1//===- lib/MC/MCSymbol.cpp - MCSymbol implementation ----------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9
10#include "llvm/MC/MCSymbol.h"
11#include "llvm/MC/MCAsmInfo.h"
12#include "llvm/MC/MCContext.h"
13#include "llvm/MC/MCExpr.h"
14#include "llvm/Support/Debug.h"
15#include "llvm/Support/ErrorHandling.h"
16#include "llvm/Support/raw_ostream.h"
17using namespace llvm;
18
19// Sentinel value for the absolute pseudo fragment.
20MCFragment *MCSymbol::AbsolutePseudoFragment =
21    reinterpret_cast<MCFragment *>(4);
22
23void *MCSymbol::operator new(size_t s, const StringMapEntry<bool> *Name,
24                             MCContext &Ctx) {
25  // We may need more space for a Name to account for alignment.  So allocate
26  // space for the storage type and not the name pointer.
27  size_t Size = s + (Name ? sizeof(NameEntryStorageTy) : 0);
28
29  // For safety, ensure that the alignment of a pointer is enough for an
30  // MCSymbol.  This also ensures we don't need padding between the name and
31  // symbol.
32  static_assert((unsigned)AlignOf<MCSymbol>::Alignment <=
33                AlignOf<NameEntryStorageTy>::Alignment,
34                "Bad alignment of MCSymbol");
35  void *Storage = Ctx.allocate(Size, alignOf<NameEntryStorageTy>());
36  NameEntryStorageTy *Start = static_cast<NameEntryStorageTy*>(Storage);
37  NameEntryStorageTy *End = Start + (Name ? 1 : 0);
38  return End;
39}
40
41void MCSymbol::setVariableValue(const MCExpr *Value) {
42  assert(!IsUsed && "Cannot set a variable that has already been used.");
43  assert(Value && "Invalid variable value!");
44  assert((SymbolContents == SymContentsUnset ||
45          SymbolContents == SymContentsVariable) &&
46         "Cannot give common/offset symbol a variable value");
47  this->Value = Value;
48  SymbolContents = SymContentsVariable;
49  setUndefined();
50}
51
52void MCSymbol::print(raw_ostream &OS, const MCAsmInfo *MAI) const {
53  // The name for this MCSymbol is required to be a valid target name.  However,
54  // some targets support quoting names with funny characters.  If the name
55  // contains a funny character, then print it quoted.
56  StringRef Name = getName();
57  if (!MAI || MAI->isValidUnquotedName(Name)) {
58    OS << Name;
59    return;
60  }
61
62  if (MAI && !MAI->supportsNameQuoting())
63    report_fatal_error("Symbol name with unsupported characters");
64
65  OS << '"';
66  for (char C : Name) {
67    if (C == '\n')
68      OS << "\\n";
69    else if (C == '"')
70      OS << "\\\"";
71    else
72      OS << C;
73  }
74  OS << '"';
75}
76
77#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
78void MCSymbol::dump() const { dbgs() << *this; }
79#endif
80