1 //===-- Host.cpp - Implement OS Host Concept --------------------*- 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 implements the operating system Host concept.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/Support/Host.h"
14 #include "llvm/ADT/SmallVector.h"
15 #include "llvm/ADT/StringMap.h"
16 #include "llvm/ADT/StringRef.h"
17 #include "llvm/ADT/StringSwitch.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/Config/llvm-config.h"
20 #include "llvm/Support/MemoryBuffer.h"
21 #include "llvm/Support/X86TargetParser.h"
22 #include "llvm/Support/raw_ostream.h"
23 #include <string.h>
24 
25 // Include the platform-specific parts of this class.
26 #ifdef LLVM_ON_UNIX
27 #include "Unix/Host.inc"
28 #include <sched.h>
29 #endif
30 #ifdef _WIN32
31 #include "Windows/Host.inc"
32 #endif
33 #ifdef _MSC_VER
34 #include <intrin.h>
35 #endif
36 #ifdef __MVS__
37 #include "llvm/Support/BCD.h"
38 #endif
39 #if defined(__APPLE__)
40 #include <mach/host_info.h>
41 #include <mach/mach.h>
42 #include <mach/mach_host.h>
43 #include <mach/machine.h>
44 #include <sys/param.h>
45 #include <sys/sysctl.h>
46 #endif
47 #ifdef _AIX
48 #include <sys/systemcfg.h>
49 #endif
50 
51 #define DEBUG_TYPE "host-detection"
52 
53 //===----------------------------------------------------------------------===//
54 //
55 //  Implementations of the CPU detection routines
56 //
57 //===----------------------------------------------------------------------===//
58 
59 using namespace llvm;
60 
61 static std::unique_ptr<llvm::MemoryBuffer>
62     LLVM_ATTRIBUTE_UNUSED getProcCpuinfoContent() {
63   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Text =
64       llvm::MemoryBuffer::getFileAsStream("/proc/cpuinfo");
65   if (std::error_code EC = Text.getError()) {
66     llvm::errs() << "Can't read "
67                  << "/proc/cpuinfo: " << EC.message() << "\n";
68     return nullptr;
69   }
70   return std::move(*Text);
71 }
72 
73 StringRef sys::detail::getHostCPUNameForPowerPC(StringRef ProcCpuinfoContent) {
74   // Access to the Processor Version Register (PVR) on PowerPC is privileged,
75   // and so we must use an operating-system interface to determine the current
76   // processor type. On Linux, this is exposed through the /proc/cpuinfo file.
77   const char *generic = "generic";
78 
79   // The cpu line is second (after the 'processor: 0' line), so if this
80   // buffer is too small then something has changed (or is wrong).
81   StringRef::const_iterator CPUInfoStart = ProcCpuinfoContent.begin();
82   StringRef::const_iterator CPUInfoEnd = ProcCpuinfoContent.end();
83 
84   StringRef::const_iterator CIP = CPUInfoStart;
85 
86   StringRef::const_iterator CPUStart = nullptr;
87   size_t CPULen = 0;
88 
89   // We need to find the first line which starts with cpu, spaces, and a colon.
90   // After the colon, there may be some additional spaces and then the cpu type.
91   while (CIP < CPUInfoEnd && CPUStart == nullptr) {
92     if (CIP < CPUInfoEnd && *CIP == '\n')
93       ++CIP;
94 
95     if (CIP < CPUInfoEnd && *CIP == 'c') {
96       ++CIP;
97       if (CIP < CPUInfoEnd && *CIP == 'p') {
98         ++CIP;
99         if (CIP < CPUInfoEnd && *CIP == 'u') {
100           ++CIP;
101           while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
102             ++CIP;
103 
104           if (CIP < CPUInfoEnd && *CIP == ':') {
105             ++CIP;
106             while (CIP < CPUInfoEnd && (*CIP == ' ' || *CIP == '\t'))
107               ++CIP;
108 
109             if (CIP < CPUInfoEnd) {
110               CPUStart = CIP;
111               while (CIP < CPUInfoEnd && (*CIP != ' ' && *CIP != '\t' &&
112                                           *CIP != ',' && *CIP != '\n'))
113                 ++CIP;
114               CPULen = CIP - CPUStart;
115             }
116           }
117         }
118       }
119     }
120 
121     if (CPUStart == nullptr)
122       while (CIP < CPUInfoEnd && *CIP != '\n')
123         ++CIP;
124   }
125 
126   if (CPUStart == nullptr)
127     return generic;
128 
129   return StringSwitch<const char *>(StringRef(CPUStart, CPULen))
130       .Case("604e", "604e")
131       .Case("604", "604")
132       .Case("7400", "7400")
133       .Case("7410", "7400")
134       .Case("7447", "7400")
135       .Case("7455", "7450")
136       .Case("G4", "g4")
137       .Case("POWER4", "970")
138       .Case("PPC970FX", "970")
139       .Case("PPC970MP", "970")
140       .Case("G5", "g5")
141       .Case("POWER5", "g5")
142       .Case("A2", "a2")
143       .Case("POWER6", "pwr6")
144       .Case("POWER7", "pwr7")
145       .Case("POWER8", "pwr8")
146       .Case("POWER8E", "pwr8")
147       .Case("POWER8NVL", "pwr8")
148       .Case("POWER9", "pwr9")
149       .Case("POWER10", "pwr10")
150       // FIXME: If we get a simulator or machine with the capabilities of
151       // mcpu=future, we should revisit this and add the name reported by the
152       // simulator/machine.
153       .Default(generic);
154 }
155 
156 StringRef sys::detail::getHostCPUNameForARM(StringRef ProcCpuinfoContent) {
157   // The cpuid register on arm is not accessible from user space. On Linux,
158   // it is exposed through the /proc/cpuinfo file.
159 
160   // Read 32 lines from /proc/cpuinfo, which should contain the CPU part line
161   // in all cases.
162   SmallVector<StringRef, 32> Lines;
163   ProcCpuinfoContent.split(Lines, "\n");
164 
165   // Look for the CPU implementer line.
166   StringRef Implementer;
167   StringRef Hardware;
168   StringRef Part;
169   for (unsigned I = 0, E = Lines.size(); I != E; ++I) {
170     if (Lines[I].startswith("CPU implementer"))
171       Implementer = Lines[I].substr(15).ltrim("\t :");
172     if (Lines[I].startswith("Hardware"))
173       Hardware = Lines[I].substr(8).ltrim("\t :");
174     if (Lines[I].startswith("CPU part"))
175       Part = Lines[I].substr(8).ltrim("\t :");
176   }
177 
178   if (Implementer == "0x41") { // ARM Ltd.
179     // MSM8992/8994 may give cpu part for the core that the kernel is running on,
180     // which is undeterministic and wrong. Always return cortex-a53 for these SoC.
181     if (Hardware.endswith("MSM8994") || Hardware.endswith("MSM8996"))
182       return "cortex-a53";
183 
184 
185     // The CPU part is a 3 digit hexadecimal number with a 0x prefix. The
186     // values correspond to the "Part number" in the CP15/c0 register. The
187     // contents are specified in the various processor manuals.
188     // This corresponds to the Main ID Register in Technical Reference Manuals.
189     // and is used in programs like sys-utils
190     return StringSwitch<const char *>(Part)
191         .Case("0x926", "arm926ej-s")
192         .Case("0xb02", "mpcore")
193         .Case("0xb36", "arm1136j-s")
194         .Case("0xb56", "arm1156t2-s")
195         .Case("0xb76", "arm1176jz-s")
196         .Case("0xc08", "cortex-a8")
197         .Case("0xc09", "cortex-a9")
198         .Case("0xc0f", "cortex-a15")
199         .Case("0xc20", "cortex-m0")
200         .Case("0xc23", "cortex-m3")
201         .Case("0xc24", "cortex-m4")
202         .Case("0xd22", "cortex-m55")
203         .Case("0xd02", "cortex-a34")
204         .Case("0xd04", "cortex-a35")
205         .Case("0xd03", "cortex-a53")
206         .Case("0xd07", "cortex-a57")
207         .Case("0xd08", "cortex-a72")
208         .Case("0xd09", "cortex-a73")
209         .Case("0xd0a", "cortex-a75")
210         .Case("0xd0b", "cortex-a76")
211         .Case("0xd0d", "cortex-a77")
212         .Case("0xd41", "cortex-a78")
213         .Case("0xd44", "cortex-x1")
214         .Case("0xd4c", "cortex-x1c")
215         .Case("0xd0c", "neoverse-n1")
216         .Case("0xd49", "neoverse-n2")
217         .Case("0xd40", "neoverse-v1")
218         .Default("generic");
219   }
220 
221   if (Implementer == "0x42" || Implementer == "0x43") { // Broadcom | Cavium.
222     return StringSwitch<const char *>(Part)
223       .Case("0x516", "thunderx2t99")
224       .Case("0x0516", "thunderx2t99")
225       .Case("0xaf", "thunderx2t99")
226       .Case("0x0af", "thunderx2t99")
227       .Case("0xa1", "thunderxt88")
228       .Case("0x0a1", "thunderxt88")
229       .Default("generic");
230   }
231 
232   if (Implementer == "0x46") { // Fujitsu Ltd.
233     return StringSwitch<const char *>(Part)
234       .Case("0x001", "a64fx")
235       .Default("generic");
236   }
237 
238   if (Implementer == "0x4e") { // NVIDIA Corporation
239     return StringSwitch<const char *>(Part)
240         .Case("0x004", "carmel")
241         .Default("generic");
242   }
243 
244   if (Implementer == "0x48") // HiSilicon Technologies, Inc.
245     // The CPU part is a 3 digit hexadecimal number with a 0x prefix. The
246     // values correspond to the "Part number" in the CP15/c0 register. The
247     // contents are specified in the various processor manuals.
248     return StringSwitch<const char *>(Part)
249       .Case("0xd01", "tsv110")
250       .Default("generic");
251 
252   if (Implementer == "0x51") // Qualcomm Technologies, Inc.
253     // The CPU part is a 3 digit hexadecimal number with a 0x prefix. The
254     // values correspond to the "Part number" in the CP15/c0 register. The
255     // contents are specified in the various processor manuals.
