1 /* Subroutines for the gcc driver.
2 Copyright (C) 2006 Free Software Foundation, Inc.
4 This file is part of GCC.
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 2, or (at your option)
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.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING. If not, write to
18 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
19 Boston, MA 02110-1301, USA. */
23 #include "coretypes.h"
27 const char *host_detect_local_cpu (int argc, const char **argv);
30 #define cpuid(num,a,b,c,d) \
31 asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1" \
32 : "=a" (a), "=r" (b), "=c" (c), "=d" (d) \
35 #define bit_CMPXCHG8B (1 << 8)
36 #define bit_CMOV (1 << 15)
37 #define bit_MMX (1 << 23)
38 #define bit_SSE (1 << 25)
39 #define bit_SSE2 (1 << 26)
41 #define bit_SSE3 (1 << 0)
42 #define bit_CMPXCHG16B (1 << 13)
44 #define bit_3DNOW (1 << 31)
45 #define bit_3DNOWP (1 << 30)
46 #define bit_LM (1 << 29)
48 /* This will be called by the spec parser in gcc.c when it sees
49 a %:local_cpu_detect(args) construct. Currently it will be called
50 with either "arch" or "tune" as argument depending on if -march=native
51 or -mtune=native is to be substituted.
53 It returns a string containing new command line parameters to be
54 put at the place of the above two options, depending on what CPU
55 this is executed. E.g. "-march=k8" on an AMD64 machine
58 ARGC and ARGV are set depending on the actual arguments given
60 const char *host_detect_local_cpu (int argc, const char **argv)
62 const char *cpu = NULL;
63 enum processor_type processor = PROCESSOR_I386;
64 unsigned int eax, ebx, ecx, edx;
65 unsigned int max_level;
67 unsigned int ext_level;
68 unsigned char has_mmx = 0, has_3dnow = 0, has_3dnowp = 0, has_sse = 0;
69 unsigned char has_sse2 = 0, has_sse3 = 0, has_cmov = 0;
70 unsigned char has_longmode = 0, has_cmpxchg8b = 0;
71 unsigned char is_amd = 0;
72 unsigned int family = 0;
78 arch = strcmp (argv[0], "arch") == 0;
79 if (!arch && strcmp (argv[0], "tune"))
83 /* See if we can use cpuid. */
84 asm volatile ("pushfl; pushfl; popl %0; movl %0,%1; xorl %2,%0;"
85 "pushl %0; popfl; pushfl; popl %0; popfl"
86 : "=&r" (eax), "=&r" (ebx)
89 if (((eax ^ ebx) & 0x00200000) == 0)
93 processor = PROCESSOR_PENTIUM;
95 /* Check the highest input value for eax. */
96 cpuid (0, eax, ebx, ecx, edx);
98 /* We only look at the first four characters. */
103 cpuid (1, eax, ebx, ecx, edx);
104 has_cmpxchg8b = !!(edx & bit_CMPXCHG8B);
105 has_cmov = !!(edx & bit_CMOV);
106 has_mmx = !!(edx & bit_MMX);
107 has_sse = !!(edx & bit_SSE);
108 has_sse2 = !!(edx & bit_SSE2);
109 has_sse3 = !!(ecx & bit_SSE3);
110 /* We don't care for extended family. */
111 family = (eax >> 8) & ~(1 << 4);
113 cpuid (0x80000000, eax, ebx, ecx, edx);
115 if (ext_level >= 0x80000000)
117 cpuid (0x80000001, eax, ebx, ecx, edx);
118 has_3dnow = !!(edx & bit_3DNOW);
119 has_3dnowp = !!(edx & bit_3DNOWP);
120 has_longmode = !!(edx & bit_LM);
123 is_amd = vendor == *(unsigned int*)"Auth";
128 processor = PROCESSOR_K6;
130 processor = PROCESSOR_ATHLON;
131 if (has_sse2 || has_longmode)
132 processor = PROCESSOR_K8;
139 /* Default is PROCESSOR_PENTIUM. */
142 processor = PROCESSOR_PENTIUMPRO;
145 processor = PROCESSOR_PENTIUM4;
148 /* We have no idea. Use something reasonable. */
164 else if (has_cmpxchg8b)
184 case PROCESSOR_PENTIUM:
190 case PROCESSOR_PENTIUMPRO:
197 /* It is Core 2 Duo. */
202 /* It is Core Duo. */
208 /* It is Pentium M. */
213 /* It is Pentium III. */
218 /* It is Pentium II. */
223 /* Default to Pentium Pro. */
229 /* For -mtune, we default to -mtune=generic. */
239 case PROCESSOR_ATHLON:
245 case PROCESSOR_PENTIUM4:
259 case PROCESSOR_NOCONA:
262 case PROCESSOR_GENERIC32:
263 case PROCESSOR_GENERIC64:
272 return concat ("-m", argv[0], "=", cpu, NULL);
275 /* If we aren't compiling with GCC we just provide a minimal
277 const char *host_detect_local_cpu (int argc, const char **argv)
285 arch = strcmp (argv[0], "arch") == 0;
286 if (!arch && strcmp (argv[0], "tune"))
291 /* FIXME: i386 is wrong for 64bit compiler. How can we tell if
292 we are generating 64bit or 32bit code? */
298 return concat ("-m", argv[0], "=", cpu, NULL);
300 #endif /* GCC_VERSION */