Revert "Refactor the RelocVisitor::visit method"
[oota-llvm.git] / lib / DebugInfo / DWARFDebugInfoEntry.cpp
index 9bb49df5d1309c5cdf661a4aa8b9569b7343c436..81a976e4da1298acf4dd4a6c1b2582ab1f272abb 100644 (file)
 #include "llvm/Support/raw_ostream.h"
 using namespace llvm;
 using namespace dwarf;
+typedef DILineInfoSpecifier::FunctionNameKind FunctionNameKind;
+
+// Small helper to extract a DIE pointed by a reference
+// attribute. It looks up the Unit containing the DIE and calls
+// DIE.extractFast with the right unit. Returns new unit on success,
+// nullptr otherwise.
+static const DWARFUnit *findUnitAndExtractFast(DWARFDebugInfoEntryMinimal &DIE,
+                                               const DWARFUnit *Unit,
+                                               uint32_t *Offset) {
+  Unit = Unit->getUnitSection().getUnitForOffset(*Offset);
+  return (Unit && DIE.extractFast(Unit, Offset)) ? Unit : nullptr;
+}
 
-void DWARFDebugInfoEntryMinimal::dump(raw_ostream &OS, const DWARFUnit *u,
+void DWARFDebugInfoEntryMinimal::dump(raw_ostream &OS, DWARFUnit *u,
                                       unsigned recurseDepth,
                                       unsigned indent) const {
   DataExtractor debug_info_data = u->getDebugInfoExtractor();
@@ -40,11 +52,8 @@ void DWARFDebugInfoEntryMinimal::dump(raw_ostream &OS, const DWARFUnit *u,
                      AbbrevDecl->hasChildren() ? '*' : ' ');
 
         // Dump all data in the DIE for the attributes.
-        const uint32_t numAttributes = AbbrevDecl->getNumAttributes();
-        for (uint32_t i = 0; i != numAttributes; ++i) {
-          uint16_t attr = AbbrevDecl->getAttrByIndex(i);
-          uint16_t form = AbbrevDecl->getFormByIndex(i);
-          dumpAttribute(OS, u, &offset, attr, form, indent);
+        for (const auto &AttrSpec : AbbrevDecl->attributes()) {
+          dumpAttribute(OS, u, &offset, AttrSpec.Attr, AttrSpec.Form, indent);
         }
 
         const DWARFDebugInfoEntryMinimal *child = getFirstChild();
@@ -65,7 +74,7 @@ void DWARFDebugInfoEntryMinimal::dump(raw_ostream &OS, const DWARFUnit *u,
 }
 
 void DWARFDebugInfoEntryMinimal::dumpAttribute(raw_ostream &OS,
-                                               const DWARFUnit *u,
+                                               DWARFUnit *u,
                                                uint32_t *offset_ptr,
                                                uint16_t attr, uint16_t form,
                                                unsigned indent) const {
@@ -88,82 +97,64 @@ void DWARFDebugInfoEntryMinimal::dumpAttribute(raw_ostream &OS,
     return;
 
   OS << "\t(";
-  formValue.dump(OS, u);
+  
+  const char *Name = nullptr;
+  std::string File;
+  if (attr == DW_AT_decl_file || attr == DW_AT_call_file) {
+    if (const auto *LT = u->getContext().getLineTableForUnit(u))
+      if (LT->getFileNameByIndex(
+             formValue.getAsUnsignedConstant().getValue(),
+             u->getCompilationDir(),
+             DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, File)) {
+        File = '"' + File + '"';
+        Name = File.c_str();
+      }
+  } else if (Optional<uint64_t> Val = formValue.getAsUnsignedConstant())
+    Name = AttributeValueString(attr, *Val);
+
+  if (Name) {
+    OS << Name;
+  } else if (attr == DW_AT_decl_line || attr == DW_AT_call_line) {
+    OS << *formValue.getAsUnsignedConstant();
+  } else {
+    formValue.dump(OS, u);
+  }
+
   OS << ")\n";
 }
 
