1 /* Subroutines for the gcc driver.
2    Copyright (C) 2006, 2007, 2008, 2010 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3, or (at your option)
9 any later version.
10 
11 GCC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14 GNU General Public License for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 #include "config.h"
21 #include "system.h"
22 #include "coretypes.h"
23 #include "tm.h"
24 
25 const char *host_detect_local_cpu (int argc, const char **argv);
26 
27 #ifdef __GNUC__
28 #include "cpuid.h"
29 
30 struct cache_desc
31 {
32   unsigned sizekb;
33   unsigned assoc;
34   unsigned line;
35 };
36 
37 /* Returns command line parameters that describe size and
38    cache line size of the processor caches.  */
39 
40 static char *
41 describe_cache (struct cache_desc level1, struct cache_desc level2)
42 {
43   char size[100], line[100], size2[100];
44 
45   /* At the moment, gcc does not use the information
46      about the associativity of the cache.  */
47 
48   snprintf (size, sizeof (size),
49 	    "--param l1-cache-size=%u ", level1.sizekb);
50   snprintf (line, sizeof (line),
51 	    "--param l1-cache-line-size=%u ", level1.line);
52 
53   snprintf (size2, sizeof (size2),
54 	    "--param l2-cache-size=%u ", level2.sizekb);
55 
56   return concat (size, line, size2, NULL);
57 }
58 
59 /* Detect L2 cache parameters using CPUID extended function 0x80000006.  */
60 
61 static void
62 detect_l2_cache (struct cache_desc *level2)
63 {
64   unsigned eax, ebx, ecx, edx;
65   unsigned assoc;
66 
67   __cpuid (0x80000006, eax, ebx, ecx, edx);
68 
69   level2->sizekb = (ecx >> 16) & 0xffff;
70   level2->line = ecx & 0xff;
71 
72   assoc = (ecx >> 12) & 0xf;
73   if (assoc == 6)
74     assoc = 8;
75   else if (assoc == 8)
76     assoc = 16;
77   else if (assoc >= 0xa && assoc <= 0xc)
78     assoc = 32 + (assoc - 0xa) * 16;
79   else if (assoc >= 0xd && assoc <= 0xe)
80     assoc = 96 + (assoc - 0xd) * 32;
81 
82   level2->assoc = assoc;
83 }
84 
85 /* Returns the description of caches for an AMD processor.  */
86 
87 static const char *
88 detect_caches_amd (unsigned max_ext_level)
89 {
90   unsigned eax, ebx, ecx, edx;
91 
92   struct cache_desc level1, level2 = {0, 0, 0};
93 
94   if (max_ext_level < 0x80000005)
95     return "";
96 
97   __cpuid (0x80000005, eax, ebx, ecx, edx);
98 
99   level1.sizekb = (ecx >> 24) & 0xff;
100   level1.assoc = (ecx >> 16) & 0xff;
101   level1.line = ecx & 0xff;
102 
103   if (max_ext_level >= 0x80000006)
104     detect_l2_cache (&level2);
105 
106   return describe_cache (level1, level2);
107 }
108 
109 /* Decodes the size, the associativity and the cache line size of
110    L1/L2 caches of an Intel processor.  Values are based on
111    "Intel Processor Identification and the CPUID Instruction"
112    [Application Note 485], revision -032, December 2007.  */
113 
114 static void
115 decode_caches_intel (unsigned reg, bool xeon_mp,
116 		     struct cache_desc *level1, struct cache_desc *level2)
117 {
118   int i;
119 
120   for (i = 24; i >= 0; i -= 8)
121     switch ((reg >> i) & 0xff)
122       {
123       case 0x0a:
124 	level1->sizekb = 8; level1->assoc = 2; level1->line = 32;
125 	break;
126       case 0x0c:
127 	level1->sizekb = 16; level1->assoc = 4; level1->line = 32;
128 	break;
129       case 0x2c:
130 	level1->sizekb = 32; level1->assoc = 8; level1->line = 64;
131 	break;
