.

.idea/ctestState.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project version="4">
+  <component name="CidrCTestProjectState">
+    <ctestState>
+      <lineNumber testId="path:CMakeLists.txt test:tyche_as_test" value="116" />
+      <lineNumber testId="path:CMakeLists.txt test:tyche_bytearray_test" value="102" />
+      <lineNumber testId="path:CMakeLists.txt test:tyche_bytecode_test" value="106" />
+      <lineNumber testId="path:CMakeLists.txt test:tyche_vm_test" value="110" />
+    </ctestState>
+  </component>
+</project>

CMakeLists.txt

@@ -60,32 +60,34 @@ FetchContent_MakeAvailable(googletest)
 
 add_library(lib${PROJECT_NAME} SHARED
         src/common/overloaded.hh
-        src/common/bytearray.hh
-        src/common/bytearray.cc
-        src/bytecode/bytecode.cc
-        src/bytecode/bytecode.hh
-        src/bytecode/bytecodeprototype.hh
-        src/bytecode/constant.hh
-        src/vm/code.cc
-        src/vm/code.hh
-        src/vm/instruction.hh
-        src/vm/instruction.cc
-        src/vm/value.cc
-        src/vm/value.hh
-        src/vm/stack.cc
-        src/vm/stack.hh
-        src/vm/vm_exceptions.hh
-        src/vm/vm.cc
-        src/vm/vm.hh
-        src/vm/expr.cc
-        src/vm/expr.hh
-        src/vm/location.hh
-        src/assembler/lexer.cc
-        src/assembler/lexer.hh
-        src/assembler/assembler.cc
-        src/assembler/assembler.hh
-        src/assembler/as_exceptions.hh
-        src/bytecode/bc_exceptions.hh
+        src/bytearray/bytearray.hh
+        src/bytearray/bytearray.cc
+        src/bytearray/bytearraybuilder.hh
+        src/bytearray/bytearraybuilder.cc
+        #src/bytecode/bytecode.cc
+        #src/bytecode/bytecode.hh
+        #src/bytecode/bytecodeprototype.hh
+        #src/bytecode/constant.hh
+        #src/bytecode/bc_exceptions.hh
+        #src/assembler/lexer.cc
+        #src/assembler/lexer.hh
+        #src/assembler/assembler.cc
+        #src/assembler/assembler.hh
+        #src/assembler/as_exceptions.hh
+        #src/instructions/instruction.hh
+        #src/instructions/instruction.cc
+        #src/vm/code.cc
+        #src/vm/code.hh
+        #src/vm/value.cc
+        #src/vm/value.hh
+        #src/vm/stack.cc
+        #src/vm/stack.hh
+        #src/vm/vm_exceptions.hh
+        #src/vm/vm.cc
+        #src/vm/vm.hh
+        #src/vm/expr.cc
+        #src/vm/expr.hh
+        #src/vm/location.hh
 )
 
 target_compile_options(lib${PROJECT_NAME} PRIVATE ${warnings})
@@ -96,6 +98,10 @@ target_compile_options(lib${PROJECT_NAME} PRIVATE ${warnings})
 
 enable_testing()
 
+add_executable(${PROJECT_NAME}-bytearray-test src/bytearray/tests.cc)
+target_link_libraries(${PROJECT_NAME}-bytearray-test lib${PROJECT_NAME} gtest_main)
+add_test(NAME tyche_bytearray_test COMMAND ${PROJECT_NAME}-bytearray-test)
+
 add_executable(${PROJECT_NAME}-bytecode-test src/bytecode/tests.cc)
 target_link_libraries(${PROJECT_NAME}-bytecode-test lib${PROJECT_NAME} gtest_main)
 add_test(NAME tyche_bytecode_test COMMAND ${PROJECT_NAME}-bytecode-test)
@@ -104,7 +110,9 @@ add_executable(${PROJECT_NAME}-vm-test src/vm/tests.cc)
 target_link_libraries(${PROJECT_NAME}-vm-test lib${PROJECT_NAME} gtest_main)
 add_test(NAME tyche_vm_test COMMAND ${PROJECT_NAME}-vm-test)
 
-add_executable(${PROJECT_NAME}-as-test src/assembler/tests.cc)
+add_executable(${PROJECT_NAME}-as-test src/assembler/tests.cc
+        src/bytearray/bytearraybuilder.cc
+        src/bytearray/bytearraybuilder.hh)
 target_link_libraries(${PROJECT_NAME}-as-test lib${PROJECT_NAME} gtest_main)
 add_test(NAME tyche_as_test COMMAND ${PROJECT_NAME}-as-test)
 

src/assembler/assembler.cc

@@ -4,13 +4,13 @@
 
 #include "as_exceptions.hh"
 #include "../bytecode/bytecode.hh"
-#include "../vm/instruction.hh"
+#include "../instructions/instruction.hh"
 
 using namespace std::string_literals;
 
 namespace tyche::as {
 
-ByteArray Assembler::assemble()
+StaticByteArray Assembler::assemble()
 {
     bc::BytecodePrototype bp;
 
