1//===-- cpu_model.c - Support for __cpu_model builtin  ------------*- C -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9//  This file is based on LLVM's lib/Support/Host.cpp.
10//  It implements the operating system Host concept and builtin
11//  __cpu_model for the compiler_rt library, for x86 only.
12//
13//===----------------------------------------------------------------------===//
14
15#if (defined(__i386__) || defined(_M_IX86) || defined(__x86_64__) ||           \
16     defined(_M_X64)) &&                                                       \
17    (defined(__GNUC__) || defined(__clang__) || defined(_MSC_VER))
18
19#include <assert.h>
20
21#define bool int
22#define true 1
23#define false 0
24
25#ifdef _MSC_VER
26#include <intrin.h>
27#endif
28
29#ifndef __has_attribute
30#define __has_attribute(attr) 0
31#endif
32
33enum VendorSignatures {
34  SIG_INTEL = 0x756e6547, // Genu
35  SIG_AMD = 0x68747541,   // Auth
36};
37
38enum ProcessorVendors {
39  VENDOR_INTEL = 1,
40  VENDOR_AMD,
41  VENDOR_OTHER,
42  VENDOR_MAX
43};
44
45enum ProcessorTypes {
46  INTEL_BONNELL = 1,
47  INTEL_CORE2,
48  INTEL_COREI7,
49  AMDFAM10H,
50  AMDFAM15H,
51  INTEL_SILVERMONT,
52  INTEL_KNL,
53  AMD_BTVER1,
54  AMD_BTVER2,
55  AMDFAM17H,
56  INTEL_KNM,
57  INTEL_GOLDMONT,
58  INTEL_GOLDMONT_PLUS,
59  INTEL_TREMONT,
60  CPU_TYPE_MAX
61};
62
63enum ProcessorSubtypes {
64  INTEL_COREI7_NEHALEM = 1,
65  INTEL_COREI7_WESTMERE,
66  INTEL_COREI7_SANDYBRIDGE,
67  AMDFAM10H_BARCELONA,
68  AMDFAM10H_SHANGHAI,
69  AMDFAM10H_ISTANBUL,
70  AMDFAM15H_BDVER1,
71  AMDFAM15H_BDVER2,
72  AMDFAM15H_BDVER3,
73  AMDFAM15H_BDVER4,
74  AMDFAM17H_ZNVER1,
75  INTEL_COREI7_IVYBRIDGE,
76  INTEL_COREI7_HASWELL,
77  INTEL_COREI7_BROADWELL,
78  INTEL_COREI7_SKYLAKE,
79  INTEL_COREI7_SKYLAKE_AVX512,
80  INTEL_COREI7_CANNONLAKE,
81  INTEL_COREI7_ICELAKE_CLIENT,
82  INTEL_COREI7_ICELAKE_SERVER,
83  AMDFAM17H_ZNVER2,
84  INTEL_COREI7_CASCADELAKE,
85  CPU_SUBTYPE_MAX
86};
87
88enum ProcessorFeatures {
89  FEATURE_CMOV = 0,
90  FEATURE_MMX,
91  FEATURE_POPCNT,
92  FEATURE_SSE,
93  FEATURE_SSE2,
94  FEATURE_SSE3,
95  FEATURE_SSSE3,
96  FEATURE_SSE4_1,
97  FEATURE_SSE4_2,
98  FEATURE_AVX,
99  FEATURE_AVX2,
100  FEATURE_SSE4_A,
101  FEATURE_FMA4,
102  FEATURE_XOP,
103  FEATURE_FMA,
104  FEATURE_AVX512F,
105  FEATURE_BMI,
106  FEATURE_BMI2,
107  FEATURE_AES,
108  FEATURE_PCLMUL,
109  FEATURE_AVX512VL,
110  FEATURE_AVX512BW,
111  FEATURE_AVX512DQ,
112  FEATURE_AVX512CD,
113  FEATURE_AVX512ER,
114  FEATURE_AVX512PF,
115  FEATURE_AVX512VBMI,
116  FEATURE_AVX512IFMA,
117  FEATURE_AVX5124VNNIW,
118  FEATURE_AVX5124FMAPS,
119  FEATURE_AVX512VPOPCNTDQ,
120  FEATURE_AVX512VBMI2,
121  FEATURE_GFNI,
122  FEATURE_VPCLMULQDQ,
123  FEATURE_AVX512VNNI,
124  FEATURE_AVX512BITALG
125};
126
127// The check below for i386 was copied from clang's cpuid.h (__get_cpuid_max).
