index 99e7a272d7fdfa952a623f30cdd997c75d54b258..a669077f08b48fad4cc63b9e43d140c023f417b4 100644 (file)
#include "llvm/Target/TargetMachine.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/Target/TargetRegisterInfo.h"
+#include "llvm/Target/TargetSubtargetInfo.h"
using namespace llvm;
#define DEBUG_TYPE "dwarfdebug"
if (tag == dwarf::DW_TAG_pointer_type)
subType = resolve(DIDerivedType(Ty).getTypeDerivedFrom());
- DIArray Elements = DICompositeType(subType).getTypeArray();
+ DIArray Elements = DICompositeType(subType).getElements();
for (unsigned i = 0, N = Elements.getNumElements(); i < N; ++i) {
DIDerivedType DT(Elements.getElement(i));
if (getName() == DT.getName())
attachLowHighPC(SPCU, *SPDie, FunctionBeginSym, FunctionEndSym);
- const TargetRegisterInfo *RI = Asm->TM.getRegisterInfo();
+ const TargetRegisterInfo *RI = Asm->TM.getSubtargetImpl()->getRegisterInfo();
MachineLocation Location(RI->getFrameRegister(*Asm->MF));
SPCU.addAddress(*SPDie, dwarf::DW_AT_frame_base, Location);
// If this is a variadic function, add an unspecified parameter.
DISubprogram SP(Scope->getScopeNode());
- DIArray FnArgs = SP.getType().getTypeArray();
- if (FnArgs.getElement(FnArgs.getNumElements() - 1)
- .isUnspecifiedParameter()) {
+ DITypeArray FnArgs = SP.getType().getTypeArray();
+ // If we have a single element of null, it is a function that returns void.
+ // If we have more than one elements and the last one is null, it is a
+ // variadic function.
+ if (FnArgs.getNumElements() > 1 &&
+ !FnArgs.getElement(FnArgs.getNumElements() - 1))
Children.push_back(
make_unique<DIE>(dwarf::DW_TAG_unspecified_parameters));
- }
}
// Collect lexical scope children first.
for (unsigned i = 0, e = SPs.getNumElements(); i != e; ++i)
SPMap.insert(std::make_pair(SPs.getElement(i), &CU));
DIArray EnumTypes = CUNode.getEnumTypes();
- for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i)
- CU.getOrCreateTypeDIE(EnumTypes.getElement(i));
+ for (unsigned i = 0, e = EnumTypes.getNumElements(); i != e; ++i) {
+ DIType Ty(EnumTypes.getElement(i));
+ // The enum types array by design contains pointers to
+ // MDNodes rather than DIRefs. Unique them here.
+ DIType UniqueTy(resolve(Ty.getRef()));
+ CU.getOrCreateTypeDIE(UniqueTy);
+ }
DIArray RetainedTypes = CUNode.getRetainedTypes();
for (unsigned i = 0, e = RetainedTypes.getNumElements(); i != e; ++i) {
DIType Ty(RetainedTypes.getElement(i));
@@ -1136,6 +1144,7 @@ bool DwarfDebug::addCurrentFnArgument(DbgVariable *Var, LexicalScope *Scope) {
// arguments does the function have at source level.
if (ArgNo > Size)
CurrentFnArguments.resize(ArgNo * 2);
+ assert(!CurrentFnArguments[ArgNo - 1]);
CurrentFnArguments[ArgNo - 1] = Var;
return true;
}
llvm_unreachable("Unexpected 3 operand DBG_VALUE instruction!");
}
+/// Determine whether two variable pieces overlap.
+static bool piecesOverlap(DIVariable P1, DIVariable P2) {
+ if (!P1.isVariablePiece() || !P2.isVariablePiece())
+ return true;
+ unsigned l1 = P1.getPieceOffset();
+ unsigned l2 = P2.getPieceOffset();
+ unsigned r1 = l1 + P1.getPieceSize();
+ unsigned r2 = l2 + P2.getPieceSize();
+ // True where [l1,r1[ and [r1,r2[ overlap.
