1 /*
2 * Copyright (c) 1997, 2017, 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 "logging/log.hpp"
29 #include "memory/resourceArea.hpp"
30 #include "prims/jvm.h"
31 #include "runtime/java.hpp"
32 #include "runtime/os.hpp"
33 #include "runtime/stubCodeGenerator.hpp"
34 #include "vm_version_x86.hpp"
35
36
37 int VM_Version::_cpu;
38 int VM_Version::_model;
39 int VM_Version::_stepping;
40 VM_Version::CpuidInfo VM_Version::_cpuid_info = { 0, };
41
42 // Address of instruction which causes SEGV
43 address VM_Version::_cpuinfo_segv_addr = 0;
44 // Address of instruction after the one which causes SEGV
45 address VM_Version::_cpuinfo_cont_addr = 0;
46
47 static BufferBlob* stub_blob;
48 static const int stub_size = 1000;
49
50 extern "C" {
51 typedef void (*get_cpu_info_stub_t)(void*);
52 }
53 static get_cpu_info_stub_t get_cpu_info_stub = NULL;
54
55
56 class VM_Version_StubGenerator: public StubCodeGenerator {
57 public:
58
59 VM_Version_StubGenerator(CodeBuffer *c) : StubCodeGenerator(c) {}
60
61 address generate_get_cpu_info() {
62 // Flags to test CPU type.
63 const uint32_t HS_EFL_AC = 0x40000;
64 const uint32_t HS_EFL_ID = 0x200000;
65 // Values for when we don't have a CPUID instruction.
66 const int CPU_FAMILY_SHIFT = 8;
67 const uint32_t CPU_FAMILY_386 = (3 << CPU_FAMILY_SHIFT);
68 const uint32_t CPU_FAMILY_486 = (4 << CPU_FAMILY_SHIFT);
69 bool use_evex = FLAG_IS_DEFAULT(UseAVX) || (UseAVX > 2);
70
71 Label detect_486, cpu486, detect_586, std_cpuid1, std_cpuid4;
72 Label sef_cpuid, ext_cpuid, ext_cpuid1, ext_cpuid5, ext_cpuid7, done, wrapup;
73 Label legacy_setup, save_restore_except, legacy_save_restore, start_simd_check;
74
75 StubCodeMark mark(this, "VM_Version", "get_cpu_info_stub");
76 # define __ _masm->
77
78 address start = __ pc();
79
80 //
81 // void get_cpu_info(VM_Version::CpuidInfo* cpuid_info);
82 //
83 // LP64: rcx and rdx are first and second argument registers on windows
84
85 __ push(rbp);
86 #ifdef _LP64
87 __ mov(rbp, c_rarg0); // cpuid_info address
88 #else
89 __ movptr(rbp, Address(rsp, 8)); // cpuid_info address
90 #endif
91 __ push(rbx);
92 __ push(rsi);
93 __ pushf(); // preserve rbx, and flags
94 __ pop(rax);
95 __ push(rax);
96 __ mov(rcx, rax);
97 //
98 // if we are unable to change the AC flag, we have a 386
99 //
100 __ xorl(rax, HS_EFL_AC);
101 __ push(rax);
102 __ popf();
103 __ pushf();
104 __ pop(rax);
105 __ cmpptr(rax, rcx);
106 __ jccb(Assembler::notEqual, detect_486);
107
108 __ movl(rax, CPU_FAMILY_386);
109 __ movl(Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())), rax);
110 __ jmp(done);
111
112 //
113 // If we are unable to change the ID flag, we have a 486 which does
114 // not support the "cpuid" instruction.
115 //
116 __ bind(detect_486);
117 __ mov(rax, rcx);
118 __ xorl(rax, HS_EFL_ID);
119 __ push(rax);
120 __ popf();
121 __ pushf();
122 __ pop(rax);
123 __ cmpptr(rcx, rax);
124 __ jccb(Assembler::notEqual, detect_586);
125
126 __ bind(cpu486);
127 __ movl(rax, CPU_FAMILY_486);
128 __ movl(Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())), rax);
129 __ jmp(done);
130
131 //
132 // At this point, we have a chip which supports the "cpuid" instruction
133 //
134 __ bind(detect_586);
135 __ xorl(rax, rax);
136 __ cpuid();
137 __ orl(rax, rax);
138 __ jcc(Assembler::equal, cpu486); // if cpuid doesn't support an input
139 // value of at least 1, we give up and
140 // assume a 486
141 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset())));
142 __ movl(Address(rsi, 0), rax);
143 __ movl(Address(rsi, 4), rbx);
144 __ movl(Address(rsi, 8), rcx);
145 __ movl(Address(rsi,12), rdx);
146
147 __ cmpl(rax, 0xa); // Is cpuid(0xB) supported?
148 __ jccb(Assembler::belowEqual, std_cpuid4);
149
150 //
151 // cpuid(0xB) Processor Topology
152 //
153 __ movl(rax, 0xb);
154 __ xorl(rcx, rcx); // Threads level
155 __ cpuid();
156
157 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB0_offset())));
158 __ movl(Address(rsi, 0), rax);
159 __ movl(Address(rsi, 4), rbx);
160 __ movl(Address(rsi, 8), rcx);
161 __ movl(Address(rsi,12), rdx);
162
163 __ movl(rax, 0xb);
164 __ movl(rcx, 1); // Cores level
165 __ cpuid();
166 __ push(rax);
167 __ andl(rax, 0x1f); // Determine if valid topology level
168 __ orl(rax, rbx); // eax[4:0] | ebx[0:15] == 0 indicates invalid level
169 __ andl(rax, 0xffff);
170 __ pop(rax);
171 __ jccb(Assembler::equal, std_cpuid4);
172
173 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB1_offset())));
174 __ movl(Address(rsi, 0), rax);
175 __ movl(Address(rsi, 4), rbx);
176 __ movl(Address(rsi, 8), rcx);
177 __ movl(Address(rsi,12), rdx);
178
179 __ movl(rax, 0xb);
180 __ movl(rcx, 2); // Packages level
181 __ cpuid();
182 __ push(rax);
183 __ andl(rax, 0x1f); // Determine if valid topology level
184 __ orl(rax, rbx); // eax[4:0] | ebx[0:15] == 0 indicates invalid level
185 __ andl(rax, 0xffff);
186 __ pop(rax);
187 __ jccb(Assembler::equal, std_cpuid4);
188
189 __ lea(rsi, Address(rbp, in_bytes(VM_Version::tpl_cpuidB2_offset())));
190 __ movl(Address(rsi, 0), rax);
191 __ movl(Address(rsi, 4), rbx);
192 __ movl(Address(rsi, 8), rcx);
193 __ movl(Address(rsi,12), rdx);
194
195 //
196 // cpuid(0x4) Deterministic cache params
197 //
198 __ bind(std_cpuid4);
199 __ movl(rax, 4);
200 __ cmpl(rax, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset()))); // Is cpuid(0x4) supported?
201 __ jccb(Assembler::greater, std_cpuid1);
202
203 __ xorl(rcx, rcx); // L1 cache
204 __ cpuid();
205 __ push(rax);
206 __ andl(rax, 0x1f); // Determine if valid cache parameters used
207 __ orl(rax, rax); // eax[4:0] == 0 indicates invalid cache
208 __ pop(rax);
209 __ jccb(Assembler::equal, std_cpuid1);
210
211 __ lea(rsi, Address(rbp, in_bytes(VM_Version::dcp_cpuid4_offset())));
212 __ movl(Address(rsi, 0), rax);
213 __ movl(Address(rsi, 4), rbx);
214 __ movl(Address(rsi, 8), rcx);
215 __ movl(Address(rsi,12), rdx);
216
217 //
218 // Standard cpuid(0x1)
219 //
220 __ bind(std_cpuid1);
221 __ movl(rax, 1);
222 __ cpuid();
223 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
224 __ movl(Address(rsi, 0), rax);
225 __ movl(Address(rsi, 4), rbx);
226 __ movl(Address(rsi, 8), rcx);
227 __ movl(Address(rsi,12), rdx);
228
229 //
230 // Check if OS has enabled XGETBV instruction to access XCR0
231 // (OSXSAVE feature flag) and CPU supports AVX
232 //
233 __ andl(rcx, 0x18000000); // cpuid1 bits osxsave | avx
234 __ cmpl(rcx, 0x18000000);
235 __ jccb(Assembler::notEqual, sef_cpuid); // jump if AVX is not supported
236
237 //
238 // XCR0, XFEATURE_ENABLED_MASK register
239 //
240 __ xorl(rcx, rcx); // zero for XCR0 register
241 __ xgetbv();
242 __ lea(rsi, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset())));
243 __ movl(Address(rsi, 0), rax);
244 __ movl(Address(rsi, 4), rdx);
245
246 //
247 // cpuid(0x7) Structured Extended Features
248 //
249 __ bind(sef_cpuid);
250 __ movl(rax, 7);
251 __ cmpl(rax, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset()))); // Is cpuid(0x7) supported?
