_locking(). 787 vm_exit_during_initialization("RTM locking optimization is not supported in this VM"); 788 } 789#endif 790 791#ifdef COMPILER2 792 if (UseFPUForSpilling) { 793 if (UseSSE < 2) { 794 // Only supported with SSE2+ 795 FLAG_SET_DEFAULT(UseFPUForSpilling, false); 796 } 797 } 798#endif 799#if defined(COMPILER2) || INCLUDE_JVMCI 800 if (MaxVectorSize > 0) { 801 if (!is_power_of_2(MaxVectorSize)) { 802 warning("MaxVectorSize must be a power of 2"); 803 FLAG_SET_DEFAULT(MaxVectorSize, 64); 804 } 805 if (MaxVectorSize > 64) { 806 FLAG_SET_DEFAULT(MaxVectorSize, 64); 807 } 808 if (MaxVectorSize > 16 && (UseAVX == 0 || !os_supports_avx_vectors())) { 809 // 32 bytes vectors (in YMM) are only supported with AVX+ 810 FLAG_SET_DEFAULT(MaxVectorSize, 16); 811 } 812 if (UseSSE < 2) { 813 // Vectors (in XMM) are only supported with SSE2+ 814 FLAG_SET_DEFAULT(MaxVectorSize, 0); 815 } 816#if defined(COMPILER2) && defined(ASSERT) 817 if (supports_avx() && PrintMiscellaneous && Verbose && TraceNewVectors) { 818 tty->print_cr("State of YMM registers after signal handle:"); 819 int nreg = 2 LP64_ONLY(+2); 820 const char* ymm_name[4] = {"0", "7", "8", "15"}; 821 for (int i = 0; i < nreg; i++) { 822 tty->print("YMM%s:", ymm_name[i]); 823 for (int j = 7; j >=0; j--) { 824 tty->print(" %x", _cpuid_info.ymm_save[i*8 + j]); 825 } 826 tty->cr(); 827 } 828 } 829#endif // COMPILER2 && ASSERT 830 } 831#endif // COMPILER2 || INCLUDE_JVMCI 832 833#ifdef COMPILER2 834#ifdef _LP64 835 if (FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) { 836 UseMultiplyToLenIntrinsic = true; 837 } 838 if (FLAG_IS_DEFAULT(UseSquareToLenIntrinsic)) { 839 UseSquareToLenIntrinsic = true; 840 } 841 if (FLAG_IS_DEFAULT(UseMulAddIntrinsic)) { 842 UseMulAddIntrinsic = true; 843 } 844 if (FLAG_IS_DEFAULT(UseMontgomeryMultiplyIntrinsic)) { 845 UseMontgomeryMultiplyIntrinsic = true; 846 } 847 if (FLAG_IS_DEFAULT(UseMontgomerySquareIntrinsic)) { 848 UseMontgomerySquareIntrinsic = true; 849 } 850#else 851 if (UseMultiplyToLenIntrinsic) { 852 if (!FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) { 853 warning("multiplyToLen intrinsic is not available in 32-bit VM"); 854 } 855 FLAG_SET_DEFAULT(UseMultiplyToLenIntrinsic, false); 856 } 857 if (UseMontgomeryMultiplyIntrinsic) { 858 if (!FLAG_IS_DEFAULT(UseMontgomeryMultiplyIntrinsic)) { 859 warning("montgomeryMultiply intrinsic is not available in 32-bit VM"); 860 } 861 FLAG_SET_DEFAULT(UseMontgomeryMultiplyIntrinsic, false); 862 } 863 if (UseMontgomerySquareIntrinsic) { 864 if (!FLAG_IS_DEFAULT(UseMontgomerySquareIntrinsic)) { 865 warning("montgomerySquare intrinsic is not available in 32-bit VM"); 866 } 867 FLAG_SET_DEFAULT(UseMontgomerySquareIntrinsic, false); 868 } 869 if (UseSquareToLenIntrinsic) { 870 if (!FLAG_IS_DEFAULT(UseSquareToLenIntrinsic)) { 871 warning("squareToLen intrinsic is not available in 32-bit VM"); 872 } 873 FLAG_SET_DEFAULT(UseSquareToLenIntrinsic, false); 