text: /*
     +----------------------------------------------------------------------+
     | HipHop for PHP                                                       |
     +----------------------------------------------------------------------+
     | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
     +----------------------------------------------------------------------+
     | This source file is subject to version 3.01 of the PHP license,      |
     | that is bundled with this package in the file LICENSE, and is        |
     | available through the world-wide-web at the following url:           |
     | http://www.php.net/license/3_01.txt                                  |
     | If you did not receive a copy of the PHP license and are unable to   |
     | obtain it through the world-wide-web, please send a note to          |
     | license@php.net so we can mail you a copy immediately.               |
     +----------------------------------------------------------------------+
  */
  
  #pragma once
  
  #include "hphp/runtime/vm/jit/vasm.h"
  
  namespace HPHP::jit {
  
  ///////////////////////////////////////////////////////////////////////////////
  
  struct Vunit;
  
  /*
   * Vasm-to-vasm lowering state.
   */
  struct VLS {
    Vunit& unit;
    int vreg_restrict_level;
  
    bool allow_vreg() const {
      return vreg_restrict_level >= 0;
    }
  };
  
  ///////////////////////////////////////////////////////////////////////////////
  
  /*
   * Toplevel vasm-to-vasm lowering pass.
   *
   * The `lower_impl' callback should have the signature:
   *
   *    void lower_impl(const VLS& env, Vinstr& inst, Vlabel b, size_t i);
   *
   * where `b' and `i' are the block and code index of `inst' in `unit'.  This
   * callback is responsible for any architecture-specific lowering that is
   * needed for `inst'.
   */
  template<class Vlower>
  void vasm_lower(Vunit& unit, Vlower lower_impl);
  
  /*
   * Lower a single instruction.
   *
   * Replaces the instruction at `unit.blocks[b].code[i]` with an appropriate
   * sequence of one or more instructions.
   */
  void vlower(VLS& env, Vlabel b, size_t i);
  
  ///////////////////////////////////////////////////////////////////////////////
  
  }
  
  #include "hphp/runtime/vm/jit/vasm-lower-inl.h"
  
  