src/gromacs/gmxlib/gmx_cpuid.c

   1 /*
   2  * This file is part of the GROMACS molecular simulation package.
   3  *
   4  * Copyright (c) 2012,2013,2014,2015,2016, by the GROMACS development team, led by
   5  * Mark Abraham, David van der Spoel, Berk Hess, and Erik Lindahl,
   6  * and including many others, as listed in the AUTHORS file in the
   7  * top-level source directory and at http://www.gromacs.org.
   8  *
   9  * GROMACS is free software; you can redistribute it and/or
  10  * modify it under the terms of the GNU Lesser General Public License
  11  * as published by the Free Software Foundation; either version 2.1
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  34  */
  35 #include "gmxpre.h"
  36
  37 /*! \cond */
  38 #include "gromacs/legacyheaders/gmx_cpuid.h"
  39
  40 #ifdef HAVE_CONFIG_H
  41 #include "config.h"
  42 #endif
  43
  44 #include <ctype.h>
  45 #include <stdio.h>
  46 #include <stdlib.h>
  47 #include <string.h>
  48
  49 #ifdef GMX_NATIVE_WINDOWS
  50 /* MSVC definition for __cpuid() */
  51     #ifdef _MSC_VER
  52         #include <intrin.h>
  53     #endif
  54 /* sysinfo functions */
  55     #include <windows.h>
  56 #endif
  57 #ifdef HAVE_SCHED_H
  58     #include <sched.h>
  59 #endif
  60 #ifdef HAVE_UNISTD_H
  61 /* sysconf() definition */
  62     #include <unistd.h>
  63 #endif
  64
  65
  66 /* For convenience, and to enable configure-time invocation, we keep all architectures
  67  * in a single file, but to avoid repeated ifdefs we set the overall architecture here.
  68  */
  69 #ifdef GMX_TARGET_X86
  70 /* OK, it is x86, but can we execute cpuid? */
  71 #if defined(GMX_X86_GCC_INLINE_ASM) || ( defined(_MSC_VER) && ( (_MSC_VER > 1500) || (_MSC_VER == 1500 & _MSC_FULL_VER >= 150030729)))
  72 #    define GMX_CPUID_X86
  73 #endif
  74 #endif
  75
  76 /* Global constant character strings corresponding to our enumerated types */
  77 const char *
  78 gmx_cpuid_vendor_string[GMX_CPUID_NVENDORS] =
  79 {
  80     "CannotDetect",
  81     "Unknown",
  82     "GenuineIntel",
  83     "AuthenticAMD",
  84     "Fujitsu",
  85     "IBM", /* Used on Power and BlueGene/Q */
  86     "ARM"
  87 };
  88
  89 const char *
  90 gmx_cpuid_vendor_string_alternative[GMX_CPUID_NVENDORS] =
  91 {
  92     "CannotDetect",
  93     "Unknown",
  94     "GenuineIntel",
  95     "AuthenticAMD",
  96     "Fujitsu",
  97     "ibm", /* Used on Power and BlueGene/Q */
  98     "AArch64"
  99 };
 100
 101 const char *
 102 gmx_cpuid_feature_string[GMX_CPUID_NFEATURES] =
 103 {
 104     "CannotDetect",
 105     "aes",
 106     "apic",
 107     "avx",
 108     "avx2",
 109     "avx512f",
 110     "avx512pf",
 111     "avx512er",
 112     "avx512cd",
 113     "clfsh",
 114     "cmov",
 115     "cx8",
 116     "cx16",
 117     "f16c",
 118     "fma",
 119     "fma4",
 120     "htt",
 121     "lahf_lm",
 122     "misalignsse",
 123     "mmx",
 124     "msr",
 125     "nonstop_tsc",
 126     "pcid",
 127     "pclmuldq",
 128     "pdcm",
 129     "pdpe1gb",
 130     "popcnt",
 131     "pse",
 132     "rdrnd",
 133     "rdtscp",
 134     "sse2",
 135     "sse3",
 136     "sse4a",
 137     "sse4.1",
 138     "sse4.2",
 139     "ssse3",
 140     "tdt",
 141     "x2apic",
 142     "xop",
 143     "arm_neon",
 144     "arm_neon_asimd",
 145     "QPX",
 146     "VMX",
 147     "VSX"
 148 };
 149
 150 const char *
 151 gmx_cpuid_simd_string[GMX_CPUID_NSIMD] =
 152 {
 153     "CannotDetect",
 154     "None",
 155     "Reference",
 156     "SSE2",
 157     "SSE4.1",
 158     "AVX_128_FMA",
 159     "AVX_256",
 160     "AVX2_256",
 161     "AVX_512F",
 162     "AVX_512ER",
 163     "Sparc64 HPC-ACE",
 164     "IBM_QPX",
 165     "IBM_VMX",
 166     "IBM_VSX",
 167     "ARM_NEON",
 168     "ARM_NEON_ASIMD"
 169 };
 170
 171 /* Max length of brand string */
 172 #define GMX_CPUID_STRLEN 256
 173
 174
 175 /* Contents of the abstract datatype */
 176 struct gmx_cpuid
 177 {
 178     enum gmx_cpuid_vendor      vendor;
 179     char                       brand[GMX_CPUID_STRLEN];
 180     int                        family;
 181     int                        model;
 182     int                        stepping;
 183     /* Not using gmx_bool here, since this file must be possible to compile without simple.h */
 184     char                       feature[GMX_CPUID_NFEATURES];
 185
 186     /* Basic CPU topology information. For x86 this is a bit complicated since the topology differs between
 187      * operating systems and sometimes even settings. For most other architectures you can likely just check
 188      * the documentation and then write static information to these arrays rather than detecting on-the-fly.
 189      */
 190     int                        have_cpu_topology;
 191     int                        nproc;               /* total number of logical processors from OS */
 192     int                        npackages;
 193     int                        ncores_per_package;
 194     int                        nhwthreads_per_core;
 195     int *                      package_id;
 196     int *                      core_id;             /* Local core id in each package */
 197     int *                      hwthread_id;         /* Local hwthread id in each core */
 198     int *                      locality_order;      /* Processor indices sorted in locality order */
 199 };
 200
 201
 202 /* Simple routines to access the data structure. The initialization routine is
 203  * further down since that needs to call other static routines in this file.