252 __ jccb(Assembler::greater, ext_cpuid);
253
254 __ xorl(rcx, rcx);
255 __ cpuid();
256 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
257 __ movl(Address(rsi, 0), rax);
258 __ movl(Address(rsi, 4), rbx);
259
260 //
261 // Extended cpuid(0x80000000)
262 //
263 __ bind(ext_cpuid);
264 __ movl(rax, 0x80000000);
265 __ cpuid();
266 __ cmpl(rax, 0x80000000); // Is cpuid(0x80000001) supported?
267 __ jcc(Assembler::belowEqual, done);
268 __ cmpl(rax, 0x80000004); // Is cpuid(0x80000005) supported?
269 __ jccb(Assembler::belowEqual, ext_cpuid1);
270 __ cmpl(rax, 0x80000006); // Is cpuid(0x80000007) supported?
271 __ jccb(Assembler::belowEqual, ext_cpuid5);
272 __ cmpl(rax, 0x80000007); // Is cpuid(0x80000008) supported?
273 __ jccb(Assembler::belowEqual, ext_cpuid7);
274 //
275 // Extended cpuid(0x80000008)
276 //
277 __ movl(rax, 0x80000008);
278 __ cpuid();
279 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid8_offset())));
280 __ movl(Address(rsi, 0), rax);
281 __ movl(Address(rsi, 4), rbx);
282 __ movl(Address(rsi, 8), rcx);
283 __ movl(Address(rsi,12), rdx);
284
285 //
286 // Extended cpuid(0x80000007)
287 //
288 __ bind(ext_cpuid7);
289 __ movl(rax, 0x80000007);
290 __ cpuid();
291 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid7_offset())));
292 __ movl(Address(rsi, 0), rax);
293 __ movl(Address(rsi, 4), rbx);
294 __ movl(Address(rsi, 8), rcx);
295 __ movl(Address(rsi,12), rdx);
296
297 //
298 // Extended cpuid(0x80000005)
299 //
300 __ bind(ext_cpuid5);
301 __ movl(rax, 0x80000005);
302 __ cpuid();
303 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid5_offset())));
304 __ movl(Address(rsi, 0), rax);
305 __ movl(Address(rsi, 4), rbx);
306 __ movl(Address(rsi, 8), rcx);
307 __ movl(Address(rsi,12), rdx);
308
309 //
310 // Extended cpuid(0x80000001)
311 //
312 __ bind(ext_cpuid1);
313 __ movl(rax, 0x80000001);
314 __ cpuid();
315 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ext_cpuid1_offset())));
316 __ movl(Address(rsi, 0), rax);
317 __ movl(Address(rsi, 4), rbx);
318 __ movl(Address(rsi, 8), rcx);
319 __ movl(Address(rsi,12), rdx);
320
321 //
322 // Check if OS has enabled XGETBV instruction to access XCR0
323 // (OSXSAVE feature flag) and CPU supports AVX
324 //
325 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
326 __ movl(rcx, 0x18000000); // cpuid1 bits osxsave | avx
327 __ andl(rcx, Address(rsi, 8)); // cpuid1 bits osxsave | avx
328 __ cmpl(rcx, 0x18000000);
329 __ jccb(Assembler::notEqual, done); // jump if AVX is not supported
330
331 __ movl(rax, 0x6);
332 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
333 __ cmpl(rax, 0x6);
334 __ jccb(Assembler::equal, start_simd_check); // return if AVX is not supported
335
336 // we need to bridge farther than imm8, so we use this island as a thunk
337 __ bind(done);
338 __ jmp(wrapup);
339
340 __ bind(start_simd_check);
341 //
342 // Some OSs have a bug when upper 128/256bits of YMM/ZMM
343 // registers are not restored after a signal processing.
344 // Generate SEGV here (reference through NULL)
345 // and check upper YMM/ZMM bits after it.
346 //
347 intx saved_useavx = UseAVX;
348 intx saved_usesse = UseSSE;
349 // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
350 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
351 __ movl(rax, 0x10000);
352 __ andl(rax, Address(rsi, 4)); // xcr0 bits sse | ymm
353 __ cmpl(rax, 0x10000);
354 __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
355 // check _cpuid_info.xem_xcr0_eax.bits.opmask
356 // check _cpuid_info.xem_xcr0_eax.bits.zmm512
357 // check _cpuid_info.xem_xcr0_eax.bits.zmm32
358 __ movl(rax, 0xE0);
359 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
360 __ cmpl(rax, 0xE0);
361 __ jccb(Assembler::notEqual, legacy_setup); // jump if EVEX is not supported
362
363 // If UseAVX is unitialized or is set by the user to include EVEX
364 if (use_evex) {
365 // EVEX setup: run in lowest evex mode
366 VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts
367 UseAVX = 3;
368 UseSSE = 2;
369 #ifdef _WINDOWS
370 // xmm5-xmm15 are not preserved by caller on windows
371 // https://msdn.microsoft.com/en-us/library/9z1stfyw.aspx
372 __ subptr(rsp, 64);
373 __ evmovdqul(Address(rsp, 0), xmm7, Assembler::AVX_512bit);
374 #ifdef _LP64
375 __ subptr(rsp, 64);
376 __ evmovdqul(Address(rsp, 0), xmm8, Assembler::AVX_512bit);
377 __ subptr(rsp, 64);
378 __ evmovdqul(Address(rsp, 0), xmm31, Assembler::AVX_512bit);
379 #endif // _LP64
380 #endif // _WINDOWS
381
382 // load value into all 64 bytes of zmm7 register
383 __ movl(rcx, VM_Version::ymm_test_value());
384 __ movdl(xmm0, rcx);
385 __ movl(rcx, 0xffff);
386 __ kmovwl(k1, rcx);
387 __ evpbroadcastd(xmm0, xmm0, Assembler::AVX_512bit);
388 __ evmovdqul(xmm7, xmm0, Assembler::AVX_512bit);
389 #ifdef _LP64
390 __ evmovdqul(xmm8, xmm0, Assembler::AVX_512bit);
391 __ evmovdqul(xmm31, xmm0, Assembler::AVX_512bit);
392 #endif
393 VM_Version::clean_cpuFeatures();
394 __ jmp(save_restore_except);
395 }
396
397 __ bind(legacy_setup);
398 // AVX setup
399 VM_Version::set_avx_cpuFeatures(); // Enable temporary to pass asserts
400 UseAVX = 1;
401 UseSSE = 2;
402 #ifdef _WINDOWS
403 __ subptr(rsp, 32);
404 __ vmovdqu(Address(rsp, 0), xmm7);
405 #ifdef _LP64
406 __ subptr(rsp, 32);
407 __ vmovdqu(Address(rsp, 0), xmm8);
408 __ subptr(rsp, 32);
409 __ vmovdqu(Address(rsp, 0), xmm15);
410 #endif // _LP64
411 #endif // _WINDOWS
412
413 // load value into all 32 bytes of ymm7 register
414 __ movl(rcx, VM_Version::ymm_test_value());
415
416 __ movdl(xmm0, rcx);
417 __ pshufd(xmm0, xmm0, 0x00);
418 __ vinsertf128_high(xmm0, xmm0);
419 __ vmovdqu(xmm7, xmm0);
420 #ifdef _LP64
421 __ vmovdqu(xmm8, xmm0);
422 __ vmovdqu(xmm15, xmm0);
423 #endif
424 VM_Version::clean_cpuFeatures();
425
426 __ bind(save_restore_except);
427 __ xorl(rsi, rsi);
428 VM_Version::set_cpuinfo_segv_addr(__ pc());
429 // Generate SEGV
430 __ movl(rax, Address(rsi, 0));
431
432 VM_Version::set_cpuinfo_cont_addr(__ pc());
433 // Returns here after signal. Save xmm0 to check it later.
