crypto/x86cpuid.pl

   1 #!/usr/bin/env perl
   2
   3 push(@INC,"perlasm");
   4 require "x86asm.pl";
   5
   6 &asm_init($ARGV[0],"x86cpuid");
   7
   8 for (@ARGV) { $sse2=1 if (/-DOPENSSL_IA32_SSE2/); }
   9
  10 &function_begin("OPENSSL_ia32_cpuid");
  11         &xor    ("edx","edx");
  12         &pushf  ();
  13         &pop    ("eax");
  14         &mov    ("ecx","eax");
  15         &xor    ("eax",1<<21);
  16         &push   ("eax");
  17         &popf   ();
  18         &pushf  ();
  19         &pop    ("eax");
  20         &xor    ("ecx","eax");
  21         &bt     ("ecx",21);
  22         &jnc    (&label("done"));
  23         &xor    ("eax","eax");
  24         &cpuid  ();
  25         &xor    ("eax","eax");
  26         &cmp    ("ebx",0x756e6547);     # "Genu"
  27         &setne  (&LB("eax"));
  28         &mov    ("ebp","eax");
  29         &cmp    ("edx",0x49656e69);     # "ineI"
  30         &setne  (&LB("eax"));
  31         &or     ("ebp","eax");
  32         &cmp    ("ecx",0x6c65746e);     # "ntel"
  33         &setne  (&LB("eax"));
  34         &or     ("ebp","eax");
  35         &mov    ("eax",1);
  36         &cpuid  ();
  37         &cmp    ("ebp",0);
  38         &jne    (&label("notP4"));
  39         &and    (&HB("eax"),15);        # familiy ID
  40         &cmp    (&HB("eax"),15);        # P4?
  41         &jne    (&label("notP4"));
  42         &or     ("edx",1<<20);          # use reserved bit to engage RC4_CHAR
  43 &set_label("notP4");
  44         &bt     ("edx",28);             # test hyper-threading bit
  45         &jnc    (&label("done"));
  46         &shr    ("ebx",16);
  47         &cmp    (&LB("ebx"),1);         # see if cache is shared(*)
  48         &ja     (&label("done"));
  49         &and    ("edx",0xefffffff);     # clear hyper-threading bit if not
  50 &set_label("done");
  51         &mov    ("eax","edx");
  52         &mov    ("edx","ecx");
  53 &function_end("OPENSSL_ia32_cpuid");
  54 # (*)   on Core2 this value is set to 2 denoting the fact that L2
  55 #       cache is shared between cores.
  56
  57 &external_label("OPENSSL_ia32cap_P");
  58
  59 &function_begin_B("OPENSSL_rdtsc","EXTRN\t_OPENSSL_ia32cap_P:DWORD");
  60         &xor    ("eax","eax");
  61         &xor    ("edx","edx");
  62         &picmeup("ecx","OPENSSL_ia32cap_P");
  63         &bt     (&DWP(0,"ecx"),4);
  64         &jnc    (&label("notsc"));
  65         &rdtsc  ();
  66 &set_label("notsc");
  67         &ret    ();
  68 &function_end_B("OPENSSL_rdtsc");
  69
  70 # This works in Ring 0 only [read DJGPP+MS-DOS+privileged DPMI host],
  71 # but it's safe to call it on any [supported] 32-bit platform...
  72 # Just check for [non-]zero return value...
