#include "stdafx.h" #include #include #include "ExpressionEvaluator.h" #include "Console.h" #include "Debugger.h" #include "MemoryDumper.h" #include "Disassembler.h" #include "LabelManager.h" #include "../Utilities/HexUtilities.h" const vector ExpressionEvaluator::_binaryOperators = { { "*", "/", "%", "+", "-", "<<", ">>", "<", "<=", ">", ">=", "==", "!=", "&", "^", "|", "&&", "||" } }; const vector ExpressionEvaluator::_binaryPrecedence = { { 10, 10, 10, 9, 9, 8, 8, 7, 7, 7, 7, 6, 6, 5, 4, 3, 2, 1 } }; const vector ExpressionEvaluator::_unaryOperators = { { "+", "-", "~", "!", ":" } }; const vector ExpressionEvaluator::_unaryPrecedence = { { 11, 11, 11, 11, 11 } }; const std::unordered_set ExpressionEvaluator::_operators = { { "*", "/", "%", "+", "-", "<<", ">>", "<", "<=", ">", ">=", "==", "!=", "&", "^", "|", "&&", "||", "~", "!", "(", ")", "{", "}", "[", "]", ":" } }; bool ExpressionEvaluator::IsOperator(string token, int &precedence, bool unaryOperator) { if(unaryOperator) { for(size_t i = 0, len = _unaryOperators.size(); i < len; i++) { if(token.compare(_unaryOperators[i]) == 0) { precedence = _unaryPrecedence[i]; return true; } } } else { for(size_t i = 0, len = _binaryOperators.size(); i < len; i++) { if(token.compare(_binaryOperators[i]) == 0) { precedence = _binaryPrecedence[i]; return true; } } } return false; } EvalOperators ExpressionEvaluator::GetOperator(string token, bool unaryOperator) { if(unaryOperator) { for(size_t i = 0, len = _unaryOperators.size(); i < len; i++) { if(token.compare(_unaryOperators[i]) == 0) { return (EvalOperators)(EvalOperators::Plus + i); } } } else { for(size_t i = 0, len = _binaryOperators.size(); i < len; i++) { if(token.compare(_binaryOperators[i]) == 0) { return (EvalOperators)(EvalOperators::Multiplication + i); } } } return EvalOperators::Addition; } bool ExpressionEvaluator::CheckSpecialTokens(string expression, size_t &pos, string &output, ExpressionData &data) { string token; size_t initialPos = pos; size_t len = expression.size(); do { char c = std::tolower(expression[pos]); if((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || c == '_' || c == '@') { //Only letters, numbers and underscore are allowed in code labels token += c; pos++; } else { break; } } while(pos < len); if(token == "a") { output += std::to_string((int64_t)EvalValues::RegA); } else if(token == "x") { output += std::to_string((int64_t)EvalValues::RegX); } else if(token == "y") { output += std::to_string((int64_t)EvalValues::RegY); } else if(token == "ps") { output += std::to_string((int64_t)EvalValues::RegPS); } else if(token == "pscarry") { output += std::to_string((int64_t)EvalValues::RegPS_Carry); } else if(token == "pszero") { output += std::to_string((int64_t)EvalValues::RegPS_Zero); } else if(token == "psinterrupt") { output += std::to_string((int64_t)EvalValues::RegPS_Interrupt); } else if(token == "psdecimal") { output += std::to_string((int64_t)EvalValues::RegPS_Decimal); } else if(token == "psoverflow") { output += std::to_string((int64_t)EvalValues::RegPS_Overflow); } else if(token == "psnegative") { output += std::to_string((int64_t)EvalValues::RegPS_Negative); } else if(token == "sp") { output += std::to_string((int64_t)EvalValues::RegSP); } else if(token == "pc") { output += std::to_string((int64_t)EvalValues::RegPC); } else if(token == "oppc") { output += std::to_string((int64_t)EvalValues::RegOpPC); } else if(token == "previousoppc") { output += std::to_string((int64_t)EvalValues::PreviousOpPC); } else if(token == "frame") { output += std::to_string((int64_t)EvalValues::PpuFrameCount); } else