ghidra/Ghidra/Features/Decompiler/src/decompile/cpp/sleighbase.cc
2024-06-11 17:41:06 +00:00

369 lines
12 KiB
C++

/* ###
* IP: GHIDRA
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "sleighbase.hh"
namespace ghidra {
const uint4 SleighBase::MAX_UNIQUE_SIZE = 128;
int4 SourceFileIndexer::index(const string filename){
auto it = fileToIndex.find(filename);
if (fileToIndex.end() != it){
return it->second;
}
fileToIndex[filename] = leastUnusedIndex;
indexToFile[leastUnusedIndex] = filename;
return leastUnusedIndex++;
}
int4 SourceFileIndexer::getIndex(string filename){
return fileToIndex[filename];
}
string SourceFileIndexer::getFilename(int4 index){
return indexToFile[index];
}
void SourceFileIndexer::decode(Decoder &decoder)
{
uint4 el = decoder.openElement(sla::ELEM_SOURCEFILES);
while(decoder.peekElement() == sla::ELEM_SOURCEFILE) {
int4 subel = decoder.openElement();
string filename = decoder.readString(sla::ATTRIB_NAME);
int4 index = decoder.readSignedInteger(sla::ATTRIB_INDEX);
decoder.closeElement(subel);
fileToIndex[filename] = index;
indexToFile[index] = filename;
}
decoder.closeElement(el);
}
void SourceFileIndexer::encode(Encoder &encoder) const
{
encoder.openElement(sla::ELEM_SOURCEFILES);
for (int4 i = 0; i < leastUnusedIndex; ++i){
encoder.openElement(sla::ELEM_SOURCEFILE);
encoder.writeString(sla::ATTRIB_NAME, indexToFile.at(i));
encoder.writeSignedInteger(sla::ATTRIB_INDEX, i);
encoder.closeElement(sla::ELEM_SOURCEFILE);
}
encoder.closeElement(sla::ELEM_SOURCEFILES);
}
SleighBase::SleighBase(void)
{
root = (SubtableSymbol *)0;
maxdelayslotbytes = 0;
unique_allocatemask = 0;
numSections = 0;
}
/// Assuming the symbol table is populated, iterate through the table collecting
/// registers (for the map), user-op names, and context fields.
void SleighBase::buildXrefs(vector<string> &errorPairs)
{
SymbolScope *glb = symtab.getGlobalScope();
SymbolTree::const_iterator iter;
SleighSymbol *sym;
ostringstream s;
for(iter=glb->begin();iter!=glb->end();++iter) {
sym = *iter;
if (sym->getType() == SleighSymbol::varnode_symbol) {
pair<VarnodeData,string> ins(((VarnodeSymbol *)sym)->getFixedVarnode(),sym->getName());
pair<map<VarnodeData,string>::iterator,bool> res = varnode_xref.insert(ins);
if (!res.second) {
errorPairs.push_back(sym->getName());
errorPairs.push_back((*(res.first)).second);
}
}
else if (sym->getType() == SleighSymbol::userop_symbol) {
int4 index = ((UserOpSymbol *)sym)->getIndex();
while(userop.size() <= index)
userop.push_back("");
userop[index] = sym->getName();
}
else if (sym->getType() == SleighSymbol::context_symbol) {
ContextSymbol *csym = (ContextSymbol *)sym;
ContextField *field = (ContextField *)csym->getPatternValue();
int4 startbit = field->getStartBit();
int4 endbit = field->getEndBit();
registerContext(csym->getName(),startbit,endbit);
}
}
}
/// If \b this SleighBase is being reused with a new program, the context
/// variables need to be registered with the new program's database
void SleighBase::reregisterContext(void)
{
SymbolScope *glb = symtab.getGlobalScope();
SymbolTree::const_iterator iter;
SleighSymbol *sym;
for(iter=glb->begin();iter!=glb->end();++iter) {
sym = *iter;
if (sym->getType() == SleighSymbol::context_symbol) {
ContextSymbol *csym = (ContextSymbol *)sym;
ContextField *field = (ContextField *)csym->getPatternValue();
int4 startbit = field->getStartBit();
int4 endbit = field->getEndBit();
registerContext(csym->getName(),startbit,endbit);
}
}
}
const VarnodeData &SleighBase::getRegister(const string &nm) const
{
VarnodeSymbol *sym = (VarnodeSymbol *)findSymbol(nm);
if (sym == (VarnodeSymbol *)0)
throw SleighError("Unknown register name: "+nm);
if (sym->getType() != SleighSymbol::varnode_symbol)
throw SleighError("Symbol is not a register: "+nm);
return sym->getFixedVarnode();
}
string SleighBase::getRegisterName(AddrSpace *base,uintb off,int4 size) const
{
VarnodeData sym;
sym.space = base;
sym.offset = off;
sym.size = size;
map<VarnodeData,string>::const_iterator iter = varnode_xref.upper_bound(sym); // First point greater than offset
if (iter == varnode_xref.begin()) return "";
iter--;
const VarnodeData &point((*iter).first);
if (point.space != base) return "";
uintb offbase = point.offset;
if (point.offset+point.size >= off+size)
return (*iter).second;
while(iter != varnode_xref.begin()) {
--iter;
const VarnodeData &point((*iter).first);
if ((point.space != base)||(point.offset != offbase)) return "";
if (point.offset+point.size >= off+size)
return (*iter).second;
}
return "";
}
void SleighBase::getAllRegisters(map<VarnodeData,string> &reglist) const
{
reglist = varnode_xref;
}
void SleighBase::getUserOpNames(vector<string> &res) const
{
res = userop; // Return list of all language defined user ops (with index)
}
/// Write a tag fully describing the details of the space.
