lib/MC/MCSymbol.cpp

   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/MCExpr.h"
  12 #include "llvm/Support/Debug.h"
  13 #include "llvm/Support/raw_ostream.h"
  14 using namespace llvm;
  15
  16 // Sentinel value for the absolute pseudo section.
  17 const MCSection *MCSymbol::AbsolutePseudoSection =
  18   reinterpret_cast<const MCSection *>(1);
  19
  20 static bool isAcceptableChar(char C) {
  21   if ((C < 'a' || C > 'z') &&
  22       (C < 'A' || C > 'Z') &&
  23       (C < '0' || C > '9') &&
  24       C != '_' && C != '$' && C != '.' && C != '@')
  25     return false;
  26   return true;
  27 }
  28
  29 /// NameNeedsQuoting - Return true if the identifier \arg Str needs quotes to be
  30 /// syntactically correct.
  31 static bool NameNeedsQuoting(StringRef Str) {
  32   assert(!Str.empty() && "Cannot create an empty MCSymbol");
  33
  34   // If any of the characters in the string is an unacceptable character, force
  35   // quotes.
  36   for (unsigned i = 0, e = Str.size(); i != e; ++i)
  37     if (!isAcceptableChar(Str[i]))
  38       return true;
  39   return false;
  40 }
  41
  42 void MCSymbol::setVariableValue(const MCExpr *Value) {
  43   assert(Value && "Invalid variable value!");
  44   assert((isUndefined() || (isAbsolute() && isa<MCConstantExpr>(Value))) &&
  45          "Invalid redefinition!");
  46   this->Value = Value;
  47
  48   // Mark the variable as absolute as appropriate.
  49   if (isa<MCConstantExpr>(Value))
  50     setAbsolute();
  51 }
  52
  53 void MCSymbol::print(raw_ostream &OS) const {
  54   // The name for this MCSymbol is required to be a valid target name.  However,
  55   // some targets support quoting names with funny characters.  If the name
  56   // contains a funny character, then print it quoted.
  57   if (!NameNeedsQuoting(getName())) {
  58     OS << getName();
  59     return;
  60   }
  61
  62   OS << '"' << getName() << '"';
  63 }
  64
  65 void MCSymbol::dump() const {
  66   print(dbgs());
  67 }