 204  */
 205 enum gmx_cpuid_vendor
 206 gmx_cpuid_vendor            (gmx_cpuid_t                cpuid)
 207 {
 208     return cpuid->vendor;
 209 }
 210
 211
 212 const char *
 213 gmx_cpuid_brand             (gmx_cpuid_t                cpuid)
 214 {
 215     return cpuid->brand;
 216 }
 217
 218 int
 219 gmx_cpuid_family            (gmx_cpuid_t                cpuid)
 220 {
 221     return cpuid->family;
 222 }
 223
 224 int
 225 gmx_cpuid_model             (gmx_cpuid_t                cpuid)
 226 {
 227     return cpuid->model;
 228 }
 229
 230 int
 231 gmx_cpuid_stepping          (gmx_cpuid_t                cpuid)
 232 {
 233     return cpuid->stepping;
 234 }
 235
 236 int
 237 gmx_cpuid_feature           (gmx_cpuid_t                cpuid,
 238                              enum gmx_cpuid_feature     feature)
 239 {
 240     return (cpuid->feature[feature] != 0);
 241 }
 242
 243
 244 int
 245 gmx_cpuid_is_intel_nehalem  (const gmx_cpuid_t          cpuid)
 246 {
 247     return (cpuid->vendor == GMX_CPUID_VENDOR_INTEL &&
 248             cpuid->family == 6 &&
 249             (cpuid->model == 0x2E ||
 250              cpuid->model == 0x1A ||
 251              cpuid->model == 0x1E ||
 252              cpuid->model == 0x2F ||
 253              cpuid->model == 0x2C ||
 254              cpuid->model == 0x25));
 255 }
 256
 257
 258 /* What type of SIMD was compiled in, if any? */
 259 #ifdef GMX_SIMD_X86_AVX_512ER
 260 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_AVX_512ER;
 261 #elif defined GMX_SIMD_X86_AVX_512F
 262 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_AVX_512F;
 263 #elif defined GMX_SIMD_X86_AVX2_256
 264 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_AVX2_256;
 265 #elif defined GMX_SIMD_X86_AVX_256
 266 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_AVX_256;
 267 #elif defined GMX_SIMD_X86_AVX_128_FMA
 268 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_AVX_128_FMA;
 269 #elif defined GMX_SIMD_X86_SSE4_1
 270 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_SSE4_1;
 271 #elif defined GMX_SIMD_X86_SSE2
 272 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_X86_SSE2;
 273 #elif defined GMX_SIMD_ARM_NEON
 274 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_ARM_NEON;
 275 #elif defined GMX_SIMD_ARM_NEON_ASIMD
 276 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_ARM_NEON_ASIMD;
 277 #elif defined GMX_SIMD_SPARC64_HPC_ACE
 278 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_SPARC64_HPC_ACE;
 279 #elif defined GMX_SIMD_IBM_QPX
 280 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_IBM_QPX;
 281 #elif defined GMX_SIMD_IBM_VMX
 282 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_IBM_VMX;
 283 #elif defined GMX_SIMD_IBM_VSX
 284 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_IBM_VSX;
 285 #elif defined GMX_SIMD_REFERENCE
 286 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_REFERENCE;
 287 #else
 288 static const enum gmx_cpuid_simd compiled_simd = GMX_CPUID_SIMD_NONE;
 289 #endif
 290
 291
 292 enum gmx_cpuid_simd
 293 gmx_compiled_simd()
 294 {
 295     return compiled_simd;
 296 }
 297
 298
 299 #ifdef GMX_CPUID_X86
 300
 301 /* Execute CPUID on x86 class CPUs. level sets function to exec, and the
 302  * contents of register output is returned. See Intel/AMD docs for details.
 303  *
 304  * This version supports extended information where we can also have an input
 305  * value in the ecx register. This is ignored for most levels, but some of them
 306  * (e.g. level 0xB on Intel) use it.
 307  */
 308 static int
 309 execute_x86cpuid(unsigned int   level,
 310                  unsigned int   ecxval,
 311                  unsigned int * eax,
 312                  unsigned int * ebx,
 313                  unsigned int * ecx,
 314                  unsigned int * edx)
 315 {
 316     int rc = 0;
 317
 318     /* Currently CPUID is only supported (1) if we can use an instruction on MSVC, or (2)
 319      * if the compiler handles GNU-style inline assembly.
 320      */
 321
 322 #if (defined _MSC_VER)
 323     int CPUInfo[4];
 324
 325 #if (_MSC_VER > 1500) || (_MSC_VER == 1500 & _MSC_FULL_VER >= 150030729)
 326     /* MSVC 9.0 SP1 or later */
 327     __cpuidex(CPUInfo, level, ecxval);
 328     rc = 0;
 329 #else
 330     __cpuid(CPUInfo, level);
 331     /* Set an error code if the user wanted a non-zero ecxval, since we did not have cpuidex */
 332     rc = (ecxval > 0) ? -1 : 0;
 333 #endif
 334     *eax = CPUInfo[0];
 335     *ebx = CPUInfo[1];
 336     *ecx = CPUInfo[2];
 337     *edx = CPUInfo[3];
 338
 339 #elif (defined GMX_X86_GCC_INLINE_ASM)
 340     /* for now this means GMX_X86_GCC_INLINE_ASM should be defined,
 341      * but there might be more options added in the future.
 342      */
 343     *eax = level;
 344     *ecx = ecxval;
 345     *ebx = 0;
 346     *edx = 0;
 347 #if defined(__i386__) && defined(__PIC__)
 348     /* Avoid clobbering the global offset table in 32-bit pic code (ebx register) */
 349     __asm__ __volatile__ ("xchgl %%ebx, %1  \n\t"
 350                           "cpuid            \n\t"
 351                           "xchgl %%ebx, %1  \n\t"
 352                           : "+a" (*eax), "+r" (*ebx), "+c" (*ecx), "+d" (*edx));
 353 #else
 354     /* i386 without PIC, or x86-64. Things are easy and we can clobber any reg we want :-) */
 355     __asm__ __volatile__ ("cpuid            \n\t"
 356                           : "+a" (*eax), "+b" (*ebx), "+c" (*ecx), "+d" (*edx));
 357 #endif
 358     rc = 0;
 359 #else
 360     /* Death and horror!
 361      * Apparently this is an x86 platform where we don't know how to call cpuid.
 362      *
 363      * This is REALLY bad, since we will lose all Gromacs SIMD support.
 364      */
 365     *eax = 0;
 366     *ebx = 0;
 367     *ecx = 0;
 368     *edx = 0;
 369
 370     rc = -1;
 371 #endif
 372     return rc;
 373 }
 374
 375
 376 /* Identify CPU features common to Intel & AMD - mainly brand string,
 377  * version and some features. Vendor has already been detected outside this.
