635 lines
23 KiB
C++
635 lines
23 KiB
C++
//===- MCCodeView.h - Machine Code CodeView support -------------*- C++ -*-===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// Holds state from .cv_file and .cv_loc directives for later emission.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/MC/MCCodeView.h"
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#include "llvm/ADT/STLExtras.h"
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#include "llvm/ADT/StringExtras.h"
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#include "llvm/DebugInfo/CodeView/CodeView.h"
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#include "llvm/DebugInfo/CodeView/Line.h"
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#include "llvm/DebugInfo/CodeView/SymbolRecord.h"
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#include "llvm/MC/MCAsmLayout.h"
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#include "llvm/MC/MCContext.h"
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#include "llvm/MC/MCObjectStreamer.h"
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#include "llvm/MC/MCValue.h"
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#include "llvm/Support/EndianStream.h"
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using namespace llvm;
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using namespace llvm::codeview;
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CodeViewContext::CodeViewContext() {}
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CodeViewContext::~CodeViewContext() {
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// If someone inserted strings into the string table but never actually
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// emitted them somewhere, clean up the fragment.
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if (!InsertedStrTabFragment)
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delete StrTabFragment;
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}
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/// This is a valid number for use with .cv_loc if we've already seen a .cv_file
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/// for it.
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bool CodeViewContext::isValidFileNumber(unsigned FileNumber) const {
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unsigned Idx = FileNumber - 1;
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if (Idx < Files.size())
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return Files[Idx].Assigned;
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return false;
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}
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bool CodeViewContext::addFile(MCStreamer &OS, unsigned FileNumber,
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StringRef Filename,
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ArrayRef<uint8_t> ChecksumBytes,
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uint8_t ChecksumKind) {
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assert(FileNumber > 0);
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auto FilenameOffset = addToStringTable(Filename);
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Filename = FilenameOffset.first;
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unsigned Idx = FileNumber - 1;
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if (Idx >= Files.size())
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Files.resize(Idx + 1);
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if (Filename.empty())
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Filename = "<stdin>";
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if (Files[Idx].Assigned)
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return false;
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FilenameOffset = addToStringTable(Filename);
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Filename = FilenameOffset.first;
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unsigned Offset = FilenameOffset.second;
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auto ChecksumOffsetSymbol =
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OS.getContext().createTempSymbol("checksum_offset", false);
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Files[Idx].StringTableOffset = Offset;
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Files[Idx].ChecksumTableOffset = ChecksumOffsetSymbol;
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Files[Idx].Assigned = true;
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Files[Idx].Checksum = ChecksumBytes;
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Files[Idx].ChecksumKind = ChecksumKind;
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return true;
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}
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bool CodeViewContext::recordFunctionId(unsigned FuncId) {
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if (FuncId >= Functions.size())
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Functions.resize(FuncId + 1);
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// Return false if this function info was already allocated.
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if (!Functions[FuncId].isUnallocatedFunctionInfo())
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return false;
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// Mark this as an allocated normal function, and leave the rest alone.
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Functions[FuncId].ParentFuncIdPlusOne = MCCVFunctionInfo::FunctionSentinel;
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return true;
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}
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bool CodeViewContext::recordInlinedCallSiteId(unsigned FuncId, unsigned IAFunc,
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unsigned IAFile, unsigned IALine,
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unsigned IACol) {
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if (FuncId >= Functions.size())
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Functions.resize(FuncId + 1);
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// Return false if this function info was already allocated.
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if (!Functions[FuncId].isUnallocatedFunctionInfo())
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return false;
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MCCVFunctionInfo::LineInfo InlinedAt;
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InlinedAt.File = IAFile;
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InlinedAt.Line = IALine;
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InlinedAt.Col = IACol;
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// Mark this as an inlined call site and record call site line info.
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MCCVFunctionInfo *Info = &Functions[FuncId];
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Info->ParentFuncIdPlusOne = IAFunc + 1;
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Info->InlinedAt = InlinedAt;
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// Walk up the call chain adding this function id to the InlinedAtMap of all
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// transitive callers until we hit a real function.
