Theodosius/Examples/Theodosius-Usermode/asmjit/core/jitruntime.h

// AsmJit - Machine code generation for C++
//
//  * Official AsmJit Home Page: https://asmjit.com
//  * Official Github Repository: https://github.com/asmjit/asmjit
//
// Copyright (c) 2008-2020 The AsmJit Authors
//
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// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
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// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would be
//    appreciated but is not required.
// 2. Altered source versions must be plainly marked as such, and must not be
//    misrepresented as being the original software.
// 3. This notice may not be removed or altered from any source distribution.

#ifndef ASMJIT_CORE_JITRUNTIME_H_INCLUDED
#define ASMJIT_CORE_JITRUNTIME_H_INCLUDED

#include "../core/api-config.h"
#ifndef ASMJIT_NO_JIT

#include "../core/codeholder.h"
#include "../core/jitallocator.h"
#include "../core/target.h"

ASMJIT_BEGIN_NAMESPACE

class CodeHolder;

//! \addtogroup asmjit_virtual_memory
//! \{

// ============================================================================
// [asmjit::JitRuntime]
// ============================================================================

//! JIT execution runtime is a special `Target` that is designed to store and
//! execute the generated code.
class ASMJIT_VIRTAPI JitRuntime : public Target {
public:
  ASMJIT_NONCOPYABLE(JitRuntime)

  //! Virtual memory allocator.
  JitAllocator _allocator;

  //! \name Construction & Destruction
  //! \{

  //! Creates a `JitRuntime` instance.
  explicit ASMJIT_API JitRuntime(const JitAllocator::CreateParams* params = nullptr) noexcept;
  //! Destroys the `JitRuntime` instance.
  ASMJIT_API virtual ~JitRuntime() noexcept;

  inline void reset(uint32_t resetPolicy = Globals::kResetSoft) noexcept {
    _allocator.reset(resetPolicy);
  }

  //! \}

  //! \name Accessors
  //! \{

  //! Returns the associated `JitAllocator`.
  inline JitAllocator* allocator() const noexcept { return const_cast<JitAllocator*>(&_allocator); }

  //! \}

  //! \name Utilities
  //! \{

  // NOTE: To allow passing function pointers to `add()` and `release()` the
  // virtual methods are prefixed with `_` and called from templates instead.

  //! Allocates memory needed for a code stored in the `CodeHolder` and relocates
  //! the code to the pointer allocated.
  //!
  //! The beginning of the memory allocated for the function is returned in `dst`.
  //! If failed `Error` code is returned and `dst` is explicitly set to `nullptr`
  //! (this means that you don't have to set it to null before calling `add()`).
  template<typename Func>
  inline Error add(Func* dst, CodeHolder* code) noexcept {
    return _add(Support::ptr_cast_impl<void**, Func*>(dst), code);
  }

  //! Releases `p` which was obtained by calling `add()`.
  template<typename Func>
  inline Error release(Func p) noexcept {
    return _release(Support::ptr_cast_impl<void*, Func>(p));
  }

  //! Type-unsafe version of `add()`.
  ASMJIT_API virtual Error _add(void** dst, CodeHolder* code) noexcept;

  //! Type-unsafe version of `release()`.
  ASMJIT_API virtual Error _release(void* p) noexcept;

  //! Flushes an instruction cache.
  //!
  //! This member function is called after the code has been copied to the
  //! destination buffer. It is only useful for JIT code generation as it
  //! causes a flush of the processor's cache.
  //!
  //! Flushing is basically a NOP under X86, but is needed by architectures
  //! that do not have a transparent instruction cache like ARM.
  //!
  //! This function can also be overridden to improve compatibility with tools
  //! such as Valgrind, however, it's not an official part of AsmJit.
  ASMJIT_API virtual void flush(const void* p, size_t size) noexcept;

  //! \}
};

//! \}

ASMJIT_END_NAMESPACE

#endif
#endif