diff options
1 files changed, 191 insertions, 151 deletions
| -rw-r--r-- | spasm/src/spasm.cpp | 342 |
diff --git a/spasm/src/spasm.cpp b/spasm/src/spasm.cpp index 857143f..60f7531 100644 --- a/spasm/src/spasm.cpp +++ b/spasm/src/spasm.cpp @@ -1,40 +1,12 @@ #include <algorithm> -#include <iostream> #include <cassert> +#include <iostream> #include "spasm.hpp" namespace SpasmImpl { - - -PC_t Spasm::op_size = 21; -// Be sure the same number is on the previous and next lines -Operation Spasm::operations[] = {NULL, - &Spasm::push, - &Spasm::pop, - &Spasm::dup, - &Spasm::print, - &Spasm::read, - &Spasm::plus, - &Spasm::minus, - &Spasm::multiply, - &Spasm::divide, - &Spasm::modulus, - &Spasm::gotrue, - &Spasm::gofalse, - &Spasm::go, - &Spasm::call, - &Spasm::ret, - &Spasm::load, - &Spasm::store, - &Spasm::less, - &Spasm::lesseq}; - -Spasm::Spasm() - : pc(0), bc_size(0), bytecode(NULL), istr(&std::cin), ostr(&std::cout) -{ -} +Spasm::Spasm() {} /*! ** Constructs new Spasm object @@ -48,92 +20,155 @@ Spasm::Spasm(PC_t _bc_size, const byte* _bytecode, std::istream& _istr, std::ostream& _ostr) - : pc(0), bc_size(_bc_size), istr(&_istr), ostr(&_ostr) -{ - bytecode = new byte[bc_size]; - std::copy(_bytecode, _bytecode + bc_size, bytecode); -} - -Spasm::Spasm(const Spasm& m) - : pc(m.pc), - bc_size(m.bc_size), - data_stack(m.data_stack), - return_stack(m.return_stack), - frame(m.frame), - istr(m.istr), - ostr(m.ostr) + : m_PC(0), + m_ByteCode(_bytecode, _bytecode + _bc_size), + istr(&_istr), + ostr(&_ostr) { - copybc(m); + data_stack.resize(1024); + m_SP = &data_stack[0]; + m_FP = &data_stack[0]; } -Spasm::~Spasm() -{ - deleteobj(); -} - -Spasm& Spasm::operator=(const Spasm& m) -{ - if (this != &m) - { - deleteobj(); - data_stack = m.data_stack; - return_stack = m.return_stack; - frame = m.frame; - istr = m.istr; - ostr = m.ostr; - copybc(m); - } - return *this; -} +Spasm::~Spasm() {} /*! -** Copies the bytecode of another machine m -** -** \param m - the machine from the bytecode is copied -*/ - -void Spasm::copybc(const Spasm& m) -{ - bytecode = new byte[bc_size]; - std::copy(m.bytecode, m.bytecode + bc_size, bytecode); -} - -/*! -** Deletes the machine -*/ -void Spasm::deleteobj() -{ - if (bytecode) - delete[] bytecode; -} - -/*! -** Starts the machine. The machine stops if it reaches an invalid opcode +** Runs the machine. The machine stops if it reaches an invalid opcode ** or opcode 0 or the pc reaches beyond the end of the bytecode. +** @return error code for success or failure */ -void Spasm::run() +Spasm::RunResult Spasm::run() { - while (pc < bc_size) + const auto size = m_ByteCode.size(); + while (m_PC < size) { - if (bytecode[pc] > 0 && bytecode[pc] < op_size) - (this->*operations[bytecode[pc]])(); - else + const auto instruction = m_ByteCode[m_PC++]; + const auto opcode = OpCodes(instruction & 0x3f); + const auto size = instruction >> 6; + assert(size == 0 && "no long args yet"); + (void)size; + switch (opcode) { - std::cerr << "opcode got to " << int(bytecode[pc]) << std::endl; - break; + case OpCodes::Halt: + return RunResult::Success; + case OpCodes::Dup: + dup(); + break; + case OpCodes::Pop: + pop(); + break; + case OpCodes::PopTo: + break; + case OpCodes::Push: + { + const auto arg0 = read_reg(size); + push(arg0); + break; + } + case