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mirror of https://github.com/TomHarte/CLK.git synced 2024-07-04 18:29:40 +00:00

Adjusted semantics to allow for more complicated mappings, e.g. whereby supplied data repeats itself within a range.

This commit is contained in:
Thomas Harte 2017-02-27 07:49:33 -05:00
parent b24cd00a39
commit 837216ee9a
2 changed files with 31 additions and 19 deletions

View File

@ -16,18 +16,18 @@ struct PartialDisassembly {
std::vector<uint16_t> remaining_entry_points;
};
static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<uint8_t> &memory, uint16_t start_address, uint16_t entry_point, uint16_t address_mask)
static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<uint8_t> &memory, const std::function<size_t(uint16_t)> &address_mapper, uint16_t entry_point)
{
disassembly.disassembly.internal_calls.insert(start_address);
uint16_t address = entry_point & address_mask;
disassembly.disassembly.internal_calls.insert(entry_point);
uint16_t address = entry_point;
while(1)
{
uint16_t local_address = address - start_address;
size_t local_address = address_mapper(address);
if(local_address >= memory.size()) return;
struct Instruction instruction;
instruction.address = address;
address = (address + 1) & address_mask;
address++;
// get operation
uint8_t operation = memory[local_address];
@ -235,7 +235,7 @@ static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<
case Instruction::IndexedIndirectX: case Instruction::IndirectIndexedY:
case Instruction::Relative:
{
uint16_t operand_address = address - start_address;
size_t operand_address = address_mapper(address);
if(operand_address >= memory.size()) return;
address++;
@ -247,11 +247,12 @@ static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<
case Instruction::Absolute: case Instruction::AbsoluteX: case Instruction::AbsoluteY:
case Instruction::Indirect:
{
uint16_t operand_address = address - start_address;
if(operand_address >= memory.size()-1) return;
size_t low_operand_address = address_mapper(address);
size_t high_operand_address = address_mapper(address + 1);
if(low_operand_address >= memory.size() || high_operand_address >= memory.size()) return;
address += 2;
instruction.operand = memory[operand_address] | (uint16_t)(memory[operand_address + 1] << 8);
instruction.operand = memory[low_operand_address] | (uint16_t)(memory[high_operand_address] << 8);
}
break;
}
@ -262,7 +263,8 @@ static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<
// TODO: something wider-ranging than this
if(instruction.addressing_mode == Instruction::Absolute || instruction.addressing_mode == Instruction::ZeroPage)
{
bool is_external = (instruction.operand&address_mask) < start_address || (instruction.operand&address_mask) >= start_address + memory.size();
size_t mapped_address = address_mapper(instruction.operand);
bool is_external = mapped_address >= memory.size();
switch(instruction.operation)
{
@ -297,23 +299,23 @@ static void AddToDisassembly(PartialDisassembly &disassembly, const std::vector<
if(instruction.operation == Instruction::BRK) return; // TODO: check whether IRQ vector is within memory range
if(instruction.operation == Instruction::JSR)
{
disassembly.remaining_entry_points.push_back(instruction.operand & address_mask);
disassembly.remaining_entry_points.push_back(instruction.operand);
}
if(instruction.operation == Instruction::JMP)
{
if(instruction.addressing_mode == Instruction::Absolute)
disassembly.remaining_entry_points.push_back(instruction.operand & address_mask);
disassembly.remaining_entry_points.push_back(instruction.operand);
return;
}
if(instruction.addressing_mode == Instruction::Relative)
{
uint16_t destination = (uint16_t)(address + (int8_t)instruction.operand);
disassembly.remaining_entry_points.push_back(destination & address_mask);
disassembly.remaining_entry_points.push_back(destination);
}
}
}
Disassembly StaticAnalyser::MOS6502::Disassemble(const std::vector<uint8_t> &memory, uint16_t start_address, std::vector<uint16_t> entry_points, uint16_t address_mask)
Disassembly StaticAnalyser::MOS6502::Disassemble(const std::vector<uint8_t> &memory, const std::function<size_t(uint16_t)> &address_mapper, std::vector<uint16_t> entry_points)
{
PartialDisassembly partialDisassembly;
partialDisassembly.remaining_entry_points = entry_points;
@ -321,18 +323,26 @@ Disassembly StaticAnalyser::MOS6502::Disassemble(const std::vector<uint8_t> &mem
while(!partialDisassembly.remaining_entry_points.empty())
{
// pull the next entry point from the back of the vector
uint16_t next_entry_point = partialDisassembly.remaining_entry_points.back() & address_mask;
uint16_t next_entry_point = partialDisassembly.remaining_entry_points.back();
partialDisassembly.remaining_entry_points.pop_back();
// if that address has already bene visited, forget about it
if(partialDisassembly.disassembly.instructions_by_address.find(next_entry_point) != partialDisassembly.disassembly.instructions_by_address.end()) continue;
// if it's outgoing, log it as such and forget about it; otherwise disassemble
if(next_entry_point < start_address || next_entry_point >= start_address + memory.size())
size_t mapped_entry_point = address_mapper(next_entry_point);
if(mapped_entry_point >= memory.size())
partialDisassembly.disassembly.outward_calls.insert(next_entry_point);
else
AddToDisassembly(partialDisassembly, memory, start_address, next_entry_point, address_mask);
AddToDisassembly(partialDisassembly, memory, address_mapper, next_entry_point);
}
return std::move(partialDisassembly.disassembly);
}
std::function<size_t(uint16_t)> StaticAnalyser::MOS6502::OffsetMapper(uint16_t start_address)
{
return [start_address](uint16_t argument) {
return (size_t)(argument - start_address);
};
}

View File

@ -10,10 +10,11 @@
#define Disassembler6502_hpp
#include <cstdint>
#include <functional>
#include <map>
#include <memory>
#include <set>
#include <vector>
#include <map>
namespace StaticAnalyser {
namespace MOS6502 {
@ -69,7 +70,8 @@ struct Disassembly {
std::set<uint16_t> internal_stores, internal_loads, internal_modifies;
};
Disassembly Disassemble(const std::vector<uint8_t> &memory, uint16_t start_address, std::vector<uint16_t> entry_points, uint16_t address_mask = 0xffff);
Disassembly Disassemble(const std::vector<uint8_t> &memory, const std::function<size_t(uint16_t)> &address_mapper, std::vector<uint16_t> entry_points);
std::function<size_t(uint16_t)> OffsetMapper(uint16_t start_address);
}
}