@@ -61,16 +61,16 @@ ByteArray Assembler::assemble()
                 tt = lexer_.ingest();
             }
 
-            auto oinst = vm::translate_instruction(instruction, oper);
+            auto oinst = translate_instruction(instruction, oper);
             if (!oinst)
                 throw AssemblyError("Invalid or misused instruction '" + instruction + "'", tt.line, tt.column);
 
             bp.functions.at(function_id).code.append_byte((uint8_t) *oinst);
-            switch (vm::instruction_operand_type(*oinst)) {
-                case vm::OperandType::Int8:  bp.functions.at(function_id).code.append_int8((int8_t) *oper); break;
-                case vm::OperandType::Int16: bp.functions.at(function_id).code.append_int16((int16_t) *oper); break;
-                case vm::OperandType::Int32: bp.functions.at(function_id).code.append_int32(*oper); break;
-                case vm::OperandType::NoOperand: default: break;
+            switch (instruction_operand_type(*oinst)) {
+                case OperandType::Int8:  bp.functions.at(function_id).code.append_int8((int8_t) *oper); break;
+                case OperandType::Int16: bp.functions.at(function_id).code.append_int16((int16_t) *oper); break;
+                case OperandType::Int32: bp.functions.at(function_id).code.append_int32(*oper); break;
+                case OperandType::NoOperand: default: break;
             }
 
             if (tt.type != TokenType::Enter)

src/assembler/assembler.hh

@@ -5,7 +5,7 @@
 #include <string>
 
 #include "lexer.hh"
-#include "../common/bytearray.hh"
+#include "../bytearray/bytearray.hh"
 #include "../bytecode/bytecodeprototype.hh"
 
 namespace tyche::as {
@@ -14,7 +14,7 @@ class Assembler {
 public:
     explicit Assembler(std::string source) : lexer_(std::move(source) + "\n") {}
 
-    [[nodiscard]] ByteArray assemble();
+    [[nodiscard]] StaticByteArray assemble();
 
 private:
     Lexer lexer_;

src/assembler/lexer.cc

@@ -1,5 +1,8 @@
 #include "lexer.hh"
 
+#include <iostream>
+using namespace std::string_literals;
+
 #include "as_exceptions.hh"
 
 namespace tyche::as {
@@ -119,4 +122,21 @@ void Lexer::ingest_next_token()
     current_token_ = { .type = type, .token = value, .line = current_line, .column = pos_ - current_line_pos };
 }
 
+std::ostream& operator<<(std::ostream& os, Token const& t)
+{
+    switch (t.type) {
+        case TokenType::BOF:         os << "BOF"s; break;
+        case TokenType::Directive:   os << "Directive ("s << std::get<std::string>(t.token) << ")"s;
+        case TokenType::Instruction: os << "Instruction ("s << std::get<std::string>(t.token) << ")"s;
+        case TokenType::Integer:     os << "Integer ("s << std::to_string(std::get<int>(t.token)) << ")"s;
+        case TokenType::Float:       os << "Float ("s << std::to_string(std::get<float>(t.token)) << ")"s;
+        case TokenType::String:      os << "String ("s << std::get<std::string>(t.token) << ")"s;
+        case TokenType::Enter:       os << "Enter"s;
+        case TokenType::Colon:       os << "Colon"s;
+        case TokenType::EOF_:        os << "EOF"s;
+        default:                     os << "???"s;
+    }
+    return os;
+}
+
 } // tyche

src/assembler/lexer.hh

@@ -13,6 +13,7 @@ enum class TokenType {
 
 using TokenValue = std::variant<std::monostate, int, float, std::string>;
 
+
 struct Token {
     TokenType   type;
     TokenValue  token = std::monostate();
@@ -21,6 +22,7 @@ struct Token {
 
     friend bool operator==(Token const& lhs, Token const& rhs) { return std::tie(lhs.type, lhs.token) == std::tie(rhs.type, rhs.token); }
 };
+std::ostream& operator<<(std::ostream& os, Token const& t);
 
 std::string token_type_name(TokenType type);
 

src/assembler/tests.cc

@@ -3,12 +3,11 @@
 
 #include "../bytecode/bytecodeprototype.hh"
 #include "../bytecode/bytecode.hh"
-#include "../vm/instruction.hh"
+#include "../instructions/instruction.hh"
 
 using namespace tyche;
 using namespace tyche::as;
 using namespace tyche::bc;
-using namespace tyche::vm;
 
