Move DebugInfo to DebugInfo/DWARF.
In preparation for adding PDB support to LLVM, this moves the
DWARF parsing code to its own subdirectory under DebugInfo, and
renames LLVMDebugInfo to LLVMDebugInfoDWARF.
This is purely a mechanical / build system change.
Differential Revision: http://reviews.llvm.org/D7269
Reviewed by: Eric Christopher
llvm-svn: 227586
diff --git a/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
new file mode 100644
index 0000000..d4ecd69
--- /dev/null
+++ b/llvm/lib/DebugInfo/DWARF/DWARFUnit.cpp
@@ -0,0 +1,377 @@
+//===-- DWARFUnit.cpp -----------------------------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/DWARF/DWARFUnit.h"
+#include "llvm/DebugInfo/DWARF/DWARFContext.h"
+#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
+#include "llvm/Support/Dwarf.h"
+#include "llvm/Support/Path.h"
+#include <cstdio>
+
+using namespace llvm;
+using namespace dwarf;
+
+void DWARFUnitSectionBase::parse(DWARFContext &C, const DWARFSection &Section) {
+ parseImpl(C, Section, C.getDebugAbbrev(), C.getRangeSection(),
+ C.getStringSection(), StringRef(), C.getAddrSection(),
+ C.isLittleEndian());
+}
+
+void DWARFUnitSectionBase::parseDWO(DWARFContext &C,
+ const DWARFSection &DWOSection) {
+ parseImpl(C, DWOSection, C.getDebugAbbrevDWO(), C.getRangeDWOSection(),
+ C.getStringDWOSection(), C.getStringOffsetDWOSection(),
+ C.getAddrSection(), C.isLittleEndian());
+}
+
+DWARFUnit::DWARFUnit(DWARFContext &DC, const DWARFSection &Section,
+ const DWARFDebugAbbrev *DA, StringRef RS, StringRef SS,
+ StringRef SOS, StringRef AOS, bool LE,
+ const DWARFUnitSectionBase &UnitSection)
+ : Context(DC), InfoSection(Section), Abbrev(DA), RangeSection(RS),
+ StringSection(SS), StringOffsetSection(SOS), AddrOffsetSection(AOS),
+ isLittleEndian(LE), UnitSection(UnitSection) {
+ clear();
+}
+
+DWARFUnit::~DWARFUnit() {
+}
+
+bool DWARFUnit::getAddrOffsetSectionItem(uint32_t Index,
+ uint64_t &Result) const {
+ uint32_t Offset = AddrOffsetSectionBase + Index * AddrSize;
+ if (AddrOffsetSection.size() < Offset + AddrSize)
+ return false;
+ DataExtractor DA(AddrOffsetSection, isLittleEndian, AddrSize);
+ Result = DA.getAddress(&Offset);
+ return true;
+}
+
+bool DWARFUnit::getStringOffsetSectionItem(uint32_t Index,
+ uint32_t &Result) const {
+ // FIXME: string offset section entries are 8-byte for DWARF64.
+ const uint32_t ItemSize = 4;
+ uint32_t Offset = Index * ItemSize;
+ if (StringOffsetSection.size() < Offset + ItemSize)
+ return false;
+ DataExtractor DA(StringOffsetSection, isLittleEndian, 0);
+ Result = DA.getU32(&Offset);
+ return true;
+}
+
+bool DWARFUnit::extractImpl(DataExtractor debug_info, uint32_t *offset_ptr) {
+ Length = debug_info.getU32(offset_ptr);
+ Version = debug_info.getU16(offset_ptr);
+ uint64_t AbbrOffset = debug_info.getU32(offset_ptr);
+ AddrSize = debug_info.getU8(offset_ptr);
+
+ bool LengthOK = debug_info.isValidOffset(getNextUnitOffset() - 1);
+ bool VersionOK = DWARFContext::isSupportedVersion(Version);
+ bool AddrSizeOK = AddrSize == 4 || AddrSize == 8;
+
+ if (!LengthOK || !VersionOK || !AddrSizeOK)
+ return false;
+
+ Abbrevs = Abbrev->getAbbreviationDeclarationSet(AbbrOffset);
+ if (Abbrevs == nullptr)
+ return false;
+
+ return true;
+}
+
+bool DWARFUnit::extract(DataExtractor debug_info, uint32_t *offset_ptr) {
+ clear();
+
+ Offset = *offset_ptr;
+
+ if (debug_info.isValidOffset(*offset_ptr)) {
+ if (extractImpl(debug_info, offset_ptr))
+ return true;
+
+ // reset the offset to where we tried to parse from if anything went wrong
+ *offset_ptr = Offset;
+ }
+
+ return false;
+}
+
+bool DWARFUnit::extractRangeList(uint32_t RangeListOffset,
+ DWARFDebugRangeList &RangeList) const {
+ // Require that compile unit is extracted.
