lib/Target/X86/X86Subtarget.h

   1 //=====---- X86Subtarget.h - Define Subtarget for the X86 -----*- C++ -*--====//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file declares the X86 specific subclass of TargetSubtarget.
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 #ifndef X86SUBTARGET_H
  15 #define X86SUBTARGET_H
  16
  17 #include "llvm/Target/TargetSubtarget.h"
  18 #include <string>
  19
  20 namespace llvm {
  21 class GlobalValue;
  22 class TargetMachine;
  23
  24 /// PICStyles - The X86 backend supports a number of different styles of PIC.
  25 ///
  26 namespace PICStyles {
  27 enum Style {
  28   StubPIC,          // Used on i386-darwin in -fPIC mode.
  29   StubDynamicNoPIC, // Used on i386-darwin in -mdynamic-no-pic mode.
  30   GOT,              // Used on many 32-bit unices in -fPIC mode.
  31   RIPRel,           // Used on X86-64 when not in -static mode.
  32   None              // Set when in -static mode (not PIC or DynamicNoPIC mode).
  33 };
  34 }
  35
  36 class X86Subtarget : public TargetSubtarget {
  37 protected:
  38   enum X86SSEEnum {
  39     NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
  40   };
  41
  42   enum X863DNowEnum {
  43     NoThreeDNow, ThreeDNow, ThreeDNowA
  44   };
  45
  46   /// PICStyle - Which PIC style to use
  47   ///
  48   PICStyles::Style PICStyle;
  49
  50   /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
  51   /// none supported.
  52   X86SSEEnum X86SSELevel;
  53
  54   /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
  55   ///
  56   X863DNowEnum X863DNowLevel;
  57
  58   /// HasCMov - True if this processor has conditional move instructions
  59   /// (generally pentium pro+).
  60   bool HasCMov;
  61
  62   /// HasX86_64 - True if the processor supports X86-64 instructions.
  63   ///
  64   bool HasX86_64;
  65
  66   /// HasSSE4A - True if the processor supports SSE4A instructions.
  67   bool HasSSE4A;
  68
  69   /// HasAVX - Target has AVX instructions
  70   bool HasAVX;
  71
  72   /// HasFMA3 - Target has 3-operand fused multiply-add
  73   bool HasFMA3;
  74
  75   /// HasFMA4 - Target has 4-operand fused multiply-add
  76   bool HasFMA4;
  77
  78   /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
  79   bool IsBTMemSlow;
  80
  81   /// DarwinVers - Nonzero if this is a darwin platform: the numeric
  82   /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
  83   unsigned char DarwinVers; // Is any darwin-x86 platform.
  84
  85   /// isLinux - true if this is a "linux" platform.
  86   bool IsLinux;
  87
  88   /// stackAlignment - The minimum alignment known to hold of the stack frame on
  89   /// entry to the function and which must be maintained by every function.
  90   unsigned stackAlignment;
  91
  92   /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
  93   ///
  94   unsigned MaxInlineSizeThreshold;
  95
  96 private:
  97   /// Is64Bit - True if the processor supports 64-bit instructions and
  98   /// pointer size is 64 bit.
  99   bool Is64Bit;
 100
 101 public:
 102   enum {
 103     isELF, isCygwin, isDarwin, isWindows, isMingw
 104   } TargetType;
 105
 106   /// This constructor initializes the data members to match that
 107   /// of the specified triple.
 108   ///
 109   X86Subtarget(const std::string &TT, const std::string &FS, bool is64Bit);
 110
 111   /// getStackAlignment - Returns the minimum alignment known to hold of the
 112   /// stack frame on entry to the function and which must be maintained by every
 113   /// function for this subtarget.
 114   unsigned getStackAlignment() const { return stackAlignment; }
 115
 116   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
 117   /// that still makes it profitable to inline the call.
 118   unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
 119
 120   /// ParseSubtargetFeatures - Parses features string setting specified
 121   /// subtarget options.  Definition of function is auto generated by tblgen.
 122   std::string ParseSubtargetFeatures(const std::string &FS,
 123                                      const std::string &CPU);
 124
 125   /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
 126   /// instruction.
