llvm/lib/VMCore/Mangler.cpp
2003-08-24 21:08:38 +00:00

95 lines
3.3 KiB
C++

//===-- Mangler.cpp - Self-contained c/asm llvm name mangler --------------===//
//
// Unified name mangler for CWriter and assembly backends.
//
//===----------------------------------------------------------------------===//
#include "llvm/Support/Mangler.h"
#include "llvm/Module.h"
#include "llvm/Type.h"
#include "Support/StringExtras.h"
static char HexDigit(int V) {
return V < 10 ? V+'0' : V+'A'-10;
}
static std::string MangleLetter(unsigned char C) {
return std::string("_")+HexDigit(C >> 4) + HexDigit(C & 15) + "_";
}
/// 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) {
std::string Result;
// Mangle the first letter specially, don't allow numbers...
if ((X[0] < 'a' || X[0] > 'z') && (X[0] < 'A' || X[0] > 'Z') && X[0] != '_')
Result += MangleLetter(X[0]);
else
Result += X[0];
for (std::string::const_iterator I = X.begin()+1, E = X.end(); I != E; ++I)
if ((*I < 'a' || *I > 'z') && (*I < 'A' || *I > 'Z') &&
(*I < '0' || *I > '9') && *I != '_')
Result += MangleLetter(*I);
else
Result += *I;
return Result;
}
std::string Mangler::getValueName(const Value *V) {
// Check to see whether we've already named V.
ValueMap::iterator VI = Memo.find(V);
if (VI != Memo.end()) {
return VI->second; // Return the old name for V.
}
std::string name;
if (V->hasName()) { // Print out the label if it exists...
// Name mangling occurs as follows:
// - If V is not a global, mangling always occurs.
// - Otherwise, mangling occurs when any of the following are true:
// 1) V has internal linkage
// 2) V's name would collide if it is not mangled.
//
const GlobalValue* gv = dyn_cast<GlobalValue>(V);
if (gv && !gv->hasInternalLinkage() && !MangledGlobals.count(gv)) {
name = makeNameProper(gv->getName());
if (AddUnderscorePrefix) name = "_" + name;
} else {
// Non-global, or global with internal linkage / colliding name
// -> mangle.
name = "l" + utostr(V->getType()->getUniqueID()) + "_" +
makeNameProper(V->getName());
}
} else {
name = "ltmp_" + utostr(Count++) + "_"
+ utostr(V->getType()->getUniqueID());
}
Memo[V] = name;
return name;
}
Mangler::Mangler(Module &m, bool addUnderscorePrefix)
: M(m), AddUnderscorePrefix(addUnderscorePrefix) {
// Calculate which global values have names that will collide when we throw
// away type information.
std::set<std::string> FoundNames;
for (Module::iterator I = M.begin(), E = M.end(); I != E; ++I)
if (I->hasName()) // If the global has a name...
if (FoundNames.count(I->getName())) // And the name is already used
MangledGlobals.insert(I); // Mangle the name
else
FoundNames.insert(I->getName()); // Otherwise, keep track of name
for (Module::giterator I = M.gbegin(), E = M.gend(); I != E; ++I)
if (I->hasName()) // If the global has a name...
if (FoundNames.count(I->getName())) // And the name is already used
MangledGlobals.insert(I); // Mangle the name
else
FoundNames.insert(I->getName()); // Otherwise, keep track of name
}