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while (Info->isInlinedCallSite()) {
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InlinedAt = Info->InlinedAt;
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Info = getCVFunctionInfo(Info->getParentFuncId());
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Info->InlinedAtMap[FuncId] = InlinedAt;
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}
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return true;
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}
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MCDataFragment *CodeViewContext::getStringTableFragment() {
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if (!StrTabFragment) {
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StrTabFragment = new MCDataFragment();
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// Start a new string table out with a null byte.
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StrTabFragment->getContents().push_back('\0');
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}
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return StrTabFragment;
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}
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std::pair<StringRef, unsigned> CodeViewContext::addToStringTable(StringRef S) {
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SmallVectorImpl<char> &Contents = getStringTableFragment()->getContents();
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auto Insertion =
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StringTable.insert(std::make_pair(S, unsigned(Contents.size())));
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// Return the string from the table, since it is stable.
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std::pair<StringRef, unsigned> Ret =
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std::make_pair(Insertion.first->first(), Insertion.first->second);
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if (Insertion.second) {
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// The string map key is always null terminated.
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Contents.append(Ret.first.begin(), Ret.first.end() + 1);
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}
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return Ret;
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}
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unsigned CodeViewContext::getStringTableOffset(StringRef S) {
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// A string table offset of zero is always the empty string.
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if (S.empty())
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return 0;
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auto I = StringTable.find(S);
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assert(I != StringTable.end());
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return I->second;
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}
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void CodeViewContext::emitStringTable(MCObjectStreamer &OS) {
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MCContext &Ctx = OS.getContext();
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MCSymbol *StringBegin = Ctx.createTempSymbol("strtab_begin", false),
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*StringEnd = Ctx.createTempSymbol("strtab_end", false);
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OS.EmitIntValue(unsigned(DebugSubsectionKind::StringTable), 4);
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OS.emitAbsoluteSymbolDiff(StringEnd, StringBegin, 4);
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OS.EmitLabel(StringBegin);
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// Put the string table data fragment here, if we haven't already put it
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// somewhere else. If somebody wants two string tables in their .s file, one
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// will just be empty.
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if (!InsertedStrTabFragment) {
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OS.insert(getStringTableFragment());
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InsertedStrTabFragment = true;
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}
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OS.EmitValueToAlignment(4, 0);
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OS.EmitLabel(StringEnd);
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}
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void CodeViewContext::emitFileChecksums(MCObjectStreamer &OS) {
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// Do nothing if there are no file checksums. Microsoft's linker rejects empty
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// CodeView substreams.
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if (Files.empty())
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return;
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MCContext &Ctx = OS.getContext();
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MCSymbol *FileBegin = Ctx.createTempSymbol("filechecksums_begin", false),
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*FileEnd = Ctx.createTempSymbol("filechecksums_end", false);
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OS.EmitIntValue(unsigned(DebugSubsectionKind::FileChecksums), 4);
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OS.emitAbsoluteSymbolDiff(FileEnd, FileBegin, 4);
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OS.EmitLabel(FileBegin);
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unsigned CurrentOffset = 0;
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// Emit an array of FileChecksum entries. We index into this table using the
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// user-provided file number. Each entry may be a variable number of bytes
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// determined by the checksum kind and size.
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for (auto File : Files) {
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OS.EmitAssignment(File.ChecksumTableOffset,
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MCConstantExpr::create(CurrentOffset, Ctx));
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CurrentOffset += 4; // String table offset.
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if (!File.ChecksumKind) {
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CurrentOffset +=
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4; // One byte each for checksum size and kind, then align to 4 bytes.
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} else {
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CurrentOffset += 2; // One byte each for checksum size and kind.
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CurrentOffset += File.Checksum.size();
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CurrentOffset = alignTo(CurrentOffset, 4);
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}
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OS.EmitIntValue(File.StringTableOffset, 4);
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if (!File.ChecksumKind) {
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// There is no checksum. Therefore zero the next two fields and align
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// back to 4 bytes.