if(token == "cycle") { output += std::to_string((int64_t)EvalValues::PpuCycle); } else if(token == "scanline") { output += std::to_string((int64_t)EvalValues::PpuScanline); } else if(token == "irq") { output += std::to_string((int64_t)EvalValues::Irq); } else if(token == "nmi") { output += std::to_string((int64_t)EvalValues::Nmi); } else if(token == "verticalblank") { output += std::to_string((int64_t)EvalValues::VerticalBlank); } else if(token == "sprite0hit") { output += std::to_string((int64_t)EvalValues::Sprite0Hit); } else if(token == "spriteoverflow") { output += std::to_string((int64_t)EvalValues::SpriteOverflow); } else if(token == "value") { output += std::to_string((int64_t)EvalValues::Value); } else if(token == "address") { output += std::to_string((int64_t)EvalValues::Address); } else if(token == "iswrite") { output += std::to_string((int64_t)EvalValues::IsWrite); } else if(token == "isread") { output += std::to_string((int64_t)EvalValues::IsRead); } else if(token == "branched") { output += std::to_string((int64_t)EvalValues::Branched); } else { string originalExpression = expression.substr(initialPos, pos - initialPos); bool validLabel = _debugger->GetLabelManager()->ContainsLabel(originalExpression); if(!validLabel) { //Check if a multi-byte label exists for this name string label = originalExpression + "+0"; validLabel = _debugger->GetLabelManager()->ContainsLabel(label); } if(validLabel) { data.Labels.push_back(originalExpression); output += std::to_string(EvalValues::FirstLabelIndex + data.Labels.size() - 1); } else { return false; } } return true; } string ExpressionEvaluator::GetNextToken(string expression, size_t& pos, ExpressionData& data, bool& success, bool previousTokenIsOp) { string output; success = true; char c = std::tolower(expression[pos]); if(c == '$') { //Hex numbers pos++; for(size_t len = expression.size(); pos < len; pos++) { c = std::tolower(expression[pos]); if((c >= '0' && c <= '9') || (c >= 'a' && c <= 'f')) { output += c; } else { break; } } if(output.empty()) { //No numbers followed the hex mark, this isn't a valid expression success = false; } output = std::to_string((uint32_t)HexUtilities::FromHex(output)); } else if(c == '%' && previousTokenIsOp) { //Binary numbers pos++; for(size_t len = expression.size(); pos < len; pos++) { c = std::tolower(expression[pos]); if(c == '0' || c == '1') { output += c; } else { break; } } if(output.empty()) { //No numbers followed the binary mark, this isn't a valid expression success = false; } uint32_t value = 0; for(size_t i = 0; i < output.size(); i++) { value <<= 1; value |= output[i] == '1' ? 1 : 0; } output = std::to_string(value); } else if(c >= '0' && c <= '9') { //Regular numbers for(size_t len = expression.size(); pos < len; pos++) { c = std::tolower(expression[pos]); if(c >= '0' && c <= '9') { output += c; } else { break; } } } else if((c < 'a' || c > 'z') && c != '_' && c != '@') { //Operators string operatorToken; for(size_t len = expression.size(); pos < len; pos++) { c = std::tolower(expression[pos]); operatorToken += c; if(output.empty() || _operators.find(operatorToken) != _operators.end()) { //If appending the next char results in a valid operator, append it (or if this is the first character) output += c; } else { //Reached the end of the operator, return break; } } } else { //Special tokens and labels success = CheckSpecialTokens(expression, pos, output, data); } return output; } bool ExpressionEvaluator::ProcessSpecialOperator(EvalOperators evalOp, std::stack &opStack, std::stack &precedenceStack, vector &outputQueue) { if(opStack.empty()) { return false; } while(opStack.top() != evalOp) { outputQueue.push_back(opStack.top()); opStack.pop(); precedenceStack.pop(); if(opStack.empty()) { return false; } } if(evalOp != EvalOperators::Parenthesis) { outputQueue.push_back(opStack.top()); } opStack.pop(); precedenceStack.pop(); return true; } bool ExpressionEvaluator::ToRpn(string expression, ExpressionData &data) { std::stack opStack = std::stack(); std::stack precedenceStack; size_t position = 0; int parenthesisCount = 0; int bracketCount = 0; int braceCount = 0; bool previousTokenIsOp = true; bool operatorExpected = false; bool operatorOrEndTokenExpected = false; while(true) { bool success = true; string token = GetNextToken(expression, position, data, success, previousTokenIsOp); if(!success) { return false; } if(token.empty()) { break; } bool requireOperator = operatorExpected; bool requireOperatorOrEndToken = operatorOrEndTokenExpected; bool unaryOperator = previousTokenIsOp; operatorExpected = false; operatorOrEndTokenExpected = false; previousTokenIsOp = false; int precedence = 0; if(IsOperator(token, precedence, unaryOperator)) { EvalOperators op = GetOperator(token, unaryOperator); bool rightAssociative = unaryOperator; while(!opStack.empty() && ((rightAssociative && precedence < precedenceStack.top()) || (!rightAssociative && precedence <= precedenceStack.top()))) { //Pop operators from the stack until we find something with higher priority (or empty the stack) data.RpnQueue.push_back(opStack.top()); opStack.pop(); precedenceStack.pop(); } opStack.push(op); precedenceStack.push(precedence); previousTokenIsOp = true; } else if(requireOperator) { //We needed an operator, and got something else, this isn't a valid expression (e.g "(3)4" or "[$00]22") return false; } else if(requireOperatorOrEndToken && token[0] != ')' && token[0] != ']' && token[0] != '}') { //We needed an operator or close token - this isn't a valid expression (e.g "%1134") return false; } else if(token[0] == '(') { parenthesisCount++; opStack.push(EvalOperators::Parenthesis); precedenceStack.push(0); previousTokenIsOp = true; } else if(token[0] == ')') { parenthesisCount--; if(!ProcessSpecialOperator(EvalOperators::Parenthesis, opStack, precedenceStack, data.RpnQueue)) { return false; } operatorOrEndTokenExpected = true; } else if(token[0] == '[') { bracketCount++; opStack.push(EvalOperators::Bracket); precedenceStack.push(0); } else if(token[0] == ']') { bracketCount--; if(!ProcessSpecialOperator(EvalOperators::Bracket, opStack, precedenceStack, data.RpnQueue)) { return false; } operatorOrEndTokenExpected = true; } else if(token[0] == '{') { braceCount++; opStack.push(EvalOperators::Braces); precedenceStack.push(0); } else if(token[0] == '}') { braceCount--; if(!ProcessSpecialOperator(EvalOperators::Braces, opStack, precedenceStack, data.RpnQueue)){ return false; } operatorOrEndTokenExpected = true; } else { if(token[0] < '0' || token[0] > '9') { return false; } else { data.RpnQueue.push_back(std::stoll(token)); operatorOrEndTokenExpected = true; } } } if(braceCount || bracketCount || parenthesisCount) { //Mismatching number of brackets/braces/parenthesis return false; } while(!opStack.empty()) { data.RpnQueue.push_back(opStack.top()); opStack.pop(); } return true; } int32_t ExpressionEvaluator::Evaluate(ExpressionData &data, DebugState &state, EvalResultType &resultType, OperationInfo &operationInfo) { if(data.RpnQueue.empty()) { resultType = EvalResultType::Invalid; return 0; } int pos = 0; int64_t right = 0; int64_t left = 0; resultType = EvalResultType::Numeric; for(size_t