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 public:
  38   enum AsmWriterFlavorTy {
  39     // Note: This numbering has to match the GCC assembler dialects for inline
  40     // asm alternatives to work right.
  41     ATT = 0, Intel = 1, Unset
  42   };
  43 protected:
  44   enum X86SSEEnum {
  45     NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
  46   };
  47
  48   enum X863DNowEnum {
  49     NoThreeDNow, ThreeDNow, ThreeDNowA
  50   };
  51
  52   /// AsmFlavor - Which x86 asm dialect to use.
  53   ///
  54   AsmWriterFlavorTy AsmFlavor;
  55
  56   /// PICStyle - Which PIC style to use
  57   ///
  58   PICStyles::Style PICStyle;
  59
  60   /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
  61   /// none supported.
  62   X86SSEEnum X86SSELevel;
  63
  64   /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
  65   ///
  66   X863DNowEnum X863DNowLevel;
  67
  68   /// HasX86_64 - True if the processor supports X86-64 instructions.
  69   ///
  70   bool HasX86_64;
  71
  72   /// HasSSE4A - True if the processor supports SSE4A instructions.
  73   bool HasSSE4A;
  74
  75   /// HasAVX - Target has AVX instructions
  76   bool HasAVX;
  77
  78   /// HasFMA3 - Target has 3-operand fused multiply-add
  79   bool HasFMA3;
  80
  81   /// HasFMA4 - Target has 4-operand fused multiply-add
  82   bool HasFMA4;
  83
  84   /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
  85   bool IsBTMemSlow;
  86
  87   /// DarwinVers - Nonzero if this is a darwin platform: the numeric
  88   /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
  89   unsigned char DarwinVers; // Is any darwin-x86 platform.
  90
  91   /// isLinux - true if this is a "linux" platform.
  92   bool IsLinux;
  93
  94   /// stackAlignment - The minimum alignment known to hold of the stack frame on
  95   /// entry to the function and which must be maintained by every function.
  96   unsigned stackAlignment;
  97
  98   /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
  99   ///
 100   unsigned MaxInlineSizeThreshold;
 101
 102 private:
 103   /// Is64Bit - True if the processor supports 64-bit instructions and
 104   /// pointer size is 64 bit.
 105   bool Is64Bit;
 106
 107 public:
 108   enum {
 109     isELF, isCygwin, isDarwin, isWindows, isMingw
 110   } TargetType;
 111
 112   /// This constructor initializes the data members to match that
 113   /// of the specified triple.
 114   ///
 115   X86Subtarget(const std::string &TT, const std::string &FS, bool is64Bit);
 116
 117   /// getStackAlignment - Returns the minimum alignment known to hold of the
 118   /// stack frame on entry to the function and which must be maintained by every
 119   /// function for this subtarget.
 120   unsigned getStackAlignment() const { return stackAlignment; }
 121
 122   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
 123   /// that still makes it profitable to inline the call.
 124   unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
 125
 126   /// ParseSubtargetFeatures - Parses features string setting specified
 127   /// subtarget options.  Definition of function is auto generated by tblgen.
 128   std::string ParseSubtargetFeatures(const std::string &FS,
 129                                      const std::string &CPU);
 130
 131   /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
 132   /// instruction.
 133   void AutoDetectSubtargetFeatures();
 134
 135   bool is64Bit() const { return Is64Bit; }
 136
 137   PICStyles::Style getPICStyle() const { return PICStyle; }
 138   void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
 139
 140   bool hasMMX() const { return X86SSELevel >= MMX; }
 141   bool hasSSE1() const { return X86SSELevel >= SSE1; }
 142   bool hasSSE2() const { return X86SSELevel >= SSE2; }
 143   bool hasSSE3() const { return X86SSELevel >= SSE3; }
 144   bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
 145   bool hasSSE41() const { return X86SSELevel >= SSE41; }
 146   bool hasSSE42() const { return X86SSELevel >= SSE42; }
 147   bool hasSSE4A() const { return HasSSE4A; }
 148   bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
 149   bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
 150   bool hasAVX() const { return HasAVX; }
 151   bool hasFMA3() const { return HasFMA3; }
 152   bool hasFMA4() const { return HasFMA4; }
 153   bool isBTMemSlow() const { return IsBTMemSlow; }
 154
 155   unsigned getAsmFlavor() const {
 156     return AsmFlavor != Unset ? unsigned(AsmFlavor) : 0;
 157   }
 158
 159   bool isFlavorAtt() const { return AsmFlavor == ATT; }
 160   bool isFlavorIntel() const { return AsmFlavor == Intel; }
 161
 162   bool isTargetDarwin() const { return TargetType == isDarwin; }
 163   bool isTargetELF() const { return TargetType == isELF; }
 164   bool isTargetWindows() const { return TargetType == isWindows; }
 165   bool isTargetMingw() const { return TargetType == isMingw; }
 166   bool isTargetCygMing() const {
 167     return TargetType == isMingw || TargetType == isCygwin;
 168   }
 169   bool isTargetCygwin() const { return TargetType == isCygwin; }
 170   bool isTargetWin64() const {
 171     return Is64Bit && (TargetType == isMingw || TargetType == isWindows);
 172   }
 173
 174   std::string getDataLayout() const {
 175     const char *p;
 176     if (is64Bit())
 177       p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128";
 178     else if (isTargetDarwin())
 179       p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128";
 180     else
 181       p = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32";
 182     return std::string(p);
 183   }
 184
 185   bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
 186   bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
 187   bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
 188
 189   bool isPICStyleStubPIC() const {
 190     return PICStyle == PICStyles::StubPIC;
 191   }
 192
 193   bool isPICStyleStubNoDynamic() const {
 194     return PICStyle == PICStyles::StubDynamicNoPIC;
 195   }
 196   bool isPICStyleStubAny() const {
 197     return PICStyle == PICStyles::StubDynamicNoPIC ||
 198            PICStyle == PICStyles::StubPIC; }
 199
 200   /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
 201   /// 10 = Snow Leopard, etc.
 202   unsigned getDarwinVers() const { return DarwinVers; }
 203
 204   /// isLinux - Return true if the target is "Linux".
 205   bool isLinux() const { return IsLinux; }
 206
 207
 208   /// ClassifyGlobalReference - Classify a global variable reference for the
 209   /// current subtarget according to how we should reference it in a non-pcrel
 210   /// context.
 211   unsigned char ClassifyGlobalReference(const GlobalValue *GV,
 212                                         const TargetMachine &TM)const;
 213
 214   /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
 215   /// to immediate address.
 216   bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
 217
 218   /// This function returns the name of a function which has an interface
 219   /// like the non-standard bzero function, if such a function exists on
 220   /// the current subtarget and it is considered prefereable over
 221   /// memset with zero passed as the second argument. Otherwise it
 222   /// returns null.
 223   const char *getBZeroEntry() const;
 224
 225   /// getSpecialAddressLatency - For targets where it is beneficial to
 226   /// backschedule instructions that compute addresses, return a value
 227   /// indicating the number of scheduling cycles of backscheduling that
 228   /// should be attempted.
 229   unsigned getSpecialAddressLatency() const;
 230 };
 231
 232 namespace X86 {
 233   /// GetCpuIDAndInfo - Execute the specified cpuid and return the 4 values in
 234   /// the specified arguments.  If we can't run cpuid on the host, return true.
 235   bool GetCpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
 236                        unsigned *rECX, unsigned *rEDX);
 237 }
 238
 239 } // End llvm namespace
 240
 241 #endif