 378  */
 379 static int
 380 cpuid_check_common_x86(gmx_cpuid_t                cpuid)
 381 {
 382     int                       fn, max_stdfn, max_extfn;
 383     unsigned int              eax, ebx, ecx, edx;
 384     char                      str[GMX_CPUID_STRLEN];
 385     char *                    p;
 386
 387     /* Find largest standard/extended function input value */
 388     execute_x86cpuid(0x0, 0, &eax, &ebx, &ecx, &edx);
 389     max_stdfn = eax;
 390     execute_x86cpuid(0x80000000, 0, &eax, &ebx, &ecx, &edx);
 391     max_extfn = eax;
 392
 393     p = str;
 394     if (max_extfn >= 0x80000005)
 395     {
 396         /* Get CPU brand string */
 397         for (fn = 0x80000002; fn < 0x80000005; fn++)
 398         {
 399             execute_x86cpuid(fn, 0, &eax, &ebx, &ecx, &edx);
 400             memcpy(p, &eax, 4);
 401             memcpy(p+4, &ebx, 4);
 402             memcpy(p+8, &ecx, 4);
 403             memcpy(p+12, &edx, 4);
 404             p += 16;
 405         }
 406         *p = '\0';
 407
 408         /* Remove empty initial space */
 409         p = str;
 410         while (isspace(*(p)))
 411         {
 412             p++;
 413         }
 414         strncpy(cpuid->brand, p, GMX_CPUID_STRLEN);
 415     }
 416     else
 417     {
 418         strncpy(cpuid->brand, "Unknown CPU brand", GMX_CPUID_STRLEN);
 419     }
 420
 421     /* Find basic CPU properties */
 422     if (max_stdfn >= 1)
 423     {
 424         execute_x86cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
 425
 426         cpuid->family   = ((eax & 0x0FF00000) >> 20) + ((eax & 0x00000F00) >> 8);
 427         /* Note that extended model should be shifted left 4, so only shift right 12 iso 16. */
 428         cpuid->model    = ((eax & 0x000F0000) >> 12) + ((eax & 0x000000F0) >> 4);
 429         cpuid->stepping = (eax & 0x0000000F);
 430
 431         /* Feature flags common to AMD and intel */
 432         cpuid->feature[GMX_CPUID_FEATURE_X86_SSE3]     = (ecx & (1 << 0))  != 0;
 433         cpuid->feature[GMX_CPUID_FEATURE_X86_PCLMULDQ] = (ecx & (1 << 1))  != 0;
 434         cpuid->feature[GMX_CPUID_FEATURE_X86_SSSE3]    = (ecx & (1 << 9))  != 0;
 435         cpuid->feature[GMX_CPUID_FEATURE_X86_FMA]      = (ecx & (1 << 12)) != 0;
 436         cpuid->feature[GMX_CPUID_FEATURE_X86_CX16]     = (ecx & (1 << 13)) != 0;
 437         cpuid->feature[GMX_CPUID_FEATURE_X86_SSE4_1]   = (ecx & (1 << 19)) != 0;
 438         cpuid->feature[GMX_CPUID_FEATURE_X86_SSE4_2]   = (ecx & (1 << 20)) != 0;
 439         cpuid->feature[GMX_CPUID_FEATURE_X86_POPCNT]   = (ecx & (1 << 23)) != 0;
 440         cpuid->feature[GMX_CPUID_FEATURE_X86_AES]      = (ecx & (1 << 25)) != 0;
 441         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX]      = (ecx & (1 << 28)) != 0;
 442         cpuid->feature[GMX_CPUID_FEATURE_X86_F16C]     = (ecx & (1 << 29)) != 0;
 443         cpuid->feature[GMX_CPUID_FEATURE_X86_RDRND]    = (ecx & (1 << 30)) != 0;
 444
 445         cpuid->feature[GMX_CPUID_FEATURE_X86_PSE]      = (edx & (1 << 3))  != 0;
 446         cpuid->feature[GMX_CPUID_FEATURE_X86_MSR]      = (edx & (1 << 5))  != 0;
 447         cpuid->feature[GMX_CPUID_FEATURE_X86_CX8]      = (edx & (1 << 8))  != 0;
 448         cpuid->feature[GMX_CPUID_FEATURE_X86_APIC]     = (edx & (1 << 9))  != 0;
 449         cpuid->feature[GMX_CPUID_FEATURE_X86_CMOV]     = (edx & (1 << 15)) != 0;
 450         cpuid->feature[GMX_CPUID_FEATURE_X86_CLFSH]    = (edx & (1 << 19)) != 0;
 451         cpuid->feature[GMX_CPUID_FEATURE_X86_MMX]      = (edx & (1 << 23)) != 0;
 452         cpuid->feature[GMX_CPUID_FEATURE_X86_SSE2]     = (edx & (1 << 26)) != 0;
 453         cpuid->feature[GMX_CPUID_FEATURE_X86_HTT]      = (edx & (1 << 28)) != 0;
 454     }
 455     else
 456     {
 457         cpuid->family   = -1;
 458         cpuid->model    = -1;
 459         cpuid->stepping = -1;
 460     }
 461
 462     if (max_extfn >= 0x80000001)
 463     {
 464         execute_x86cpuid(0x80000001, 0, &eax, &ebx, &ecx, &edx);
 465         cpuid->feature[GMX_CPUID_FEATURE_X86_LAHF_LM] = (ecx & (1 << 0))  != 0;
 466         cpuid->feature[GMX_CPUID_FEATURE_X86_PDPE1GB] = (edx & (1 << 26)) != 0;
 467         cpuid->feature[GMX_CPUID_FEATURE_X86_RDTSCP]  = (edx & (1 << 27)) != 0;
 468     }
 469
 470     if (max_extfn >= 0x80000007)
 471     {
 472         execute_x86cpuid(0x80000007, 0, &eax, &ebx, &ecx, &edx);
 473         cpuid->feature[GMX_CPUID_FEATURE_X86_NONSTOP_TSC]  = (edx & (1 << 8))  != 0;
 474     }
 475     return 0;
 476 }
 477
 478 /* This routine returns the number of unique different elements found in the array,
 479  * and renumbers these starting from 0. For example, the array {0,1,2,8,9,10,8,9,10,0,1,2}
 480  * will be rewritten to {0,1,2,3,4,5,3,4,5,0,1,2}, and it returns 6 for the
 481  * number of unique elements.
 482  */
 483 static int
 484 cpuid_renumber_elements(int *data, int n)
 485 {
 486     int *unique;
 487     int  i, j, nunique, found;
 488
 489     unique = malloc(sizeof(int)*n);
 490
 491     nunique = 0;
 492     for (i = 0; i < n; i++)
 493     {
 494         for (j = 0, found = 0; j < nunique && !found; j++)
 495         {
 496             found = (data[i] == unique[j]);
 497         }
 498         if (!found)
 499         {
 500             /* Insert in sorted order! */
 501             for (j = nunique++; j > 0 && unique[j-1] > data[i]; j--)
 502             {
 503                 unique[j] = unique[j-1];
 504             }
 505             unique[j] = data[i];
 506         }
 507     }
 508     /* renumber */
 509     for (i = 0; i < n; i++)
 510     {
 511         for (j = 0; j < nunique; j++)
 512         {
 513             if (data[i] == unique[j])
 514             {
 515                 data[i] = j;
 516             }
 517         }
 518     }
 519     free(unique);
 520     return nunique;
 521 }
 522
 523 /* APIC IDs, or everything you wanted to know about your x86 cores but were afraid to ask...
 524  *
 525  * Raw APIC IDs are unfortunately somewhat dirty. For technical reasons they are assigned
 526  * in power-of-2 chunks, and even then there are no guarantees about specific numbers - all
 527  * we know is that the part for each thread/core/package is unique, and how many bits are
 528  * reserved for that part.
 529  * This routine does internal renumbering so we get continuous indices, and also
 530  * decodes the actual number of packages,cores-per-package and hwthreads-per-core.
 531  * Returns: 0 on success, non-zero on failure.
 532  */
 533 static int
 534 cpuid_x86_decode_apic_id(gmx_cpuid_t cpuid, int *apic_id, int core_bits, int hwthread_bits)
 535 {
 536     int i, idx;
 537     int hwthread_mask, core_mask_after_shift;
 538
 539     cpuid->hwthread_id     = malloc(sizeof(int)*cpuid->nproc);
 540     cpuid->core_id         = malloc(sizeof(int)*cpuid->nproc);
 541     cpuid->package_id      = malloc(sizeof(int)*cpuid->nproc);
 542     cpuid->locality_order  = malloc(sizeof(int)*cpuid->nproc);
 543
 544     hwthread_mask         = (1 << hwthread_bits) - 1;
 545     core_mask_after_shift = (1 << core_bits) - 1;
 546
 547     for (i = 0; i < cpuid->nproc; i++)
 548     {
 549         cpuid->hwthread_id[i] = apic_id[i] & hwthread_mask;
 550         cpuid->core_id[i]     = (apic_id[i] >> hwthread_bits) & core_mask_after_shift;
 551         cpuid->package_id[i]  = apic_id[i] >> (core_bits + hwthread_bits);
 552     }
 553
 554     cpuid->npackages            = cpuid_renumber_elements(cpuid->package_id, cpuid->nproc);
 555     cpuid->ncores_per_package   = cpuid_renumber_elements(cpuid->core_id, cpuid->nproc);
 556     cpuid->nhwthreads_per_core  = cpuid_renumber_elements(cpuid->hwthread_id, cpuid->nproc);
 557
 558     /* now check for consistency */
 559     if ( (cpuid->npackages * cpuid->ncores_per_package *
 560           cpuid->nhwthreads_per_core) != cpuid->nproc)
 561     {
 562         /* the packages/cores-per-package/hwthreads-per-core counts are
 563            inconsistent. */
 564         return -1;
 565     }
 566
 567     /* Create a locality order array, i.e. first all resources in package0, which in turn
 568      * are sorted so we first have all resources in core0, where threads are sorted in order, etc.
