| //===- lib/MC/MCSymbol.cpp - MCSymbol implementation ----------------------===// |
| // |
| // The LLVM Compiler Infrastructure |
| // |
| // This file is distributed under the University of Illinois Open Source |
| // License. See LICENSE.TXT for details. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "llvm/MC/MCSymbol.h" |
| #include "llvm/MC/MCAsmInfo.h" |
| #include "llvm/Support/raw_ostream.h" |
| using namespace llvm; |
| |
| // Sentinel value for the absolute pseudo section. |
| const MCSection *MCSymbol::AbsolutePseudoSection = |
| reinterpret_cast<const MCSection *>(1); |
| |
| static bool isAcceptableChar(char C) { |
| if ((C < 'a' || C > 'z') && |
| (C < 'A' || C > 'Z') && |
| (C < '0' || C > '9') && |
| C != '_' && C != '$' && C != '.' && C != '@') |
| return false; |
| return true; |
| } |
| |
| static char HexDigit(int V) { |
| return V < 10 ? V+'0' : V+'A'-10; |
| } |
| |
| static void MangleLetter(raw_ostream &OS, unsigned char C) { |
| OS << '_' << HexDigit(C >> 4) << HexDigit(C & 15) << '_'; |
| } |
| |
| /// NameNeedsEscaping - Return true if the identifier \arg Str needs quotes |
| /// for this assembler. |
| static bool NameNeedsEscaping(StringRef Str, const MCAsmInfo &MAI) { |
| assert(!Str.empty() && "Cannot create an empty MCSymbol"); |
| |
| // If the first character is a number and the target does not allow this, we |
| // need quotes. |
| if (!MAI.doesAllowNameToStartWithDigit() && Str[0] >= '0' && Str[0] <= '9') |
| return true; |
| |
| // If any of the characters in the string is an unacceptable character, force |
| // quotes. |
| for (unsigned i = 0, e = Str.size(); i != e; ++i) |
| if (!isAcceptableChar(Str[i])) |
| return true; |
| return false; |
| } |
| |
| static void PrintMangledName(raw_ostream &OS, StringRef Str, |
| const MCAsmInfo &MAI) { |
| // The first character is not allowed to be a number unless the target |
| // explicitly allows it. |
| if (!MAI.doesAllowNameToStartWithDigit() && Str[0] >= '0' && Str[0] <= '9') { |
| MangleLetter(OS, Str[0]); |
| Str = Str.substr(1); |
| } |
| |
| for (unsigned i = 0, e = Str.size(); i != e; ++i) { |
| if (!isAcceptableChar(Str[i])) |
| MangleLetter(OS, Str[i]); |
| else |
| OS << Str[i]; |
| } |
| } |
| |
| /// PrintMangledQuotedName - On systems that support quoted symbols, we still |
| /// have to escape some (obscure) characters like " and \n which would break the |
| /// assembler's lexing. |
| static void PrintMangledQuotedName(raw_ostream &OS, StringRef Str) { |
| OS << '"'; |
| |
| for (unsigned i = 0, e = Str.size(); i != e; ++i) { |
| if (Str[i] == '"') |
| OS << "_QQ_"; |
| else if (Str[i] == '\n') |
| OS << "_NL_"; |
| else |
| OS << Str[i]; |
| } |
| OS << '"'; |
| } |
| |
| |
| void MCSymbol::print(raw_ostream &OS, const MCAsmInfo *MAI) const { |
| if (MAI == 0 || !NameNeedsEscaping(getName(), *MAI)) { |
| OS << getName(); |
| return; |
| } |
| |
| // On systems that do not allow quoted names, print with mangling. |
| if (!MAI->doesAllowQuotesInName()) |
| return PrintMangledName(OS, getName(), *MAI); |
| |
| // If the string contains a double quote or newline, we still have to mangle |
| // it. |
| if (getName().find('"') != std::string::npos || |
| getName().find('\n') != std::string::npos) |
| return PrintMangledQuotedName(OS, getName()); |
| |
| OS << '"' << getName() << '"'; |
| } |
| |
| void MCSymbol::dump() const { |
| print(errs(), 0); |
| } |