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"
17 using namespace llvm;
18
19 // Sentinel value for the absolute pseudo section.
20 MCSection *MCSymbol::AbsolutePseudoSection = reinterpret_cast<MCSection *>(1);
21
operator new(size_t s,const StringMapEntry<bool> * Name,MCContext & Ctx)22 void *MCSymbol::operator new(size_t s, const StringMapEntry<bool> *Name,
23 MCContext &Ctx) {
24 // We may need more space for a Name to account for alignment. So allocate
25 // space for the storage type and not the name pointer.
26 size_t Size = s + (Name ? sizeof(NameEntryStorageTy) : 0);
27
28 // For safety, ensure that the alignment of a pointer is enough for an
29 // MCSymbol. This also ensures we don't need padding between the name and
30 // symbol.
31 static_assert((unsigned)AlignOf<MCSymbol>::Alignment <=
32 AlignOf<NameEntryStorageTy>::Alignment,
33 "Bad alignment of MCSymbol");
34 void *Storage = Ctx.allocate(Size, alignOf<NameEntryStorageTy>());
35 NameEntryStorageTy *Start = static_cast<NameEntryStorageTy*>(Storage);
36 NameEntryStorageTy *End = Start + (Name ? 1 : 0);
37 return End;
38 }
39
setVariableValue(const MCExpr * Value)40 void MCSymbol::setVariableValue(const MCExpr *Value) {
41 assert(!IsUsed && "Cannot set a variable that has already been used.");
42 assert(Value && "Invalid variable value!");
43 assert((SymbolContents == SymContentsUnset ||
44 SymbolContents == SymContentsVariable) &&
45 "Cannot give common/offset symbol a variable value");
46 this->Value = Value;
47 SymbolContents = SymContentsVariable;
48 setUndefined();
49 }
50
print(raw_ostream & OS,const MCAsmInfo * MAI) const51 void MCSymbol::print(raw_ostream &OS, const MCAsmInfo *MAI) const {
52 // The name for this MCSymbol is required to be a valid target name. However,
53 // some targets support quoting names with funny characters. If the name
54 // contains a funny character, then print it quoted.
55 StringRef Name = getName();
56 if (!MAI || MAI->isValidUnquotedName(Name)) {
57 OS << Name;
58 return;
59 }
60
61 if (MAI && !MAI->supportsNameQuoting())
62 report_fatal_error("Symbol name with unsupported characters");
63
64 OS << '"';
65 for (char C : Name) {
66 if (C == '\n')
67 OS << "\\n";
68 else if (C == '"')
69 OS << "\\\"";
70 else
71 OS << C;
72 }
73 OS << '"';
74 }
75
76 #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
dump() const77 void MCSymbol::dump() const { dbgs() << *this; }
78 #endif
79