mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2025-01-17 06:33:21 +00:00
484a6eb9cc
It can now disassemble code in situations where the effective load address is different than the load address declared in the object file. This happens for PIC, hence "dynamic". git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@188884 91177308-0d34-0410-b5e6-96231b3b80d8
288 lines
8.7 KiB
C++
288 lines
8.7 KiB
C++
//===- lib/MC/MCObjectDisassembler.cpp ------------------------------------===//
|
|
//
|
|
// The LLVM Compiler Infrastructure
|
|
//
|
|
// This file is distributed under the University of Illinois Open Source
|
|
// License. See LICENSE.TXT for details.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "llvm/MC/MCObjectDisassembler.h"
|
|
#include "llvm/ADT/STLExtras.h"
|
|
#include "llvm/ADT/SetVector.h"
|
|
#include "llvm/ADT/StringExtras.h"
|
|
#include "llvm/ADT/StringRef.h"
|
|
#include "llvm/ADT/Twine.h"
|
|
#include "llvm/MC/MCAtom.h"
|
|
#include "llvm/MC/MCDisassembler.h"
|
|
#include "llvm/MC/MCFunction.h"
|
|
#include "llvm/MC/MCInstrAnalysis.h"
|
|
#include "llvm/MC/MCModule.h"
|
|
#include "llvm/Object/ObjectFile.h"
|
|
#include "llvm/Support/MemoryObject.h"
|
|
#include "llvm/Support/StringRefMemoryObject.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
#include <map>
|
|
#include <set>
|
|
|
|
using namespace llvm;
|
|
using namespace object;
|
|
|
|
MCObjectDisassembler::MCObjectDisassembler(const ObjectFile &Obj,
|
|
const MCDisassembler &Dis,
|
|
const MCInstrAnalysis &MIA)
|
|
: Obj(Obj), Dis(Dis), MIA(MIA) {}
|
|
|
|
uint64_t MCObjectDisassembler::getEntrypoint() {
|
|
error_code ec;
|
|
for (symbol_iterator SI = Obj.begin_symbols(), SE = Obj.end_symbols();
|
|
SI != SE; SI.increment(ec)) {
|
|
if (ec)
|
|
break;
|
|
StringRef Name;
|
|
SI->getName(Name);
|
|
if (Name == "main" || Name == "_main") {
|
|
uint64_t Entrypoint;
|
|
SI->getAddress(Entrypoint);
|
|
return getEffectiveLoadAddr(Entrypoint);
|
|
}
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
ArrayRef<uint64_t> MCObjectDisassembler::getStaticInitFunctions() {
|
|
return ArrayRef<uint64_t>();
|
|
}
|
|
|
|
ArrayRef<uint64_t> MCObjectDisassembler::getStaticExitFunctions() {
|
|
return ArrayRef<uint64_t>();
|
|
}
|
|
|
|
uint64_t MCObjectDisassembler::getEffectiveLoadAddr(uint64_t Addr) {
|
|
return Addr;
|
|
}
|
|
|
|
uint64_t MCObjectDisassembler::getOriginalLoadAddr(uint64_t Addr) {
|
|
return Addr;
|
|
}
|
|
|
|
MCModule *MCObjectDisassembler::buildEmptyModule() {
|
|
MCModule *Module = new MCModule;
|
|
Module->Entrypoint = getEntrypoint();
|
|
return Module;
|
|
}
|
|
|
|
MCModule *MCObjectDisassembler::buildModule(bool withCFG) {
|
|
MCModule *Module = buildEmptyModule();
|
|
|
|
buildSectionAtoms(Module);
|
|
if (withCFG)
|
|
buildCFG(Module);
|
|
return Module;
|
|
}
|
|
|
|
void MCObjectDisassembler::buildSectionAtoms(MCModule *Module) {
|
|
error_code ec;
|
|
for (section_iterator SI = Obj.begin_sections(),
|
|
SE = Obj.end_sections();
|
|
SI != SE;
|
|
SI.increment(ec)) {
|
|
if (ec) break;
|
|
|
|
bool isText; SI->isText(isText);
|
|
bool isData; SI->isData(isData);
|
|
if (!isData && !isText)
|
|
continue;
|
|
|
|
uint64_t StartAddr; SI->getAddress(StartAddr);
|
|
uint64_t SecSize; SI->getSize(SecSize);
|
|
if (StartAddr == UnknownAddressOrSize || SecSize == UnknownAddressOrSize)
|
|
continue;
|
|
StartAddr = getEffectiveLoadAddr(StartAddr);
|
|
|
|
StringRef Contents; SI->getContents(Contents);
|
|
StringRefMemoryObject memoryObject(Contents, StartAddr);
|
|
|
|
// We don't care about things like non-file-backed sections yet.