874 } 875 if (UseMulAddIntrinsic) { 876 if (!FLAG_IS_DEFAULT(UseMulAddIntrinsic)) { 877 warning("mulAdd intrinsic is not available in 32-bit VM"); 878 } 879 FLAG_SET_DEFAULT(UseMulAddIntrinsic, false); 880 } 881#endif 882#endif // COMPILER2 883 884 // On new cpus instructions which update whole XMM register should be used 885 // to prevent partial register stall due to dependencies on high half. 886 // 887 // UseXmmLoadAndClearUpper == true --> movsd(xmm, mem) 888 // UseXmmLoadAndClearUpper == false --> movlpd(xmm, mem) 889 // UseXmmRegToRegMoveAll == true --> movaps(xmm, xmm), movapd(xmm, xmm). 890 // UseXmmRegToRegMoveAll == false --> movss(xmm, xmm), movsd(xmm, xmm). 891 892 if( is_amd() ) { // AMD cpus specific settings 893 if( supports_sse2() && FLAG_IS_DEFAULT(UseAddressNop) ) { 894 // Use it on new AMD cpus starting from Opteron. 895 UseAddressNop = true; 896 } 897 if( supports_sse2() && FLAG_IS_DEFAULT(UseNewLongLShift) ) { 898 // Use it on new AMD cpus starting from Opteron. 899 UseNewLongLShift = true; 900 } 901 if( FLAG_IS_DEFAULT(UseXmmLoadAndClearUpper) ) { 902 if (supports_sse4a()) { 903 UseXmmLoadAndClearUpper = true; // use movsd only on '10h' Opteron 904 } else { 905 UseXmmLoadAndClearUpper = false; 906 } 907 } 908 if( FLAG_IS_DEFAULT(UseXmmRegToRegMoveAll) ) { 909 if( supports_sse4a() ) { 910 UseXmmRegToRegMoveAll = true; // use movaps, movapd only on '10h' 911 } else { 912 UseXmmRegToRegMoveAll = false; 913 } 914 } 915 if( FLAG_IS_DEFAULT(UseXmmI2F) ) { 916 if( supports_sse4a() ) { 917 UseXmmI2F = true; 918 } else { 919 UseXmmI2F = false; 920 } 921 } 922 if( FLAG_IS_DEFAULT(UseXmmI2D) ) { 923 if( supports_sse4a() ) { 924 UseXmmI2D = true; 925 } else { 926 UseXmmI2D = false; 927 } 928 } 929 if (supports_sse4_2() && UseSSE >= 4) { 930 if (FLAG_IS_DEFAULT(UseSSE42Intrinsics)) { 931 FLAG_SET_DEFAULT(UseSSE42Intrinsics, true); 932 } 933 } else { 934 if (UseSSE42Intrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) { 935 warning("SSE4.2 intrinsics require SSE4.2 instructions or higher. Intrinsics will be disabled."); 936 } 937 FLAG_SET_DEFAULT(UseSSE42Intrinsics, false); 938 } 939 940 // some defaults for AMD family 15h 941 if ( cpu_family() == 0x15 ) { 942 // On family 15h processors default is no sw prefetch 943 if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) { 944 AllocatePrefetchStyle = 0; 945 } 946 // Also, if some other prefetch style is specified, default instruction type is PREFETCHW 947 if (FLAG_IS_DEFAULT(AllocatePrefetchInstr)) { 948 AllocatePrefetchInstr = 3; 949 } 950 // On family 15h processors use XMM and UnalignedLoadStores for Array Copy 951 if (supports_sse2() && FLAG_IS_DEFAULT(UseXMMForArrayCopy)) { 952 UseXMMForArrayCopy = true; 953 } 954 if (supports_sse2() && FLAG_IS_DEFAULT(UseUnalignedLoadStores)) { 955 UseUnalignedLoadStores = true; 956 } 957 } 958 959#ifdef COMPILER2 960 if (MaxVectorSize > 16) { 961 // Limit