256     return StringSwitch<const char *>(Part)
257         .Case("0x06f", "krait") // APQ8064
258         .Case("0x201", "kryo")
259         .Case("0x205", "kryo")
260         .Case("0x211", "kryo")
261         .Case("0x800", "cortex-a73") // Kryo 2xx Gold
262         .Case("0x801", "cortex-a73") // Kryo 2xx Silver
263         .Case("0x802", "cortex-a75") // Kryo 3xx Gold
264         .Case("0x803", "cortex-a75") // Kryo 3xx Silver
265         .Case("0x804", "cortex-a76") // Kryo 4xx Gold
266         .Case("0x805", "cortex-a76") // Kryo 4xx/5xx Silver
267         .Case("0xc00", "falkor")
268         .Case("0xc01", "saphira")
269         .Default("generic");
270   if (Implementer == "0x53") { // Samsung Electronics Co., Ltd.
271     // The Exynos chips have a convoluted ID scheme that doesn't seem to follow
272     // any predictive pattern across variants and parts.
273     unsigned Variant = 0, Part = 0;
274 
275     // Look for the CPU variant line, whose value is a 1 digit hexadecimal
276     // number, corresponding to the Variant bits in the CP15/C0 register.
277     for (auto I : Lines)
278       if (I.consume_front("CPU variant"))
279         I.ltrim("\t :").getAsInteger(0, Variant);
280 
281     // Look for the CPU part line, whose value is a 3 digit hexadecimal
282     // number, corresponding to the PartNum bits in the CP15/C0 register.
283     for (auto I : Lines)
284       if (I.consume_front("CPU part"))
285         I.ltrim("\t :").getAsInteger(0, Part);
286 
287     unsigned Exynos = (Variant << 12) | Part;
288     switch (Exynos) {
289     default:
290       // Default by falling through to Exynos M3.
291       LLVM_FALLTHROUGH;
292     case 0x1002:
293       return "exynos-m3";
294     case 0x1003:
295       return "exynos-m4";
296     }
297   }
298 
299   return "generic";
300 }
301 
302 namespace {
303 StringRef getCPUNameFromS390Model(unsigned int Id, bool HaveVectorSupport) {
304   switch (Id) {
305     case 2064:  // z900 not supported by LLVM
306     case 2066:
307     case 2084:  // z990 not supported by LLVM
308     case 2086:
309     case 2094:  // z9-109 not supported by LLVM
310     case 2096:
311       return "generic";
312     case 2097:
313     case 2098:
314       return "z10";
315     case 2817:
316     case 2818:
317       return "z196";
318     case 2827:
319     case 2828:
320       return "zEC12";
321     case 2964:
322     case 2965:
323       return HaveVectorSupport? "z13" : "zEC12";
324     case 3906:
325     case 3907:
326       return HaveVectorSupport? "z14" : "zEC12";
327     case 8561:
328     case 8562:
329       return HaveVectorSupport? "z15" : "zEC12";
330     case 3931:
331     case 3932:
332     default:
333       return HaveVectorSupport? "arch14" : "zEC12";
334   }
335 }
336 } // end anonymous namespace
337 
338 StringRef sys::detail::getHostCPUNameForS390x(StringRef ProcCpuinfoContent) {
339   // STIDP is a privileged operation, so use /proc/cpuinfo instead.
340 
341   // The "processor 0:" line comes after a fair amount of other information,
342   // including a cache breakdown, but this should be plenty.
343   SmallVector<StringRef, 32> Lines;
344   ProcCpuinfoContent.split(Lines, "\n");
345 
346   // Look for the CPU features.
347   SmallVector<StringRef, 32> CPUFeatures;
348   for (unsigned I = 0, E = Lines.size(); I != E; ++I)
349     if (Lines[I].startswith("features")) {
350       size_t Pos = Lines[I].find(':');
351       if (Pos != StringRef::npos) {
352         Lines[I].drop_front(Pos + 1).split(CPUFeatures, ' ');
353         break;
354       }
355     }
356 
357   // We need to check for the presence of vector support independently of
358   // the machine type, since we may only use the vector register set when
359   // supported by the kernel (and hypervisor).
360   bool HaveVectorSupport = false;
361   for (unsigned I = 0, E = CPUFeatures.size(); I != E; ++I) {
362     if (CPUFeatures[I] == "vx")
363       HaveVectorSupport = true;
364   }
365 
366   // Now check the processor machine type.
367   for (unsigned I = 0, E = Lines.size(); I != E; ++I) {
368     if (Lines[I].startswith("processor ")) {
369       size_t Pos = Lines[I].find("machine = ");
370       if (Pos != StringRef::npos) {
371         Pos += sizeof("machine = ") - 1;
372         unsigned int Id;
373         if (!Lines[I].drop_front(Pos).getAsInteger(10, Id))
374           return getCPUNameFromS390Model(Id, HaveVectorSupport);
375       }
376       break;
377     }
378   }
379 
380   return "generic";
381 }
382 
383 StringRef sys::detail::getHostCPUNameForBPF() {
384 #if !defined(__linux__) || !defined(__x86_64__)
385   return "generic";
386 #else
387   uint8_t v3_insns[40] __attribute__ ((aligned (8))) =
388       /* BPF_MOV64_IMM(BPF_REG_0, 0) */
389     { 0xb7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
390       /* BPF_MOV64_IMM(BPF_REG_2, 1) */
391       0xb7, 0x2, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0,
392       /* BPF_JMP32_REG(BPF_JLT, BPF_REG_0, BPF_REG_2, 1) */
393       0xae, 0x20, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0,
394       /* BPF_MOV64_IMM(BPF_REG_0, 1) */
395       0xb7, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0,
396       /* BPF_EXIT_INSN() */
397       0x95, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
398 
399   uint8_t v2_insns[40] __attribute__ ((aligned (8))) =
400       /* BPF_MOV64_IMM(BPF_REG_0, 0) */
401     { 0xb7, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0,
402       /* BPF_MOV64_IMM(BPF_REG_2, 1) */
403       0xb7, 0x2, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0,
404       /* BPF_JMP_REG(BPF_JLT, BPF_REG_0, BPF_REG_2, 1) */
405       0xad, 0x20, 0x1, 0x0, 0x0, 0x0, 0x0, 0x0,
406       /* BPF_MOV64_IMM(BPF_REG_0, 1) */
407       0xb7, 0x0, 0x0, 0x0, 0x1, 0x0, 0x0, 0x0,
408       /* BPF_EXIT_INSN() */
409       0x95, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0, 0x0 };
410 
411   struct bpf_prog_load_attr {
412     uint32_t prog_type;
413     uint32_t insn_cnt;
414     uint64_t insns;
415     uint64_t license;
416     uint32_t log_level;
417     uint32_t log_size;
418     uint64_t log_buf;
419     uint32_t kern_version;
420     uint32_t prog_flags;
421   } attr = {};
422   attr.prog_type = 1; /* BPF_PROG_TYPE_SOCKET_FILTER */
423   attr.insn_cnt = 5;
424   attr.insns = (uint64_t)v3_insns;
425   attr.license = (uint64_t)"DUMMY";
426 
427   int fd = syscall(321 /* __NR_bpf */, 5 /* BPF_PROG_LOAD */, &attr,
428                    sizeof(attr));
429   if (fd >= 0) {
430     close(fd);
431     return "v3";
432   }
433 
434   /* Clear the whole attr in case its content changed by syscall. */
435   memset(&attr, 0, sizeof(attr));
436   attr.prog_type = 1; /* BPF_PROG_TYPE_SOCKET_FILTER */
437   attr.insn_cnt = 5;
438   attr.insns = (uint64_t)v2_insns;
439   attr.license = (uint64_t)"DUMMY";
440   fd = syscall(321 /* __NR_bpf */, 5 /* BPF_PROG_LOAD */, &attr, sizeof(attr));
441   if (fd >= 0) {
442     close(fd);
443     return "v2";
444   }
445   return "v1";
446 #endif
447 }
448 
449 #if defined(__i386__) || defined(_M_IX86) || \
450     defined(__x86_64__) || defined(_M_X64)
451 
452 // The check below for i386 was copied from clang's cpuid.h (__get_cpuid_max).
453 // Check motivated by bug reports for OpenSSL crashing on CPUs without CPUID
454 // support. Consequently, for i386, the presence of CPUID is checked first
455 // via the corresponding eflags bit.
456 // Removal of cpuid.h header motivated by PR30384
457 // Header cpuid.h and method __get_cpuid_max are not used in llvm, clang, openmp
458 // or test-suite, but are used in external projects e.g. libstdcxx
459 static bool isCpuIdSupported() {
460 #if defined(__GNUC__) || defined(__clang__)
461 #if defined(__i386__)
462   int __cpuid_supported;
463   __asm__("  pushfl\n"
464           "  popl   %%eax\n"
465           "  movl   %%eax,%%ecx\n"
466           "  xorl   $0x00200000,%%eax\n"
467           "  pushl  %%eax\n"
468           "  popfl\n"
469           "  pushfl\n"
470           "  popl   %%eax\n"
471           "  movl   $0,%0\n"
472           "  cmpl   %%eax,%%ecx\n"
473           "  je     1f\n"
474           "  movl   $1,%0\n"
475           "1:"
476           : "=r"(__cpuid_supported)
477           :
478           : "eax", "ecx");
479   if (!__cpuid_supported)
480     return false;
481 #endif
482   return true;
483 #endif
484   return true;
485 }
486 
487 /// getX86CpuIDAndInfo - Execute the specified cpuid and return the 4 values in
488 /// the specified arguments.  If we can't run cpuid on the host, return true.
489 static bool getX86CpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
490                                unsigned *rECX, unsigned *rEDX) {
491 #if defined(__GNUC__) || defined(__clang__)
492 #if defined(__x86_64__)
493   // gcc doesn't know cpuid would clobber ebx/rbx. Preserve it manually.
494   // FIXME: should we save this for Clang?