/// \param encoder is the stream being written
/// \param spc is the given address space
void SleighBase::encodeSlaSpace(Encoder &encoder,AddrSpace *spc) const
{
if (spc->getType() == IPTR_INTERNAL)
encoder.openElement(sla::ELEM_SPACE_UNIQUE);
else if (spc->isOtherSpace())
encoder.openElement(sla::ELEM_SPACE_OTHER);
else
encoder.openElement(sla::ELEM_SPACE);
encoder.writeString(sla::ATTRIB_NAME,spc->getName());
encoder.writeSignedInteger(sla::ATTRIB_INDEX, spc->getIndex());
encoder.writeBool(sla::ATTRIB_BIGENDIAN, isBigEndian());
encoder.writeSignedInteger(sla::ATTRIB_DELAY, spc->getDelay());
// if (spc->getDelay() != spc->getDeadcodeDelay())
// encoder.writeSignedInteger(sla::ATTRIB_DEADCODEDELAY, spc->getDeadcodeDelay());
encoder.writeSignedInteger(sla::ATTRIB_SIZE, spc->getAddrSize());
if (spc->getWordSize() > 1)
encoder.writeSignedInteger(sla::ATTRIB_WORDSIZE, spc->getWordSize());
encoder.writeBool(sla::ATTRIB_PHYSICAL, spc->hasPhysical());
if (spc->getType() == IPTR_INTERNAL)
encoder.closeElement(sla::ELEM_SPACE_UNIQUE);
else if (spc->isOtherSpace())
encoder.closeElement(sla::ELEM_SPACE_OTHER);
else
encoder.closeElement(sla::ELEM_SPACE);
}
/// This does the bulk of the work of creating a .sla file
/// \param encoder is the stream encoder
void SleighBase::encode(Encoder &encoder) const
{
encoder.openElement(sla::ELEM_SLEIGH);
encoder.writeSignedInteger(sla::ATTRIB_VERSION, sla::FORMAT_VERSION);
encoder.writeBool(sla::ATTRIB_BIGENDIAN, isBigEndian());
encoder.writeSignedInteger(sla::ATTRIB_ALIGN, alignment);
encoder.writeUnsignedInteger(sla::ATTRIB_UNIQBASE, getUniqueBase());
if (maxdelayslotbytes > 0)
encoder.writeUnsignedInteger(sla::ATTRIB_MAXDELAY, maxdelayslotbytes);
if (unique_allocatemask != 0)
encoder.writeUnsignedInteger(sla::ATTRIB_UNIQMASK, unique_allocatemask);
if (numSections != 0)
encoder.writeUnsignedInteger(sla::ATTRIB_NUMSECTIONS, numSections);
indexer.encode(encoder);
encoder.openElement(sla::ELEM_SPACES);
encoder.writeString(sla::ATTRIB_DEFAULTSPACE, getDefaultCodeSpace()->getName());
for(int4 i=0;i<numSpaces();++i) {
AddrSpace *spc = getSpace(i);
if (spc == (AddrSpace *)0) continue;
if ((spc->getType()==IPTR_CONSTANT) ||
(spc->getType()==IPTR_FSPEC)||
(spc->getType()==IPTR_IOP)||
(spc->getType()==IPTR_JOIN))
continue;
encodeSlaSpace(encoder,spc);
}
encoder.closeElement(sla::ELEM_SPACES);
symtab.encode(encoder);
encoder.closeElement(sla::ELEM_SLEIGH);
}
/// This is identical to the functionality of decodeSpace, but the AddrSpace information is stored
/// in the .sla file format.