+ assert(DieArray.size() > 0);
+ DataExtractor RangesData(RangeSection, isLittleEndian, AddrSize);
+ uint32_t ActualRangeListOffset = RangeSectionBase + RangeListOffset;
+ return RangeList.extract(RangesData, &ActualRangeListOffset);
+}
+
+void DWARFUnit::clear() {
+ Offset = 0;
+ Length = 0;
+ Version = 0;
+ Abbrevs = nullptr;
+ AddrSize = 0;
+ BaseAddr = 0;
+ RangeSectionBase = 0;
+ AddrOffsetSectionBase = 0;
+ clearDIEs(false);
+ DWO.reset();
+}
+
+const char *DWARFUnit::getCompilationDir() {
+ extractDIEsIfNeeded(true);
+ if (DieArray.empty())
+ return nullptr;
+ return DieArray[0].getAttributeValueAsString(this, DW_AT_comp_dir, nullptr);
+}
+
+uint64_t DWARFUnit::getDWOId() {
+ extractDIEsIfNeeded(true);
+ const uint64_t FailValue = -1ULL;
+ if (DieArray.empty())
+ return FailValue;
+ return DieArray[0]
+ .getAttributeValueAsUnsignedConstant(this, DW_AT_GNU_dwo_id, FailValue);
+}
+
+void DWARFUnit::setDIERelations() {
+ if (DieArray.size() <= 1)
+ return;
+
+ std::vector<DWARFDebugInfoEntryMinimal *> ParentChain;
+ DWARFDebugInfoEntryMinimal *SiblingChain = nullptr;
+ for (auto &DIE : DieArray) {
+ if (SiblingChain) {
+ SiblingChain->setSibling(&DIE);
+ }
+ if (const DWARFAbbreviationDeclaration *AbbrDecl =
+ DIE.getAbbreviationDeclarationPtr()) {
+ // Normal DIE.
+ if (AbbrDecl->hasChildren()) {
+ ParentChain.push_back(&DIE);
+ SiblingChain = nullptr;
+ } else {
+ SiblingChain = &DIE;
+ }
+ } else {
+ // NULL entry terminates the sibling chain.
+ SiblingChain = ParentChain.back();
+ ParentChain.pop_back();
+ }
+ }
+ assert(SiblingChain == nullptr || SiblingChain == &DieArray[0]);
+ assert(ParentChain.empty());
+}
+
+void DWARFUnit::extractDIEsToVector(
+ bool AppendCUDie, bool AppendNonCUDies,
+ std::vector<DWARFDebugInfoEntryMinimal> &Dies) const {
+ if (!AppendCUDie && !AppendNonCUDies)
+ return;
+
+ // Set the offset to that of the first DIE and calculate the start of the
+ // next compilation unit header.
+ uint32_t DIEOffset = Offset + getHeaderSize();
+ uint32_t NextCUOffset = getNextUnitOffset();
+ DWARFDebugInfoEntryMinimal DIE;
+ uint32_t Depth = 0;
+ bool IsCUDie = true;
+
+ while (DIEOffset < NextCUOffset && DIE.extractFast(this, &DIEOffset)) {
+ if (IsCUDie) {
+ if (AppendCUDie)
+ Dies.push_back(DIE);
+ if (!AppendNonCUDies)
+ break;
+ // The average bytes per DIE entry has been seen to be
+ // around 14-20 so let's pre-reserve the needed memory for
+ // our DIE entries accordingly.