495   __asm__("movq\t%%rbx, %%rsi\n\t"
496           "cpuid\n\t"
497           "xchgq\t%%rbx, %%rsi\n\t"
498           : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
499           : "a"(value));
500   return false;
501 #elif defined(__i386__)
502   __asm__("movl\t%%ebx, %%esi\n\t"
503           "cpuid\n\t"
504           "xchgl\t%%ebx, %%esi\n\t"
505           : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
506           : "a"(value));
507   return false;
508 #else
509   return true;
510 #endif
511 #elif defined(_MSC_VER)
512   // The MSVC intrinsic is portable across x86 and x64.
513   int registers[4];
514   __cpuid(registers, value);
515   *rEAX = registers[0];
516   *rEBX = registers[1];
517   *rECX = registers[2];
518   *rEDX = registers[3];
519   return false;
520 #else
521   return true;
522 #endif
523 }
524 
525 namespace llvm {
526 namespace sys {
527 namespace detail {
528 namespace x86 {
529 
530 VendorSignatures getVendorSignature(unsigned *MaxLeaf) {
531   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
532   if (MaxLeaf == nullptr)
533     MaxLeaf = &EAX;
534   else
535     *MaxLeaf = 0;
536 
537   if (!isCpuIdSupported())
538     return VendorSignatures::UNKNOWN;
539 
540   if (getX86CpuIDAndInfo(0, MaxLeaf, &EBX, &ECX, &EDX) || *MaxLeaf < 1)
541     return VendorSignatures::UNKNOWN;
542 
543   // "Genu ineI ntel"
544   if (EBX == 0x756e6547 && EDX == 0x49656e69 && ECX == 0x6c65746e)
545     return VendorSignatures::GENUINE_INTEL;
546 
547   // "Auth enti cAMD"
548   if (EBX == 0x68747541 && EDX == 0x69746e65 && ECX == 0x444d4163)
549     return VendorSignatures::AUTHENTIC_AMD;
550 
551   return VendorSignatures::UNKNOWN;
552 }
553 
554 } // namespace x86
555 } // namespace detail
556 } // namespace sys
557 } // namespace llvm
558 
559 using namespace llvm::sys::detail::x86;
560 
561 /// getX86CpuIDAndInfoEx - Execute the specified cpuid with subleaf and return
562 /// the 4 values in the specified arguments.  If we can't run cpuid on the host,
563 /// return true.
564 static bool getX86CpuIDAndInfoEx(unsigned value, unsigned subleaf,
565                                  unsigned *rEAX, unsigned *rEBX, unsigned *rECX,
566                                  unsigned *rEDX) {
567 #if defined(__GNUC__) || defined(__clang__)
568 #if defined(__x86_64__)
569   // gcc doesn't know cpuid would clobber ebx/rbx. Preserve it manually.
570   // FIXME: should we save this for Clang?
571   __asm__("movq\t%%rbx, %%rsi\n\t"
572           "cpuid\n\t"
573           "xchgq\t%%rbx, %%rsi\n\t"
574           : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
575           : "a"(value), "c"(subleaf));
576   return false;
577 #elif defined(__i386__)
578   __asm__("movl\t%%ebx, %%esi\n\t"
579           "cpuid\n\t"
580           "xchgl\t%%ebx, %%esi\n\t"
581           : "=a"(*rEAX), "=S"(*rEBX), "=c"(*rECX), "=d"(*rEDX)
582           : "a"(value), "c"(subleaf));
583   return false;
584 #else
585   return true;
586 #endif
587 #elif defined(_MSC_VER)
588   int registers[4];
589   __cpuidex(registers, value, subleaf);
590   *rEAX = registers[0];
591   *rEBX = registers[1];
592   *rECX = registers[2];
593   *rEDX = registers[3];
594   return false;
595 #else
596   return true;
597 #endif
598 }
599 
600 // Read control register 0 (XCR0). Used to detect features such as AVX.
601 static bool getX86XCR0(unsigned *rEAX, unsigned *rEDX) {
602 #if defined(__GNUC__) || defined(__clang__)
603   // Check xgetbv; this uses a .byte sequence instead of the instruction
604   // directly because older assemblers do not include support for xgetbv and
605   // there is no easy way to conditionally compile based on the assembler used.
606   __asm__(".byte 0x0f, 0x01, 0xd0" : "=a"(*rEAX), "=d"(*rEDX) : "c"(0));
607   return false;
608 #elif defined(_MSC_FULL_VER) && defined(_XCR_XFEATURE_ENABLED_MASK)
609   unsigned long long Result = _xgetbv(_XCR_XFEATURE_ENABLED_MASK);
610   *rEAX = Result;
611   *rEDX = Result >> 32;
612   return false;
613 #else
614   return true;
615 #endif
616 }
617 
618 static void detectX86FamilyModel(unsigned EAX, unsigned *Family,
619                                  unsigned *Model) {
620   *Family = (EAX >> 8) & 0xf; // Bits 8 - 11
621   *Model = (EAX >> 4) & 0xf;  // Bits 4 - 7
622   if (*Family == 6 || *Family == 0xf) {
623     if (*Family == 0xf)
624       // Examine extended family ID if family ID is F.
625       *Family += (EAX >> 20) & 0xff; // Bits 20 - 27
626     // Examine extended model ID if family ID is 6 or F.
627     *Model += ((EAX >> 16) & 0xf) << 4; // Bits 16 - 19
628   }
629 }
630 
631 static StringRef
632 getIntelProcessorTypeAndSubtype(unsigned Family, unsigned Model,
633                                 const unsigned *Features,
634                                 unsigned *Type, unsigned *Subtype) {
635   auto testFeature = [&](unsigned F) {
636     return (Features[F / 32] & (1U << (F % 32))) != 0;
637   };
638 
639   StringRef CPU;
640 
641   switch (Family) {
642   case 3:
643     CPU = "i386";
644     break;
645   case 4:
646     CPU = "i486";
647     break;
648   case 5:
649     if (testFeature(X86::FEATURE_MMX)) {
650       CPU = "pentium-mmx";
651       break;
652     }
653     CPU = "pentium";
654     break;
655   case 6:
656     switch (Model) {
657     case 0x0f: // Intel Core 2 Duo processor, Intel Core 2 Duo mobile
658                // processor, Intel Core 2 Quad processor, Intel Core 2 Quad
659                // mobile processor, Intel Core 2 Extreme processor, Intel
660                // Pentium Dual-Core processor, Intel Xeon processor, model
661                // 0Fh. All processors are manufactured using the 65 nm process.
662     case 0x16: // Intel Celeron processor model 16h. All processors are
663                // manufactured using the 65 nm process
664       CPU = "core2";
665       *Type = X86::INTEL_CORE2;
666       break;
667     case 0x17: // Intel Core 2 Extreme processor, Intel Xeon processor, model
668                // 17h. All processors are manufactured using the 45 nm process.
669                //
670                // 45nm: Penryn , Wolfdale, Yorkfield (XE)
671     case 0x1d: // Intel Xeon processor MP. All processors are manufactured using
672                // the 45 nm process.
673       CPU = "penryn";
674       *Type = X86::INTEL_CORE2;
675       break;
676     case 0x1a: // Intel Core i7 processor and Intel Xeon processor. All
677                // processors are manufactured using the 45 nm process.
678     case 0x1e: // Intel(R) Core(TM) i7 CPU         870  @ 2.93GHz.
679                // As found in a Summer 2010 model iMac.
680     case 0x1f:
681     case 0x2e:              // Nehalem EX
682       CPU = "nehalem";
683       *Type = X86::INTEL_COREI7;
684       *Subtype = X86::INTEL_COREI7_NEHALEM;
685       break;
686     case 0x25: // Intel Core i7, laptop version.
687     case 0x2c: // Intel Core i7 processor and Intel Xeon processor. All
688                // processors are manufactured using the 32 nm process.
689     case 0x2f: // Westmere EX
690       CPU = "westmere";
691       *Type = X86::INTEL_COREI7;
692       *Subtype = X86::INTEL_COREI7_WESTMERE;
693       break;
694     case 0x2a: // Intel Core i7 processor. All processors are manufactured
695                // using the 32 nm process.