132       case 0x39:
133 	level2->sizekb = 128; level2->assoc = 4; level2->line = 64;
134 	break;
135       case 0x3a:
136 	level2->sizekb = 192; level2->assoc = 6; level2->line = 64;
137 	break;
138       case 0x3b:
139 	level2->sizekb = 128; level2->assoc = 2; level2->line = 64;
140 	break;
141       case 0x3c:
142 	level2->sizekb = 256; level2->assoc = 4; level2->line = 64;
143 	break;
144       case 0x3d:
145 	level2->sizekb = 384; level2->assoc = 6; level2->line = 64;
146 	break;
147       case 0x3e:
148 	level2->sizekb = 512; level2->assoc = 4; level2->line = 64;
149 	break;
150       case 0x41:
151 	level2->sizekb = 128; level2->assoc = 4; level2->line = 32;
152 	break;
153       case 0x42:
154 	level2->sizekb = 256; level2->assoc = 4; level2->line = 32;
155 	break;
156       case 0x43:
157 	level2->sizekb = 512; level2->assoc = 4; level2->line = 32;
158 	break;
159       case 0x44:
160 	level2->sizekb = 1024; level2->assoc = 4; level2->line = 32;
161 	break;
162       case 0x45:
163 	level2->sizekb = 2048; level2->assoc = 4; level2->line = 32;
164 	break;
165       case 0x49:
166 	if (xeon_mp)
167 	  break;
168 	level2->sizekb = 4096; level2->assoc = 16; level2->line = 64;
169 	break;
170       case 0x4e:
171 	level2->sizekb = 6144; level2->assoc = 24; level2->line = 64;
172 	break;
173       case 0x60:
174 	level1->sizekb = 16; level1->assoc = 8; level1->line = 64;
175 	break;
176       case 0x66:
177 	level1->sizekb = 8; level1->assoc = 4; level1->line = 64;
178 	break;
179       case 0x67:
180 	level1->sizekb = 16; level1->assoc = 4; level1->line = 64;
181 	break;
182       case 0x68:
183 	level1->sizekb = 32; level1->assoc = 4; level1->line = 64;
184 	break;
185       case 0x78:
186 	level2->sizekb = 1024; level2->assoc = 4; level2->line = 64;
187 	break;
188       case 0x79:
189 	level2->sizekb = 128; level2->assoc = 8; level2->line = 64;
190 	break;
191       case 0x7a:
192 	level2->sizekb = 256; level2->assoc = 8; level2->line = 64;
193 	break;
194       case 0x7b:
195 	level2->sizekb = 512; level2->assoc = 8; level2->line = 64;
196 	break;
197       case 0x7c:
198 	level2->sizekb = 1024; level2->assoc = 8; level2->line = 64;
199 	break;
200       case 0x7d:
201 	level2->sizekb = 2048; level2->assoc = 8; level2->line = 64;
202 	break;
203       case 0x7f:
204 	level2->sizekb = 512; level2->assoc = 2; level2->line = 64;
205 	break;
206       case 0x82:
207 	level2->sizekb = 256; level2->assoc = 8; level2->line = 32;
208 	break;
209       case 0x83:
210 	level2->sizekb = 512; level2->assoc = 8; level2->line = 32;
211 	break;
212       case 0x84:
213 	level2->sizekb = 1024; level2->assoc = 8; level2->line = 32;
214 	break;
215       case 0x85:
216 	level2->sizekb = 2048; level2->assoc = 8; level2->line = 32;
217 	break;
218       case 0x86:
219 	level2->sizekb = 512; level2->assoc = 4; level2->line = 64;
220 	break;
221       case 0x87:
222 	level2->sizekb = 1024; level2->assoc = 8; level2->line = 64;
223 
224       default:
225 	break;
226       }
227 }
228 
229 /* Detect cache parameters using CPUID function 2.  */
230 
231 static void
232 detect_caches_cpuid2 (bool xeon_mp,
233 		      struct cache_desc *level1, struct cache_desc *level2)
234 {
235   unsigned regs[4];
236   int nreps, i;
237 
238   __cpuid (2, regs[0], regs[1], regs[2], regs[3]);
239 
240   nreps = regs[0] & 0x0f;
241   regs[0] &= ~0x0f;
242 
243   while (--nreps >= 0)