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OS.EmitIntValue(0, 4);
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continue;
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}
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OS.EmitIntValue(static_cast<uint8_t>(File.Checksum.size()), 1);
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OS.EmitIntValue(File.ChecksumKind, 1);
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OS.EmitBytes(toStringRef(File.Checksum));
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OS.EmitValueToAlignment(4);
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}
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OS.EmitLabel(FileEnd);
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ChecksumOffsetsAssigned = true;
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}
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// Output checksum table offset of the given file number. It is possible that
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// not all files have been registered yet, and so the offset cannot be
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// calculated. In this case a symbol representing the offset is emitted, and
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// the value of this symbol will be fixed up at a later time.
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void CodeViewContext::emitFileChecksumOffset(MCObjectStreamer &OS,
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unsigned FileNo) {
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unsigned Idx = FileNo - 1;
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if (Idx >= Files.size())
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Files.resize(Idx + 1);
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if (ChecksumOffsetsAssigned) {
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OS.EmitSymbolValue(Files[Idx].ChecksumTableOffset, 4);
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return;
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}
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const MCSymbolRefExpr *SRE =
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MCSymbolRefExpr::create(Files[Idx].ChecksumTableOffset, OS.getContext());
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OS.EmitValueImpl(SRE, 4);
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}
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void CodeViewContext::emitLineTableForFunction(MCObjectStreamer &OS,
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unsigned FuncId,
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const MCSymbol *FuncBegin,
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const MCSymbol *FuncEnd) {
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MCContext &Ctx = OS.getContext();
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MCSymbol *LineBegin = Ctx.createTempSymbol("linetable_begin", false),
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*LineEnd = Ctx.createTempSymbol("linetable_end", false);
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OS.EmitIntValue(unsigned(DebugSubsectionKind::Lines), 4);
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OS.emitAbsoluteSymbolDiff(LineEnd, LineBegin, 4);
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OS.EmitLabel(LineBegin);
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OS.EmitCOFFSecRel32(FuncBegin, /*Offset=*/0);
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OS.EmitCOFFSectionIndex(FuncBegin);
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// Actual line info.
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std::vector<MCCVLineEntry> Locs = getFunctionLineEntries(FuncId);
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bool HaveColumns = any_of(Locs, [](const MCCVLineEntry &LineEntry) {
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return LineEntry.getColumn() != 0;
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});
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OS.EmitIntValue(HaveColumns ? int(LF_HaveColumns) : 0, 2);
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OS.emitAbsoluteSymbolDiff(FuncEnd, FuncBegin, 4);
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for (auto I = Locs.begin(), E = Locs.end(); I != E;) {
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// Emit a file segment for the run of locations that share a file id.
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unsigned CurFileNum = I->getFileNum();
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auto FileSegEnd =
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std::find_if(I, E, [CurFileNum](const MCCVLineEntry &Loc) {
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return Loc.getFileNum() != CurFileNum;
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});
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unsigned EntryCount = FileSegEnd - I;
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OS.AddComment(
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"Segment for file '" +
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Twine(getStringTableFragment()
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->getContents()[Files[CurFileNum - 1].StringTableOffset]) +
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"' begins");
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OS.EmitCVFileChecksumOffsetDirective(CurFileNum);
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OS.EmitIntValue(EntryCount, 4);
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uint32_t SegmentSize = 12;
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SegmentSize += 8 * EntryCount;
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if (HaveColumns)
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SegmentSize += 4 * EntryCount;
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OS.EmitIntValue(SegmentSize, 4);
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for (auto J = I; J != FileSegEnd; ++J) {
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OS.emitAbsoluteSymbolDiff(J->getLabel(), FuncBegin, 4);
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unsigned LineData = J->getLine();
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if (J->isStmt())
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LineData |= LineInfo::StatementFlag;
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OS.EmitIntValue(LineData, 4);
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}
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if (HaveColumns) {
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for (auto J = I; J != FileSegEnd; ++J) {
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OS.EmitIntValue(J->getColumn(), 2);
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OS.EmitIntValue(0, 2);
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}
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}
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I = FileSegEnd;
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}
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OS.EmitLabel(LineEnd);
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}
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static bool compressAnnotation(uint32_t Data, SmallVectorImpl<char> &Buffer) {