696     case 0x2d:
697       CPU = "sandybridge";
698       *Type = X86::INTEL_COREI7;
699       *Subtype = X86::INTEL_COREI7_SANDYBRIDGE;
700       break;
701     case 0x3a:
702     case 0x3e:              // Ivy Bridge EP
703       CPU = "ivybridge";
704       *Type = X86::INTEL_COREI7;
705       *Subtype = X86::INTEL_COREI7_IVYBRIDGE;
706       break;
707 
708     // Haswell:
709     case 0x3c:
710     case 0x3f:
711     case 0x45:
712     case 0x46:
713       CPU = "haswell";
714       *Type = X86::INTEL_COREI7;
715       *Subtype = X86::INTEL_COREI7_HASWELL;
716       break;
717 
718     // Broadwell:
719     case 0x3d:
720     case 0x47:
721     case 0x4f:
722     case 0x56:
723       CPU = "broadwell";
724       *Type = X86::INTEL_COREI7;
725       *Subtype = X86::INTEL_COREI7_BROADWELL;
726       break;
727 
728     // Skylake:
729     case 0x4e:              // Skylake mobile
730     case 0x5e:              // Skylake desktop
731     case 0x8e:              // Kaby Lake mobile
732     case 0x9e:              // Kaby Lake desktop
733     case 0xa5:              // Comet Lake-H/S
734     case 0xa6:              // Comet Lake-U
735       CPU = "skylake";
736       *Type = X86::INTEL_COREI7;
737       *Subtype = X86::INTEL_COREI7_SKYLAKE;
738       break;
739 
740     // Rocketlake:
741     case 0xa7:
742       CPU = "rocketlake";
743       *Type = X86::INTEL_COREI7;
744       *Subtype = X86::INTEL_COREI7_ROCKETLAKE;
745       break;
746 
747     // Skylake Xeon:
748     case 0x55:
749       *Type = X86::INTEL_COREI7;
750       if (testFeature(X86::FEATURE_AVX512BF16)) {
751         CPU = "cooperlake";
752         *Subtype = X86::INTEL_COREI7_COOPERLAKE;
753       } else if (testFeature(X86::FEATURE_AVX512VNNI)) {
754         CPU = "cascadelake";
755         *Subtype = X86::INTEL_COREI7_CASCADELAKE;
756       } else {
757         CPU = "skylake-avx512";
758         *Subtype = X86::INTEL_COREI7_SKYLAKE_AVX512;
759       }
760       break;
761 
762     // Cannonlake:
763     case 0x66:
764       CPU = "cannonlake";
765       *Type = X86::INTEL_COREI7;
766       *Subtype = X86::INTEL_COREI7_CANNONLAKE;
767       break;
768 
769     // Icelake:
770     case 0x7d:
771     case 0x7e:
772       CPU = "icelake-client";
773       *Type = X86::INTEL_COREI7;
774       *Subtype = X86::INTEL_COREI7_ICELAKE_CLIENT;
775       break;
776 
777     // Tigerlake:
778     case 0x8c:
779     case 0x8d:
780       CPU = "tigerlake";
781       *Type = X86::INTEL_COREI7;
782       *Subtype = X86::INTEL_COREI7_TIGERLAKE;
783       break;
784 
785     // Alderlake:
786     case 0x97:
787     case 0x9a:
788       CPU = "alderlake";
789       *Type = X86::INTEL_COREI7;
790       *Subtype = X86::INTEL_COREI7_ALDERLAKE;
791       break;
792 
793     // Icelake Xeon:
794     case 0x6a:
795     case 0x6c:
796       CPU = "icelake-server";
797       *Type = X86::INTEL_COREI7;
798       *Subtype = X86::INTEL_COREI7_ICELAKE_SERVER;
799       break;
800 
801     // Sapphire Rapids:
802     case 0x8f:
803       CPU = "sapphirerapids";
804       *Type = X86::INTEL_COREI7;
805       *Subtype = X86::INTEL_COREI7_SAPPHIRERAPIDS;
806       break;
807 
808     case 0x1c: // Most 45 nm Intel Atom processors
809     case 0x26: // 45 nm Atom Lincroft
810     case 0x27: // 32 nm Atom Medfield
811     case 0x35: // 32 nm Atom Midview
812     case 0x36: // 32 nm Atom Midview
813       CPU = "bonnell";
814       *Type = X86::INTEL_BONNELL;
815       break;
816 
817     // Atom Silvermont codes from the Intel software optimization guide.
818     case 0x37:
819     case 0x4a:
820     case 0x4d:
821     case 0x5a:
822     case 0x5d:
823     case 0x4c: // really airmont
824       CPU = "silvermont";
825       *Type = X86::INTEL_SILVERMONT;
826       break;
827     // Goldmont:
828     case 0x5c: // Apollo Lake
829     case 0x5f: // Denverton
830       CPU = "goldmont";
831       *Type = X86::INTEL_GOLDMONT;
832       break;
833     case 0x7a:
834       CPU = "goldmont-plus";
835       *Type = X86::INTEL_GOLDMONT_PLUS;
836       break;
837     case 0x86:
838       CPU = "tremont";
839       *Type = X86::INTEL_TREMONT;
840       break;
841 
842     // Xeon Phi (Knights Landing + Knights Mill):
843     case 0x57:
844       CPU = "knl";
845       *Type = X86::INTEL_KNL;
846       break;
847     case 0x85:
848       CPU = "knm";
849       *Type = X86::INTEL_KNM;
850       break;
851 
852     default: // Unknown family 6 CPU, try to guess.
853       // Don't both with Type/Subtype here, they aren't used by the caller.
854       // They're used above to keep the code in sync with compiler-rt.
855       // TODO detect tigerlake host from model
856       if (testFeature(X86::FEATURE_AVX512VP2INTERSECT)) {
857         CPU = "tigerlake";
858       } else if (testFeature(X86::FEATURE_AVX512VBMI2)) {
859         CPU = "icelake-client";
860       } else if (testFeature(X86::FEATURE_AVX512VBMI)) {
861         CPU = "cannonlake";
862       } else if (testFeature(X86::FEATURE_AVX512BF16)) {
863         CPU = "cooperlake";
864       } else if (testFeature(X86::FEATURE_AVX512VNNI)) {
865         CPU = "cascadelake";
866       } else if (testFeature(X86::FEATURE_AVX512VL)) {
867         CPU = "skylake-avx512";
868       } else if (testFeature(X86::FEATURE_AVX512ER)) {
869         CPU = "knl";
870       } else if (testFeature(X86::FEATURE_CLFLUSHOPT)) {
871         if (testFeature(X86::FEATURE_SHA))
872           CPU = "goldmont";
873         else
874           CPU = "skylake";
875       } else if (testFeature(X86::FEATURE_ADX)) {
876         CPU = "broadwell";
877       } else if (testFeature(X86::FEATURE_AVX2)) {
878         CPU = "haswell";
879       } else if (testFeature(X86::FEATURE_AVX)) {
880         CPU = "sandybridge";
881       } else if (testFeature(X86::FEATURE_SSE4_2)) {
882         if (testFeature(X86::FEATURE_MOVBE))
883           CPU = "silvermont";
884         else
885           CPU = "nehalem";
886       } else if (testFeature(X86::FEATURE_SSE4_1)) {
887         CPU = "penryn";
888       } else if (testFeature(X86::FEATURE_SSSE3)) {
889         if (testFeature(X86::FEATURE_MOVBE))
890           CPU = "bonnell";
891         else
892           CPU = "core2";
893       } else if (testFeature(X86::FEATURE_64BIT)) {
894         CPU = "core2";
895       } else if (testFeature(X86::FEATURE_SSE3)) {
896         CPU = "yonah";
897       } else if (testFeature(X86::FEATURE_SSE2)) {
898         CPU = "pentium-m";
899       } else if (testFeature(X86::FEATURE_SSE)) {
900         CPU = "pentium3";
901       } else if (testFeature(X86::FEATURE_MMX)) {
902         CPU = "pentium2";
903       } else {
904         CPU = "pentiumpro";
905       }
906       break;
907     }
908     break;
909   case 15: {
910     if (testFeature(X86::FEATURE_64BIT)) {
911       CPU = "nocona";
912       break;
913     }
914     if (testFeature(X86::FEATURE_SSE3)) {
915       CPU = "prescott";
916       break;
917     }
918     CPU = "pentium4";
919     break;
920   }
921   default:
922     break; // Unknown.
923   }
924 
925   return CPU;
926 }
927 
928 static StringRef
929 getAMDProcessorTypeAndSubtype(unsigned Family, unsigned Model,
930                               const unsigned *Features,
931                               unsigned *Type, unsigned *Subtype) {
932   auto testFeature = [&](unsigned F) {
933     return (Features[F / 32] & (1U << (F % 32))) != 0;
934   };
935 
936   StringRef CPU;
937 
938   switch (Family) {
939   case 4:
940     CPU = "i486";
941     break;
942   case 5:
943     CPU = "pentium";
944     switch (Model) {
945     case 6:
946     case 7:
947       CPU = "k6";
948       break;
949     case 8:
950       CPU = "k6-2";
951       break;
952     case 9:
953     case 13:
954       CPU = "k6-3";
955       break;
956     case 10:
957       CPU = "geode";
958       break;
959     }
960     break;
961   case 6:
962     if (testFeature(X86::FEATURE_SSE)) {
963       CPU = "athlon-xp";
964       break;
965     }
966     CPU = "athlon";
967     break;
968   case 15:
969     if (testFeature(X86::FEATURE_SSE3)) {
970       CPU = "k8-sse3";
971       break;
972     }
973     CPU = "k8";
974     break;
975   case 16:
976     CPU = "amdfam10";
977     *Type = X86::AMDFAM10H; // "amdfam10"
978     switch (Model) {
979     case 2:
980       *Subtype = X86::AMDFAM10H_BARCELONA;
981       break;
982     case 4:
983       *Subtype = X86::AMDFAM10H_SHANGHAI;
984       break;
985     case 8:
986       *Subtype = X86::AMDFAM10H_ISTANBUL;
987       break;
988     }
989     break;
990   case 20:
991     CPU = "btver1";
992     *Type = X86::AMD_BTVER1;
993     break;
994   case 21:
995     CPU = "bdver1";
996     *Type = X86::AMDFAM15H;
997     if (Model >= 0x60 && Model <= 0x7f) {
998       CPU = "bdver4";
999       *Subtype = X86::AMDFAM15H_BDVER4;
1000       break; // 60h-7Fh: Excavator
1001     }
1002     if (Model >= 0x30 && Model <= 0x3f) {
1003       CPU = "bdver3";
1004       *Subtype = X86::AMDFAM15H_BDVER3;
1005       break; // 30h-3Fh: Steamroller
1006     }
1007     if ((Model >= 0x10 && Model <= 0x1f) || Model == 0x02) {
1008       CPU = "bdver2";
1009       *Subtype = X86::AMDFAM15H_BDVER2;
1010       break; // 02h, 10h-1Fh: Piledriver
1011     }
1012     if (Model <= 0x0f) {
1013       *Subtype = X86::AMDFAM15H_BDVER1;
1014       break; // 00h-0Fh: Bulldozer
1015     }
1016     break;
1017   case 22:
1018     CPU = "btver2";
1019     *Type = X86::AMD_BTVER2;
1020     break;
1021   case 23:
1022     CPU = "znver1";
1023     *Type = X86::AMDFAM17H;
1024     if ((Model >= 0x30 && Model <= 0x3f) || Model == 0x71) {
1025       CPU = "znver2";
1026       *Subtype = X86::AMDFAM17H_ZNVER2;
1027       break; // 30h-3fh, 71h: Zen2
1028     }
1029     if (Model <= 0x0f) {
1030       *Subtype = X86::AMDFAM17H_ZNVER1;
1031       break; // 00h-0Fh: Zen1
1032     }
1033     break;
1034   case 25:
1035     CPU = "znver3";
1036     *Type = X86::AMDFAM19H;
1037     if (Model <= 0x0f || Model == 0x21) {
1038       *Subtype = X86::AMDFAM19H_ZNVER3;
1039       break; // 00h-0Fh, 21h: Zen3
1040     }
1041     break;
1042   default:
1043     break; // Unknown AMD CPU.