434
435 // check _cpuid_info.sef_cpuid7_ebx.bits.avx512f
436 __ lea(rsi, Address(rbp, in_bytes(VM_Version::sef_cpuid7_offset())));
437 __ movl(rax, 0x10000);
438 __ andl(rax, Address(rsi, 4));
439 __ cmpl(rax, 0x10000);
440 __ jcc(Assembler::notEqual, legacy_save_restore);
441 // check _cpuid_info.xem_xcr0_eax.bits.opmask
442 // check _cpuid_info.xem_xcr0_eax.bits.zmm512
443 // check _cpuid_info.xem_xcr0_eax.bits.zmm32
444 __ movl(rax, 0xE0);
445 __ andl(rax, Address(rbp, in_bytes(VM_Version::xem_xcr0_offset()))); // xcr0 bits sse | ymm
446 __ cmpl(rax, 0xE0);
447 __ jcc(Assembler::notEqual, legacy_save_restore);
448
449 // If UseAVX is unitialized or is set by the user to include EVEX
450 if (use_evex) {
451 // EVEX check: run in lowest evex mode
452 VM_Version::set_evex_cpuFeatures(); // Enable temporary to pass asserts
453 UseAVX = 3;
454 UseSSE = 2;
455 __ lea(rsi, Address(rbp, in_bytes(VM_Version::zmm_save_offset())));
456 __ evmovdqul(Address(rsi, 0), xmm0, Assembler::AVX_512bit);
457 __ evmovdqul(Address(rsi, 64), xmm7, Assembler::AVX_512bit);
458 #ifdef _LP64
459 __ evmovdqul(Address(rsi, 128), xmm8, Assembler::AVX_512bit);
460 __ evmovdqul(Address(rsi, 192), xmm31, Assembler::AVX_512bit);
461 #endif
462
463 #ifdef _WINDOWS
464 #ifdef _LP64
465 __ evmovdqul(xmm31, Address(rsp, 0), Assembler::AVX_512bit);
466 __ addptr(rsp, 64);
467 __ evmovdqul(xmm8, Address(rsp, 0), Assembler::AVX_512bit);
468 __ addptr(rsp, 64);
469 #endif // _LP64
470 __ evmovdqul(xmm7, Address(rsp, 0), Assembler::AVX_512bit);
471 __ addptr(rsp, 64);
472 #endif // _WINDOWS
473 generate_vzeroupper(wrapup);
474 VM_Version::clean_cpuFeatures();
475 UseAVX = saved_useavx;
476 UseSSE = saved_usesse;
477 __ jmp(wrapup);
478 }
479
480 __ bind(legacy_save_restore);
481 // AVX check
482 VM_Version::set_avx_cpuFeatures(); // Enable temporary to pass asserts
483 UseAVX = 1;
484 UseSSE = 2;
485 __ lea(rsi, Address(rbp, in_bytes(VM_Version::ymm_save_offset())));
486 __ vmovdqu(Address(rsi, 0), xmm0);
487 __ vmovdqu(Address(rsi, 32), xmm7);
488 #ifdef _LP64
489 __ vmovdqu(Address(rsi, 64), xmm8);
490 __ vmovdqu(Address(rsi, 96), xmm15);
491 #endif
492
493 #ifdef _WINDOWS
494 #ifdef _LP64
495 __ vmovdqu(xmm15, Address(rsp, 0));
496 __ addptr(rsp, 32);
497 __ vmovdqu(xmm8, Address(rsp, 0));
498 __ addptr(rsp, 32);
499 #endif // _LP64
500 __ vmovdqu(xmm7, Address(rsp, 0));
501 __ addptr(rsp, 32);
502 #endif // _WINDOWS
503 generate_vzeroupper(wrapup);
504 VM_Version::clean_cpuFeatures();
505 UseAVX = saved_useavx;
506 UseSSE = saved_usesse;
507
508 __ bind(wrapup);
509 __ popf();
510 __ pop(rsi);
511 __ pop(rbx);
512 __ pop(rbp);
513 __ ret(0);
514
515 # undef __
516
517 return start;
518 };
519 void generate_vzeroupper(Label& L_wrapup) {
520 # define __ _masm->
521 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid0_offset())));
522 __ cmpl(Address(rsi, 4), 0x756e6547); // 'uneG'
523 __ jcc(Assembler::notEqual, L_wrapup);
524 __ movl(rcx, 0x0FFF0FF0);
525 __ lea(rsi, Address(rbp, in_bytes(VM_Version::std_cpuid1_offset())));
526 __ andl(rcx, Address(rsi, 0));
527 __ cmpl(rcx, 0x00050670); // If it is Xeon Phi 3200/5200/7200
528 __ jcc(Assembler::equal, L_wrapup);
529 __ cmpl(rcx, 0x00080650); // If it is Future Xeon Phi
530 __ jcc(Assembler::equal, L_wrapup);
531 __ vzeroupper();
532 # undef __
533 }
534 };
535
536 void VM_Version::get_processor_features() {
537
538 _cpu = 4; // 486 by default
539 _model = 0;
540 _stepping = 0;
541 _features = 0;
542 _logical_processors_per_package = 1;
543 // i486 internal cache is both I&D and has a 16-byte line size
544 _L1_data_cache_line_size = 16;
545
546 // Get raw processor info
547
548 get_cpu_info_stub(&_cpuid_info);
549
550 assert_is_initialized();
551 _cpu = extended_cpu_family();
552 _model = extended_cpu_model();
553 _stepping = cpu_stepping();
554
555 if (cpu_family() > 4) { // it supports CPUID
556 _features = feature_flags();
557 // Logical processors are only available on P4s and above,
558 // and only if hyperthreading is available.
559 _logical_processors_per_package = logical_processor_count();
560 _L1_data_cache_line_size = L1_line_size();
561 }
562
563 _supports_cx8 = supports_cmpxchg8();
564 // xchg and xadd instructions
565 _supports_atomic_getset4 = true;
566 _supports_atomic_getadd4 = true;
567 LP64_ONLY(_supports_atomic_getset8 = true);
568 LP64_ONLY(_supports_atomic_getadd8 = true);
569
570 #ifdef _LP64
571 // OS should support SSE for x64 and hardware should support at least SSE2.
572 if (!VM_Version::supports_sse2()) {
573 vm_exit_during_initialization("Unknown x64 processor: SSE2 not supported");
574 }
575 // in 64 bit the use of SSE2 is the minimum
576 if (UseSSE < 2) UseSSE = 2;
577 #endif
578
579 #ifdef AMD64
580 // flush_icache_stub have to be generated first.
581 // That is why Icache line size is hard coded in ICache class,
582 // see icache_x86.hpp. It is also the reason why we can't use
583 // clflush instruction in 32-bit VM since it could be running
584 // on CPU which does not support it.
585 //
586 // The only thing we can do is to verify that flushed
587 // ICache::line_size has correct value.
588 guarantee(_cpuid_info.std_cpuid1_edx.bits.clflush != 0, "clflush is not supported");
589 // clflush_size is size in quadwords (8 bytes).