128// Check motivated by bug reports for OpenSSL crashing on CPUs without CPUID
129// support. Consequently, for i386, the presence of CPUID is checked first
130// via the corresponding eflags bit.
131static bool isCpuIdSupported() {
132#if defined(__GNUC__) || defined(__clang__)
133#if defined(__i386__)
134  int __cpuid_supported;
135  __asm__("  pushfl\n"
136          "  popl   %%eax\n"
137          "  movl   %%eax,%%ecx\n"
138          "  xorl   $0x00200000,%%eax\n"
139          "  pushl  %%eax\n"
140          "  popfl\n"
141          "  pushfl\n"
142          "  popl   %%eax\n"
143          "  movl   $0,%0\n"
144          "  cmpl   %%eax,%%ecx\n"
145          "  je     1f\n"
146          "  movl   $1,%0\n"
147          "1:"
148          : "=r"(__cpuid_supported)
149          :
150          : "eax", "ecx");
151  if (!__cpuid_supported)
152    return false;
153#endif
154  return true;
155#endif
156  return true;
157}
158
159// This code is copied from lib/Support/Host.cpp.
160// Changes to either file should be mirrored in the other.
161
162/// getX86CpuIDAndInfo - Execute the specified cpuid and return the 4 values in
163/// the specified arguments.  If we can't run cpuid on the host, return true.
164static bool getX86CpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
165                               unsigned *rECX, unsigned *rEDX) {
166#if defined(__GNUC__) || defined(__clang__)
167#if defined(__x86_64__)
168  // gcc doesn't know cpuid would clobber ebx/rbx. Preserve it manually.
169  // FIXME: should we save this for Clang?
170  __asm__("movq\t%%rbx, %%rsi\n\t"
171          "cpuid\n\t"
172          "xchgq\t%%rbx, %%rsi\n\t"
173          : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
174          : "a"(value));
175  return false;
176#elif defined(__i386__)
177  __asm__("movl\t%%ebx, %%esi\n\t"
178          "cpuid\n\t"
179          "xchgl\t%%ebx, %%esi\n\t"
180          : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
181          : "a"(value));
182  return false;
183#else
184  return true;
185#endif
186#elif defined(_MSC_VER)
187  // The MSVC intrinsic is portable across x86 and x64.
188  int registers[4];
189  __cpuid(registers, value);
190  *rEAX = registers[0];
191  *rEBX = registers[1];
192  *rECX = registers[2];
193  *rEDX = registers[3];
194  return false;
195#else
196  return true;
197#endif
198}
199
200/// getX86CpuIDAndInfoEx - Execute the specified cpuid with subleaf and return
201/// the 4 values in the specified arguments.  If we can't run cpuid on the host,
202/// return true.
203static bool getX86CpuIDAndInfoEx(unsigned value, unsigned subleaf,
204                                 unsigned *rEAX, unsigned *rEBX, unsigned *rECX,
205                                 unsigned *rEDX) {
206#if defined(__GNUC__) || defined(__clang__)
207#if defined(__x86_64__)
208  // gcc doesn't know cpuid would clobber ebx/rbx. Preserve it manually.
209  // FIXME: should we save this for Clang?