1044   }
1045 
1046   return CPU;
1047 }
1048 
1049 static void getAvailableFeatures(unsigned ECX, unsigned EDX, unsigned MaxLeaf,
1050                                  unsigned *Features) {
1051   unsigned EAX, EBX;
1052 
1053   auto setFeature = [&](unsigned F) {
1054     Features[F / 32] |= 1U << (F % 32);
1055   };
1056 
1057   if ((EDX >> 15) & 1)
1058     setFeature(X86::FEATURE_CMOV);
1059   if ((EDX >> 23) & 1)
1060     setFeature(X86::FEATURE_MMX);
1061   if ((EDX >> 25) & 1)
1062     setFeature(X86::FEATURE_SSE);
1063   if ((EDX >> 26) & 1)
1064     setFeature(X86::FEATURE_SSE2);
1065 
1066   if ((ECX >> 0) & 1)
1067     setFeature(X86::FEATURE_SSE3);
1068   if ((ECX >> 1) & 1)
1069     setFeature(X86::FEATURE_PCLMUL);
1070   if ((ECX >> 9) & 1)
1071     setFeature(X86::FEATURE_SSSE3);
1072   if ((ECX >> 12) & 1)
1073     setFeature(X86::FEATURE_FMA);
1074   if ((ECX >> 19) & 1)
1075     setFeature(X86::FEATURE_SSE4_1);
1076   if ((ECX >> 20) & 1) {
1077     setFeature(X86::FEATURE_SSE4_2);
1078     setFeature(X86::FEATURE_CRC32);
1079   }
1080   if ((ECX >> 23) & 1)
1081     setFeature(X86::FEATURE_POPCNT);
1082   if ((ECX >> 25) & 1)
1083     setFeature(X86::FEATURE_AES);
1084 
1085   if ((ECX >> 22) & 1)
1086     setFeature(X86::FEATURE_MOVBE);
1087 
1088   // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
1089   // indicates that the AVX registers will be saved and restored on context
1090   // switch, then we have full AVX support.
1091   const unsigned AVXBits = (1 << 27) | (1 << 28);
1092   bool HasAVX = ((ECX & AVXBits) == AVXBits) && !getX86XCR0(&EAX, &EDX) &&
1093                 ((EAX & 0x6) == 0x6);
1094 #if defined(__APPLE__)
1095   // Darwin lazily saves the AVX512 context on first use: trust that the OS will
1096   // save the AVX512 context if we use AVX512 instructions, even the bit is not
1097   // set right now.
1098   bool HasAVX512Save = true;
1099 #else
1100   // AVX512 requires additional context to be saved by the OS.
1101   bool HasAVX512Save = HasAVX && ((EAX & 0xe0) == 0xe0);
1102 #endif
1103 
1104   if (HasAVX)
1105     setFeature(X86::FEATURE_AVX);
1106 
1107   bool HasLeaf7 =
1108       MaxLeaf >= 0x7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
1109 
1110   if (HasLeaf7 && ((EBX >> 3) & 1))
1111     setFeature(X86::FEATURE_BMI);
1112   if (HasLeaf7 && ((EBX >> 5) & 1) && HasAVX)
1113     setFeature(X86::FEATURE_AVX2);
1114   if (HasLeaf7 && ((EBX >> 8) & 1))
1115     setFeature(X86::FEATURE_BMI2);
1116   if (HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save)
1117     setFeature(X86::FEATURE_AVX512F);
1118   if (HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save)
1119     setFeature(X86::FEATURE_AVX512DQ);
1120   if (HasLeaf7 && ((EBX >> 19) & 1))
1121     setFeature(X86::FEATURE_ADX);
1122   if (HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save)
1123     setFeature(X86::FEATURE_AVX512IFMA);
1124   if (HasLeaf7 && ((EBX >> 23) & 1))
1125     setFeature(X86::FEATURE_CLFLUSHOPT);
1126   if (HasLeaf7 && ((EBX >> 26) & 1) && HasAVX512Save)
1127     setFeature(X86::FEATURE_AVX512PF);
1128   if (HasLeaf7 && ((EBX >> 27) & 1) && HasAVX512Save)
1129     setFeature(X86::FEATURE_AVX512ER);
1130   if (HasLeaf7 && ((EBX >> 28) & 1) && HasAVX512Save)
1131     setFeature(X86::FEATURE_AVX512CD);
1132   if (HasLeaf7 && ((EBX >> 29) & 1))
1133     setFeature(X86::FEATURE_SHA);
1134   if (HasLeaf7 && ((EBX >> 30) & 1) && HasAVX512Save)
1135     setFeature(X86::FEATURE_AVX512BW);
1136   if (HasLeaf7 && ((EBX >> 31) & 1) && HasAVX512Save)
1137     setFeature(X86::FEATURE_AVX512VL);
1138 
1139   if (HasLeaf7 && ((ECX >> 1) & 1) && HasAVX512Save)
1140     setFeature(X86::FEATURE_AVX512VBMI);
1141   if (HasLeaf7 && ((ECX >> 6) & 1) && HasAVX512Save)
1142     setFeature(X86::FEATURE_AVX512VBMI2);
1143   if (HasLeaf7 && ((ECX >> 8) & 1))
1144     setFeature(X86::FEATURE_GFNI);
1145   if (HasLeaf7 && ((ECX >> 10) & 1) && HasAVX)
1146     setFeature(X86::FEATURE_VPCLMULQDQ);
1147   if (HasLeaf7 && ((ECX >> 11) & 1) && HasAVX512Save)
1148     setFeature(X86::FEATURE_AVX512VNNI);
1149   if (HasLeaf7 && ((ECX >> 12) & 1) && HasAVX512Save)
1150     setFeature(X86::FEATURE_AVX512BITALG);
1151   if (HasLeaf7 && ((ECX >> 14) & 1) && HasAVX512Save)
1152     setFeature(X86::FEATURE_AVX512VPOPCNTDQ);
1153 
1154   if (HasLeaf7 && ((EDX >> 2) & 1) && HasAVX512Save)
1155     setFeature(X86::FEATURE_AVX5124VNNIW);
1156   if (HasLeaf7 && ((EDX >> 3) & 1) && HasAVX512Save)
1157     setFeature(X86::FEATURE_AVX5124FMAPS);
1158   if (HasLeaf7 && ((EDX >> 8) & 1) && HasAVX512Save)
1159     setFeature(X86::FEATURE_AVX512VP2INTERSECT);
1160 
1161   bool HasLeaf7Subleaf1 =
1162       MaxLeaf >= 7 && !getX86CpuIDAndInfoEx(0x7, 0x1, &EAX, &EBX, &ECX, &EDX);
1163   if (HasLeaf7Subleaf1 && ((EAX >> 5) & 1) && HasAVX512Save)
1164     setFeature(X86::FEATURE_AVX512BF16);
1165 
1166   unsigned MaxExtLevel;
1167   getX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
1168 
1169   bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
1170                      !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
1171   if (HasExtLeaf1 && ((ECX >> 6) & 1))
1172     setFeature(X86::FEATURE_SSE4_A);
1173   if (HasExtLeaf1 && ((ECX >> 11) & 1))
1174     setFeature(X86::FEATURE_XOP);
1175   if (HasExtLeaf1 && ((ECX >> 16) & 1))
1176     setFeature(X86::FEATURE_FMA4);
1177 
1178   if (HasExtLeaf1 && ((EDX >> 29) & 1))
1179     setFeature(X86::FEATURE_64BIT);
1180 }
1181 
1182 StringRef sys::getHostCPUName() {
1183   unsigned MaxLeaf = 0;
1184   const VendorSignatures Vendor = getVendorSignature(&MaxLeaf);
1185   if (Vendor == VendorSignatures::UNKNOWN)
1186     return "generic";
1187 
1188   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
1189   getX86CpuIDAndInfo(0x1, &EAX, &EBX, &ECX, &EDX);
1190 
1191   unsigned Family = 0, Model = 0;
1192   unsigned Features[(X86::CPU_FEATURE_MAX + 31) / 32] = {0};
1193   detectX86FamilyModel(EAX, &Family, &Model);
1194   getAvailableFeatures(ECX, EDX, MaxLeaf, Features);
1195 
1196   // These aren't consumed in this file, but we try to keep some source code the
1197   // same or similar to compiler-rt.
1198   unsigned Type = 0;
1199   unsigned Subtype = 0;
1200 
1201   StringRef CPU;
1202 
1203   if (Vendor == VendorSignatures::GENUINE_INTEL) {
1204     CPU = getIntelProcessorTypeAndSubtype(Family, Model, Features, &Type,
1205                                           &Subtype);
1206   } else if (Vendor == VendorSignatures::AUTHENTIC_AMD) {
1207     CPU = getAMDProcessorTypeAndSubtype(Family, Model, Features, &Type,
1208                                         &Subtype);
1209   }
1210 
1211   if (!CPU.empty())
1212     return CPU;
1213 
1214   return "generic";
1215 }
1216 
1217 #elif defined(__APPLE__) && (defined(__ppc__) || defined(__powerpc__))
1218 StringRef sys::getHostCPUName() {
1219   host_basic_info_data_t hostInfo;
1220   mach_msg_type_number_t infoCount;
1221 
1222   infoCount = HOST_BASIC_INFO_COUNT;
1223   mach_port_t hostPort = mach_host_self();
1224   host_info(hostPort, HOST_BASIC_INFO, (host_info_t)&hostInfo,
1225             &infoCount);
1226   mach_port_deallocate(mach_task_self(), hostPort);
1227 
1228   if (hostInfo.cpu_type != CPU_TYPE_POWERPC)
1229     return "generic";
1230 
1231   switch (hostInfo.cpu_subtype) {
1232   case CPU_SUBTYPE_POWERPC_601:
1233     return "601";
1234   case CPU_SUBTYPE_POWERPC_602:
1235     return "602";
1236   case CPU_SUBTYPE_POWERPC_603:
1237     return "603";
1238   case CPU_SUBTYPE_POWERPC_603e:
1239     return "603e";
1240   case CPU_SUBTYPE_POWERPC_603ev:
1241     return "603ev";
1242   case CPU_SUBTYPE_POWERPC_604:
1243     return "604";
1244   case CPU_SUBTYPE_POWERPC_604e:
1245     return "604e";
1246   case CPU_SUBTYPE_POWERPC_620:
1247     return "620";
1248   case CPU_SUBTYPE_POWERPC_750:
1249     return "750";
1250   case CPU_SUBTYPE_POWERPC_7400:
1251     return "7400";
1252   case CPU_SUBTYPE_POWERPC_7450:
1253     return "7450";
1254   case CPU_SUBTYPE_POWERPC_970:
1255     return "970";
1256   default:;
1257   }
1258 
1259   return "generic";
1260 }
1261 #elif defined(__linux__) && (defined(__ppc__) || defined(__powerpc__))
1262 StringRef sys::getHostCPUName() {
1263   std::unique_ptr<llvm::MemoryBuffer> P = getProcCpuinfoContent();
1264   StringRef Content = P ? P->getBuffer() : "";
1265   return detail::getHostCPUNameForPowerPC(Content);
1266 }
1267 #elif defined(__linux__) && (defined(__arm__) || defined(__aarch64__))
1268 StringRef sys::getHostCPUName() {
1269   std::unique_ptr<llvm::MemoryBuffer> P = getProcCpuinfoContent();
1270   StringRef Content = P ? P->getBuffer() : "";
1271   return detail::getHostCPUNameForARM(Content);
1272 }
1273 #elif defined(__linux__) && defined(__s390x__)
1274 StringRef sys::getHostCPUName() {
1275   std::unique_ptr<llvm::MemoryBuffer> P = getProcCpuinfoContent();
1276   StringRef Content = P ? P->getBuffer() : "";
1277   return detail::getHostCPUNameForS390x(Content);
1278 }
1279 #elif defined(__MVS__)
1280 StringRef sys::getHostCPUName() {
1281   // Get pointer to Communications Vector Table (CVT).