590 guarantee(_cpuid_info.std_cpuid1_ebx.bits.clflush_size == 8, "such clflush size is not supported");
591 #endif
592
593 // If the OS doesn't support SSE, we can't use this feature even if the HW does
594 if (!os::supports_sse())
595 _features &= ~(CPU_SSE|CPU_SSE2|CPU_SSE3|CPU_SSSE3|CPU_SSE4A|CPU_SSE4_1|CPU_SSE4_2);
596
597 if (UseSSE < 4) {
598 _features &= ~CPU_SSE4_1;
599 _features &= ~CPU_SSE4_2;
600 }
601
602 if (UseSSE < 3) {
603 _features &= ~CPU_SSE3;
604 _features &= ~CPU_SSSE3;
605 _features &= ~CPU_SSE4A;
606 }
607
608 if (UseSSE < 2)
609 _features &= ~CPU_SSE2;
610
611 if (UseSSE < 1)
612 _features &= ~CPU_SSE;
613
614 // first try initial setting and detect what we can support
615 if (UseAVX > 0) {
616 if (UseAVX > 2 && supports_evex()) {
617 UseAVX = 3;
618 } else if (UseAVX > 1 && supports_avx2()) {
619 UseAVX = 2;
620 } else if (UseAVX > 0 && supports_avx()) {
621 UseAVX = 1;
622 } else {
623 UseAVX = 0;
624 }
625 } else if (UseAVX < 0) {
626 UseAVX = 0;
627 }
628
629 if (UseAVX < 3) {
630 _features &= ~CPU_AVX512F;
631 _features &= ~CPU_AVX512DQ;
632 _features &= ~CPU_AVX512CD;
633 _features &= ~CPU_AVX512BW;
634 _features &= ~CPU_AVX512VL;
635 }
636
637 if (UseAVX < 2)
638 _features &= ~CPU_AVX2;
639
640 if (UseAVX < 1) {
641 _features &= ~CPU_AVX;
642 _features &= ~CPU_VZEROUPPER;
643 }
644
645 if (logical_processors_per_package() == 1) {
646 // HT processor could be installed on a system which doesn't support HT.
647 _features &= ~CPU_HT;
648 }
649
650 if( is_intel() ) { // Intel cpus specific settings
651 if (is_knights_family()) {
652 _features &= ~CPU_VZEROUPPER;
653 }
654 }
655
656 char buf[256];
657 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%s%s",
658 cores_per_cpu(), threads_per_core(),
659 cpu_family(), _model, _stepping,
660 (supports_cmov() ? ", cmov" : ""),
661 (supports_cmpxchg8() ? ", cx8" : ""),
662 (supports_fxsr() ? ", fxsr" : ""),
663 (supports_mmx() ? ", mmx" : ""),
664 (supports_sse() ? ", sse" : ""),
665 (supports_sse2() ? ", sse2" : ""),
666 (supports_sse3() ? ", sse3" : ""),
667 (supports_ssse3()? ", ssse3": ""),
668 (supports_sse4_1() ? ", sse4.1" : ""),
669 (supports_sse4_2() ? ", sse4.2" : ""),
670 (supports_popcnt() ? ", popcnt" : ""),
671 (supports_avx() ? ", avx" : ""),
672 (supports_avx2() ? ", avx2" : ""),
673 (supports_aes() ? ", aes" : ""),
674 (supports_clmul() ? ", clmul" : ""),
675 (supports_erms() ? ", erms" : ""),
676 (supports_rtm() ? ", rtm" : ""),
677 (supports_mmx_ext() ? ", mmxext" : ""),
678 (supports_3dnow_prefetch() ? ", 3dnowpref" : ""),
679 (supports_lzcnt() ? ", lzcnt": ""),
680 (supports_sse4a() ? ", sse4a": ""),
681 (supports_ht() ? ", ht": ""),
682 (supports_tsc() ? ", tsc": ""),
683 (supports_tscinv_bit() ? ", tscinvbit": ""),
684 (supports_tscinv() ? ", tscinv": ""),
685 (supports_bmi1() ? ", bmi1" : ""),
686 (supports_bmi2() ? ", bmi2" : ""),
687 (supports_adx() ? ", adx" : ""),
688 (supports_evex() ? ", evex" : ""),
689 (supports_sha() ? ", sha" : ""),
690 (supports_fma() ? ", fma" : ""));
691 _features_string = os::strdup(buf);
692
693 // UseSSE is set to the smaller of what hardware supports and what
694 // the command line requires. I.e., you cannot set UseSSE to 2 on
695 // older Pentiums which do not support it.
696 if (UseSSE > 4) UseSSE=4;
697 if (UseSSE < 0) UseSSE=0;
698 if (!supports_sse4_1()) // Drop to 3 if no SSE4 support
699 UseSSE = MIN2((intx)3,UseSSE);
700 if (!supports_sse3()) // Drop to 2 if no SSE3 support
701 UseSSE = MIN2((intx)2,UseSSE);
702 if (!supports_sse2()) // Drop to 1 if no SSE2 support
703 UseSSE = MIN2((intx)1,UseSSE);
704 if (!supports_sse ()) // Drop to 0 if no SSE support
705 UseSSE = 0;
706
707 // Use AES instructions if available.
708 if (supports_aes()) {
709 if (FLAG_IS_DEFAULT(UseAES)) {
710 FLAG_SET_DEFAULT(UseAES, true);
711 }
712 if (!UseAES) {
713 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
714 warning("AES intrinsics require UseAES flag to be enabled. Intrinsics will be disabled.");
715 }
716 FLAG_SET_DEFAULT(UseAESIntrinsics, false);
717 } else {
718 if (UseSSE > 2) {
719 if (FLAG_IS_DEFAULT(UseAESIntrinsics)) {
720 FLAG_SET_DEFAULT(UseAESIntrinsics, true);
721 }
722 } else {
723 // The AES intrinsic stubs require AES instruction support (of course)
724 // but also require sse3 mode or higher for instructions it use.
725 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
726 warning("X86 AES intrinsics require SSE3 instructions or higher. Intrinsics will be disabled.");
727 }
728 FLAG_SET_DEFAULT(UseAESIntrinsics, false);
729 }
730
731 // --AES-CTR begins--
732 if (!UseAESIntrinsics) {
733 if (UseAESCTRIntrinsics && !FLAG_IS_DEFAULT(UseAESCTRIntrinsics)) {
734 warning("AES-CTR intrinsics require UseAESIntrinsics flag to be enabled. Intrinsics will be disabled.");
735 FLAG_SET_DEFAULT(UseAESCTRIntrinsics, false);
736 }
737 } else {
738 if(supports_sse4_1()) {
739 if (FLAG_IS_DEFAULT(UseAESCTRIntrinsics)) {
740 FLAG_SET_DEFAULT(UseAESCTRIntrinsics, true);
741 }
742 } else {
743 // The AES-CTR intrinsic stubs require AES instruction support (of course)
744 // but also require sse4.1 mode or higher for instructions it use.
745 if (UseAESCTRIntrinsics && !FLAG_IS_DEFAULT(UseAESCTRIntrinsics)) {
746 warning("X86 AES-CTR intrinsics require SSE4.1 instructions or higher. Intrinsics will be disabled.");
747 }
748 FLAG_SET_DEFAULT(UseAESCTRIntrinsics, false);
749 }
750 }
751 // --AES-CTR ends--
752 }
753 } else if (UseAES || UseAESIntrinsics || UseAESCTRIntrinsics) {
754 if (UseAES && !FLAG_IS_DEFAULT(UseAES)) {
755 warning("AES instructions are not available on this CPU");
756 FLAG_SET_DEFAULT(UseAES, false);
757 }
758 if (UseAESIntrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
759 warning("AES intrinsics are not available on this CPU");
760 FLAG_SET_DEFAULT(UseAESIntrinsics, false);
761 }
762 if (UseAESCTRIntrinsics && !FLAG_IS_DEFAULT(UseAESCTRIntrinsics)) {
763 warning("AES-CTR intrinsics are not available on this CPU");
764 FLAG_SET_DEFAULT(UseAESCTRIntrinsics, false);
765 }
766 }
767
768 // Use CLMUL instructions if available.