244     {
245       for (i = 0; i < 4; i++)
246 	if (regs[i] && !((regs[i] >> 31) & 1))
247 	  decode_caches_intel (regs[i], xeon_mp, level1, level2);
248 
249       if (nreps)
250 	__cpuid (2, regs[0], regs[1], regs[2], regs[3]);
251     }
252 }
253 
254 /* Detect cache parameters using CPUID function 4. This
255    method doesn't require hardcoded tables.  */
256 
257 enum cache_type
258 {
259   CACHE_END = 0,
260   CACHE_DATA = 1,
261   CACHE_INST = 2,
262   CACHE_UNIFIED = 3
263 };
264 
265 static void
266 detect_caches_cpuid4 (struct cache_desc *level1, struct cache_desc *level2,
267 		      struct cache_desc *level3)
268 {
269   struct cache_desc *cache;
270 
271   unsigned eax, ebx, ecx, edx;
272   int count;
273 
274   for (count = 0;; count++)
275     {
276       __cpuid_count(4, count, eax, ebx, ecx, edx);
277       switch (eax & 0x1f)
278 	{
279 	case CACHE_END:
280 	  return;
281 	case CACHE_DATA:
282 	case CACHE_UNIFIED:
283 	  {
284 	    switch ((eax >> 5) & 0x07)
285 	      {
286 	      case 1:
287 		cache = level1;
288 		break;
289 	      case 2:
290 		cache = level2;
291 		break;
292 	      case 3:
293 		cache = level3;
294 		break;
295 	      default:
296 		cache = NULL;
297 	      }
298 
299 	    if (cache)
300 	      {
301 		unsigned sets = ecx + 1;
302 		unsigned part = ((ebx >> 12) & 0x03ff) + 1;
303 
304 		cache->assoc = ((ebx >> 22) & 0x03ff) + 1;
305 		cache->line = (ebx & 0x0fff) + 1;
306 
307 		cache->sizekb = (cache->assoc * part
308 				 * cache->line * sets) / 1024;
309 	      }
310 	  }
311 	default:
312 	  break;
313 	}
314     }
315 }
316 
317 /* Returns the description of caches for an Intel processor.  */
318 
319 static const char *
320 detect_caches_intel (bool xeon_mp, unsigned max_level,
321 		     unsigned max_ext_level, unsigned *l2sizekb)
322 {
323   struct cache_desc level1 = {0, 0, 0}, level2 = {0, 0, 0}, level3 = {0, 0, 0};
324 
325   if (max_level >= 4)
326     detect_caches_cpuid4 (&level1, &level2, &level3);
327   else if (max_level >= 2)
328     detect_caches_cpuid2 (xeon_mp, &level1, &level2);
329   else
330     return "";
331 
332   if (level1.sizekb == 0)
333     return "";
334 
335   /* Let the L3 replace the L2. This assumes inclusive caches
336      and single threaded program for now. */
337   if (level3.sizekb)
338     level2 = level3;
339 
340   /* Intel CPUs are equipped with AMD style L2 cache info.  Try this
341      method if other methods fail to provide L2 cache parameters.  */
342   if (level2.sizekb == 0 && max_ext_level >= 0x80000006)
343     detect_l2_cache (&level2);
344 
345   *l2sizekb = level2.sizekb;
346 
347   return describe_cache (level1, level2);
348 }
349 
350 enum vendor_signatures
351 {
352   SIG_INTEL =	0x756e6547 /* Genu */,
353   SIG_AMD =	0x68747541 /* Auth */
354 };
355 
356 enum processor_signatures
357 {
358   SIG_GEODE =	0x646f6547 /* Geod */
359 };
360 
361 /* This will be called by the spec parser in gcc.c when it sees
362    a %:local_cpu_detect(args) construct.  Currently it will be called
363    with either "arch" or "tune" as argument depending on if -march=native
364    or -mtune=native is to be substituted.
365 
366    It returns a string containing new command line parameters to be
367    put at the place of the above two options, depending on what CPU
368    this is executed.  E.g. "-march=k8" on an AMD64 machine
369    for -march=native.