 bool DWARFDebugInfoEntryMinimal::extractFast(const DWARFUnit *U,
-                                             const uint8_t *FixedFormSizes,
                                              uint32_t *OffsetPtr) {
   Offset = *OffsetPtr;
   DataExtractor DebugInfoData = U->getDebugInfoExtractor();
-  uint64_t AbbrCode = DebugInfoData.getULEB128(OffsetPtr);
-  if (0 == AbbrCode) {
-    // NULL debug tag entry.
-    AbbrevDecl = NULL;
-    return true;
-  }
-  AbbrevDecl = U->getAbbreviations()->getAbbreviationDeclaration(AbbrCode);
-  assert(AbbrevDecl);
-  assert(FixedFormSizes); // For best performance this should be specified!
-
-  // Skip all data in the .debug_info for the attributes
-  for (uint32_t i = 0, n = AbbrevDecl->getNumAttributes(); i < n; ++i) {
-    uint16_t Form = AbbrevDecl->getFormByIndex(i);
-
-    // FIXME: Currently we're checking if this is less than the last
-    // entry in the fixed_form_sizes table, but this should be changed
-    // to use dynamic dispatch.
-    uint8_t FixedFormSize =
-        (Form < DW_FORM_ref_sig8) ? FixedFormSizes[Form] : 0;
-    if (FixedFormSize)
-      *OffsetPtr += FixedFormSize;
-    else if (!DWARFFormValue::skipValue(Form, DebugInfoData, OffsetPtr,
-                                        U)) {
-      // Restore the original offset.
-      *OffsetPtr = Offset;
-      return false;
-    }
-  }
-  return true;
-}
-
-bool DWARFDebugInfoEntryMinimal::extract(const DWARFUnit *U,
-                                         uint32_t *OffsetPtr) {
-  DataExtractor DebugInfoData = U->getDebugInfoExtractor();
-  const uint32_t UEndOffset = U->getNextUnitOffset();
-  Offset = *OffsetPtr;
-  if ((Offset >= UEndOffset) || !DebugInfoData.isValidOffset(Offset))
+  uint32_t UEndOffset = U->getNextUnitOffset();
+  if (Offset >= UEndOffset || !DebugInfoData.isValidOffset(Offset))
     return false;
   uint64_t AbbrCode = DebugInfoData.getULEB128(OffsetPtr);
   if (0 == AbbrCode) {
     // NULL debug tag entry.
-    AbbrevDecl = NULL;
+    AbbrevDecl = nullptr;
     return true;
   }
   AbbrevDecl = U->getAbbreviations()->getAbbreviationDeclaration(AbbrCode);
-  if (0 == AbbrevDecl) {
+  if (nullptr == AbbrevDecl) {
     // Restore the original offset.
     *OffsetPtr = Offset;
     return false;
   }
-  bool IsCompileUnitTag = (AbbrevDecl->getTag() == DW_TAG_compile_unit);
-  if (IsCompileUnitTag)
-    const_cast<DWARFUnit *>(U)->setBaseAddress(0);
+  ArrayRef<uint8_t> FixedFormSizes = DWARFFormValue::getFixedFormSizes(
+      U->getAddressByteSize(), U->getVersion());
+  assert(FixedFormSizes.size() > 0);
 
