llvm-project/llvm/lib/Object/RecordStreamer.h

87 lines
3.1 KiB
C++

//===- RecordStreamer.h - Record asm defined and used symbols ---*- 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
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_OBJECT_RECORDSTREAMER_H
#define LLVM_LIB_OBJECT_RECORDSTREAMER_H
#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/MC/MCDirectives.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
#include "llvm/Support/SMLoc.h"
#include <vector>
namespace llvm {
class GlobalValue;
class Module;
class RecordStreamer : public MCStreamer {
public:
enum State { NeverSeen, Global, Defined, DefinedGlobal, DefinedWeak, Used,
UndefinedWeak};
private:
const Module &M;
StringMap<State> Symbols;
// Map of aliases created by .symver directives, saved so we can update
// their symbol binding after parsing complete. This maps from each
// aliasee to its list of aliases.
DenseMap<const MCSymbol *, std::vector<StringRef>> SymverAliasMap;
/// Get the state recorded for the given symbol.
State getSymbolState(const MCSymbol *Sym);
void markDefined(const MCSymbol &Symbol);
void markGlobal(const MCSymbol &Symbol, MCSymbolAttr Attribute);
void markUsed(const MCSymbol &Symbol);
void visitUsedSymbol(const MCSymbol &Sym) override;
public:
RecordStreamer(MCContext &Context, const Module &M);
void EmitInstruction(const MCInst &Inst, const MCSubtargetInfo &STI) override;
void EmitLabel(MCSymbol *Symbol, SMLoc Loc = SMLoc()) override;
void EmitAssignment(MCSymbol *Symbol, const MCExpr *Value) override;
bool EmitSymbolAttribute(MCSymbol *Symbol, MCSymbolAttr Attribute) override;
void EmitZerofill(MCSection *Section, MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment, SMLoc Loc = SMLoc()) override;
void EmitCommonSymbol(MCSymbol *Symbol, uint64_t Size,
unsigned ByteAlignment) override;
// Ignore COFF-specific directives; we do not need any information from them,
// but the default implementation of these methods crashes, so we override
// them with versions that do nothing.
void BeginCOFFSymbolDef(const MCSymbol *Symbol) override {}
void EmitCOFFSymbolStorageClass(int StorageClass) override {}
void EmitCOFFSymbolType(int Type) override {}
void EndCOFFSymbolDef() override {}
/// Record .symver aliases for later processing.
void emitELFSymverDirective(StringRef AliasName,
const MCSymbol *Aliasee) override;
// Emit ELF .symver aliases and ensure they have the same binding as the
// defined symbol they alias with.
void flushSymverDirectives();
// Symbols iterators
using const_iterator = StringMap<State>::const_iterator;
const_iterator begin();
const_iterator end();
// SymverAliasMap iterators
using const_symver_iterator = decltype(SymverAliasMap)::const_iterator;
iterator_range<const_symver_iterator> symverAliases();
};
} // end namespace llvm
#endif // LLVM_LIB_OBJECT_RECORDSTREAMER_H