如果一台计算机支持Delphi32中的SSE2，如何探测它？

Question

c++的方法是here (在Windows下)。

而Linux下的same answer则使用GCC。

据我所知，摘录了相关的asm代码：

mov     eax, 1
cpuid
mov     features, edx

我在巴斯姆不太舒服。

我的问题：

我需要按以下方式包装测试

function IsSSE2: Boolean;
begin
  try
    Result := False;
    //
    // Some BASM code here
    //
  except
    Result := False;
  end;
end;

请帮帮我。

Answer 1

没有汇编程序，你也可以做到这一点。不过，只适用于Windows和更新版本。

function IsProcessorFeaturePresent(ProcessorFeature: DWORD): BOOL; stdcall;
  external kernel32 name 'IsProcessorFeaturePresent';

const
  PF_XMMI64_INSTRUCTIONS_AVAILABLE = 10;

function HasSSE2: boolean;
begin
  result := IsProcessorFeaturePresent(PF_XMMI64_INSTRUCTIONS_AVAILABLE);
end;

Answer 2

我认为这样做是可行的：

function SupportsSSE2: LongBool;
const
  CPUID_INTEL_SSE2 = $04000000;
asm
  push ebx
  mov eax, 1
  cpuid
  mov eax, FALSE
  test edx, CPUID_INTEL_SSE2
  jz @END
  mov eax, TRUE
@END:
  pop ebx
end;

Answer 3

下面是graphics32库用于检测处理器特性的代码：

{$IFDEF WIN64}
  {$DEFINE TARGET_x64}
{$ENDIF}

type
  TCPUInstructionSet = (ciMMX, ciEMMX, ciSSE, ciSSE2, ci3DNow, ci3DNowExt);

const
  CPUISChecks: Array[TCPUInstructionSet] of Cardinal =
    ($800000,  $400000, $2000000, $4000000, $80000000, $40000000);
    {ciMMX  ,  ciEMMX,  ciSSE   , ciSSE2  , ci3DNow ,  ci3DNowExt}

function CPUID_Available: Boolean;
asm
{$IFDEF TARGET_x64}
        MOV       EDX,False
        PUSHFQ
        POP       RAX
        MOV       ECX,EAX
        XOR       EAX,$00200000
        PUSH      RAX
        POPFQ
        PUSHFQ
        POP       RAX
        XOR       ECX,EAX
        JZ        @1
        MOV       EDX,True
@1:     PUSH      RAX
        POPFQ
        MOV       EAX,EDX
{$ELSE}
        MOV       EDX,False
        PUSHFD
        POP       EAX
        MOV       ECX,EAX
        XOR       EAX,$00200000
        PUSH      EAX
        POPFD
        PUSHFD
        POP       EAX
        XOR       ECX,EAX
        JZ        @1
        MOV       EDX,True
@1:     PUSH      EAX
        POPFD
        MOV       EAX,EDX
{$ENDIF}
end;

function CPU_Signature: Integer;
asm
{$IFDEF TARGET_x64}
        PUSH      RBX
        MOV       EAX,1
        CPUID
        POP       RBX
{$ELSE}
        PUSH      EBX
        MOV       EAX,1
        {$IFDEF FPC}
        CPUID
        {$ELSE}
        DW        $A20F   // CPUID
        {$ENDIF}
        POP       EBX
{$ENDIF}
end;

function CPU_Features: Integer;
asm
{$IFDEF TARGET_x64}
        PUSH      RBX
        MOV       EAX,1
        CPUID
        POP       RBX
        MOV       EAX,EDX
{$ELSE}
        PUSH      EBX
        MOV       EAX,1
        {$IFDEF FPC}
        CPUID
        {$ELSE}
        DW        $A20F   // CPUID
        {$ENDIF}
        POP       EBX
        MOV       EAX,EDX
{$ENDIF}
end;

function CPU_ExtensionsAvailable: Boolean;
asm
{$IFDEF TARGET_x64}
        PUSH      RBX
        MOV       @Result, True
        MOV       EAX, $80000000
        CPUID
        CMP       EAX, $80000000
        JBE       @NOEXTENSION
        JMP       @EXIT
        @NOEXTENSION:
        MOV       @Result, False
        @EXIT:
        POP       RBX
{$ELSE}
        PUSH      EBX
        MOV       @Result, True
        MOV       EAX, $80000000
        {$IFDEF FPC}
        CPUID
        {$ELSE}
        DW        $A20F   // CPUID
        {$ENDIF}
        CMP       EAX, $80000000
        JBE       @NOEXTENSION
        JMP       @EXIT
      @NOEXTENSION:
        MOV       @Result, False
      @EXIT:
        POP       EBX
{$ENDIF}
end;

function CPU_ExtFeatures: Integer;
asm
{$IFDEF TARGET_x64}
        PUSH      RBX
        MOV       EAX, $80000001
        CPUID
        POP       RBX
        MOV       EAX,EDX
{$ELSE}
        PUSH      EBX
        MOV       EAX, $80000001
        {$IFDEF FPC}
        CPUID
        {$ELSE}
        DW        $A20F   // CPUID
        {$ENDIF}
        POP       EBX
        MOV       EAX,EDX
{$ENDIF}
end;

function HasInstructionSet(const InstructionSet: TCPUInstructionSet): Boolean;
// Must be implemented for each target CPU on which specific functions rely
begin
  Result := False;
  if not CPUID_Available then Exit;                   // no CPUID available
  if CPU_Signature shr 8 and $0F < 5 then Exit;       // not a Pentium class

  case InstructionSet of
    ci3DNow, ci3DNowExt:
      {$IFNDEF FPC}
      if not CPU_ExtensionsAvailable or (CPU_ExtFeatures and CPUISChecks[InstructionSet] = 0) then
      {$ENDIF}
        Exit;
    ciEMMX:
      begin
        // check for SSE, necessary for Intel CPUs because they don't implement the
        // extended info
        if (CPU_Features and CPUISChecks[ciSSE] = 0) and
          (not CPU_ExtensionsAvailable or (CPU_ExtFeatures and CPUISChecks[ciEMMX] = 0)) then
          Exit;
      end;
  else
    if CPU_Features and CPUISChecks[InstructionSet] = 0 then
      Exit; // return -> instruction set not supported
    end;

  Result := True;
end;

你可以打电话给HasInstructionSet(ciSSE2)来发现你需要的东西。