llvm/lld/MachO/MarkLive.cpp

//===- MarkLive.cpp -------------------------------------------------------===//
//
// 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
//
//===----------------------------------------------------------------------===//

#include "MarkLive.h"
#include "Config.h"
#include "OutputSegment.h"
#include "SymbolTable.h"
#include "Symbols.h"
#include "UnwindInfoSection.h"

#include "lld/Common/ErrorHandler.h"
#include "llvm/Support/TimeProfiler.h"

#include "mach-o/compact_unwind_encoding.h"

namespace lld::macho {

usingnamespacellvm;
usingnamespacellvm::MachO;

struct WhyLiveEntry { … };

// Type-erased interface to MarkLiveImpl. Used for adding roots to the liveness
// graph.
class MarkLive { … };

template <bool RecordWhyLive> class MarkLiveImpl : public MarkLive { … };

template <bool RecordWhyLive>
void MarkLiveImpl<RecordWhyLive>::enqueue(
    InputSection *isec, uint64_t off,
    const typename MarkLiveImpl<RecordWhyLive>::WorklistEntry *prev) { … }

static void printWhyLive(const Symbol *s, const WhyLiveEntry *prev) { … }

template <bool RecordWhyLive>
void MarkLiveImpl<RecordWhyLive>::addSym(
    Symbol *s,
    const typename MarkLiveImpl<RecordWhyLive>::WorklistEntry *prev) { … }

template <bool RecordWhyLive>
const InputSection *MarkLiveImpl<RecordWhyLive>::getInputSection(
    const MarkLiveImpl<RecordWhyLive>::WorklistEntry *entry) const { … }

template <bool RecordWhyLive>
typename MarkLiveImpl<RecordWhyLive>::WorklistEntry *
MarkLiveImpl<RecordWhyLive>::makeEntry(
    InputSection *isec,
    const MarkLiveImpl<RecordWhyLive>::WorklistEntry *prev) const { … }

template <bool RecordWhyLive>
void MarkLiveImpl<RecordWhyLive>::markTransitively() { … }

// Set live bit on for each reachable chunk. Unmarked (unreachable)
// InputSections will be ignored by Writer, so they will be excluded
// from the final output.
void markLive() { … }

} // namespace lld::macho