 569      */
 570
 571     for (i = 0; i < cpuid->nproc; i++)
 572     {
 573         idx = (cpuid->package_id[i]*cpuid->ncores_per_package + cpuid->core_id[i])*cpuid->nhwthreads_per_core + cpuid->hwthread_id[i];
 574         cpuid->locality_order[idx] = i;
 575     }
 576     return 0;
 577 }
 578
 579
 580 /* Detection of AMD-specific CPU features */
 581 static int
 582 cpuid_check_amd_x86(gmx_cpuid_t                cpuid)
 583 {
 584     int                       max_stdfn, max_extfn, ret;
 585     unsigned int              eax, ebx, ecx, edx;
 586     int                       hwthread_bits, core_bits;
 587     int *                     apic_id;
 588
 589     cpuid_check_common_x86(cpuid);
 590
 591     execute_x86cpuid(0x0, 0, &eax, &ebx, &ecx, &edx);
 592     max_stdfn = eax;
 593
 594     execute_x86cpuid(0x80000000, 0, &eax, &ebx, &ecx, &edx);
 595     max_extfn = eax;
 596
 597     if (max_extfn >= 0x80000001)
 598     {
 599         execute_x86cpuid(0x80000001, 0, &eax, &ebx, &ecx, &edx);
 600
 601         cpuid->feature[GMX_CPUID_FEATURE_X86_SSE4A]       = (ecx & (1 << 6))  != 0;
 602         cpuid->feature[GMX_CPUID_FEATURE_X86_MISALIGNSSE] = (ecx & (1 << 7))  != 0;
 603         cpuid->feature[GMX_CPUID_FEATURE_X86_XOP]         = (ecx & (1 << 11)) != 0;
 604         cpuid->feature[GMX_CPUID_FEATURE_X86_FMA4]        = (ecx & (1 << 16)) != 0;
 605     }
 606
 607     /* Query APIC information on AMD */
 608     if (max_extfn >= 0x80000008)
 609     {
 610 #if (defined HAVE_SCHED_AFFINITY && defined HAVE_SYSCONF && defined __linux__)
 611         /* Linux */
 612         unsigned int   i;
 613         cpu_set_t      cpuset, save_cpuset;
 614         cpuid->nproc = sysconf(_SC_NPROCESSORS_ONLN);
 615         apic_id      = malloc(sizeof(int)*cpuid->nproc);
 616         sched_getaffinity(0, sizeof(cpu_set_t), &save_cpuset);
 617         /* Get APIC id from each core */
 618         CPU_ZERO(&cpuset);
 619         for (i = 0; i < cpuid->nproc; i++)
 620         {
 621             CPU_SET(i, &cpuset);
 622             sched_setaffinity(0, sizeof(cpu_set_t), &cpuset);
 623             execute_x86cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
 624             apic_id[i] = ebx >> 24;
 625             CPU_CLR(i, &cpuset);
 626         }
 627         /* Reset affinity to the value it had when calling this routine */
 628         sched_setaffinity(0, sizeof(cpu_set_t), &save_cpuset);
 629 #define CPUID_HAVE_APIC
 630 #elif defined GMX_NATIVE_WINDOWS
 631         /* Windows */
 632         DWORD_PTR     i;
 633         SYSTEM_INFO   sysinfo;
 634         unsigned int  save_affinity, affinity;
 635         GetSystemInfo( &sysinfo );
 636         cpuid->nproc  = sysinfo.dwNumberOfProcessors;
 637         apic_id       = malloc(sizeof(int)*cpuid->nproc);
 638         /* Get previous affinity mask */
 639         save_affinity = SetThreadAffinityMask(GetCurrentThread(), 1);
 640         for (i = 0; i < cpuid->nproc; i++)
 641         {
 642             SetThreadAffinityMask(GetCurrentThread(), (((DWORD_PTR)1)<<i));
 643             Sleep(0);
 644             execute_x86cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
 645             apic_id[i] = ebx >> 24;
 646         }
 647         SetThreadAffinityMask(GetCurrentThread(), save_affinity);
 648 #define CPUID_HAVE_APIC
 649 #endif
 650 #ifdef CPUID_HAVE_APIC
 651         /* AMD does not support SMT yet - there are no hwthread bits in apic ID */
 652         hwthread_bits = 0;
 653         /* Get number of core bits in apic ID - try modern extended method first */
 654         execute_x86cpuid(0x80000008, 0, &eax, &ebx, &ecx, &edx);
 655         core_bits = (ecx >> 12) & 0xf;
 656         if (core_bits == 0)
 657         {
 658             /* Legacy method for old single/dual core AMD CPUs */
 659             int i = ecx & 0xF;
 660             for (core_bits = 0; (i>>core_bits) > 0; core_bits++)
 661             {
 662                 ;
 663             }
 664         }
 665         ret = cpuid_x86_decode_apic_id(cpuid, apic_id, core_bits,
 666                                        hwthread_bits);
 667         cpuid->have_cpu_topology = (ret == 0);
 668 #endif
 669     }
 670     return 0;
 671 }
 672
 673 /* Detection of Intel-specific CPU features */
 674 static int
 675 cpuid_check_intel_x86(gmx_cpuid_t                cpuid)
 676 {
 677     unsigned int              max_stdfn, max_extfn, ret;
 678     unsigned int              eax, ebx, ecx, edx;
 679     unsigned int              max_logical_cores, max_physical_cores;
 680     int                       hwthread_bits, core_bits;
 681     int *                     apic_id;
 682
 683     cpuid_check_common_x86(cpuid);
 684
 685     execute_x86cpuid(0x0, 0, &eax, &ebx, &ecx, &edx);
 686     max_stdfn = eax;
 687
 688     execute_x86cpuid(0x80000000, 0, &eax, &ebx, &ecx, &edx);
 689     max_extfn = eax;
 690
 691     if (max_stdfn >= 1)
 692     {
 693         execute_x86cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
 694         cpuid->feature[GMX_CPUID_FEATURE_X86_PDCM]    = (ecx & (1 << 15)) != 0;
 695         cpuid->feature[GMX_CPUID_FEATURE_X86_PCID]    = (ecx & (1 << 17)) != 0;
 696         cpuid->feature[GMX_CPUID_FEATURE_X86_X2APIC]  = (ecx & (1 << 21)) != 0;
 697         cpuid->feature[GMX_CPUID_FEATURE_X86_TDT]     = (ecx & (1 << 24)) != 0;
 698     }
 699
 700     if (max_stdfn >= 7)
 701     {
 702         execute_x86cpuid(0x7, 0, &eax, &ebx, &ecx, &edx);
 703         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX2]      = (ebx & (1 << 5))  != 0;
 704         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX_512F]  = (ebx & (1 << 16)) != 0;
 705         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX_512PF] = (ebx & (1 << 26)) != 0;
 706         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX_512ER] = (ebx & (1 << 27)) != 0;
 707         cpuid->feature[GMX_CPUID_FEATURE_X86_AVX_512CD] = (ebx & (1 << 28)) != 0;
 708     }
 709
 710     /* Check whether Hyper-Threading is enabled, not only supported */
