diff options
Diffstat (limited to 'contrib/llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.cpp')
-rw-r--r-- | contrib/llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.cpp | 74 |
1 files changed, 74 insertions, 0 deletions
diff --git a/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.cpp b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.cpp new file mode 100644 index 0000000..2066f74 --- /dev/null +++ b/contrib/llvm/lib/CodeGen/AsmPrinter/DwarfStringPool.cpp @@ -0,0 +1,74 @@ +//===-- llvm/CodeGen/DwarfStringPool.cpp - Dwarf Debug Framework ----------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#include "DwarfStringPool.h" +#include "llvm/CodeGen/AsmPrinter.h" +#include "llvm/MC/MCAsmInfo.h" +#include "llvm/MC/MCStreamer.h" + +using namespace llvm; + +DwarfStringPool::DwarfStringPool(BumpPtrAllocator &A, AsmPrinter &Asm, + StringRef Prefix) + : Pool(A), Prefix(Prefix), + ShouldCreateSymbols(Asm.MAI->doesDwarfUseRelocationsAcrossSections()) {} + +DwarfStringPool::EntryRef DwarfStringPool::getEntry(AsmPrinter &Asm, + StringRef Str) { + auto I = Pool.insert(std::make_pair(Str, EntryTy())); + if (I.second) { + auto &Entry = I.first->second; + Entry.Index = Pool.size() - 1; + Entry.Offset = NumBytes; + Entry.Symbol = ShouldCreateSymbols ? Asm.createTempSymbol(Prefix) : nullptr; + + NumBytes += Str.size() + 1; + assert(NumBytes > Entry.Offset && "Unexpected overflow"); + } + return EntryRef(*I.first); +} + +void DwarfStringPool::emit(AsmPrinter &Asm, MCSection *StrSection, + MCSection *OffsetSection) { + if (Pool.empty()) + return; + + // Start the dwarf str section. + Asm.OutStreamer->SwitchSection(StrSection); + + // Get all of the string pool entries and put them in an array by their ID so + // we can sort them. + SmallVector<const StringMapEntry<EntryTy> *, 64> Entries(Pool.size()); + + for (const auto &E : Pool) + Entries[E.getValue().Index] = &E; + + for (const auto &Entry : Entries) { + assert(ShouldCreateSymbols == static_cast<bool>(Entry->getValue().Symbol) && + "Mismatch between setting and entry"); + + // Emit a label for reference from debug information entries. + if (ShouldCreateSymbols) + Asm.OutStreamer->EmitLabel(Entry->getValue().Symbol); + + // Emit the string itself with a terminating null byte. + Asm.OutStreamer->AddComment("string offset=" + + Twine(Entry->getValue().Offset)); + Asm.OutStreamer->EmitBytes( + StringRef(Entry->getKeyData(), Entry->getKeyLength() + 1)); + } + + // If we've got an offset section go ahead and emit that now as well. + if (OffsetSection) { + Asm.OutStreamer->SwitchSection(OffsetSection); + unsigned size = 4; // FIXME: DWARF64 is 8. + for (const auto &Entry : Entries) + Asm.OutStreamer->EmitIntValue(Entry->getValue().Offset, size); + } +} |