1 //===-- llvm/CodeGen/SDNodeDbgValue.h - SelectionDAG dbg_value --*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file declares the SDDbgValue class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_CODEGEN_SELECTIONDAG_SDNODEDBGVALUE_H
14 #define LLVM_LIB_CODEGEN_SELECTIONDAG_SDNODEDBGVALUE_H
15 
16 #include "llvm/IR/DebugLoc.h"
17 #include "llvm/Support/DataTypes.h"
18 #include <utility>
19 
20 namespace llvm {
21 
22 class DIVariable;
23 class DIExpression;
24 class SDNode;
25 class Value;
26 class raw_ostream;
27 
28 /// Holds the information from a dbg_value node through SDISel.
29 /// We do not use SDValue here to avoid including its header.
30 class SDDbgValue {
31 public:
32   enum DbgValueKind {
33     SDNODE = 0,             ///< Value is the result of an expression.
34     CONST = 1,              ///< Value is a constant.
35     FRAMEIX = 2,            ///< Value is contents of a stack location.
36     VREG = 3                ///< Value is a virtual register.
37   };
38 private:
39   union {
40     struct {
41       SDNode *Node;         ///< Valid for expressions.
42       unsigned ResNo;       ///< Valid for expressions.
43     } s;
44     const Value *Const;     ///< Valid for constants.
45     unsigned FrameIx;       ///< Valid for stack objects.
46     unsigned VReg;          ///< Valid for registers.
47   } u;
48   DIVariable *Var;
49   DIExpression *Expr;
50   DebugLoc DL;
51   unsigned Order;
52   enum DbgValueKind kind;
53   bool IsIndirect;
54   bool Invalid = false;
55   bool Emitted = false;
56 
57 public:
58   /// Constructor for non-constants.
59   SDDbgValue(DIVariable *Var, DIExpression *Expr, SDNode *N, unsigned R,
60              bool indir, DebugLoc dl, unsigned O)
61       : Var(Var), Expr(Expr), DL(std::move(dl)), Order(O), IsIndirect(indir) {
62     kind = SDNODE;
63     u.s.Node = N;
64     u.s.ResNo = R;
65   }
66 
67   /// Constructor for constants.
68   SDDbgValue(DIVariable *Var, DIExpression *Expr, const Value *C, DebugLoc dl,
69              unsigned O)
70       : Var(Var), Expr(Expr), DL(std::move(dl)), Order(O), IsIndirect(false) {
71     kind = CONST;
72     u.Const = C;
73   }
74 
75   /// Constructor for virtual registers and frame indices.
76   SDDbgValue(DIVariable *Var, DIExpression *Expr, unsigned VRegOrFrameIdx,
77              bool IsIndirect, DebugLoc DL, unsigned Order,
78              enum DbgValueKind Kind)
79       : Var(Var), Expr(Expr), DL(DL), Order(Order), IsIndirect(IsIndirect) {
80     assert((Kind == VREG || Kind == FRAMEIX) &&
81            "Invalid SDDbgValue constructor");
82     kind = Kind;
83     if (kind == VREG)
84       u.VReg = VRegOrFrameIdx;
85     else
86       u.FrameIx = VRegOrFrameIdx;
87   }
88 
89   /// Returns the kind.
90   DbgValueKind getKind() const { return kind; }
91 
92   /// Returns the DIVariable pointer for the variable.
93   DIVariable *getVariable() const { return Var; }
94 
95   /// Returns the DIExpression pointer for the expression.
96   DIExpression *getExpression() const { return Expr; }
97 
98   /// Returns the SDNode* for a register ref
99   SDNode *getSDNode() const { assert (kind==SDNODE); return u.s.Node; }
100 
101   /// Returns the ResNo for a register ref
102   unsigned getResNo() const { assert (kind==SDNODE); return u.s.ResNo; }
103 
104   /// Returns the Value* for a constant
105   const Value *getConst() const { assert (kind==CONST); return u.Const; }
106 
107   /// Returns the FrameIx for a stack object
108   unsigned getFrameIx() const { assert (kind==FRAMEIX); return u.FrameIx; }
109 
110   /// Returns the Virtual Register for a VReg
111   unsigned getVReg() const { assert (kind==VREG); return u.VReg; }
112 
113   /// Returns whether this is an indirect value.
114   bool isIndirect() const { return IsIndirect; }
115 
116   /// Returns the DebugLoc.
117   DebugLoc getDebugLoc() const { return DL; }
118 
119   /// Returns the SDNodeOrder.  This is the order of the preceding node in the
120   /// input.
121   unsigned getOrder() const { return Order; }
122 
123   /// setIsInvalidated / isInvalidated - Setter / getter of the "Invalidated"
124   /// property. A SDDbgValue is invalid if the SDNode that produces the value is
125   /// deleted.
126   void setIsInvalidated() { Invalid = true; }
127   bool isInvalidated() const { return Invalid; }
128 
129   /// setIsEmitted / isEmitted - Getter/Setter for flag indicating that this
130   /// SDDbgValue has been emitted to an MBB.
131   void setIsEmitted() { Emitted = true; }
132   bool isEmitted() const { return Emitted; }
133 
134   /// clearIsEmitted - Reset Emitted flag, for certain special cases where
135   /// dbg.addr is emitted twice.
136   void clearIsEmitted() { Emitted = false; }
137 
138   LLVM_DUMP_METHOD void dump() const;
139   LLVM_DUMP_METHOD void print(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