 711     if (cpuid->feature[GMX_CPUID_FEATURE_X86_HTT] && max_stdfn >= 4)
 712     {
 713         execute_x86cpuid(0x1, 0, &eax, &ebx, &ecx, &edx);
 714         max_logical_cores  = (ebx >> 16) & 0x0FF;
 715         execute_x86cpuid(0x4, 0, &eax, &ebx, &ecx, &edx);
 716         max_physical_cores = ((eax >> 26) & 0x3F) + 1;
 717
 718         /* Clear HTT flag if we only have 1 logical core per physical */
 719         if (max_logical_cores/max_physical_cores < 2)
 720         {
 721             cpuid->feature[GMX_CPUID_FEATURE_X86_HTT] = 0;
 722         }
 723     }
 724
 725     if (max_stdfn >= 0xB)
 726     {
 727         /* Query x2 APIC information from cores */
 728 #if (defined HAVE_SCHED_AFFINITY && defined HAVE_SYSCONF && defined __linux__)
 729         /* Linux */
 730         unsigned int   i;
 731         cpu_set_t      cpuset, save_cpuset;
 732         cpuid->nproc = sysconf(_SC_NPROCESSORS_ONLN);
 733         apic_id      = malloc(sizeof(int)*cpuid->nproc);
 734         sched_getaffinity(0, sizeof(cpu_set_t), &save_cpuset);
 735         /* Get x2APIC ID from each hardware thread */
 736         CPU_ZERO(&cpuset);
 737         for (i = 0; i < cpuid->nproc; i++)
 738         {
 739             CPU_SET(i, &cpuset);
 740             sched_setaffinity(0, sizeof(cpu_set_t), &cpuset);
 741             execute_x86cpuid(0xB, 0, &eax, &ebx, &ecx, &edx);
 742             apic_id[i] = edx;
 743             CPU_CLR(i, &cpuset);
 744         }
 745         /* Reset affinity to the value it had when calling this routine */
 746         sched_setaffinity(0, sizeof(cpu_set_t), &save_cpuset);
 747 #define CPUID_HAVE_APIC
 748 #elif defined GMX_NATIVE_WINDOWS
 749         /* Windows */
 750         DWORD_PTR     i;
 751         SYSTEM_INFO   sysinfo;
 752         unsigned int  save_affinity, affinity;
 753         GetSystemInfo( &sysinfo );
 754         cpuid->nproc  = sysinfo.dwNumberOfProcessors;
 755         apic_id       = malloc(sizeof(int)*cpuid->nproc);
 756         /* Get previous affinity mask */
 757         save_affinity = SetThreadAffinityMask(GetCurrentThread(), 1);
 758         for (i = 0; i < cpuid->nproc; i++)
 759         {
 760             SetThreadAffinityMask(GetCurrentThread(), (((DWORD_PTR)1)<<i));
 761             Sleep(0);
 762             execute_x86cpuid(0xB, 0, &eax, &ebx, &ecx, &edx);
 763             apic_id[i] = edx;
 764         }
 765         SetThreadAffinityMask(GetCurrentThread(), save_affinity);
 766 #define CPUID_HAVE_APIC
 767 #endif
 768 #ifdef CPUID_HAVE_APIC
 769         execute_x86cpuid(0xB, 0, &eax, &ebx, &ecx, &edx);
 770         hwthread_bits    = eax & 0x1F;
 771         execute_x86cpuid(0xB, 1, &eax, &ebx, &ecx, &edx);
 772         core_bits        = (eax & 0x1F) - hwthread_bits;
 773         ret              = cpuid_x86_decode_apic_id(cpuid, apic_id, core_bits,
 774                                                     hwthread_bits);
 775         cpuid->have_cpu_topology = (ret == 0);
 776 #endif
 777     }
 778     return 0;
 779 }
 780 #endif /* GMX_CPUID_X86 */
 781
 782
 783
 784 static void
 785 chomp_substring_before_colon(const char *in, char *s, int maxlength)
 786 {
 787     char *p;
 788     strncpy(s, in, maxlength);
 789     p = strchr(s, ':');
 790     if (p != NULL)
 791     {
 792         *p = '\0';
 793         while (isspace(*(--p)) && (p >= s))
 794         {
 795             *p = '\0';
 796         }
 797     }
 798     else
 799     {
 800         *s = '\0';
 801     }
 802 }
 803
 804 static void
 805 chomp_substring_after_colon(const char *in, char *s, int maxlength)
 806 {
 807     char *p;
 808     if ( (p = strchr(in, ':')) != NULL)
 809     {
 810         p++;
 811         while (isspace(*p))
 812         {
 813             p++;
 814         }
 815         strncpy(s, p, maxlength);
 816         p = s+strlen(s);
 817         while (isspace(*(--p)) && (p >= s))
 818         {
 819             *p = '\0';
 820         }
 821     }
 822     else
 823     {
 824         *s = '\0';
 825     }
 826 }
 827
 828 static int
 829 cpuid_check_arm(gmx_cpuid_t                cpuid)
 830 {
 831 #if defined(__linux__) || defined(__linux)
 832     FILE *fp;
 833     char  buffer[GMX_CPUID_STRLEN], buffer2[GMX_CPUID_STRLEN], buffer3[GMX_CPUID_STRLEN];
 834
 835     if ( (fp = fopen("/proc/cpuinfo", "r")) != NULL)
 836     {
 837         while ( (fgets(buffer, sizeof(buffer), fp) != NULL))
 838         {
 839             chomp_substring_before_colon(buffer, buffer2, GMX_CPUID_STRLEN);
 840             chomp_substring_after_colon(buffer, buffer3, GMX_CPUID_STRLEN);
 841
 842             if (!strcmp(buffer2, "Processor"))
 843             {
 844                 strncpy(cpuid->brand, buffer3, GMX_CPUID_STRLEN);
 845             }
 846             else if (!strcmp(buffer2, "CPU architecture"))
 847             {
 848                 cpuid->family = strtol(buffer3, NULL, 10);
 849                 if (!strcmp(buffer3, "AArch64"))
 850                 {
 851                     cpuid->family = 8;
 852                 }
 853             }
 854             else if (!strcmp(buffer2, "CPU part"))
 855             {
 856                 cpuid->model = strtol(buffer3, NULL, 16);
 857             }
 858             else if (!strcmp(buffer2, "CPU revision"))
 859             {
 860                 cpuid->stepping = strtol(buffer3, NULL, 10);
 861             }
 862             else if (!strcmp(buffer2, "Features") && strstr(buffer3, "neon"))
 863             {
 864                 cpuid->feature[GMX_CPUID_FEATURE_ARM_NEON] = 1;
 865             }
 866             else if (!strcmp(buffer2, "Features") && strstr(buffer3, "asimd"))
 867             {
 868                 cpuid->feature[GMX_CPUID_FEATURE_ARM_NEON_ASIMD] = 1;
 869             }
 870         }
 871     }
 872     fclose(fp);
 873 #else
 874 #    ifdef __aarch64__
 875     /* Strange 64-bit non-linux platform. However, since NEON ASIMD is present on all
 876      * implementations of AArch64 this far, we assume it is present for now.