i = 0, len = data.RpnQueue.size(); i < len; i++) { int64_t token = data.RpnQueue[i]; if(token >= EvalValues::RegA) { //Replace value with a special value if(token >= EvalValues::FirstLabelIndex) { int64_t labelIndex = token - EvalValues::FirstLabelIndex; if((size_t)labelIndex < data.Labels.size()) { token = _debugger->GetLabelManager()->GetLabelRelativeAddress(data.Labels[(uint32_t)labelIndex]); if(token < -1) { //Label doesn't exist, try to find a matching multi-byte label string label = data.Labels[(uint32_t)labelIndex] + "+0"; token = _debugger->GetLabelManager()->GetLabelRelativeAddress(label); } } else { token = -2; } if(token < 0) { //Label is no longer valid resultType = token == -1 ? EvalResultType::OutOfScope : EvalResultType::Invalid; return 0; } } else { switch(token) { case EvalValues::RegA: token = state.CPU.A; break; case EvalValues::RegX: token = state.CPU.X; break; case EvalValues::RegY: token = state.CPU.Y; break; case EvalValues::RegSP: token = state.CPU.SP; break; case EvalValues::RegPS: token = state.CPU.PS; break; case EvalValues::RegPC: token = state.CPU.PC; break; case EvalValues::RegOpPC: token = state.CPU.DebugPC; break; case EvalValues::PpuFrameCount: token = state.PPU.FrameCount; break; case EvalValues::PpuCycle: token = state.PPU.Cycle; break; case EvalValues::PpuScanline: token = state.PPU.Scanline; break; case EvalValues::Nmi: token = state.CPU.NMIFlag; resultType = EvalResultType::Boolean; break; case EvalValues::Irq: token = state.CPU.IRQFlag; resultType = EvalResultType::Boolean; break; case EvalValues::Value: token = operationInfo.Value; break; case EvalValues::Address: token = operationInfo.Address; break; case EvalValues::IsWrite: token = operationInfo.OperationType == MemoryOperationType::Write || operationInfo.OperationType == MemoryOperationType::DummyWrite; break; case EvalValues::IsRead: token = operationInfo.OperationType == MemoryOperationType::Read || operationInfo.OperationType == MemoryOperationType::DummyRead; break; case EvalValues::PreviousOpPC: token = state.CPU.PreviousDebugPC; break; case EvalValues::Sprite0Hit: token = state.PPU.StatusFlags.Sprite0Hit; resultType = EvalResultType::Boolean; break; case EvalValues::SpriteOverflow: token = state.PPU.StatusFlags.SpriteOverflow; resultType = EvalResultType::Boolean; break; case EvalValues::VerticalBlank: token = state.PPU.StatusFlags.VerticalBlank; resultType = EvalResultType::Boolean; break; case EvalValues::Branched: token = Disassembler::IsJump(_debugger->GetMemoryDumper()->GetMemoryValue(DebugMemoryType::CpuMemory, state.CPU.PreviousDebugPC, true)); resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Carry: token = (state.CPU.PS & PSFlags::Carry) != 0; resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Zero: token = (state.CPU.PS & PSFlags::Zero) != 0; resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Interrupt: token = (state.CPU.PS & PSFlags::Interrupt) != 0; resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Decimal: token = (state.CPU.PS & PSFlags::Decimal) != 0; resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Overflow: token = (state.CPU.PS & PSFlags::Overflow) != 0; resultType = EvalResultType::Boolean; break; case EvalValues::RegPS_Negative: token = (state.CPU.PS & PSFlags::Negative) != 0; resultType = EvalResultType::Boolean; break; } } } else if(token >= EvalOperators::Multiplication) { right = operandStack[--pos]; if(pos > 0 && token <= EvalOperators::LogicalOr) { //Only do this for binary operators left = operandStack[--pos]; } resultType = EvalResultType::Numeric; switch(token) { case