+ return (l1 < r2) && (l2 < r1);
+}
+
+/// Build the location list for all DBG_VALUEs in the function that
+/// describe the same variable. If the ranges of several independent
+/// pieces of the same variable overlap partially, split them up and
+/// combine the ranges. The resulting DebugLocEntries are will have
+/// strict monotonically increasing begin addresses and will never
+/// overlap.
+//
+// Input:
+//
+// Ranges History [var, loc, piece ofs size]
+// 0 | [x, (reg0, piece 0, 32)]
+// 1 | | [x, (reg1, piece 32, 32)] <- IsPieceOfPrevEntry
+// 2 | | ...
+// 3 | [clobber reg0]
+// 4 [x, (mem, piece 0, 64)] <- overlapping with both previous pieces of x.
+//
+// Output:
+//
+// [0-1] [x, (reg0, piece 0, 32)]
+// [1-3] [x, (reg0, piece 0, 32), (reg1, piece 32, 32)]
+// [3-4] [x, (reg1, piece 32, 32)]
+// [4- ] [x, (mem, piece 0, 64)]
+void
+DwarfDebug::buildLocationList(SmallVectorImpl<DebugLocEntry> &DebugLoc,
+ const DbgValueHistoryMap::InstrRanges &Ranges) {
+ SmallVector<DebugLocEntry::Value, 4> OpenRanges;
+
+ for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
+ const MachineInstr *Begin = I->first;
+ const MachineInstr *End = I->second;
+ assert(Begin->isDebugValue() && "Invalid History entry");
+
+ // Check if a variable is inaccessible in this range.
+ if (!Begin->isDebugValue() ||
+ (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
+ !Begin->getOperand(0).getReg())) {
+ OpenRanges.clear();
+ continue;
+ }
+
+ // If this piece overlaps with any open ranges, truncate them.
+ DIVariable DIVar = Begin->getDebugVariable();
+ auto Last = std::remove_if(OpenRanges.begin(), OpenRanges.end(),
+ [&](DebugLocEntry::Value R) {
+ return piecesOverlap(DIVar, DIVariable(R.getVariable()));
+ });
+ OpenRanges.erase(Last, OpenRanges.end());
+
+ const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
+ assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
+
+ const MCSymbol *EndLabel;
+ if (End != nullptr)
+ EndLabel = getLabelAfterInsn(End);
+ else if (std::next(I) == Ranges.end())
+ EndLabel = FunctionEndSym;
+ else
+ EndLabel = getLabelBeforeInsn(std::next(I)->first);
+ assert(EndLabel && "Forgot label after instruction ending a range!");
+
+ DEBUG(dbgs() << "DotDebugLoc: " << *Begin << "\n");
+
+ auto Value = getDebugLocValue(Begin);
+ DebugLocEntry Loc(StartLabel, EndLabel, Value);
+ bool couldMerge = false;
+
+ // If this is a piece, it may belong to the current DebugLocEntry.
+ if (DIVar.isVariablePiece()) {
+ // Add this value to the list of open ranges.
+ OpenRanges.push_back(Value);
+
+ // Attempt to add the piece to the last entry.
+ if (!DebugLoc.empty())
+ if (DebugLoc.back().MergeValues(Loc))
+ couldMerge = true;
+ }
+
+ if (!couldMerge) {
+ // Need to add a new DebugLocEntry. Add all values from still
+ // valid non-overlapping pieces.
+ if (OpenRanges.size())
+ Loc.addValues(OpenRanges);
+
+ DebugLoc.push_back(std::move(Loc));
+ }
+
+ // Attempt to coalesce the ranges of two otherwise identical
+ // DebugLocEntries.
