#include "llvm/CodeGen/AsmPrinter.h"
#include "DwarfDebug.h"
#include "DwarfException.h"
+#include "Win64Exception.h"
#include "WinCodeViewLineTables.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/ConstantFolding.h"
+#include "llvm/Analysis/JumpInstrTableInfo.h"
+#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/GCMetadataPrinter.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/MC/MCSection.h"
#include "llvm/MC/MCStreamer.h"
#include "llvm/MC/MCSymbol.h"
+#include "llvm/MC/MCValue.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/Format.h"
#include "llvm/Support/MathExtras.h"
+#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/Timer.h"
#include "llvm/Target/TargetFrameLowering.h"
#include "llvm/Target/TargetInstrInfo.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Target/TargetLoweringObjectFile.h"
-#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/Target/TargetSubtargetInfo.h"
-#include "llvm/Transforms/Utils/GlobalStatus.h"
using namespace llvm;
#define DEBUG_TYPE "asm-printer"
/// getGVAlignmentLog2 - Return the alignment to use for the specified global
/// value in log2 form. This rounds up to the preferred alignment if possible
/// and legal.
-static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &TD,
+static unsigned getGVAlignmentLog2(const GlobalValue *GV, const DataLayout &DL,
unsigned InBits = 0) {
unsigned NumBits = 0;
if (const GlobalVariable *GVar = dyn_cast<GlobalVariable>(GV))
- NumBits = TD.getPreferredAlignmentLog(GVar);
+ NumBits = DL.getPreferredAlignmentLog(GVar);
// If InBits is specified, round it to it.
if (InBits > NumBits)
return NumBits;
}
-AsmPrinter::AsmPrinter(TargetMachine &tm, MCStreamer &Streamer)
- : MachineFunctionPass(ID),
- TM(tm), MAI(tm.getMCAsmInfo()), MII(tm.getInstrInfo()),
- OutContext(Streamer.getContext()),
- OutStreamer(Streamer),
- LastMI(nullptr), LastFn(0), Counter(~0U), SetCounter(0) {
- DD = nullptr; MMI = nullptr; LI = nullptr; MF = nullptr;
- CurrentFnSym = CurrentFnSymForSize = nullptr;
+AsmPrinter::AsmPrinter(TargetMachine &tm, std::unique_ptr<MCStreamer> Streamer)
+ : MachineFunctionPass(ID), TM(tm), MAI(tm.getMCAsmInfo()),
+ OutContext(Streamer->getContext()), OutStreamer(*Streamer.release()),
+ LastMI(nullptr), LastFn(0), Counter(~0U) {
+ DD = nullptr;
+ MMI = nullptr;
+ LI = nullptr;
+ MF = nullptr;
+ CurExceptionSym = CurrentFnSym = CurrentFnSymForSize = nullptr;
+ CurrentFnBegin = nullptr;
+ CurrentFnEnd = nullptr;
GCMetadataPrinters = nullptr;
- VerboseAsm = Streamer.isVerboseAsm();
+ VerboseAsm = OutStreamer.isVerboseAsm();
}
AsmPrinter::~AsmPrinter() {
}
const TargetLoweringObjectFile &AsmPrinter::getObjFileLowering() const {
- return TM.getTargetLowering()->getObjFileLowering();
+ return *TM.getObjFileLowering();
}
/// getDataLayout - Return information about data layout.
}
const MCSubtargetInfo &AsmPrinter::getSubtargetInfo() const {
- return TM.getSubtarget<MCSubtargetInfo>();
+ assert(MF && "getSubtargetInfo requires a valid MachineFunction!");
+ return MF->getSubtarget<MCSubtargetInfo>();
}
void AsmPrinter::EmitToStreamer(MCStreamer &S, const MCInst &Inst) {
const_cast<TargetLoweringObjectFile&>(getObjFileLowering())
.Initialize(OutContext, TM);
- OutStreamer.InitSections();
+ OutStreamer.InitSections(false);
Mang = new Mangler(TM.getDataLayout());
assert(MI && "AsmPrinter didn't require GCModuleInfo?");
for (auto &I : *MI)
if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(*I))
- MP->beginAssembly(*this);
+ MP->beginAssembly(M, *MI, *this);
// Emit module-level inline asm if it exists.
if (!M.getModuleInlineAsm().empty()) {
+ // We're at the module level. Construct MCSubtarget from the default CPU
+ // and target triple.
+ std::unique_ptr<MCSubtargetInfo> STI(TM.getTarget().createMCSubtargetInfo(
+ TM.getTargetTriple(), TM.getTargetCPU(), TM.getTargetFeatureString()));
OutStreamer.AddComment("Start of file scope inline assembly");
OutStreamer.AddBlankLine();
- EmitInlineAsm(M.getModuleInlineAsm()+"\n");
+ EmitInlineAsm(M.getModuleInlineAsm()+"\n", *STI);
OutStreamer.AddComment("End of file scope inline assembly");
OutStreamer.AddBlankLine();
}
if (MAI->doesSupportDebugInformation()) {
+ bool skip_dwarf = false;
if (Triple(TM.getTargetTriple()).isKnownWindowsMSVCEnvironment()) {
Handlers.push_back(HandlerInfo(new WinCodeViewLineTables(this),
DbgTimerName,
CodeViewLineTablesGroupName));
- } else {
+ // FIXME: Don't emit DWARF debug info if there's at least one function
+ // with AddressSanitizer instrumentation.
+ // This is a band-aid fix for PR22032.
+ for (auto &F : M.functions()) {
+ if (F.hasFnAttribute(Attribute::SanitizeAddress)) {
+ skip_dwarf = true;
+ break;
+ }
+ }
+ }
+ if (!skip_dwarf) {
DD = new DwarfDebug(this, &M);
Handlers.push_back(HandlerInfo(DD, DbgTimerName, DWARFGroupName));
}
}
- DwarfException *DE = nullptr;
+ EHStreamer *ES = nullptr;
switch (MAI->getExceptionHandlingType()) {
case ExceptionHandling::None:
break;
case ExceptionHandling::SjLj:
case ExceptionHandling::DwarfCFI:
- DE = new DwarfCFIException(this);
+ ES = new DwarfCFIException(this);
break;
case ExceptionHandling::ARM:
- DE = new ARMException(this);
+ ES = new ARMException(this);
break;
- case ExceptionHandling::Win64:
- DE = new Win64Exception(this);
+ case ExceptionHandling::WinEH:
+ switch (MAI->getWinEHEncodingType()) {
+ default: llvm_unreachable("unsupported unwinding information encoding");
+ case WinEH::EncodingType::Itanium:
+ ES = new Win64Exception(this);
+ break;
+ }
break;
}
- if (DE)
- Handlers.push_back(HandlerInfo(DE, EHTimerName, DWARFGroupName));
+ if (ES)
+ Handlers.push_back(HandlerInfo(ES, EHTimerName, DWARFGroupName));
return false;
}
static bool canBeHidden(const GlobalValue *GV, const MCAsmInfo &MAI) {
- GlobalValue::LinkageTypes Linkage = GV->getLinkage();
- if (Linkage != GlobalValue::LinkOnceODRLinkage)
- return false;
-
if (!MAI.hasWeakDefCanBeHiddenDirective())
return false;
- if (GV->hasUnnamedAddr())
- return true;
-
- // This is only used for MachO, so right now it doesn't really matter how
- // we handle alias. Revisit this once the MachO linker implements aliases.
- if (isa<GlobalAlias>(GV))
- return false;
-
- // If it is a non constant variable, it needs to be uniqued across shared
- // objects.