210  __asm__("movq\t%%rbx, %%rsi\n\t"
211          "cpuid\n\t"
212          "xchgq\t%%rbx, %%rsi\n\t"
213          : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
214          : "a"(value), "c"(subleaf));
215  return false;
216#elif defined(__i386__)
217  __asm__("movl\t%%ebx, %%esi\n\t"
218          "cpuid\n\t"
219          "xchgl\t%%ebx, %%esi\n\t"
220          : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
221          : "a"(value), "c"(subleaf));
222  return false;
223#else
224  return true;
225#endif
226#elif defined(_MSC_VER)
227  int registers[4];
228  __cpuidex(registers, value, subleaf);
229  *rEAX = registers[0];
230  *rEBX = registers[1];
231  *rECX = registers[2];
232  *rEDX = registers[3];
233  return false;
234#else
235  return true;
236#endif
237}
238
239// Read control register 0 (XCR0). Used to detect features such as AVX.
240static bool getX86XCR0(unsigned *rEAX, unsigned *rEDX) {
241#if defined(__GNUC__) || defined(__clang__)
242  // Check xgetbv; this uses a .byte sequence instead of the instruction
243  // directly because older assemblers do not include support for xgetbv and
244  // there is no easy way to conditionally compile based on the assembler used.
245  __asm__(".byte 0x0f, 0x01, 0xd0" : "=a"(*rEAX), "=d"(*rEDX) : "c"(0));
246  return false;
247#elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
248  unsigned long long Result = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
249  *rEAX = Result;
250  *rEDX = Result >> 32;
251  return false;
252#else
253  return true;
254#endif
255}
256
257static void detectX86FamilyModel(unsigned EAX, unsigned *Family,
258                                 unsigned *Model) {
259  *Family = (EAX >> 8) & 0xf; // Bits 8 - 11
260  *Model = (EAX >> 4) & 0xf;  // Bits 4 - 7
261  if (*Family == 6 || *Family == 0xf) {
262    if (*Family == 0xf)
263      // Examine extended family ID if family ID is F.
264      *Family += (EAX >> 20) & 0xff; // Bits 20 - 27
265    // Examine extended model ID if family ID is 6 or F.
266    *Model += ((EAX >> 16) & 0xf) << 4; // Bits 16 - 19
267  }
268}
269
270static void getIntelProcessorTypeAndSubtype(unsigned Family, unsigned Model,
271                                            unsigned Brand_id,
272                                            unsigned Features,
273                                            unsigned Features2, unsigned *Type,
274                                            unsigned *Subtype) {
275  if (Brand_id != 0)
276    return;
277  switch (Family) {
278  case 6:
279    switch (Model) {
280    case 0x0f: // Intel Core 2 Duo processor, Intel Core 2 Duo mobile
281               // processor, Intel Core 2 Quad processor, Intel Core 2 Quad
282               // mobile processor, Intel Core 2 Extreme processor, Intel
283               // Pentium Dual-Core processor, Intel Xeon processor, model
284               // 0Fh. All processors are manufactured using the 65 nm process.
285    case 0x16: // Intel Celeron processor model 16h. All processors are
286               // manufactured using the 65 nm process
287    case 0x17: // Intel Core 2 Extreme processor, Intel Xeon processor, model
288               // 17h. All processors are manufactured using the 45 nm process.
289               //
290               // 45nm: Penryn , Wolfdale, Yorkfield (XE)
291    case 0x1d: // Intel Xeon processor MP. All processors are manufactured using
292               // the 45 nm process.
293      *Type = INTEL_CORE2; // "penryn"
294      break;
295    case 0x1a: // Intel Core i7 processor and Intel Xeon processor. All
296               // processors are manufactured using the 45 nm process.
297    case 0x1e: // Intel(R) Core(TM) i7 CPU         870  @ 2.93GHz.
298               // As found in a Summer 2010 model iMac.
299    case 0x1f:
300    case 0x2e:              // Nehalem EX
301      *Type = INTEL_COREI7; // "nehalem"
302      *Subtype = INTEL_COREI7_NEHALEM;
303      break;
304    case 0x25: // Intel Core i7, laptop version.
305    case 0x2c: // Intel Core i7 processor and Intel Xeon processor. All
306               // processors are manufactured using the 32 nm process.