1282   // The pointer is located at offset 16 of the Prefixed Save Area (PSA).
1283   // It is stored as 31 bit pointer and will be zero-extended to 64 bit.
1284   int *StartToCVTOffset = reinterpret_cast<int *>(0x10);
1285   // Since its stored as a 31-bit pointer, get the 4 bytes from the start
1286   // of address.
1287   int ReadValue = *StartToCVTOffset;
1288   // Explicitly clear the high order bit.
1289   ReadValue = (ReadValue & 0x7FFFFFFF);
1290   char *CVT = reinterpret_cast<char *>(ReadValue);
1291   // The model number is located in the CVT prefix at offset -6 and stored as
1292   // signless packed decimal.
1293   uint16_t Id = *(uint16_t *)&CVT[-6];
1294   // Convert number to integer.
1295   Id = decodePackedBCD<uint16_t>(Id, false);
1296   // Check for vector support. It's stored in field CVTFLAG5 (offset 244),
1297   // bit CVTVEF (X'80'). The facilities list is part of the PSA but the vector
1298   // extension can only be used if bit CVTVEF is on.
1299   bool HaveVectorSupport = CVT[244] & 0x80;
1300   return getCPUNameFromS390Model(Id, HaveVectorSupport);
1301 }
1302 #elif defined(__APPLE__) && (defined(__arm__) || defined(__aarch64__))
1303 #define CPUFAMILY_ARM_SWIFT 0x1e2d6381
1304 #define CPUFAMILY_ARM_CYCLONE 0x37a09642
1305 #define CPUFAMILY_ARM_TYPHOON 0x2c91a47e
1306 #define CPUFAMILY_ARM_TWISTER 0x92fb37c8
1307 #define CPUFAMILY_ARM_HURRICANE 0x67ceee93
1308 #define CPUFAMILY_ARM_MONSOON_MISTRAL 0xe81e7ef6
1309 #define CPUFAMILY_ARM_VORTEX_TEMPEST 0x07d34b9f
1310 #define CPUFAMILY_ARM_LIGHTNING_THUNDER 0x462504d2
1311 #define CPUFAMILY_ARM_FIRESTORM_ICESTORM 0x1b588bb3
1312 
1313 StringRef sys::getHostCPUName() {
1314   uint32_t Family;
1315   size_t Length = sizeof(Family);
1316   sysctlbyname("hw.cpufamily", &Family, &Length, NULL, 0);
1317 
1318   switch (Family) {
1319   case CPUFAMILY_ARM_SWIFT:
1320     return "swift";
1321   case CPUFAMILY_ARM_CYCLONE:
1322     return "apple-a7";
1323   case CPUFAMILY_ARM_TYPHOON:
1324     return "apple-a8";
1325   case CPUFAMILY_ARM_TWISTER:
1326     return "apple-a9";
1327   case CPUFAMILY_ARM_HURRICANE:
1328     return "apple-a10";
1329   case CPUFAMILY_ARM_MONSOON_MISTRAL:
1330     return "apple-a11";
1331   case CPUFAMILY_ARM_VORTEX_TEMPEST:
1332     return "apple-a12";
1333   case CPUFAMILY_ARM_LIGHTNING_THUNDER:
1334     return "apple-a13";
1335   case CPUFAMILY_ARM_FIRESTORM_ICESTORM:
1336     return "apple-m1";
1337   default:
1338     // Default to the newest CPU we know about.
1339     return "apple-m1";
1340   }
1341 }
1342 #elif defined(_AIX)
1343 StringRef sys::getHostCPUName() {
1344   switch (_system_configuration.implementation) {
1345   case POWER_4:
1346     if (_system_configuration.version == PV_4_3)
1347       return "970";
1348     return "pwr4";
1349   case POWER_5:
1350     if (_system_configuration.version == PV_5)
1351       return "pwr5";
1352     return "pwr5x";
1353   case POWER_6:
1354     if (_system_configuration.version == PV_6_Compat)
1355       return "pwr6";
1356     return "pwr6x";
1357   case POWER_7:
1358     return "pwr7";
1359   case POWER_8:
1360     return "pwr8";
1361   case POWER_9:
1362     return "pwr9";
1363 // TODO: simplify this once the macro is available in all OS levels.
1364 #ifdef POWER_10
1365   case POWER_10:
1366 #else
1367   case 0x40000:
1368 #endif
1369     return "pwr10";
1370   default:
1371     return "generic";
1372   }
1373 }
1374 #elif defined(__riscv)
1375 StringRef sys::getHostCPUName() {
1376 #if __riscv_xlen == 64
1377   return "generic-rv64";
1378 #elif __riscv_xlen == 32
1379   return "generic-rv32";
1380 #else
1381 #error "Unhandled value of __riscv_xlen"
1382 #endif
1383 }
1384 #else
1385 StringRef sys::getHostCPUName() { return "generic"; }
1386 namespace llvm {
1387 namespace sys {
1388 namespace detail {
1389 namespace x86 {
1390 
1391 VendorSignatures getVendorSignature(unsigned *MaxLeaf) {
1392   return VendorSignatures::UNKNOWN;
1393 }
1394 
1395 } // namespace x86
1396 } // namespace detail
1397 } // namespace sys
1398 } // namespace llvm
1399 #endif
1400 
1401 #if defined(__linux__) && (defined(__i386__) || defined(__x86_64__))
1402 // On Linux, the number of physical cores can be computed from /proc/cpuinfo,
1403 // using the number of unique physical/core id pairs. The following
1404 // implementation reads the /proc/cpuinfo format on an x86_64 system.
1405 int computeHostNumPhysicalCores() {
1406   // Enabled represents the number of physical id/core id pairs with at least
1407   // one processor id enabled by the CPU affinity mask.
1408   cpu_set_t Affinity, Enabled;
1409   if (sched_getaffinity(0, sizeof(Affinity), &Affinity) != 0)
1410     return -1;
1411   CPU_ZERO(&Enabled);
1412 
1413   // Read /proc/cpuinfo as a stream (until EOF reached). It cannot be
1414   // mmapped because it appears to have 0 size.
1415   llvm::ErrorOr<std::unique_ptr<llvm::MemoryBuffer>> Text =
1416       llvm::MemoryBuffer::getFileAsStream("/proc/cpuinfo");
1417   if (std::error_code EC = Text.getError()) {
1418     llvm::errs() << "Can't read "
1419                  << "/proc/cpuinfo: " << EC.message() << "\n";
1420     return -1;
1421   }
1422   SmallVector<StringRef, 8> strs;
1423   (*Text)->getBuffer().split(strs, "\n", /*MaxSplit=*/-1,
1424                              /*KeepEmpty=*/false);
1425   int CurProcessor = -1;
1426   int CurPhysicalId = -1;
1427   int CurSiblings = -1;
1428   int CurCoreId = -1;
1429   for (StringRef Line : strs) {
1430     std::pair<StringRef, StringRef> Data = Line.split(':');
1431     auto Name = Data.first.trim();
1432     auto Val = Data.second.trim();
1433     // These fields are available if the kernel is configured with CONFIG_SMP.
1434     if (Name == "processor")
1435       Val.getAsInteger(10, CurProcessor);
1436     else if (Name == "physical id")
1437       Val.getAsInteger(10, CurPhysicalId);
1438     else if (Name == "siblings")
1439       Val.getAsInteger(10, CurSiblings);
1440     else if (Name == "core id") {
1441       Val.getAsInteger(10, CurCoreId);
1442       // The processor id corresponds to an index into cpu_set_t.
1443       if (CPU_ISSET(CurProcessor, &Affinity))
1444         CPU_SET(CurPhysicalId * CurSiblings + CurCoreId, &Enabled);
1445     }
1446   }
1447   return CPU_COUNT(&Enabled);
1448 }
1449 #elif defined(__linux__) && defined(__powerpc__)
1450 int computeHostNumPhysicalCores() {
1451   cpu_set_t Affinity;
1452   if (sched_getaffinity(0, sizeof(Affinity), &Affinity) == 0)
1453     return CPU_COUNT(&Affinity);
1454 
1455   // The call to sched_getaffinity() may have failed because the Affinity
1456   // mask is too small for the number of CPU's on the system (i.e. the
1457   // system has more than 1024 CPUs). Allocate a mask large enough for
1458   // twice as many CPUs.
