1 /*
   2  * Copyright (c) 1997, 2014, Oracle and/or its affiliates. All rights reserved.
   3  * Copyright 2012, 2014 SAP AG. All rights reserved.
   4  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   5  *
   6  * This code is free software; you can redistribute it and/or modify it
   7  * under the terms of the GNU General Public License version 2 only, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This code is distributed in the hope that it will be useful, but WITHOUT
  11  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  12  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  13  * version 2 for more details (a copy is included in the LICENSE file that
  14  * accompanied this code).
  15  *
  16  * You should have received a copy of the GNU General Public License version
  17  * 2 along with this work; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  19  *
  20  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  21  * or visit www.oracle.com if you need additional information or have any
  22  * questions.
  23  *
  24  */
  25 
  26 #include "precompiled.hpp"
  27 #include "asm/assembler.inline.hpp"
  28 #include "asm/macroAssembler.inline.hpp"
  29 #include "compiler/disassembler.hpp"
  30 #include "memory/resourceArea.hpp"
  31 #include "runtime/java.hpp"
  32 #include "runtime/stubCodeGenerator.hpp"
  33 #include "utilities/defaultStream.hpp"
  34 #include "vm_version_ppc.hpp"
  35 #ifdef TARGET_OS_FAMILY_aix
  36 # include "os_aix.inline.hpp"
  37 #endif
  38 #ifdef TARGET_OS_FAMILY_linux
  39 # include "os_linux.inline.hpp"
  40 #endif
  41 
  42 # include <sys/sysinfo.h>
  43 
  44 int VM_Version::_features = VM_Version::unknown_m;
  45 int VM_Version::_measured_cache_line_size = 128; // default value
  46 const char* VM_Version::_features_str = "";
  47 bool VM_Version::_is_determine_features_test_running = false;
  48 
  49 
  50 #define MSG(flag)   \
  51   if (flag && !FLAG_IS_DEFAULT(flag))                                  \
  52       jio_fprintf(defaultStream::error_stream(),                       \
  53                   "warning: -XX:+" #flag " requires -XX:+UseSIGTRAP\n" \
  54                   "         -XX:+" #flag " will be disabled!\n");
  55 
  56 void VM_Version::initialize() {
  57 
  58   // Test which instructions are supported and measure cache line size.
  59   determine_features();
  60 
  61   // If PowerArchitecturePPC64 hasn't been specified explicitly determine from features.
  62   if (FLAG_IS_DEFAULT(PowerArchitecturePPC64)) {
  63     if (VM_Version::has_popcntw()) {
  64       FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 7);
  65     } else if (VM_Version::has_cmpb()) {
  66       FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 6);
  67     } else if (VM_Version::has_popcntb()) {
  68       FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 5);
  69     } else {
  70       FLAG_SET_ERGO(uintx, PowerArchitecturePPC64, 0);
  71     }
  72   }
  73   guarantee(PowerArchitecturePPC64 == 0 || PowerArchitecturePPC64 == 5 ||
  74             PowerArchitecturePPC64 == 6 || PowerArchitecturePPC64 == 7,
  75             "PowerArchitecturePPC64 should be 0, 5, 6 or 7");
  76 
  77   if (!UseSIGTRAP) {
  78     MSG(TrapBasedICMissChecks);
  79     MSG(TrapBasedNotEntrantChecks);
  80     MSG(TrapBasedNullChecks);
  81     FLAG_SET_ERGO(bool, TrapBasedNotEntrantChecks, false);
  82     FLAG_SET_ERGO(bool, TrapBasedNullChecks,       false);
  83     FLAG_SET_ERGO(bool, TrapBasedICMissChecks,     false);
  84   }
  85 
  86 #ifdef COMPILER2
  87   if (!UseSIGTRAP) {
  88     MSG(TrapBasedRangeChecks);
  89     FLAG_SET_ERGO(bool, TrapBasedRangeChecks, false);
  90   }
  91 
  92   // On Power6 test for section size.