307    case 0x2f: // Westmere EX
308      *Type = INTEL_COREI7; // "westmere"
309      *Subtype = INTEL_COREI7_WESTMERE;
310      break;
311    case 0x2a: // Intel Core i7 processor. All processors are manufactured
312               // using the 32 nm process.
313    case 0x2d:
314      *Type = INTEL_COREI7; //"sandybridge"
315      *Subtype = INTEL_COREI7_SANDYBRIDGE;
316      break;
317    case 0x3a:
318    case 0x3e:              // Ivy Bridge EP
319      *Type = INTEL_COREI7; // "ivybridge"
320      *Subtype = INTEL_COREI7_IVYBRIDGE;
321      break;
322
323    // Haswell:
324    case 0x3c:
325    case 0x3f:
326    case 0x45:
327    case 0x46:
328      *Type = INTEL_COREI7; // "haswell"
329      *Subtype = INTEL_COREI7_HASWELL;
330      break;
331
332    // Broadwell:
333    case 0x3d:
334    case 0x47:
335    case 0x4f:
336    case 0x56:
337      *Type = INTEL_COREI7; // "broadwell"
338      *Subtype = INTEL_COREI7_BROADWELL;
339      break;
340
341    // Skylake:
342    case 0x4e:              // Skylake mobile
343    case 0x5e:              // Skylake desktop
344    case 0x8e:              // Kaby Lake mobile
345    case 0x9e:              // Kaby Lake desktop
346      *Type = INTEL_COREI7; // "skylake"
347      *Subtype = INTEL_COREI7_SKYLAKE;
348      break;
349
350    // Skylake Xeon:
351    case 0x55:
352      *Type = INTEL_COREI7;
353      if (Features2 & (1 << (FEATURE_AVX512VNNI - 32)))
354        *Subtype = INTEL_COREI7_CASCADELAKE; // "cascadelake"
355      else
356        *Subtype = INTEL_COREI7_SKYLAKE_AVX512; // "skylake-avx512"
357      break;
358
359    // Cannonlake:
360    case 0x66:
361      *Type = INTEL_COREI7;
362      *Subtype = INTEL_COREI7_CANNONLAKE; // "cannonlake"
363      break;
364
365    // Icelake:
366    case 0x7d:
367    case 0x7e:
368      *Type = INTEL_COREI7;
369      *Subtype = INTEL_COREI7_ICELAKE_CLIENT; // "icelake-client"
370      break;
371
372    // Icelake Xeon:
373    case 0x6a:
374    case 0x6c:
375      *Type = INTEL_COREI7;
376      *Subtype = INTEL_COREI7_ICELAKE_SERVER; // "icelake-server"
377      break;
378
379    case 0x1c: // Most 45 nm Intel Atom processors
380    case 0x26: // 45 nm Atom Lincroft
381    case 0x27: // 32 nm Atom Medfield
382    case 0x35: // 32 nm Atom Midview
383    case 0x36: // 32 nm Atom Midview
384      *Type = INTEL_BONNELL;
385      break; // "bonnell"
386
387    // Atom Silvermont codes from the Intel software optimization guide.
388    case 0x37:
389    case 0x4a:
390    case 0x4d:
391    case 0x5a:
392    case 0x5d:
393    case 0x4c: // really airmont
394      *Type = INTEL_SILVERMONT;
395      break; // "silvermont"
396    // Goldmont:
397    case 0x5c: // Apollo Lake
398    case 0x5f: // Denverton
399      *Type = INTEL_GOLDMONT;
400      break; // "goldmont"
401    case 0x7a:
402      *Type = INTEL_GOLDMONT_PLUS;
403      break;
404    case 0x86:
405      *Type = INTEL_TREMONT;
406      break;
407
408    case 0x57:
409      *Type = INTEL_KNL; // knl
410      break;
411
412    case 0x85:
413      *Type = INTEL_KNM; // knm
414      break;
415
416    default: // Unknown family 6 CPU.
