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 Module;
  22 class GlobalValue;
  23 class TargetMachine;
  24
  25 /// PICStyles - The X86 backend supports a number of different styles of PIC.
  26 ///
  27 namespace PICStyles {
  28 enum Style {
  29   StubPIC,          // Used on i386-darwin in -fPIC mode.
  30   StubDynamicNoPIC, // Used on i386-darwin in -mdynamic-no-pic mode.
  31   GOT,              // Used on many 32-bit unices in -fPIC mode.
  32   RIPRel,           // Used on X86-64 when not in -static mode.
  33   None              // Set when in -static mode (not PIC or DynamicNoPIC mode).
  34 };
  35 }
  36
  37 class X86Subtarget : public TargetSubtarget {
  38 public:
  39   enum AsmWriterFlavorTy {
  40     // Note: This numbering has to match the GCC assembler dialects for inline
  41     // asm alternatives to work right.
  42     ATT = 0, Intel = 1, Unset
  43   };
  44 protected:
  45   enum X86SSEEnum {
  46     NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
  47   };
  48
  49   enum X863DNowEnum {
  50     NoThreeDNow, ThreeDNow, ThreeDNowA
  51   };
  52
  53   /// AsmFlavor - Which x86 asm dialect to use.
  54   ///
  55   AsmWriterFlavorTy AsmFlavor;
  56
  57   /// PICStyle - Which PIC style to use
  58   ///
  59   PICStyles::Style PICStyle;
  60
  61   /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
  62   /// none supported.
  63   X86SSEEnum X86SSELevel;
  64
  65   /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
  66   ///
  67   X863DNowEnum X863DNowLevel;
  68
  69   /// HasX86_64 - True if the processor supports X86-64 instructions.
  70   ///
  71   bool HasX86_64;
  72
  73   /// HasSSE4A - True if the processor supports SSE4A instructions.
  74   bool HasSSE4A;
  75
  76   /// HasAVX - Target has AVX instructions
  77   bool HasAVX;
  78
  79   /// HasFMA3 - Target has 3-operand fused multiply-add
  80   bool HasFMA3;
  81
  82   /// HasFMA4 - Target has 4-operand fused multiply-add
  83   bool HasFMA4;
  84
  85   /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
  86   bool IsBTMemSlow;
  87
  88   /// DarwinVers - Nonzero if this is a darwin platform: the numeric
  89   /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
  90   unsigned char DarwinVers; // Is any darwin-x86 platform.
  91
  92   /// isLinux - true if this is a "linux" platform.
  93   bool IsLinux;
  94
  95   /// stackAlignment - The minimum alignment known to hold of the stack frame on
  96   /// entry to the function and which must be maintained by every function.
  97   unsigned stackAlignment;
  98
  99   /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
 100   ///
 101   unsigned MaxInlineSizeThreshold;
 102
 103 private:
 104   /// Is64Bit - True if the processor supports 64-bit instructions and module
 105   /// pointer size is 64 bit.
 106   bool Is64Bit;
 107
 108 public:
 109   enum {
 110     isELF, isCygwin, isDarwin, isWindows, isMingw
 111   } TargetType;
 112
 113   /// This constructor initializes the data members to match that
 114   /// of the specified module.
 115   ///
 116   X86Subtarget(const Module &M, const std::string &FS, bool is64Bit);
 117
 118   /// getStackAlignment - Returns the minimum alignment known to hold of the
 119   /// stack frame on entry to the function and which must be maintained by every
 120   /// function for this subtarget.
 121   unsigned getStackAlignment() const { return stackAlignment; }
 122
 123   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
 124   /// that still makes it profitable to inline the call.
 125   unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
 126
 127   /// ParseSubtargetFeatures - Parses features string setting specified
 128   /// subtarget options.  Definition of function is auto generated by tblgen.
 129   std::string ParseSubtargetFeatures(const std::string &FS,
 130                                      const std::string &CPU);
 131
 132   /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
 133   /// instruction.