  93   if (PowerArchitecturePPC64 == 6) {
  94     determine_section_size();
  95   // TODO: PPC port } else {
  96   // TODO: PPC port PdScheduling::power6SectorSize = 0x20;
  97   }
  98 
  99   MaxVectorSize = 8;
 100 #endif
 101 
 102   // Create and print feature-string.
 103   char buf[(num_features+1) * 16]; // Max 16 chars per feature.
 104   jio_snprintf(buf, sizeof(buf),
 105                "ppc64%s%s%s%s%s%s%s%s%s",
 106                (has_fsqrt()   ? " fsqrt"   : ""),
 107                (has_isel()    ? " isel"    : ""),
 108                (has_lxarxeh() ? " lxarxeh" : ""),
 109                (has_cmpb()    ? " cmpb"    : ""),
 110                //(has_mftgpr()? " mftgpr"  : ""),
 111                (has_popcntb() ? " popcntb" : ""),
 112                (has_popcntw() ? " popcntw" : ""),
 113                (has_fcfids()  ? " fcfids"  : ""),
 114                (has_vand()    ? " vand"    : ""),
 115                (has_vcipher() ? " aes"     : "")
 116                // Make sure number of %s matches num_features!
 117               );
 118   _features_str = strdup(buf);
 119   NOT_PRODUCT(if (Verbose) print_features(););
 120 
 121   // PPC64 supports 8-byte compare-exchange operations (see
 122   // Atomic::cmpxchg and StubGenerator::generate_atomic_cmpxchg_ptr)
 123   // and 'atomic long memory ops' (see Unsafe_GetLongVolatile).
 124   _supports_cx8 = true;
 125 
 126   UseSSE = 0; // Only on x86 and x64
 127 
 128   intx cache_line_size = _measured_cache_line_size;
 129 
 130   if (FLAG_IS_DEFAULT(AllocatePrefetchStyle)) AllocatePrefetchStyle = 1;
 131 
 132   if (AllocatePrefetchStyle == 4) {
 133     AllocatePrefetchStepSize = cache_line_size; // Need exact value.
 134     if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) AllocatePrefetchLines = 12; // Use larger blocks by default.
 135     if (AllocatePrefetchDistance < 0) AllocatePrefetchDistance = 2*cache_line_size; // Default is not defined?
 136   } else {
 137     if (cache_line_size > AllocatePrefetchStepSize) AllocatePrefetchStepSize = cache_line_size;
 138     if (FLAG_IS_DEFAULT(AllocatePrefetchLines)) AllocatePrefetchLines = 3; // Optimistic value.
 139     if (AllocatePrefetchDistance < 0) AllocatePrefetchDistance = 3*cache_line_size; // Default is not defined?
 140   }
 141 
 142   assert(AllocatePrefetchLines > 0, "invalid value");
 143   if (AllocatePrefetchLines < 1) { // Set valid value in product VM.
 144     AllocatePrefetchLines = 1; // Conservative value.
 145   }
 146 
 147   if (AllocatePrefetchStyle == 3 && AllocatePrefetchDistance < cache_line_size) {
 148     AllocatePrefetchStyle = 1; // Fall back if inappropriate.
 149   }
 150 
 151   assert(AllocatePrefetchStyle >= 0, "AllocatePrefetchStyle should be positive");
 152 
 153   if (UseCRC32Intrinsics) {
 154     if (!FLAG_IS_DEFAULT(UseCRC32Intrinsics))
 155       warning("CRC32 intrinsics  are not available on this CPU");
 156     FLAG_SET_DEFAULT(UseCRC32Intrinsics, false);
 157   }
 158 
 159   // The AES intrinsic stubs require AES instruction support.