   // Skip all data in the .debug_info for the attributes
-  for (uint32_t i = 0, n = AbbrevDecl->getNumAttributes(); i < n; ++i) {
-    uint16_t Attr = AbbrevDecl->getAttrByIndex(i);
-    uint16_t Form = AbbrevDecl->getFormByIndex(i);
-
-    if (IsCompileUnitTag &&
-        ((Attr == DW_AT_entry_pc) || (Attr == DW_AT_low_pc))) {
-      DWARFFormValue FormValue(Form);
-      if (FormValue.extractValue(DebugInfoData, OffsetPtr, U)) {
-        if (Attr == DW_AT_low_pc || Attr == DW_AT_entry_pc)
-          const_cast<DWARFUnit *>(U)->setBaseAddress(FormValue.getUnsigned());
-      }
-    } else if (!DWARFFormValue::skipValue(Form, DebugInfoData, OffsetPtr, U)) {
+  for (const auto &AttrSpec : AbbrevDecl->attributes()) {
+    uint16_t Form = AttrSpec.Form;
+
+    uint8_t FixedFormSize =
+        (Form < FixedFormSizes.size()) ? FixedFormSizes[Form] : 0;
+    if (FixedFormSize)
+      *OffsetPtr += FixedFormSize;
+    else if (!DWARFFormValue::skipValue(Form, DebugInfoData, OffsetPtr, U)) {
       // Restore the original offset.
       *OffsetPtr = Offset;
       return false;
@@ -210,101 +201,143 @@ bool DWARFDebugInfoEntryMinimal::getAttributeValue(
 const char *DWARFDebugInfoEntryMinimal::getAttributeValueAsString(
     const DWARFUnit *U, const uint16_t Attr, const char *FailValue) const {
   DWARFFormValue FormValue;
-  if (getAttributeValue(U, Attr, FormValue))
-    return FormValue.getAsCString(U);
-  return FailValue;
+  if (!getAttributeValue(U, Attr, FormValue))
+    return FailValue;
+  Optional<const char *> Result = FormValue.getAsCString(U);
+  return Result.hasValue() ? Result.getValue() : FailValue;
 }
 
 uint64_t DWARFDebugInfoEntryMinimal::getAttributeValueAsAddress(
     const DWARFUnit *U, const uint16_t Attr, uint64_t FailValue) const {
   DWARFFormValue FormValue;
-  if (getAttributeValue(U, Attr, FormValue))
-    return FormValue.getAsAddress(U);
-  return FailValue;
+  if (!getAttributeValue(U, Attr, FormValue))
+    return FailValue;
+  Optional<uint64_t> Result = FormValue.getAsAddress(U);
+  return Result.hasValue() ? Result.getValue() : FailValue;
 }
 
-uint64_t DWARFDebugInfoEntryMinimal::getAttributeValueAsUnsigned(
+uint64_t DWARFDebugInfoEntryMinimal::getAttributeValueAsUnsignedConstant(
     const DWARFUnit *U, const uint16_t Attr, uint64_t FailValue) const {
   DWARFFormValue FormValue;
-  if (getAttributeValue(U, Attr, FormValue))
-    return FormValue.getUnsigned();
-  return FailValue;
+  if (!getAttributeValue(U, Attr, FormValue))
+    return FailValue;
+  Optional<uint64_t> Result = FormValue.getAsUnsignedConstant();
+  return Result.hasValue() ? Result.getValue() : FailValue;
 }
 
 uint64_t DWARFDebugInfoEntryMinimal::getAttributeValueAsReference(
     const DWARFUnit *U, const uint16_t Attr, uint64_t FailValue) const {
   DWARFFormValue FormValue;
-  if (getAttributeValue(U, Attr, FormValue))
-      return FormValue.getReference(U);
-  return FailValue;
+  if (!getAttributeValue(U, Attr, FormValue))
+    return FailValue;
+  Optional<uint64_t> Result = FormValue.getAsReference(U);
+  return Result.hasValue() ? Result.getValue() : FailValue;
+}
+
+uint64_t DWARFDebugInfoEntryMinimal::getAttributeValueAsSectionOffset(
+    const DWARFUnit *U, const uint16_t Attr, uint64_t FailValue) const {
+  DWARFFormValue FormValue;
+  if (!getAttributeValue(U, Attr, FormValue))
+    return FailValue;
+  Optional<uint64_t> Result = FormValue.getAsSectionOffset();
+  return Result.hasValue() ? Result.getValue() : FailValue;
+}
+
+uint64_t
+DWARFDebugInfoEntryMinimal::getRangesBaseAttribute(const DWARFUnit *U,
+                                                   uint64_t FailValue) const {
+  uint64_t Result =
+      getAttributeValueAsSectionOffset(U, DW_AT_ranges_base, -1ULL);
+  if (Result != -1ULL)
+    return Result;
+  return getAttributeValueAsSectionOffset(U, DW_AT_GNU_ranges_base, FailValue);
 }
 
