1314564Sdim//===------ Core/Pass.h - Base class for linker passes ----------*- C++ -*-===// 2280461Sdim// 3353358Sdim// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4353358Sdim// See https://llvm.org/LICENSE.txt for license information. 5353358Sdim// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6280461Sdim// 7280461Sdim//===----------------------------------------------------------------------===// 8280461Sdim 9280461Sdim#ifndef LLD_CORE_PASS_H 10280461Sdim#define LLD_CORE_PASS_H 11280461Sdim 12303239Sdim#include "llvm/Support/Error.h" 13280461Sdim 14280461Sdimnamespace lld { 15314564Sdim 16292934Sdimclass SimpleFile; 17280461Sdim 18280461Sdim/// Once the core linking is done (which resolves references, coalesces atoms 19280461Sdim/// and produces a complete Atom graph), the linker runs a series of passes 20280461Sdim/// on the Atom graph. The graph is modeled as a File, which means the pass 21280461Sdim/// has access to all the atoms and to File level attributes. Each pass does 22280461Sdim/// a particular transformation to the Atom graph or to the File attributes. 23280461Sdim/// 24280461Sdim/// This is the abstract base class for all passes. A Pass does its 25280461Sdim/// actual work in it perform() method. It can iterator over Atoms in the 26280461Sdim/// graph using the *begin()/*end() atom iterator of the File. It can add 27280461Sdim/// new Atoms to the graph using the File's addAtom() method. 28280461Sdimclass Pass { 29280461Sdimpublic: 30314564Sdim virtual ~Pass() = default; 31280461Sdim 32280461Sdim /// Do the actual work of the Pass. 33303239Sdim virtual llvm::Error perform(SimpleFile &mergedFile) = 0; 34280461Sdim 35280461Sdimprotected: 36280461Sdim // Only subclassess can be instantiated. 37314564Sdim Pass() = default; 38280461Sdim}; 39280461Sdim 40314564Sdim} // end namespace lld 41280461Sdim 42280461Sdim#endif // LLD_CORE_PASS_H 43