 160 #if defined(VM_LITTLE_ENDIAN)
 161   if (has_vcipher()) {
 162     if (FLAG_IS_DEFAULT(UseAES)) {
 163       UseAES = true;
 164     }
 165   } else if (UseAES) {
 166     if (!FLAG_IS_DEFAULT(UseAES))
 167       warning("AES instructions are not available on this CPU");
 168     FLAG_SET_DEFAULT(UseAES, false);
 169   }
 170 
 171   if (UseAES && has_vcipher()) {
 172     if (FLAG_IS_DEFAULT(UseAESIntrinsics)) {
 173       UseAESIntrinsics = true;
 174     }
 175   } else if (UseAESIntrinsics) {
 176     if (!FLAG_IS_DEFAULT(UseAESIntrinsics))
 177       warning("AES intrinsics are not available on this CPU");
 178     FLAG_SET_DEFAULT(UseAESIntrinsics, false);
 179   }
 180 
 181 #else
 182   if (UseAES) {
 183     warning("AES instructions are not available on this CPU");
 184     FLAG_SET_DEFAULT(UseAES, false);
 185   }
 186   if (UseAESIntrinsics) {
 187     if (!FLAG_IS_DEFAULT(UseAESIntrinsics))
 188       warning("AES intrinsics are not available on this CPU");
 189     FLAG_SET_DEFAULT(UseAESIntrinsics, false);
 190   }
 191 #endif
 192 
 193   if (UseSHA) {
 194     warning("SHA instructions are not available on this CPU");
 195     FLAG_SET_DEFAULT(UseSHA, false);
 196   }
 197   if (UseSHA1Intrinsics || UseSHA256Intrinsics || UseSHA512Intrinsics) {
 198     warning("SHA intrinsics are not available on this CPU");
 199     FLAG_SET_DEFAULT(UseSHA1Intrinsics, false);
 200     FLAG_SET_DEFAULT(UseSHA256Intrinsics, false);
 201     FLAG_SET_DEFAULT(UseSHA512Intrinsics, false);
 202   }
 203 
 204 }
 205 
 206 void VM_Version::print_features() {
 207   tty->print_cr("Version: %s cache_line_size = %d", cpu_features(), (int) get_cache_line_size());
 208 }
 209 
 210 #ifdef COMPILER2
 211 // Determine section size on power6: If section size is 8 instructions,
 212 // there should be a difference between the two testloops of ~15 %. If
 213 // no difference is detected the section is assumed to be 32 instructions.
 214 void VM_Version::determine_section_size() {
 215 
 216   int unroll = 80;
 217 
 218   const int code_size = (2* unroll * 32 + 100)*BytesPerInstWord;
 219 
 220   // Allocate space for the code.
 221   ResourceMark rm;
 222   CodeBuffer cb("detect_section_size", code_size, 0);
 223   MacroAssembler* a = new MacroAssembler(&cb);
 224 
 225   uint32_t *code = (uint32_t *)a->pc();
 226   // Emit code.
 227   void (*test1)() = (void(*)())(void *)a->function_entry();
 228 
 229   Label l1;
 230 
 231   a->li(R4, 1);
 232   a->sldi(R4, R4, 28);
 233   a->b(l1);
 234   a->align(CodeEntryAlignment);
 235 
 236   a->bind(l1);
 237 
 238   for (int i = 0; i < unroll; i++) {
 239     // Schleife 1
 240     // ------- sector 0 ------------
 241     // ;; 0
 242     a->nop();                   // 1
 243     a->fpnop0();                // 2
 244     a->fpnop1();                // 3
 245     a->addi(R4,R4, -1); // 4
 246 
 247     // ;;  1
 248     a->nop();                   // 5
 249     a->fmr(F6, F6);             // 6
 250     a->fmr(F7, F7);             // 7
 251     a->endgroup();              // 8
 252     // ------- sector 8 ------------
 253 
 254     // ;;  2
 255     a->nop();                   // 9
 256     a->nop();                   // 10
 257     a->fmr(F8, F8);             // 11
 258     a->fmr(F9, F9);             // 12
 259 
 260     // ;;  3
 261     a->nop();                   // 13
 262     a->fmr(F10, F10);           // 14
