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 fragment.
20 MCFragment *MCSymbol::AbsolutePseudoFragment =
21 reinterpret_cast<MCFragment *>(4);
22
operator new(size_t s,const StringMapEntry<bool> * Name,MCContext & Ctx)23 void *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
setVariableValue(const MCExpr * Value)41 void 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
print(raw_ostream & OS,const MCAsmInfo * MAI) const52 void 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)
dump() const78 void MCSymbol::dump() const { dbgs() << *this; }
79 #endif
80