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26 
27 #ifndef VIXL_ASSEMBLER_BASE_H
28 #define VIXL_ASSEMBLER_BASE_H
29 
30 #include "code-buffer-vixl.h"
31 
32 namespace vixl {
33 
34 class CodeBufferCheckScope;
35 
36 namespace internal {
37 
38 class AssemblerBase {
39  public:
AssemblerBase()40   AssemblerBase() : allow_assembler_(false) {}
AssemblerBase(size_t capacity)41   explicit AssemblerBase(size_t capacity)
42       : buffer_(capacity), allow_assembler_(false) {}
AssemblerBase(byte * buffer,size_t capacity)43   AssemblerBase(byte* buffer, size_t capacity)
44       : buffer_(buffer, capacity), allow_assembler_(false) {}
45 
~AssemblerBase()46   virtual ~AssemblerBase() {}
47 
48   // Finalize a code buffer of generated instructions. This function must be
49   // called before executing or copying code from the buffer.
FinalizeCode()50   void FinalizeCode() { GetBuffer()->SetClean(); }
51 
GetCursorOffset()52   ptrdiff_t GetCursorOffset() const { return GetBuffer().GetCursorOffset(); }
53 
54   // Return the address of the cursor.
55   template <typename T>
GetCursorAddress()56   T GetCursorAddress() const {
57     VIXL_STATIC_ASSERT(sizeof(T) >= sizeof(uintptr_t));
58     return GetBuffer().GetOffsetAddress<T>(GetCursorOffset());
59   }
60 
GetSizeOfCodeGenerated()61   size_t GetSizeOfCodeGenerated() const { return GetCursorOffset(); }
62 
63   // Accessors.
GetBuffer()64   CodeBuffer* GetBuffer() { return &buffer_; }
GetBuffer()65   const CodeBuffer& GetBuffer() const { return buffer_; }
AllowAssembler()66   bool AllowAssembler() const { return allow_assembler_; }
67 
68  protected:
SetAllowAssembler(bool allow)69   void SetAllowAssembler(bool allow) { allow_assembler_ = allow; }
70 
71   // CodeBufferCheckScope must be able to temporarily allow the assembler.
72   friend class vixl::CodeBufferCheckScope;
73 
74   // Buffer where the code is emitted.
75   CodeBuffer buffer_;
76 
77  private:
78   bool allow_assembler_;
79 
80  public:
81   // Deprecated public interface.
82 
83   // Return the address of an offset in the buffer.
84   template <typename T>
85   VIXL_DEPRECATED("GetBuffer().GetOffsetAddress<T>(offset)",
86                   T GetOffsetAddress(ptrdiff_t offset) const) {
87     return GetBuffer().GetOffsetAddress<T>(offset);
88   }
89 
90   // Return the address of the start of the buffer.
91   template <typename T>
92   VIXL_DEPRECATED("GetBuffer().GetStartAddress<T>()",
93                   T GetStartAddress() const) {
94     return GetBuffer().GetOffsetAddress<T>(0);
95   }
96 };
97 
98 }  // namespace internal
99 }  // namespace vixl
100 
101 #endif  // VIXL_ASSEMBLER_BASE_H
102