EvalOperators::Multiplication: token = left * right; break; case EvalOperators::Division: if(right == 0) { resultType = EvalResultType::DivideBy0; return 0; } token = left / right; break; case EvalOperators::Modulo: if(right == 0) { resultType = EvalResultType::DivideBy0; return 0; } token = left % right; break; case EvalOperators::Addition: token = left + right; break; case EvalOperators::Substration: token = left - right; break; case EvalOperators::ShiftLeft: token = left << right; break; case EvalOperators::ShiftRight: token = left >> right; break; case EvalOperators::SmallerThan: token = left < right; resultType = EvalResultType::Boolean; break; case EvalOperators::SmallerOrEqual: token = left <= right; resultType = EvalResultType::Boolean; break; case EvalOperators::GreaterThan: token = left > right; resultType = EvalResultType::Boolean; break; case EvalOperators::GreaterOrEqual: token = left >= right; resultType = EvalResultType::Boolean; break; case EvalOperators::Equal: token = left == right; resultType = EvalResultType::Boolean; break; case EvalOperators::NotEqual: token = left != right; resultType = EvalResultType::Boolean; break; case EvalOperators::BinaryAnd: token = left & right; break; case EvalOperators::BinaryXor: token = left ^ right; break; case EvalOperators::BinaryOr: token = left | right; break; case EvalOperators::LogicalAnd: token = left && right; resultType = EvalResultType::Boolean; break; case EvalOperators::LogicalOr: token = left || right; resultType = EvalResultType::Boolean; break; //Unary operators case EvalOperators::Plus: token = right; break; case EvalOperators::Minus: token = -right; break; case EvalOperators::BinaryNot: token = ~right; break; case EvalOperators::LogicalNot: token = !right; break; case EvalOperators::AbsoluteAddress: { if(right >= 0) { AddressTypeInfo addressInfo; _debugger->GetAbsoluteAddressAndType((uint32_t)right, &addressInfo); token = addressInfo.Address; } else { token = -1; } break; } case EvalOperators::Bracket: token = _debugger->GetMemoryDumper()->GetMemoryValue(DebugMemoryType::CpuMemory, (uint32_t)right); break; case EvalOperators::Braces: token = _debugger->GetMemoryDumper()->GetMemoryValueWord(DebugMemoryType::CpuMemory, (uint32_t)right); break; default: throw std::runtime_error("Invalid operator"); } } operandStack[pos++] = token; } return (int32_t)operandStack[0]; } ExpressionEvaluator::ExpressionEvaluator(Debugger* debugger) { _debugger = debugger; } ExpressionData ExpressionEvaluator::GetRpnList(string expression, bool &success) { ExpressionData* cachedData = PrivateGetRpnList(expression, success); if(cachedData) { return *cachedData; } else { return ExpressionData(); } } ExpressionData* ExpressionEvaluator::PrivateGetRpnList(string expression, bool& success) { ExpressionData *cachedData = nullptr; { LockHandler lock = _cacheLock.AcquireSafe(); auto result = _cache.find(expression); if(result != _cache.end()) { cachedData = &(result->second); } } if(cachedData == nullptr) { string fixedExp = expression; fixedExp.erase(std::remove(fixedExp.begin(), fixedExp.end(), ' '), fixedExp.end()); ExpressionData data; success = ToRpn(fixedExp, data); if(success) { LockHandler lock = _cacheLock.AcquireSafe(); _cache[expression] = data; cachedData = &_cache[expression]; } } else { success = true; } return cachedData; } int32_t ExpressionEvaluator::PrivateEvaluate(string expression, DebugState &state, EvalResultType &resultType, OperationInfo &operationInfo, bool& success) { success = true; ExpressionData *cachedData = PrivateGetRpnList(expression, success); if(!success) { resultType = EvalResultType::Invalid; return 0; } return Evaluate(*cachedData, state, resultType, operationInfo); } int32_t ExpressionEvaluator::Evaluate(string expression, DebugState &state, EvalResultType &resultType, OperationInfo &operationInfo) { try { bool success; int32_t result = PrivateEvaluate(expression, state, resultType, operationInfo, success); if(success) { return result; } } catch(std::exception&) { } resultType = EvalResultType::Invalid; return 0; } bool ExpressionEvaluator::Validate(string expression) { try { DebugState state; EvalResultType type; OperationInfo operationInfo; bool success; PrivateEvaluate(expression, state, type, operationInfo, success); return success; } catch(std::exception&) { return false; } } #if _DEBUG #include void ExpressionEvaluator::RunTests() { //Some basic unit tests to run in debug mode auto test = [=](string expr, EvalResultType expectedType, int expectedResult) { DebugState state = { 0 }; OperationInfo opInfo = { 0 }; EvalResultType type; int32_t result = Evaluate(expr, state, type, opInfo); assert(type == expectedType); assert(result == expectedResult); }; test("1 - -1", EvalResultType::Numeric, 2); test("1 - (-1)", EvalResultType::Numeric, 2); test("1 - -(-1)", EvalResultType::Numeric, 0); test("(0 - 1) == -1 && 5 < 10", EvalResultType::Boolean, true); test("(0 - 1) == 0 || 5 < 10", EvalResultType::Boolean, true); test("(0 - 1) == 0 || 5 < -10", EvalResultType::Boolean, false); test("(0 - 1) == 0 || 15 < 10", EvalResultType::Boolean, false); test("10 != $10", EvalResultType::Boolean, true); test("10 == $A", EvalResultType::Boolean, true); test("10 == $0A", EvalResultType::Boolean, true); test("(0 - 1 == 0 || 15 < 10", EvalResultType::Invalid, 0); test("10 / 0", EvalResultType::DivideBy0, 0); test("x + 5", EvalResultType::Numeric, 5); test("x == 0", EvalResultType::Boolean, true); test("x == y", EvalResultType::Boolean, true); test("x == y == scanline", EvalResultType::Boolean, false); //because (x == y) is true, and true != scanline test("x == y && !(a == x)", EvalResultType::Boolean, false); test("(~0 & ~1) & $FFF == $FFE", EvalResultType::Numeric, 0); //because of operator priority (& is done after ==) test("((~0 & ~1) & $FFF) == $FFE", EvalResultType::Boolean, true); test("1+3*3+10/(3+4)", EvalResultType::Numeric, 11); test("(1+3*3+10)/(3+4)", EvalResultType::Numeric, 2); test("(1+3*3+10)/3+4", EvalResultType::Numeric, 10); test("{$4100}", EvalResultType::Numeric, 0x4141); test("[$4100]", EvalResultType::Numeric, 0x41); test("[$45]3", EvalResultType::Invalid, 0); test("($45)3", EvalResultType::Invalid, 0); test("($45]", EvalResultType::Invalid, 0); test("%11", EvalResultType::Numeric, 3); test("%011", EvalResultType::Numeric, 3); test("%1011", EvalResultType::Numeric, 11); test("%12", EvalResultType::Invalid, 0); test("10 % 5", EvalResultType::Numeric, 0); test("%100 % 5", EvalResultType::Numeric, 4); test("%100%5", EvalResultType::Numeric, 4); test("%10(10)", EvalResultType::Invalid, 0); test("10%4*10", EvalResultType::Numeric, 20); test("(5+5)%3", EvalResultType::Numeric, 1); test("11%%10", EvalResultType::Numeric, 1); //11 modulo of 2 in binary (%10) test(":$00", EvalResultType::Numeric, 0); test(":50", EvalResultType::Numeric, 50); test(":$50", EvalResultType::Numeric, 0x50); test(":($1FFF+1)", EvalResultType::Numeric, -1); test(":$1FFF+1", EvalResultType::Numeric, 0x800); test("1+:$100", EvalResultType::Numeric, 0x101); test("[$4100+[$4100]]", EvalResultType::Numeric, 0x41); test("-($10+[$4100])", EvalResultType::Numeric, -0x51); } #endif