1 //===-- DWARFFormValue.h ----------------------------------------*- 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 #ifndef LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFFORMVALUE_H
10 #define LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFFORMVALUE_H
11 
12 #include "DWARFDataExtractor.h"
13 #include <cstddef>
14 #include <optional>
15 
16 class DWARFUnit;
17 class SymbolFileDWARF;
18 class DWARFDIE;
19 
20 class DWARFFormValue {
21 public:
22   typedef struct ValueTypeTag {
23     ValueTypeTag() : value() { value.uval = 0; }
24 
25     union {
26       uint64_t uval;
27       int64_t sval;
28       const char *cstr;
29     } value;
30     const uint8_t *data = nullptr;
31   } ValueType;
32 
33   enum {
34     eValueTypeInvalid = 0,
35     eValueTypeUnsigned,
36     eValueTypeSigned,
37     eValueTypeCStr,
38     eValueTypeBlock
39   };
40 
41   DWARFFormValue() = default;
42   DWARFFormValue(const DWARFUnit *unit) : m_unit(unit) {}
43   DWARFFormValue(const DWARFUnit *unit, dw_form_t form)
44       : m_unit(unit), m_form(form) {}
45   const DWARFUnit *GetUnit() const { return m_unit; }
46   void SetUnit(const DWARFUnit *unit) { m_unit = unit; }
47   dw_form_t Form() const { return m_form; }
48   dw_form_t& FormRef() { return m_form; }
49   void SetForm(dw_form_t form) { m_form = form; }
50   const ValueType &Value() const { return m_value; }
51   ValueType &ValueRef() { return m_value; }
52   void SetValue(const ValueType &val) { m_value = val; }
53 
54   void Dump(lldb_private::Stream &s) const;
55   bool ExtractValue(const lldb_private::DWARFDataExtractor &data,
56                     lldb::offset_t *offset_ptr);
57   const uint8_t *BlockData() const;
58   static std::optional<uint8_t> GetFixedSize(dw_form_t form,
59                                              const DWARFUnit *u);
60   std::optional<uint8_t> GetFixedSize() const;
61   DWARFDIE Reference() const;
62   uint64_t Reference(dw_offset_t offset) const;
63   bool Boolean() const { return m_value.value.uval != 0; }
64   uint64_t Unsigned() const { return m_value.value.uval; }
65   void SetUnsigned(uint64_t uval) { m_value.value.uval = uval; }
66   int64_t Signed() const { return m_value.value.sval; }
67   void SetSigned(int64_t sval) { m_value.value.sval = sval; }
68   const char *AsCString() const;
69   dw_addr_t Address() const;
70   bool IsValid() const { return m_form != 0; }
71   bool SkipValue(const lldb_private::DWARFDataExtractor &debug_info_data,
72                  lldb::offset_t *offset_ptr) const;
73   static bool SkipValue(const dw_form_t form,
74                         const lldb_private::DWARFDataExtractor &debug_info_data,
75                         lldb::offset_t *offset_ptr, const DWARFUnit *unit);
76   static bool IsBlockForm(const dw_form_t form);
77   static bool IsDataForm(const dw_form_t form);
78   static int Compare(const DWARFFormValue &a, const DWARFFormValue &b);
79   void Clear();
80   static bool FormIsSupported(dw_form_t form);
81 
82 protected:
83   // Compile unit where m_value was located.
84   // It may be different from compile unit where m_value refers to.
85   const DWARFUnit *m_unit = nullptr; // Unit for this form
86   dw_form_t m_form = 0;              // Form for this value
87   ValueType m_value;            // Contains all data for the form
88 };
89 
90 #endif // LLDB_SOURCE_PLUGINS_SYMBOLFILE_DWARF_DWARFFORMVALUE_H
91