Contains the capability flags of the CPU.


extern int cpu_capabilities;
Contains CPU flags indicating what features are available on the current CPU. The flags can be any combination of these:
      CPU_ID       - Indicates that the "cpuid" instruction is
		     available. If this is set, then all Allegro CPU
		     variables are 100% reliable, otherwise there
		     may be some mistakes.
      CPU_FPU      - An FPU is available.
      CPU_IA64     - Running on Intel 64 bit CPU
      CPU_AMD64    - Running on AMD 64 bit CPU
      CPU_MMX      - Intel MMX  instruction set is available.
      CPU_MMXPLUS  - Intel MMX+ instruction set is available.
      CPU_SSE      - Intel SSE  instruction set is available.
      CPU_SSE2     - Intel SSE2 instruction set is available.
      CPU_SSE3     - Intel SSE3 instruction set is available.
      CPU_3DNOW    - AMD 3DNow! instruction set is available.
      CPU_ENH3DNOW - AMD Enhanced 3DNow! instruction set is
      CPU_CMOV     - Pentium Pro "cmov" instruction is available.
You can check for multiple features by OR-ing the flags together. For example, to check if the CPU has an FPU and MMX instructions available, you'd do:
      if ((cpu_capabilities & (CPU_FPU | CPU_MMX)) ==
	  (CPU_FPU | CPU_MMX)) {
	 printf("CPU has both an FPU and MMX instructions!\n");
You can read this variable after you have called check_cpu() (which is automatically called by allegro_init()).

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