llvm-6502/lib/IR/Mangler.cpp
Chandler Carruth 6b71233fb1 Remove vestigal bits of MC from the mangler. It no longer uses this, and
having the include could cause weird layering problems between the IR
and MC libraries.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@198796 91177308-0d34-0410-b5e6-96231b3b80d8
2014-01-08 21:59:22 +00:00

129 lines
4.8 KiB
C++

//===-- 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 assembly backends.
//
//===----------------------------------------------------------------------===//
#include "llvm/IR/Mangler.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/ADT/Twine.h"
#include "llvm/IR/DataLayout.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
/// getNameWithPrefix - Fill OutName with the name of the appropriate prefix
/// and the specified name as the global variable name. GVName must not be
/// empty.
void Mangler::getNameWithPrefix(SmallVectorImpl<char> &OutName,
const Twine &GVName, ManglerPrefixTy PrefixTy) {
SmallString<256> TmpData;
StringRef Name = GVName.toStringRef(TmpData);
assert(!Name.empty() && "getNameWithPrefix requires non-empty name");
// If the global name is not led with \1, add the appropriate prefixes.
if (Name[0] == '\1') {
Name = Name.substr(1);
} else {
if (PrefixTy == Mangler::Private) {
const char *Prefix = DL->getPrivateGlobalPrefix();
OutName.append(Prefix, Prefix+strlen(Prefix));
} else if (PrefixTy == Mangler::LinkerPrivate) {
const char *Prefix = DL->getLinkerPrivateGlobalPrefix();
OutName.append(Prefix, Prefix+strlen(Prefix));
}
char Prefix = DL->getGlobalPrefix();
if (Prefix != '\0')
OutName.push_back(Prefix);
}
// If this is a simple string that doesn't need escaping, just append it.
OutName.append(Name.begin(), Name.end());
}
/// AddFastCallStdCallSuffix - Microsoft fastcall and stdcall functions require
/// a suffix on their name indicating the number of words of arguments they
/// take.
static void AddFastCallStdCallSuffix(SmallVectorImpl<char> &OutName,
const Function *F, const DataLayout &TD) {
// Calculate arguments size total.
unsigned ArgWords = 0;
for (Function::const_arg_iterator AI = F->arg_begin(), AE = F->arg_end();
AI != AE; ++AI) {
Type *Ty = AI->getType();
// 'Dereference' type in case of byval parameter attribute
if (AI->hasByValAttr())
Ty = cast<PointerType>(Ty)->getElementType();
// Size should be aligned to DWORD boundary
ArgWords += ((TD.getTypeAllocSize(Ty) + 3)/4)*4;
}
raw_svector_ostream(OutName) << '@' << ArgWords;
}
/// 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) {
ManglerPrefixTy PrefixTy = Mangler::Default;
if (GV->hasPrivateLinkage())
PrefixTy = Mangler::Private;
else if (GV->hasLinkerPrivateLinkage() || GV->hasLinkerPrivateWeakLinkage())
PrefixTy = Mangler::LinkerPrivate;
// If this global has a name, handle it simply.
if (GV->hasName()) {
StringRef Name = GV->getName();
getNameWithPrefix(OutName, Name, PrefixTy);
// No need to do anything else if the global has the special "do not mangle"
// flag in the name.
if (Name[0] == 1)
return;
} else {
// 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.
getNameWithPrefix(OutName, "__unnamed_" + Twine(ID), PrefixTy);
}
// If we are supposed to add a microsoft-style suffix for stdcall/fastcall,
// add it.
if (DL->hasMicrosoftFastStdCallMangling()) {
if (const Function *F = dyn_cast<Function>(GV)) {
CallingConv::ID CC = F->getCallingConv();
// fastcall functions need to start with @.
// FIXME: This logic seems unlikely to be right.
if (CC == CallingConv::X86_FastCall) {
if (OutName[0] == '_')
OutName[0] = '@';
else
OutName.insert(OutName.begin(), '@');
}
// fastcall and stdcall functions usually need @42 at the end to specify
// the argument info.
FunctionType *FT = F->getFunctionType();
if ((CC == CallingConv::X86_FastCall || CC == CallingConv::X86_StdCall) &&
// "Pure" variadic functions do not receive @0 suffix.
(!FT->isVarArg() || FT->getNumParams() == 0 ||
(FT->getNumParams() == 1 && F->hasStructRetAttr())))
AddFastCallStdCallSuffix(OutName, F, *DL);
}
}
}