417      break;
418      break;
419    }
420  default:
421    break; // Unknown.
422  }
423}
424
425static void getAMDProcessorTypeAndSubtype(unsigned Family, unsigned Model,
426                                          unsigned Features, unsigned Features2,
427                                          unsigned *Type, unsigned *Subtype) {
428  // FIXME: this poorly matches the generated SubtargetFeatureKV table.  There
429  // appears to be no way to generate the wide variety of AMD-specific targets
430  // from the information returned from CPUID.
431  switch (Family) {
432  case 16:
433    *Type = AMDFAM10H; // "amdfam10"
434    switch (Model) {
435    case 2:
436      *Subtype = AMDFAM10H_BARCELONA;
437      break;
438    case 4:
439      *Subtype = AMDFAM10H_SHANGHAI;
440      break;
441    case 8:
442      *Subtype = AMDFAM10H_ISTANBUL;
443      break;
444    }
445    break;
446  case 20:
447    *Type = AMD_BTVER1;
448    break; // "btver1";
449  case 21:
450    *Type = AMDFAM15H;
451    if (Model >= 0x60 && Model <= 0x7f) {
452      *Subtype = AMDFAM15H_BDVER4;
453      break; // "bdver4"; 60h-7Fh: Excavator
454    }
455    if (Model >= 0x30 && Model <= 0x3f) {
456      *Subtype = AMDFAM15H_BDVER3;
457      break; // "bdver3"; 30h-3Fh: Steamroller
458    }
459    if ((Model >= 0x10 && Model <= 0x1f) || Model == 0x02) {
460      *Subtype = AMDFAM15H_BDVER2;
461      break; // "bdver2"; 02h, 10h-1Fh: Piledriver
462    }
463    if (Model <= 0x0f) {
464      *Subtype = AMDFAM15H_BDVER1;
465      break; // "bdver1"; 00h-0Fh: Bulldozer
466    }
467    break;
468  case 22:
469    *Type = AMD_BTVER2;
470    break; // "btver2"
471  case 23:
472    *Type = AMDFAM17H;
473    if (Model >= 0x30 && Model <= 0x3f) {
474      *Subtype = AMDFAM17H_ZNVER2;
475      break; // "znver2"; 30h-3fh: Zen2
476    }
477    if (Model <= 0x0f) {
478      *Subtype = AMDFAM17H_ZNVER1;
479      break; // "znver1"; 00h-0Fh: Zen1
480    }
481    break;
482  default:
483    break; // "generic"
484  }
485}
486
487static void getAvailableFeatures(unsigned ECX, unsigned EDX, unsigned MaxLeaf,
488                                 unsigned *FeaturesOut,
489                                 unsigned *Features2Out) {
490  unsigned Features = 0;
491  unsigned Features2 = 0;
492  unsigned EAX, EBX;
493
494#define setFeature(F)                                                          \
495  do {                                                                         \
496    if (F < 32)                                                                \
497      Features |= 1U << (F & 0x1f);                                            \
498    else if (F < 64)                                                           \
499      Features2 |= 1U << ((F - 32) & 0x1f);                                    \
500  } while (0)
501
502  if ((EDX >> 15) & 1)
503    setFeature(FEATURE_CMOV);
504  if ((EDX >> 23) & 1)
505    setFeature(FEATURE_MMX);
506  if ((EDX >> 25) & 1)
507    setFeature(FEATURE_SSE);
508  if ((EDX >> 26) & 1)
509    setFeature(FEATURE_SSE2);
510
511  if ((ECX >> 0) & 1)
512    setFeature(FEATURE_SSE3);
513  if ((ECX >> 1) & 1)
514    setFeature(FEATURE_PCLMUL);
515  if ((ECX >> 9) & 1)
516    setFeature(FEATURE_SSSE3);
517  if ((ECX >> 12) & 1)
518    setFeature(FEATURE_FMA);
519  if ((ECX >> 19) & 1)
520    setFeature(FEATURE_SSE4_1);
521  if ((ECX >> 20) & 1)
522    setFeature(FEATURE_SSE4_2);
523  if ((ECX >> 23) & 1)
524    setFeature(FEATURE_POPCNT);
525  if ((ECX >> 25) & 1)
526    setFeature(FEATURE_AES);
527
528  // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
529  // indicates that the AVX registers will be saved and restored on context
530  // switch, then we have full AVX support.