vectors size to 16 bytes on current AMD cpus. 962 FLAG_SET_DEFAULT(MaxVectorSize, 16); 963 } 964#endif // COMPILER2 965 } 966 967 if( is_intel() ) { // Intel cpus specific settings 968 if( FLAG_IS_DEFAULT(UseStoreImmI16) ) { 969 UseStoreImmI16 = false; // don't use it on Intel cpus 970 } 971 if( cpu_family() == 6 || cpu_family() == 15 ) { 972 if( FLAG_IS_DEFAULT(UseAddressNop) ) { 973 // Use it on all Intel cpus starting from PentiumPro 974 UseAddressNop = true; 975 } 976 } 977 if( FLAG_IS_DEFAULT(UseXmmLoadAndClearUpper) ) { 978 UseXmmLoadAndClearUpper = true; // use movsd on all Intel cpus 979 } 980 if( FLAG_IS_DEFAULT(UseXmmRegToRegMoveAll) ) { 981 if( supports_sse3() ) { 982 UseXmmRegToRegMoveAll = true; // use movaps, movapd on new Intel cpus 983 } else { 984 UseXmmRegToRegMoveAll = false; 985 } 986 } 987 if( cpu_family() == 6 && supports_sse3() ) { // New Intel cpus 988#ifdef COMPILER2 989 if( FLAG_IS_DEFAULT(MaxLoopPad) ) { 990 // For new Intel cpus do the next optimization: 991 // don't align the beginning of a loop if there are enough instructions 992 // left (NumberOfLoopInstrToAlign defined in c2_globals.hpp) 993 // in current fetch line (OptoLoopAlignment) or the padding 994 // is big (> MaxLoopPad). 995 // Set MaxLoopPad to 11 for new Intel cpus to reduce number of 996 // generated NOP instructions. 11 is the largest size of one 997 // address NOP instruction '0F 1F' (see Assembler::nop(i)). 998 MaxLoopPad = 11; 999 } 1000#endif // COMPILER2 1001 if (FLAG_IS_DEFAULT(UseXMMForArrayCopy)) { 1002 UseXMMForArrayCopy = true; // use SSE2 movq on new Intel cpus 1003 } 1004 if (supports_sse4_2() && supports_ht()) { // Newest Intel cpus 1005 if (FLAG_IS_DEFAULT(UseUnalignedLoadStores)) { 1006 UseUnalignedLoadStores = true; // use movdqu on newest Intel cpus 1007 } 1008 } 1009 if (supports_sse4_2() && UseSSE >= 4) { 1010 if (FLAG_IS_DEFAULT(UseSSE42Intrinsics)) { 1011 FLAG_SET_DEFAULT(UseSSE42Intrinsics, true); 1012 } 1013 } else { 1014 if (UseSSE42Intrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) { 1015 warning("SSE4.2 intrinsics require SSE4.2 instructions or higher. Intrinsics will be disabled."); 1016 } 1017 FLAG_SET_DEFAULT(UseSSE42Intrinsics, false); 1018 } 1019 } 1020 if ((cpu_family() == 0x06) && 1021 ((extended_cpu_model() == 0x36) || // Centerton 1022 (extended_cpu_model() == 0x37) || // Silvermont 1023 (extended_cpu_model() == 0x4D))) { 1024#ifdef COMPILER2 1025 if (FLAG_IS_DEFAULT(OptoScheduling)) { 1026 OptoScheduling = true; 1027 } 1028#endif 1029 if (supports_sse4_2()) { // Silvermont 1030 if (FLAG_IS_DEFAULT(UseUnalignedLoadStores)) { 1031 UseUnalignedLoadStores = true; // use movdqu on newest Intel cpus 1032 } 1033 } 1034 } 1035 if(FLAG_IS_DEFAULT(AllocatePrefetchInstr) && supports_3dnow_prefetch()) { 1036 AllocatePrefetchInstr = 3; 1037 } 1038 } 1039 1040#ifdef _LP64 1041 if (UseSSE42Intrinsics) { 1042 if (FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic)) { 