1459   cpu_set_t *DynAffinity;
1460   DynAffinity = CPU_ALLOC(2048);
1461   if (sched_getaffinity(0, CPU_ALLOC_SIZE(2048), DynAffinity) == 0) {
1462     int NumCPUs = CPU_COUNT(DynAffinity);
1463     CPU_FREE(DynAffinity);
1464     return NumCPUs;
1465   }
1466   return -1;
1467 }
1468 #elif defined(__linux__) && defined(__s390x__)
1469 int computeHostNumPhysicalCores() { return sysconf(_SC_NPROCESSORS_ONLN); }
1470 #elif defined(__APPLE__)
1471 // Gets the number of *physical cores* on the machine.
1472 int computeHostNumPhysicalCores() {
1473   uint32_t count;
1474   size_t len = sizeof(count);
1475   sysctlbyname("hw.physicalcpu", &count, &len, NULL, 0);
1476   if (count < 1) {
1477     int nm[2];
1478     nm[0] = CTL_HW;
1479     nm[1] = HW_AVAILCPU;
1480     sysctl(nm, 2, &count, &len, NULL, 0);
1481     if (count < 1)
1482       return -1;
1483   }
1484   return count;
1485 }
1486 #elif defined(__MVS__)
1487 int computeHostNumPhysicalCores() {
1488   enum {
1489     // Byte offset of the pointer to the Communications Vector Table (CVT) in
1490     // the Prefixed Save Area (PSA). The table entry is a 31-bit pointer and
1491     // will be zero-extended to uintptr_t.
1492     FLCCVT = 16,
1493     // Byte offset of the pointer to the Common System Data Area (CSD) in the
1494     // CVT. The table entry is a 31-bit pointer and will be zero-extended to
1495     // uintptr_t.
1496     CVTCSD = 660,
1497     // Byte offset to the number of live CPs in the LPAR, stored as a signed
1498     // 32-bit value in the table.
1499     CSD_NUMBER_ONLINE_STANDARD_CPS = 264,
1500   };
1501   char *PSA = 0;
1502   char *CVT = reinterpret_cast<char *>(
1503       static_cast<uintptr_t>(reinterpret_cast<unsigned int &>(PSA[FLCCVT])));
1504   char *CSD = reinterpret_cast<char *>(
1505       static_cast<uintptr_t>(reinterpret_cast<unsigned int &>(CVT[CVTCSD])));
1506   return reinterpret_cast<int &>(CSD[CSD_NUMBER_ONLINE_STANDARD_CPS]);
1507 }
1508 #elif defined(_WIN32) && LLVM_ENABLE_THREADS != 0
1509 // Defined in llvm/lib/Support/Windows/Threading.inc
1510 int computeHostNumPhysicalCores();
1511 #else
1512 // On other systems, return -1 to indicate unknown.
1513 static int computeHostNumPhysicalCores() { return -1; }
1514 #endif
1515 
1516 int sys::getHostNumPhysicalCores() {
1517   static int NumCores = computeHostNumPhysicalCores();
1518   return NumCores;
1519 }
1520 
1521 #if defined(__i386__) || defined(_M_IX86) || \
1522     defined(__x86_64__) || defined(_M_X64)
1523 bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
1524   unsigned EAX = 0, EBX = 0, ECX = 0, EDX = 0;
1525   unsigned MaxLevel;
1526 
1527   if (getX86CpuIDAndInfo(0, &MaxLevel, &EBX, &ECX, &EDX) || MaxLevel < 1)
1528     return false;
1529 
1530   getX86CpuIDAndInfo(1, &EAX, &EBX, &ECX, &EDX);
1531 
1532   Features["cx8"]    = (EDX >>  8) & 1;
1533   Features["cmov"]   = (EDX >> 15) & 1;
1534   Features["mmx"]    = (EDX >> 23) & 1;
1535   Features["fxsr"]   = (EDX >> 24) & 1;
1536   Features["sse"]    = (EDX >> 25) & 1;
1537   Features["sse2"]   = (EDX >> 26) & 1;
1538 
1539   Features["sse3"]   = (ECX >>  0) & 1;
1540   Features["pclmul"] = (ECX >>  1) & 1;
1541   Features["ssse3"]  = (ECX >>  9) & 1;
1542   Features["cx16"]   = (ECX >> 13) & 1;
1543   Features["sse4.1"] = (ECX >> 19) & 1;
1544   Features["sse4.2"] = (ECX >> 20) & 1;
1545   Features["crc32"]  = Features["sse4.2"];
1546   Features["movbe"]  = (ECX >> 22) & 1;
1547   Features["popcnt"] = (ECX >> 23) & 1;
1548   Features["aes"]    = (ECX >> 25) & 1;
1549   Features["rdrnd"]  = (ECX >> 30) & 1;
1550 
1551   // If CPUID indicates support for XSAVE, XRESTORE and AVX, and XGETBV
1552   // indicates that the AVX registers will be saved and restored on context
1553   // switch, then we have full AVX support.
1554   bool HasXSave = ((ECX >> 27) & 1) && !getX86XCR0(&EAX, &EDX);
1555   bool HasAVXSave = HasXSave && ((ECX >> 28) & 1) && ((EAX & 0x6) == 0x6);
1556 #if defined(__APPLE__)
1557   // Darwin lazily saves the AVX512 context on first use: trust that the OS will
1558   // save the AVX512 context if we use AVX512 instructions, even the bit is not
1559   // set right now.
1560   bool HasAVX512Save = true;
1561 #else
1562   // AVX512 requires additional context to be saved by the OS.
1563   bool HasAVX512Save = HasAVXSave && ((EAX & 0xe0) == 0xe0);
1564 #endif
1565   // AMX requires additional context to be saved by the OS.
1566   const unsigned AMXBits = (1 << 17) | (1 << 18);
1567   bool HasAMXSave = HasXSave && ((EAX & AMXBits) == AMXBits);
1568 
1569   Features["avx"]   = HasAVXSave;
1570   Features["fma"]   = ((ECX >> 12) & 1) && HasAVXSave;
1571   // Only enable XSAVE if OS has enabled support for saving YMM state.
1572   Features["xsave"] = ((ECX >> 26) & 1) && HasAVXSave;
1573   Features["f16c"]  = ((ECX >> 29) & 1) && HasAVXSave;
1574 
1575   unsigned MaxExtLevel;
1576   getX86CpuIDAndInfo(0x80000000, &MaxExtLevel, &EBX, &ECX, &EDX);
1577 
1578   bool HasExtLeaf1 = MaxExtLevel >= 0x80000001 &&
1579                      !getX86CpuIDAndInfo(0x80000001, &EAX, &EBX, &ECX, &EDX);
1580   Features["sahf"]   = HasExtLeaf1 && ((ECX >>  0) & 1);
1581   Features["lzcnt"]  = HasExtLeaf1 && ((ECX >>  5) & 1);
1582   Features["sse4a"]  = HasExtLeaf1 && ((ECX >>  6) & 1);
1583   Features["prfchw"] = HasExtLeaf1 && ((ECX >>  8) & 1);
1584   Features["xop"]    = HasExtLeaf1 && ((ECX >> 11) & 1) && HasAVXSave;
1585   Features["lwp"]    = HasExtLeaf1 && ((ECX >> 15) & 1);
1586   Features["fma4"]   = HasExtLeaf1 && ((ECX >> 16) & 1) && HasAVXSave;
1587   Features["tbm"]    = HasExtLeaf1 && ((ECX >> 21) & 1);
1588   Features["mwaitx"] = HasExtLeaf1 && ((ECX >> 29) & 1);
1589 
1590   Features["64bit"]  = HasExtLeaf1 && ((EDX >> 29) & 1);
1591 
1592   // Miscellaneous memory related features, detected by
1593   // using the 0x80000008 leaf of the CPUID instruction
1594   bool HasExtLeaf8 = MaxExtLevel >= 0x80000008 &&
1595                      !getX86CpuIDAndInfo(0x80000008, &EAX, &EBX, &ECX, &EDX);
1596   Features["clzero"]   = HasExtLeaf8 && ((EBX >> 0) & 1);
1597   Features["wbnoinvd"] = HasExtLeaf8 && ((EBX >> 9) & 1);
1598 
1599   bool HasLeaf7 =
1600       MaxLevel >= 7 && !getX86CpuIDAndInfoEx(0x7, 0x0, &EAX, &EBX, &ECX, &EDX);
1601 
1602   Features["fsgsbase"]   = HasLeaf7 && ((EBX >>  0) & 1);
1603   Features["sgx"]        = HasLeaf7 && ((EBX >>  2) & 1);
1604   Features["bmi"]        = HasLeaf7 && ((EBX >>  3) & 1);
1605   // AVX2 is only supported if we have the OS save support from AVX.
1606   Features["avx2"]       = HasLeaf7 && ((EBX >>  5) & 1) && HasAVXSave;
1607   Features["bmi2"]       = HasLeaf7 && ((EBX >>  8) & 1);
1608   Features["invpcid"]    = HasLeaf7 && ((EBX >> 10) & 1);
1609   Features["rtm"]        = HasLeaf7 && ((EBX >> 11) & 1);
1610   // AVX512 is only supported if the OS supports the context save for it.
