#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalValue.h"
#include "llvm/IR/GlobalVariable.h"
-#include "llvm/IR/Mangler.h"
#include "llvm/IR/Module.h"
#include "llvm/MC/MCAsmInfo.h"
#include "llvm/MC/MCContext.h"
});
}
-// Ensure ELF .symver aliases get the same binding as the defined symbol
-// they alias with.
-static void handleSymverAliases(const Module &M, RecordStreamer &Streamer) {
- if (Streamer.symverAliases().empty())
- return;
-
- // The name in the assembler will be mangled, but the name in the IR
- // might not, so we first compute a mapping from mangled name to GV.
- Mangler Mang;
- SmallString<64> MangledName;
- StringMap<const GlobalValue *> MangledNameMap;
- auto GetMangledName = [&](const GlobalValue &GV) {
- if (!GV.hasName())
- return;
-
- MangledName.clear();
- MangledName.reserve(GV.getName().size() + 1);
- Mang.getNameWithPrefix(MangledName, &GV, /*CannotUsePrivateLabel=*/false);
- MangledNameMap[MangledName] = &GV;
- };
- for (const Function &F : M)
- GetMangledName(F);
- for (const GlobalVariable &GV : M.globals())
- GetMangledName(GV);
- for (const GlobalAlias &GA : M.aliases())
- GetMangledName(GA);
-
- // Walk all the recorded .symver aliases, and set up the binding
- // for each alias.
- for (auto &Symver : Streamer.symverAliases()) {
- const MCSymbol *Aliasee = Symver.first;
- MCSymbolAttr Attr = MCSA_Invalid;
-
- // First check if the aliasee binding was recorded in the asm.
- RecordStreamer::State state = Streamer.getSymbolState(Aliasee);
- switch (state) {
- case RecordStreamer::Global:
- case RecordStreamer::DefinedGlobal:
- Attr = MCSA_Global;
- break;
- case RecordStreamer::UndefinedWeak:
- case RecordStreamer::DefinedWeak:
- Attr = MCSA_Weak;
- break;
- default:
- break;
- }
-
- // If we don't have a symbol attribute from assembly, then check if
- // the aliasee was defined in the IR.
- if (Attr == MCSA_Invalid) {
- const auto *GV = M.getNamedValue(Aliasee->getName());
- if (!GV) {
- auto MI = MangledNameMap.find(Aliasee->getName());
- if (MI != MangledNameMap.end())
- GV = MI->second;
- else
- continue;
- }
- if (GV->hasExternalLinkage())
- Attr = MCSA_Global;
- else if (GV->hasLocalLinkage())
- Attr = MCSA_Local;
- else if (GV->isWeakForLinker())
- Attr = MCSA_Weak;
- }
- if (Attr == MCSA_Invalid)
- continue;
-
- // Set the detected binding on each alias with this aliasee.
- for (auto &Alias : Symver.second)
- Streamer.EmitSymbolAttribute(Alias, Attr);
- }
-}
-
void ModuleSymbolTable::CollectAsmSymbols(
const Module &M,
function_ref<void(StringRef, BasicSymbolRef::Flags)> AsmSymbol) {
MCObjectFileInfo MOFI;
MCContext MCCtx(MAI.get(), MRI.get(), &MOFI);
MOFI.InitMCObjectFileInfo(TT, /*PIC*/ false, MCCtx);
- RecordStreamer Streamer(MCCtx);
+ RecordStreamer Streamer(MCCtx, M);
T->createNullTargetStreamer(Streamer);
std::unique_ptr<MemoryBuffer> Buffer(MemoryBuffer::getMemBuffer(InlineAsm));
if (Parser->Run(false))
return;
- handleSymverAliases(M, Streamer);
+ Streamer.flushSymverDirectives();
for (auto &KV : Streamer) {
StringRef Key = KV.first();
//===----------------------------------------------------------------------===//
#include "RecordStreamer.h"
+#include "llvm/IR/Mangler.h"
+#include "llvm/IR/Module.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCSymbol.h"
void RecordStreamer::visitUsedSymbol(const MCSymbol &Sym) { markUsed(Sym); }
-RecordStreamer::RecordStreamer(MCContext &Context) : MCStreamer(Context) {}
+RecordStreamer::RecordStreamer(MCContext &Context, const Module &M)
+ : MCStreamer(Context), M(M) {}
RecordStreamer::const_iterator RecordStreamer::begin() {
return Symbols.begin();
markDefined(*Symbol);
}
+RecordStreamer::State RecordStreamer::getSymbolState(const MCSymbol *Sym) {
+ auto SI = Symbols.find(Sym->getName());
+ if (SI == Symbols.end())
+ return NeverSeen;
+ return SI->second;
+}
+
void RecordStreamer::emitELFSymverDirective(StringRef AliasName,
const MCSymbol *Aliasee) {
- MCSymbol *Alias = getContext().getOrCreateSymbol(AliasName);
- const MCExpr *Value = MCSymbolRefExpr::create(Aliasee, getContext());
- EmitAssignment(Alias, Value);
- SymverAliasMap[Aliasee].push_back(Alias);
+ SymverAliasMap[Aliasee].push_back(AliasName);
+}
+
+void RecordStreamer::flushSymverDirectives() {
+ // Mapping from mangled name to GV.