|
|
if (Contents.size() != SecSize || !SecSize)
|
|
continue;
|
|
uint64_t EndAddr = StartAddr + SecSize - 1;
|
|
|
|
StringRef SecName; SI->getName(SecName);
|
|
|
|
if (isText) {
|
|
MCTextAtom *Text = 0;
|
|
MCDataAtom *InvalidData = 0;
|
|
|
|
uint64_t InstSize;
|
|
for (uint64_t Index = 0; Index < SecSize; Index += InstSize) {
|
|
const uint64_t CurAddr = StartAddr + Index;
|
|
MCInst Inst;
|
|
if (Dis.getInstruction(Inst, InstSize, memoryObject, CurAddr, nulls(),
|
|
nulls())) {
|
|
if (!Text) {
|
|
Text = Module->createTextAtom(CurAddr, CurAddr);
|
|
Text->setName(SecName);
|
|
}
|
|
Text->addInst(Inst, InstSize);
|
|
InvalidData = 0;
|
|
} else {
|
|
if (!InvalidData) {
|
|
Text = 0;
|
|
InvalidData = Module->createDataAtom(CurAddr, EndAddr);
|
|
}
|
|
InvalidData->addData(Contents[Index]);
|
|
}
|
|
}
|
|
} else {
|
|
MCDataAtom *Data = Module->createDataAtom(StartAddr, EndAddr);
|
|
Data->setName(SecName);
|
|
for (uint64_t Index = 0; Index < SecSize; ++Index)
|
|
Data->addData(Contents[Index]);
|
|
}
|
|
}
|
|
}
|
|
|
|
namespace {
|
|
struct BBInfo;
|
|
typedef std::set<BBInfo*> BBInfoSetTy;
|
|
|
|
struct BBInfo {
|
|
MCTextAtom *Atom;
|
|
MCBasicBlock *BB;
|
|
BBInfoSetTy Succs;
|
|
BBInfoSetTy Preds;
|
|
|
|
BBInfo() : Atom(0), BB(0) {}
|
|
|
|
void addSucc(BBInfo &Succ) {
|
|
Succs.insert(&Succ);
|
|
Succ.Preds.insert(this);
|
|
}
|
|
};
|
|
}
|
|
|
|
void MCObjectDisassembler::buildCFG(MCModule *Module) {
|
|
typedef std::map<uint64_t, BBInfo> BBInfoByAddrTy;
|
|
BBInfoByAddrTy BBInfos;
|
|
typedef std::set<uint64_t> AddressSetTy;
|
|
AddressSetTy Splits;
|
|
AddressSetTy Calls;
|
|
|
|
error_code ec;
|
|
for (symbol_iterator SI = Obj.begin_symbols(), SE = Obj.end_symbols();
|
|
SI != SE; SI.increment(ec)) {
|
|
if (ec)
|
|
break;
|
|
SymbolRef::Type SymType;
|
|
SI->getType(SymType);
|
|
if (SymType == SymbolRef::ST_Function) {
|
|
uint64_t SymAddr;
|
|
SI->getAddress(SymAddr);
|
|
SymAddr = getEffectiveLoadAddr(SymAddr);
|
|
Calls.insert(SymAddr);
|
|
Splits.insert(SymAddr);
|
|
}
|
|
}
|
|
|
|
assert(Module->func_begin() == Module->func_end()
|
|
&& "Module already has a CFG!");
|
|
|
|
// First, determine the basic block boundaries and call targets.
|
|
for (MCModule::atom_iterator AI = Module->atom_begin(),
|
|
AE = Module->atom_end();
|
|
AI != AE; ++AI) {
|
|
MCTextAtom *TA = dyn_cast<MCTextAtom>(*AI);
|
|
if (!TA) continue;
|
|
Calls.insert(TA->getBeginAddr());
|
|
BBInfos[TA->getBeginAddr()].Atom = TA;
|
|
for (MCTextAtom::const_iterator II = TA->begin(), IE = TA->end();
|
|
II != IE; ++II) {
|
|
if (MIA.isTerminator(II->Inst))
|
|
Splits.insert(II->Address + II->Size);
|
|
uint64_t Target;
|
|
if (MIA.evaluateBranch(II->Inst, II->Address, II->Size, Target)) {
|
|
if (MIA.isCall(II->Inst))
|
|
Calls.insert(Target);
|
|
Splits.insert(Target);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Split text atoms into basic block atoms.