- if (const GlobalVariable *Var = dyn_cast<GlobalVariable>(GV)) {
- if (!Var->isConstant())
- return false;
- }
-
- GlobalStatus GS;
- if (!GlobalStatus::analyzeGlobal(GV, GS) && !GS.IsCompared)
- return true;
-
- return false;
+ return canBeOmittedFromSymbolTable(GV);
}
void AsmPrinter::EmitLinkage(const GlobalValue *GV, MCSymbol *GVSym) const {
if (EmitSpecialLLVMGlobal(GV))
return;
+ // Skip the emission of global equivalents. The symbol can be emitted later
+ // on by emitGlobalGOTEquivs in case it turns out to be needed.
+ if (GlobalGOTEquivs.count(getSymbol(GV)))
+ return;
+
if (isVerbose()) {
GV->printAsOperand(OutStreamer.GetCommentOS(),
/*PrintType=*/false, GV->getParent());
if (!GV->hasInitializer()) // External globals require no extra code.
return;
+ GVSym->redefineIfPossible();
+ if (GVSym->isDefined() || GVSym->isVariable())
+ report_fatal_error("symbol '" + Twine(GVSym->getName()) +
+ "' is already defined");
+
if (MAI->hasDotTypeDotSizeDirective())
OutStreamer.EmitSymbolAttribute(GVSym, MCSA_ELF_TypeObject);
EmitVisibility(CurrentFnSym, F->getVisibility());
EmitLinkage(F, CurrentFnSym);
- EmitAlignment(MF->getAlignment(), F);
+ if (MAI->hasFunctionAlignment())
+ EmitAlignment(MF->getAlignment(), F);
if (MAI->hasDotTypeDotSizeDirective())
OutStreamer.EmitSymbolAttribute(CurrentFnSym, MCSA_ELF_TypeFunction);
OutStreamer.GetCommentOS() << '\n';
}
+ // Emit the prefix data.
+ if (F->hasPrefixData())
+ EmitGlobalConstant(F->getPrefixData());
+
// Emit the CurrentFnSym. This is a virtual function to allow targets to
// do their wild and crazy things as required.
EmitFunctionEntryLabel();
OutStreamer.EmitLabel(DeadBlockSyms[i]);
}
+ if (CurrentFnBegin) {
+ if (MAI->useAssignmentForEHBegin()) {
+ MCSymbol *CurPos = OutContext.CreateTempSymbol();
+ OutStreamer.EmitLabel(CurPos);
+ OutStreamer.EmitAssignment(CurrentFnBegin,
+ MCSymbolRefExpr::Create(CurPos, OutContext));
+ } else {
+ OutStreamer.EmitLabel(CurrentFnBegin);
+ }
+ }
+
// Emit pre-function debug and/or EH information.
for (const HandlerInfo &HI : Handlers) {
NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
HI.Handler->beginFunction(MF);
}
- // Emit the prefix data.
- if (F->hasPrefixData())
- EmitGlobalConstant(F->getPrefixData());
+ // Emit the prologue data.
+ if (F->hasPrologueData())
+ EmitGlobalConstant(F->getPrologueData());
}
/// EmitFunctionEntryLabel - Emit the label that is the entrypoint for the
/// function. This can be overridden by targets as required to do custom stuff.
void AsmPrinter::EmitFunctionEntryLabel() {
+ CurrentFnSym->redefineIfPossible();
+
// The function label could have already been emitted if two symbols end up
// conflicting due to asm renaming. Detect this and emit an error.
- if (CurrentFnSym->isUndefined())
- return OutStreamer.EmitLabel(CurrentFnSym);
+ if (CurrentFnSym->isVariable())
+ report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
+ "' is a protected alias");
+ if (CurrentFnSym->isDefined())
+ report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
+ "' label emitted multiple times to assembly file");
- report_fatal_error("'" + Twine(CurrentFnSym->getName()) +
- "' label emitted multiple times to assembly file");
+ return OutStreamer.EmitLabel(CurrentFnSym);
}
/// emitComments - Pretty-print comments for instructions.
static void emitComments(const MachineInstr &MI, raw_ostream &CommentOS) {
const MachineFunction *MF = MI.getParent()->getParent();
- const TargetMachine &TM = MF->getTarget();
+ const TargetInstrInfo *TII = MF->getSubtarget().getInstrInfo();
// Check for spills and reloads
int FI;
// We assume a single instruction only has a spill or reload, not
// both.
const MachineMemOperand *MMO;
- if (TM.getInstrInfo()->isLoadFromStackSlotPostFE(&MI, FI)) {
+ if (TII->isLoadFromStackSlotPostFE(&MI, FI)) {
if (FrameInfo->isSpillSlotObjectIndex(FI)) {
MMO = *MI.memoperands_begin();
CommentOS << MMO->getSize() << "-byte Reload\n";
}
- } else if (TM.getInstrInfo()->hasLoadFromStackSlot(&MI, MMO, FI)) {
+ } else if (TII->hasLoadFromStackSlot(&MI, MMO, FI)) {
if (FrameInfo->isSpillSlotObjectIndex(FI))
CommentOS << MMO->getSize() << "-byte Folded Reload\n";
- } else if (TM.getInstrInfo()->isStoreToStackSlotPostFE(&MI, FI)) {
+ } else if (TII->isStoreToStackSlotPostFE(&MI, FI)) {
if (FrameInfo->isSpillSlotObjectIndex(FI)) {
MMO = *MI.memoperands_begin();
CommentOS << MMO->getSize() << "-byte Spill\n";
}
- } else if (TM.getInstrInfo()->hasStoreToStackSlot(&MI, MMO, FI)) {
+ } else if (TII->hasStoreToStackSlot(&MI, MMO, FI)) {
if (FrameInfo->isSpillSlotObjectIndex(FI))
CommentOS << MMO->getSize() << "-byte Folded Spill\n";
}
void AsmPrinter::emitImplicitDef(const MachineInstr *MI) const {
unsigned RegNo = MI->getOperand(0).getReg();
OutStreamer.AddComment(Twine("implicit-def: ") +
- TM.getRegisterInfo()->getName(RegNo));
+ MMI->getContext().getRegisterInfo()->getName(RegNo));
OutStreamer.AddBlankLine();
}
const MachineOperand &Op = MI->getOperand(i);
assert(Op.isReg() && "KILL instruction must have only register operands");
Str += ' ';
- Str += AP.TM.getRegisterInfo()->getName(Op.getReg());
+ Str += AP.MMI->getContext().getRegisterInfo()->getName(Op.getReg());
Str += (Op.isDef() ? "<def>" : "<kill>");
}
AP.OutStreamer.AddComment(Str);
/// of DBG_VALUE, returning true if it was able to do so. A false return
/// means the target will need to handle MI in EmitInstruction.
static bool emitDebugValueComment(const MachineInstr *MI, AsmPrinter &AP) {
- // This code handles only the 3-operand target-independent form.
- if (MI->getNumOperands() != 3)
+ // This code handles only the 4-operand target-independent form.
