X86Subtarget.h revision 4d3d6e1a0c99e2212953a90185a8d027c595bf5a 
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 "llvm/CallingConv.h"
19#include <string>
20
21namespace llvm {
22class GlobalValue;
23class TargetMachine;
24
25/// PICStyles - The X86 backend supports a number of different styles of PIC.
26///
27namespace PICStyles {
28enum 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
37class X86Subtarget : public TargetSubtarget {
38protected:
39  enum X86SSEEnum {
40    NoMMXSSE, MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42
41  };
42
43  enum X863DNowEnum {
44    NoThreeDNow, ThreeDNow, ThreeDNowA
45  };
46
47  /// PICStyle - Which PIC style to use
48  ///
49  PICStyles::Style PICStyle;
50
51  /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
52  /// none supported.
53  X86SSEEnum X86SSELevel;
54
55  /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
56  ///
57  X863DNowEnum X863DNowLevel;
58
59  /// HasCMov - True if this processor has conditional move instructions
60  /// (generally pentium pro+).
61  bool HasCMov;
62
63  /// HasX86_64 - True if the processor supports X86-64 instructions.
64  ///
65  bool HasX86_64;
66
67  /// HasSSE4A - True if the processor supports SSE4A instructions.
68  bool HasSSE4A;
69
70  /// HasAVX - Target has AVX instructions
71  bool HasAVX;
72
73  /// HasAES - Target has AES instructions
74  bool HasAES;
75
76  /// HasFMA3 - Target has 3-operand fused multiply-add
77  bool HasFMA3;
78
79  /// HasFMA4 - Target has 4-operand fused multiply-add
80  bool HasFMA4;
81
82  /// IsBTMemSlow - True if BT (bit test) of memory instructions are slow.
83  bool IsBTMemSlow;
84
85  /// IsUAMemFast - True if unaligned memory access is fast.
86  bool IsUAMemFast;
87
88  /// HasVectorUAMem - True if SIMD operations can have unaligned memory
89  /// operands. This may require setting a feature bit in the processor.
90  bool HasVectorUAMem;
91
92  /// DarwinVers - Nonzero if this is a darwin platform: the numeric
93  /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
94  unsigned char DarwinVers; // Is any darwin-x86 platform.
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
104private:
105  /// Is64Bit - True if the processor supports 64-bit instructions and
106  /// pointer size is 64 bit.
107  bool Is64Bit;
108
109public:
110  enum {
111    isELF, isCygwin, isDarwin, isWindows, isMingw
112  } TargetType;
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 hasFMA3() const { return HasFMA3; }
156  bool hasFMA4() const { return HasFMA4; }
157  bool isBTMemSlow() const { return IsBTMemSlow; }
158  bool isUnalignedMemAccessFast() const { return IsUAMemFast; }
159  bool hasVectorUAMem() const { return HasVectorUAMem; }
160
161  bool isTargetDarwin() const { return TargetType == isDarwin; }
162  bool isTargetELF() const { return TargetType == isELF; }
163
164  bool isTargetWindows() const { return TargetType == isWindows; }
165  bool isTargetMingw() const { return TargetType == isMingw; }
166  bool isTargetCygwin() const { return TargetType == isCygwin; }
167  bool isTargetCygMing() const {
168    return TargetType == isMingw || TargetType == isCygwin;
169  }
170
171  /// isTargetCOFF - Return true if this is any COFF/Windows target variant.
172  bool isTargetCOFF() const {
173    return TargetType == isMingw || TargetType == isCygwin ||
174           TargetType == isWindows;
175  }
176
177  bool isTargetWin64() const {
178    return Is64Bit && (TargetType == isMingw || TargetType == isWindows);
179  }
180
181  std::string getDataLayout() const {
182    const char *p;
183    if (is64Bit())
184      p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128-n8:16:32:64";
185    else if (isTargetDarwin())
186      p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128-n8:16:32";
187    else if (isTargetMingw() || isTargetWindows())
188      p = "e-p:32:32-f64:64:64-i64:64:64-f80:32:32-n8:16:32";
189    else
190      p = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32-n8:16:32";
191
192    return std::string(p);
193  }
194
195  bool isPICStyleSet() const { return PICStyle != PICStyles::None; }
196  bool isPICStyleGOT() const { return PICStyle == PICStyles::GOT; }
197  bool isPICStyleRIPRel() const { return PICStyle == PICStyles::RIPRel; }
198
199  bool isPICStyleStubPIC() const {
200    return PICStyle == PICStyles::StubPIC;
201  }
202
203  bool isPICStyleStubNoDynamic() const {
204    return PICStyle == PICStyles::StubDynamicNoPIC;
205  }
206  bool isPICStyleStubAny() const {
207    return PICStyle == PICStyles::StubDynamicNoPIC ||
208           PICStyle == PICStyles::StubPIC; }
209
210  /// getDarwinVers - Return the darwin version number, 8 = Tiger, 9 = Leopard,
211  /// 10 = Snow Leopard, etc.
212  unsigned getDarwinVers() const { return DarwinVers; }
213
214  /// ClassifyGlobalReference - Classify a global variable reference for the
215  /// current subtarget according to how we should reference it in a non-pcrel
216  /// context.
217  unsigned char ClassifyGlobalReference(const GlobalValue *GV,
218                                        const TargetMachine &TM)const;
219
220  /// ClassifyBlockAddressReference - Classify a blockaddress reference for the
221  /// current subtarget according to how we should reference it in a non-pcrel
222  /// context.
223  unsigned char ClassifyBlockAddressReference() const;
224
225  /// IsLegalToCallImmediateAddr - Return true if the subtarget allows calls
226  /// to immediate address.
227  bool IsLegalToCallImmediateAddr(const TargetMachine &TM) const;
228
229  /// This function returns the name of a function which has an interface
230  /// like the non-standard bzero function, if such a function exists on
231  /// the current subtarget and it is considered prefereable over
232  /// memset with zero passed as the second argument. Otherwise it
233  /// returns null.
234  const char *getBZeroEntry() const;
235
236  /// getSpecialAddressLatency - For targets where it is beneficial to
237  /// backschedule instructions that compute addresses, return a value
238  /// indicating the number of scheduling cycles of backscheduling that
239  /// should be attempted.
240  unsigned getSpecialAddressLatency() const;
241
242  /// IsCalleePop - Test whether a function should pop its own arguments.
243  bool IsCalleePop(bool isVarArg, CallingConv::ID CallConv) const;
244};
245
246} // End llvm namespace
247
248#endif
249