769 if (supports_clmul()) {
770 if (FLAG_IS_DEFAULT(UseCLMUL)) {
771 UseCLMUL = true;
772 }
773 } else if (UseCLMUL) {
774 if (!FLAG_IS_DEFAULT(UseCLMUL))
775 warning("CLMUL instructions not available on this CPU (AVX may also be required)");
776 FLAG_SET_DEFAULT(UseCLMUL, false);
777 }
778
779 if (UseCLMUL && (UseSSE > 2)) {
780 if (FLAG_IS_DEFAULT(UseCRC32Intrinsics)) {
781 UseCRC32Intrinsics = true;
782 }
783 } else if (UseCRC32Intrinsics) {
784 if (!FLAG_IS_DEFAULT(UseCRC32Intrinsics))
785 warning("CRC32 Intrinsics requires CLMUL instructions (not available on this CPU)");
786 FLAG_SET_DEFAULT(UseCRC32Intrinsics, false);
787 }
788
789 if (supports_sse4_2() && supports_clmul()) {
790 if (FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) {
791 UseCRC32CIntrinsics = true;
792 }
793 } else if (UseCRC32CIntrinsics) {
794 if (!FLAG_IS_DEFAULT(UseCRC32CIntrinsics)) {
795 warning("CRC32C intrinsics are not available on this CPU");
796 }
797 FLAG_SET_DEFAULT(UseCRC32CIntrinsics, false);
798 }
799
800 // GHASH/GCM intrinsics
801 if (UseCLMUL && (UseSSE > 2)) {
802 if (FLAG_IS_DEFAULT(UseGHASHIntrinsics)) {
803 UseGHASHIntrinsics = true;
804 }
805 } else if (UseGHASHIntrinsics) {
806 if (!FLAG_IS_DEFAULT(UseGHASHIntrinsics))
807 warning("GHASH intrinsic requires CLMUL and SSE2 instructions on this CPU");
808 FLAG_SET_DEFAULT(UseGHASHIntrinsics, false);
809 }
810
811 if (supports_fma() && UseSSE >= 2) { // Check UseSSE since FMA code uses SSE instructions
812 if (FLAG_IS_DEFAULT(UseFMA)) {
813 UseFMA = true;
814 }
815 } else if (UseFMA) {
816 warning("FMA instructions are not available on this CPU");
817 FLAG_SET_DEFAULT(UseFMA, false);
818 }
819
820 if (supports_sha() LP64_ONLY(|| supports_avx2() && supports_bmi2())) {
821 if (FLAG_IS_DEFAULT(UseSHA)) {
822 UseSHA = true;
823 }
824 } else if (UseSHA) {
825 warning("SHA instructions are not available on this CPU");
826 FLAG_SET_DEFAULT(UseSHA, false);
827 }
828
829 if (supports_sha() && UseSHA) {
830 if (FLAG_IS_DEFAULT(UseSHA1Intrinsics)) {
831 FLAG_SET_DEFAULT(UseSHA1Intrinsics, true);
832 }
833 } else if (UseSHA1Intrinsics) {
834 warning("Intrinsics for SHA-1 crypto hash functions not available on this CPU.");
835 FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);
836 }
837
838 if (UseSHA) {
839 if (FLAG_IS_DEFAULT(UseSHA256Intrinsics)) {
840 FLAG_SET_DEFAULT(UseSHA256Intrinsics, true);
841 }
842 } else if (UseSHA256Intrinsics) {
843 warning("Intrinsics for SHA-224 and SHA-256 crypto hash functions not available on this CPU.");
844 FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);
845 }
846
847 if (UseSHA) {
848 if (FLAG_IS_DEFAULT(UseSHA512Intrinsics)) {
849 FLAG_SET_DEFAULT(UseSHA512Intrinsics, true);
850 }
851 } else if (UseSHA512Intrinsics) {
852 warning("Intrinsics for SHA-384 and SHA-512 crypto hash functions not available on this CPU.");
853 FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);
854 }
855
856 if (!(UseSHA1Intrinsics || UseSHA256Intrinsics || UseSHA512Intrinsics)) {
857 FLAG_SET_DEFAULT(UseSHA, false);
858 }
859
860 if (UseAdler32Intrinsics) {
861 warning("Adler32Intrinsics not available on this CPU.");
862 FLAG_SET_DEFAULT(UseAdler32Intrinsics, false);
863 }
864
865 if (!supports_rtm() && UseRTMLocking) {
866 // Can't continue because UseRTMLocking affects UseBiasedLocking flag
867 // setting during arguments processing. See use_biased_locking().
868 // VM_Version_init() is executed after UseBiasedLocking is used
869 // in Thread::allocate().
870 vm_exit_during_initialization("RTM instructions are not available on this CPU");
871 }
872
873 #if INCLUDE_RTM_OPT
874 if (UseRTMLocking) {
875 if (is_client_compilation_mode_vm()) {
876 // Only C2 does RTM locking optimization.
877 // Can't continue because UseRTMLocking affects UseBiasedLocking flag
878 // setting during arguments processing. See use_biased_locking().
879 vm_exit_during_initialization("RTM locking optimization is not supported in emulated client VM");
880 }
881 if (is_intel_family_core()) {
882 if ((_model == CPU_MODEL_HASWELL_E3) ||
883 (_model == CPU_MODEL_HASWELL_E7 && _stepping < 3) ||
884 (_model == CPU_MODEL_BROADWELL && _stepping < 4)) {
885 // currently a collision between SKL and HSW_E3
886 if (!UnlockExperimentalVMOptions && UseAVX < 3) {
887 vm_exit_during_initialization("UseRTMLocking is only available as experimental option on this "
888 "platform. It must be enabled via -XX:+UnlockExperimentalVMOptions flag.");
889 } else {
890 warning("UseRTMLocking is only available as experimental option on this platform.");
891 }
892 }
893 }
894 if (!FLAG_IS_CMDLINE(UseRTMLocking)) {
895 // RTM locking should be used only for applications with
896 // high lock contention. For now we do not use it by default.
897 vm_exit_during_initialization("UseRTMLocking flag should be only set on command line");
898 }
899 } else { // !UseRTMLocking
900 if (UseRTMForStackLocks) {
901 if (!FLAG_IS_DEFAULT(UseRTMForStackLocks)) {
902 warning("UseRTMForStackLocks flag should be off when UseRTMLocking flag is off");
903 }
904 FLAG_SET_DEFAULT(UseRTMForStackLocks, false);
905 }
906 if (UseRTMDeopt) {
907 FLAG_SET_DEFAULT(UseRTMDeopt, false);
908 }
909 if (PrintPreciseRTMLockingStatistics) {
910 FLAG_SET_DEFAULT(PrintPreciseRTMLockingStatistics, false);
911 }
912 }
913 #else
914 if (UseRTMLocking) {
915 // Only C2 does RTM locking optimization.
916 // Can't continue because UseRTMLocking affects UseBiasedLocking flag
917 // setting during arguments processing. See use_biased_locking().