+ StringMap<const GlobalValue *> MangledNameMap;
+ // The name in the assembler will be mangled, but the name in the IR
+ // might not, so we first compute a mapping from mangled name to GV.
+ Mangler Mang;
+ SmallString<64> MangledName;
+ for (const GlobalValue &GV : M.global_values()) {
+ if (!GV.hasName())
+ continue;
+ MangledName.clear();
+ MangledName.reserve(GV.getName().size() + 1);
+ Mang.getNameWithPrefix(MangledName, &GV, /*CannotUsePrivateLabel=*/false);
+ MangledNameMap[MangledName] = &GV;
+ }
+
+ // Walk all the recorded .symver aliases, and set up the binding
+ // for each alias.
+ for (auto &Symver : SymverAliasMap) {
+ const MCSymbol *Aliasee = Symver.first;
+ MCSymbolAttr Attr = MCSA_Invalid;
+
+ // First check if the aliasee binding was recorded in the asm.
+ RecordStreamer::State state = getSymbolState(Aliasee);
+ switch (state) {
+ case RecordStreamer::Global:
+ case RecordStreamer::DefinedGlobal:
+ Attr = MCSA_Global;
+ break;
+ case RecordStreamer::UndefinedWeak:
+ case RecordStreamer::DefinedWeak:
+ Attr = MCSA_Weak;
+ break;
+ default:
+ break;
+ }
+
+ // If we don't have a symbol attribute from assembly, then check if
+ // the aliasee was defined in the IR.
+ if (Attr == MCSA_Invalid) {
+ const auto *GV = M.getNamedValue(Aliasee->getName());
+ if (!GV) {
+ auto MI = MangledNameMap.find(Aliasee->getName());
+ if (MI != MangledNameMap.end())
+ GV = MI->second;
+ }
+ if (GV) {
+ if (GV->hasExternalLinkage())
+ Attr = MCSA_Global;
+ else if (GV->hasLocalLinkage())
+ Attr = MCSA_Local;
+ else if (GV->isWeakForLinker())
+ Attr = MCSA_Weak;
+ }
+ }
+ // Set the detected binding on each alias with this aliasee.
+ for (auto AliasName : Symver.second) {
+ MCSymbol *Alias = getContext().getOrCreateSymbol(AliasName);
+ // TODO: Handle "@@@". Depending on SymbolAttribute value it needs to be
+ // converted into @ or @@.
+ const MCExpr *Value = MCSymbolRefExpr::create(Aliasee, getContext());
+ EmitAssignment(Alias, Value);
+ if (Attr != MCSA_Invalid)
+ EmitSymbolAttribute(Alias, Attr);
+ }
+ }
}
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<MCSymbol *>> SymverAliasMap;
+ 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 visitUsedSymbol(const MCSymbol &Sym) override;
public:
- RecordStreamer(MCContext &Context);
+ RecordStreamer(MCContext &Context, const Module &M);
using const_iterator = StringMap<State>::const_iterator;
/// Record .symver aliases for later processing.
void emitELFSymverDirective(StringRef AliasName,
const MCSymbol *Aliasee) override;
- /// Return the map of .symver aliasee to associated aliases.
- DenseMap<const MCSymbol *, std::vector<MCSymbol *>> &symverAliases() {
- return SymverAliasMap;
- }
-
- /// Get the state recorded for the given symbol.
- State getSymbolState(const MCSymbol *Sym) {
- auto SI = Symbols.find(Sym->getName());
- if (SI == Symbols.end())
- return NeverSeen;
- return SI->second;
- }
+ // Emit ELF .symver aliases and ensure they have the same binding as the
+ // defined symbol they alias with.
+ void flushSymverDirectives();
};
} // end namespace llvm