OpCodes::Print: + { + const auto arg0 = read_reg(size); + print(arg0); + break; + } + case OpCodes::Read: + { + const auto arg0 = read_reg(size); + read(arg0); + break; + } + case OpCodes::Jump: + { + const auto arg0 = read_reg(size); + go(arg0); + break; + } + case OpCodes::JumpT: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + gotrue(arg0, arg1); + break; + } + case OpCodes::JumpF: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + gofalse(arg0, arg1); + break; + } + case OpCodes::Add: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + plus(arg0, arg1, arg2); + break; + } + case OpCodes::Sub: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + minus(arg0, arg1, arg2); + break; + } + case OpCodes::Mul: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + multiply(arg0, arg1, arg2); + break; + } + case OpCodes::Div: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + divide(arg0, arg1, arg2); + break; + } + case OpCodes::Mod: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + modulus(arg0, arg1, arg2); + break; + } + case OpCodes::Less: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + less(arg0, arg1, arg2); + break; + } + case OpCodes::LessEq: + { + const auto arg0 = read_reg(size); + const auto arg1 = read_reg(size); + const auto arg2 = read_reg(size); + lesseq(arg0, arg1, arg2); + break; + } + default: + { + std::cerr << opcode << ": not implemented" << std::endl; + return RunResult::NotImplemented; + } } - ++pc; } + return RunResult::Success; } /*! ** Pushes the next data_t object on the data stack */ -void Spasm::push() +void Spasm::push(reg_t reg) { - ++pc; - push_data(*reinterpret_cast<data_t*>(bytecode + pc)); - pc += sizeof(data_t) - 1; + push_data(get_local(reg)); } /*! @@ -141,7 +176,7 @@ void Spasm::push() */ void Spasm::pop() { - data_stack.pop_back(); + --m_SP; } /*! @@ -149,83 +184,72 @@ void Spasm::pop() */ void Spasm::dup() { - push_data(data_stack.back()); + push_data(*(m_SP - 1)); } /*! ** Reads a data_t object from the input stream and pushes it on the data ** stack. */ -void Spasm::read() +void Spasm::read(reg_t reg) { data_t x; *istr >> x; - push_data(x); + set_local(reg, x); } /*! ** Pops a data_t object from the data stack and prints it on the output ** stream. */ -void Spasm::print() +void Spasm::print(reg_t reg) { - *ostr << data_stack.back(); - pop(); + *ostr << get_local(reg); } /*! ** Pops two data objects from the data stack and pushes their sum on the ** data stack. */ -void Spasm::plus() +void Spasm::plus(reg_t a0, reg_t a1, reg_t a2) { - data_t x, y = pop_data(); - x = pop_data(); - push_data(x + y); + set_local(a0, get_local(a1) + get_local(a2)); } /*! ** Pops two data objects from the data stack and pushes their difference ** on the data stack. */ -void Spasm::minus() +void Spasm::minus(reg_t a0, reg_t a1, reg_t a2) { - data_t x, y = pop_data(); - x = pop_data(); - push_data(x - y); + set_local(a0, get_local(a1) - get_local(a2)); } /*! ** Pops two data objects from the data stack and pushes their product ** on the data stack. */ -void Spasm::multiply() +void Spasm::multiply(reg_t a0, reg_t a1, reg_t a2) { - data_t y = pop_data(), - x = pop_data(); - push_data(x * y); + set_local(a0, get_local(a1) * get_local(a2)); } /*! ** Pops two data objects from the data stack and pushes their