 877      */
 878     cpuid->feature[GMX_CPUID_FEATURE_ARM_NEON_ASIMD] = 1;
 879 #    else
 880     /* Strange 32-bit non-linux platform. We cannot assume that neon is present. */
 881     cpuid->feature[GMX_CPUID_FEATURE_ARM_NEON] = 0;
 882 #    endif
 883 #endif
 884     return 0;
 885 }
 886
 887
 888 static int
 889 cpuid_check_ibm(gmx_cpuid_t                cpuid)
 890 {
 891 #if defined(__linux__) || defined(__linux)
 892     FILE *fp;
 893     char  buffer[GMX_CPUID_STRLEN], before_colon[GMX_CPUID_STRLEN], after_colon[GMX_CPUID_STRLEN];
 894
 895     if ( (fp = fopen("/proc/cpuinfo", "r")) != NULL)
 896     {
 897         while ( (fgets(buffer, sizeof(buffer), fp) != NULL))
 898         {
 899             chomp_substring_before_colon(buffer, before_colon, GMX_CPUID_STRLEN);
 900             chomp_substring_after_colon(buffer, after_colon, GMX_CPUID_STRLEN);
 901
 902             if (!strcmp(before_colon, "cpu") || !strcmp(before_colon, "Processor"))
 903             {
 904                 strncpy(cpuid->brand, after_colon, GMX_CPUID_STRLEN);
 905             }
 906             if (!strcmp(before_colon, "model name") ||
 907                 !strcmp(before_colon, "model") ||
 908                 !strcmp(before_colon, "Processor") ||
 909                 !strcmp(before_colon, "cpu"))
 910             {
 911                 if (strstr(after_colon, "altivec"))
 912                 {
 913                     cpuid->feature[GMX_CPUID_FEATURE_IBM_VMX] = 1;
 914
 915                     if (!strstr(after_colon, "POWER6") && !strstr(after_colon, "Power6") &&
 916                         !strstr(after_colon, "power6"))
 917                     {
 918                         cpuid->feature[GMX_CPUID_FEATURE_IBM_VSX] = 1;
 919                     }
 920                 }
 921             }
 922         }
 923     }
 924     fclose(fp);
 925
 926     if (strstr(cpuid->brand, "A2"))
 927     {
 928         /* BlueGene/Q */
 929         cpuid->feature[GMX_CPUID_FEATURE_IBM_QPX] = 1;
 930     }
 931 #else
 932     strncpy(cpuid->brand, "Unknown CPU brand", GMX_CPUID_STRLEN);
 933     cpuid->feature[GMX_CPUID_FEATURE_IBM_QPX] = 0;
 934     cpuid->feature[GMX_CPUID_FEATURE_IBM_VMX] = 0;
 935     cpuid->feature[GMX_CPUID_FEATURE_IBM_VSX] = 0;
 936 #endif
 937     return 0;
 938 }
 939
 940
 941 /* Try to find the vendor of the current CPU, so we know what specific
 942  * detection routine to call.
 943  */
 944 static enum gmx_cpuid_vendor
 945 cpuid_check_vendor(void)
 946 {
 947     enum gmx_cpuid_vendor      i, vendor;
 948     /* Register data used on x86 */
 949     unsigned int               eax, ebx, ecx, edx;
 950     char                       vendorstring[13];
 951     FILE *                     fp;
 952     char                       buffer[GMX_CPUID_STRLEN];
 953     char                       before_colon[GMX_CPUID_STRLEN];
 954     char                       after_colon[GMX_CPUID_STRLEN];
 955
 956     /* Set default first */
 957     vendor = GMX_CPUID_VENDOR_UNKNOWN;
 958
 959 #ifdef GMX_CPUID_X86
 960     execute_x86cpuid(0x0, 0, &eax, &ebx, &ecx, &edx);
 961
 962     memcpy(vendorstring, &ebx, 4);
 963     memcpy(vendorstring+4, &edx, 4);
 964     memcpy(vendorstring+8, &ecx, 4);
 965
 966     vendorstring[12] = '\0';
 967
 968     for (i = GMX_CPUID_VENDOR_UNKNOWN; i < GMX_CPUID_NVENDORS; i++)
 969     {
 970         if (!strncmp(vendorstring, gmx_cpuid_vendor_string[i], 12))
 971         {
 972             vendor = i;
 973         }
 974     }
 975 #elif defined(__linux__) || defined(__linux)
 976     /* General Linux. Try to get CPU vendor from /proc/cpuinfo */
 977     if ( (fp = fopen("/proc/cpuinfo", "r")) != NULL)
 978     {
 979         while ( (vendor == GMX_CPUID_VENDOR_UNKNOWN) && (fgets(buffer, sizeof(buffer), fp) != NULL))
 980         {
 981             chomp_substring_before_colon(buffer, before_colon, sizeof(before_colon));
 982             /* Intel/AMD use "vendor_id", IBM "vendor", "model", or "cpu". Fujitsu "manufacture".
 983              * On ARM there does not seem to be a vendor, but ARM or AArch64 is listed in the Processor string.
 984              * Add others if you have them!
 985              */
 986             if (!strcmp(before_colon, "vendor_id")
 987                 || !strcmp(before_colon, "vendor")
 988                 || !strcmp(before_colon, "manufacture")
 989                 || !strcmp(before_colon, "model")
 990                 || !strcmp(before_colon, "Processor")
 991                 || !strcmp(before_colon, "cpu"))
 992             {
 993                 chomp_substring_after_colon(buffer, after_colon, sizeof(after_colon));
 994                 for (i = GMX_CPUID_VENDOR_UNKNOWN; i < GMX_CPUID_NVENDORS; i++)
 995                 {
 996                     /* Be liberal and accept if we find the vendor
 997                      * string (or alternative string) anywhere. Using
 998                      * strcasestr() would be non-portable. */
 999                     if (strstr(after_colon, gmx_cpuid_vendor_string[i])
1000                         || strstr(after_colon, gmx_cpuid_vendor_string_alternative[i]))
1001                     {
1002                         vendor = i;
1003                     }
1004                 }
1005                 /* If we did not find vendor yet, check if it is IBM:
1006                  * On some Power/PowerPC systems it only says power, not IBM.
1007                  */
1008                 if (vendor == GMX_CPUID_VENDOR_UNKNOWN &&
1009                     ((strstr(after_colon, "POWER") || strstr(after_colon, "Power") ||
1010                       strstr(after_colon, "power"))))
1011                 {
1012                     vendor = GMX_CPUID_VENDOR_IBM;
1013                 }
1014             }
1015         }
1016     }
1017     fclose(fp);
1018 #elif defined(__arm__) || defined (__arm) || defined(__aarch64__)
1019     /* If we are using ARM on something that is not linux we have to trust the compiler,
1020      * and we cannot get the extra info that might be present in /proc/cpuinfo.