 127   void AutoDetectSubtargetFeatures();
 128
 129   bool is64Bit() const { return Is64Bit; }
 130
 131   PICStyles::Style getPICStyle() const { return PICStyle; }
 132   void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
 133
 134   bool hasMMX() const { return X86SSELevel >= MMX; }
 135   bool hasSSE1() const { return X86SSELevel >= SSE1; }
 136   bool hasSSE2() const { return X86SSELevel >= SSE2; }
 137   bool hasSSE3() const { return X86SSELevel >= SSE3; }
 138   bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
 139   bool hasSSE41() const { return X86SSELevel >= SSE41; }
 140   bool hasSSE42() const { return X86SSELevel >= SSE42; }
 141   bool hasSSE4A() const { return HasSSE4A; }
 142   bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
 143   bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
 144   bool hasAVX() const { return HasAVX; }
 145   bool hasFMA3() const { return HasFMA3; }
 146   bool hasFMA4() const { return HasFMA4; }
 147   bool isBTMemSlow() const { return IsBTMemSlow; }
 148
 149   bool isTargetDarwin() const { return TargetType == isDarwin; }
 150   bool isTargetELF() const { return TargetType == isELF; }
 151
 152   bool isTargetWindows() const { return TargetType == isWindows; }
 153   bool isTargetMingw() const { return TargetType == isMingw; }
 154   bool isTargetCygwin() const { return TargetType == isCygwin; }
 155   bool isTargetCygMing() const {
 156     return TargetType == isMingw || TargetType == isCygwin;
 157   }
 158
 159   /// isTargetCOFF - Return true if this is any COFF/Windows target variant.
 160   bool isTargetCOFF() const {
 161     return TargetType == isMingw || TargetType == isCygwin ||
 162            TargetType == isWindows;
 163   }
 164
 165   bool isTargetWin64() const {
 166     return Is64Bit && (TargetType == isMingw || TargetType == isWindows);
 167   }
 168
 169   std::string getDataLayout() const {
 170     const char *p;
 171     if (is64Bit())
 172       p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128";
 173     else if (isTargetDarwin())
 174       p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128";
 175     else
 176       p = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32";
 177     return std::string(p);
 178   }
 179
 180   bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
 181   bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
 182   bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
 183
 184   bool isPICStyleStubPIC() const {
 185     return PICStyle == PICStyles::StubPIC;
 186   }
 187
 188   bool isPICStyleStubNoDynamic() const {
 189     return PICStyle == PICStyles::StubDynamicNoPIC;
 190   }
 191   bool isPICStyleStubAny() const {
 192     return PICStyle == PICStyles::StubDynamicNoPIC ||
 193            PICStyle == PICStyles::StubPIC; }
 194
 195   /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
 196   /// 10 = Snow Leopard, etc.
 197   unsigned getDarwinVers() const { return DarwinVers; }
 198
 199   /// isLinux - Return true if the target is "Linux".
 200   bool isLinux() const { return IsLinux; }
 201
 202
 203   /// ClassifyGlobalReference - Classify a global variable reference for the
 204   /// current subtarget according to how we should reference it in a non-pcrel
 205   /// context.
 206   unsigned char ClassifyGlobalReference(const GlobalValue *GV,
 207                                         const TargetMachine &TM)const;
 208
 209   /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
 210   /// to immediate address.
 211   bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
 212
 213   /// This function returns the name of a function which has an interface
 214   /// like the non-standard bzero function, if such a function exists on
 215   /// the current subtarget and it is considered prefereable over
 216   /// memset with zero passed as the second argument. Otherwise it
 217   /// returns null.
 218   const char *getBZeroEntry() const;
 219
 220   /// getSpecialAddressLatency - For targets where it is beneficial to
 221   /// backschedule instructions that compute addresses, return a value
 222   /// indicating the number of scheduling cycles of backscheduling that
 223   /// should be attempted.
 224   unsigned getSpecialAddressLatency() const;
 225 };
 226
 227 } // End llvm namespace
 228
 229 #endif