X86Subtarget.h revision 0e292376d09223d791ed2ccc8935e98cbd36f1f8 
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 TargetSubtargetInfo.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef X86SUBTARGET_H
15#define X86SUBTARGET_H
16
17#include "llvm/CallingConv.h"
18#include "llvm/ADT/Triple.h"
19#include "llvm/Target/TargetSubtargetInfo.h"
20#include <string>
21
22#define GET_SUBTARGETINFO_HEADER
23#include "X86GenSubtargetInfo.inc"
24
25namespace llvm {
26class GlobalValue;
27class StringRef;
28class TargetMachine;
29
30/// PICStyles - The X86 backend supports a number of different styles of PIC.
31///
32namespace PICStyles {
33enum Style {
34  StubPIC,          // Used on i386-darwin in -fPIC mode.
35  StubDynamicNoPIC, // Used on i386-darwin in -mdynamic-no-pic mode.
36  GOT,              // Used on many 32-bit unices in -fPIC mode.
37  RIPRel,           // Used on X86-64 when not in -static mode.
38  None              // Set when in -static mode (not PIC or DynamicNoPIC mode).
39};
40}
41
42class X86Subtarget : public X86GenSubtargetInfo {
43protected:
44  enum X86SSEEnum {
45    NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, AVX, AVX2
46  };
47
48  enum X863DNowEnum {
49    NoThreeDNow, ThreeDNow, ThreeDNowA
50  };
51
52  enum X86ProcFamilyEnum {
53    Others, IntelAtom
54  };
55
56  /// X86ProcFamily - X86 processor family: Intel Atom, and others
57  X86ProcFamilyEnum X86ProcFamily;
58
59  /// PICStyle - Which PIC style to use
60  ///
61  PICStyles::Style PICStyle;
62
63  /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
64  /// none supported.
65  X86SSEEnum X86SSELevel;
66
67  /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
68  ///
69  X863DNowEnum X863DNowLevel;
70
71  /// HasCMov - True if this processor has conditional move instructions
72  /// (generally pentium pro+).
73  bool HasCMov;
74
75  /// HasX86_64 - True if the processor supports X86-64 instructions.
76  ///
77  bool HasX86_64;
78
79  /// HasPOPCNT - True if the processor supports POPCNT.
80  bool HasPOPCNT;
81
82  /// HasSSE4A - True if the processor supports SSE4A instructions.
83  bool HasSSE4A;
84
85  /// HasAES - Target has AES instructions
86  bool HasAES;
87
88  /// HasPCLMUL - Target has carry-less multiplication
89  bool HasPCLMUL;
90
91  /// HasFMA - Target has 3-operand fused multiply-add
92  bool HasFMA;
93
94  /// HasFMA4 - Target has 4-operand fused multiply-add
95  bool HasFMA4;
96
97  /// HasXOP - Target has XOP instructions
98  bool HasXOP;
99
100  /// HasMOVBE - True if the processor has the MOVBE instruction.
101  bool HasMOVBE;
102
103  /// HasRDRAND - True if the processor has the RDRAND instruction.
104  bool HasRDRAND;
105
106  /// HasF16C - Processor has 16-bit floating point conversion instructions.
107  bool HasF16C;
108
109  /// HasFSGSBase - Processor has FS/GS base insturctions.
110  bool HasFSGSBase;
111
112  /// HasLZCNT - Processor has LZCNT instruction.
113  bool HasLZCNT;
114
115  /// HasBMI - Processor has BMI1 instructions.
116  bool HasBMI;
117
118  /// HasBMI2 - Processor has BMI2 instructions.
119  bool HasBMI2;
120
121  /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
122  bool IsBTMemSlow;
123
124  /// IsUAMemFast - True if unaligned memory access is fast.
125  bool IsUAMemFast;
126
127  /// HasVectorUAMem - True if SIMD operations can have unaligned memory
128  /// operands. This may require setting a feature bit in the processor.
129  bool HasVectorUAMem;
130
131  /// HasCmpxchg16b - True if this processor has the CMPXCHG16B instruction;
132  /// this is true for most x86-64 chips, but not the first AMD chips.