division ** on the data stack. */ -void Spasm::divide() +void Spasm::divide(reg_t a0, reg_t a1, reg_t a2) { - data_t y = pop_data(), - x = pop_data(); - push_data(x / y); + set_local(a0, get_local(a1) / get_local(a2)); } /*! ** Pops two data objects from the data stack and pushes their modulus ** on the data stack. */ -void Spasm::modulus() +void Spasm::modulus(reg_t a0, reg_t a1, reg_t a2) { - data_t y = pop_data(), - x = pop_data(); - push_data(x % y); + set_local(a0, get_local(a1) % get_local(a2)); } /*! @@ -233,13 +257,12 @@ void Spasm::modulus() ** If the data_t object on top of the data stack evaluates to true ** execution continues from the place pointed by number in the next bytes */ -void Spasm::gotrue() +void Spasm::gotrue(reg_t a0, reg_t a1) { - ++pc; - if (pop_data()) - pc = *(reinterpret_cast<PC_t*>(bytecode + pc)) - 1; - else - pc += sizeof(size_t) - 1; + if (get_local(a0)) + { + m_PC = a1; + } } /*! @@ -247,23 +270,21 @@ void Spasm::gotrue() ** If the data_t object on top of the data stack evaluates to false ** execution continues from the place pointed by number in the next bytes */ -void Spasm::gofalse() +void Spasm::gofalse(reg_t a0, reg_t a1) { - ++pc; - if (!pop_data()) - pc = *(reinterpret_cast<PC_t*>(bytecode + pc)) - 1; - else - pc += sizeof(size_t) - 1; + if (!get_local(a0)) + { + m_PC = a1; + } } /*! ** Unconditional execution. ** Execution continues from the opcode pointed by the next bytes */ -void Spasm::go() +void Spasm::go(reg_t a0) { - ++pc; - pc = *(reinterpret_cast<PC_t*>(bytecode + pc)) - 1; + m_PC = a0; } /*! @@ -287,11 +308,15 @@ void Spasm::call() ** Function return. The frame of the current function is destroyed and the ** saved return address is loaded in the pc */ -void Spasm::ret() +void Spasm::ret(reg_t reg) { + // TODO: Implement + (void)reg; +#if 0 pc = return_stack.top(); return_stack.pop(); frame.pop_frame(); +#endif } /*! @@ -315,24 +340,32 @@ void Spasm::store() ** Compares the values on top of the stack. Pushes 1 if the value before ** the top of the stack is less than that on top of the stack. */ -void Spasm::less() +void Spasm::less(reg_t a0, reg_t a1, reg_t a2) { - data_t y = pop_data(); - data_t x = pop_data(); - - push_data(x < y); + set_local(a0, get_local(a1) < get_local(a2)); } /*! ** Compares the values on top of the stack. Pushes 1 if the value before ** the top of the stack is less than or equal to that on top of the stack. */ -void Spasm::lesseq() +void Spasm::lesseq(reg_t a0, reg_t a1, reg_t a2) { - data_t y = pop_data(); - data_t x = pop_data(); + set_local(a0, get_local(a1) <= get_local(a2)); +} - push_data(x <= y); +data_t Spasm::get_local(reg_t reg) +{ + assert(&data_stack[0] <= (m_FP + reg)); + assert((m_FP + reg) < &data_stack[data_stack.size() - 1]); + return m_FP[reg]; +} + +void Spasm::set_local(reg_t reg, data_t data) +{ + assert(&data_stack[0] <= (m_FP + reg)); + assert((m_FP + reg) < &data_stack[data_stack.size() - 1]); + m_FP[reg] = data; } data_t Spasm::pop_data() @@ -344,7 +377,14 @@ data_t Spasm::pop_data() void Spasm::push_data(data_t data) { - data_stack.push_back(data); + assert(m_SP < &data_stack[data_stack.size() - 1]); + *(m_SP++) = data; +} + +reg_t Spasm::read_reg(int size) +{ + assert(size == 0); + return m_ByteCode[m_PC++]; } } // namespace SpasmImpl |