X86Subtarget.h revision b4e56d4a2bc5a18507b2d255abf75f7850f41c04 
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
19#include <string>
20
21namespace llvm {
22class Module;
23class GlobalValue;
24class TargetMachine;
25
26namespace PICStyle {
27enum Style {
28  Stub, GOT, RIPRel, WinPIC, None
29};
30}
31
32class X86Subtarget : public TargetSubtarget {
33public:
34  enum AsmWriterFlavorTy {
35    // Note: This numbering has to match the GCC assembler dialects for inline
36    // asm alternatives to work right.
37    ATT = 0, Intel = 1, Unset
38  };
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  /// AsmFlavor - Which x86 asm dialect to use.
49  ///
50  AsmWriterFlavorTy AsmFlavor;
51
52  /// PICStyle - Which PIC style to use
53  ///
54  PICStyle::Style PICStyle;
55
56  /// X86SSELevel - MMX, SSE1, SSE2, SSE3, SSSE3, SSE41, SSE42, or
57  /// none supported.
58  X86SSEEnum X86SSELevel;
59
60  /// X863DNowLevel - 3DNow or 3DNow Athlon, or none supported.
61  ///
62  X863DNowEnum X863DNowLevel;
63
64  /// HasX86_64 - True if the processor supports X86-64 instructions.
65  ///
66  bool HasX86_64;
67
68  /// DarwinVers - Nonzero if this is a darwin platform: the numeric
69  /// version of the platform, e.g. 8 = 10.4 (Tiger), 9 = 10.5 (Leopard), etc.
70  unsigned char DarwinVers; // Is any darwin-ppc platform.
71
72  /// stackAlignment - The minimum alignment known to hold of the stack frame on
73  /// entry to the function and which must be maintained by every function.
74  unsigned stackAlignment;
75
76  /// Max. memset / memcpy size that is turned into rep/movs, rep/stos ops.
77  ///
78  unsigned MaxInlineSizeThreshold;
79
80private:
81  /// Is64Bit - True if the processor supports 64-bit instructions and module
82  /// pointer size is 64 bit.
83  bool Is64Bit;
84
85public:
86  enum {
87    isELF, isCygwin, isDarwin, isWindows, isMingw
88  } TargetType;
89
90  /// This constructor initializes the data members to match that
91  /// of the specified module.
92  ///
93  X86Subtarget(const Module &M, const std::string &FS, bool is64Bit);
94
95  /// getStackAlignment - Returns the minimum alignment known to hold of the
96  /// stack frame on entry to the function and which must be maintained by every
97  /// function for this subtarget.
98  unsigned getStackAlignment() const { return stackAlignment; }
99
100  /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
101  /// that still makes it profitable to inline the call.
102  unsigned getMaxInlineSizeThreshold() const { return MaxInlineSizeThreshold; }
103
104  /// ParseSubtargetFeatures - Parses features string setting specified
105  /// subtarget options.  Definition of function is auto generated by tblgen.
106  void ParseSubtargetFeatures(const std::string &FS, const std::string &CPU);
107
108  /// AutoDetectSubtargetFeatures - Auto-detect CPU features using CPUID
109  /// instruction.
110  void AutoDetectSubtargetFeatures();
111
112  bool is64Bit() const { return Is64Bit; }
113
114  PICStyle::Style getPICStyle() const { return PICStyle; }
115  void setPICStyle(PICStyle::Style Style)  { PICStyle = Style; }
116
117  bool hasMMX() const { return X86SSELevel >= MMX; }
118  bool hasSSE1() const { return X86SSELevel >= SSE1; }
119  bool hasSSE2() const { return X86SSELevel >= SSE2; }
120  bool hasSSE3() const { return X86SSELevel >= SSE3; }
121  bool hasSSSE3() const { return X86SSELevel >= SSSE3; }
122  // Temporarily disabling SSE4.
123  bool hasSSE41() const { return false && X86SSELevel >= SSE41; }
124  bool hasSSE42() const { return false && X86SSELevel >= SSE42; }
125  bool has3DNow() const { return X863DNowLevel >= ThreeDNow; }
126  bool has3DNowA() const { return X863DNowLevel >= ThreeDNowA; }
127
128  unsigned getAsmFlavor() const {
129    return AsmFlavor != Unset ? unsigned(AsmFlavor) : 0;
130  }
131
132  bool isFlavorAtt() const { return AsmFlavor == ATT; }
133  bool isFlavorIntel() const { return AsmFlavor == Intel; }
134
135  bool isTargetDarwin() const { return TargetType == isDarwin; }
136  bool isTargetELF() const { return TargetType == isELF; }
137  bool isTargetWindows() const { return TargetType == isWindows; }
138  bool isTargetMingw() const { return TargetType == isMingw; }
139  bool isTargetCygMing() const { return (TargetType == isMingw ||
140                                         TargetType == isCygwin); }
141  bool isTargetCygwin() const { return TargetType == isCygwin; }
142  bool isTargetWin64() const {
143    return (Is64Bit && (TargetType == isMingw || TargetType == isWindows));
144  }
145
146  std::string getDataLayout() const {
147    const char *p;
148    if (is64Bit())
149      p = "e-p:64:64-s:64-f64:64:64-i64:64:64-f80:128:128";
150    else {
151      if (isTargetDarwin())
152        p = "e-p:32:32-f64:32:64-i64:32:64-f80:128:128";
153      else
154        p = "e-p:32:32-f64:32:64-i64:32:64-f80:32:32";
155    }
156    return std::string(p);
157  }
158
159  bool isPICStyleSet() const { return PICStyle != PICStyle::None; }
160  bool isPICStyleGOT() const { return PICStyle == PICStyle::GOT; }
161  bool isPICStyleStub() const { return PICStyle == PICStyle::Stub; }
162  bool isPICStyleRIPRel() const { return PICStyle == PICStyle::RIPRel; }
163  bool isPICStyleWinPIC() const { return PICStyle == PICStyle:: WinPIC; }
164
165  /// getDarwinVers - Return the darwin version number, 8 = tiger, 9 = leopard.
166  unsigned getDarwinVers() const { return DarwinVers; }
167
168  /// True if accessing the GV requires an extra load. For Windows, dllimported
169  /// symbols are indirect, loading the value at address GV rather then the
170  /// value of GV itself. This means that the GlobalAddress must be in the base
171  /// or index register of the address, not the GV offset field.
172  bool GVRequiresExtraLoad(const GlobalValue* GV, const TargetMachine& TM,
173                           bool isDirectCall) const;
174
175  /// This function returns the name of a function which has an interface
176  /// like the non-standard bzero function, if such a function exists on
177  /// the current subtarget and it is considered prefereable over
178  /// memset with zero passed as the second argument. Otherwise it
179  /// returns null.
180  const char *getBZeroEntry() const;
181};
182
183namespace X86 {
184  /// GetCpuIDAndInfo - Execute the specified cpuid and return the 4 values in
185  /// the specified arguments.  If we can't run cpuid on the host, return true.
186  bool GetCpuIDAndInfo(unsigned value, unsigned *rEAX, unsigned *rEBX,
187                       unsigned *rECX, unsigned *rEDX);
188}
189
190} // End llvm namespace
191
192#endif
193