133  bool HasCmpxchg16b;
134
135  /// UseLeaForSP - True if the LEA instruction should be used for adjusting
136  /// the stack pointer. This is an optimization for Intel Atom processors.
137  bool UseLeaForSP;
138
139  /// PostRAScheduler - True if using post-register-allocation scheduler.
140  bool PostRAScheduler;
141
142  /// stackAlignment - The minimum alignment known to hold of the stack frame on
143  /// entry to the function and which must be maintained by every function.
144  unsigned stackAlignment;
145
146  /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
147  ///
148  unsigned MaxInlineSizeThreshold;
149
150  /// TargetTriple - What processor and OS we're targeting.
151  Triple TargetTriple;
152
153  /// Instruction itineraries for scheduling
154  InstrItineraryData InstrItins;
155
156private:
157  /// In64BitMode - True if compiling for 64-bit, false for 32-bit.
158  bool In64BitMode;
159
160public:
161
162  /// This constructor initializes the data members to match that
163  /// of the specified triple.
164  ///
165  X86Subtarget(const std::string &TT, const std::string &CPU,
166               const std::string &FS,
167               unsigned StackAlignOverride, bool is64Bit);
168
169  /// getStackAlignment - Returns the minimum alignment known to hold of the
170  /// stack frame on entry to the function and which must be maintained by every
171  /// function for this subtarget.
172  unsigned getStackAlignment() const { return stackAlignment; }
173
174  /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
175  /// that still makes it profitable to inline the call.
176  unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
177
178  /// ParseSubtargetFeatures - Parses features string setting specified
179  /// subtarget options.  Definition of function is auto generated by tblgen.
180  void ParseSubtargetFeatures(StringRef CPU, StringRef FS);
181
182  /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
183  /// instruction.
184  void AutoDetectSubtargetFeatures();
185
186  bool is64Bit() const { return In64BitMode; }
187
188  PICStyles::Style getPICStyle() const { return PICStyle; }
189  void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
190
191  bool hasCMov() const { return HasCMov; }
192  bool hasMMX() const { return X86SSELevel >= MMX; }
193  bool hasSSE1() const { return X86SSELevel >= SSE1; }
194  bool hasSSE2() const { return X86SSELevel >= SSE2; }
195  bool hasSSE3() const { return X86SSELevel >= SSE3; }
196  bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
197  bool hasSSE41() const { return X86SSELevel >= SSE41; }
198  bool hasSSE42() const { return X86SSELevel >= SSE42; }
199  bool hasAVX() const { return X86SSELevel >= AVX; }
200  bool hasAVX2() const { return X86SSELevel >= AVX2; }
201  bool hasSSE4A() const { return HasSSE4A; }
202  bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
203  bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
204  bool hasPOPCNT() const { return HasPOPCNT; }
205  bool hasAES() const { return HasAES; }
206  bool hasPCLMUL() const { return HasPCLMUL; }
207  bool hasFMA() const { return HasFMA; }
208  // FIXME: Favor FMA when both are enabled. Is this the right thing to do?
209  bool hasFMA4() const { return HasFMA4 && !HasFMA; }
210  bool hasXOP() const { return HasXOP; }
211  bool hasMOVBE() const { return HasMOVBE; }
212  bool hasRDRAND() const { return HasRDRAND; }
213  bool hasF16C() const { return HasF16C; }
214  bool hasFSGSBase() const { return HasFSGSBase; }
215  bool hasLZCNT() const { return HasLZCNT; }
216  bool hasBMI() const { return HasBMI; }
217  bool hasBMI2() const { return HasBMI2; }
218  bool isBTMemSlow() const { return IsBTMemSlow; }
219  bool isUnalignedMemAccessFast() const { return IsUAMemFast; }
220  bool hasVectorUAMem() const { return HasVectorUAMem; }
221  bool hasCmpxchg16b() const { return HasCmpxchg16b; }
222  bool useLeaForSP() const { return UseLeaForSP; }
223
224  bool isAtom() const { return X86ProcFamily == IntelAtom; }
225
226  const Triple &getTargetTriple() const { return TargetTriple; }
227
228  bool isTargetDarwin() const { return TargetTriple.isOSDarwin(); }
229  bool isTargetFreeBSD() const {
230    return TargetTriple.getOS() == Triple::FreeBSD;
231  }
232  bool isTargetSolaris() const {
233    return TargetTriple.getOS() == Triple::Solaris;
234  }
235
236  // ELF is a reasonably sane default and the only other X86 targets we
237  // support are Darwin and Windows. Just use "not those".