+ if (MI->getNumOperands() != 4)
return false;
SmallString<128> Str;
raw_svector_ostream OS(Str);
OS << "DEBUG_VALUE: ";
- DIVariable V(MI->getOperand(2).getMetadata());
+ DIVariable V = MI->getDebugVariable();
if (V.getContext().isSubprogram()) {
StringRef Name = DISubprogram(V.getContext()).getDisplayName();
if (!Name.empty())
OS << Name << ":";
}
- OS << V.getName() << " <- ";
+ OS << V.getName();
+
+ DIExpression Expr = MI->getDebugExpression();
+ if (Expr.isBitPiece())
+ OS << " [bit_piece offset=" << Expr.getBitPieceOffset()
+ << " size=" << Expr.getBitPieceSize() << "]";
+ OS << " <- ";
// The second operand is only an offset if it's an immediate.
bool Deref = MI->getOperand(0).isReg() && MI->getOperand(1).isImm();
Reg = MI->getOperand(0).getReg();
} else {
assert(MI->getOperand(0).isFI() && "Unknown operand type");
- const TargetFrameLowering *TFI = AP.TM.getFrameLowering();
+ const TargetFrameLowering *TFI = AP.MF->getSubtarget().getFrameLowering();
Offset += TFI->getFrameIndexReference(*AP.MF,
MI->getOperand(0).getIndex(), Reg);
Deref = true;
}
if (Deref)
OS << '[';
- OS << AP.TM.getRegisterInfo()->getName(Reg);
+ OS << AP.MMI->getContext().getRegisterInfo()->getName(Reg);
}
if (Deref)
}
bool AsmPrinter::needsSEHMoves() {
- return MAI->getExceptionHandlingType() == ExceptionHandling::Win64 &&
- MF->getFunction()->needsUnwindTableEntry();
+ return MAI->usesWindowsCFI() && MF->getFunction()->needsUnwindTableEntry();
}
void AsmPrinter::emitCFIInstruction(const MachineInstr &MI) {
- ExceptionHandling::ExceptionsType ExceptionHandlingType =
- MAI->getExceptionHandlingType();
+ ExceptionHandling ExceptionHandlingType = MAI->getExceptionHandlingType();
if (ExceptionHandlingType != ExceptionHandling::DwarfCFI &&
ExceptionHandlingType != ExceptionHandling::ARM)
return;
if (needsCFIMoves() == CFI_M_None)
return;
- if (MMI->getCompactUnwindEncoding() != 0)
- OutStreamer.EmitCompactUnwindEncoding(MMI->getCompactUnwindEncoding());
-
const MachineModuleInfo &MMI = MF->getMMI();
const std::vector<MCCFIInstruction> &Instrs = MMI.getFrameInstructions();
unsigned CFIIndex = MI.getOperand(0).getCFIIndex();
emitCFIInstruction(CFI);
}
+void AsmPrinter::emitFrameAlloc(const MachineInstr &MI) {
+ // The operands are the MCSymbol and the frame offset of the allocation.
+ MCSymbol *FrameAllocSym = MI.getOperand(0).getMCSymbol();
+ int FrameOffset = MI.getOperand(1).getImm();
+
+ // Emit a symbol assignment.
+ OutStreamer.EmitAssignment(FrameAllocSym,
+ MCConstantExpr::Create(FrameOffset, OutContext));
+}
+
/// EmitFunctionBody - This method emits the body and trailer for a
/// function.
void AsmPrinter::EmitFunctionBody() {
+ EmitFunctionHeader();
+
// Emit target-specific gunk before the function body.
EmitFunctionBodyStart();
// Print out code for the function.
bool HasAnyRealCode = false;
- const MachineInstr *LastMI = nullptr;
for (auto &MBB : *MF) {
// Print a label for the basic block.
EmitBasicBlockStart(MBB);
for (auto &MI : MBB) {
- LastMI = &MI;
// Print the assembly for the instruction.
if (!MI.isPosition() && !MI.isImplicitDef() && !MI.isKill() &&
emitCFIInstruction(MI);
break;
+ case TargetOpcode::FRAME_ALLOC:
+ emitFrameAlloc(MI);
+ break;
+
case TargetOpcode::EH_LABEL:
case TargetOpcode::GC_LABEL:
OutStreamer.EmitLabel(MI.getOperand(0).getMCSymbol());
}
}
}
- }
- // If the last instruction was a prolog label, then we have a situation where
- // we emitted a prolog but no function body. This results in the ending prolog
- // label equaling the end of function label and an invalid "row" in the
- // FDE. We need to emit a noop in this situation so that the FDE's rows are
- // valid.
- bool RequiresNoop = LastMI && LastMI->isCFIInstruction();
+ EmitBasicBlockEnd(MBB);
+ }
// If the function is empty and the object file uses .subsections_via_symbols,
// then we need to emit *something* to the function body to prevent the
// labels from collapsing together. Just emit a noop.
- if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode) || RequiresNoop) {
+ if ((MAI->hasSubsectionsViaSymbols() && !HasAnyRealCode)) {
MCInst Noop;
- TM.getInstrInfo()->getNoopForMachoTarget(Noop);
- if (Noop.getOpcode()) {
- OutStreamer.AddComment("avoids zero-length function");
+ MF->getSubtarget().getInstrInfo()->getNoopForMachoTarget(Noop);
+ OutStreamer.AddComment("avoids zero-length function");
+
+ // Targets can opt-out of emitting the noop here by leaving the opcode
+ // unspecified.
+ if (Noop.getOpcode())
OutStreamer.EmitInstruction(Noop, getSubtargetInfo());
- } else // Target not mc-ized yet.
- OutStreamer.EmitRawText(StringRef("\tnop\n"));
}
const Function *F = MF->getFunction();
// Emit target-specific gunk after the function body.
EmitFunctionBodyEnd();
+ if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
+ MAI->hasDotTypeDotSizeDirective()) {
+ // Create a symbol for the end of function.
+ CurrentFnEnd = createTempSymbol("func_end");
+ OutStreamer.EmitLabel(CurrentFnEnd);
+ }
+
// If the target wants a .size directive for the size of the function, emit
// it.
if (MAI->hasDotTypeDotSizeDirective()) {
- // Create a symbol for the end of function, so we can get the size as
- // difference between the function label and the temp label.
- MCSymbol *FnEndLabel = OutContext.CreateTempSymbol();
- OutStreamer.EmitLabel(FnEndLabel);
-
+ // We can get the size as difference between the function label and the
+ // temp label.
const MCExpr *SizeExp =
- MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(FnEndLabel, OutContext),
+ MCBinaryExpr::CreateSub(MCSymbolRefExpr::Create(CurrentFnEnd, OutContext),
MCSymbolRefExpr::Create(CurrentFnSymForSize,
OutContext),
OutContext);
OutStreamer.EmitELFSize(CurrentFnSym, SizeExp);
}
- // Emit post-function debug and/or EH information.
for (const HandlerInfo &HI : Handlers) {
NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
- HI.Handler->endFunction(MF);
+ HI.Handler->markFunctionEnd();
}
- MMI->EndFunction();
// Print out jump tables referenced by the function.
EmitJumpTableInfo();
+ // Emit post-function debug and/or EH information.
+ for (const HandlerInfo &HI : Handlers) {
+ NamedRegionTimer T(HI.TimerName, HI.TimerGroupName, TimePassesIsEnabled);
+ HI.Handler->endFunction(MF);
+ }
+ MMI->EndFunction();
+
OutStreamer.AddBlankLine();
}
-static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP);
+/// \brief Compute the number of Global Variables that uses a Constant.
+static unsigned getNumGlobalVariableUses(const Constant *C) {
+ if (!C)
+ return 0;
+
+ if (isa<GlobalVariable>(C))
+ return 1;
+
+ unsigned NumUses = 0;
+ for (auto *CU : C->users())
+ NumUses += getNumGlobalVariableUses(dyn_cast<Constant>(CU));
+
+ return NumUses;
+}
+
+/// \brief Only consider global GOT equivalents if at least one user is a
+/// cstexpr inside an initializer of another global variables. Also, don't
+/// handle cstexpr inside instructions. During global variable emission,
+/// candidates are skipped and are emitted later in case at least one cstexpr
+/// isn't replaced by a PC relative GOT entry access.