918 vm_exit_during_initialization("RTM locking optimization is not supported in this VM");
919 }
920 #endif
921
922 #ifdef COMPILER2
923 if (UseFPUForSpilling) {
924 if (UseSSE < 2) {
925 // Only supported with SSE2+
926 FLAG_SET_DEFAULT(UseFPUForSpilling, false);
927 }
928 }
929 #endif
930 #if defined(COMPILER2) || INCLUDE_JVMCI
931 if (MaxVectorSize > 0) {
932 if (!is_power_of_2(MaxVectorSize)) {
933 warning("MaxVectorSize must be a power of 2");
934 FLAG_SET_DEFAULT(MaxVectorSize, 64);
935 }
936 if (UseSSE < 2) {
937 // Vectors (in XMM) are only supported with SSE2+
938 if (MaxVectorSize > 0) {
939 if (!FLAG_IS_DEFAULT(MaxVectorSize))
940 warning("MaxVectorSize must be 0");
941 FLAG_SET_DEFAULT(MaxVectorSize, 0);
942 }
943 }
944 else if (UseAVX == 0 || !os_supports_avx_vectors()) {
945 // 32 bytes vectors (in YMM) are only supported with AVX+
946 if (MaxVectorSize > 16) {
947 if (!FLAG_IS_DEFAULT(MaxVectorSize))
948 warning("MaxVectorSize must be <= 16");
949 FLAG_SET_DEFAULT(MaxVectorSize, 16);
950 }
951 }
952 else if (UseAVX == 1 || UseAVX == 2) {
953 // 64 bytes vectors (in ZMM) are only supported with AVX 3
954 if (MaxVectorSize > 32) {
955 if (!FLAG_IS_DEFAULT(MaxVectorSize))
956 warning("MaxVectorSize must be <= 32");
957 FLAG_SET_DEFAULT(MaxVectorSize, 32);
958 }
959 }
960 else if (UseAVX > 2 ) {
961 if (MaxVectorSize > 64) {
962 if (!FLAG_IS_DEFAULT(MaxVectorSize))
963 warning("MaxVectorSize must be <= 64");
964 FLAG_SET_DEFAULT(MaxVectorSize, 64);
965 }
966 }
967 #if defined(COMPILER2) && defined(ASSERT)
968 if (supports_avx() && PrintMiscellaneous && Verbose && TraceNewVectors) {
969 tty->print_cr("State of YMM registers after signal handle:");
970 int nreg = 2 LP64_ONLY(+2);
971 const char* ymm_name[4] = {"0", "7", "8", "15"};
972 for (int i = 0; i < nreg; i++) {
973 tty->print("YMM%s:", ymm_name[i]);
974 for (int j = 7; j >=0; j--) {
975 tty->print(" %x", _cpuid_info.ymm_save[i*8 + j]);
976 }
977 tty->cr();
978 }
979 }
980 #endif // COMPILER2 && ASSERT
981 }
982 #endif // COMPILER2 || INCLUDE_JVMCI
983
984 #ifdef COMPILER2
985 #ifdef _LP64
986 if (FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) {
987 UseMultiplyToLenIntrinsic = true;
988 }
989 if (FLAG_IS_DEFAULT(UseSquareToLenIntrinsic)) {
990 UseSquareToLenIntrinsic = true;
991 }
992 if (FLAG_IS_DEFAULT(UseMulAddIntrinsic)) {
993 UseMulAddIntrinsic = true;
994 }
995 if (FLAG_IS_DEFAULT(UseMontgomeryMultiplyIntrinsic)) {
996 UseMontgomeryMultiplyIntrinsic = true;
997 }
998 if (FLAG_IS_DEFAULT(UseMontgomerySquareIntrinsic)) {
999 UseMontgomerySquareIntrinsic = true;
1000 }
1001 #else
1002 if (UseMultiplyToLenIntrinsic) {
1003 if (!FLAG_IS_DEFAULT(UseMultiplyToLenIntrinsic)) {
1004 warning("multiplyToLen intrinsic is not available in 32-bit VM");
1005 }
1006 FLAG_SET_DEFAULT(UseMultiplyToLenIntrinsic, false);
1007 }
1008 if (UseMontgomeryMultiplyIntrinsic) {
1009 if (!FLAG_IS_DEFAULT(UseMontgomeryMultiplyIntrinsic)) {
1010 warning("montgomeryMultiply intrinsic is not available in 32-bit VM");
1011 }
1012 FLAG_SET_DEFAULT(UseMontgomeryMultiplyIntrinsic, false);
1013 }
1014 if (UseMontgomerySquareIntrinsic) {
1015 if (!FLAG_IS_DEFAULT(UseMontgomerySquareIntrinsic)) {
1016 warning("montgomerySquare intrinsic is not available in 32-bit VM");
1017 }
1018 FLAG_SET_DEFAULT(UseMontgomerySquareIntrinsic, false);
1019 }
1020 if (UseSquareToLenIntrinsic) {
1021 if (!FLAG_IS_DEFAULT(UseSquareToLenIntrinsic)) {
1022 warning("squareToLen intrinsic is not available in 32-bit VM");
1023 }
1024 FLAG_SET_DEFAULT(UseSquareToLenIntrinsic, false);
1025 }
1026 if (UseMulAddIntrinsic) {
1027 if (!FLAG_IS_DEFAULT(UseMulAddIntrinsic)) {
1028 warning("mulAdd intrinsic is not available in 32-bit VM");
1029 }
1030 FLAG_SET_DEFAULT(UseMulAddIntrinsic, false);
1031 }
1032 #endif
1033 #endif // COMPILER2
1034
1035 // On new cpus instructions which update whole XMM register should be used
1036 // to prevent partial register stall due to dependencies on high half.
1037 //
1038 // UseXmmLoadAndClearUpper == true --> movsd(xmm, mem)
1039 // UseXmmLoadAndClearUpper == false --> movlpd(xmm, mem)
1040 // UseXmmRegToRegMoveAll == true --> movaps(xmm, xmm), movapd(xmm, xmm).
1041 // UseXmmRegToRegMoveAll == false --> movss(xmm, xmm), movsd(xmm, xmm).
1042
1043 if( is_amd() ) { // AMD cpus specific settings
1044 if( supports_sse2() && FLAG_IS_DEFAULT(UseAddressNop) ) {
1045 // Use it on new AMD cpus starting from Opteron.
1046 UseAddressNop = true;
1047 }
1048 if( supports_sse2() && FLAG_IS_DEFAULT(UseNewLongLShift) ) {
1049 // Use it on new AMD cpus starting from Opteron.
1050 UseNewLongLShift = true;
1051 }
1052 if( FLAG_IS_DEFAULT(UseXmmLoadAndClearUpper) ) {
1053 if (supports_sse4a()) {
1054 UseXmmLoadAndClearUpper = true; // use movsd only on '10h' Opteron
1055 } else {
1056 UseXmmLoadAndClearUpper = false;
1057 }
1058 }
1059 if( FLAG_IS_DEFAULT(UseXmmRegToRegMoveAll) ) {
1060 if( supports_sse4a() ) {
1061 UseXmmRegToRegMoveAll = true; // use movaps, movapd only on '10h'
1062 } else {
1063 UseXmmRegToRegMoveAll = false;
1064 }
1065 }
1066 if( FLAG_IS_DEFAULT(UseXmmI2F) ) {
1067 if( supports_sse4a() ) {
1068 UseXmmI2F = true;
1069 } else {
1070 UseXmmI2F = false;
1071 }
1072 }
1073 if( FLAG_IS_DEFAULT(UseXmmI2D) ) {
1074 if( supports_sse4a() ) {
1075 UseXmmI2D = true;
1076 } else {
1077 UseXmmI2D = false;
1078 }
1079 }
1080 if (supports_sse4_2()) {
1081 if (FLAG_IS_DEFAULT(UseSSE42Intrinsics)) {
1082 FLAG_SET_DEFAULT(UseSSE42Intrinsics, true);
1083 }
1084 } else {
1085 if (UseSSE42Intrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
1086 warning("SSE4.2 intrinsics require SSE4.2 instructions or higher. Intrinsics will be disabled.");
1087 }
1088 FLAG_SET_DEFAULT(UseSSE42Intrinsics, false);
1089 }
1090
1091 // some defaults for AMD family 15h
1092 if ( cpu_family() == 0x15 ) {
1093 // On family 15h processors default is no sw prefetch
1094 if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) {
1095 FLAG_SET_DEFAULT(AllocatePrefetchStyle, 0);
1096 }
1097 // Also, if some other prefetch style is specified, default instruction type is PREFETCHW
1098 if (FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
1099 FLAG_SET_DEFAULT(AllocatePrefetchInstr, 3);
1100 }
1101 // On family 15h processors use XMM and UnalignedLoadStores for Array Copy
1102 if (supports_sse2() && FLAG_IS_DEFAULT(UseXMMForArrayCopy)) {
1103 FLAG_SET_DEFAULT(UseXMMForArrayCopy, true);
1104 }
1105 if (supports_sse2() && FLAG_IS_DEFAULT(UseUnalignedLoadStores)) {
1106 FLAG_SET_DEFAULT(UseUnalignedLoadStores, true);
1107 }
1108 }
1109
1110 #ifdef COMPILER2
1111 if (MaxVectorSize > 16) {
1112 // Limit vectors size to 16 bytes on current AMD cpus.