370 
371    ARGC and ARGV are set depending on the actual arguments given
372    in the spec.  */
373 
374 const char *host_detect_local_cpu (int argc, const char **argv)
375 {
376   enum processor_type processor = PROCESSOR_I386;
377   const char *cpu = "i386";
378 
379   const char *cache = "";
380   const char *options = "";
381 
382   unsigned int eax, ebx, ecx, edx;
383 
384   unsigned int max_level, ext_level;
385 
386   unsigned int vendor;
387   unsigned int model, family;
388 
389   unsigned int has_sse3, has_ssse3, has_cmpxchg16b;
390   unsigned int has_cmpxchg8b, has_cmov, has_mmx, has_sse, has_sse2;
391 
392   /* Extended features */
393   unsigned int has_lahf_lm = 0, has_sse4a = 0;
394   unsigned int has_longmode = 0, has_3dnowp = 0, has_3dnow = 0;
395   unsigned int has_movbe = 0, has_sse4_1 = 0, has_sse4_2 = 0;
396   unsigned int has_popcnt = 0, has_aes = 0, has_avx = 0, has_avx2 = 0;
397   unsigned int has_pclmul = 0, has_abm = 0, has_lwp = 0;
398   unsigned int has_fma = 0, has_fma4 = 0, has_xop = 0;
399   unsigned int has_bmi = 0, has_bmi2 = 0, has_tbm = 0, has_lzcnt = 0;
400   unsigned int has_rdrnd = 0, has_f16c = 0, has_fsgsbase = 0;
401 
402   bool arch;
403 
404   unsigned int l2sizekb = 0;
405 
406   if (argc < 1)
407     return NULL;
408 
409   arch = !strcmp (argv[0], "arch");
410 
411   if (!arch && strcmp (argv[0], "tune"))
412     return NULL;
413 
414   max_level = __get_cpuid_max (0, &vendor);
415   if (max_level < 1)
416     goto done;
417 
418   __cpuid (1, eax, ebx, ecx, edx);
419 
420   model = (eax >> 4) & 0x0f;
421   family = (eax >> 8) & 0x0f;
422   if (vendor == SIG_INTEL)
423     {
424       unsigned int extended_model, extended_family;
425 
426       extended_model = (eax >> 12) & 0xf0;
427       extended_family = (eax >> 20) & 0xff;
428       if (family == 0x0f)
429 	{
430 	  family += extended_family;
431 	  model += extended_model;
432 	}
433       else if (family == 0x06)
434 	model += extended_model;
435     }
436 
437   has_sse3 = ecx & bit_SSE3;
438   has_ssse3 = ecx & bit_SSSE3;
439   has_sse4_1 = ecx & bit_SSE4_1;
440   has_sse4_2 = ecx & bit_SSE4_2;
441   has_avx = ecx & bit_AVX;
442   has_cmpxchg16b = ecx & bit_CMPXCHG16B;
443   has_movbe = ecx & bit_MOVBE;
444   has_popcnt = ecx & bit_POPCNT;
445   has_aes = ecx & bit_AES;
446   has_pclmul = ecx & bit_PCLMUL;
447   has_fma = ecx & bit_FMA;
448   has_f16c = ecx & bit_F16C;
449   has_rdrnd = ecx & bit_RDRND;
450 
451   has_cmpxchg8b = edx & bit_CMPXCHG8B;
452   has_cmov = edx & bit_CMOV;
453   has_mmx = edx & bit_MMX;
454   has_sse = edx & bit_SSE;
455   has_sse2 = edx & bit_SSE2;
456 
457   if (max_level >= 7)
458     {
459       __cpuid_count (7, 0, eax, ebx, ecx, edx);
460 
461       has_bmi = ebx & bit_BMI;
462       has_avx2 = ebx & bit_AVX2;
463       has_bmi2 = ebx & bit_BMI2;
464       has_fsgsbase = ebx & bit_FSGSBASE;
465     }
466 
467   /* Check cpuid level of extended features.  */
468   __cpuid (0x80000000, ext_level, ebx, ecx, edx);
469 
470   if (ext_level > 0x80000000)
471     {
472       __cpuid (0x80000001, eax, ebx, ecx, edx);
473 
474       has_lahf_lm = ecx & bit_LAHF_LM;
475       has_sse4a = ecx & bit_SSE4a;
476       has_abm = ecx & bit_ABM;
477       has_lwp = ecx & bit_LWP;
478       has_fma4 = ecx & bit_FMA4;
479       has_xop = ecx & bit_XOP;
480       has_tbm = ecx & bit_TBM;
481       has_lzcnt = ecx & bit_LZCNT;
482 
483       has_longmode = edx & bit_LM;
484       has_3dnowp = edx & bit_3DNOWP;
485       has_3dnow = edx & bit_3DNOW;
486     }
487 
488   if (!arch)
489     {
490       if (vendor == SIG_AMD)
491 	cache = detect_caches_amd (ext_level);