+static bool isGOTEquivalentCandidate(const GlobalVariable *GV,
+ unsigned &NumGOTEquivUsers) {
+ // Global GOT equivalents are unnamed private globals with a constant
+ // pointer initializer to another global symbol. They must point to a
+ // GlobalVariable or Function, i.e., as GlobalValue.
+ if (!GV->hasUnnamedAddr() || !GV->hasInitializer() || !GV->isConstant() ||
+ !GV->isDiscardableIfUnused() || !dyn_cast<GlobalValue>(GV->getOperand(0)))
+ return false;
+
+ // To be a got equivalent, at least one of its users need to be a constant
+ // expression used by another global variable.
+ for (auto *U : GV->users())
+ NumGOTEquivUsers += getNumGlobalVariableUses(dyn_cast<Constant>(U));
+
+ return NumGOTEquivUsers > 0;
+}
+
+/// \brief Unnamed constant global variables solely contaning a pointer to
+/// another globals variable is equivalent to a GOT table entry; it contains the
+/// the address of another symbol. Optimize it and replace accesses to these
+/// "GOT equivalents" by using the GOT entry for the final global instead.
+/// Compute GOT equivalent candidates among all global variables to avoid
+/// emitting them if possible later on, after it use is replaced by a GOT entry
+/// access.
+void AsmPrinter::computeGlobalGOTEquivs(Module &M) {
+ if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
+ return;
+
+ for (const auto &G : M.globals()) {
+ unsigned NumGOTEquivUsers = 0;
+ if (!isGOTEquivalentCandidate(&G, NumGOTEquivUsers))
+ continue;
+
+ const MCSymbol *GOTEquivSym = getSymbol(&G);
+ GlobalGOTEquivs[GOTEquivSym] = std::make_pair(&G, NumGOTEquivUsers);
+ }
+}
+
+/// \brief Constant expressions using GOT equivalent globals may not be eligible
+/// for PC relative GOT entry conversion, in such cases we need to emit such
+/// globals we previously omitted in EmitGlobalVariable.
+void AsmPrinter::emitGlobalGOTEquivs() {
+ if (!getObjFileLowering().supportIndirectSymViaGOTPCRel())
+ return;
+
+ SmallVector<const GlobalVariable *, 8> FailedCandidates;
+ for (auto &I : GlobalGOTEquivs) {
+ const GlobalVariable *GV = I.second.first;
+ unsigned Cnt = I.second.second;
+ if (Cnt)
+ FailedCandidates.push_back(GV);
+ }
+ GlobalGOTEquivs.clear();
+
+ for (auto *GV : FailedCandidates)
+ EmitGlobalVariable(GV);
+}
bool AsmPrinter::doFinalization(Module &M) {
+ // Set the MachineFunction to nullptr so that we can catch attempted
+ // accesses to MF specific features at the module level and so that
+ // we can conditionalize accesses based on whether or not it is nullptr.
+ MF = nullptr;
+
+ // Gather all GOT equivalent globals in the module. We really need two
+ // passes over the globals: one to compute and another to avoid its emission
+ // in EmitGlobalVariable, otherwise we would not be able to handle cases
+ // where the got equivalent shows up before its use.
+ computeGlobalGOTEquivs(M);
+
// Emit global variables.
for (const auto &G : M.globals())
EmitGlobalVariable(&G);
+ // Emit remaining GOT equivalent globals.
+ emitGlobalGOTEquivs();
+
// Emit visibility info for declarations
for (const Function &F : M) {
if (!F.isDeclaration())
}
}
- if (MAI->hasSetDirective()) {
- OutStreamer.AddBlankLine();
- for (const auto &Alias : M.aliases()) {
- MCSymbol *Name = getSymbol(&Alias);
+ OutStreamer.AddBlankLine();
+ for (const auto &Alias : M.aliases()) {
+ MCSymbol *Name = getSymbol(&Alias);
- if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
- OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
- else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
- OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
- else
- assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
+ if (Alias.hasExternalLinkage() || !MAI->getWeakRefDirective())
+ OutStreamer.EmitSymbolAttribute(Name, MCSA_Global);
+ else if (Alias.hasWeakLinkage() || Alias.hasLinkOnceLinkage())
+ OutStreamer.EmitSymbolAttribute(Name, MCSA_WeakReference);
+ else
+ assert(Alias.hasLocalLinkage() && "Invalid alias linkage");
- EmitVisibility(Name, Alias.getVisibility());
+ EmitVisibility(Name, Alias.getVisibility());
- // Emit the directives as assignments aka .set:
- OutStreamer.EmitAssignment(Name,
- lowerConstant(Alias.getAliasee(), *this));
- }
+ // Emit the directives as assignments aka .set:
+ OutStreamer.EmitAssignment(Name, lowerConstant(Alias.getAliasee()));
}
GCModuleInfo *MI = getAnalysisIfAvailable<GCModuleInfo>();
assert(MI && "AsmPrinter didn't require GCModuleInfo?");
for (GCModuleInfo::iterator I = MI->end(), E = MI->begin(); I != E; )
if (GCMetadataPrinter *MP = GetOrCreateGCPrinter(**--I))
- MP->finishAssembly(*this);
+ MP->finishAssembly(M, *MI, *this);
// Emit llvm.ident metadata in an '.ident' directive.
EmitModuleIdents(M);
+ // Emit __morestack address if needed for indirect calls.
+ if (MMI->usesMorestackAddr()) {
+ const MCSection *ReadOnlySection =
+ getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly(),
+ /*C=*/nullptr);
+ OutStreamer.SwitchSection(ReadOnlySection);
+
+ MCSymbol *AddrSymbol =
+ OutContext.GetOrCreateSymbol(StringRef("__morestack_addr"));
+ OutStreamer.EmitLabel(AddrSymbol);
+
+ unsigned PtrSize = TM.getDataLayout()->getPointerSize(0);
+ OutStreamer.EmitSymbolValue(GetExternalSymbolSymbol("__morestack"),
+ PtrSize);
+ }
+
// If we don't have any trampolines, then we don't require stack memory
// to be executable. Some targets have a directive to declare this.
Function *InitTrampolineIntrinsic = M.getFunction("llvm.init.trampoline");
return false;
}
+MCSymbol *AsmPrinter::getCurExceptionSym() {
+ if (!CurExceptionSym)
+ CurExceptionSym = createTempSymbol("exception");
+ return CurExceptionSym;
+}
+
void AsmPrinter::SetupMachineFunction(MachineFunction &MF) {
this->MF = &MF;
// Get the function symbol.
CurrentFnSym = getSymbol(MF.getFunction());
CurrentFnSymForSize = CurrentFnSym;
+ CurrentFnBegin = nullptr;
+ CurExceptionSym = nullptr;
+ bool NeedsLocalForSize = MAI->needsLocalForSize();
+ if (!MMI->getLandingPads().empty() || MMI->hasDebugInfo() ||
+ NeedsLocalForSize) {
+ CurrentFnBegin = createTempSymbol("func_begin");
+ if (NeedsLocalForSize)
+ CurrentFnSymForSize = CurrentFnBegin;
+ }
if (isVerbose())
LI = &getAnalysis<MachineLoopInfo>();
const MachineConstantPoolEntry &CPE = CP[i];
unsigned Align = CPE.getAlignment();
- SectionKind Kind;
- switch (CPE.getRelocationInfo()) {
- default: llvm_unreachable("Unknown section kind");
- case 2: Kind = SectionKind::getReadOnlyWithRel(); break;
- case 1:
- Kind = SectionKind::getReadOnlyWithRelLocal();
- break;
- case 0:
- switch (TM.getDataLayout()->getTypeAllocSize(CPE.getType())) {
- case 4: Kind = SectionKind::getMergeableConst4(); break;
- case 8: Kind = SectionKind::getMergeableConst8(); break;
- case 16: Kind = SectionKind::getMergeableConst16();break;
- default: Kind = SectionKind::getMergeableConst(); break;
- }
- }
+ SectionKind Kind =
+ CPE.getSectionKind(TM.getDataLayout());
- const MCSection *S = getObjFileLowering().getSectionForConstant(Kind);
+ const Constant *C = nullptr;
+ if (!CPE.isMachineConstantPoolEntry())
+ C = CPE.Val.ConstVal;
+
+ const MCSection *S = getObjFileLowering().getSectionForConstant(Kind, C);
// The number of sections are small, just do a linear search from the
// last section to the first.