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if (isUInt<7>(Data)) {
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Buffer.push_back(Data);
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return true;
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}
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if (isUInt<14>(Data)) {
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Buffer.push_back((Data >> 8) | 0x80);
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Buffer.push_back(Data & 0xff);
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return true;
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}
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if (isUInt<29>(Data)) {
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Buffer.push_back((Data >> 24) | 0xC0);
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Buffer.push_back((Data >> 16) & 0xff);
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Buffer.push_back((Data >> 8) & 0xff);
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Buffer.push_back(Data & 0xff);
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return true;
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}
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return false;
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}
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static bool compressAnnotation(BinaryAnnotationsOpCode Annotation,
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SmallVectorImpl<char> &Buffer) {
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return compressAnnotation(static_cast<uint32_t>(Annotation), Buffer);
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}
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static uint32_t encodeSignedNumber(uint32_t Data) {
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if (Data >> 31)
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return ((-Data) << 1) | 1;
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return Data << 1;
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}
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void CodeViewContext::emitInlineLineTableForFunction(MCObjectStreamer &OS,
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unsigned PrimaryFunctionId,
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unsigned SourceFileId,
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unsigned SourceLineNum,
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const MCSymbol *FnStartSym,
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const MCSymbol *FnEndSym) {
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// Create and insert a fragment into the current section that will be encoded
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// later.
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new MCCVInlineLineTableFragment(PrimaryFunctionId, SourceFileId,
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SourceLineNum, FnStartSym, FnEndSym,
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OS.getCurrentSectionOnly());
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}
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void CodeViewContext::emitDefRange(
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MCObjectStreamer &OS,
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ArrayRef<std::pair<const MCSymbol *, const MCSymbol *>> Ranges,
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StringRef FixedSizePortion) {
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// Create and insert a fragment into the current section that will be encoded
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// later.
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new MCCVDefRangeFragment(Ranges, FixedSizePortion,
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OS.getCurrentSectionOnly());
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}
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static unsigned computeLabelDiff(MCAsmLayout &Layout, const MCSymbol *Begin,
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const MCSymbol *End) {
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MCContext &Ctx = Layout.getAssembler().getContext();
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MCSymbolRefExpr::VariantKind Variant = MCSymbolRefExpr::VK_None;
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const MCExpr *BeginRef = MCSymbolRefExpr::create(Begin, Variant, Ctx),
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*EndRef = MCSymbolRefExpr::create(End, Variant, Ctx);
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const MCExpr *AddrDelta =
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MCBinaryExpr::create(MCBinaryExpr::Sub, EndRef, BeginRef, Ctx);
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int64_t Result;
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bool Success = AddrDelta->evaluateKnownAbsolute(Result, Layout);
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assert(Success && "failed to evaluate label difference as absolute");
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(void)Success;
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assert(Result >= 0 && "negative label difference requested");
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assert(Result < UINT_MAX && "label difference greater than 2GB");
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return unsigned(Result);
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}
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void CodeViewContext::encodeInlineLineTable(MCAsmLayout &Layout,
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MCCVInlineLineTableFragment &Frag) {
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size_t LocBegin;
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size_t LocEnd;
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std::tie(LocBegin, LocEnd) = getLineExtent(Frag.SiteFuncId);
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// Include all child inline call sites in our .cv_loc extent.
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MCCVFunctionInfo *SiteInfo = getCVFunctionInfo(Frag.SiteFuncId);
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for (auto &KV : SiteInfo->InlinedAtMap) {
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unsigned ChildId = KV.first;
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auto Extent = getLineExtent(ChildId);
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LocBegin = std::min(LocBegin, Extent.first);
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LocEnd = std::max(LocEnd, Extent.second);
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}
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if (LocBegin >= LocEnd)
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return;
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ArrayRef<MCCVLineEntry> Locs = getLinesForExtent(LocBegin, LocEnd);
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if (Locs.empty())
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return;
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// Make an artificial start location using the function start and the inlinee
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// lines start location information. All deltas start relative to this
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// location.
