#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/JumpInstrTableInfo.h"
#include "llvm/CodeGen/GCMetadataPrinter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
}
AsmPrinter::~AsmPrinter() {
- assert(DD == 0 && Handlers.empty() && "Debug/EH info didn't get finalized");
+ assert(!DD && Handlers.empty() && "Debug/EH info didn't get finalized");
if (GCMetadataPrinters) {
gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
OutStreamer.AddBlankLine();
}
+static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP);
+
bool AsmPrinter::doFinalization(Module &M) {
// Emit global variables.
for (const auto &G : M.globals())
EmitVisibility(Name, V, false);
}
+ // Get information about jump-instruction tables to print.
+ JumpInstrTableInfo *JITI = getAnalysisIfAvailable<JumpInstrTableInfo>();
+
+ if (JITI && !JITI->getTables().empty()) {
+ unsigned Arch = Triple(getTargetTriple()).getArch();
+ bool IsThumb = (Arch == Triple::thumb || Arch == Triple::thumbeb);
+ MCInst TrapInst;
+ TM.getInstrInfo()->getTrap(TrapInst);
+ for (const auto &KV : JITI->getTables()) {
+ uint64_t Count = 0;
+ for (const auto &FunPair : KV.second) {
+ // Emit the function labels to make this be a function entry point.
+ MCSymbol *FunSym =
+ OutContext.GetOrCreateSymbol(FunPair.second->getName());
+ OutStreamer.EmitSymbolAttribute(FunSym, MCSA_Global);
+ // FIXME: JumpTableInstrInfo should store information about the required
+ // alignment of table entries and the size of the padding instruction.
+ EmitAlignment(3);
+ if (IsThumb)
+ OutStreamer.EmitThumbFunc(FunSym);
+ if (MAI->hasDotTypeDotSizeDirective())
+ OutStreamer.EmitSymbolAttribute(FunSym, MCSA_ELF_TypeFunction);
+ OutStreamer.EmitLabel(FunSym);
+
+ // Emit the jump instruction to transfer control to the original
+ // function.
+ MCInst JumpToFun;
+ MCSymbol *TargetSymbol =
+ OutContext.GetOrCreateSymbol(FunPair.first->getName());
+ const MCSymbolRefExpr *TargetSymRef =
+ MCSymbolRefExpr::Create(TargetSymbol, MCSymbolRefExpr::VK_PLT,
+ OutContext);
+ TM.getInstrInfo()->getUnconditionalBranch(JumpToFun, TargetSymRef);
+ OutStreamer.EmitInstruction(JumpToFun, getSubtargetInfo());
+ ++Count;
+ }
+
+ // Emit enough padding instructions to fill up to the next power of two.
+ // This assumes that the trap instruction takes 8 bytes or fewer.
+ uint64_t Remaining = NextPowerOf2(Count) - Count;
+ for (uint64_t C = 0; C < Remaining; ++C) {
+ EmitAlignment(3);
+ OutStreamer.EmitInstruction(TrapInst, getSubtargetInfo());
+ }
+
+ }
+ }
+
// Emit module flags.
SmallVector<Module::ModuleFlagEntry, 8> ModuleFlags;
M.getModuleFlagsMetadata(ModuleFlags);
for (const auto &Alias : M.aliases()) {
MCSymbol *Name = getSymbol(&Alias);
- const GlobalValue *GV = Alias.getAliasedGlobal();
- assert(!GV->isDeclaration());
- MCSymbol *Target = getSymbol(GV);
-
if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
// Emit the directives as assignments aka .set:
OutStreamer.EmitAssignment(Name,
- MCSymbolRefExpr::Create(Target, OutContext));
+ lowerConstant(Alias.getAliasee(), *this));
}
}
}
// Ignore debug and non-emitted data. This handles llvm.compiler.used.
