src/macro-assembler-interface.h

// Copyright 2016, VIXL authors
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#ifndef VIXL_MACRO_ASSEMBLER_INTERFACE_H
#define VIXL_MACRO_ASSEMBLER_INTERFACE_H

#include "assembler-base-vixl.h"

namespace vixl {

class MacroAssemblerInterface {
 public:
  virtual internal::AssemblerBase* AsAssemblerBase() = 0;

  virtual ~MacroAssemblerInterface() VIXL_NEGATIVE_TESTING_ALLOW_EXCEPTION {}

  virtual bool AllowMacroInstructions() const = 0;
  virtual bool ArePoolsBlocked() const = 0;

 protected:
  virtual void SetAllowMacroInstructions(bool allow) = 0;

  virtual void BlockPools() = 0;
  virtual void ReleasePools() = 0;
  virtual void EnsureEmitPoolsFor(size_t size) = 0;

  // Emit the branch over a literal/veneer pool, and any necessary padding
  // before it.
  virtual void EmitPoolHeader() = 0;
  // When this is called, the label used for branching over the pool is bound.
  // This can also generate additional padding, which must correspond to the
  // alignment_ value passed to the PoolManager (which needs to keep track of
  // the exact size of the generated pool).
  virtual void EmitPoolFooter() = 0;

  // Emit n bytes of padding that does not have to be executable.
  virtual void EmitPaddingBytes(int n) = 0;
  // Emit n bytes of padding that has to be executable. Implementations must
  // make sure this is a multiple of the instruction size.
  virtual void EmitNopBytes(int n) = 0;

  // The following scopes need access to the above method in order to implement
  // pool blocking and temporarily disable the macro-assembler.
  friend class ExactAssemblyScope;
  friend class EmissionCheckScope;
  template <typename T>
  friend class PoolManager;
};

}  // namespace vixl

#endif  // VIXL_MACRO_ASSEMBLER_INTERFACE_H