ARMSubtarget.h revision 42a83f2d15cbbc08f5be19856198e3c885221e9c 
1//=====---- ARMSubtarget.h - Define Subtarget for the ARM -----*- 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 ARM specific subclass of TargetSubtarget.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef ARMSUBTARGET_H
15#define ARMSUBTARGET_H
16
17#include "llvm/Target/TargetInstrItineraries.h"
18#include "llvm/Target/TargetSubtarget.h"
19#include <string>
20
21namespace llvm {
22
23class ARMSubtarget : public TargetSubtarget {
24protected:
25  enum ARMArchEnum {
26    V4T, V5T, V5TE, V6, V6T2, V7A
27  };
28
29  enum ARMFPEnum {
30    None, VFPv2, VFPv3, NEON
31  };
32
33  enum ThumbTypeEnum {
34    Thumb1,
35    Thumb2
36  };
37
38  /// ARMArchVersion - ARM architecture version: V4T (base), V5T, V5TE,
39  /// V6, V6T2, V7A.
40  ARMArchEnum ARMArchVersion;
41
42  /// ARMFPUType - Floating Point Unit type.
43  ARMFPEnum ARMFPUType;
44
45  /// UseNEONForSinglePrecisionFP - if NEON is available use for FP
46  bool UseNEONForSinglePrecisionFP;
47
48  /// IsThumb - True if we are in thumb mode, false if in ARM mode.
49  bool IsThumb;
50
51  /// ThumbMode - Indicates supported Thumb version.
52  ThumbTypeEnum ThumbMode;
53
54  /// IsR9Reserved - True if R9 is a not available as general purpose register.
55  bool IsR9Reserved;
56
57  /// stackAlignment - The minimum alignment known to hold of the stack frame on
58  /// entry to the function and which must be maintained by every function.
59  unsigned stackAlignment;
60
61  /// CPUString - String name of used CPU.
62  std::string CPUString;
63
64  /// Selected instruction itineraries (one entry per itinerary class.)
65  InstrItineraryData InstrItins;
66
67 public:
68  enum {
69    isELF, isDarwin
70  } TargetType;
71
72  enum {
73    ARM_ABI_APCS,
74    ARM_ABI_AAPCS // ARM EABI
75  } TargetABI;
76
77  /// This constructor initializes the data members to match that
78  /// of the specified triple.
79  ///
80  ARMSubtarget(const std::string &TT, const std::string &FS, bool isThumb);
81
82  /// getMaxInlineSizeThreshold - Returns the maximum memset / memcpy size
83  /// that still makes it profitable to inline the call.
84  unsigned getMaxInlineSizeThreshold() const {
85    // FIXME: For now, we don't lower memcpy's to loads / stores for Thumb.
86    // Change this once Thumb ldmia / stmia support is added.
87    return isThumb() ? 0 : 64;
88  }
89  /// ParseSubtargetFeatures - Parses features string setting specified
90  /// subtarget options.  Definition of function is auto generated by tblgen.
91  std::string ParseSubtargetFeatures(const std::string &FS,
92                                     const std::string &CPU);
93
94  bool hasV4TOps()  const { return ARMArchVersion >= V4T;  }
95  bool hasV5TOps()  const { return ARMArchVersion >= V5T;  }
96  bool hasV5TEOps() const { return ARMArchVersion >= V5TE; }
97  bool hasV6Ops()   const { return ARMArchVersion >= V6;   }
98  bool hasV6T2Ops() const { return ARMArchVersion >= V6T2; }
99  bool hasV7Ops()   const { return ARMArchVersion >= V7A;  }
100
101  bool hasVFP2() const { return ARMFPUType >= VFPv2; }
102  bool hasVFP3() const { return ARMFPUType >= VFPv3; }
103  bool hasNEON() const { return ARMFPUType >= NEON;  }
104  bool useNEONForSinglePrecisionFP() const {
105    return hasNEON() && UseNEONForSinglePrecisionFP; }
106
107  bool isTargetDarwin() const { return TargetType == isDarwin; }
108  bool isTargetELF() const { return TargetType == isELF; }
109
110  bool isAPCS_ABI() const { return TargetABI == ARM_ABI_APCS; }
111  bool isAAPCS_ABI() const { return TargetABI == ARM_ABI_AAPCS; }
112
113  bool isThumb() const { return IsThumb; }
114  bool isThumb1Only() const { return IsThumb && (ThumbMode == Thumb1); }
115  bool isThumb2() const { return IsThumb && (ThumbMode == Thumb2); }
116  bool hasThumb2() const { return ThumbMode >= Thumb2; }
117
118  bool isR9Reserved() const { return IsR9Reserved; }
119
120  const std::string & getCPUString() const { return CPUString; }
121
122  /// getInstrItins - Return the instruction itineraies based on subtarget
123  /// selection.
124  const InstrItineraryData &getInstrItineraryData() const { return InstrItins; }
125
126  /// getStackAlignment - Returns the minimum alignment known to hold of the
127  /// stack frame on entry to the function and which must be maintained by every
128  /// function for this subtarget.
129  unsigned getStackAlignment() const { return stackAlignment; }
130};
131} // End llvm namespace
132
133#endif  // ARMSUBTARGET_H
134