1611   Features["avx512f"]    = HasLeaf7 && ((EBX >> 16) & 1) && HasAVX512Save;
1612   Features["avx512dq"]   = HasLeaf7 && ((EBX >> 17) & 1) && HasAVX512Save;
1613   Features["rdseed"]     = HasLeaf7 && ((EBX >> 18) & 1);
1614   Features["adx"]        = HasLeaf7 && ((EBX >> 19) & 1);
1615   Features["avx512ifma"] = HasLeaf7 && ((EBX >> 21) & 1) && HasAVX512Save;
1616   Features["clflushopt"] = HasLeaf7 && ((EBX >> 23) & 1);
1617   Features["clwb"]       = HasLeaf7 && ((EBX >> 24) & 1);
1618   Features["avx512pf"]   = HasLeaf7 && ((EBX >> 26) & 1) && HasAVX512Save;
1619   Features["avx512er"]   = HasLeaf7 && ((EBX >> 27) & 1) && HasAVX512Save;
1620   Features["avx512cd"]   = HasLeaf7 && ((EBX >> 28) & 1) && HasAVX512Save;
1621   Features["sha"]        = HasLeaf7 && ((EBX >> 29) & 1);
1622   Features["avx512bw"]   = HasLeaf7 && ((EBX >> 30) & 1) && HasAVX512Save;
1623   Features["avx512vl"]   = HasLeaf7 && ((EBX >> 31) & 1) && HasAVX512Save;
1624 
1625   Features["prefetchwt1"]     = HasLeaf7 && ((ECX >>  0) & 1);
1626   Features["avx512vbmi"]      = HasLeaf7 && ((ECX >>  1) & 1) && HasAVX512Save;
1627   Features["pku"]             = HasLeaf7 && ((ECX >>  4) & 1);
1628   Features["waitpkg"]         = HasLeaf7 && ((ECX >>  5) & 1);
1629   Features["avx512vbmi2"]     = HasLeaf7 && ((ECX >>  6) & 1) && HasAVX512Save;
1630   Features["shstk"]           = HasLeaf7 && ((ECX >>  7) & 1);
1631   Features["gfni"]            = HasLeaf7 && ((ECX >>  8) & 1);
1632   Features["vaes"]            = HasLeaf7 && ((ECX >>  9) & 1) && HasAVXSave;
1633   Features["vpclmulqdq"]      = HasLeaf7 && ((ECX >> 10) & 1) && HasAVXSave;
1634   Features["avx512vnni"]      = HasLeaf7 && ((ECX >> 11) & 1) && HasAVX512Save;
1635   Features["avx512bitalg"]    = HasLeaf7 && ((ECX >> 12) & 1) && HasAVX512Save;
1636   Features["avx512vpopcntdq"] = HasLeaf7 && ((ECX >> 14) & 1) && HasAVX512Save;
1637   Features["rdpid"]           = HasLeaf7 && ((ECX >> 22) & 1);
1638   Features["kl"]              = HasLeaf7 && ((ECX >> 23) & 1); // key locker
1639   Features["cldemote"]        = HasLeaf7 && ((ECX >> 25) & 1);
1640   Features["movdiri"]         = HasLeaf7 && ((ECX >> 27) & 1);
1641   Features["movdir64b"]       = HasLeaf7 && ((ECX >> 28) & 1);
1642   Features["enqcmd"]          = HasLeaf7 && ((ECX >> 29) & 1);
1643 
1644   Features["uintr"]           = HasLeaf7 && ((EDX >> 5) & 1);
1645   Features["avx512vp2intersect"] =
1646       HasLeaf7 && ((EDX >> 8) & 1) && HasAVX512Save;
1647   Features["serialize"]       = HasLeaf7 && ((EDX >> 14) & 1);
1648   Features["tsxldtrk"]        = HasLeaf7 && ((EDX >> 16) & 1);
1649   // There are two CPUID leafs which information associated with the pconfig
1650   // instruction:
1651   // EAX=0x7, ECX=0x0 indicates the availability of the instruction (via the 18th
1652   // bit of EDX), while the EAX=0x1b leaf returns information on the
1653   // availability of specific pconfig leafs.
1654   // The target feature here only refers to the the first of these two.
1655   // Users might need to check for the availability of specific pconfig
1656   // leaves using cpuid, since that information is ignored while
1657   // detecting features using the "-march=native" flag.
1658   // For more info, see X86 ISA docs.
1659   Features["pconfig"] = HasLeaf7 && ((EDX >> 18) & 1);
1660   Features["amx-bf16"]   = HasLeaf7 && ((EDX >> 22) & 1) && HasAMXSave;
1661   Features["avx512fp16"] = HasLeaf7 && ((EDX >> 23) & 1) && HasAVX512Save;
1662   Features["amx-tile"]   = HasLeaf7 && ((EDX >> 24) & 1) && HasAMXSave;
1663   Features["amx-int8"]   = HasLeaf7 && ((EDX >> 25) & 1) && HasAMXSave;
1664   bool HasLeaf7Subleaf1 =
1665       MaxLevel >= 7 && !getX86CpuIDAndInfoEx(0x7, 0x1, &EAX, &EBX, &ECX, &EDX);
1666   Features["avxvnni"]    = HasLeaf7Subleaf1 && ((EAX >> 4) & 1) && HasAVXSave;
1667   Features["avx512bf16"] = HasLeaf7Subleaf1 && ((EAX >> 5) & 1) && HasAVX512Save;
1668   Features["hreset"]     = HasLeaf7Subleaf1 && ((EAX >> 22) & 1);
1669 
1670   bool HasLeafD = MaxLevel >= 0xd &&
1671                   !getX86CpuIDAndInfoEx(0xd, 0x1, &EAX, &EBX, &ECX, &EDX);
1672 
1673   // Only enable XSAVE if OS has enabled support for saving YMM state.
1674   Features["xsaveopt"] = HasLeafD && ((EAX >> 0) & 1) && HasAVXSave;
1675   Features["xsavec"]   = HasLeafD && ((EAX >> 1) & 1) && HasAVXSave;
1676   Features["xsaves"]   = HasLeafD && ((EAX >> 3) & 1) && HasAVXSave;
1677 
1678   bool HasLeaf14 = MaxLevel >= 0x14 &&
1679                   !getX86CpuIDAndInfoEx(0x14, 0x0, &EAX, &EBX, &ECX, &EDX);
1680 
1681   Features["ptwrite"] = HasLeaf14 && ((EBX >> 4) & 1);
1682 
1683   bool HasLeaf19 =
1684       MaxLevel >= 0x19 && !getX86CpuIDAndInfo(0x19, &EAX, &EBX, &ECX, &EDX);
1685   Features["widekl"] = HasLeaf7 && HasLeaf19 && ((EBX >> 2) & 1);
1686 
1687   return true;
1688 }
1689 #elif defined(__linux__) && (defined(__arm__) || defined(__aarch64__))
1690 bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
1691   std::unique_ptr<llvm::MemoryBuffer> P = getProcCpuinfoContent();
1692   if (!P)
1693     return false;
1694 
1695   SmallVector<StringRef, 32> Lines;
1696   P->getBuffer().split(Lines, "\n");
1697 
1698   SmallVector<StringRef, 32> CPUFeatures;
1699 
1700   // Look for the CPU features.
1701   for (unsigned I = 0, E = Lines.size(); I != E; ++I)
1702     if (Lines[I].startswith("Features")) {
1703       Lines[I].split(CPUFeatures, ' ');
1704       break;
1705     }
1706 
1707 #if defined(__aarch64__)
1708   // Keep track of which crypto features we have seen
1709   enum { CAP_AES = 0x1, CAP_PMULL = 0x2, CAP_SHA1 = 0x4, CAP_SHA2 = 0x8 };
1710   uint32_t crypto = 0;
1711 #endif
1712 
1713   for (unsigned I = 0, E = CPUFeatures.size(); I != E; ++I) {
1714     StringRef LLVMFeatureStr = StringSwitch<StringRef>(CPUFeatures[I])
1715 #if defined(__aarch64__)
1716                                    .Case("asimd", "neon")
1717                                    .Case("fp", "fp-armv8")
1718                                    .Case("crc32", "crc")
1719                                    .Case("atomics", "lse")
1720                                    .Case("sve", "sve")
1721                                    .Case("sve2", "sve2")
1722 #else
1723                                    .Case("half", "fp16")
1724                                    .Case("neon", "neon")
1725                                    .Case("vfpv3", "vfp3")
1726                                    .Case("vfpv3d16", "d16")
1727                                    .Case("vfpv4", "vfp4")
1728                                    .Case("idiva", "hwdiv-arm")
1729                                    .Case("idivt", "hwdiv")
1730 #endif
1731                                    .Default("");
1732 
1733 #if defined(__aarch64__)
1734     // We need to check crypto separately since we need all of the crypto
1735     // extensions to enable the subtarget feature
1736     if (CPUFeatures[I] == "aes")
1737       crypto |= CAP_AES;
1738     else if (CPUFeatures[I] == "pmull")
1739       crypto |= CAP_PMULL;
1740     else if (CPUFeatures[I] == "sha1")
1741       crypto |= CAP_SHA1;
1742     else if (CPUFeatures[I] == "sha2")
1743       crypto |= CAP_SHA2;
1744 #endif
1745 
1746     if (LLVMFeatureStr != "")
1747       Features[LLVMFeatureStr] = true;
1748   }
1749 
1750 #if defined(__aarch64__)
1751   // If we have all crypto bits we can add the feature
1752   if (crypto == (CAP_AES | CAP_PMULL | CAP_SHA1 | CAP_SHA2))
1753     Features["crypto"] = true;
1754 #endif
1755 
1756   return true;
1757 }
1758 #elif defined(_WIN32) && (defined(__aarch64__) || defined(_M_ARM64))
1759 bool sys::getHostCPUFeatures(StringMap<bool> &Features) {
1760   if (IsProcessorFeaturePresent(PF_ARM_NEON_INSTRUCTIONS_AVAILABLE))
1761     Features["neon"] = true;
1762   if (IsProcessorFeaturePresent(PF_ARM_V8_CRC32_INSTRUCTIONS_AVAILABLE))
1763     Features["crc"] = true;
1764   if (IsProcessorFeaturePresent(PF_ARM_V8_CRYPTO_INSTRUCTIONS_AVAILABLE))
1765     Features["crypto"] = true;
1766 
1767   return true;
1768 }
1769 #else
1770 bool sys::getHostCPUFeatures(StringMap<bool> &Features) { return false; }
1771 #endif
1772 
1773 std::string sys::getProcessTriple() {
1774   std::string TargetTripleString = updateTripleOSVersion(LLVM_HOST_TRIPLE);
1775   Triple PT(Triple::normalize(TargetTripleString));
1776 
1777   if (sizeof(void *) == 8 && PT.isArch32Bit())
1778     PT = PT.get64BitArchVariant();
1779   if (sizeof(void *) == 4 && PT.isArch64Bit())
1780     PT = PT.get32BitArchVariant();
1781 
1782   return PT.str();
1783 }
1784