 263     a->fmr(F11, F11);           // 15
 264     a->endgroup();              // 16
 265     // -------- sector 16 -------------
 266 
 267     // ;;  4
 268     a->nop();                   // 17
 269     a->nop();                   // 18
 270     a->fmr(F15, F15);           // 19
 271     a->fmr(F16, F16);           // 20
 272 
 273     // ;;  5
 274     a->nop();                   // 21
 275     a->fmr(F17, F17);           // 22
 276     a->fmr(F18, F18);           // 23
 277     a->endgroup();              // 24
 278     // ------- sector 24  ------------
 279 
 280     // ;;  6
 281     a->nop();                   // 25
 282     a->nop();                   // 26
 283     a->fmr(F19, F19);           // 27
 284     a->fmr(F20, F20);           // 28
 285 
 286     // ;;  7
 287     a->nop();                   // 29
 288     a->fmr(F21, F21);           // 30
 289     a->fmr(F22, F22);           // 31
 290     a->brnop0();                // 32
 291 
 292     // ------- sector 32 ------------
 293   }
 294 
 295   // ;; 8
 296   a->cmpdi(CCR0, R4, unroll);   // 33
 297   a->bge(CCR0, l1);             // 34
 298   a->blr();
 299 
 300   // Emit code.
 301   void (*test2)() = (void(*)())(void *)a->function_entry();
 302   // uint32_t *code = (uint32_t *)a->pc();
 303 
 304   Label l2;
 305 
 306   a->li(R4, 1);
 307   a->sldi(R4, R4, 28);
 308   a->b(l2);
 309   a->align(CodeEntryAlignment);
 310 
 311   a->bind(l2);
 312 
 313   for (int i = 0; i < unroll; i++) {
 314     // Schleife 2
 315     // ------- sector 0 ------------
 316     // ;; 0
 317     a->brnop0();                  // 1
 318     a->nop();                     // 2
 319     //a->cmpdi(CCR0, R4, unroll);
 320     a->fpnop0();                  // 3
 321     a->fpnop1();                  // 4
 322     a->addi(R4,R4, -1);           // 5
 323 
 324     // ;; 1
 325 
 326     a->nop();                     // 6
 327     a->fmr(F6, F6);               // 7
 328     a->fmr(F7, F7);               // 8
 329     // ------- sector 8 ---------------
 330 
 331     // ;; 2
 332     a->endgroup();                // 9
 333 
 334     // ;; 3
 335     a->nop();                     // 10
 336     a->nop();                     // 11
 337     a->fmr(F8, F8);               // 12
 338 
 339     // ;; 4
 340     a->fmr(F9, F9);               // 13
 341     a->nop();                     // 14
 342     a->fmr(F10, F10);             // 15
 343 
 344     // ;; 5
 345     a->fmr(F11, F11);             // 16
 346     // -------- sector 16 -------------
 347 
 348     // ;; 6
 349     a->endgroup();                // 17
 350 
 351     // ;; 7
 352     a->nop();                     // 18
 353     a->nop();                     // 19
 354     a->fmr(F15, F15);             // 20
 355 
 356     // ;; 8
 357     a->fmr(F16, F16);             // 21
 358     a->nop();                     // 22
 359     a->fmr(F17, F17);             // 23
 360 
 361     // ;; 9
 362     a->fmr(F18, F18);             // 24
 363     // -------- sector 24 -------------
 364 
 365     // ;; 10
 366     a->endgroup();                // 25
 367 
 368     // ;; 11
 369     a->nop();                     // 26
 370     a->nop();                     // 27
 371     a->fmr(F19, F19);             // 28
 372 
 373     // ;; 12
 374     a->fmr(F20, F20);             // 29
 375     a->nop();                     // 30
