1//===-- llvm/CodeGen/AsmPrinter/DbgValueHistoryCalculator.h ----*- 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#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DBGVALUEHISTORYCALCULATOR_H
11#define LLVM_LIB_CODEGEN_ASMPRINTER_DBGVALUEHISTORYCALCULATOR_H
12
13#include "llvm/ADT/MapVector.h"
14#include "llvm/ADT/SmallVector.h"
15
16namespace llvm {
17
18class MachineFunction;
19class MachineInstr;
20class DILocalVariable;
21class DILocation;
22class TargetRegisterInfo;
23
24// For each user variable, keep a list of instruction ranges where this variable
25// is accessible. The variables are listed in order of appearance.
26class DbgValueHistoryMap {
27  // Each instruction range starts with a DBG_VALUE instruction, specifying the
28  // location of a variable, which is assumed to be valid until the end of the
29  // range. If end is not specified, location is valid until the start
30  // instruction of the next instruction range, or until the end of the
31  // function.
32public:
33  typedef std::pair<const MachineInstr *, const MachineInstr *> InstrRange;
34  typedef SmallVector<InstrRange, 4> InstrRanges;
35  typedef std::pair<const DILocalVariable *, const DILocation *>
36      InlinedVariable;
37  typedef MapVector<InlinedVariable, InstrRanges> InstrRangesMap;
38
39private:
40  InstrRangesMap VarInstrRanges;
41
42public:
43  void startInstrRange(InlinedVariable Var, const MachineInstr &MI);
44  void endInstrRange(InlinedVariable Var, const MachineInstr &MI);
45  // Returns register currently describing @Var. If @Var is currently
46  // unaccessible or is not described by a register, returns 0.
47  unsigned getRegisterForVar(InlinedVariable Var) const;
48
49  bool empty() const { return VarInstrRanges.empty(); }
50  void clear() { VarInstrRanges.clear(); }
51  InstrRangesMap::const_iterator begin() const { return VarInstrRanges.begin(); }
52  InstrRangesMap::const_iterator end() const { return VarInstrRanges.end(); }
53};
54
55void calculateDbgValueHistory(const MachineFunction *MF,
56                              const TargetRegisterInfo *TRI,
57                              DbgValueHistoryMap &Result);
58}
59
60#endif
61