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Memory dereference syntax working now for ia32 (att_syntax)
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John Detter committed May 27, 2016
1 parent 74fc695 commit 74a1da3
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Showing 3 changed files with 175 additions and 58 deletions.
179 changes: 128 additions & 51 deletions instructionAPI/h/Dereference.h
View file
Expand Up @@ -94,60 +94,137 @@ namespace Dyninst
addressToDereference->getUses(uses);
return;
}
/// An %InstructionAST is used by a %Dereference if it is equivalent to the
/// %Dereference or it is used by the lone child of the %Dereference
virtual bool isUsed(InstructionAST::Ptr findMe) const
{
return addressToDereference->isUsed(findMe) || *findMe == *this;
}
virtual std::string format(formatStyle) const
{
std::stringstream retVal;
#if defined(DEBUG_MEMORY_ACCESS_WIDTH)
switch(Expression::userSetValue.type)
/// An %InstructionAST is used by a %Dereference if it is equivalent to the
/// %Dereference or it is used by the lone child of the %Dereference
virtual bool isUsed(InstructionAST::Ptr findMe) const
{
case u8:
retVal << "u8 @ ";
break;
case s8:
retVal << "s8 @ ";
break;
case u16:
retVal << "u16 @ ";
break;
case s16:
retVal << "s16 @ ";
break;
case u32:
retVal << "u32 @ ";
break;
case s32:
retVal << "s32 @ ";
break;
case u64:
retVal << "u64 @ ";
break;
case s64:
retVal << "s64 @ ";
break;
case sp_float:
retVal << "float @ ";
break;
case dp_float:
retVal << "double @ ";
break;
case dbl128:
retVal << "packed double @ ";
break;
default:
retVal << "UNKNOWN SIZE @ ";
break;
return addressToDereference->isUsed(findMe) || *findMe == *this;
}

struct dereference_options_list
{
char* displacement;
char* offset;
char* base;
char* scale;
};

void analyze_ast_tree(const Expression::Ptr& ptr,
struct dereference_options_list* options, int depth) const
{
std::vector<Expression::Ptr> children;
ptr->getChildren(children);

auto it = std::begin(children);
for(;it != std::end(children);++it)
{
Expression::Ptr child = *it;
std::vector<Expression::Ptr> childs_children;
child->getChildren(childs_children);
bool leaf = childs_children.size() == 0;
const char* str = child->format().c_str();

if(!strstr(str, "+") && !strstr(str, "*"))
leaf = true;

if(leaf)
{
if(str[0] == '%')
{
if(!options->base)
options->base = strdup(str);
else if(!options->offset)
options->offset = strdup(str);
else assert(!"Too many registers in operand list!");
} else if(str[0] == '$')
{
if(!options->displacement)
options->displacement = strdup(str + 1);
else if(!options->scale)
{
options->scale = strdup(str);
} else assert(!"Too many Immediates in operand list!");
}
// std::cout << child->eval().convert<unsigned int>()
// << ":" << child->format() << " leaf? " << leaf << std::endl;
}

analyze_ast_tree(child, options, depth + 1);
}
}

virtual std::string format(formatStyle) const
{
std::stringstream retVal;
#if defined(DEBUG_MEMORY_ACCESS_WIDTH)
switch(Expression::userSetValue.type)
{
case u8:
retVal << "u8 @ ";
break;
case s8:
retVal << "s8 @ ";
break;
case u16:
retVal << "u16 @ ";
break;
case s16:
retVal << "s16 @ ";
break;
case u32:
retVal << "u32 @ ";
break;
case s32:
retVal << "s32 @ ";
break;
case u64:
retVal << "u64 @ ";
break;
case s64:
retVal << "s64 @ ";
break;
case sp_float:
retVal << "float @ ";
break;
case dp_float:
retVal << "double @ ";
break;
case dbl128:
retVal << "packed double @ ";
break;
default:
retVal << "UNKNOWN SIZE @ ";
break;
}
#endif
retVal << "(" << addressToDereference->format() << ")";
// retVal << addressToDereference->format(memoryAccessStyle);
return retVal.str();
}

struct dereference_options_list list;
memset(&list, 0,
sizeof(struct dereference_options_list));
// std::cout << std::endl;
analyze_ast_tree(addressToDereference, &list, 0);
// exit(1);

if(list.displacement && list.base && list.offset && list.scale)
{
/**
* When there's all 4 operands, dyninst gets the immediates
* flipped.
*/
retVal << (list.scale + 1) << "(" << list.offset << ", "
<< list.base << ", " << "$" << list.displacement << ")";
} else if(list.displacement && list.base && list.scale)
retVal << list.displacement << "( ," << list.base << ", "
<< list.scale << ")";
else if(list.displacement && list.base)
retVal << list.displacement << "(" << list.base << ")";
// fprintf(stderr, "return value: %s\n", retVal.str().c_str());
if(retVal.str().size() == 0)
return addressToDereference->format();
// retVal << " orig: " << addressToDereference->format();
// retVal << addressToDereference->format(memoryAccessStyle);
return retVal.str();
}

virtual bool bind(Expression* expr, const Result& value)
{
Expand Down
10 changes: 10 additions & 0 deletions instructionAPI/h/Visitor.h
View file
Expand Up @@ -60,6 +60,16 @@ namespace InstructionAPI
virtual void visit(Dereference* d) = 0;
};

// class ATTVisitor : public Visitor
// {
// public:
// std::string visitSection(void);
// void getOffset(Immediate* imm);
// void visitBase(Register* reg);
// // void visitIndex(Immediate* imm);
// void visitScale(Immediate* imm);
// };

}
}

Expand Down
44 changes: 37 additions & 7 deletions instructionAPI/src/Operand.C
View file
Expand Up @@ -111,18 +111,48 @@ namespace Dyninst
}
}
}

static void indt_ast_tree(int depth)
{
for(int x = 0;x < depth;x++)
cout << "\t";
}

void print_ast_tree(Expression::Ptr& ptr, int depth)
{
std::vector<Expression::Ptr> children;
ptr->getChildren(children);

auto it = std::begin(children);
for(;it != std::end(children);++it)
{
Expression::Ptr child = *it;
indt_ast_tree(depth);
cout << child->eval().convert<unsigned int>();

print_ast_tree(child, depth + 1);
}
}

INSTRUCTION_EXPORT std::string Operand::format(Architecture arch, Address addr) const
{
if(!op_value) return "ERROR: format() called on empty operand!";
if (addr) {
Expression::Ptr thePC = Expression::Ptr(new RegisterAST(MachRegister::getPC(arch)));
op_value->bind(thePC.get(), Result(u32, addr));
Result res = op_value->eval();
if (res.defined) {
stringstream ret;
ret << hex << res.convert<unsigned>() << dec;
return ret.str();
}

cout << endl;
print_ast_tree(thePC, 0);
exit(1);



// op_value->bind(thePC.get(), Result(u32, addr));
// Result res = op_value->eval();
// if (res.defined) {
// stringstream ret;
// ret << hex << res.convert<unsigned>() << dec;
// return ret.str();
// }
}
return op_value->format();
}
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