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. */
25 const char *host_detect_local_cpu (int argc, const char **argv);
28 #define cpuid(num,a,b,c,d) \
29 asm volatile ("xchgl %%ebx, %1; cpuid; xchgl %%ebx, %1" \
30 : "=a" (a), "=r" (b), "=c" (c), "=d" (d) \
33 #define bit_CMPXCHG8B (1 << 8)
34 #define bit_CMOV (1 << 15)
35 #define bit_MMX (1 << 23)
36 #define bit_SSE (1 << 25)
37 #define bit_SSE2 (1 << 26)
39 #define bit_SSE3 (1 << 0)
40 #define bit_CMPXCHG16B (1 << 13)
42 #define bit_3DNOW (1 << 31)
43 #define bit_3DNOWP (1 << 30)
44 #define bit_LM (1 << 29)
46 /* This will be called by the spec parser in gcc.c when it sees
47 a %:local_cpu_detect(args) construct. Currently it will be called
48 with either "arch" or "tune" as argument depending on if -march=native
49 or -mtune=native is to be substituted.
51 It returns a string containing new command line parameters to be
52 put at the place of the above two options, depending on what CPU
53 this is executed. E.g. "-march=k8" on an AMD64 machine
56 ARGC and ARGV are set depending on the actual arguments given
58 const char *host_detect_local_cpu (int argc, const char **argv)
60 const char *cpu = "i386";
61 unsigned int eax, ebx, ecx, edx;
62 unsigned int max_level;
64 unsigned int ext_level;
65 unsigned char has_mmx = 0, has_3dnow = 0, has_3dnowp = 0, has_sse = 0;
66 unsigned char has_sse2 = 0, has_sse3 = 0, has_cmov = 0;
67 unsigned char has_longmode = 0;
68 unsigned char is_amd = 0;
69 unsigned int family = 0;
71 || (strcmp (argv[0], "arch")
72 && strcmp (argv[0], "tune")))
76 /* See if we can use cpuid. */
77 asm volatile ("pushfl; pushfl; popl %0; movl %0,%1; xorl %2,%0;"
78 "pushl %0; popfl; pushfl; popl %0; popfl"
79 : "=&r" (eax), "=&r" (ebx)
82 if (((eax ^ ebx) & 0x00200000) == 0)
88 /* Check the highest input value for eax. */
89 cpuid (0, eax, ebx, ecx, edx);
91 /* We only look at the first four characters. */
96 cpuid (1, eax, ebx, ecx, edx);
97 has_cmov = !!(edx & bit_CMOV);
98 has_mmx = !!(edx & bit_MMX);
99 has_sse = !!(edx & bit_SSE);
100 has_sse2 = !!(edx & bit_SSE2);
101 has_sse3 = !!(ecx & bit_SSE3);
102 /* We don't care for extended family. */
103 family = (eax >> 8) & ~(1 << 4);
105 cpuid (0x80000000, eax, ebx, ecx, edx);
107 if (ext_level >= 0x80000000)
109 cpuid (0x80000001, eax, ebx, ecx, edx);
110 has_3dnow = !!(edx & bit_3DNOW);
111 has_3dnowp = !!(edx & bit_3DNOWP);
112 has_longmode = !!(edx & bit_LM);
115 is_amd = vendor == *(unsigned int*)"Auth";
127 if (has_sse2 || has_longmode)
144 /* It's a pentiumpro with sse2 --> pentium-m */
147 /* Would have to look at extended family, but it's at least
161 return concat ("-m", argv[0], "=", cpu, NULL);
164 /* If we aren't compiling with GCC we just provide a minimal
166 const char *host_detect_local_cpu (int argc, const char **argv)
168 return concat ("-m", argv[0], "=i386", NULL);
170 #endif /* GCC_VERSION */