+ auto CurEntry = DebugLoc.rbegin();
+ auto PrevEntry = std::next(CurEntry);
+ if (PrevEntry != DebugLoc.rend() && PrevEntry->MergeRanges(*CurEntry))
+ DebugLoc.pop_back();
+
+ DEBUG(dbgs() << "Values:\n";
+ for (auto Value : CurEntry->getValues())
+ Value.getVariable()->dump();
+ dbgs() << "-----\n");
+ }
+}
+
+
// Find variables for each lexical scope.
void
DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
@@ -1207,10 +1329,7 @@ DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
continue;
LexicalScope *Scope = nullptr;
- if (DV.getTag() == dwarf::DW_TAG_arg_variable &&
- DISubprogram(DV.getContext()).describes(CurFn->getFunction()))
- Scope = LScopes.getCurrentFunctionScope();
- else if (MDNode *IA = DV.getInlinedAt()) {
+ if (MDNode *IA = DV.getInlinedAt()) {
DebugLoc DL = DebugLoc::getFromDILocation(IA);
Scope = LScopes.findInlinedScope(DebugLoc::get(
DL.getLine(), DL.getCol(), DV.getContext(), IA));
if (!Scope)
continue;
- Processed.insert(DV);
+ Processed.insert(getEntireVariable(DV));
const MachineInstr *MInsn = Ranges.front().first;
assert(MInsn->isDebugValue() && "History must begin with debug value");
ensureAbstractVariableIsCreatedIfScoped(DV, Scope->getScopeNode());
@@ -1237,40 +1356,12 @@ DwarfDebug::collectVariableInfo(SmallPtrSet<const MDNode *, 16> &Processed) {
DotDebugLocEntries.resize(DotDebugLocEntries.size() + 1);
DebugLocList &LocList = DotDebugLocEntries.back();
+ LocList.CU = TheCU;
LocList.Label =
Asm->GetTempSymbol("debug_loc", DotDebugLocEntries.size() - 1);
- SmallVector<DebugLocEntry, 4> &DebugLoc = LocList.List;
- for (auto I = Ranges.begin(), E = Ranges.end(); I != E; ++I) {
- const MachineInstr *Begin = I->first;
- const MachineInstr *End = I->second;
- assert(Begin->isDebugValue() && "Invalid History entry");
-
- // Check if a variable is unaccessible in this range.
- if (Begin->getNumOperands() > 1 && Begin->getOperand(0).isReg() &&
- !Begin->getOperand(0).getReg())
- continue;
- DEBUG(dbgs() << "DotDebugLoc Pair:\n" << "\t" << *Begin);
- if (End != nullptr)
- DEBUG(dbgs() << "\t" << *End);
- else
- DEBUG(dbgs() << "\tNULL\n");
-
- const MCSymbol *StartLabel = getLabelBeforeInsn(Begin);
- assert(StartLabel && "Forgot label before DBG_VALUE starting a range!");
-
- const MCSymbol *EndLabel;
- if (End != nullptr)
- EndLabel = getLabelAfterInsn(End);
- else if (std::next(I) == Ranges.end())
- EndLabel = FunctionEndSym;
- else
- EndLabel = getLabelBeforeInsn(std::next(I)->first);
- assert(EndLabel && "Forgot label after instruction ending a range!");
-
- DebugLocEntry Loc(StartLabel, EndLabel, getDebugLocValue(Begin), TheCU);
- if (DebugLoc.empty() || !DebugLoc.back().Merge(Loc))
- DebugLoc.push_back(std::move(Loc));
- }
+
+ // Build the location list for this variable.
+ buildLocationList(LocList.List, Ranges);
}
// Collect info for variables that were optimized out.
Asm->OutStreamer.EmitLabel(FunctionBeginSym);
// Calculate history for local variables.
- calculateDbgValueHistory(MF, Asm->TM.getRegisterInfo(), DbgValues);
+ calculateDbgValueHistory(MF, Asm->TM.getSubtargetImpl()->getRegisterInfo(),
+ DbgValues);
// Request labels for the full history.
for (const auto &I : DbgValues) {
// The first mention of a function argument gets the FunctionBeginSym
// label, so arguments are visible when breaking at function entry.