}
// Now print stuff into the calculated sections.
+ const MCSection *CurSection = nullptr;
+ unsigned Offset = 0;
for (unsigned i = 0, e = CPSections.size(); i != e; ++i) {
- OutStreamer.SwitchSection(CPSections[i].S);
- EmitAlignment(Log2_32(CPSections[i].Alignment));
-
- unsigned Offset = 0;
for (unsigned j = 0, ee = CPSections[i].CPEs.size(); j != ee; ++j) {
unsigned CPI = CPSections[i].CPEs[j];
+ MCSymbol *Sym = GetCPISymbol(CPI);
+ if (!Sym->isUndefined())
+ continue;
+
+ if (CurSection != CPSections[i].S) {
+ OutStreamer.SwitchSection(CPSections[i].S);
+ EmitAlignment(Log2_32(CPSections[i].Alignment));
+ CurSection = CPSections[i].S;
+ Offset = 0;
+ }
+
MachineConstantPoolEntry CPE = CP[CPI];
// Emit inter-object padding for alignment.
OutStreamer.EmitZeros(NewOffset - Offset);
Type *Ty = CPE.getType();
- Offset = NewOffset + TM.getDataLayout()->getTypeAllocSize(Ty);
- OutStreamer.EmitLabel(GetCPISymbol(CPI));
+ Offset = NewOffset +
+ TM.getDataLayout()->getTypeAllocSize(Ty);
+ OutStreamer.EmitLabel(Sym);
if (CPE.isMachineConstantPoolEntry())
EmitMachineConstantPoolValue(CPE.Val.MachineCPVal);
else
// Pick the directive to use to print the jump table entries, and switch to
// the appropriate section.
const Function *F = MF->getFunction();
- bool JTInDiffSection = false;
- if (// In PIC mode, we need to emit the jump table to the same section as the
- // function body itself, otherwise the label differences won't make sense.
- // FIXME: Need a better predicate for this: what about custom entries?
- MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 ||
- // We should also do if the section name is NULL or function is declared
- // in discardable section
- // FIXME: this isn't the right predicate, should be based on the MCSection
- // for the function.
- F->isWeakForLinker()) {
- OutStreamer.SwitchSection(
- getObjFileLowering().SectionForGlobal(F, *Mang, TM));
- } else {
- // Otherwise, drop it in the readonly section.
+ const TargetLoweringObjectFile &TLOF = getObjFileLowering();
+ bool JTInDiffSection = !TLOF.shouldPutJumpTableInFunctionSection(
+ MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32,
+ *F);
+ if (JTInDiffSection) {
+ // Drop it in the readonly section.
const MCSection *ReadOnlySection =
- getObjFileLowering().getSectionForConstant(SectionKind::getReadOnly());
+ TLOF.getSectionForJumpTable(*F, *Mang, TM);
OutStreamer.SwitchSection(ReadOnlySection);
- JTInDiffSection = true;
}
- EmitAlignment(Log2_32(MJTI->getEntryAlignment(*TM.getDataLayout())));
+ EmitAlignment(Log2_32(
+ MJTI->getEntryAlignment(*TM.getDataLayout())));
// Jump tables in code sections are marked with a data_region directive
// where that's supported.
// If this jump table was deleted, ignore it.
if (JTBBs.empty()) continue;
- // For the EK_LabelDifference32 entry, if the target supports .set, emit a
- // .set directive for each unique entry. This reduces the number of
- // relocations the assembler will generate for the jump table.
+ // For the EK_LabelDifference32 entry, if using .set avoids a relocation,
+ /// emit a .set directive for each unique entry.
if (MJTI->getEntryKind() == MachineJumpTableInfo::EK_LabelDifference32 &&
- MAI->hasSetDirective()) {
+ MAI->doesSetDirectiveSuppressesReloc()) {
SmallPtrSet<const MachineBasicBlock*, 16> EmittedSets;
- const TargetLowering *TLI = TM.getTargetLowering();
+ const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF,JTI,OutContext);
for (unsigned ii = 0, ee = JTBBs.size(); ii != ee; ++ii) {
const MachineBasicBlock *MBB = JTBBs[ii];
- if (!EmittedSets.insert(MBB)) continue;
+ if (!EmittedSets.insert(MBB).second)
+ continue;
// .set LJTSet, LBB32-base
const MCExpr *LHS =
case MachineJumpTableInfo::EK_Inline:
llvm_unreachable("Cannot emit EK_Inline jump table entry");
case MachineJumpTableInfo::EK_Custom32:
- Value = TM.getTargetLowering()->LowerCustomJumpTableEntry(MJTI, MBB, UID,
- OutContext);
+ Value = MF->getSubtarget().getTargetLowering()->LowerCustomJumpTableEntry(
+ MJTI, MBB, UID, OutContext);
break;
case MachineJumpTableInfo::EK_BlockAddress:
// EK_BlockAddress - Each entry is a plain address of block, e.g.:
}
case MachineJumpTableInfo::EK_LabelDifference32: {
- // EK_LabelDifference32 - Each entry is the address of the block minus
- // the address of the jump table. This is used for PIC jump tables where
- // gprel32 is not supported. e.g.:
+ // Each entry is the address of the block minus the address of the jump
+ // table. This is used for PIC jump tables where gprel32 is not supported.
+ // e.g.:
// .word LBB123 - LJTI1_2
- // If the .set directive is supported, this is emitted as:
+ // If the .set directive avoids relocations, this is emitted as:
// .set L4_5_set_123, LBB123 - LJTI1_2
// .word L4_5_set_123
-
- // If we have emitted set directives for the jump table entries, print
- // them rather than the entries themselves. If we're emitting PIC, then
- // emit the table entries as differences between two text section labels.
- if (MAI->hasSetDirective()) {
- // If we used .set, reference the .set's symbol.
+ if (MAI->doesSetDirectiveSuppressesReloc()) {
Value = MCSymbolRefExpr::Create(GetJTSetSymbol(UID, MBB->getNumber()),
OutContext);
break;
}
- // Otherwise, use the difference as the jump table entry.