+ Dies.reserve(Dies.size() + getDebugInfoSize() / 14);
+ IsCUDie = false;
+ } else {
+ Dies.push_back(DIE);
+ }
+
+ if (const DWARFAbbreviationDeclaration *AbbrDecl =
+ DIE.getAbbreviationDeclarationPtr()) {
+ // Normal DIE
+ if (AbbrDecl->hasChildren())
+ ++Depth;
+ } else {
+ // NULL DIE.
+ if (Depth > 0)
+ --Depth;
+ if (Depth == 0)
+ break; // We are done with this compile unit!
+ }
+ }
+
+ // Give a little bit of info if we encounter corrupt DWARF (our offset
+ // should always terminate at or before the start of the next compilation
+ // unit header).
+ if (DIEOffset > NextCUOffset)
+ fprintf(stderr, "warning: DWARF compile unit extends beyond its "
+ "bounds cu 0x%8.8x at 0x%8.8x'\n", getOffset(), DIEOffset);
+}
+
+size_t DWARFUnit::extractDIEsIfNeeded(bool CUDieOnly) {
+ if ((CUDieOnly && DieArray.size() > 0) ||
+ DieArray.size() > 1)
+ return 0; // Already parsed.
+
+ bool HasCUDie = DieArray.size() > 0;
+ extractDIEsToVector(!HasCUDie, !CUDieOnly, DieArray);
+
+ if (DieArray.empty())
+ return 0;
+
+ // If CU DIE was just parsed, copy several attribute values from it.
+ if (!HasCUDie) {
+ uint64_t BaseAddr =
+ DieArray[0].getAttributeValueAsAddress(this, DW_AT_low_pc, -1ULL);
+ if (BaseAddr == -1ULL)
+ BaseAddr = DieArray[0].getAttributeValueAsAddress(this, DW_AT_entry_pc, 0);
+ setBaseAddress(BaseAddr);
+ AddrOffsetSectionBase = DieArray[0].getAttributeValueAsSectionOffset(
+ this, DW_AT_GNU_addr_base, 0);
+ RangeSectionBase = DieArray[0].getAttributeValueAsSectionOffset(
+ this, DW_AT_ranges_base, 0);
+ // Don't fall back to DW_AT_GNU_ranges_base: it should be ignored for
+ // skeleton CU DIE, so that DWARF users not aware of it are not broken.
+ }
+
+ setDIERelations();
+ return DieArray.size();
+}
+
+DWARFUnit::DWOHolder::DWOHolder(StringRef DWOPath)
+ : DWOFile(), DWOContext(), DWOU(nullptr) {
+ auto Obj = object::ObjectFile::createObjectFile(DWOPath);
+ if (!Obj)
+ return;
+ DWOFile = std::move(Obj.get());
+ DWOContext.reset(
+ cast<DWARFContext>(DIContext::getDWARFContext(*DWOFile.getBinary())));
+ if (DWOContext->getNumDWOCompileUnits() > 0)
+ DWOU = DWOContext->getDWOCompileUnitAtIndex(0);
+}
+
+bool DWARFUnit::parseDWO() {
+ if (DWO.get())
+ return false;
+ extractDIEsIfNeeded(true);
+ if (DieArray.empty())
+ return false;
+ const char *DWOFileName =
+ DieArray[0].getAttributeValueAsString(this, DW_AT_GNU_dwo_name, nullptr);
+ if (!DWOFileName)
+ return false;
+ const char *CompilationDir =
+ DieArray[0].getAttributeValueAsString(this, DW_AT_comp_dir, nullptr);
+ SmallString<16> AbsolutePath;
+ if (sys::path::is_relative(DWOFileName) && CompilationDir != nullptr) {
+ sys::path::append(AbsolutePath, CompilationDir);
+ }
+ sys::path::append(AbsolutePath, DWOFileName);
+ DWO = llvm::make_unique<DWOHolder>(AbsolutePath);
+ DWARFUnit *DWOCU = DWO->getUnit();
+ // Verify that compile unit in .dwo file is valid.
