X86Subtarget.h revision 24cfd06d031da285286a330c1fbc61127643dd2d 
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 &FS, bool is64Bit);
121
122  /// getStackAlignment - Returns the minimum alignment known to hold of the
123  /// stack frame on entry to the function and which must be maintained by every
124  /// function for this subtarget.
125  unsigned getStackAlignment() const { return stackAlignment; }
126
127  /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
128  /// that still makes it profitable to inline the call.
129  unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
130
131  /// ParseSubtargetFeatures - Parses features string setting specified
132  /// subtarget options.  Definition of function is auto generated by tblgen.
133  std::string ParseSubtargetFeatures(const std::string &FS,
134                                     const std::string &CPU);
135
136  /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
137  /// instruction.
138  void AutoDetectSubtargetFeatures();
139
140  bool is64Bit() const { return Is64Bit; }
141
142  PICStyles::Style getPICStyle() const { return PICStyle; }
143  void setPICStyle(PICStyles::Style Style)  { PICStyle = Style; }
144
145  bool hasCMov() const { return HasCMov; }
146  bool hasMMX() const { return X86SSELevel >= MMX; }
147  bool hasSSE1() const { return X86SSELevel >= SSE1; }
148  bool hasSSE2() const { return X86SSELevel >= SSE2; }
149  bool hasSSE3() const { return X86SSELevel >= SSE3; }
150  bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
151  bool hasSSE41() const { return X86SSELevel >= SSE41; }
152  bool hasSSE42() const { return X86SSELevel >= SSE42; }
153  bool hasSSE4A() const { return HasSSE4A; }
154  bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
155  bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
156  bool hasPOPCNT() const { return HasPOPCNT; }
157  bool hasAVX() const { return HasAVX; }
158  bool hasXMM() const { return hasSSE1() || hasAVX(); }
159  bool hasXMMInt() const { return hasSSE2() || hasAVX(); }
160  bool hasAES() const { return HasAES; }
161  bool hasCLMUL() const { return HasCLMUL; }
162  bool hasFMA3() const { return HasFMA3; }
163  bool hasFMA4() const { return HasFMA4; }
164  bool isBTMemSlow() const { return IsBTMemSlow; }
165  bool isUnalignedMemAccessFast() const { return IsUAMemFast; }
166  bool hasVectorUAMem() const { return HasVectorUAMem; }
167
168  const Triple &getTargetTriple() const { return TargetTriple; }
169
170  bool isTargetDarwin() const { return TargetTriple.getOS() == Triple::Darwin; }
171  bool isTargetFreeBSD() const { return TargetTriple.getOS() == Triple::FreeBSD; }
172  bool isTargetSolaris() const { return TargetTriple.getOS() == Triple::Solaris; }
173
174  // ELF is a reasonably sane default and the only other X86 targets we
175  // support are Darwin and Windows. Just use "not those".
176  bool isTargetELF() const {
177    return !isTargetDarwin() && !isTargetWindows() && !isTargetCygMing();
178  }
179  bool isTargetLinux() const { return TargetTriple.getOS() == Triple::Linux; }
180
181  bool isTargetWindows() const { return TargetTriple.getOS() == Triple::Win32; }
182  bool isTargetMingw() const { return TargetTriple.getOS() == Triple::MinGW32; }
183  bool isTargetCygwin() const { return TargetTriple.getOS() == Triple::Cygwin; }
184  bool isTargetCygMing() const {
185    return isTargetMingw() || isTargetCygwin();
186  }
187
188  /// isTargetCOFF - Return true if this is any COFF/Windows target variant.
189  bool isTargetCOFF() const {
190    return isTargetMingw() || isTargetCygwin() || isTargetWindows();
191  }
192
193  bool isTargetWin64() const {
194    return Is64Bit && (isTargetMingw() || isTargetWindows());
195  }
196
197  bool isTargetEnvMacho() const {
198    return isTargetDarwin() || (TargetTriple.getEnvironment() == Triple::MachO);
199  }
200
201  bool isTargetWin32() const {
202    return !Is64Bit && (isTargetMingw() || isTargetWindows());
203  }
204
205  bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
206  bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
207  bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
208
209  bool isPICStyleStubPIC() const {
210    return PICStyle == PICStyles::StubPIC;
211  }
212
213  bool isPICStyleStubNoDynamic() const {
214    return PICStyle == PICStyles::StubDynamicNoPIC;
215  }
216  bool isPICStyleStubAny() const {
217    return PICStyle == PICStyles::StubDynamicNoPIC ||
218           PICStyle == PICStyles::StubPIC; }
219
220  /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
221  /// 10 = Snow Leopard, etc.
222  unsigned getDarwinVers() const {
223    if (isTargetDarwin()) return TargetTriple.getDarwinMajorNumber();
224    return 0;
225  }
226
227  /// ClassifyGlobalReference - Classify a global variable reference for the
228  /// current subtarget according to how we should reference it in a non-pcrel
229  /// context.
230  unsigned char ClassifyGlobalReference(const GlobalValue *GV,
231                                        const TargetMachine &TM)const;
232
233  /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
234  /// current subtarget according to how we should reference it in a non-pcrel
235  /// context.
236  unsigned char ClassifyBlockAddressReference() const;
237
238  /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
239  /// to immediate address.
240  bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
241
242  /// This function returns the name of a function which has an interface
243  /// like the non-standard bzero function, if such a function exists on
244  /// the current subtarget and it is considered prefereable over
245  /// memset with zero passed as the second argument. Otherwise it
246  /// returns null.
247  const char *getBZeroEntry() const;
248
249  /// getSpecialAddressLatency - For targets where it is beneficial to
250  /// backschedule instructions that compute addresses, return a value
251  /// indicating the number of scheduling cycles of backscheduling that
252  /// should be attempted.
253  unsigned getSpecialAddressLatency() const;
254
255  /// IsCalleePop - Test whether a function should pop its own arguments.
256  bool IsCalleePop(bool isVarArg, CallingConv::ID CallConv) const;
257};
258
259} // End llvm namespace
260
261#endif
262