Value = MCSymbolRefExpr::Create(MBB->getSymbol(), OutContext);
- const MCExpr *JTI = MCSymbolRefExpr::Create(GetJTISymbol(UID), OutContext);
- Value = MCBinaryExpr::CreateSub(Value, JTI, OutContext);
+ const TargetLowering *TLI = MF->getSubtarget().getTargetLowering();
+ const MCExpr *Base = TLI->getPICJumpTableRelocBaseExpr(MF, UID, OutContext);
+ Value = MCBinaryExpr::CreateSub(Value, Base, OutContext);
break;
}
}
assert(Value && "Unknown entry kind!");
- unsigned EntrySize = MJTI->getEntrySize(*TM.getDataLayout());
+ unsigned EntrySize =
+ MJTI->getEntrySize(*TM.getDataLayout());
OutStreamer.EmitValue(Value, EntrySize);
}
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
continue;
KeySym = getSymbol(GV);
- KeySec = getObjFileLowering().SectionForGlobal(GV, *Mang, TM);
}
const MCSection *OutputSection =
- (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym, KeySec)
- : Obj.getStaticDtorSection(S.Priority, KeySym, KeySec));
+ (isCtor ? Obj.getStaticCtorSection(S.Priority, KeySym)
+ : Obj.getStaticDtorSection(S.Priority, KeySym));
OutStreamer.SwitchSection(OutputSection);
if (OutStreamer.getCurrentSection() != OutStreamer.getPreviousSection())
EmitAlignment(Align);
OutStreamer.EmitIntValue(Value, 4);
}
-/// EmitLabelDifference - Emit something like ".long Hi-Lo" where the size
-/// in bytes of the directive is specified by Size and Hi/Lo specify the
-/// labels. This implicitly uses .set if it is available.
+/// Emit something like ".long Hi-Lo" where the size in bytes of the directive
+/// is specified by Size and Hi/Lo specify the labels. This implicitly uses
+/// .set if it avoids relocations.
void AsmPrinter::EmitLabelDifference(const MCSymbol *Hi, const MCSymbol *Lo,
unsigned Size) const {
// Get the Hi-Lo expression.
MCSymbolRefExpr::Create(Lo, OutContext),
OutContext);
- if (!MAI->hasSetDirective()) {
+ if (!MAI->doesSetDirectiveSuppressesReloc()) {
OutStreamer.EmitValue(Diff, Size);
return;
}
// Otherwise, emit with .set (aka assignment).
- MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
+ MCSymbol *SetLabel = createTempSymbol("set");
OutStreamer.EmitAssignment(SetLabel, Diff);
OutStreamer.EmitSymbolValue(SetLabel, Size);
}
-/// EmitLabelOffsetDifference - Emit something like ".long Hi+Offset-Lo"
-/// where the size in bytes of the directive is specified by Size and Hi/Lo
-/// specify the labels. This implicitly uses .set if it is available.
-void AsmPrinter::EmitLabelOffsetDifference(const MCSymbol *Hi, uint64_t Offset,
- const MCSymbol *Lo,
- unsigned Size) const {
-
- // Emit Hi+Offset - Lo
- // Get the Hi+Offset expression.
- const MCExpr *Plus =
- MCBinaryExpr::CreateAdd(MCSymbolRefExpr::Create(Hi, OutContext),
- MCConstantExpr::Create(Offset, OutContext),
- OutContext);
-
- // Get the Hi+Offset-Lo expression.
- const MCExpr *Diff =
- MCBinaryExpr::CreateSub(Plus,
- MCSymbolRefExpr::Create(Lo, OutContext),
- OutContext);
-
- if (!MAI->hasSetDirective())
- OutStreamer.EmitValue(Diff, Size);
- else {
- // Otherwise, emit with .set (aka assignment).
- MCSymbol *SetLabel = GetTempSymbol("set", SetCounter++);
- OutStreamer.EmitAssignment(SetLabel, Diff);
- OutStreamer.EmitSymbolValue(SetLabel, Size);
- }
-}
-
/// EmitLabelPlusOffset - Emit something like ".long Label+Offset"
/// where the size in bytes of the directive is specified by Size and Label
/// specifies the label. This implicitly uses .set if it is available.
// if required for correctness.
//
void AsmPrinter::EmitAlignment(unsigned NumBits, const GlobalObject *GV) const {
- if (GV) NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(), NumBits);
+ if (GV)
+ NumBits = getGVAlignmentLog2(GV, *TM.getDataLayout(),
+ NumBits);
if (NumBits == 0) return; // 1-byte aligned: no need to emit alignment.
+ assert(NumBits <
+ static_cast<unsigned>(std::numeric_limits<unsigned>::digits) &&
+ "undefined behavior");
if (getCurrentSection()->getKind().isText())
- OutStreamer.EmitCodeAlignment(1 << NumBits);
+ OutStreamer.EmitCodeAlignment(1u << NumBits);
else
- OutStreamer.EmitValueToAlignment(1 << NumBits);
+ OutStreamer.EmitValueToAlignment(1u << NumBits);
}
//===----------------------------------------------------------------------===//
// Constant emission.
//===----------------------------------------------------------------------===//
-/// lowerConstant - Lower the specified LLVM Constant to an MCExpr.
-///
-static const MCExpr *lowerConstant(const Constant *CV, AsmPrinter &AP) {
- MCContext &Ctx = AP.OutContext;
+const MCExpr *AsmPrinter::lowerConstant(const Constant *CV) {
+ MCContext &Ctx = OutContext;
if (CV->isNullValue() || isa<UndefValue>(CV))
return MCConstantExpr::Create(0, Ctx);
return MCConstantExpr::Create(CI->getZExtValue(), Ctx);
if (const GlobalValue *GV = dyn_cast<GlobalValue>(CV))
- return MCSymbolRefExpr::Create(AP.getSymbol(GV), Ctx);
+ return MCSymbolRefExpr::Create(getSymbol(GV), Ctx);
if (const BlockAddress *BA = dyn_cast<BlockAddress>(CV))
- return MCSymbolRefExpr::Create(AP.GetBlockAddressSymbol(BA), Ctx);
+ return MCSymbolRefExpr::Create(GetBlockAddressSymbol(BA), Ctx);
const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV);
if (!CE) {
llvm_unreachable("Unknown constant value to lower!");
}
- if (const MCExpr *RelocExpr =
- AP.getObjFileLowering().getExecutableRelativeSymbol(CE, *AP.Mang,
- AP.TM))
+ if (const MCExpr *RelocExpr
+ = getObjFileLowering().getExecutableRelativeSymbol(CE, *Mang, TM))
return RelocExpr;
switch (CE->getOpcode()) {
// If the code isn't optimized, there may be outstanding folding
// opportunities. Attempt to fold the expression using DataLayout as a
// last resort before giving up.
- if (Constant *C =
- ConstantFoldConstantExpression(CE, AP.TM.getDataLayout()))
+ if (Constant *C = ConstantFoldConstantExpression(CE, *TM.getDataLayout()))
if (C != CE)
- return lowerConstant(C, AP);
+ return lowerConstant(C);
// Otherwise report the problem to the user.
{
raw_string_ostream OS(S);
OS << "Unsupported expression in static initializer: ";
CE->printAsOperand(OS, /*PrintType=*/false,
- !AP.MF ? nullptr : AP.MF->getFunction()->getParent());
+ !MF ? nullptr : MF->getFunction()->getParent());
report_fatal_error(OS.str());
}
case Instruction::GetElementPtr: {
- const DataLayout &DL = *AP.TM.getDataLayout();
+ const DataLayout &DL = *TM.getDataLayout();
+
// Generate a symbolic expression for the byte address
APInt OffsetAI(DL.getPointerTypeSizeInBits(CE->getType()), 0);
cast<GEPOperator>(CE)->accumulateConstantOffset(DL, OffsetAI);
- const MCExpr *Base = lowerConstant(CE->getOperand(0), AP);
+ const MCExpr *Base = lowerConstant(CE->getOperand(0));
if (!OffsetAI)
return Base;
// is reasonable to treat their delta as a 32-bit value.
// FALL THROUGH.
case Instruction::BitCast:
- return lowerConstant(CE->getOperand(0), AP);
+ return lowerConstant(CE->getOperand(0));
case Instruction::IntToPtr: {
- const DataLayout &DL = *AP.TM.getDataLayout();
+ const DataLayout &DL = *TM.getDataLayout();
+
// Handle casts to pointers by changing them into casts to the appropriate
// integer type. This promotes constant folding and simplifies this code.