1043 UseVectorizedMismatchIntrinsic = true; 1044 } 1045 } else if (UseVectorizedMismatchIntrinsic) { 1046 if (!FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic)) 1047 warning("vectorizedMismatch intrinsics are not available on this CPU"); 1048 FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false); 1049 } 1050#else 1051 if (UseVectorizedMismatchIntrinsic) { 1052 if (!FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic)) { 1053 warning("vectorizedMismatch intrinsic is not available in 32-bit VM"); 1054 } 1055 FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false); 1056 } 1057#endif // _LP64 1058 1059 // Use count leading zeros count instruction if available. 1060 if (supports_lzcnt()) { 1061 if (FLAG_IS_DEFAULT(UseCountLeadingZerosInstruction)) { 1062 UseCountLeadingZerosInstruction = true; 1063 } 1064 } else if (UseCountLeadingZerosInstruction) { 1065 warning("lzcnt instruction is not available on this CPU"); 1066 FLAG_SET_DEFAULT(UseCountLeadingZerosInstruction, false); 1067 } 1068 1069 // Use count trailing zeros instruction if available 1070 if (supports_bmi1()) { 1071 // tzcnt does not require VEX prefix 1072 if (FLAG_IS_DEFAULT(UseCountTrailingZerosInstruction)) { 1073 if (!UseBMI1Instructions && !FLAG_IS_DEFAULT(UseBMI1Instructions)) { 1074 // Don't use tzcnt if BMI1 is switched off on command line. 1075 UseCountTrailingZerosInstruction = false; 1076 } else { 1077 UseCountTrailingZerosInstruction = true; 1078 } 1079 } 1080 } else if (UseCountTrailingZerosInstruction) { 1081 warning("tzcnt instruction is not available on this CPU"); 1082 FLAG_SET_DEFAULT(UseCountTrailingZerosInstruction, false); 1083 } 1084 1085 // BMI instructions (except tzcnt) use an encoding with VEX prefix. 1086 // VEX prefix is generated only when AVX > 0. 1087 if (supports_bmi1() && supports_avx()) { 1088 if (FLAG_IS_DEFAULT(UseBMI1Instructions)) { 1089 UseBMI1Instructions = true; 1090 } 1091 } else if (UseBMI1Instructions) { 1092 warning("BMI1 instructions are not available on this CPU (AVX is also required)"); 1093 FLAG_SET_DEFAULT(UseBMI1Instructions, false); 1094 } 1095 1096 if (supports_bmi2() && supports_avx()) { 1097 if (FLAG_IS_DEFAULT(UseBMI2Instructions)) { 1098 UseBMI2Instructions = true; 1099 } 1100 } else if (UseBMI2Instructions) { 1101 warning("BMI2 instructions are not available on this CPU (AVX is also required)"); 1102 FLAG_SET_DEFAULT(UseBMI2Instructions, false); 1103 } 1104 1105 // Use population count instruction if available. 1106 if (supports_popcnt()) { 1107 if (FLAG_IS_DEFAULT(UsePopCountInstruction)) { 1108 UsePopCountInstruction = true; 1109 } 1110 } else if (UsePopCountInstruction) { 1111 warning("POPCNT instruction is not available on this CPU"); 1112 FLAG_SET_DEFAULT(UsePopCountInstruction, false); 1113 } 1114 1115 // Use fast-string operations if available. 