crypto/armcap.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <string.h>
   4 #include <setjmp.h>
   5 #include <signal.h>
   6 #include <crypto.h>
   7
   8 #include "arm_arch.h"
   9
  10 unsigned int OPENSSL_armcap_P;
  11
  12 static sigset_t all_masked;
  13
  14 static sigjmp_buf ill_jmp;
  15 static void ill_handler (int sig) { siglongjmp(ill_jmp,sig); }
  16
  17 /*
  18  * Following subroutines could have been inlined, but it's not all
  19  * ARM compilers support inline assembler...
  20  */
  21 void _armv7_neon_probe(void);
  22 unsigned int _armv7_tick(void);
  23
  24 unsigned int OPENSSL_rdtsc(void)
  25         {
  26         if (OPENSSL_armcap_P & ARMV7_TICK)
  27                 return _armv7_tick();
  28         else
  29                 return 0;
  30         }
  31
  32 #if defined(__GNUC__) && __GNUC__>=2
  33 void OPENSSL_cpuid_setup(void) __attribute__((constructor));
  34 #endif
  35 void OPENSSL_cpuid_setup(void)
  36         {
  37         char *e;
  38         struct sigaction        ill_oact,ill_act;
  39         sigset_t                oset;
  40         static int trigger=0;
  41
  42         if (trigger) return;
  43         trigger=1;
  44
  45         if ((e=getenv("OPENSSL_armcap")))
  46                 {
  47                 OPENSSL_armcap_P=strtoul(e,NULL,0);
  48                 return;
  49                 }
  50
  51         sigfillset(&all_masked);
  52         sigdelset(&all_masked,SIGILL);
  53         sigdelset(&all_masked,SIGTRAP);
  54         sigdelset(&all_masked,SIGFPE);
  55         sigdelset(&all_masked,SIGBUS);
  56         sigdelset(&all_masked,SIGSEGV);
  57
  58         OPENSSL_armcap_P = 0;
  59
  60         memset(&ill_act,0,sizeof(ill_act));
  61         ill_act.sa_handler = ill_handler;
  62         ill_act.sa_mask    = all_masked;
  63
  64         sigprocmask(SIG_SETMASK,&ill_act.sa_mask,&oset);
  65         sigaction(SIGILL,&ill_act,&ill_oact);
  66
  67         if (sigsetjmp(ill_jmp,1) == 0)
  68                 {
  69                 _armv7_neon_probe();
  70                 OPENSSL_armcap_P |= ARMV7_NEON;
  71                 }
  72         if (sigsetjmp(ill_jmp,1) == 0)
  73                 {
  74                 _armv7_tick();
  75                 OPENSSL_armcap_P |= ARMV7_TICK;
  76                 }
  77
  78         sigaction (SIGILL,&ill_oact,NULL);
  79         sigprocmask(SIG_SETMASK,&oset,NULL);
  80         }