1 //===-- DWARFFormValue.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 SymbolFileDWARF_DWARFFormValue_h_
11 #define SymbolFileDWARF_DWARFFormValue_h_
12 
13 #include "DWARFDataExtractor.h"
14 #include <stddef.h> // for NULL
15 
16 class DWARFCompileUnit;
17 
18 class DWARFFormValue {
19 public:
20   typedef struct ValueTypeTag {
21     ValueTypeTag() : value(), data(NULL) { value.uval = 0; }
22 
23     union {
24       uint64_t uval;
25       int64_t sval;
26       const char *cstr;
27     } value;
28     const uint8_t *data;
29   } ValueType;
30 
31   class FixedFormSizes {
32   public:
33     FixedFormSizes() : m_fix_sizes(nullptr), m_size(0) {}
34 
35     FixedFormSizes(const uint8_t *fix_sizes, size_t size)
36         : m_fix_sizes(fix_sizes), m_size(size) {}
37 
38     uint8_t GetSize(uint32_t index) const {
39       return index < m_size ? m_fix_sizes[index] : 0;
40     }
41 
42     bool Empty() const { return m_size == 0; }
43 
44   private:
45     const uint8_t *m_fix_sizes;
46     size_t m_size;
47   };
48 
49   enum {
50     eValueTypeInvalid = 0,
51     eValueTypeUnsigned,
52     eValueTypeSigned,
53     eValueTypeCStr,
54     eValueTypeBlock
55   };
56 
57   DWARFFormValue();
58   DWARFFormValue(const DWARFCompileUnit *cu, dw_form_t form);
59   const DWARFCompileUnit *GetCompileUnit() const { return m_cu; }
60   void SetCompileUnit(const DWARFCompileUnit *cu) { m_cu = cu; }
61   dw_form_t Form() const { return m_form; }
62   void SetForm(dw_form_t form) { m_form = form; }
63   const ValueType &Value() const { return m_value; }
64   void Dump(lldb_private::Stream &s) const;
65   bool ExtractValue(const lldb_private::DWARFDataExtractor &data,
66                     lldb::offset_t *offset_ptr);
67   const uint8_t *BlockData() const;
68   uint64_t Reference() const;
69   uint64_t Reference(dw_offset_t offset) const;
70   bool Boolean() const { return m_value.value.uval != 0; }
71   uint64_t Unsigned() const { return m_value.value.uval; }
72   void SetUnsigned(uint64_t uval) { m_value.value.uval = uval; }
73   int64_t Signed() const { return m_value.value.sval; }
74   void SetSigned(int64_t sval) { m_value.value.sval = sval; }
75   const char *AsCString() const;
76   dw_addr_t Address() const;
77   bool IsValid() const { return m_form != 0; }
78   bool SkipValue(const lldb_private::DWARFDataExtractor &debug_info_data,
79                  lldb::offset_t *offset_ptr) const;
80   static bool SkipValue(const dw_form_t form,
81                         const lldb_private::DWARFDataExtractor &debug_info_data,
82                         lldb::offset_t *offset_ptr, const DWARFCompileUnit *cu);
83   static bool IsBlockForm(const dw_form_t form);
84   static bool IsDataForm(const dw_form_t form);
85   static FixedFormSizes GetFixedFormSizesForAddressSize(uint8_t addr_size,
86                                                         bool is_dwarf64);
87   static int Compare(const DWARFFormValue &a, const DWARFFormValue &b);
88   void Clear();
89 
90 protected:
91   const DWARFCompileUnit *m_cu; // Compile unit for this form
92   dw_form_t m_form;             // Form for this value
93   ValueType m_value;            // Contains all data for the form
94 };
95 
96 #endif // SymbolFileDWARF_DWARFFormValue_h_
97