CodeGenTarget.h revision 2618d07765e94ca12c68c9db31e7843cc69d7178 
1//===- CodeGenTarget.h - Target Class Wrapper -------------------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file was developed by the LLVM research group and is distributed under
6// the University of Illinois Open Source License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines wrappers for the Target class and related global
11// functionality.  This makes it easier to access the data and provides a single
12// place that needs to check it for validity.  All of these classes throw
13// exceptions on error conditions.
14//
15//===----------------------------------------------------------------------===//
16
17#ifndef CODEGEN_TARGET_H
18#define CODEGEN_TARGET_H
19
20#include "CodeGenRegisters.h"
21#include "CodeGenInstruction.h"
22#include <iosfwd>
23#include <map>
24
25namespace llvm {
26
27class Record;
28class RecordKeeper;
29struct CodeGenRegister;
30class CodeGenTarget;
31
32/// getValueType - Return the MVT::ValueType that the specified TableGen record
33/// corresponds to.
34MVT::ValueType getValueType(Record *Rec, const CodeGenTarget *CGT = 0);
35
36std::ostream &operator<<(std::ostream &OS, MVT::ValueType T);
37std::string getName(MVT::ValueType T);
38std::string getEnumName(MVT::ValueType T);
39
40
41/// CodeGenTarget - This class corresponds to the Target class in the .td files.
42///
43class CodeGenTarget {
44  Record *TargetRec;
45  std::vector<Record*> CalleeSavedRegisters;
46
47  mutable std::map<std::string, CodeGenInstruction> Instructions;
48  mutable std::vector<CodeGenRegister> Registers;
49  mutable std::vector<CodeGenRegisterClass> RegisterClasses;
50  mutable std::vector<MVT::ValueType> LegalValueTypes;
51  void ReadRegisters() const;
52  void ReadRegisterClasses() const;
53  void ReadInstructions() const;
54  void ReadLegalValueTypes() const;
55public:
56  CodeGenTarget();
57
58  Record *getTargetRecord() const { return TargetRec; }
59  const std::string &getName() const;
60
61  const std::vector<Record*> &getCalleeSavedRegisters() const {
62    return CalleeSavedRegisters;
63  }
64
65  /// getInstructionSet - Return the InstructionSet object.
66  ///
67  Record *getInstructionSet() const;
68
69  /// getAsmWriter - Return the AssemblyWriter definition for this target.
70  ///
71  Record *getAsmWriter() const;
72
73  const std::vector<CodeGenRegister> &getRegisters() const {
74    if (Registers.empty()) ReadRegisters();
75    return Registers;
76  }
77
78  const std::vector<CodeGenRegisterClass> &getRegisterClasses() const {
79    if (RegisterClasses.empty()) ReadRegisterClasses();
80    return RegisterClasses;
81  }
82
83  const CodeGenRegisterClass &getRegisterClass(Record *R) const {
84    const std::vector<CodeGenRegisterClass> &RC = getRegisterClasses();
85    for (unsigned i = 0, e = RC.size(); i != e; ++i)
86      if (RC[i].TheDef == R)
87        return RC[i];
88    assert(0 && "Didn't find the register class");
89    abort();
90  }
91
92  /// getRegisterClassForRegister - Find the register class that contains the
93  /// specified physical register.  If there register exists in multiple
94  /// register classes or is not in a register class, return null.
95  const CodeGenRegisterClass *getRegisterClassForRegister(Record *R) const {
96    const std::vector<CodeGenRegisterClass> &RCs = getRegisterClasses();
97    const CodeGenRegisterClass *FoundRC = 0;
98    for (unsigned i = 0, e = RCs.size(); i != e; ++i) {
99      const CodeGenRegisterClass &RC = RegisterClasses[i];
100      for (unsigned ei = 0, ee = RC.Elements.size(); ei != ee; ++ei) {
101        if (R == RC.Elements[ei]) {
102          if (FoundRC) return 0;  // In multiple RC's
103          FoundRC = &RC;
104          break;
105        }
106      }
107    }
108    return FoundRC;
109  }
110
111  /// getRegisterVTs - Find the union of all possible ValueTypes for the
112  /// specified physical register.
113  std::vector<unsigned char> getRegisterVTs(Record *R) const;
114
115  const std::vector<MVT::ValueType> &getLegalValueTypes() const {
116    if (LegalValueTypes.empty()) ReadLegalValueTypes();
117    return LegalValueTypes;
118  }
119
120  /// isLegalValueType - Return true if the specified value type is natively
121  /// supported by the target (i.e. there are registers that directly hold it).
122  bool isLegalValueType(MVT::ValueType VT) const {
123    const std::vector<MVT::ValueType> &LegalVTs = getLegalValueTypes();
124    for (unsigned i = 0, e = LegalVTs.size(); i != e; ++i)
125      if (LegalVTs[i] == VT) return true;
126    return false;
127  }
128
129  /// getInstructions - Return all of the instructions defined for this target.
130  ///
131  const std::map<std::string, CodeGenInstruction> &getInstructions() const {
132    if (Instructions.empty()) ReadInstructions();
133    return Instructions;
134  }
135
136  CodeGenInstruction &getInstruction(const std::string &Name) const {
137    const std::map<std::string, CodeGenInstruction> &Insts = getInstructions();
138    assert(Insts.count(Name) && "Not an instruction!");
139    return const_cast<CodeGenInstruction&>(Insts.find(Name)->second);
140  }
141
142  typedef std::map<std::string,
143                   CodeGenInstruction>::const_iterator inst_iterator;
144  inst_iterator inst_begin() const { return getInstructions().begin(); }
145  inst_iterator inst_end() const { return Instructions.end(); }
146
147  /// getInstructionsByEnumValue - Return all of the instructions defined by the
148  /// target, ordered by their enum value.
149  void getInstructionsByEnumValue(std::vector<const CodeGenInstruction*>
150                                                &NumberedInstructions);
151
152
153  /// isLittleEndianEncoding - are instruction bit patterns defined as  [0..n]?
154  ///
155  bool isLittleEndianEncoding() const;
156};
157
158/// ComplexPattern - ComplexPattern info, corresponding to the ComplexPattern
159/// tablegen class in TargetSelectionDAG.td
160class ComplexPattern {
161  MVT::ValueType Ty;
162  unsigned NumOperands;
163  std::string SelectFunc;
164  std::vector<Record*> RootNodes;
165public:
166  ComplexPattern() : NumOperands(0) {};
167  ComplexPattern(Record *R);
168
169  MVT::ValueType getValueType() const { return Ty; }
170  unsigned getNumOperands() const { return NumOperands; }
171  const std::string &getSelectFunc() const { return SelectFunc; }
172  const std::vector<Record*> &getRootNodes() const {
173    return RootNodes;
174  }
175};
176
177} // End llvm namespace
178
179#endif
180