1116 if (supports_erms()) { 1117 if (FLAG_IS_DEFAULT(UseFastStosb)) { 1118 UseFastStosb = true; 1119 } 1120 } else if (UseFastStosb) { 1121 warning("fast-string operations are not available on this CPU"); 1122 FLAG_SET_DEFAULT(UseFastStosb, false); 1123 } 1124 1125#ifdef COMPILER2 1126 if (FLAG_IS_DEFAULT(AlignVector)) { 1127 // Modern processors allow misaligned memory operations for vectors. 1128 AlignVector = !UseUnalignedLoadStores; 1129 } 1130#endif // COMPILER2 1131 1132 if( AllocatePrefetchInstr == 3 && !supports_3dnow_prefetch() ) AllocatePrefetchInstr=0; 1133 if( !supports_sse() && supports_3dnow_prefetch() ) AllocatePrefetchInstr = 3; 1134 1135 // Allocation prefetch settings 1136 intx cache_line_size = prefetch_data_size(); 1137 if( cache_line_size > AllocatePrefetchStepSize ) 1138 AllocatePrefetchStepSize = cache_line_size; 1139 1140 assert(AllocatePrefetchLines > 0, "invalid value"); 1141 if( AllocatePrefetchLines < 1 ) // set valid value in product VM 1142 AllocatePrefetchLines = 3; 1143 assert(AllocateInstancePrefetchLines > 0, "invalid value"); 1144 if( AllocateInstancePrefetchLines < 1 ) // set valid value in product VM 1145 AllocateInstancePrefetchLines = 1; 1146 1147 AllocatePrefetchDistance = allocate_prefetch_distance(); 1148 AllocatePrefetchStyle = allocate_prefetch_style(); 1149 1150 if (is_intel() && cpu_family() == 6 && supports_sse3()) { 1151 if (AllocatePrefetchStyle == 2) { // watermark prefetching on Core 1152#ifdef _LP64 1153 AllocatePrefetchDistance = 384; 1154#else 1155 AllocatePrefetchDistance = 320; 1156#endif 1157 } 1158 if (supports_sse4_2() && supports_ht()) { // Nehalem based cpus 1159 AllocatePrefetchDistance = 192; 1160 AllocatePrefetchLines = 4; 1161 } 1162#ifdef COMPILER2 1163 if (supports_sse4_2()) { 1164 if (FLAG_IS_DEFAULT(UseFPUForSpilling)) { 1165 FLAG_SET_DEFAULT(UseFPUForSpilling, true); 1166 } 1167 } 1168#endif 1169 } 1170 1171#ifdef _LP64 1172 // Prefetch settings 1173 PrefetchCopyIntervalInBytes = prefetch_copy_interval_in_bytes(); 1174 PrefetchScanIntervalInBytes = prefetch_scan_interval_in_bytes(); 1175 PrefetchFieldsAhead = prefetch_fields_ahead(); 1176#endif 1177 1178 if (FLAG_IS_DEFAULT(ContendedPaddingWidth) && 1179 (cache_line_size > ContendedPaddingWidth)) 1180 ContendedPaddingWidth = cache_line_size; 1181 1182 // This machine allows unaligned memory accesses 1183 if (FLAG_IS_DEFAULT(UseUnalignedAccesses)) { 1184 FLAG_SET_DEFAULT(UseUnalignedAccesses, true); 1185 } 1186 1187#ifndef PRODUCT 1188 if (PrintMiscellaneous && Verbose) { 1189 tty->print_cr("Logical CPUs per core: %u", 1190 logical_processors_per_package()); 1191 tty->print_cr("L1 data cache line size: %u", L1_data_cache_line_size()); 1192 tty->print("UseSSE=%d", (int) UseSSE); 1193 if (UseAVX > 0) { 1194 tty->print(" UseAVX=%d", (int) UseAVX); 1195 } 1196 if (UseAES) { 1197 tty->print(" UseAES=1"); 1198 } 1199#ifdef COMPILER2 1200 if (MaxVectorSize > 0) { 1201 tty->print(" MaxVectorSize=%d", (int) MaxVectorSize); 1202 } 1203#endif 