- DIVariable DV(I.first);
+ DIVariable DV(Ranges.front().first->getDebugVariable());
if (DV.isVariable() && DV.getTag() == dwarf::DW_TAG_arg_variable &&
- getDISubprogram(DV.getContext()).describes(MF->getFunction()))
- LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
+ getDISubprogram(DV.getContext()).describes(MF->getFunction())) {
+ if (!DV.isVariablePiece())
+ LabelsBeforeInsn[Ranges.front().first] = FunctionBeginSym;
+ else {
+ // Mark all non-overlapping initial pieces.
+ for (auto I = Ranges.begin(); I != Ranges.end(); ++I) {
+ DIVariable Piece = I->first->getDebugVariable();
+ if (std::all_of(Ranges.begin(), I,
+ [&](DbgValueHistoryMap::InstrRange Pred){
+ return !piecesOverlap(Piece, Pred.first->getDebugVariable());
+ }))
+ LabelsBeforeInsn[I->first] = FunctionBeginSym;
+ else
+ break;
+ }
+ }
+ }
for (const auto &Range : Ranges) {
requestLabelBeforeInsn(Range.first);
// Dwarf sections base addresses.
DwarfInfoSectionSym =
emitSectionSym(Asm, TLOF.getDwarfInfoSection(), "section_info");
- if (useSplitDwarf())
+ if (useSplitDwarf()) {
DwarfInfoDWOSectionSym =
emitSectionSym(Asm, TLOF.getDwarfInfoDWOSection(), "section_info_dwo");
+ DwarfTypesDWOSectionSym =
+ emitSectionSym(Asm, TLOF.getDwarfTypesDWOSection(), "section_types_dwo");
+ }
DwarfAbbrevSectionSym =
emitSectionSym(Asm, TLOF.getDwarfAbbrevSection(), "section_abbrev");
if (useSplitDwarf())
Holder.emitStrings(Asm->getObjFileLowering().getDwarfStrSection());
}
+/// Emits an optimal (=sorted) sequence of DW_OP_pieces.
+void DwarfDebug::emitLocPieces(ByteStreamer &Streamer,
+ const DITypeIdentifierMap &Map,
+ ArrayRef<DebugLocEntry::Value> Values) {
+ assert(std::all_of(Values.begin(), Values.end(), [](DebugLocEntry::Value P) {
+ return DIVariable(P.getVariable()).isVariablePiece();
+ }) && "all values are expected to be pieces");
+ assert(std::is_sorted(Values.begin(), Values.end()) &&
+ "pieces are expected to be sorted");
+
+ unsigned Offset = 0;
+ for (auto Piece : Values) {
+ DIVariable Var(Piece.getVariable());
+ unsigned PieceOffset = Var.getPieceOffset();
+ unsigned PieceSize = Var.getPieceSize();
+ assert(Offset <= PieceOffset && "overlapping or duplicate pieces");
+ if (Offset < PieceOffset) {
+ // The DWARF spec seriously mandates pieces with no locations for gaps.
+ Asm->EmitDwarfOpPiece(Streamer, (PieceOffset-Offset)*8);
+ Offset += PieceOffset-Offset;
+ }
+
+ Offset += PieceSize;
+
+ const unsigned SizeOfByte = 8;
+ assert(!Var.isIndirect() && "indirect address for piece");
+#ifndef NDEBUG
+ unsigned VarSize = Var.getSizeInBits(Map);
+ assert(PieceSize+PieceOffset <= VarSize/SizeOfByte
+ && "piece is larger than or outside of variable");
+ assert(PieceSize*SizeOfByte != VarSize
+ && "piece covers entire variable");
+#endif
+ if (Piece.isLocation() && Piece.getLoc().isReg())
+ Asm->EmitDwarfRegOpPiece(Streamer,
+ Piece.getLoc(),
+ PieceSize*SizeOfByte);
+ else {
+ emitDebugLocValue(Streamer, Piece);
+ Asm->EmitDwarfOpPiece(Streamer, PieceSize*SizeOfByte);
+ }
+ }
+}
+
+
void DwarfDebug::emitDebugLocEntry(ByteStreamer &Streamer,
const DebugLocEntry &Entry) {
- assert(Entry.getValues().size() == 1 &&
- "multi-value entries are not supported yet.");
const DebugLocEntry::Value Value = Entry.getValues()[0];
DIVariable DV(Value.getVariable());
+ if (DV.isVariablePiece())
+ // Emit all pieces that belong to the same variable and range.