238  bool isTargetELF() const { return TargetTriple.isOSBinFormatELF(); }
239  bool isTargetLinux() const { return TargetTriple.getOS() == Triple::Linux; }
240  bool isTargetNaCl() const {
241    return TargetTriple.getOS() == Triple::NativeClient;
242  }
243  bool isTargetNaCl32() const { return isTargetNaCl() && !is64Bit(); }
244  bool isTargetNaCl64() const { return isTargetNaCl() && is64Bit(); }
245  bool isTargetWindows() const { return TargetTriple.getOS() == Triple::Win32; }
246  bool isTargetMingw() const { return TargetTriple.getOS() == Triple::MinGW32; }
247  bool isTargetCygwin() const { return TargetTriple.getOS() == Triple::Cygwin; }
248  bool isTargetCygMing() const { return TargetTriple.isOSCygMing(); }
249  bool isTargetCOFF() const { return TargetTriple.isOSBinFormatCOFF(); }
250  bool isTargetEnvMacho() const { return TargetTriple.isEnvironmentMachO(); }
251
252  bool isTargetWin64() const {
253    // FIXME: x86_64-cygwin has not been released yet.
254    return In64BitMode && TargetTriple.isOSWindows();
255  }
256
257  bool isTargetWin32() const {
258    // FIXME: Cygwin is included for isTargetWin64 -- should it be included
259    // here too?
260    return !In64BitMode && (isTargetMingw() || isTargetWindows());
261  }
262
263  bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
264  bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
265  bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
266
267  bool isPICStyleStubPIC() const {
268    return PICStyle == PICStyles::StubPIC;
269  }
270
271  bool isPICStyleStubNoDynamic() const {
272    return PICStyle == PICStyles::StubDynamicNoPIC;
273  }
274  bool isPICStyleStubAny() const {
275    return PICStyle == PICStyles::StubDynamicNoPIC ||
276           PICStyle == PICStyles::StubPIC; }
277
278  /// ClassifyGlobalReference - Classify a global variable reference for the
279  /// current subtarget according to how we should reference it in a non-pcrel
280  /// context.
281  unsigned char ClassifyGlobalReference(const GlobalValue *GV,
282                                        const TargetMachine &TM)const;
283
284  /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
285  /// current subtarget according to how we should reference it in a non-pcrel
286  /// context.
287  unsigned char ClassifyBlockAddressReference() const;
288
289  /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
290  /// to immediate address.
291  bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
292
293  /// This function returns the name of a function which has an interface
294  /// like the non-standard bzero function, if such a function exists on
295  /// the current subtarget and it is considered prefereable over
296  /// memset with zero passed as the second argument. Otherwise it
297  /// returns null.
298  const char *getBZeroEntry() const;
299
300  /// getSpecialAddressLatency - For targets where it is beneficial to
301  /// backschedule instructions that compute addresses, return a value
302  /// indicating the number of scheduling cycles of backscheduling that
303  /// should be attempted.
304  unsigned getSpecialAddressLatency() const;
305
306  /// enablePostRAScheduler - run for Atom optimization.
307  bool enablePostRAScheduler(CodeGenOpt::Level OptLevel,
308                             TargetSubtargetInfo::AntiDepBreakMode& Mode,
309                             RegClassVector& CriticalPathRCs) const;
310
311  bool postRAScheduler() const { return PostRAScheduler; }
312
313  /// getInstrItins = Return the instruction itineraries based on the
314  /// subtarget selection.
315  const InstrItineraryData &getInstrItineraryData() const { return InstrItins; }
316};
317
318} // End llvm namespace
319
320#endif
321