teak-llvm/llvm/lib/Object/RecordStreamer.h
Bob Haarman 38ebaf7d5d allow COFF .def directive in module assembly when using ThinLTO
Summary:
Using COFF's .def directive in module assembly used to crash ThinLTO
with "this directive only supported on COFF targets" when getting
symbol information in ModuleSymbolTable.  This change allows
ModuleSymbolTable to process such code and adds a test to verify that
the .def directive has the desired effect on the native object file,
with and without ThinLTO.

Fixes https://bugs.llvm.org/show_bug.cgi?id=36789

Reviewers: rnk, pcc, vlad.tsyrklevich

Subscribers: mehdi_amini, eraman, hiraditya, dexonsmith, llvm-commits

Differential Revision: https://reviews.llvm.org/D57073

llvm-svn: 352112
2019-01-24 21:41:03 +00:00

88 lines
3.2 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,
bool) 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