vpx_ports/x86.h

   1 /*
   2  *  Copyright (c) 2010 The WebM project authors. All Rights Reserved.
   3  *
   4  *  Use of this source code is governed by a BSD-style license
   5  *  that can be found in the LICENSE file in the root of the source
   6  *  tree. An additional intellectual property rights grant can be found
   7  *  in the file PATENTS.  All contributing project authors may
   8  *  be found in the AUTHORS file in the root of the source tree.
   9  */
  10
  11
  12 #ifndef VPX_PORTS_X86_H
  13 #define VPX_PORTS_X86_H
  14 #include <stdlib.h>
  15 #include "config.h"
  16
  17 typedef enum
  18 {
  19     VPX_CPU_UNKNOWN = -1,
  20     VPX_CPU_AMD,
  21     VPX_CPU_AMD_OLD,
  22     VPX_CPU_CENTAUR,
  23     VPX_CPU_CYRIX,
  24     VPX_CPU_INTEL,
  25     VPX_CPU_NEXGEN,
  26     VPX_CPU_NSC,
  27     VPX_CPU_RISE,
  28     VPX_CPU_SIS,
  29     VPX_CPU_TRANSMETA,
  30     VPX_CPU_TRANSMETA_OLD,
  31     VPX_CPU_UMC,
  32     VPX_CPU_VIA,
  33
  34     VPX_CPU_LAST
  35 }  vpx_cpu_t;
  36
  37 #if defined(__GNUC__) && __GNUC__
  38 #if ARCH_X86_64
  39 #define cpuid(func,ax,bx,cx,dx)\
  40     __asm__ __volatile__ (\
  41                           "cpuid           \n\t" \
  42                           : "=a" (ax), "=b" (bx), "=c" (cx), "=d" (dx) \
  43                           : "a"  (func));
  44 #else
  45 #define cpuid(func,ax,bx,cx,dx)\
  46     __asm__ __volatile__ (\
  47                           "mov %%ebx, %%edi   \n\t" \
  48                           "cpuid              \n\t" \
  49                           "xchg %%edi, %%ebx  \n\t" \
  50                           : "=a" (ax), "=D" (bx), "=c" (cx), "=d" (dx) \
  51                           : "a" (func));
  52 #endif
  53 #else
  54 #if ARCH_X86_64
  55 void __cpuid(int CPUInfo[4], int info_type);
  56 #pragma intrinsic(__cpuid)
  57 #define cpuid(func,a,b,c,d) do{\
  58         int regs[4];\
  59         __cpuid(regs,func); a=regs[0];  b=regs[1];  c=regs[2];  d=regs[3];\
  60     } while(0)
  61 #else
  62 #define cpuid(func,a,b,c,d)\
  63     __asm mov eax, func\
  64     __asm cpuid\
  65     __asm mov a, eax\
  66     __asm mov b, ebx\
  67     __asm mov c, ecx\
  68     __asm mov d, edx
  69 #endif
  70 #endif
  71
  72 #define HAS_MMX   0x01
  73 #define HAS_SSE   0x02
  74 #define HAS_SSE2  0x04
  75 #define HAS_SSE3  0x08
  76 #define HAS_SSSE3 0x10
  77 #define HAS_SSE4_1 0x20
  78 #ifndef BIT
  79 #define BIT(n) (1<<n)
  80 #endif
  81
  82 static int
  83 x86_simd_caps(void)
  84 {
  85     unsigned int flags = 0;
  86     unsigned int mask = ~0;
  87     unsigned int reg_eax, reg_ebx, reg_ecx, reg_edx;
  88     char *env;
  89     (void)reg_ebx;
  90
  91     /* See if the CPU capabilities are being overridden by the environment */
  92     env = getenv("VPX_SIMD_CAPS");
  93
  94     if (env && *env)
  95         return (int)strtol(env, NULL, 0);
  96
  97     env = getenv("VPX_SIMD_CAPS_MASK");
  98
  99     if (env && *env)
 100         mask = strtol(env, NULL, 0);
 101
 102     /* Ensure that the CPUID instruction supports extended features */
 103     cpuid(0, reg_eax, reg_ebx, reg_ecx, reg_edx);
 104
 105     if (reg_eax < 1)
 106         return 0;
 107
 108     /* Get the standard feature flags */
 109     cpuid(1, reg_eax, reg_ebx, reg_ecx, reg_edx);
 110
 111     if (reg_edx & BIT(23)) flags |= HAS_MMX;
 112
 113     if (reg_edx & BIT(25)) flags |= HAS_SSE; /* aka xmm */
 114
 115     if (reg_edx & BIT(26)) flags |= HAS_SSE2; /* aka wmt */
 116
 117     if (reg_ecx & BIT(0))  flags |= HAS_SSE3;
 118
 119     if (reg_ecx & BIT(9))  flags |= HAS_SSSE3;
 120
 121     if (reg_ecx & BIT(19)) flags |= HAS_SSE4_1;
 122
 123     return flags & mask;
 124 }
 125
 126 vpx_cpu_t vpx_x86_vendor(void);
 127
 128 #if ARCH_X86_64 && defined(_MSC_VER)
 129 unsigned __int64 __rdtsc(void);
 130 #pragma intrinsic(__rdtsc)
 131 #endif
 132 static unsigned int
 133 x86_readtsc(void)
 134 {
 135 #if defined(__GNUC__) && __GNUC__
 136     unsigned int tsc;
 137     __asm__ __volatile__("rdtsc\n\t":"=a"(tsc):);
 138     return tsc;
 139 #else
 140 #if ARCH_X86_64
 141     return __rdtsc();
 142 #else
 143     __asm  rdtsc;
 144 #endif
 145 #endif
 146 }
 147
 148
 149 #if defined(__GNUC__) && __GNUC__
 150 #define x86_pause_hint()\
 151     __asm__ __volatile__ ("pause \n\t")
 152 #else
 153 #if ARCH_X86_64
 154 /* No pause intrinsic for windows x64 */
 155 #define x86_pause_hint()
 156 #else
 157 #define x86_pause_hint()\
 158     __asm pause
 159 #endif
 160 #endif
 161
 162 #if defined(__GNUC__) && __GNUC__
 163 static void
 164 x87_set_control_word(unsigned short mode)
 165 {
 166     __asm__ __volatile__("fldcw %0" : : "m"(*&mode));
 167 }
 168 static unsigned short
 169 x87_get_control_word(void)
 170 {
 171     unsigned short mode;
 172     __asm__ __volatile__("fstcw %0\n\t":"=m"(*&mode):);
 173     return mode;
 174 }
 175 #elif ARCH_X86_64
 176 /* No fldcw intrinsics on Windows x64, punt to external asm */
 177 extern void           vpx_winx64_fldcw(unsigned short mode);
 178 extern unsigned short vpx_winx64_fstcw(void);
 179 #define x87_set_control_word vpx_winx64_fldcw
 180 #define x87_get_control_word vpx_winx64_fstcw
 181 #else
 182 static void
 183 x87_set_control_word(unsigned short mode)
 184 {
 185     __asm { fldcw mode }
 186 }
 187 static unsigned short
 188 x87_get_control_word(void)
 189 {
 190     unsigned short mode;
 191     __asm { fstcw mode }
 192     return mode;
 193 }
 194 #endif
 195
 196 static unsigned short
 197 x87_set_double_precision(void)
 198 {
 199     unsigned short mode = x87_get_control_word();
 200     x87_set_control_word((mode&~0x300) | 0x200);
 201     return mode;
 202 }
 203
 204
 205 extern void vpx_reset_mmx_state(void);
 206 #endif
 207