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MCCVLineEntry StartLoc(Frag.getFnStartSym(), MCCVLoc(Locs.front()));
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StartLoc.setFileNum(Frag.StartFileId);
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StartLoc.setLine(Frag.StartLineNum);
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bool HaveOpenRange = false;
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const MCSymbol *LastLabel = Frag.getFnStartSym();
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MCCVFunctionInfo::LineInfo LastSourceLoc, CurSourceLoc;
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LastSourceLoc.File = Frag.StartFileId;
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LastSourceLoc.Line = Frag.StartLineNum;
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SmallVectorImpl<char> &Buffer = Frag.getContents();
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Buffer.clear(); // Clear old contents if we went through relaxation.
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for (const MCCVLineEntry &Loc : Locs) {
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// Exit early if our line table would produce an oversized InlineSiteSym
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// record. Account for the ChangeCodeLength annotation emitted after the
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// loop ends.
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constexpr uint32_t InlineSiteSize = 12;
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constexpr uint32_t AnnotationSize = 8;
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size_t MaxBufferSize = MaxRecordLength - InlineSiteSize - AnnotationSize;
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if (Buffer.size() >= MaxBufferSize)
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break;
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if (Loc.getFunctionId() == Frag.SiteFuncId) {
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CurSourceLoc.File = Loc.getFileNum();
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CurSourceLoc.Line = Loc.getLine();
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} else {
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auto I = SiteInfo->InlinedAtMap.find(Loc.getFunctionId());
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if (I != SiteInfo->InlinedAtMap.end()) {
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// This .cv_loc is from a child inline call site. Use the source
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// location of the inlined call site instead of the .cv_loc directive
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// source location.
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CurSourceLoc = I->second;
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} else {
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// We've hit a cv_loc not attributed to this inline call site. Use this
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// label to end the PC range.
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if (HaveOpenRange) {
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unsigned Length = computeLabelDiff(Layout, LastLabel, Loc.getLabel());
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compressAnnotation(BinaryAnnotationsOpCode::ChangeCodeLength, Buffer);
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compressAnnotation(Length, Buffer);
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LastLabel = Loc.getLabel();
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}
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HaveOpenRange = false;
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continue;
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}
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}
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// Skip this .cv_loc if we have an open range and this isn't a meaningful
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// source location update. The current table format does not support column
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// info, so we can skip updates for those.
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if (HaveOpenRange && CurSourceLoc.File == LastSourceLoc.File &&
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CurSourceLoc.Line == LastSourceLoc.Line)
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continue;
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HaveOpenRange = true;
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if (CurSourceLoc.File != LastSourceLoc.File) {
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unsigned FileOffset = static_cast<const MCConstantExpr *>(
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Files[CurSourceLoc.File - 1]
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.ChecksumTableOffset->getVariableValue())
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->getValue();
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compressAnnotation(BinaryAnnotationsOpCode::ChangeFile, Buffer);
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compressAnnotation(FileOffset, Buffer);
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}
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int LineDelta = CurSourceLoc.Line - LastSourceLoc.Line;
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unsigned EncodedLineDelta = encodeSignedNumber(LineDelta);
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unsigned CodeDelta = computeLabelDiff(Layout, LastLabel, Loc.getLabel());
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if (CodeDelta == 0 && LineDelta != 0) {
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compressAnnotation(BinaryAnnotationsOpCode::ChangeLineOffset, Buffer);
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compressAnnotation(EncodedLineDelta, Buffer);
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} else if (EncodedLineDelta < 0x8 && CodeDelta <= 0xf) {
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// The ChangeCodeOffsetAndLineOffset combination opcode is used when the
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// encoded line delta uses 3 or fewer set bits and the code offset fits
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// in one nibble.