/// \param decoder is the stream decoder
/// \param trans is the translator object to be associated with the new space
/// \return a pointer to the initialized AddrSpace
AddrSpace *SleighBase::decodeSlaSpace(Decoder &decoder,const Translate *trans)
{
uint4 elemId = decoder.openElement();
AddrSpace *res;
int4 index = 0;
int4 addressSize = 0;
int4 delay = -1;
int4 deadcodedelay = -1;
string name;
int4 wordsize = 1;
bool bigEnd = false;
uint4 flags = 0;
for (;;) {
uint4 attribId = decoder.getNextAttributeId();
if (attribId == 0) break;
if (attribId == sla::ATTRIB_NAME) {
name = decoder.readString();
}
if (attribId == sla::ATTRIB_INDEX)
index = decoder.readSignedInteger();
else if (attribId == sla::ATTRIB_SIZE)
addressSize = decoder.readSignedInteger();
else if (attribId == sla::ATTRIB_WORDSIZE)
wordsize = decoder.readSignedInteger();
else if (attribId == sla::ATTRIB_BIGENDIAN) {
bigEnd = decoder.readBool();
}
else if (attribId == sla::ATTRIB_DELAY)
delay = decoder.readSignedInteger();
else if (attribId == sla::ATTRIB_PHYSICAL) {
if (decoder.readBool())
flags |= AddrSpace::hasphysical;
}
}
decoder.closeElement(elemId);
if (deadcodedelay == -1)
deadcodedelay = delay; // If deadcodedelay attribute not present, set it to delay
if (index == 0)
throw LowlevelError("Expecting index attribute");
if (elemId == sla::ELEM_SPACE_UNIQUE)
res = new UniqueSpace(this,trans,index,flags);
else if (elemId == sla::ELEM_SPACE_OTHER)
res = new OtherSpace(this,trans,index);
else {
if (addressSize == 0 || delay == -1 || name.size() == 0)
throw LowlevelError("Expecting size/delay/name attributes");
res = new AddrSpace(this,trans,IPTR_PROCESSOR,name,bigEnd,addressSize,wordsize,index,flags,delay,deadcodedelay);
}
return res;
}
/// This is identical in functionality to decodeSpaces but the AddrSpace information
/// is stored in the .sla file format.
/// \param decoder is the stream decoder
/// \param trans is the processor translator to be associated with the spaces
void SleighBase::decodeSlaSpaces(Decoder &decoder,const Translate *trans)
{
// The first space should always be the constant space
insertSpace(new ConstantSpace(this,trans));
uint4 elemId = decoder.openElement(sla::ELEM_SPACES);
string defname = decoder.readString(sla::ATTRIB_DEFAULTSPACE);
while(decoder.peekElement() != 0) {
AddrSpace *spc = decodeSlaSpace(decoder,trans);
insertSpace(spc);
}
decoder.closeElement(elemId);
AddrSpace *spc = getSpaceByName(defname);
if (spc == (AddrSpace *)0)
throw LowlevelError("Bad 'defaultspace' attribute: "+defname);
setDefaultCodeSpace(spc->getIndex());
}
/// This parses the main \<sleigh> tag (from a .sla file), which includes the description
/// of address spaces and the symbol table, with its associated decoding tables
/// \param decoder is the stream to decode
void SleighBase::decode(Decoder &decoder)
{
maxdelayslotbytes = 0;
unique_allocatemask = 0;
numSections = 0;
int4 version = 0;
uint4 el = decoder.openElement(sla::ELEM_SLEIGH);
uint4 attrib = decoder.getNextAttributeId();
while(attrib != 0) {
if (attrib == sla::ATTRIB_BIGENDIAN)
setBigEndian(decoder.readBool());
else if (attrib == sla::ATTRIB_ALIGN)
alignment = decoder.readSignedInteger();
else if (attrib == sla::ATTRIB_UNIQBASE)
setUniqueBase(decoder.readUnsignedInteger());
else if (attrib == sla::ATTRIB_MAXDELAY)
maxdelayslotbytes = decoder.readUnsignedInteger();
else if (attrib == sla::ATTRIB_UNIQMASK)
unique_allocatemask = decoder.readUnsignedInteger();
else if (attrib == sla::ATTRIB_NUMSECTIONS)
numSections = decoder.readUnsignedInteger();
else if (attrib == sla::ATTRIB_VERSION)
version = decoder.readSignedInteger();
attrib = decoder.getNextAttributeId();
}
if (version != sla::FORMAT_VERSION)
throw LowlevelError(".sla file has wrong format");
indexer.decode(decoder);
decodeSlaSpaces(decoder,this);
symtab.decode(decoder,this);
decoder.closeElement(el);
root = (SubtableSymbol *)symtab.getGlobalScope()->findSymbol("instruction");
vector<string> errorPairs;
buildXrefs(errorPairs);
if (!errorPairs.empty())
throw SleighError("Duplicate register pairs");
}
} // End namespace ghidra