531  const unsigned AVXBits = (1 << 27) | (1 << 28);
532  bool HasAVX = ((ECX & AVXBits) == AVXBits) && !getX86XCR0(&EAX, &EDX) &&
533                ((EAX & 0x6) == 0x6);
534  bool HasAVX512Save = HasAVX && ((EAX & 0xe0) == 0xe0);
535
536  if (HasAVX)
537    setFeature(FEATURE_AVX);
538
539  bool HasLeaf7 =
540      MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
541
542  if (HasLeaf7 && ((EBX >> 3) & 1))
543    setFeature(FEATURE_BMI);
544  if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX)
545    setFeature(FEATURE_AVX2);
546  if (HasLeaf7 && ((EBX >> 8) & 1))
547    setFeature(FEATURE_BMI2);
548  if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save)
549    setFeature(FEATURE_AVX512F);
550  if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save)
551    setFeature(FEATURE_AVX512DQ);
552  if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save)
553    setFeature(FEATURE_AVX512IFMA);
554  if (HasLeaf7 && ((EBX >> 26) & 1) && HasAVX512Save)
555    setFeature(FEATURE_AVX512PF);
556  if (HasLeaf7 && ((EBX >> 27) & 1) && HasAVX512Save)
557    setFeature(FEATURE_AVX512ER);
558  if (HasLeaf7 && ((EBX >> 28) & 1) && HasAVX512Save)
559    setFeature(FEATURE_AVX512CD);
560  if (HasLeaf7 && ((EBX >> 30) & 1) && HasAVX512Save)
561    setFeature(FEATURE_AVX512BW);
562  if (HasLeaf7 && ((EBX >> 31) & 1) && HasAVX512Save)
563    setFeature(FEATURE_AVX512VL);
564
565  if (HasLeaf7 && ((ECX >> 1) & 1) && HasAVX512Save)
566    setFeature(FEATURE_AVX512VBMI);
567  if (HasLeaf7 && ((ECX >> 6) & 1) && HasAVX512Save)
568    setFeature(FEATURE_AVX512VBMI2);
569  if (HasLeaf7 && ((ECX >> 8) & 1))
570    setFeature(FEATURE_GFNI);
571  if (HasLeaf7 && ((ECX >> 10) & 1) && HasAVX)
572    setFeature(FEATURE_VPCLMULQDQ);
573  if (HasLeaf7 && ((ECX >> 11) & 1) && HasAVX512Save)
574    setFeature(FEATURE_AVX512VNNI);
575  if (HasLeaf7 && ((ECX >> 12) & 1) && HasAVX512Save)
576    setFeature(FEATURE_AVX512BITALG);
577  if (HasLeaf7 && ((ECX >> 14) & 1) && HasAVX512Save)
578    setFeature(FEATURE_AVX512VPOPCNTDQ);
579
580  if (HasLeaf7 && ((EDX >> 2) & 1) && HasAVX512Save)
581    setFeature(FEATURE_AVX5124VNNIW);
582  if (HasLeaf7 && ((EDX >> 3) & 1) && HasAVX512Save)
583    setFeature(FEATURE_AVX5124FMAPS);
584
585  unsigned MaxExtLevel;
586  getX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
587
588  bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
589                     !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
590  if (HasExtLeaf1 && ((ECX >> 6) & 1))
591    setFeature(FEATURE_SSE4_A);
592  if (HasExtLeaf1 && ((ECX >> 11) & 1))
593    setFeature(FEATURE_XOP);
594  if (HasExtLeaf1 && ((ECX >> 16) & 1))
595    setFeature(FEATURE_FMA4);
596
597  *FeaturesOut = Features;
598  *Features2Out = Features2;
599#undef setFeature
600}
601
602#if defined(HAVE_INIT_PRIORITY)
603#define CONSTRUCTOR_ATTRIBUTE __attribute__((__constructor__ 101))
604#elif __has_attribute(__constructor__)
605#define CONSTRUCTOR_ATTRIBUTE __attribute__((__constructor__))
606#else
607// FIXME: For MSVC, we should make a function pointer global in .CRT$X?? so that
608// this runs during initialization.