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unsigned Operand = (EncodedLineDelta << 4) | CodeDelta;
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compressAnnotation(BinaryAnnotationsOpCode::ChangeCodeOffsetAndLineOffset,
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Buffer);
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compressAnnotation(Operand, Buffer);
|
|
} else {
|
|
// Otherwise use the separate line and code deltas.
|
|
if (LineDelta != 0) {
|
|
compressAnnotation(BinaryAnnotationsOpCode::ChangeLineOffset, Buffer);
|
|
compressAnnotation(EncodedLineDelta, Buffer);
|
|
}
|
|
compressAnnotation(BinaryAnnotationsOpCode::ChangeCodeOffset, Buffer);
|
|
compressAnnotation(CodeDelta, Buffer);
|
|
}
|
|
|
|
LastLabel = Loc.getLabel();
|
|
LastSourceLoc = CurSourceLoc;
|
|
}
|
|
|
|
assert(HaveOpenRange);
|
|
|
|
unsigned EndSymLength =
|
|
computeLabelDiff(Layout, LastLabel, Frag.getFnEndSym());
|
|
unsigned LocAfterLength = ~0U;
|
|
ArrayRef<MCCVLineEntry> LocAfter = getLinesForExtent(LocEnd, LocEnd + 1);
|
|
if (!LocAfter.empty()) {
|
|
// Only try to compute this difference if we're in the same section.
|
|
const MCCVLineEntry &Loc = LocAfter[0];
|
|
if (&Loc.getLabel()->getSection(false) == &LastLabel->getSection(false))
|
|
LocAfterLength = computeLabelDiff(Layout, LastLabel, Loc.getLabel());
|
|
}
|
|
|
|
compressAnnotation(BinaryAnnotationsOpCode::ChangeCodeLength, Buffer);
|
|
compressAnnotation(std::min(EndSymLength, LocAfterLength), Buffer);
|
|
}
|
|
|
|
void CodeViewContext::encodeDefRange(MCAsmLayout &Layout,
|
|
MCCVDefRangeFragment &Frag) {
|
|
MCContext &Ctx = Layout.getAssembler().getContext();
|
|
SmallVectorImpl<char> &Contents = Frag.getContents();
|
|
Contents.clear();
|
|
SmallVectorImpl<MCFixup> &Fixups = Frag.getFixups();
|
|
Fixups.clear();
|
|
raw_svector_ostream OS(Contents);
|
|
|
|
// Compute all the sizes up front.
|
|
SmallVector<std::pair<unsigned, unsigned>, 4> GapAndRangeSizes;
|
|
const MCSymbol *LastLabel = nullptr;
|
|
for (std::pair<const MCSymbol *, const MCSymbol *> Range : Frag.getRanges()) {
|
|
unsigned GapSize =
|
|
LastLabel ? computeLabelDiff(Layout, LastLabel, Range.first) : 0;
|
|
unsigned RangeSize = computeLabelDiff(Layout, Range.first, Range.second);
|
|
GapAndRangeSizes.push_back({GapSize, RangeSize});
|
|
LastLabel = Range.second;
|
|
}
|
|
|
|
// Write down each range where the variable is defined.
|
|
for (size_t I = 0, E = Frag.getRanges().size(); I != E;) {
|
|
// If the range size of multiple consecutive ranges is under the max,
|
|
// combine the ranges and emit some gaps.
|
|
const MCSymbol *RangeBegin = Frag.getRanges()[I].first;
|
|
unsigned RangeSize = GapAndRangeSizes[I].second;
|
|
size_t J = I + 1;
|
|
for (; J != E; ++J) {
|
|
unsigned GapAndRangeSize = GapAndRangeSizes[J].first + GapAndRangeSizes[J].second;
|
|
if (RangeSize + GapAndRangeSize > MaxDefRange)
|
|
break;
|
|
RangeSize += GapAndRangeSize;
|
|
}
|
|
unsigned NumGaps = J - I - 1;
|
|
|
|
support::endian::Writer<support::little> LEWriter(OS);
|
|
|
|
unsigned Bias = 0;
|
|
// We must split the range into chunks of MaxDefRange, this is a fundamental
|
|
// limitation of the file format.
