trampoline.h

//===-- include/flang/Runtime/trampoline.h ----------------------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// Runtime support for W^X-compliant trampoline pool management.
//
// This provides an alternative to stack-based trampolines for internal
// procedures with host association. Instead of requiring the stack to be
// both writable and executable (violating W^X security policies), this
// implementation uses a pool of trampoline stubs generated during pool
// initialization in a separate executable (but not writable) memory region,
// paired with writable (but not executable) data entries.
//
// See flang/docs/InternalProcedureTrampolines.md for design details.
//
//===----------------------------------------------------------------------===//
 
#ifndef FORTRAN_RUNTIME_TRAMPOLINE_H_
#define FORTRAN_RUNTIME_TRAMPOLINE_H_
 
#include "flang/Runtime/entry-names.h"
 
namespace Fortran::runtime {
extern "C" {

void *RTDECL(TrampolineInit)(
    void *scratch, const void *calleeAddress, const void *staticChainAddress);

void *RTDECL(TrampolineAdjust)(void *handle);

void RTDECL(TrampolineFree)(void *handle);
 
} // extern "C"
} // namespace Fortran::runtime
 
#endif // FORTRAN_RUNTIME_TRAMPOLINE_H_