+ if (!DWOCU || DWOCU->getDWOId() != getDWOId()) {
+ DWO.reset();
+ return false;
+ }
+ // Share .debug_addr and .debug_ranges section with compile unit in .dwo
+ DWOCU->setAddrOffsetSection(AddrOffsetSection, AddrOffsetSectionBase);
+ uint32_t DWORangesBase = DieArray[0].getRangesBaseAttribute(this, 0);
+ DWOCU->setRangesSection(RangeSection, DWORangesBase);
+ return true;
+}
+
+void DWARFUnit::clearDIEs(bool KeepCUDie) {
+ if (DieArray.size() > (unsigned)KeepCUDie) {
+ // std::vectors never get any smaller when resized to a smaller size,
+ // or when clear() or erase() are called, the size will report that it
+ // is smaller, but the memory allocated remains intact (call capacity()
+ // to see this). So we need to create a temporary vector and swap the
+ // contents which will cause just the internal pointers to be swapped
+ // so that when temporary vector goes out of scope, it will destroy the
+ // contents.
+ std::vector<DWARFDebugInfoEntryMinimal> TmpArray;
+ DieArray.swap(TmpArray);
+ // Save at least the compile unit DIE
+ if (KeepCUDie)
+ DieArray.push_back(TmpArray.front());
+ }
+}
+
+void DWARFUnit::collectAddressRanges(DWARFAddressRangesVector &CURanges) {
+ // First, check if CU DIE describes address ranges for the unit.
+ const auto &CUDIERanges = getCompileUnitDIE()->getAddressRanges(this);
+ if (!CUDIERanges.empty()) {
+ CURanges.insert(CURanges.end(), CUDIERanges.begin(), CUDIERanges.end());
+ return;
+ }
+
+ // This function is usually called if there in no .debug_aranges section
+ // in order to produce a compile unit level set of address ranges that
+ // is accurate. If the DIEs weren't parsed, then we don't want all dies for
+ // all compile units to stay loaded when they weren't needed. So we can end
+ // up parsing the DWARF and then throwing them all away to keep memory usage
+ // down.
+ const bool ClearDIEs = extractDIEsIfNeeded(false) > 1;
+ DieArray[0].collectChildrenAddressRanges(this, CURanges);
+
+ // Collect address ranges from DIEs in .dwo if necessary.
+ bool DWOCreated = parseDWO();
+ if (DWO.get())
+ DWO->getUnit()->collectAddressRanges(CURanges);
+ if (DWOCreated)
+ DWO.reset();
+
+ // Keep memory down by clearing DIEs if this generate function
+ // caused them to be parsed.
+ if (ClearDIEs)
+ clearDIEs(true);
+}
+
+const DWARFDebugInfoEntryMinimal *
+DWARFUnit::getSubprogramForAddress(uint64_t Address) {
+ extractDIEsIfNeeded(false);
+ for (const DWARFDebugInfoEntryMinimal &DIE : DieArray) {
+ if (DIE.isSubprogramDIE() &&
+ DIE.addressRangeContainsAddress(this, Address)) {
+ return &DIE;
+ }
+ }
+ return nullptr;
+}
+
+DWARFDebugInfoEntryInlinedChain
+DWARFUnit::getInlinedChainForAddress(uint64_t Address) {
+ // First, find a subprogram that contains the given address (the root
+ // of inlined chain).
+ const DWARFUnit *ChainCU = nullptr;
+ const DWARFDebugInfoEntryMinimal *SubprogramDIE =
+ getSubprogramForAddress(Address);
+ if (SubprogramDIE) {
+ ChainCU = this;
+ } else {
+ // Try to look for subprogram DIEs in the DWO file.
+ parseDWO();
+ if (DWO.get()) {
+ SubprogramDIE = DWO->getUnit()->getSubprogramForAddress(Address);
+ if (SubprogramDIE)
+ ChainCU = DWO->getUnit();
+ }
+ }
+
+ // Get inlined chain rooted at this subprogram DIE.
+ if (!SubprogramDIE)
+ return DWARFDebugInfoEntryInlinedChain();
+ return SubprogramDIE->getInlinedChainForAddress(ChainCU, Address);
+}