- if (GV->getSection() == "llvm.metadata" ||
+ if (StringRef(GV->getSection()) == "llvm.metadata" ||
GV->hasAvailableExternallyLinkage())
return true;
}
}
+namespace {
+struct Structor {
+ Structor() : Priority(0), Func(nullptr), ComdatKey(nullptr) {}
+ int Priority;
+ llvm::Constant *Func;
+ llvm::GlobalValue *ComdatKey;
+};
+} // end namespace
+
/// EmitXXStructorList - Emit the ctor or dtor list taking into account the init
/// priority.
void AsmPrinter::EmitXXStructorList(const Constant *List, bool isCtor) {
const ConstantArray *InitList = dyn_cast<ConstantArray>(List);
if (!InitList) return; // Not an array!
StructType *ETy = dyn_cast<StructType>(InitList->getType()->getElementType());
- if (!ETy || ETy->getNumElements() != 2) return; // Not an array of pairs!
+ // FIXME: Only allow the 3-field form in LLVM 4.0.
+ if (!ETy || ETy->getNumElements() < 2 || ETy->getNumElements() > 3)
+ return; // Not an array of two or three elements!
if (!isa<IntegerType>(ETy->getTypeAtIndex(0U)) ||
!isa<PointerType>(ETy->getTypeAtIndex(1U))) return; // Not (int, ptr).
+ if (ETy->getNumElements() == 3 && !isa<PointerType>(ETy->getTypeAtIndex(2U)))
+ return; // Not (int, ptr, ptr).
// Gather the structors in a form that's convenient for sorting by priority.
- typedef std::pair<unsigned, Constant *> Structor;
SmallVector<Structor, 8> Structors;
- for (unsigned i = 0, e = InitList->getNumOperands(); i != e; ++i) {
- ConstantStruct *CS = dyn_cast<ConstantStruct>(InitList->getOperand(i));
+ for (Value *O : InitList->operands()) {
+ ConstantStruct *CS = dyn_cast<ConstantStruct>(O);
if (!CS) continue; // Malformed.
if (CS->getOperand(1)->isNullValue())
break; // Found a null terminator, skip the rest.
ConstantInt *Priority = dyn_cast<ConstantInt>(CS->getOperand(0));
if (!Priority) continue; // Malformed.
- Structors.push_back(std::make_pair(Priority->getLimitedValue(65535),
- CS->getOperand(1)));
+ Structors.push_back(Structor());
+ Structor &S = Structors.back();
+ S.Priority = Priority->getLimitedValue(65535);
+ S.Func = CS->getOperand(1);
+ if (ETy->getNumElements() == 3 && !CS->getOperand(2)->isNullValue())
+ S.ComdatKey = dyn_cast<GlobalValue>(CS->getOperand(2)->stripPointerCasts());
}
// Emit the function pointers in the target-specific order
const DataLayout *DL = TM.getDataLayout();
unsigned Align = Log2_32(DL->getPointerPrefAlignment());
- std::stable_sort(Structors.begin(), Structors.end(), less_first());
- for (unsigned i = 0, e = Structors.size(); i != e; ++i) {
+ std::stable_sort(Structors.begin(), Structors.end(),
+ [](const Structor &L,
+ const Structor &R) { return L.Priority < R.Priority; });
+ for (Structor &S : Structors) {
+ const TargetLoweringObjectFile &Obj = getObjFileLowering();
+ const MCSymbol *KeySym = nullptr;
+ const MCSection *KeySec = nullptr;
+ if (GlobalValue *GV = S.ComdatKey) {
+ if (GV->hasAvailableExternallyLinkage())
+ // If the associated variable is available_externally, some other TU
+ // will provide its dynamic initializer.
+ continue;
+
+ KeySym = getSymbol(GV);
+ KeySec = getObjFileLowering().SectionForGlobal(GV, *Mang, TM);
+ }
const MCSection *OutputSection =
- (isCtor ?
- getObjFileLowering().getStaticCtorSection(Structors[i].first) :
- getObjFileLowering().getStaticDtorSection(Structors[i].first));
+ (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym, KeySec)
+ : Obj.getStaticDtorSection(S.Priority, KeySym, KeySec));
OutStreamer.SwitchSection(OutputSection);
if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
EmitAlignment(Align);
- EmitXXStructor(Structors[i].second);
+ EmitXXStructor(S.Func);
}
}
// an explicit alignment requested, it will override the alignment request
// if required for correctness.
//
-void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalValue *GV) const {
+void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.