1113 FLAG_SET_DEFAULT(MaxVectorSize, 16);
1114 }
1115 #endif // COMPILER2
1116 }
1117
1118 if( is_intel() ) { // Intel cpus specific settings
1119 if( FLAG_IS_DEFAULT(UseStoreImmI16) ) {
1120 UseStoreImmI16 = false; // don't use it on Intel cpus
1121 }
1122 if( cpu_family() == 6 || cpu_family() == 15 ) {
1123 if( FLAG_IS_DEFAULT(UseAddressNop) ) {
1124 // Use it on all Intel cpus starting from PentiumPro
1125 UseAddressNop = true;
1126 }
1127 }
1128 if( FLAG_IS_DEFAULT(UseXmmLoadAndClearUpper) ) {
1129 UseXmmLoadAndClearUpper = true; // use movsd on all Intel cpus
1130 }
1131 if( FLAG_IS_DEFAULT(UseXmmRegToRegMoveAll) ) {
1132 if( supports_sse3() ) {
1133 UseXmmRegToRegMoveAll = true; // use movaps, movapd on new Intel cpus
1134 } else {
1135 UseXmmRegToRegMoveAll = false;
1136 }
1137 }
1138 if( cpu_family() == 6 && supports_sse3() ) { // New Intel cpus
1139 #ifdef COMPILER2
1140 if( FLAG_IS_DEFAULT(MaxLoopPad) ) {
1141 // For new Intel cpus do the next optimization:
1142 // don't align the beginning of a loop if there are enough instructions
1143 // left (NumberOfLoopInstrToAlign defined in c2_globals.hpp)
1144 // in current fetch line (OptoLoopAlignment) or the padding
1145 // is big (> MaxLoopPad).
1146 // Set MaxLoopPad to 11 for new Intel cpus to reduce number of
1147 // generated NOP instructions. 11 is the largest size of one
1148 // address NOP instruction '0F 1F' (see Assembler::nop(i)).
1149 MaxLoopPad = 11;
1150 }
1151 #endif // COMPILER2
1152 if (FLAG_IS_DEFAULT(UseXMMForArrayCopy)) {
1153 UseXMMForArrayCopy = true; // use SSE2 movq on new Intel cpus
1154 }
1155 if (supports_sse4_2() && supports_ht()) { // Newest Intel cpus
1156 if (FLAG_IS_DEFAULT(UseUnalignedLoadStores)) {
1157 UseUnalignedLoadStores = true; // use movdqu on newest Intel cpus
1158 }
1159 }
1160 if (supports_sse4_2()) {
1161 if (FLAG_IS_DEFAULT(UseSSE42Intrinsics)) {
1162 FLAG_SET_DEFAULT(UseSSE42Intrinsics, true);
1163 }
1164 } else {
1165 if (UseSSE42Intrinsics && !FLAG_IS_DEFAULT(UseAESIntrinsics)) {
1166 warning("SSE4.2 intrinsics require SSE4.2 instructions or higher. Intrinsics will be disabled.");
1167 }
1168 FLAG_SET_DEFAULT(UseSSE42Intrinsics, false);
1169 }
1170 }
1171 if (is_atom_family() || is_knights_family()) {
1172 #ifdef COMPILER2
1173 if (FLAG_IS_DEFAULT(OptoScheduling)) {
1174 OptoScheduling = true;
1175 }
1176 #endif
1177 if (supports_sse4_2()) { // Silvermont
1178 if (FLAG_IS_DEFAULT(UseUnalignedLoadStores)) {
1179 UseUnalignedLoadStores = true; // use movdqu on newest Intel cpus
1180 }
1181 }
1182 if (FLAG_IS_DEFAULT(UseIncDec)) {
1183 FLAG_SET_DEFAULT(UseIncDec, false);
1184 }
1185 }
1186 if(FLAG_IS_DEFAULT(AllocatePrefetchInstr) && supports_3dnow_prefetch()) {
1187 FLAG_SET_DEFAULT(AllocatePrefetchInstr, 3);
1188 }
1189 }
1190
1191 #ifdef _LP64
1192 if (UseSSE42Intrinsics) {
1193 if (FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic)) {
1194 UseVectorizedMismatchIntrinsic = true;
1195 }
1196 } else if (UseVectorizedMismatchIntrinsic) {
1197 if (!FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic))
1198 warning("vectorizedMismatch intrinsics are not available on this CPU");
1199 FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false);
1200 }
1201 #else
1202 if (UseVectorizedMismatchIntrinsic) {
1203 if (!FLAG_IS_DEFAULT(UseVectorizedMismatchIntrinsic)) {
1204 warning("vectorizedMismatch intrinsic is not available in 32-bit VM");
1205 }
1206 FLAG_SET_DEFAULT(UseVectorizedMismatchIntrinsic, false);
1207 }
1208 #endif // _LP64
1209
1210 // Use count leading zeros count instruction if available.
1211 if (supports_lzcnt()) {
1212 if (FLAG_IS_DEFAULT(UseCountLeadingZerosInstruction)) {
1213 UseCountLeadingZerosInstruction = true;
1214 }
1215 } else if (UseCountLeadingZerosInstruction) {
1216 warning("lzcnt instruction is not available on this CPU");
1217 FLAG_SET_DEFAULT(UseCountLeadingZerosInstruction, false);
1218 }
1219
1220 // Use count trailing zeros instruction if available
1221 if (supports_bmi1()) {
1222 // tzcnt does not require VEX prefix
1223 if (FLAG_IS_DEFAULT(UseCountTrailingZerosInstruction)) {
1224 if (!UseBMI1Instructions && !FLAG_IS_DEFAULT(UseBMI1Instructions)) {
1225 // Don't use tzcnt if BMI1 is switched off on command line.
1226 UseCountTrailingZerosInstruction = false;
1227 } else {
1228 UseCountTrailingZerosInstruction = true;
1229 }
1230 }
1231 } else if (UseCountTrailingZerosInstruction) {
1232 warning("tzcnt instruction is not available on this CPU");
1233 FLAG_SET_DEFAULT(UseCountTrailingZerosInstruction, false);
1234 }
1235
1236 // BMI instructions (except tzcnt) use an encoding with VEX prefix.
1237 // VEX prefix is generated only when AVX > 0.
1238 if (supports_bmi1() && supports_avx()) {
1239 if (FLAG_IS_DEFAULT(UseBMI1Instructions)) {
1240 UseBMI1Instructions = true;
1241 }
1242 } else if (UseBMI1Instructions) {
1243 warning("BMI1 instructions are not available on this CPU (AVX is also required)");
1244 FLAG_SET_DEFAULT(UseBMI1Instructions, false);
1245 }
1246
1247 if (supports_bmi2() && supports_avx()) {
1248 if (FLAG_IS_DEFAULT(UseBMI2Instructions)) {
1249 UseBMI2Instructions = true;
1250 }
1251 } else if (UseBMI2Instructions) {
1252 warning("BMI2 instructions are not available on this CPU (AVX is also required)");
1253 FLAG_SET_DEFAULT(UseBMI2Instructions, false);
1254 }
1255
1256 // Use population count instruction if available.
1257 if (supports_popcnt()) {
1258 if (FLAG_IS_DEFAULT(UsePopCountInstruction)) {
1259 UsePopCountInstruction = true;
1260 }
1261 } else if (UsePopCountInstruction) {
1262 warning("POPCNT instruction is not available on this CPU");
1263 FLAG_SET_DEFAULT(UsePopCountInstruction, false);
1264 }
1265
1266 // Use fast-string operations if available.
1267 if (supports_erms()) {
1268 if (FLAG_IS_DEFAULT(UseFastStosb)) {
1269 UseFastStosb = true;
1270 }
1271 } else if (UseFastStosb) {
1272 warning("fast-string operations are not available on this CPU");
1273 FLAG_SET_DEFAULT(UseFastStosb, false);
1274 }
1275
1276 #ifdef COMPILER2
1277 if (FLAG_IS_DEFAULT(AlignVector)) {
1278 // Modern processors allow misaligned memory operations for vectors.