 376     a->fmr(F21, F21);             // 31
 377 
 378     // ;; 13
 379     a->fmr(F22, F22);             // 32
 380   }
 381 
 382   // -------- sector 32 -------------
 383   // ;; 14
 384   a->cmpdi(CCR0, R4, unroll); // 33
 385   a->bge(CCR0, l2);           // 34
 386 
 387   a->blr();
 388   uint32_t *code_end = (uint32_t *)a->pc();
 389   a->flush();
 390 
 391   double loop1_seconds,loop2_seconds, rel_diff;
 392   uint64_t start1, stop1;
 393 
 394   start1 = os::current_thread_cpu_time(false);
 395   (*test1)();
 396   stop1 = os::current_thread_cpu_time(false);
 397   loop1_seconds = (stop1- start1) / (1000 *1000 *1000.0);
 398 
 399 
 400   start1 = os::current_thread_cpu_time(false);
 401   (*test2)();
 402   stop1 = os::current_thread_cpu_time(false);
 403 
 404   loop2_seconds = (stop1 - start1) / (1000 *1000 *1000.0);
 405 
 406   rel_diff = (loop2_seconds - loop1_seconds) / loop1_seconds *100;
 407 
 408   if (PrintAssembly) {
 409     ttyLocker ttyl;
 410     tty->print_cr("Decoding section size detection stub at " INTPTR_FORMAT " before execution:", p2i(code));
 411     Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
 412     tty->print_cr("Time loop1 :%f", loop1_seconds);
 413     tty->print_cr("Time loop2 :%f", loop2_seconds);
 414     tty->print_cr("(time2 - time1) / time1 = %f %%", rel_diff);
 415 
 416     if (rel_diff > 12.0) {
 417       tty->print_cr("Section Size 8 Instructions");
 418     } else{
 419       tty->print_cr("Section Size 32 Instructions or Power5");
 420     }
 421   }
 422 
 423 #if 0 // TODO: PPC port
 424   // Set sector size (if not set explicitly).
 425   if (FLAG_IS_DEFAULT(Power6SectorSize128PPC64)) {
 426     if (rel_diff > 12.0) {
 427       PdScheduling::power6SectorSize = 0x20;
 428     } else {
 429       PdScheduling::power6SectorSize = 0x80;
 430     }
 431   } else if (Power6SectorSize128PPC64) {
 432     PdScheduling::power6SectorSize = 0x80;
 433   } else {
 434     PdScheduling::power6SectorSize = 0x20;
 435   }
 436 #endif
 437   if (UsePower6SchedulerPPC64) Unimplemented();
 438 }
 439 #endif // COMPILER2
 440 
 441 void VM_Version::determine_features() {
 442 #if defined(ABI_ELFv2)
 443   const int code_size = (num_features+1+2*7)*BytesPerInstWord; // TODO(asmundak): calculation is incorrect.
 444 #else
 445   // 7 InstWords for each call (function descriptor + blr instruction).
 446   const int code_size = (num_features+1+2*7)*BytesPerInstWord;
 447 #endif
 448   int features = 0;
 449 
 450   // create test area
 451   enum { BUFFER_SIZE = 2*4*K }; // Needs to be >=2* max cache line size (cache line size can't exceed min page size).
 452   char test_area[BUFFER_SIZE];
 453   char *mid_of_test_area = &test_area[BUFFER_SIZE>>1];
 454 
 455   // Allocate space for the code.
 456   ResourceMark rm;
 457   CodeBuffer cb("detect_cpu_features", code_size, 0);
 458   MacroAssembler* a = new MacroAssembler(&cb);
 459 
 460   // Must be set to true so we can generate the test code.
 461   _features = VM_Version::all_features_m;
 462 
 463   // Emit code.
 464   void (*test)(address addr, uint64_t offset)=(void(*)(address addr, uint64_t offset))(void *)a->function_entry();
 465   uint32_t *code = (uint32_t *)a->pc();
 466   // Don't use R0 in ldarx.
 467   // Keep R3_ARG1 unmodified, it contains &field (see below).
 468   // Keep R4_ARG2 unmodified, it contains offset = 0 (see below).
