3837f4273f
This patch is mechanically generated by clang-llvm-rename tool that I wrote using Clang Refactoring Engine just for creating this patch. You can see the source code of the tool at https://reviews.llvm.org/D64123. There's no manual post-processing; you can generate the same patch by re-running the tool against lld's code base. Here is the main discussion thread to change the LLVM coding style: https://lists.llvm.org/pipermail/llvm-dev/2019-February/130083.html In the discussion thread, I proposed we use lld as a testbed for variable naming scheme change, and this patch does that. I chose to rename variables so that they are in camelCase, just because that is a minimal change to make variables to start with a lowercase letter. Note to downstream patch maintainers: if you are maintaining a downstream lld repo, just rebasing ahead of this commit would cause massive merge conflicts because this patch essentially changes every line in the lld subdirectory. But there's a remedy. clang-llvm-rename tool is a batch tool, so you can rename variables in your downstream repo with the tool. Given that, here is how to rebase your repo to a commit after the mass renaming: 1. rebase to the commit just before the mass variable renaming, 2. apply the tool to your downstream repo to mass-rename variables locally, and 3. rebase again to the head. Most changes made by the tool should be identical for a downstream repo and for the head, so at the step 3, almost all changes should be merged and disappear. I'd expect that there would be some lines that you need to merge by hand, but that shouldn't be too many. Differential Revision: https://reviews.llvm.org/D64121 llvm-svn: 365595
74 lines
2.5 KiB
C++
74 lines
2.5 KiB
C++
//===- Thunks.h --------------------------------------------------------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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#ifndef LLD_ELF_THUNKS_H
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#define LLD_ELF_THUNKS_H
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#include "Relocations.h"
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namespace lld {
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namespace elf {
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class Defined;
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class Symbol;
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class ThunkSection;
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// Class to describe an instance of a Thunk.
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// A Thunk is a code-sequence inserted by the linker in between a caller and
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// the callee. The relocation to the callee is redirected to the Thunk, which
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// after executing transfers control to the callee. Typical uses of Thunks
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// include transferring control from non-pi to pi and changing state on
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// targets like ARM.
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//
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// Thunks can be created for Defined, Shared and Undefined Symbols.
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// Thunks are assigned to synthetic ThunkSections
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class Thunk {
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public:
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Thunk(Symbol &destination);
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virtual ~Thunk();
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virtual uint32_t size() = 0;
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virtual void writeTo(uint8_t *buf) = 0;
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// All Thunks must define at least one symbol, known as the thunk target
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// symbol, so that we can redirect relocations to it. The thunk may define
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// additional symbols, but these are never targets for relocations.
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virtual void addSymbols(ThunkSection &isec) = 0;
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void setOffset(uint64_t offset);
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Defined *addSymbol(StringRef name, uint8_t type, uint64_t value,
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InputSectionBase §ion);
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// Some Thunks must be placed immediately before their Target as they elide
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// a branch and fall through to the first Symbol in the Target.
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virtual InputSection *getTargetInputSection() const { return nullptr; }
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// To reuse a Thunk the InputSection and the relocation must be compatible
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// with it.
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virtual bool isCompatibleWith(const InputSection &,
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const Relocation &) const {
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return true;
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}
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Defined *getThunkTargetSym() const { return syms[0]; }
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// The alignment requirement for this Thunk, defaults to the size of the
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// typical code section alignment.
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Symbol &destination;
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llvm::SmallVector<Defined *, 3> syms;
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uint64_t offset = 0;
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uint32_t alignment = 4;
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};
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// For a Relocation to symbol S create a Thunk to be added to a synthetic
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// ThunkSection.
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Thunk *addThunk(const InputSection &isec, Relocation &rel);
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} // namespace elf
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} // namespace lld
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#endif
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