1021      */
1022     vendor = GMX_CPUID_VENDOR_ARM;
1023 #endif
1024     return vendor;
1025 }
1026
1027
1028
1029 int
1030 gmx_cpuid_topology(gmx_cpuid_t        cpuid,
1031                    int *              nprocessors,
1032                    int *              npackages,
1033                    int *              ncores_per_package,
1034                    int *              nhwthreads_per_core,
1035                    const int **       package_id,
1036                    const int **       core_id,
1037                    const int **       hwthread_id,
1038                    const int **       locality_order)
1039 {
1040     int rc;
1041
1042     if (cpuid->have_cpu_topology)
1043     {
1044         *nprocessors          = cpuid->nproc;
1045         *npackages            = cpuid->npackages;
1046         *ncores_per_package   = cpuid->ncores_per_package;
1047         *nhwthreads_per_core  = cpuid->nhwthreads_per_core;
1048         *package_id           = cpuid->package_id;
1049         *core_id              = cpuid->core_id;
1050         *hwthread_id          = cpuid->hwthread_id;
1051         *locality_order       = cpuid->locality_order;
1052         rc                    = 0;
1053     }
1054     else
1055     {
1056         rc = -1;
1057     }
1058     return rc;
1059 }
1060
1061
1062 enum gmx_cpuid_x86_smt
1063 gmx_cpuid_x86_smt(gmx_cpuid_t cpuid)
1064 {
1065     enum gmx_cpuid_x86_smt rc;
1066
1067     if (cpuid->have_cpu_topology)
1068     {
1069         rc = (cpuid->nhwthreads_per_core > 1) ? GMX_CPUID_X86_SMT_ENABLED : GMX_CPUID_X86_SMT_DISABLED;
1070     }
1071     else if (cpuid->vendor == GMX_CPUID_VENDOR_AMD || gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_HTT) == 0)
1072     {
1073         rc = GMX_CPUID_X86_SMT_DISABLED;
1074     }
1075     else
1076     {
1077         rc = GMX_CPUID_X86_SMT_CANNOTDETECT;
1078     }
1079     return rc;
1080 }
1081
1082
1083 int
1084 gmx_cpuid_init               (gmx_cpuid_t *              pcpuid)
1085 {
1086     gmx_cpuid_t cpuid;
1087     int         i;
1088     FILE *      fp;
1089     char        buffer[GMX_CPUID_STRLEN], buffer2[GMX_CPUID_STRLEN];
1090     int         found_brand;
1091
1092     cpuid = malloc(sizeof(*cpuid));
1093
1094     *pcpuid = cpuid;
1095
1096     for (i = 0; i < GMX_CPUID_NFEATURES; i++)
1097     {
1098         cpuid->feature[i] = 0;
1099     }
1100
1101     cpuid->have_cpu_topology   = 0;
1102     cpuid->nproc               = 0;
1103     cpuid->npackages           = 0;
1104     cpuid->ncores_per_package  = 0;
1105     cpuid->nhwthreads_per_core = 0;
1106     cpuid->package_id          = NULL;
1107     cpuid->core_id             = NULL;
1108     cpuid->hwthread_id         = NULL;
1109     cpuid->locality_order      = NULL;
1110
1111     cpuid->vendor = cpuid_check_vendor();
1112
1113     switch (cpuid->vendor)
1114     {
1115 #ifdef GMX_CPUID_X86
1116         case GMX_CPUID_VENDOR_INTEL:
1117             cpuid_check_intel_x86(cpuid);
1118             break;
1119         case GMX_CPUID_VENDOR_AMD:
1120             cpuid_check_amd_x86(cpuid);
1121             break;
1122 #endif
1123         case GMX_CPUID_VENDOR_ARM:
1124             cpuid_check_arm(cpuid);
1125             break;
1126         case GMX_CPUID_VENDOR_IBM:
1127             cpuid_check_ibm(cpuid);
1128             break;
1129         default:
1130             /* Default value */
1131             strncpy(cpuid->brand, "Unknown CPU brand", GMX_CPUID_STRLEN);
1132 #if defined(__linux__) || defined(__linux)
1133             /* General Linux. Try to get CPU type from /proc/cpuinfo */
1134             if ( (fp = fopen("/proc/cpuinfo", "r")) != NULL)
1135             {
1136                 found_brand = 0;
1137                 while ( (found_brand == 0) && (fgets(buffer, sizeof(buffer), fp) != NULL))
1138                 {
1139                     chomp_substring_before_colon(buffer, buffer2, sizeof(buffer2));
1140                     /* Intel uses "model name", Fujitsu and IBM "cpu". */
1141                     if (!strcmp(buffer2, "model name") || !strcmp(buffer2, "cpu"))
1142                     {
1143                         chomp_substring_after_colon(buffer, cpuid->brand, GMX_CPUID_STRLEN);
1144                         found_brand = 1;
1145                     }
1146                 }
1147             }
1148             fclose(fp);
1149 #endif
1150             cpuid->family         = 0;
1151             cpuid->model          = 0;
1152             cpuid->stepping       = 0;
1153
1154             for (i = 0; i < GMX_CPUID_NFEATURES; i++)
1155             {
1156                 cpuid->feature[i] = 0;
1157             }
1158             cpuid->feature[GMX_CPUID_FEATURE_CANNOTDETECT] = 1;
1159             break;
1160     }
1161     return 0;
1162 }
1163
1164
1165
1166 void
1167 gmx_cpuid_done               (gmx_cpuid_t              cpuid)
1168 {
1169     free(cpuid);
1170 }
1171
1172
1173 int
1174 gmx_cpuid_formatstring       (gmx_cpuid_t              cpuid,
1175                               char *                   str,
1176                               int                      n)
1177 {
1178     int                     c;
1179     int                     i;
1180     enum gmx_cpuid_feature  feature;
1181
1182 #ifdef _MSC_VER
1183     _snprintf(str, n,
1184               "    Vendor: %s\n"
1185               "    Brand:  %s\n"
1186               "    Family: %2d  model: %2d  stepping: %2d\n"
1187               "    CPU features:",
1188               gmx_cpuid_vendor_string[gmx_cpuid_vendor(cpuid)],
1189               gmx_cpuid_brand(cpuid),
1190               gmx_cpuid_family(cpuid), gmx_cpuid_model(cpuid), gmx_cpuid_stepping(cpuid));
1191 #else
1192     snprintf(str, n,
1193              "    Vendor: %s\n"
1194              "    Brand:  %s\n"
1195              "    Family: %2d  model: %2d  stepping: %2d\n"
1196              "    CPU features:",
1197              gmx_cpuid_vendor_string[gmx_cpuid_vendor(cpuid)],
1198              gmx_cpuid_brand(cpuid),
1199              gmx_cpuid_family(cpuid), gmx_cpuid_model(cpuid), gmx_cpuid_stepping(cpuid));
1200 #endif
1201
1202     str[n-1] = '\0';
1203     c        = strlen(str);
1204     n       -= c;
1205     str     += c;
1206
1207     for (feature = GMX_CPUID_FEATURE_CANNOTDETECT; feature < GMX_CPUID_NFEATURES; feature++)
1208     {
1209         if (gmx_cpuid_feature(cpuid, feature) == 1)
1210         {
1211 #ifdef _MSC_VER
1212             _snprintf(str, n, " %s", gmx_cpuid_feature_string[feature]);
1213 #else
1214             snprintf(str, n, " %s", gmx_cpuid_feature_string[feature]);
1215 #endif
1216             str[n-1] = '\0';
1217             c        = strlen(str);
1218             n       -= c;
1219             str     += c;
1220         }
1221     }
1222 #ifdef _MSC_VER
1223     _snprintf(str, n, "\n");
1224 #else
1225     snprintf(str, n, "\n");
1226 #endif
1227     str[n-1] = '\0';
1228
1229     return 0;
1230 }
1231
1232
1233
1234 enum gmx_cpuid_simd
1235 gmx_cpuid_simd_suggest  (gmx_cpuid_t                 cpuid)
1236 {
1237     enum gmx_cpuid_simd  tmpsimd;
1238
1239     tmpsimd = GMX_CPUID_SIMD_NONE;
1240
1241     if (gmx_cpuid_vendor(cpuid) == GMX_CPUID_VENDOR_INTEL)
1242     {
1243         /* TODO: Add check for AVX-512F & AVX-512ER here as soon as we
1244          * have implemented verlet kernels for them. Until then,
1245          * we should pick AVX2 instead for the automatic detection.
