X86Subtarget.h revision 276365dd4bc0c2160f91fd8062ae1fc90c86c324 
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
22namespace llvm {
23class GlobalValue;
24class TargetMachine;
25
26/// PICStyles - The X86 backend supports a number of different styles of PIC.
27///
28namespace PICStyles {
29enum 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
38class X86Subtarget : public TargetSubtarget {
39protected:
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  /// HasPOPCNT - True if the processor supports POPCNT.
69  bool HasPOPCNT;
70
71  /// HasSSE4A - True if the processor supports SSE4A instructions.
72  bool HasSSE4A;
73
74  /// HasAVX - Target has AVX instructions
75  bool HasAVX;
76
77  /// HasAES - Target has AES instructions
78  bool HasAES;
79
80  /// HasCLMUL - Target has carry-less multiplication
81  bool HasCLMUL;
82
83  /// HasFMA3 - Target has 3-operand fused multiply-add
84  bool HasFMA3;
85
86  /// HasFMA4 - Target has 4-operand fused multiply-add
87  bool HasFMA4;
88
89  /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
90  bool IsBTMemSlow;
91
92  /// IsUAMemFast - True if unaligned memory access is fast.
93  bool IsUAMemFast;
94
95  /// HasVectorUAMem - True if SIMD operations can have unaligned memory
96  /// operands. This may require setting a feature bit in the processor.
97  bool HasVectorUAMem;
98
99  /// stackAlignment - The minimum alignment known to hold of the stack frame on
100  /// entry to the function and which must be maintained by every function.
101  unsigned stackAlignment;
102
103  /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
104  ///
105  unsigned MaxInlineSizeThreshold;
106
107  /// TargetTriple - What processor and OS we're targeting.
108  Triple TargetTriple;
109
110private:
111  /// Is64Bit - True if the processor supports 64-bit instructions and
112  /// pointer size is 64 bit.
113  bool Is64Bit;
114
115public:
116
117  /// This constructor initializes the data members to match that
118  /// of the specified triple.
119  ///
120  X86Subtarget(const std::string &TT, const std::string &CPU,
121               const std::string &FS, bool is64Bit,
122               unsigned StackAlignOverride);
123
124  /// getStackAlignment - Returns the minimum alignment known to hold of the
125  /// stack frame on entry to the function and which must be maintained by every
126  /// function for this subtarget.
127  unsigned getStackAlignment() const { return stackAlignment; }
128
129  /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
130  /// that still makes it profitable to inline the call.
131  unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
132
133  /// ParseSubtargetFeatures - Parses features string setting specified
134  /// subtarget options.  Definition of function is auto generated by tblgen.
135  void ParseSubtargetFeatures(const std::string &FS, const std::string &CPU);
136
137  /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
138  /// instruction.
139  void AutoDetectSubtargetFeatures();
140
141  bool is64Bit() const { return Is64Bit; }
142
143  PICStyles::Style getPICStyle() const { return PICStyle; }
144  void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
145
146  bool hasCMov() const { return HasCMov; }
147  bool hasMMX() const { return X86SSELevel >= MMX; }
148  bool hasSSE1() const { return X86SSELevel >= SSE1; }
149  bool hasSSE2() const { return X86SSELevel >= SSE2; }
150  bool hasSSE3() const { return X86SSELevel >= SSE3; }
151  bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
152  bool hasSSE41() const { return X86SSELevel >= SSE41; }
153  bool hasSSE42() const { return X86SSELevel >= SSE42; }
154  bool hasSSE4A() const { return HasSSE4A; }
155  bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
156  bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
157  bool hasPOPCNT() const { return HasPOPCNT; }
158  bool hasAVX() const { return HasAVX; }
159  bool hasXMM() const { return hasSSE1() || hasAVX(); }
160  bool hasXMMInt() const { return hasSSE2() || hasAVX(); }
161  bool hasAES() const { return HasAES; }
162  bool hasCLMUL() const { return HasCLMUL; }
163  bool hasFMA3() const { return HasFMA3; }
164  bool hasFMA4() const { return HasFMA4; }
165  bool isBTMemSlow() const { return IsBTMemSlow; }
166  bool isUnalignedMemAccessFast() const { return IsUAMemFast; }
167  bool hasVectorUAMem() const { return HasVectorUAMem; }
168
169  const Triple &getTargetTriple() const { return TargetTriple; }
170
171  bool isTargetDarwin() const { return TargetTriple.isOSDarwin(); }
172  bool isTargetFreeBSD() const {
173    return TargetTriple.getOS() == Triple::FreeBSD;
174  }
175  bool isTargetSolaris() const {
176    return TargetTriple.getOS() == Triple::Solaris;
177  }
178
179  // ELF is a reasonably sane default and the only other X86 targets we
180  // support are Darwin and Windows. Just use "not those".
181  bool isTargetELF() const {
182    return !isTargetDarwin() && !isTargetWindows() && !isTargetCygMing();
183  }
184  bool isTargetLinux() const { return TargetTriple.getOS() == Triple::Linux; }
185
186  bool isTargetWindows() const { return TargetTriple.getOS() == Triple::Win32; }
187  bool isTargetMingw() const { return TargetTriple.getOS() == Triple::MinGW32; }
188  bool isTargetCygwin() const { return TargetTriple.getOS() == Triple::Cygwin; }
189  bool isTargetCygMing() const {
190    return isTargetMingw() || isTargetCygwin();
191  }
192
193  /// isTargetCOFF - Return true if this is any COFF/Windows target variant.
194  bool isTargetCOFF() const {
195    return isTargetMingw() || isTargetCygwin() || isTargetWindows();
196  }
197
198  bool isTargetWin64() const {
199    return Is64Bit && (isTargetMingw() || isTargetWindows());
200  }
201
202  bool isTargetEnvMacho() const {
203    return isTargetDarwin() || (TargetTriple.getEnvironment() == Triple::MachO);
204  }
205
206  bool isTargetWin32() const {
207    return !Is64Bit && (isTargetMingw() || isTargetWindows());
208  }
209
210  bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
211  bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
212  bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
213
214  bool isPICStyleStubPIC() const {
215    return PICStyle == PICStyles::StubPIC;
216  }
217
218  bool isPICStyleStubNoDynamic() const {
219    return PICStyle == PICStyles::StubDynamicNoPIC;
220  }
221  bool isPICStyleStubAny() const {
222    return PICStyle == PICStyles::StubDynamicNoPIC ||
223           PICStyle == PICStyles::StubPIC; }
224
225  /// ClassifyGlobalReference - Classify a global variable reference for the
226  /// current subtarget according to how we should reference it in a non-pcrel
227  /// context.
228  unsigned char ClassifyGlobalReference(const GlobalValue *GV,
229                                        const TargetMachine &TM)const;
230
231  /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
232  /// current subtarget according to how we should reference it in a non-pcrel
233  /// context.
234  unsigned char ClassifyBlockAddressReference() const;
235
236  /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
237  /// to immediate address.
238  bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
239
240  /// This function returns the name of a function which has an interface
241  /// like the non-standard bzero function, if such a function exists on
242  /// the current subtarget and it is considered prefereable over
243  /// memset with zero passed as the second argument. Otherwise it
244  /// returns null.
245  const char *getBZeroEntry() const;
246
247  /// getSpecialAddressLatency - For targets where it is beneficial to
248  /// backschedule instructions that compute addresses, return a value
249  /// indicating the number of scheduling cycles of backscheduling that
250  /// should be attempted.
251  unsigned getSpecialAddressLatency() const;
252};
253
254} // End llvm namespace
255
256#endif
257