492       else if (vendor == SIG_INTEL)
493 	{
494 	  bool xeon_mp = (family == 15 && model == 6);
495 	  cache = detect_caches_intel (xeon_mp, max_level,
496 				       ext_level, &l2sizekb);
497 	}
498     }
499 
500   if (vendor == SIG_AMD)
501     {
502       unsigned int name;
503 
504       /* Detect geode processor by its processor signature.  */
505       if (ext_level > 0x80000001)
506 	__cpuid (0x80000002, name, ebx, ecx, edx);
507       else
508 	name = 0;
509 
510       if (name == SIG_GEODE)
511 	processor = PROCESSOR_GEODE;
512       else if (has_bmi)
513         processor = PROCESSOR_BDVER2;
514       else if (has_xop)
515 	processor = PROCESSOR_BDVER1;
516       else if (has_sse4a && has_ssse3)
517         processor = PROCESSOR_BTVER1;
518       else if (has_sse4a)
519 	processor = PROCESSOR_AMDFAM10;
520       else if (has_sse2 || has_longmode)
521 	processor = PROCESSOR_K8;
522       else if (has_3dnowp && family == 6)
523 	processor = PROCESSOR_ATHLON;
524       else if (has_mmx)
525 	processor = PROCESSOR_K6;
526       else
527 	processor = PROCESSOR_PENTIUM;
528     }
529   else
530     {
531       switch (family)
532 	{
533 	case 4:
534 	  processor = PROCESSOR_I486;
535 	  break;
536 	case 5:
537 	  processor = PROCESSOR_PENTIUM;
538 	  break;
539 	case 6:
540 	  processor = PROCESSOR_PENTIUMPRO;
541 	  break;
542 	case 15:
543 	  processor = PROCESSOR_PENTIUM4;
544 	  break;
545 	default:
546 	  /* We have no idea.  */
547 	  processor = PROCESSOR_GENERIC32;
548 	}
549     }
550 
551   switch (processor)
552     {
553     case PROCESSOR_I386:
554       /* Default.  */
555       break;
556     case PROCESSOR_I486:
557       cpu = "i486";
558       break;
559     case PROCESSOR_PENTIUM:
560       if (arch && has_mmx)
561 	cpu = "pentium-mmx";
562       else
563 	cpu = "pentium";
564       break;
565     case PROCESSOR_PENTIUMPRO:
566       switch (model)
567 	{
568 	case 0x1c:
569 	case 0x26:
570 	  /* Atom.  */
571 	  cpu = "atom";
572 	  break;
573 	case 0x1a:
574 	case 0x1e:
575 	case 0x1f:
576 	case 0x2e:
577 	  /* Nehalem.  */
578 	  cpu = "corei7";
579 	  break;
580 	case 0x25:
581 	case 0x2c:
582 	case 0x2f:
583 	  /* Westmere.  */
584 	  cpu = "corei7";
585 	  break;
586 	case 0x2a:
587 	case 0x2d:
588 	  /* Sandy Bridge.  */
589 	  cpu = "corei7-avx";
590 	  break;
591 	case 0x17:
592 	case 0x1d:
593 	  /* Penryn.  */
594 	  cpu = "core2";
595 	  break;
596 	case 0x0f:
597 	  /* Merom.  */
598 	  cpu = "core2";
599 	  break;
600 	default:
601 	  if (arch)
602 	    {
603 	      /* This is unknown family 0x6 CPU.  */
604 	      if (has_avx)
605 		/* Assume Sandy Bridge.  */
606 		cpu = "corei7-avx";
607 	      else if (has_sse4_2)
608 		/* Assume Core i7.  */
609 		cpu = "corei7";
610 	      else if (has_ssse3)
611 		{
612 		  if (has_movbe)
613 		    /* Assume Atom.  */
614 		    cpu = "atom";
615 		  else
616 		    /* Assume Core 2.  */
617 		    cpu = "core2";
618 		}
619 	      else if (has_sse3)
620 		/* It is Core Duo.  */
621 		cpu = "pentium-m";
622 	      else if (has_sse2)
623 		/* It is Pentium M.  */
624 		cpu = "pentium-m";
625 	      else if (has_sse)
626 		/* It is Pentium III.  */
627 		cpu = "pentium3";
628 	      else if (has_mmx)
629 		/* It is Pentium II.  */
630 		cpu = "pentium2";
631 	      else
632 		/* Default to Pentium Pro.  */
633 		cpu = "pentiumpro";
634 	    }
635 	  else
636 	    /* For -mtune, we default to -mtune=generic.  */
637 	    cpu = "generic";
638 	  break;
639 	}
640       break;
641     case PROCESSOR_PENTIUM4:
642       if (has_sse3)
643 	{
644 	  if (has_longmode)
645 	    cpu = "nocona";
646 	  else
