Merlin’s Delphi Forge

AMD K6-2, K6-III and Athlon support 3DNow! instructions. This instruction set improves 3D and multimedia performance. But before you use these in your program you may want to check if the CPU supports 3DNow! This is the code to use:

{$ifndef ver80} // Because of 32 bit register use
  function Get3DNowSupport: Boolean; assembler;
  asm
    push  ebx
    mov   @Result, True
    mov   eax, $80000000 // Query for extended fuctions
    dw    $A20F // CPUID instruction
    cmp   eax, $80000000 // Is 800_0001h supported?
    jbe   @NOEXTENDED // If not, 3DNow! technology is not supported
    mov   eax, $80000001 // Setup extended function 8000_0001h
    dw    $A20F // CPUID instruction
    test  edx, $80000000 // Test bit 31
    jnz   @EXIT // 3DNow! technology is supported
  @NOEXTENDED:
    mov  @Result, False
  @EXIT:
    pop ebx
  end;
{$endif}

Tags: 3dnow technology, amd k6 2, asm, assembler, athlon support, boolean, cmp, cpuid instruction, dw, ebx, edx, exit pop, ifndef, instruction set, mov eax, multimedia performance