 134   void AutoDetectSubtargetFeatures();
 135
 136   bool is64Bit() const { return Is64Bit; }
 137
 138   PICStyles::Style getPICStyle() const { return PICStyle; }
 139   void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
 140
 141   bool hasMMX() const { return X86SSELevel >= MMX; }
 142   bool hasSSE1() const { return X86SSELevel >= SSE1; }
 143   bool hasSSE2() const { return X86SSELevel >= SSE2; }
 144   bool hasSSE3() const { return X86SSELevel >= SSE3; }
 145   bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
 146   bool hasSSE41() const { return X86SSELevel >= SSE41; }
 147   bool hasSSE42() const { return X86SSELevel >= SSE42; }
 148   bool hasSSE4A() const { return HasSSE4A; }
 149   bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
 150   bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
 151   bool hasAVX() const { return HasAVX; }
 152   bool hasFMA3() const { return HasFMA3; }
 153   bool hasFMA4() const { return HasFMA4; }
 154   bool isBTMemSlow() const { return IsBTMemSlow; }
 155
 156   unsigned getAsmFlavor() const {
 157     return AsmFlavor != Unset ? unsigned(AsmFlavor) : 0;
 158   }
 159
 160   bool isFlavorAtt() const { return AsmFlavor == ATT; }
 161   bool isFlavorIntel() const { return AsmFlavor == Intel; }
 162
 163   bool isTargetDarwin() const { return TargetType == isDarwin; }
 164   bool isTargetELF() const { return TargetType == isELF; }
 165   bool isTargetWindows() const { return TargetType == isWindows; }
 166   bool isTargetMingw() const { return TargetType == isMingw; }
 167   bool isTargetCygMing() const {
 168     return TargetType == isMingw || TargetType == isCygwin;
 169   }
 170   bool isTargetCygwin() const { return TargetType == isCygwin; }
 171   bool isTargetWin64() const {
 172     return Is64Bit && (TargetType == isMingw || TargetType == isWindows);
 173   }
 174
 175   std::string getDataLayout() const {
 176     const char *p;
 177     if (is64Bit())
 178       p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128";
 179     else if (isTargetDarwin())
 180       p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128";
 181     else
 182       p = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32";
 183     return std::string(p);
 184   }
 185
 186   bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
 187   bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
 188   bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
 189
 190   bool isPICStyleStubPIC() const {
 191     return PICStyle == PICStyles::StubPIC;
 192   }
 193
 194   bool isPICStyleStubNoDynamic() const {
 195     return PICStyle == PICStyles::StubDynamicNoPIC;
 196   }
 197   bool isPICStyleStubAny() const {
 198     return PICStyle == PICStyles::StubDynamicNoPIC ||
 199            PICStyle == PICStyles::StubPIC; }
 200
 201   /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
 202   /// 10 = Snow Leopard, etc.
 203   unsigned getDarwinVers() const { return DarwinVers; }
 204
 205   /// isLinux - Return true if the target is "Linux".
 206   bool isLinux() const { return IsLinux; }
 207
 208
 209   /// ClassifyGlobalReference - Classify a global variable reference for the
 210   /// current subtarget according to how we should reference it in a non-pcrel
 211   /// context.
 212   unsigned char ClassifyGlobalReference(const GlobalValue *GV,
 213                                         const TargetMachine &TM)const;
 214
 215   /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
 216   /// to immediate address.
 217   bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
 218
 219   /// This function returns the name of a function which has an interface
 220   /// like the non-standard bzero function, if such a function exists on
 221   /// the current subtarget and it is considered prefereable over
 222   /// memset with zero passed as the second argument. Otherwise it
 223   /// returns null.
 224   const char *getBZeroEntry() const;
 225
 226   /// getSpecialAddressLatency - For targets where it is beneficial to
 227   /// backschedule instructions that compute addresses, return a value
 228   /// indicating the number of scheduling cycles of backscheduling that
 229   /// should be attempted.
 230   unsigned getSpecialAddressLatency() const;
 231 };
 232
 233 namespace X86 {
 234   /// GetCpuIDAndInfo - Execute the specified cpuid and return the 4 values in
 235   /// the specified arguments.  If we can't run cpuid on the host, return true.
 236   bool GetCpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
 237                        unsigned *rECX, unsigned *rEDX);
 238 }
 239
 240 } // End llvm namespace
 241
 242 #endif