1279 AlignVector = !UseUnalignedLoadStores;
1280 }
1281 #endif // COMPILER2
1282
1283 if (FLAG_IS_DEFAULT(AllocatePrefetchInstr)) {
1284 if (AllocatePrefetchInstr == 3 && !supports_3dnow_prefetch()) {
1285 FLAG_SET_DEFAULT(AllocatePrefetchInstr, 0);
1286 } else if (!supports_sse() && supports_3dnow_prefetch()) {
1287 FLAG_SET_DEFAULT(AllocatePrefetchInstr, 3);
1288 }
1289 }
1290
1291 // Allocation prefetch settings
1292 intx cache_line_size = prefetch_data_size();
1293 if (FLAG_IS_DEFAULT(AllocatePrefetchStepSize) &&
1294 (cache_line_size > AllocatePrefetchStepSize)) {
1295 FLAG_SET_DEFAULT(AllocatePrefetchStepSize, cache_line_size);
1296 }
1297
1298 if ((AllocatePrefetchDistance == 0) && (AllocatePrefetchStyle != 0)) {
1299 assert(!FLAG_IS_DEFAULT(AllocatePrefetchDistance), "default value should not be 0");
1300 if (!FLAG_IS_DEFAULT(AllocatePrefetchStyle)) {
1301 warning("AllocatePrefetchDistance is set to 0 which disable prefetching. Ignoring AllocatePrefetchStyle flag.");
1302 }
1303 FLAG_SET_DEFAULT(AllocatePrefetchStyle, 0);
1304 }
1305
1306 if (FLAG_IS_DEFAULT(AllocatePrefetchDistance)) {
1307 bool use_watermark_prefetch = (AllocatePrefetchStyle == 2);
1308 FLAG_SET_DEFAULT(AllocatePrefetchDistance, allocate_prefetch_distance(use_watermark_prefetch));
1309 }
1310
1311 if (is_intel() && cpu_family() == 6 && supports_sse3()) {
1312 if (FLAG_IS_DEFAULT(AllocatePrefetchLines) &&
1313 supports_sse4_2() && supports_ht()) { // Nehalem based cpus
1314 FLAG_SET_DEFAULT(AllocatePrefetchLines, 4);
1315 }
1316 #ifdef COMPILER2
1317 if (FLAG_IS_DEFAULT(UseFPUForSpilling) && supports_sse4_2()) {
1318 FLAG_SET_DEFAULT(UseFPUForSpilling, true);
1319 }
1320 #endif
1321 }
1322
1323 #ifdef _LP64
1324 // Prefetch settings
1325
1326 // Prefetch interval for gc copy/scan == 9 dcache lines. Derived from
1327 // 50-warehouse specjbb runs on a 2-way 1.8ghz opteron using a 4gb heap.
1328 // Tested intervals from 128 to 2048 in increments of 64 == one cache line.
1329 // 256 bytes (4 dcache lines) was the nearest runner-up to 576.
1330
1331 // gc copy/scan is disabled if prefetchw isn't supported, because
1332 // Prefetch::write emits an inlined prefetchw on Linux.
1333 // Do not use the 3dnow prefetchw instruction. It isn't supported on em64t.
1334 // The used prefetcht0 instruction works for both amd64 and em64t.
1335
1336 if (FLAG_IS_DEFAULT(PrefetchCopyIntervalInBytes)) {
1337 FLAG_SET_DEFAULT(PrefetchCopyIntervalInBytes, 576);
1338 }
1339 if (FLAG_IS_DEFAULT(PrefetchScanIntervalInBytes)) {
1340 FLAG_SET_DEFAULT(PrefetchScanIntervalInBytes, 576);
1341 }
1342 if (FLAG_IS_DEFAULT(PrefetchFieldsAhead)) {
1343 FLAG_SET_DEFAULT(PrefetchFieldsAhead, 1);
1344 }
1345 #endif
1346
1347 if (FLAG_IS_DEFAULT(ContendedPaddingWidth) &&
1348 (cache_line_size > ContendedPaddingWidth))
1349 ContendedPaddingWidth = cache_line_size;
1350
1351 // This machine allows unaligned memory accesses
1352 if (FLAG_IS_DEFAULT(UseUnalignedAccesses)) {
1353 FLAG_SET_DEFAULT(UseUnalignedAccesses, true);
1354 }
1355
1356 #ifndef PRODUCT
1357 if (log_is_enabled(Info, os, cpu)) {
1358 outputStream* log = Log(os, cpu)::info_stream();
1359 log->print_cr("Logical CPUs per core: %u",
1360 logical_processors_per_package());
1361 log->print_cr("L1 data cache line size: %u", L1_data_cache_line_size());
1362 log->print("UseSSE=%d", (int) UseSSE);
1363 if (UseAVX > 0) {
1364 log->print(" UseAVX=%d", (int) UseAVX);
1365 }
1366 if (UseAES) {
1367 log->print(" UseAES=1");
1368 }
1369 #ifdef COMPILER2
1370 if (MaxVectorSize > 0) {
1371 log->print(" MaxVectorSize=%d", (int) MaxVectorSize);
1372 }
1373 #endif
1374 log->cr();
1375 log->print("Allocation");
1376 if (AllocatePrefetchStyle <= 0 || (UseSSE == 0 && !supports_3dnow_prefetch())) {
1377 log->print_cr(": no prefetching");
1378 } else {
1379 log->print(" prefetching: ");
1380 if (UseSSE == 0 && supports_3dnow_prefetch()) {
1381 log->print("PREFETCHW");
1382 } else if (UseSSE >= 1) {
1383 if (AllocatePrefetchInstr == 0) {
1384 log->print("PREFETCHNTA");
1385 } else if (AllocatePrefetchInstr == 1) {
1386 log->print("PREFETCHT0");
1387 } else if (AllocatePrefetchInstr == 2) {
1388 log->print("PREFETCHT2");
1389 } else if (AllocatePrefetchInstr == 3) {
1390 log->print("PREFETCHW");
1391 }
1392 }
1393 if (AllocatePrefetchLines > 1) {
1394 log->print_cr(" at distance %d, %d lines of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchLines, (int) AllocatePrefetchStepSize);
1395 } else {
1396 log->print_cr(" at distance %d, one line of %d bytes", (int) AllocatePrefetchDistance, (int) AllocatePrefetchStepSize);
1397 }
1398 }
1399
1400 if (PrefetchCopyIntervalInBytes > 0) {
1401 log->print_cr("PrefetchCopyIntervalInBytes %d", (int) PrefetchCopyIntervalInBytes);
1402 }
1403 if (PrefetchScanIntervalInBytes > 0) {
1404 log->print_cr("PrefetchScanIntervalInBytes %d", (int) PrefetchScanIntervalInBytes);
1405 }
1406 if (PrefetchFieldsAhead > 0) {
1407 log->print_cr("PrefetchFieldsAhead %d", (int) PrefetchFieldsAhead);
1408 }
1409 if (ContendedPaddingWidth > 0) {
1410 log->print_cr("ContendedPaddingWidth %d", (int) ContendedPaddingWidth);
1411 }
1412 }
1413 #endif // !PRODUCT
1414 }
1415
1416 bool VM_Version::use_biased_locking() {
1417 #if INCLUDE_RTM_OPT
1418 // RTM locking is most useful when there is high lock contention and
1419 // low data contention. With high lock contention the lock is usually
1420 // inflated and biased locking is not suitable for that case.
1421 // RTM locking code requires that biased locking is off.
1422 // Note: we can't switch off UseBiasedLocking in get_processor_features()
1423 // because it is used by Thread::allocate() which is called before
1424 // VM_Version::initialize().
1425 if (UseRTMLocking && UseBiasedLocking) {
1426 if (FLAG_IS_DEFAULT(UseBiasedLocking)) {
1427 FLAG_SET_DEFAULT(UseBiasedLocking, false);
1428 } else {
1429 warning("Biased locking is not supported with RTM locking; ignoring UseBiasedLocking flag." );
1430 UseBiasedLocking = false;
1431 }
1432 }
1433 #endif
1434 return UseBiasedLocking;
1435 }
1436
1437 void VM_Version::initialize() {
1438 ResourceMark rm;
1439 // Making this stub must be FIRST use of assembler
1440
1441 stub_blob = BufferBlob::create("get_cpu_info_stub", stub_size);
1442 if (stub_blob == NULL) {
1443 vm_exit_during_initialization("Unable to allocate get_cpu_info_stub");
1444 }
1445 CodeBuffer c(stub_blob);
1446 VM_Version_StubGenerator g(&c);
1447 get_cpu_info_stub = CAST_TO_FN_PTR(get_cpu_info_stub_t,
1448 g.generate_get_cpu_info());
1449
1450 get_processor_features();
1451 }