  73 &function_begin_B("OPENSSL_instrument_halt","EXTRN\t_OPENSSL_ia32cap_P:DWORD");
  74         &picmeup("ecx","OPENSSL_ia32cap_P");
  75         &bt     (&DWP(0,"ecx"),4);
  76         &jnc    (&label("nohalt"));     # no TSC
  77
  78         &data_word(0x9058900e);         # push %cs; pop %eax
  79         &and    ("eax",3);
  80         &jnz    (&label("nohalt"));     # not enough privileges
  81
  82         &pushf  ();
  83         &pop    ("eax")
  84         &bt     ("eax",9);
  85         &jnc    (&label("nohalt"));     # interrupts are disabled
  86
  87         &rdtsc  ();
  88         &push   ("edx");
  89         &push   ("eax");
  90         &halt   ();
  91         &rdtsc  ();
  92
  93         &sub    ("eax",&DWP(0,"esp"));
  94         &sbb    ("edx",&DWP(4,"esp"));
  95         &add    ("esp",8);
  96         &ret    ();
  97
  98 &set_label("nohalt");
  99         &xor    ("eax","eax");
 100         &xor    ("edx","edx");
 101         &ret    ();
 102 &function_end_B("OPENSSL_instrument_halt");
 103
 104 # Essentially there is only one use for this function. Under DJGPP:
 105 #
 106 #       #include <go32.h>
 107 #       ...
 108 #       i=OPENSSL_far_spin(_dos_ds,0x46c);
 109 #       ...
 110 # to obtain the number of spins till closest timer interrupt.
 111
 112 &function_begin_B("OPENSSL_far_spin");
 113         &pushf  ();
 114         &pop    ("eax")
 115         &bt     ("eax",9);
 116         &jnc    (&label("nospin"));     # interrupts are disabled
 117
 118         &mov    ("eax",&DWP(4,"esp"));
 119         &mov    ("ecx",&DWP(8,"esp"));
 120         &data_word (0x90d88e1e);        # push %ds, mov %eax,%ds
 121         &xor    ("eax","eax");
 122         &mov    ("edx",&DWP(0,"ecx"));
 123         &jmp    (&label("spin"));
 124
 125         &align  (16);
 126 &set_label("spin");
 127         &inc    ("eax");
 128         &cmp    ("edx",&DWP(0,"ecx"));
 129         &je     (&label("spin"));
 130
 131         &data_word (0x1f909090);        # pop   %ds
 132         &ret    ();
 133
 134 &set_label("nospin");
 135         &xor    ("eax","eax");
 136         &xor    ("edx","edx");
 137         &ret    ();
 138 &function_end_B("OPENSSL_far_spin");
 139
 140 &function_begin_B("OPENSSL_wipe_cpu","EXTRN\t_OPENSSL_ia32cap_P:DWORD");
 141         &xor    ("eax","eax");
 142         &xor    ("edx","edx");
 143         &picmeup("ecx","OPENSSL_ia32cap_P");
 144         &mov    ("ecx",&DWP(0,"ecx"));
 145         &bt     (&DWP(0,"ecx"),1);
 146         &jnc    (&label("no_x87"));
 147         if ($sse2) {
 148                 &bt     (&DWP(0,"ecx"),26);
 149                 &jnc    (&label("no_sse2"));
 150                 &pxor   ("xmm0","xmm0");
 151                 &pxor   ("xmm1","xmm1");
 152                 &pxor   ("xmm2","xmm2");
 153                 &pxor   ("xmm3","xmm3");
 154                 &pxor   ("xmm4","xmm4");
 155                 &pxor   ("xmm5","xmm5");
 156                 &pxor   ("xmm6","xmm6");
 157                 &pxor   ("xmm7","xmm7");
 158         &set_label("no_sse2");
 159         }
 160         # just a bunch of fldz to zap the fp/mm bank followed by finit...