 bool DWARFDebugInfoEntryMinimal::getLowAndHighPC(const DWARFUnit *U,
                                                  uint64_t &LowPC,
                                                  uint64_t &HighPC) const {
-  HighPC = -1ULL;
   LowPC = getAttributeValueAsAddress(U, DW_AT_low_pc, -1ULL);
-  // FIXME: Check if HighPC is of class constant (it has different semantics).
-  if (LowPC != -1ULL)
-    HighPC = getAttributeValueAsAddress(U, DW_AT_high_pc, -1ULL);
+  if (LowPC == -1ULL)
+    return false;
+  HighPC = getAttributeValueAsAddress(U, DW_AT_high_pc, -1ULL);
+  if (HighPC == -1ULL) {
+    // Since DWARF4, DW_AT_high_pc may also be of class constant, in which case
+    // it represents function size.
+    HighPC = getAttributeValueAsUnsignedConstant(U, DW_AT_high_pc, -1ULL);
+    if (HighPC != -1ULL)
+      HighPC += LowPC;
+  }
   return (HighPC != -1ULL);
 }
 
-void DWARFDebugInfoEntryMinimal::buildAddressRangeTable(
-    const DWARFUnit *U, DWARFDebugAranges *DebugAranges,
-    uint32_t UOffsetInAranges) const {
-  if (AbbrevDecl) {
-    if (isSubprogramDIE()) {
-      uint64_t LowPC, HighPC;
-      if (getLowAndHighPC(U, LowPC, HighPC))
-        DebugAranges->appendRange(UOffsetInAranges, LowPC, HighPC);
-      // FIXME: try to append ranges from .debug_ranges section.
-    }
+DWARFAddressRangesVector
+DWARFDebugInfoEntryMinimal::getAddressRanges(const DWARFUnit *U) const {
+  if (isNULL())
+    return DWARFAddressRangesVector();
+  // Single range specified by low/high PC.
+  uint64_t LowPC, HighPC;
+  if (getLowAndHighPC(U, LowPC, HighPC)) {
+    return DWARFAddressRangesVector(1, std::make_pair(LowPC, HighPC));
+  }
+  // Multiple ranges from .debug_ranges section.
+  uint32_t RangesOffset =
+      getAttributeValueAsSectionOffset(U, DW_AT_ranges, -1U);
+  if (RangesOffset != -1U) {
+    DWARFDebugRangeList RangeList;
+    if (U->extractRangeList(RangesOffset, RangeList))
+      return RangeList.getAbsoluteRanges(U->getBaseAddress());
+  }
+  return DWARFAddressRangesVector();
+}
 
-    const DWARFDebugInfoEntryMinimal *Child = getFirstChild();
-    while (Child) {
-      Child->buildAddressRangeTable(U, DebugAranges, UOffsetInAranges);
-      Child = Child->getSibling();
-    }
+void DWARFDebugInfoEntryMinimal::collectChildrenAddressRanges(
+    const DWARFUnit *U, DWARFAddressRangesVector& Ranges) const {
+  if (isNULL())
+    return;
+  if (isSubprogramDIE()) {
+    const auto &DIERanges = getAddressRanges(U);
+    Ranges.insert(Ranges.end(), DIERanges.begin(), DIERanges.end());
+  }
+
+  const DWARFDebugInfoEntryMinimal *Child = getFirstChild();
+  while (Child) {
+    Child->collectChildrenAddressRanges(U, Ranges);
+    Child = Child->getSibling();
   }
 }
 
