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/ADT/Triple.h"
  18 #include "llvm/Target/TargetSubtarget.h"
  19 #include "llvm/CallingConv.h"
  20 #include <string>
  21
  22 namespace llvm {
  23 class GlobalValue;
  24 class TargetMachine;
  25
  26 /// PICStyles - The X86 backend supports a number of different styles of PIC.
  27 ///
  28 namespace PICStyles {
  29 enum Style {
  30   StubPIC,          // Used on i386-darwin in -fPIC mode.
  31   StubDynamicNoPIC, // Used on i386-darwin in -mdynamic-no-pic mode.
  32   GOT,              // Used on many 32-bit unices in -fPIC mode.
  33   RIPRel,           // Used on X86-64 when not in -static mode.
  34   None              // Set when in -static mode (not PIC or DynamicNoPIC mode).
  35 };
  36 }
  37
  38 class X86Subtarget : public TargetSubtarget {
  39 protected:
  40   enum X86SSEEnum {
  41     NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
  42   };
  43
  44   enum X863DNowEnum {
  45     NoThreeDNow, ThreeDNow, ThreeDNowA
  46   };
  47
  48   /// PICStyle - Which PIC style to use
  49   ///
  50   PICStyles::Style PICStyle;
  51
  52   /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
  53   /// none supported.
  54   X86SSEEnum X86SSELevel;
  55
  56   /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
  57   ///
  58   X863DNowEnum X863DNowLevel;
  59
  60   /// HasCMov - True if this processor has conditional move instructions
  61   /// (generally pentium pro+).
  62   bool HasCMov;
  63
  64   /// HasX86_64 - True if the processor supports X86-64 instructions.
  65   ///
  66   bool HasX86_64;
  67
  68   /// HasSSE4A - True if the processor supports SSE4A instructions.
  69   bool HasSSE4A;
  70
  71   /// HasAVX - Target has AVX instructions
  72   bool HasAVX;
  73
  74   /// HasAES - Target has AES instructions
  75   bool HasAES;
  76
  77   /// HasCLMUL - Target has carry-less multiplication
  78   bool HasCLMUL;
  79
  80   /// HasFMA3 - Target has 3-operand fused multiply-add
  81   bool HasFMA3;
  82
  83   /// HasFMA4 - Target has 4-operand fused multiply-add
  84   bool HasFMA4;
  85
  86   /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
  87   bool IsBTMemSlow;
  88
  89   /// IsUAMemFast - True if unaligned memory access is fast.
  90   bool IsUAMemFast;
  91
  92   /// HasVectorUAMem - True if SIMD operations can have unaligned memory
  93   /// operands. This may require setting a feature bit in the processor.
  94   bool HasVectorUAMem;
  95
  96   /// stackAlignment - The minimum alignment known to hold of the stack frame on
  97   /// entry to the function and which must be maintained by every function.
  98   unsigned stackAlignment;
  99
 100   /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
 101   ///
 102   unsigned MaxInlineSizeThreshold;
 103
 104   /// TargetTriple - What processor and OS we're targeting.
 105   Triple TargetTriple;
 106
 107 private:
 108   /// Is64Bit - True if the processor supports 64-bit instructions and
 109   /// pointer size is 64 bit.
 110   bool Is64Bit;
 111
 112 public:
 113
 114   /// This constructor initializes the data members to match that
 115   /// of the specified triple.
 116   ///
 117   X86Subtarget(const std::string &TT, const std::string &FS, bool is64Bit);
 118
 119   /// getStackAlignment - Returns the minimum alignment known to hold of the
 120   /// stack frame on entry to the function and which must be maintained by every
 121   /// function for this subtarget.
 122   unsigned getStackAlignment() const { return stackAlignment; }
 123
 124   /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
 125   /// that still makes it profitable to inline the call.
 126   unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
 127
 128   /// ParseSubtargetFeatures - Parses features string setting specified
 129   /// subtarget options.  Definition of function is auto generated by tblgen.
 130   std::string ParseSubtargetFeatures(const std::string &FS,
 131                                      const std::string &CPU);
 132
 133   /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
 134   /// instruction.