Constant *Op = CE->getOperand(0);
Op = ConstantExpr::getIntegerCast(Op, DL.getIntPtrType(CV->getType()),
false/*ZExt*/);
- return lowerConstant(Op, AP);
+ return lowerConstant(Op);
}
case Instruction::PtrToInt: {
- const DataLayout &DL = *AP.TM.getDataLayout();
+ const DataLayout &DL = *TM.getDataLayout();
+
// Support only foldable casts to/from pointers that can be eliminated by
// changing the pointer to the appropriately sized integer type.
Constant *Op = CE->getOperand(0);
Type *Ty = CE->getType();
- const MCExpr *OpExpr = lowerConstant(Op, AP);
+ const MCExpr *OpExpr = lowerConstant(Op);
// We can emit the pointer value into this slot if the slot is an
// integer slot equal to the size of the pointer.
case Instruction::And:
case Instruction::Or:
case Instruction::Xor: {
- const MCExpr *LHS = lowerConstant(CE->getOperand(0), AP);
- const MCExpr *RHS = lowerConstant(CE->getOperand(1), AP);
+ const MCExpr *LHS = lowerConstant(CE->getOperand(0));
+ const MCExpr *RHS = lowerConstant(CE->getOperand(1));
switch (CE->getOpcode()) {
default: llvm_unreachable("Unknown binary operator constant cast expr");
case Instruction::Add: return MCBinaryExpr::CreateAdd(LHS, RHS, Ctx);
}
}
-static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP);
+static void emitGlobalConstantImpl(const Constant *C, AsmPrinter &AP,
+ const Constant *BaseCV = nullptr,
+ uint64_t Offset = 0);
/// isRepeatedByteSequence - Determine whether the given value is
/// composed of a repeated sequence of identical bytes and return the
if (const ConstantInt *CI = dyn_cast<ConstantInt>(V)) {
if (CI->getBitWidth() > 64) return -1;
- uint64_t Size = TM.getDataLayout()->getTypeAllocSize(V->getType());
+ uint64_t Size =
+ TM.getDataLayout()->getTypeAllocSize(V->getType());
uint64_t Value = CI->getZExtValue();
// Make sure the constant is at least 8 bits long and has a power
// See if we can aggregate this into a .fill, if so, emit it as such.
int Value = isRepeatedByteSequence(CDS, AP.TM);
if (Value != -1) {
- uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CDS->getType());
+ uint64_t Bytes =
+ AP.TM.getDataLayout()->getTypeAllocSize(
+ CDS->getType());
// Don't emit a 1-byte object as a .fill.
if (Bytes > 1)
return AP.OutStreamer.EmitFill(Bytes, Value);
}
-static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP) {
+static void emitGlobalConstantArray(const ConstantArray *CA, AsmPrinter &AP,
+ const Constant *BaseCV, uint64_t Offset) {
// See if we can aggregate some values. Make sure it can be
// represented as a series of bytes of the constant value.
int Value = isRepeatedByteSequence(CA, AP.TM);
+ const DataLayout &DL = *AP.TM.getDataLayout();
if (Value != -1) {
- uint64_t Bytes = AP.TM.getDataLayout()->getTypeAllocSize(CA->getType());
+ uint64_t Bytes = DL.getTypeAllocSize(CA->getType());
AP.OutStreamer.EmitFill(Bytes, Value);
}
else {
- for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i)
- emitGlobalConstantImpl(CA->getOperand(i), AP);
+ for (unsigned i = 0, e = CA->getNumOperands(); i != e; ++i) {
+ emitGlobalConstantImpl(CA->getOperand(i), AP, BaseCV, Offset);
+ Offset += DL.getTypeAllocSize(CA->getOperand(i)->getType());
+ }
}
}
AP.OutStreamer.EmitZeros(Padding);
}
-static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP) {
+static void emitGlobalConstantStruct(const ConstantStruct *CS, AsmPrinter &AP,
+ const Constant *BaseCV, uint64_t Offset) {
// Print the fields in successive locations. Pad to align if needed!
const DataLayout *DL = AP.TM.getDataLayout();
unsigned Size = DL->getTypeAllocSize(CS->getType());
for (unsigned i = 0, e = CS->getNumOperands(); i != e; ++i) {
const Constant *Field = CS->getOperand(i);
+ // Print the actual field value.
+ emitGlobalConstantImpl(Field, AP, BaseCV, Offset+SizeSoFar);
+
// Check if padding is needed and insert one or more 0s.
uint64_t FieldSize = DL->getTypeAllocSize(Field->getType());
uint64_t PadSize = ((i == e-1 ? Size : Layout->getElementOffset(i+1))
- Layout->getElementOffset(i)) - FieldSize;
SizeSoFar += FieldSize + PadSize;
- // Now print the actual field value.
- emitGlobalConstantImpl(Field, AP);
-
// Insert padding - this may include padding to increase the size of the
// current field up to the ABI size (if the struct is not packed) as well
// as padding to ensure that the next field starts at the right offset.
SmallString<8> StrVal;
CFP->getValueAPF().toString(StrVal);
- CFP->getType()->print(AP.OutStreamer.GetCommentOS());
+ if (CFP->getType())
+ CFP->getType()->print(AP.OutStreamer.GetCommentOS());
+ else
+ AP.OutStreamer.GetCommentOS() << "Printing <null> Type";
AP.OutStreamer.GetCommentOS() << ' ' << StrVal << '\n';
}
// PPC's long double has odd notions of endianness compared to how LLVM
// handles it: p[0] goes first for *big* endian on PPC.
- if (AP.TM.getDataLayout()->isBigEndian() != CFP->getType()->isPPC_FP128Ty()) {
+ if (AP.TM.getDataLayout()->isBigEndian() &&
+ !CFP->getType()->isPPC_FP128Ty()) {
int Chunk = API.getNumWords() - 1;
if (TrailingBytes)
// Emit the extra bits after the 64-bits chunks.
// Emit a directive that fills the expected size.
- uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(CI->getType());
+ uint64_t Size = AP.TM.getDataLayout()->getTypeAllocSize(
+ CI->getType());
Size -= (BitWidth / 64) * 8;
assert(Size && Size * 8 >= ExtraBitsSize &&
(ExtraBits & (((uint64_t)-1) >> (64 - ExtraBitsSize)))
}
}
-static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP) {
+/// \brief Transform a not absolute MCExpr containing a reference to a GOT
+/// equivalent global, by a target specific GOT pc relative access to the
+/// final symbol.
+static void handleIndirectSymViaGOTPCRel(AsmPrinter &AP, const MCExpr **ME,
+ const Constant *BaseCst,
+ uint64_t Offset) {
+ // The global @foo below illustrates a global that uses a got equivalent.