647 	    cpu = "prescott";
648 	}
649       else
650 	cpu = "pentium4";
651       break;
652     case PROCESSOR_GEODE:
653       cpu = "geode";
654       break;
655     case PROCESSOR_K6:
656       if (arch && has_3dnow)
657 	cpu = "k6-3";
658       else
659 	cpu = "k6";
660       break;
661     case PROCESSOR_ATHLON:
662       if (arch && has_sse)
663 	cpu = "athlon-4";
664       else
665 	cpu = "athlon";
666       break;
667     case PROCESSOR_K8:
668       if (arch && has_sse3)
669 	cpu = "k8-sse3";
670       else
671 	cpu = "k8";
672       break;
673     case PROCESSOR_AMDFAM10:
674       cpu = "amdfam10";
675       break;
676     case PROCESSOR_BDVER1:
677       cpu = "bdver1";
678       break;
679     case PROCESSOR_BDVER2:
680       cpu = "bdver2";
681       break;
682     case PROCESSOR_BTVER1:
683       cpu = "btver1";
684       break;
685 
686     default:
687       /* Use something reasonable.  */
688       if (arch)
689 	{
690 	  if (has_ssse3)
691 	    cpu = "core2";
692 	  else if (has_sse3)
693 	    {
694 	      if (has_longmode)
695 		cpu = "nocona";
696 	      else
697 		cpu = "prescott";
698 	    }
699 	  else if (has_sse2)
700 	    cpu = "pentium4";
701 	  else if (has_cmov)
702 	    cpu = "pentiumpro";
703 	  else if (has_mmx)
704 	    cpu = "pentium-mmx";
705 	  else if (has_cmpxchg8b)
706 	    cpu = "pentium";
707 	}
708       else
709 	cpu = "generic";
710     }
711 
712   if (arch)
713     {
714       const char *cx16 = has_cmpxchg16b ? " -mcx16" : " -mno-cx16";
715       const char *sahf = has_lahf_lm ? " -msahf" : " -mno-sahf";
716       const char *movbe = has_movbe ? " -mmovbe" : " -mno-movbe";
717       const char *ase = has_aes ? " -maes" : " -mno-aes";
718       const char *pclmul = has_pclmul ? " -mpclmul" : " -mno-pclmul";
719       const char *popcnt = has_popcnt ? " -mpopcnt" : " -mno-popcnt";
720       const char *abm = has_abm ? " -mabm" : " -mno-abm";
721       const char *lwp = has_lwp ? " -mlwp" : " -mno-lwp";
722       const char *fma = has_fma ? " -mfma" : " -mno-fma";
723       const char *fma4 = has_fma4 ? " -mfma4" : " -mno-fma4";
724       const char *xop = has_xop ? " -mxop" : " -mno-xop";
725       const char *bmi = has_bmi ? " -mbmi" : " -mno-bmi";
726       const char *bmi2 = has_bmi2 ? " -mbmi2" : " -mno-bmi2";
727       const char *tbm = has_tbm ? " -mtbm" : " -mno-tbm";
728       const char *avx = has_avx ? " -mavx" : " -mno-avx";
729       const char *avx2 = has_avx2 ? " -mavx2" : " -mno-avx2";
730       const char *sse4_2 = has_sse4_2 ? " -msse4.2" : " -mno-sse4.2";
731       const char *sse4_1 = has_sse4_1 ? " -msse4.1" : " -mno-sse4.1";
732       const char *lzcnt = has_lzcnt ? " -mlzcnt" : " -mno-lzcnt";
733       const char *rdrnd = has_rdrnd ? " -mrdrnd" : " -mno-rdrnd";
734       const char *f16c = has_f16c ? " -mf16c" : " -mno-f16c";
735       const char *fsgsbase = has_fsgsbase ? " -mfsgsbase" : " -mno-fsgsbase";
736 
737       options = concat (options, cx16, sahf, movbe, ase, pclmul,
738 			popcnt, abm, lwp, fma, fma4, xop, bmi, bmi2,
739 			tbm, avx, avx2, sse4_2, sse4_1, lzcnt, rdrnd,
740 			f16c, fsgsbase, NULL);
741     }
742 
743 done:
744   return concat (cache, "-m", argv[0], "=", cpu, options, NULL);
745 }
746 #else
747 
748 /* If we aren't compiling with GCC then the driver will just ignore
749    -march and -mtune "native" target and will leave to the newly
750    built compiler to generate code for its default target.  */
751 
752 const char *host_detect_local_cpu (int argc ATTRIBUTE_UNUSED,
753 				   const char **argv ATTRIBUTE_UNUSED)
754 {
755   return NULL;
756 }
757 #endif /* __GNUC__ */
758