1204 tty->cr(); 1205 tty->print("Allocation"); 1206 if (AllocatePrefetchStyle <= 0 || UseSSE == 0 && !supports_3dnow_prefetch()) { 1207 tty->print_cr(": no prefetching"); 1208 } else { 1209 tty->print(" prefetching: "); 1210 if (UseSSE == 0 && supports_3dnow_prefetch()) { 1211 tty->print("PREFETCHW"); 1212 } else if (UseSSE >= 1) { 1213 if (AllocatePrefetchInstr == 0) { 1214 tty->print("PREFETCHNTA"); 1215 } else if (AllocatePrefetchInstr == 1) { 1216 tty->print("PREFETCHT0"); 1217 } else if (AllocatePrefetchInstr == 2) { 1218 tty->print("PREFETCHT2"); 1219 } else if (AllocatePrefetchInstr == 3) { 1220 tty->print("PREFETCHW"); 1221 } 1222 } 1223 if (AllocatePrefetchLines > 1) { 1224 tty->print_cr(" at distance %d, %d lines of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchLines, (int) AllocatePrefetchStepSize); 1225 } else { 1226 tty->print_cr(" at distance %d, one line of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchStepSize); 1227 } 1228 } 1229 1230 if (PrefetchCopyIntervalInBytes > 0) { 1231 tty->print_cr("PrefetchCopyIntervalInBytes %d", (int) PrefetchCopyIntervalInBytes); 1232 } 1233 if (PrefetchScanIntervalInBytes > 0) { 1234 tty->print_cr("PrefetchScanIntervalInBytes %d", (int) PrefetchScanIntervalInBytes); 1235 } 1236 if (PrefetchFieldsAhead > 0) { 1237 tty->print_cr("PrefetchFieldsAhead %d", (int) PrefetchFieldsAhead); 1238 } 1239 if (ContendedPaddingWidth > 0) { 1240 tty->print_cr("ContendedPaddingWidth %d", (int) ContendedPaddingWidth); 1241 } 1242 } 1243#endif // !PRODUCT 1244} 1245 1246bool VM_Version::use_biased_locking() { 1247#if INCLUDE_RTM_OPT 1248 // RTM locking is most useful when there is high lock contention and 1249 // low data contention. With high lock contention the lock is usually 1250 // inflated and biased locking is not suitable for that case. 1251 // RTM locking code requires that biased locking is off. 1252 // Note: we can't switch off UseBiasedLocking in get_processor_features() 1253 // because it is used by Thread::allocate() which is called before 1254 // VM_Version::initialize(). 1255 if (UseRTMLocking && UseBiasedLocking) { 1256 if (FLAG_IS_DEFAULT(UseBiasedLocking)) { 1257 FLAG_SET_DEFAULT(UseBiasedLocking, false); 1258 } else { 1259 warning("Biased locking is not supported with RTM locking; ignoring UseBiasedLocking flag." ); 1260 UseBiasedLocking = false; 1261 } 1262 } 1263#endif 1264 return UseBiasedLocking; 1265} 1266 1267void VM_Version::initialize() { 1268 ResourceMark rm; 1269 // Making this stub must be FIRST use of assembler 1270 1271 stub_blob = BufferBlob::create("get_cpu_info_stub", stub_size); 1272 if (stub_blob == NULL) { 1273 vm_exit_during_initialization("Unable to allocate get_cpu_info_stub"); 1274 } 1275 CodeBuffer c(stub_blob); 1276 VM_Version_StubGenerator g(&c); 1277 get_cpu_info_stub = CAST_TO_FN_PTR(get_cpu_info_stub_t, 1278 g.generate_get_cpu_info()); 1279 1280 get_processor_features(); 1281} 1282