 135   void AutoDetectSubtargetFeatures();
 136
 137   bool is64Bit() const { return Is64Bit; }
 138
 139   PICStyles::Style getPICStyle() const { return PICStyle; }
 140   void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
 141
 142   bool hasCMov() const { return HasCMov; }
 143   bool hasMMX() const { return X86SSELevel >= MMX; }
 144   bool hasSSE1() const { return X86SSELevel >= SSE1; }
 145   bool hasSSE2() const { return X86SSELevel >= SSE2; }
 146   bool hasSSE3() const { return X86SSELevel >= SSE3; }
 147   bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
 148   bool hasSSE41() const { return X86SSELevel >= SSE41; }
 149   bool hasSSE42() const { return X86SSELevel >= SSE42; }
 150   bool hasSSE4A() const { return HasSSE4A; }
 151   bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
 152   bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
 153   bool hasAVX() const { return HasAVX; }
 154   bool hasAES() const { return HasAES; }
 155   bool hasCLMUL() const { return HasCLMUL; }
 156   bool hasFMA3() const { return HasFMA3; }
 157   bool hasFMA4() const { return HasFMA4; }
 158   bool isBTMemSlow() const { return IsBTMemSlow; }
 159   bool isUnalignedMemAccessFast() const { return IsUAMemFast; }
 160   bool hasVectorUAMem() const { return HasVectorUAMem; }
 161
 162   bool isTargetDarwin() const { return TargetTriple.getOS() == Triple::Darwin; }
 163
 164   // ELF is a reasonably sane default and the only other X86 targets we
 165   // support are Darwin and Windows. Just use "not those".
 166   bool isTargetELF() const {
 167     return !isTargetDarwin() && !isTargetWindows() && !isTargetCygMing();
 168   }
 169   bool isTargetLinux() const { return TargetTriple.getOS() == Triple::Linux; }
 170
 171   bool isTargetWindows() const { return TargetTriple.getOS() == Triple::Win32; }
 172   bool isTargetMingw() const {
 173     return TargetTriple.getOS() == Triple::MinGW32 ||
 174            TargetTriple.getOS() == Triple::MinGW64; }
 175   bool isTargetCygwin() const { return TargetTriple.getOS() == Triple::Cygwin; }
 176   bool isTargetCygMing() const {
 177     return isTargetMingw() || isTargetCygwin();
 178   }
 179
 180   /// isTargetCOFF - Return true if this is any COFF/Windows target variant.
 181   bool isTargetCOFF() const {
 182     return isTargetMingw() || isTargetCygwin() || isTargetWindows();
 183   }
 184
 185   bool isTargetWin64() const {
 186     return Is64Bit && (isTargetMingw() || isTargetWindows());
 187   }
 188
 189   bool isTargetWin32() const {
 190     return !Is64Bit && (isTargetMingw() || isTargetWindows());
 191   }
 192
 193   bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
 194   bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
 195   bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
 196
 197   bool isPICStyleStubPIC() const {
 198     return PICStyle == PICStyles::StubPIC;
 199   }
 200
 201   bool isPICStyleStubNoDynamic() const {
 202     return PICStyle == PICStyles::StubDynamicNoPIC;
 203   }
 204   bool isPICStyleStubAny() const {
 205     return PICStyle == PICStyles::StubDynamicNoPIC ||
 206            PICStyle == PICStyles::StubPIC; }
 207
 208   /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
 209   /// 10 = Snow Leopard, etc.
 210   unsigned getDarwinVers() const {
 211     if (isTargetDarwin()) return TargetTriple.getDarwinMajorNumber();
 212     return 0;
 213   }
 214
 215   /// ClassifyGlobalReference - Classify a global variable reference for the
 216   /// current subtarget according to how we should reference it in a non-pcrel
 217   /// context.
 218   unsigned char ClassifyGlobalReference(const GlobalValue *GV,
 219                                         const TargetMachine &TM)const;
 220
 221   /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
 222   /// current subtarget according to how we should reference it in a non-pcrel
 223   /// context.
 224   unsigned char ClassifyBlockAddressReference() const;
 225
 226   /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
 227   /// to immediate address.
 228   bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
 229
 230   /// This function returns the name of a function which has an interface
 231   /// like the non-standard bzero function, if such a function exists on
 232   /// the current subtarget and it is considered prefereable over
 233   /// memset with zero passed as the second argument. Otherwise it
 234   /// returns null.
 235   const char *getBZeroEntry() const;
 236
 237   /// getSpecialAddressLatency - For targets where it is beneficial to
 238   /// backschedule instructions that compute addresses, return a value
 239   /// indicating the number of scheduling cycles of backscheduling that
 240   /// should be attempted.
 241   unsigned getSpecialAddressLatency() const;
 242
 243   /// IsCalleePop - Test whether a function should pop its own arguments.
 244   bool IsCalleePop(bool isVarArg, CallingConv::ID CallConv) const;
 245 };
 246
 247 } // End llvm namespace
 248
 249 #endif