llvm-project/llvm/lib/VMCore/Mangler.cpp

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//===-- Mangler.cpp - Self-contained c/asm llvm name mangler --------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// Unified name mangler for CWriter and assembly backends.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Mangler.h"
#include "llvm/Function.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/StringMap.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
static char HexDigit(int V) {
return V < 10 ? V+'0' : V+'A'-10;
}
static std::string MangleLetter(unsigned char C) {
char Result[] = { '_', HexDigit(C >> 4), HexDigit(C & 15), '_', 0 };
return Result;
}
/// makeNameProper - We don't want identifier names non-C-identifier characters
/// in them, so mangle them as appropriate.
///
std::string Mangler::makeNameProper(const std::string &X,
ManglerPrefixTy PrefixTy) {
assert(!X.empty() && "Cannot mangle empty strings");
if (!UseQuotes) {
std::string Result;
// If X does not start with (char)1, add the prefix.
bool NeedPrefix = true;
std::string::const_iterator I = X.begin();
if (*I == 1) {
NeedPrefix = false;
++I; // Skip over the marker.
}
// Mangle the first letter specially, don't allow numbers unless the target
// explicitly allows them.
if (!SymbolsCanStartWithDigit && *I >= '0' && *I <= '9')
Result += MangleLetter(*I++);
for (std::string::const_iterator E = X.end(); I != E; ++I) {
if (!isCharAcceptable(*I))
Result += MangleLetter(*I);
else
Result += *I;
}
if (NeedPrefix) {
Result = Prefix + Result;
if (PrefixTy == Mangler::Private)
Result = PrivatePrefix + Result;
else if (PrefixTy == Mangler::LinkerPrivate)
Result = LinkerPrivatePrefix + Result;
}
return Result;
}
bool NeedPrefix = true;
bool NeedQuotes = false;
std::string Result;
std::string::const_iterator I = X.begin();
if (*I == 1) {
NeedPrefix = false;
++I; // Skip over the marker.
}
// If the first character is a number, we need quotes.
if (*I >= '0' && *I <= '9')
NeedQuotes = true;
// Do an initial scan of the string, checking to see if we need quotes or
// to escape a '"' or not.
if (!NeedQuotes)
for (std::string::const_iterator E = X.end(); I != E; ++I)
if (!isCharAcceptable(*I)) {
NeedQuotes = true;
break;
}
// In the common case, we don't need quotes. Handle this quickly.
if (!NeedQuotes) {
if (!NeedPrefix)
return X.substr(1); // Strip off the \001.
Result = Prefix + X;
if (PrefixTy == Mangler::Private)
Result = PrivatePrefix + Result;
else if (PrefixTy == Mangler::LinkerPrivate)
Result = LinkerPrivatePrefix + Result;
return Result;
}
if (NeedPrefix)
Result = X.substr(0, I-X.begin());
// Otherwise, construct the string the expensive way.
for (std::string::const_iterator E = X.end(); I != E; ++I) {
if (*I == '"')
Result += "_QQ_";
else if (*I == '\n')
Result += "_NL_";
else
Result += *I;
}
if (NeedPrefix) {
Result = Prefix + Result;
if (PrefixTy == Mangler::Private)
Result = PrivatePrefix + Result;
else if (PrefixTy == Mangler::LinkerPrivate)
Result = LinkerPrivatePrefix + Result;
}
Result = '"' + Result + '"';
return Result;
}
/// getMangledName - Returns the mangled name of V, an LLVM Value,
/// in the current module. If 'Suffix' is specified, the name ends with the
/// specified suffix. If 'ForcePrivate' is specified, the label is specified
/// to have a private label prefix.
///
std::string Mangler::getMangledName(const GlobalValue *GV, const char *Suffix,
bool ForcePrivate) {
assert((!isa<Function>(GV) || !cast<Function>(GV)->isIntrinsic()) &&
"Intrinsic functions cannot be mangled by Mangler");
ManglerPrefixTy PrefixTy =
(GV->hasPrivateLinkage() || ForcePrivate) ? Mangler::Private :
GV->hasLinkerPrivateLinkage() ? Mangler::LinkerPrivate : Mangler::Default;
if (GV->hasName())
return makeNameProper(GV->getNameStr() + Suffix, PrefixTy);
// Get the ID for the global, assigning a new one if we haven't got one
// already.
unsigned &ID = AnonGlobalIDs[GV];
if (ID == 0) ID = NextAnonGlobalID++;
// Must mangle the global into a unique ID.
return makeNameProper("__unnamed_" + utostr(ID) + Suffix, PrefixTy);
}
/// getNameWithPrefix - Fill OutName with the name of the appropriate prefix
/// and the specified global variable's name. If the global variable doesn't
/// have a name, this fills in a unique name for the global.
void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
const GlobalValue *GV,
bool isImplicitlyPrivate) {
// If the global is anonymous or not led with \1, then add the appropriate
// prefix.
if (!GV->hasName() || GV->getName()[0] != '\1') {
if (GV->hasPrivateLinkage() || isImplicitlyPrivate)
OutName.append(PrivatePrefix, PrivatePrefix+strlen(PrivatePrefix));
else if (GV->hasLinkerPrivateLinkage())
OutName.append(LinkerPrivatePrefix,
LinkerPrivatePrefix+strlen(LinkerPrivatePrefix));;
OutName.append(Prefix, Prefix+strlen(Prefix));
}
// If the global has a name, just append it now.
if (GV->hasName()) {
StringRef Name = GV->getName();
// Strip off the prefix marker if present.
if (Name[0] != '\1')
OutName.append(Name.begin(), Name.end());
else
OutName.append(Name.begin()+1, Name.end());
return;
}
// If the global variable doesn't have a name, return a unique name for the
// global based on a numbering.
// Get the ID for the global, assigning a new one if we haven't got one
// already.
unsigned &ID = AnonGlobalIDs[GV];
if (ID == 0) ID = NextAnonGlobalID++;
// Must mangle the global into a unique ID.
raw_svector_ostream(OutName) << "__unnamed_" << ID;
}
Mangler::Mangler(Module &M, const char *prefix, const char *privatePrefix,
const char *linkerPrivatePrefix)
: Prefix(prefix), PrivatePrefix(privatePrefix),
LinkerPrivatePrefix(linkerPrivatePrefix), UseQuotes(false),
NextAnonGlobalID(1) {
std::fill(AcceptableChars, array_endof(AcceptableChars), 0);
// Letters and numbers are acceptable.
for (unsigned char X = 'a'; X <= 'z'; ++X)
markCharAcceptable(X);
for (unsigned char X = 'A'; X <= 'Z'; ++X)
markCharAcceptable(X);
for (unsigned char X = '0'; X <= '9'; ++X)
markCharAcceptable(X);
// These chars are acceptable.
markCharAcceptable('_');
markCharAcceptable('$');
markCharAcceptable('.');
markCharAcceptable('@');
}