1246          */
1247         if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_AVX2))
1248         {
1249             tmpsimd = GMX_CPUID_SIMD_X86_AVX2_256;
1250         }
1251         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_AVX))
1252         {
1253             tmpsimd = GMX_CPUID_SIMD_X86_AVX_256;
1254         }
1255         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_SSE4_1))
1256         {
1257             tmpsimd = GMX_CPUID_SIMD_X86_SSE4_1;
1258         }
1259         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_SSE2))
1260         {
1261             tmpsimd = GMX_CPUID_SIMD_X86_SSE2;
1262         }
1263     }
1264     else if (gmx_cpuid_vendor(cpuid) == GMX_CPUID_VENDOR_AMD)
1265     {
1266         if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_AVX2))
1267         {
1268             tmpsimd = GMX_CPUID_SIMD_X86_AVX2_256;
1269         }
1270         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_AVX))
1271         {
1272             if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_FMA))
1273             {
1274                 tmpsimd = GMX_CPUID_SIMD_X86_AVX_128_FMA;
1275             }
1276             else
1277             {
1278                 tmpsimd = GMX_CPUID_SIMD_X86_AVX_256;
1279             }
1280         }
1281         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_SSE4_1))
1282         {
1283             tmpsimd = GMX_CPUID_SIMD_X86_SSE4_1;
1284         }
1285         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_X86_SSE2))
1286         {
1287             tmpsimd = GMX_CPUID_SIMD_X86_SSE2;
1288         }
1289     }
1290     else if (gmx_cpuid_vendor(cpuid) == GMX_CPUID_VENDOR_FUJITSU)
1291     {
1292         if (strstr(gmx_cpuid_brand(cpuid), "SPARC64"))
1293         {
1294             tmpsimd = GMX_CPUID_SIMD_SPARC64_HPC_ACE;
1295         }
1296     }
1297     else if (gmx_cpuid_vendor(cpuid) == GMX_CPUID_VENDOR_IBM)
1298     {
1299         if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_IBM_QPX))
1300         {
1301             tmpsimd = GMX_CPUID_SIMD_IBM_QPX;
1302         }
1303         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_IBM_VSX))
1304         {
1305             /* VSX is better than VMX, so we check it first */
1306             tmpsimd = GMX_CPUID_SIMD_IBM_VSX;
1307         }
1308         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_IBM_VMX))
1309         {
1310             tmpsimd = GMX_CPUID_SIMD_IBM_VMX;
1311         }
1312     }
1313     else if (gmx_cpuid_vendor(cpuid) == GMX_CPUID_VENDOR_ARM)
1314     {
1315         if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_ARM_NEON_ASIMD))
1316         {
1317             tmpsimd = GMX_CPUID_SIMD_ARM_NEON_ASIMD;
1318         }
1319         else if (gmx_cpuid_feature(cpuid, GMX_CPUID_FEATURE_ARM_NEON))
1320         {
1321             tmpsimd = GMX_CPUID_SIMD_ARM_NEON;
1322         }
1323     }
1324     return tmpsimd;
1325 }
1326
1327
1328 int
1329 gmx_cpuid_simd_check(enum gmx_cpuid_simd  simd_suggest,
1330                      FILE *               log,
1331                      int                  print_to_stderr)
1332 {
1333     int  rc;
1334
1335     rc = (simd_suggest != compiled_simd);
1336
1337     if (rc != 0)
1338     {
1339         if (log != NULL)
1340         {
1341             fprintf(log, "\nBinary not matching hardware - you might be losing performance.\n"
1342                     "SIMD instructions most likely to fit this hardware: %s\n"
1343                     "SIMD instructions selected at GROMACS compile time: %s\n\n",
1344                     gmx_cpuid_simd_string[simd_suggest],
1345                     gmx_cpuid_simd_string[compiled_simd]);
1346         }
1347         if (print_to_stderr)
1348         {
1349             fprintf(stderr, "Compiled SIMD instructions: %s, GROMACS could use %s on this machine, which is better\n\n",
1350                     gmx_cpuid_simd_string[compiled_simd],
1351                     gmx_cpuid_simd_string[simd_suggest]);
1352         }
1353     }
1354     return rc;
1355 }
1356
1357
1358 #ifdef GMX_CPUID_STANDALONE
1359 /* Stand-alone program to enable queries of CPU features from Cmake.
1360  * Note that you need to check inline ASM capabilities before compiling and set
1361  * -DGMX_X86_GCC_INLINE_ASM for the cpuid instruction to work...
1362  */
1363 int
1364 main(int argc, char **argv)
1365 {
1366     gmx_cpuid_t                   cpuid;
1367     enum gmx_cpuid_simd           simd;
1368     int                           i, cnt;
1369
1370     if (argc < 2)
1371     {
1372         fprintf(stdout,
1373                 "Usage:\n\n%s [flags]\n\n"
1374                 "Available flags:\n"
1375                 "-vendor        Print CPU vendor.\n"
1376                 "-brand         Print CPU brand string.\n"
1377                 "-family        Print CPU family version.\n"
1378                 "-model         Print CPU model version.\n"
1379                 "-stepping      Print CPU stepping version.\n"
1380                 "-features      Print CPU feature flags.\n"
1381                 "-simd          Print suggested GROMACS SIMD instructions.\n",
1382                 argv[0]);
1383         exit(0);
1384     }
1385
1386     gmx_cpuid_init(&cpuid);
1387
1388     if (!strncmp(argv[1], "-vendor", 3))
1389     {
1390         printf("%s\n", gmx_cpuid_vendor_string[cpuid->vendor]);
1391     }
1392     else if (!strncmp(argv[1], "-brand", 3))
1393     {
1394         printf("%s\n", cpuid->brand);
1395     }
1396     else if (!strncmp(argv[1], "-family", 3))
1397     {
1398         printf("%d\n", cpuid->family);
1399     }
1400     else if (!strncmp(argv[1], "-model", 3))
1401     {
1402         printf("%d\n", cpuid->model);
1403     }
1404     else if (!strncmp(argv[1], "-stepping", 3))
1405     {
1406         printf("%d\n", cpuid->stepping);
1407     }
1408     else if (!strncmp(argv[1], "-features", 3))
1409     {
1410         cnt = 0;
1411         for (i = 0; i < GMX_CPUID_NFEATURES; i++)
1412         {
1413             if (cpuid->feature[i] == 1)
1414             {
1415                 if (cnt++ > 0)
1416                 {
1417                     printf(" ");
1418                 }
1419                 printf("%s", gmx_cpuid_feature_string[i]);
1420             }
1421         }
1422         printf("\n");
1423     }
1424     else if (!strncmp(argv[1], "-simd", 3))
1425     {
1426         simd = gmx_cpuid_simd_suggest(cpuid);
1427         fprintf(stdout, "%s\n", gmx_cpuid_simd_string[simd]);
1428     }
1429
1430     gmx_cpuid_done(cpuid);
1431
1432
1433     return 0;
1434 }
1435
1436 #endif
1437
1438 /*! \endcond */