llvm-6502/lib/CodeGen/AsmPrinter/DwarfStringPool.h
Duncan P. N. Exon Smith 518dcb905e AsmPrinter: Avoid creating symbols in DwarfStringPool
Stop creating symbols we don't need in `DwarfStringPool`.  The consumers
only call `DwarfStringPoolEntryRef::getSymbol()` when DWARF is
relocatable, so this just stops creating the unused symbols when it's
not.  This drops memory usage from 851 MB to 845 MB, around 0.7%.

(I'm looking at `llc` memory usage on `verify-uselistorder.lto.opt.bc`;
see r236629 for details.)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@238122 91177308-0d34-0410-b5e6-96231b3b80d8
2015-05-24 16:58:59 +00:00

50 lines
1.4 KiB
C++

//===-- llvm/CodeGen/DwarfStringPool.h - Dwarf Debug Framework -*- C++ -*--===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DWARFSTRINGPOOL_H
#define LLVM_LIB_CODEGEN_ASMPRINTER_DWARFSTRINGPOOL_H
#include "llvm/ADT/StringMap.h"
#include "llvm/CodeGen/DwarfStringPoolEntry.h"
#include "llvm/Support/Allocator.h"
#include <utility>
namespace llvm {
class AsmPrinter;
class MCSymbol;
class MCSection;
class StringRef;
// Collection of strings for this unit and assorted symbols.
// A String->Symbol mapping of strings used by indirect
// references.
class DwarfStringPool {
typedef DwarfStringPoolEntry EntryTy;
StringMap<EntryTy, BumpPtrAllocator &> Pool;
StringRef Prefix;
unsigned NumBytes = 0;
bool ShouldCreateSymbols;
public:
typedef DwarfStringPoolEntryRef EntryRef;
DwarfStringPool(BumpPtrAllocator &A, AsmPrinter &Asm, StringRef Prefix);
void emit(AsmPrinter &Asm, MCSection *StrSection,
MCSection *OffsetSection = nullptr);
bool empty() const { return Pool.empty(); }
/// Get a reference to an entry in the string pool.
EntryRef getEntry(AsmPrinter &Asm, StringRef Str);
};
}
#endif