609#define CONSTRUCTOR_ATTRIBUTE
610#endif
611
612#ifndef _WIN32
613__attribute__((visibility("hidden")))
614#endif
615int __cpu_indicator_init(void) CONSTRUCTOR_ATTRIBUTE;
616
617#ifndef _WIN32
618__attribute__((visibility("hidden")))
619#endif
620struct __processor_model {
621  unsigned int __cpu_vendor;
622  unsigned int __cpu_type;
623  unsigned int __cpu_subtype;
624  unsigned int __cpu_features[1];
625} __cpu_model = {0, 0, 0, {0}};
626
627#ifndef _WIN32
628__attribute__((visibility("hidden")))
629#endif
630unsigned int __cpu_features2;
631
632// A constructor function that is sets __cpu_model and __cpu_features2 with
633// the right values.  This needs to run only once.  This constructor is
634// given the highest priority and it should run before constructors without
635// the priority set.  However, it still runs after ifunc initializers and
636// needs to be called explicitly there.
637
638int CONSTRUCTOR_ATTRIBUTE __cpu_indicator_init(void) {
639  unsigned EAX, EBX, ECX, EDX;
640  unsigned MaxLeaf = 5;
641  unsigned Vendor;
642  unsigned Model, Family, Brand_id;
643  unsigned Features = 0;
644  unsigned Features2 = 0;
645
646  // This function needs to run just once.
647  if (__cpu_model.__cpu_vendor)
648    return 0;
649
650  if (!isCpuIdSupported())
651    return -1;
652
653  // Assume cpuid insn present. Run in level 0 to get vendor id.
654  if (getX86CpuIDAndInfo(0, &MaxLeaf, &Vendor, &ECX, &EDX) || MaxLeaf < 1) {
655    __cpu_model.__cpu_vendor = VENDOR_OTHER;
656    return -1;
657  }
658  getX86CpuIDAndInfo(1, &EAX, &EBX, &ECX, &EDX);
659  detectX86FamilyModel(EAX, &Family, &Model);
660  Brand_id = EBX & 0xff;
661
662  // Find available features.
663  getAvailableFeatures(ECX, EDX, MaxLeaf, &Features, &Features2);
664  __cpu_model.__cpu_features[0] = Features;
665  __cpu_features2 = Features2;
666
667  if (Vendor == SIG_INTEL) {
668    // Get CPU type.
669    getIntelProcessorTypeAndSubtype(Family, Model, Brand_id, Features,
670                                    Features2, &(__cpu_model.__cpu_type),
671                                    &(__cpu_model.__cpu_subtype));
672    __cpu_model.__cpu_vendor = VENDOR_INTEL;
673  } else if (Vendor == SIG_AMD) {
674    // Get CPU type.
675    getAMDProcessorTypeAndSubtype(Family, Model, Features, Features2,
676                                  &(__cpu_model.__cpu_type),
677                                  &(__cpu_model.__cpu_subtype));
678    __cpu_model.__cpu_vendor = VENDOR_AMD;
679  } else
680    __cpu_model.__cpu_vendor = VENDOR_OTHER;
681
682  assert(__cpu_model.__cpu_vendor < VENDOR_MAX);
683  assert(__cpu_model.__cpu_type < CPU_TYPE_MAX);
684  assert(__cpu_model.__cpu_subtype < CPU_SUBTYPE_MAX);
685
686  return 0;
687}
688
689#endif
690