|
|
do {
|
|
uint16_t Chunk = std::min((uint32_t)MaxDefRange, RangeSize);
|
|
|
|
const MCSymbolRefExpr *SRE = MCSymbolRefExpr::create(RangeBegin, Ctx);
|
|
const MCBinaryExpr *BE =
|
|
MCBinaryExpr::createAdd(SRE, MCConstantExpr::create(Bias, Ctx), Ctx);
|
|
MCValue Res;
|
|
BE->evaluateAsRelocatable(Res, &Layout, /*Fixup=*/nullptr);
|
|
|
|
// Each record begins with a 2-byte number indicating how large the record
|
|
// is.
|
|
StringRef FixedSizePortion = Frag.getFixedSizePortion();
|
|
// Our record is a fixed sized prefix and a LocalVariableAddrRange that we
|
|
// are artificially constructing.
|
|
size_t RecordSize = FixedSizePortion.size() +
|
|
sizeof(LocalVariableAddrRange) + 4 * NumGaps;
|
|
// Write out the record size.
|
|
LEWriter.write<uint16_t>(RecordSize);
|
|
// Write out the fixed size prefix.
|
|
OS << FixedSizePortion;
|
|
// Make space for a fixup that will eventually have a section relative
|
|
// relocation pointing at the offset where the variable becomes live.
|
|
Fixups.push_back(MCFixup::create(Contents.size(), BE, FK_SecRel_4));
|
|
LEWriter.write<uint32_t>(0); // Fixup for code start.
|
|
// Make space for a fixup that will record the section index for the code.
|
|
Fixups.push_back(MCFixup::create(Contents.size(), BE, FK_SecRel_2));
|
|
LEWriter.write<uint16_t>(0); // Fixup for section index.
|
|
// Write down the range's extent.
|
|
LEWriter.write<uint16_t>(Chunk);
|
|
|
|
// Move on to the next range.
|
|
Bias += Chunk;
|
|
RangeSize -= Chunk;
|
|
} while (RangeSize > 0);
|
|
|
|
// Emit the gaps afterwards.
|
|
assert((NumGaps == 0 || Bias <= MaxDefRange) &&
|
|
"large ranges should not have gaps");
|
|
unsigned GapStartOffset = GapAndRangeSizes[I].second;
|
|
for (++I; I != J; ++I) {
|
|
unsigned GapSize, RangeSize;
|
|
assert(I < GapAndRangeSizes.size());
|
|
std::tie(GapSize, RangeSize) = GapAndRangeSizes[I];
|
|
LEWriter.write<uint16_t>(GapStartOffset);
|
|
LEWriter.write<uint16_t>(GapSize);
|
|
GapStartOffset += GapSize + RangeSize;
|
|
}
|
|
}
|
|
}
|
|
|
|
//
|
|
// This is called when an instruction is assembled into the specified section
|
|
// and if there is information from the last .cv_loc directive that has yet to have
|
|
// a line entry made for it is made.
|
|
//
|
|
void MCCVLineEntry::Make(MCObjectStreamer *MCOS) {
|
|
CodeViewContext &CVC = MCOS->getContext().getCVContext();
|
|
if (!CVC.getCVLocSeen())
|
|
return;
|
|
|
|
// Create a symbol at in the current section for use in the line entry.
|
|
MCSymbol *LineSym = MCOS->getContext().createTempSymbol();
|
|
// Set the value of the symbol to use for the MCCVLineEntry.
|
|
MCOS->EmitLabel(LineSym);
|
|
|
|
// Get the current .loc info saved in the context.
|
|
const MCCVLoc &CVLoc = CVC.getCurrentCVLoc();
|
|
|
|
// Create a (local) line entry with the symbol and the current .loc info.
|
|
MCCVLineEntry LineEntry(LineSym, CVLoc);
|
|
|
|
// clear CVLocSeen saying the current .loc info is now used.
|
|
CVC.clearCVLocSeen();
|
|
|
|
// Add the line entry to this section's entries.
|
|
CVC.addLineEntry(LineEntry);
|
|
}
|