 469   a->fsqrt(F3, F4);                            // code[0] -> fsqrt_m
 470   a->fsqrts(F3, F4);                           // code[1] -> fsqrts_m
 471   a->isel(R7, R5, R6, 0);                      // code[2] -> isel_m
 472   a->ldarx_unchecked(R7, R3_ARG1, R4_ARG2, 1); // code[3] -> lxarx_m
 473   a->cmpb(R7, R5, R6);                         // code[4] -> bcmp
 474   //a->mftgpr(R7, F3);                         // code[5] -> mftgpr
 475   a->popcntb(R7, R5);                          // code[6] -> popcntb
 476   a->popcntw(R7, R5);                          // code[7] -> popcntw
 477   a->fcfids(F3, F4);                           // code[8] -> fcfids
 478   a->vand(VR0, VR0, VR0);                      // code[9] -> vand
 479   a->vcipher(VR0, VR1, VR2);                   // code[10] -> vcipher
 480   a->blr();
 481 
 482   // Emit function to set one cache line to zero. Emit function descriptor and get pointer to it.
 483   void (*zero_cacheline_func_ptr)(char*) = (void(*)(char*))(void *)a->function_entry();
 484   a->dcbz(R3_ARG1); // R3_ARG1 = addr
 485   a->blr();
 486 
 487   uint32_t *code_end = (uint32_t *)a->pc();
 488   a->flush();
 489   _features = VM_Version::unknown_m;
 490 
 491   // Print the detection code.
 492   if (PrintAssembly) {
 493     ttyLocker ttyl;
 494     tty->print_cr("Decoding cpu-feature detection stub at " INTPTR_FORMAT " before execution:", p2i(code));
 495     Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
 496   }
 497 
 498   // Measure cache line size.
 499   memset(test_area, 0xFF, BUFFER_SIZE); // Fill test area with 0xFF.
 500   (*zero_cacheline_func_ptr)(mid_of_test_area); // Call function which executes dcbz to the middle.
 501   int count = 0; // count zeroed bytes
 502   for (int i = 0; i < BUFFER_SIZE; i++) if (test_area[i] == 0) count++;
 503   guarantee(is_power_of_2(count), "cache line size needs to be a power of 2");
 504   _measured_cache_line_size = count;
 505 
 506   // Execute code. Illegal instructions will be replaced by 0 in the signal handler.
 507   VM_Version::_is_determine_features_test_running = true;
 508   (*test)((address)mid_of_test_area, (uint64_t)0);
 509   VM_Version::_is_determine_features_test_running = false;
 510 
 511   // determine which instructions are legal.
 512   int feature_cntr = 0;
 513   if (code[feature_cntr++]) features |= fsqrt_m;
 514   if (code[feature_cntr++]) features |= fsqrts_m;
 515   if (code[feature_cntr++]) features |= isel_m;
 516   if (code[feature_cntr++]) features |= lxarxeh_m;
 517   if (code[feature_cntr++]) features |= cmpb_m;
 518   //if(code[feature_cntr++])features |= mftgpr_m;
 519   if (code[feature_cntr++]) features |= popcntb_m;
 520   if (code[feature_cntr++]) features |= popcntw_m;
 521   if (code[feature_cntr++]) features |= fcfids_m;
 522   if (code[feature_cntr++]) features |= vand_m;
 523   if (code[feature_cntr++]) features |= vcipher_m;
 524 
 525   // Print the detection code.
 526   if (PrintAssembly) {
 527     ttyLocker ttyl;
 528     tty->print_cr("Decoding cpu-feature detection stub at " INTPTR_FORMAT " after execution:", p2i(code));
 529     Disassembler::decode((u_char*)code, (u_char*)code_end, tty);
 530   }
 531 
 532   _features = features;
 533 }
 534 
 535 
 536 static int saved_features = 0;
 537 
 538 void VM_Version::allow_all() {
 539   saved_features = _features;
 540   _features      = all_features_m;
 541 }
 542 
 543 void VM_Version::revert() {
 544   _features = saved_features;
 545 }