+ return emitLocPieces(Streamer, TypeIdentifierMap, Entry.getValues());
+
+ assert(Entry.getValues().size() == 1 && "only pieces may have >1 value");
+ emitDebugLocValue(Streamer, Value);
+}
+
+void DwarfDebug::emitDebugLocValue(ByteStreamer &Streamer,
+ const DebugLocEntry::Value &Value) {
+ DIVariable DV(Value.getVariable());
+ // Regular entry.
if (Value.isInt()) {
DIBasicType BTy(resolve(DV.getType()));
if (BTy.Verify() && (BTy.getEncoding() == dwarf::DW_ATE_signed ||
} else if (Element == DIBuilder::OpDeref) {
if (!Loc.isReg())
Streamer.EmitInt8(dwarf::DW_OP_deref, "DW_OP_deref");
+ } else if (Element == DIBuilder::OpPiece) {
+ i += 3;
+ // handled in emitDebugLocEntry.
} else
llvm_unreachable("unknown Opcode found in complex address");
}
unsigned char Size = Asm->getDataLayout().getPointerSize();
for (const auto &DebugLoc : DotDebugLocEntries) {
Asm->OutStreamer.EmitLabel(DebugLoc.Label);
+ const DwarfCompileUnit *CU = DebugLoc.CU;
+ assert(!CU->getRanges().empty());
for (const auto &Entry : DebugLoc.List) {
// Set up the range. This range is relative to the entry point of the
// compile unit. This is a hard coded 0 for low_pc when we're emitting
// ranges, or the DW_AT_low_pc on the compile unit otherwise.
- const DwarfCompileUnit *CU = Entry.getCU();
if (CU->getRanges().size() == 1) {
// Grab the begin symbol from the first range as our base.
const MCSymbol *Base = CU->getRanges()[0].getStart();
bool TopLevelType = TypeUnitsUnderConstruction.empty();
AddrPool.resetUsedFlag();
- auto OwnedUnit =
- make_unique<DwarfTypeUnit>(InfoHolder.getUnits().size(), CU, Asm, this,
- &InfoHolder, getDwoLineTable(CU));
+ auto OwnedUnit = make_unique<DwarfTypeUnit>(
+ InfoHolder.getUnits().size() + TypeUnitsUnderConstruction.size(), CU, Asm,
+ this, &InfoHolder, getDwoLineTable(CU));
DwarfTypeUnit &NewTU = *OwnedUnit;
DIE &UnitDie = NewTU.getUnitDie();
TU = &NewTU;
uint64_t Signature = makeTypeSignature(Identifier);
NewTU.setTypeSignature(Signature);
- if (!useSplitDwarf())
+ if (useSplitDwarf())
+ NewTU.initSection(Asm->getObjFileLowering().getDwarfTypesDWOSection(),
+ DwarfTypesDWOSectionSym);
+ else {
CU.applyStmtList(UnitDie);
-
- // FIXME: Skip using COMDAT groups for type units in the .dwo file once tools
- // such as DWP ( http://gcc.gnu.org/wiki/DebugFissionDWP ) can cope with it.
- NewTU.initSection(
- useSplitDwarf()
- ? Asm->getObjFileLowering().getDwarfTypesDWOSection(Signature)
- : Asm->getObjFileLowering().getDwarfTypesSection(Signature));
+ NewTU.initSection(
+ Asm->getObjFileLowering().getDwarfTypesSection(Signature));
+ }
NewTU.setType(NewTU.createTypeDIE(CTy));