1 //===-- llvm/CodeGen/SDNodeDbgValue.h - SelectionDAG dbg_value --*- 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 SDDbgValue class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_LIB_CODEGEN_SELECTIONDAG_SDNODEDBGVALUE_H
15 #define LLVM_LIB_CODEGEN_SELECTIONDAG_SDNODEDBGVALUE_H
16 
17 #include "llvm/IR/DebugLoc.h"
18 #include "llvm/Support/DataTypes.h"
19 #include <utility>
20 
21 namespace llvm {
22 
23 class DIVariable;
24 class DIExpression;
25 class SDNode;
26 class Value;
27 class raw_ostream;
28 
29 /// Holds the information from a dbg_value node through SDISel.
30 /// We do not use SDValue here to avoid including its header.
31 class SDDbgValue {
32 public:
33   enum DbgValueKind {
34     SDNODE = 0,             ///< Value is the result of an expression.
35     CONST = 1,              ///< Value is a constant.
36     FRAMEIX = 2,            ///< Value is contents of a stack location.
37     VREG = 3                ///< Value is a virtual register.
38   };
39 private:
40   union {
41     struct {
42       SDNode *Node;         ///< Valid for expressions.
43       unsigned ResNo;       ///< Valid for expressions.
44     } s;
45     const Value *Const;     ///< Valid for constants.
46     unsigned FrameIx;       ///< Valid for stack objects.
47     unsigned VReg;          ///< Valid for registers.
48   } u;
49   DIVariable *Var;
50   DIExpression *Expr;
51   DebugLoc DL;
52   unsigned Order;
53   enum DbgValueKind kind;
54   bool IsIndirect;
55   bool Invalid = false;
56   bool Emitted = false;
57 
58 public:
59   /// Constructor for non-constants.
60   SDDbgValue(DIVariable *Var, DIExpression *Expr, SDNode *N, unsigned R,
61              bool indir, DebugLoc dl, unsigned O)
62       : Var(Var), Expr(Expr), DL(std::move(dl)), Order(O), IsIndirect(indir) {
63     kind = SDNODE;
64     u.s.Node = N;
65     u.s.ResNo = R;
66   }
67 
68   /// Constructor for constants.
69   SDDbgValue(DIVariable *Var, DIExpression *Expr, const Value *C, DebugLoc dl,
70              unsigned O)
71       : Var(Var), Expr(Expr), DL(std::move(dl)), Order(O), IsIndirect(false) {
72     kind = CONST;
73     u.Const = C;
74   }
75 
76   /// Constructor for virtual registers and frame indices.
77   SDDbgValue(DIVariable *Var, DIExpression *Expr, unsigned VRegOrFrameIdx,
78              bool IsIndirect, DebugLoc DL, unsigned Order,
79              enum DbgValueKind Kind)
80       : Var(Var), Expr(Expr), DL(DL), Order(Order), IsIndirect(IsIndirect) {
81     assert((Kind == VREG || Kind == FRAMEIX) &&
82            "Invalid SDDbgValue constructor");
83     kind = Kind;
84     if (kind == VREG)
85       u.VReg = VRegOrFrameIdx;
86     else
87       u.FrameIx = VRegOrFrameIdx;
88   }
89 
90   /// Returns the kind.
91   DbgValueKind getKind() const { return kind; }
92 
93   /// Returns the DIVariable pointer for the variable.
94   DIVariable *getVariable() const { return Var; }
95 
96   /// Returns the DIExpression pointer for the expression.
97   DIExpression *getExpression() const { return Expr; }
98 
99   /// Returns the SDNode* for a register ref
100   SDNode *getSDNode() const { assert (kind==SDNODE); return u.s.Node; }
101 
102   /// Returns the ResNo for a register ref
103   unsigned getResNo() const { assert (kind==SDNODE); return u.s.ResNo; }
104 
105   /// Returns the Value* for a constant
106   const Value *getConst() const { assert (kind==CONST); return u.Const; }
107 
108   /// Returns the FrameIx for a stack object
109   unsigned getFrameIx() const { assert (kind==FRAMEIX); return u.FrameIx; }
110 
111   /// Returns the Virtual Register for a VReg
112   unsigned getVReg() const { assert (kind==VREG); return u.VReg; }
113 
114   /// Returns whether this is an indirect value.
115   bool isIndirect() const { return IsIndirect; }
116 
117   /// Returns the DebugLoc.
118   DebugLoc getDebugLoc() const { return DL; }
119 
120   /// Returns the SDNodeOrder.  This is the order of the preceding node in the
121   /// input.
122   unsigned getOrder() const { return Order; }
123 
124   /// setIsInvalidated / isInvalidated - Setter / getter of the "Invalidated"
125   /// property. A SDDbgValue is invalid if the SDNode that produces the value is
126   /// deleted.
127   void setIsInvalidated() { Invalid = true; }
128   bool isInvalidated() const { return Invalid; }
129 
130   /// setIsEmitted / isEmitted - Getter/Setter for flag indicating that this
131   /// SDDbgValue has been emitted to an MBB.
132   void setIsEmitted() { Emitted = true; }
133   bool isEmitted() const { return Emitted; }
134 
135   /// clearIsEmitted - Reset Emitted flag, for certain special cases where
136   /// dbg.addr is emitted twice.
137   void clearIsEmitted() { Emitted = false; }
138 
139   LLVM_DUMP_METHOD void dump(raw_ostream &OS) const;
140 };
141 
142 /// Holds the information from a dbg_label node through SDISel.
143 /// We do not use SDValue here to avoid including its header.
144 class SDDbgLabel {
145   MDNode *Label;
146   DebugLoc DL;
147   unsigned Order;
148 
149 public:
150   SDDbgLabel(MDNode *Label, DebugLoc dl, unsigned O)
151       : Label(Label), DL(std::move(dl)), Order(O) {}
152 
153   /// Returns the MDNode pointer for the label.
154   MDNode *getLabel() const { return Label; }
155 
156   /// Returns the DebugLoc.
157   DebugLoc getDebugLoc() const { return DL; }
158 
159   /// Returns the SDNodeOrder.  This is the order of the preceding node in the
160   /// input.
161   unsigned getOrder() const { return Order; }
162 };
163 
164 } // end llvm namespace
165 
166 #endif
167