 bool DWARFDebugInfoEntryMinimal::addressRangeContainsAddress(
     const DWARFUnit *U, const uint64_t Address) const {
-  if (isNULL())
-    return false;
-  uint64_t LowPC, HighPC;
-  if (getLowAndHighPC(U, LowPC, HighPC))
-    return (LowPC <= Address && Address <= HighPC);
-  // Try to get address ranges from .debug_ranges section.
-  uint32_t RangesOffset = getAttributeValueAsReference(U, DW_AT_ranges, -1U);
-  if (RangesOffset != -1U) {
-    DWARFDebugRangeList RangeList;
-    if (U->extractRangeList(RangesOffset, RangeList))
-      return RangeList.containsAddress(U->getBaseAddress(), Address);
+  for (const auto& R : getAddressRanges(U)) {
+    if (R.first <= Address && Address < R.second)
+      return true;
   }
   return false;
 }
 
 const char *
-DWARFDebugInfoEntryMinimal::getSubroutineName(const DWARFUnit *U) const {
-  if (!isSubroutineDIE())
-    return 0;
-  // Try to get mangled name if possible.
-  if (const char *name =
-      getAttributeValueAsString(U, DW_AT_MIPS_linkage_name, 0))
-    return name;
-  if (const char *name = getAttributeValueAsString(U, DW_AT_linkage_name, 0))
-    return name;
-  if (const char *name = getAttributeValueAsString(U, DW_AT_name, 0))
+DWARFDebugInfoEntryMinimal::getSubroutineName(const DWARFUnit *U,
+                                              FunctionNameKind Kind) const {
+  if (!isSubroutineDIE() || Kind == FunctionNameKind::None)
+    return nullptr;
+  // Try to get mangled name only if it was asked for.
+  if (Kind == FunctionNameKind::LinkageName) {
+    if (const char *name =
+            getAttributeValueAsString(U, DW_AT_MIPS_linkage_name, nullptr))
+      return name;
+    if (const char *name =
+            getAttributeValueAsString(U, DW_AT_linkage_name, nullptr))
+      return name;
+  }
+  if (const char *name = getAttributeValueAsString(U, DW_AT_name, nullptr))
     return name;
   // Try to get name from specification DIE.
   uint32_t spec_ref =
       getAttributeValueAsReference(U, DW_AT_specification, -1U);
   if (spec_ref != -1U) {
     DWARFDebugInfoEntryMinimal spec_die;
-    if (spec_die.extract(U, &spec_ref)) {
-      if (const char *name = spec_die.getSubroutineName(U))
+    if (const DWARFUnit *RefU = findUnitAndExtractFast(spec_die, U, &spec_ref)) {
+      if (const char *name = spec_die.getSubroutineName(RefU, Kind))
         return name;
     }
   }
@@ -313,21 +346,22 @@ DWARFDebugInfoEntryMinimal::getSubroutineName(const DWARFUnit *U) const {
       getAttributeValueAsReference(U, DW_AT_abstract_origin, -1U);
   if (abs_origin_ref != -1U) {
     DWARFDebugInfoEntryMinimal abs_origin_die;
-    if (abs_origin_die.extract(U, &abs_origin_ref)) {
-      if (const char *name = abs_origin_die.getSubroutineName(U))
+    if (const DWARFUnit *RefU = findUnitAndExtractFast(abs_origin_die, U,
+                                                       &abs_origin_ref)) {
+      if (const char *name = abs_origin_die.getSubroutineName(RefU, Kind))
         return name;
     }
   }
-  return 0;
+  return nullptr;
 }
 
 void DWARFDebugInfoEntryMinimal::getCallerFrame(const DWARFUnit *U,
                                                 uint32_t &CallFile,
                                                 uint32_t &CallLine,
                                                 uint32_t &CallColumn) const {
-  CallFile = getAttributeValueAsUnsigned(U, DW_AT_call_file, 0);
-  CallLine = getAttributeValueAsUnsigned(U, DW_AT_call_line, 0);
-  CallColumn = getAttributeValueAsUnsigned(U, DW_AT_call_column, 0);
+  CallFile = getAttributeValueAsUnsignedConstant(U, DW_AT_call_file, 0);
+  CallLine = getAttributeValueAsUnsignedConstant(U, DW_AT_call_line, 0);
+  CallColumn = getAttributeValueAsUnsignedConstant(U, DW_AT_call_column, 0);
 }
 
 DWARFDebugInfoEntryInlinedChain