 161         &data_word(0xeed9eed9,0xeed9eed9,0xeed9eed9,0xeed9eed9,0x90e3db9b);
 162 &set_label("no_x87");
 163         &lea    ("eax",&DWP(4,"esp"));
 164         &ret    ();
 165 &function_end_B("OPENSSL_wipe_cpu");
 166
 167 &function_begin_B("OPENSSL_atomic_add");
 168         &mov    ("edx",&DWP(4,"esp"));  # fetch the pointer, 1st arg
 169         &mov    ("ecx",&DWP(8,"esp"));  # fetch the increment, 2nd arg
 170         &push   ("ebx");
 171         &nop    ();
 172         &mov    ("eax",&DWP(0,"edx"));
 173 &set_label("spin");
 174         &lea    ("ebx",&DWP(0,"eax","ecx"));
 175         &nop    ();
 176         &data_word(0x1ab10ff0); # lock; cmpxchg %ebx,(%edx)     # %eax is envolved and is always reloaded
 177         &jne    (&label("spin"));
 178         &mov    ("eax","ebx");  # OpenSSL expects the new value
 179         &pop    ("ebx");
 180         &ret    ();
 181 &function_end_B("OPENSSL_atomic_add");
 182
 183 # This function can become handy under Win32 in situations when
 184 # we don't know which calling convention, __stdcall or __cdecl(*),
 185 # indirect callee is using. In C it can be deployed as
 186 #
 187 #ifdef OPENSSL_CPUID_OBJ
 188 #       type OPENSSL_indirect_call(void *f,...);
 189 #       ...
 190 #       OPENSSL_indirect_call(func,[up to $max arguments]);
 191 #endif
 192 #
 193 # (*)   it's designed to work even for __fastcall if number of
 194 #       arguments is 1 or 2!
 195 &function_begin_B("OPENSSL_indirect_call");
 196         {
 197         my $i,$max=7;           # $max has to be chosen as 4*n-1
 198                                 # in order to preserve eventual
 199                                 # stack alignment
 200         &push   ("ebp");
 201         &mov    ("ebp","esp");
 202         &sub    ("esp",$max*4);
 203         &mov    ("ecx",&DWP(12,"ebp"));
 204         &mov    (&DWP(0,"esp"),"ecx");
 205         &mov    ("edx",&DWP(16,"ebp"));
 206         &mov    (&DWP(4,"esp"),"edx");
 207         for($i=2;$i<$max;$i++)
 208                 {
 209                 # Some copies will be redundant/bogus...
 210                 &mov    ("eax",&DWP(12+$i*4,"ebp"));
 211                 &mov    (&DWP(0+$i*4,"esp"),"eax");
 212                 }
 213         &call_ptr       (&DWP(8,"ebp"));# make the call...
 214         &mov    ("esp","ebp");  # ... and just restore the stack pointer
 215                                 # without paying attention to what we called,
 216                                 # (__cdecl *func) or (__stdcall *one).
 217         &pop    ("ebp");
 218         &ret    ();
 219         }
 220 &function_end_B("OPENSSL_indirect_call");
 221
 222 &function_begin_B("OPENSSL_cleanse");
 223         &mov    ("edx",&wparam(0));
 224         &mov    ("ecx",&wparam(1));
 225         &xor    ("eax","eax");
 226         &cmp    ("ecx",7);
 227         &jae    (&label("lot"));
 228 &set_label("little");
 229         &mov    (&BP(0,"edx"),"al");
 230         &sub    ("ecx",1);
 231         &lea    ("edx",&DWP(1,"edx"));
 232         &jnz    (&label("little"));
 233         &ret    ();
 234
 235 &set_label("lot",16);
 236         &test   ("edx",3);
 237         &jz     (&label("aligned"));
 238         &mov    (&BP(0,"edx"),"al");
 239         &lea    ("ecx",&DWP(-1,"ecx"));
 240         &lea    ("edx",&DWP(1,"edx"));
 241         &jmp    (&label("lot"));
 242 &set_label("aligned");
 243         &mov    (&DWP(0,"edx"),"eax");
 244         &lea    ("ecx",&DWP(-4,"ecx"));
 245         &test   ("ecx",-4);
 246         &lea    ("edx",&DWP(4,"edx"));
 247         &jnz    (&label("aligned"));
 248         &cmp    ("ecx",0);
 249         &jne    (&label("little"));
 250         &ret    ();
 251 &function_end_B("OPENSSL_cleanse");
 252
 253 &initseg("OPENSSL_cpuid_setup");
 254
 255 &asm_finish();