+ //
+ // @bar = global i32 42
+ // @gotequiv = private unnamed_addr constant i32* @bar
+ // @foo = i32 trunc (i64 sub (i64 ptrtoint (i32** @gotequiv to i64),
+ // i64 ptrtoint (i32* @foo to i64))
+ // to i32)
+ //
+ // The cstexpr in @foo is converted into the MCExpr `ME`, where we actually
+ // check whether @foo is suitable to use a GOTPCREL. `ME` is usually in the
+ // form:
+ //
+ // foo = cstexpr, where
+ // cstexpr := <gotequiv> - "." + <cst>
+ // cstexpr := <gotequiv> - (<foo> - <offset from @foo base>) + <cst>
+ //
+ // After canonicalization by EvaluateAsRelocatable `ME` turns into:
+ //
+ // cstexpr := <gotequiv> - <foo> + gotpcrelcst, where
+ // gotpcrelcst := <offset from @foo base> + <cst>
+ //
+ MCValue MV;
+ if (!(*ME)->EvaluateAsRelocatable(MV, nullptr, nullptr) || MV.isAbsolute())
+ return;
+
+ const MCSymbol *GOTEquivSym = &MV.getSymA()->getSymbol();
+ if (!AP.GlobalGOTEquivs.count(GOTEquivSym))
+ return;
+
+ const GlobalValue *BaseGV = dyn_cast<GlobalValue>(BaseCst);
+ if (!BaseGV)
+ return;
+
+ const MCSymbol *BaseSym = AP.getSymbol(BaseGV);
+ if (BaseSym != &MV.getSymB()->getSymbol())
+ return;
+
+ // Make sure to match:
+ //
+ // gotpcrelcst := <offset from @foo base> + <cst>
+ //
+ // If gotpcrelcst is positive it means that we can safely fold the pc rel
+ // displacement into the GOTPCREL. We can also can have an extra offset <cst>
+ // if the target knows how to encode it.
+ //
+ int64_t GOTPCRelCst = Offset + MV.getConstant();
+ if (GOTPCRelCst < 0)
+ return;
+ if (!AP.getObjFileLowering().supportGOTPCRelWithOffset() && GOTPCRelCst != 0)
+ return;
+
+ // Emit the GOT PC relative to replace the got equivalent global, i.e.:
+ //
+ // bar:
+ // .long 42
+ // gotequiv:
+ // .quad bar
+ // foo:
+ // .long gotequiv - "." + <cst>
+ //
+ // is replaced by the target specific equivalent to:
+ //
+ // bar:
+ // .long 42
+ // foo:
+ // .long bar@GOTPCREL+<gotpcrelcst>
+ //
+ AsmPrinter::GOTEquivUsePair Result = AP.GlobalGOTEquivs[GOTEquivSym];
+ const GlobalVariable *GV = Result.first;
+ int NumUses = (int)Result.second;
+ const GlobalValue *FinalGV = dyn_cast<GlobalValue>(GV->getOperand(0));
+ const MCSymbol *FinalSym = AP.getSymbol(FinalGV);
+ *ME = AP.getObjFileLowering().getIndirectSymViaGOTPCRel(
+ FinalSym, MV, Offset, AP.MMI, AP.OutStreamer);
+
+ // Update GOT equivalent usage information
+ --NumUses;
+ if (NumUses >= 0)
+ AP.GlobalGOTEquivs[GOTEquivSym] = std::make_pair(GV, NumUses);
+}
+
+static void emitGlobalConstantImpl(const Constant *CV, AsmPrinter &AP,
+ const Constant *BaseCV, uint64_t Offset) {
const DataLayout *DL = AP.TM.getDataLayout();
uint64_t Size = DL->getTypeAllocSize(CV->getType());
+
+ // Globals with sub-elements such as combinations of arrays and structs
+ // are handled recursively by emitGlobalConstantImpl. Keep track of the
+ // constant symbol base and the current position with BaseCV and Offset.
+ if (!BaseCV && CV->hasOneUse())
+ BaseCV = dyn_cast<Constant>(CV->user_back());
+
if (isa<ConstantAggregateZero>(CV) || isa<UndefValue>(CV))
return AP.OutStreamer.EmitZeros(Size);
return emitGlobalConstantDataSequential(CDS, AP);
if (const ConstantArray *CVA = dyn_cast<ConstantArray>(CV))
- return emitGlobalConstantArray(CVA, AP);
+ return emitGlobalConstantArray(CVA, AP, BaseCV, Offset);
if (const ConstantStruct *CVS = dyn_cast<ConstantStruct>(CV))
- return emitGlobalConstantStruct(CVS, AP);
+ return emitGlobalConstantStruct(CVS, AP, BaseCV, Offset);
if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(CV)) {
// Look through bitcasts, which might not be able to be MCExpr'ized (e.g. of
// If the constant expression's size is greater than 64-bits, then we have
// to emit the value in chunks. Try to constant fold the value and emit it
// that way.
- Constant *New = ConstantFoldConstantExpression(CE, DL);
+ Constant *New = ConstantFoldConstantExpression(CE, *DL);
if (New && New != CE)
return emitGlobalConstantImpl(New, AP);
}
// Otherwise, it must be a ConstantExpr. Lower it to an MCExpr, then emit it
// thread the streamer with EmitValue.
- AP.OutStreamer.EmitValue(lowerConstant(CV, AP), Size);
+ const MCExpr *ME = AP.lowerConstant(CV);
+
+ // Since lowerConstant already folded and got rid of all IR pointer and
+ // integer casts, detect GOT equivalent accesses by looking into the MCExpr
+ // directly.
+ if (AP.getObjFileLowering().supportIndirectSymViaGOTPCRel())
+ handleIndirectSymViaGOTPCRel(AP, &ME, BaseCV, Offset);
+
+ AP.OutStreamer.EmitValue(ME, Size);
}
/// EmitGlobalConstant - Print a general LLVM constant to the .s file.
void AsmPrinter::EmitGlobalConstant(const Constant *CV) {
- uint64_t Size = TM.getDataLayout()->getTypeAllocSize(CV->getType());
+ uint64_t Size =
+ TM.getDataLayout()->getTypeAllocSize(CV->getType());
if (Size)
emitGlobalConstantImpl(CV, *this);
else if (MAI->hasSubsectionsViaSymbols()) {
// Symbol Lowering Routines.
//===----------------------------------------------------------------------===//
-/// GetTempSymbol - Return the MCSymbol corresponding to the assembler
-/// temporary label with the specified stem and unique ID.
-MCSymbol *AsmPrinter::GetTempSymbol(Twine Name, unsigned ID) const {
- const DataLayout *DL = TM.getDataLayout();
- return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix()) +
- Name + Twine(ID));
-}
-
-/// GetTempSymbol - Return an assembler temporary label with the specified
-/// stem.
-MCSymbol *AsmPrinter::GetTempSymbol(Twine Name) const {
- const DataLayout *DL = TM.getDataLayout();
- return OutContext.GetOrCreateSymbol(Twine(DL->getPrivateGlobalPrefix())+
- Name);
+MCSymbol *AsmPrinter::createTempSymbol(const Twine &Name) const {
+ return OutContext.createTempSymbol(Name, true);
}
-
MCSymbol *AsmPrinter::GetBlockAddressSymbol(const BlockAddress *BA) const {
return MMI->getAddrLabelSymbol(BA->getBasicBlock());
}
MCSymbol *AsmPrinter::GetExternalSymbolSymbol(StringRef Sym) const {
SmallString<60> NameStr;
Mang->getNameWithPrefix(NameStr, Sym);
- return OutContext.GetOrCreateSymbol(NameStr.str());
+ return OutContext.GetOrCreateSymbol(NameStr);
}
if (!S.usesMetadata())
return nullptr;
+ assert(!S.useStatepoints() && "statepoints do not currently support custom"
+ " stackmap formats, please see the documentation for a description of"
+ " the default format. If you really need a custom serialized format,"
+ " please file a bug");
+
gcp_map_type &GCMap = getGCMap(GCMetadataPrinters);
gcp_map_type::iterator GCPI = GCMap.find(&S);
if (GCPI != GCMap.end())
/// Pin vtable to this file.
AsmPrinterHandler::~AsmPrinterHandler() {}
+
+void AsmPrinterHandler::markFunctionEnd() {}
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