|
|
for (AddressSetTy::const_iterator SI = Splits.begin(), SE = Splits.end();
|
|
SI != SE; ++SI) {
|
|
MCAtom *A = Module->findAtomContaining(*SI);
|
|
if (!A) continue;
|
|
MCTextAtom *TA = cast<MCTextAtom>(A);
|
|
if (TA->getBeginAddr() == *SI)
|
|
continue;
|
|
MCTextAtom *NewAtom = TA->split(*SI);
|
|
BBInfos[NewAtom->getBeginAddr()].Atom = NewAtom;
|
|
StringRef BBName = TA->getName();
|
|
BBName = BBName.substr(0, BBName.find_last_of(':'));
|
|
NewAtom->setName((BBName + ":" + utohexstr(*SI)).str());
|
|
}
|
|
|
|
// Compute succs/preds.
|
|
for (MCModule::atom_iterator AI = Module->atom_begin(),
|
|
AE = Module->atom_end();
|
|
AI != AE; ++AI) {
|
|
MCTextAtom *TA = dyn_cast<MCTextAtom>(*AI);
|
|
if (!TA) continue;
|
|
BBInfo &CurBB = BBInfos[TA->getBeginAddr()];
|
|
const MCDecodedInst &LI = TA->back();
|
|
if (MIA.isBranch(LI.Inst)) {
|
|
uint64_t Target;
|
|
if (MIA.evaluateBranch(LI.Inst, LI.Address, LI.Size, Target))
|
|
CurBB.addSucc(BBInfos[Target]);
|
|
if (MIA.isConditionalBranch(LI.Inst))
|
|
CurBB.addSucc(BBInfos[LI.Address + LI.Size]);
|
|
} else if (!MIA.isTerminator(LI.Inst))
|
|
CurBB.addSucc(BBInfos[LI.Address + LI.Size]);
|
|
}
|
|
|
|
|
|
// Create functions and basic blocks.
|
|
for (AddressSetTy::const_iterator CI = Calls.begin(), CE = Calls.end();
|
|
CI != CE; ++CI) {
|
|
BBInfo &BBI = BBInfos[*CI];
|
|
if (!BBI.Atom) continue;
|
|
|
|
MCFunction &MCFN = *Module->createFunction(BBI.Atom->getName());
|
|
|
|
// Create MCBBs.
|
|
SmallSetVector<BBInfo*, 16> Worklist;
|
|
Worklist.insert(&BBI);
|
|
for (size_t wi = 0; wi < Worklist.size(); ++wi) {
|
|
BBInfo *BBI = Worklist[wi];
|
|
if (!BBI->Atom)
|
|
continue;
|
|
BBI->BB = &MCFN.createBlock(*BBI->Atom);
|
|
// Add all predecessors and successors to the worklist.
|
|
for (BBInfoSetTy::iterator SI = BBI->Succs.begin(), SE = BBI->Succs.end();
|
|
SI != SE; ++SI)
|
|
Worklist.insert(*SI);
|
|
for (BBInfoSetTy::iterator PI = BBI->Preds.begin(), PE = BBI->Preds.end();
|
|
PI != PE; ++PI)
|
|
Worklist.insert(*PI);
|
|
}
|
|
|
|
// Set preds/succs.
|
|
for (size_t wi = 0; wi < Worklist.size(); ++wi) {
|
|
BBInfo *BBI = Worklist[wi];
|
|
MCBasicBlock *MCBB = BBI->BB;
|
|
if (!MCBB)
|
|
continue;
|
|
for (BBInfoSetTy::iterator SI = BBI->Succs.begin(), SE = BBI->Succs.end();
|
|
SI != SE; ++SI)
|
|
if ((*SI)->BB)
|
|
MCBB->addSuccessor((*SI)->BB);
|
|
for (BBInfoSetTy::iterator PI = BBI->Preds.begin(), PE = BBI->Preds.end();
|
|
PI != PE; ++PI)
|
|
if ((*PI)->BB)
|
|
MCBB->addPredecessor((*PI)->BB);
|
|
}
|
|
}
|
|
}
|