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26 
27 #include <iostream>
28 #include <map>
29 #include <string>
30 
31 #include "aarch32/constants-aarch32.h"
32 #include "aarch32/disasm-aarch32.h"
33 #include "aarch32/instructions-aarch32.h"
34 #include "aarch32/macro-assembler-aarch32.h"
35 
36 #define __ masm.
37 
38 namespace vixl {
39 namespace aarch32 {
40 
41 // Example of disassembly customization.
42 
43 class CustomStream : public Disassembler::DisassemblerStream {
44   std::map<Location::Offset, const char*> symbols_;
45 
46  public:
47   CustomStream() : Disassembler::DisassemblerStream(std::cout) {}
48   std::map<Location::Offset, const char*>& GetSymbols() { return symbols_; }
49   virtual DisassemblerStream& operator<<(const Disassembler::PrintLabel& label)
50       VIXL_OVERRIDE {
51     std::map<Location::Offset, const char*>::iterator symbol =
52         symbols_.find(label.GetLocation());
53     // If the label was named, print the name instead of the address.
54     if (symbol != symbols_.end()) {
55       os() << symbol->second;
56       return *this;
57     }
58     os() << label;
59     return *this;
60   }
61   virtual DisassemblerStream& operator<<(const Register reg) VIXL_OVERRIDE {
62     // Print all the core registers with an upper-case letter instead of the
63     // default lower-case.
64     os() << "R" << reg.GetCode();
65     return *this;
66   }
67 };
68 
69 class CustomDisassembler : public PrintDisassembler {
70  public:
71   explicit CustomDisassembler(CustomStream* stream)
72       : PrintDisassembler(stream) {}
73   CustomStream* GetStream() const {
74     return reinterpret_cast<CustomStream*>(&os());
75   }
76   virtual void PrintCodeAddress(uint32_t pc) VIXL_OVERRIDE {
77     // If the address matches a label, then print the label. Otherwise, print
78     // nothing.
79     std::map<Location::Offset, const char*>::iterator symbol =
80         GetStream()->GetSymbols().find(pc);
81     if (symbol != GetStream()->GetSymbols().end()) {
82       os().os() << symbol->second << ":" << std::endl;
83     }
84     // Add indentation for instructions.
85     os() << "  ";
86   }
87   virtual void PrintOpcode16(uint32_t opcode) VIXL_OVERRIDE {
88     // Do not print opcodes.
89     USE(opcode);
90   }
91   virtual void PrintOpcode32(uint32_t opcode) VIXL_OVERRIDE {
92     // Do not print opcodes.
93     USE(opcode);
94   }
95 };
96 
97 class NamedLabel : public Label {
98   CustomStream* stream_;
99   const char* name_;
100 
101  public:
102   NamedLabel(CustomStream* stream, const char* name)
103       : stream_(stream), name_(name) {}
104   ~NamedLabel() VIXL_THROW_IN_NEGATIVE_TESTING_MODE(std::runtime_error) {
105     if (IsBound()) {
106       stream_->GetSymbols().insert(
107           std::pair<Location::Offset, const char*>(GetLocation(), name_));
108     }
109   }
110 };
111 
112 void RunCustomDisassemblerTest() {
113   CustomStream stream;
114   MacroAssembler masm;
115   {
116     NamedLabel loop(&stream, "loop");
117     NamedLabel end(&stream, "end");
118     __ Mov(r0, 0);
119     __ Mov(r1, 0);
120     __ Bind(&loop);
121     __ Cmp(r1, 20);
122     __ B(gt, &end);
123     __ Add(r0, r0, r1);
124     __ Add(r1, r1, 1);
125     __ B(&loop);
126     __ Bind(&end);
127     __ Bx(lr);
128     __ FinalizeCode();
129   }
130   std::cout << "Custom disassembly:" << std::endl;
131   CustomDisassembler custom_disassembler(&stream);
132   custom_disassembler
133       .DisassembleA32Buffer(masm.GetBuffer()->GetOffsetAddress<uint32_t*>(0),
134                             masm.GetBuffer()->GetSizeInBytes());
135   std::cout << std::endl;
136   std::cout << "Standard disassembly:" << std::endl;
137   PrintDisassembler print_disassembler(std::cout);
138   print_disassembler
139       .DisassembleA32Buffer(masm.GetBuffer()->GetOffsetAddress<uint32_t*>(0),
140                             masm.GetBuffer()->GetSizeInBytes());
141 }
142 
143 }  // namespace aarch32
144 }  // namespace vixl
145 
146 #ifndef TEST_EXAMPLES
147 int main() {
148   vixl::aarch32::RunCustomDisassemblerTest();
149   return 0;
150 }
151 #endif  // TEST_EXAMPLES
152