 TEST(Lexer, Lexer)
 {
@@ -48,7 +47,7 @@ TEST(Assember, Assembler)
     bp.functions.at(1).code.append_byte((uint8_t) Instruction::PushInt16);
     bp.functions.at(1).code.append_int16(5000);
     bp.functions.at(1).code.append_byte((uint8_t) Instruction::Return);
-    ByteArray expected = Bytecode::generate(bp);
+    StaticByteArray expected = Bytecode::generate(bp);
 
     std::string src = R"(
 .const
@@ -65,7 +64,7 @@ TEST(Assember, Assembler)
     ret
 )";
 
-    ByteArray actual = Assembler(src).assemble();
+    StaticByteArray actual = Assembler(src).assemble();
     ASSERT_EQ(expected, actual);
 }
 

src/bytearray/bytearray.cc

@@ -0,0 +1,81 @@
+#include "bytearray.hh"
+
+#include <cstring>
+#include <cstdio>
+
+namespace tyche {
+
+uint8_t StaticByteArray::get_byte(uint32_t addr) const
+{
+    return data_.at(addr);
+}
+
+uint16_t StaticByteArray::get_uint16(uint32_t addr) const
+{
+    return (uint32_t) get_byte(addr)
+            | (uint32_t) get_byte(addr+1) << 8;
+}
+
+uint32_t StaticByteArray::get_uint32(uint32_t addr) const
+{
+    return (uint32_t) get_byte(addr)
+            | (uint32_t) get_byte(addr+1) << 8
+            | (uint32_t) get_byte(addr+2) << 16
+            | (uint32_t) get_byte(addr+3) << 24;
+}
+
+int8_t StaticByteArray::get_int8(uint32_t addr) const
+{
+    return std::bit_cast<int8_t>(get_byte(addr));
+}
+
+int16_t StaticByteArray::get_int16(uint32_t addr) const
+{
+    return (uint16_t) get_byte(addr)
+            | (uint16_t) get_byte(addr+1) << 8;
+}
+
+int32_t StaticByteArray::get_int32(uint32_t addr) const
+{
+    return std::bit_cast<int32_t>((uint32_t) get_byte(addr)
+            | (uint32_t) get_byte(addr+1) << 8
+            | (uint32_t) get_byte(addr+2) << 16
+            | (uint32_t) get_byte(addr+3) << 24);
+}
+
+float StaticByteArray::get_float(uint32_t addr) const
+{
+    uint32_t bits = (uint32_t) get_byte(addr)
+            | (uint32_t) get_byte(addr+1) << 8
+            | (uint32_t) get_byte(addr+2) << 16
+            | (uint32_t) get_byte(addr+3) << 24;
+    float value;
+    std::memcpy(&value, &bits, 4);
+    return value;
+}
+
+std::pair<const char*, size_t> StaticByteArray::get_string_ptr(uint32_t addr) const
+{
+    return { (const char *) &data_.at(addr), strlen((const char *) &data_.at(addr)) + 1 };
+}
+
+std::string StaticByteArray::hexdump() const
+{
+    auto to_hex = [](uint32_t value, size_t n_chars) -> std::string {
+        char buf[15];
+        snprintf(buf, sizeof buf, "%0*X", (int) n_chars, value);
+        return { buf };
+    };
+
+    std::string out;
+    for (size_t i = 0; i < data_.size(); ++i) {
+        if (i % 16 == 0)
+            out += to_hex(i, 4) + " | ";
+        out += to_hex(data_.at(i), 2) + " ";
+        if (i % 16 == 15)
+            out += "\n";
+    }
+    return out + "\n";
+}
+
+}

src/bytearray/bytearray.hh

@@ -0,0 +1,44 @@
+#ifndef TYCHE_BYTEARRAY_HH
+#define TYCHE_BYTEARRAY_HH
+
+#include <cstdint>
+#include <stdexcept>
+#include <string>
+#include <vector>
+
+namespace tyche {
+
+class StaticByteArray {
+public:
+    explicit StaticByteArray(std::vector<uint8_t> const& data) : data_(data) {}
+
+    explicit StaticByteArray(StaticByteArray const& ba) : data_(ba.data()) {}
+
+    // not assignable or moveable
+    StaticByteArray(StaticByteArray&&) = delete;
+    StaticByteArray& operator=(StaticByteArray const&) = delete;
+    StaticByteArray& operator=(StaticByteArray&&) = delete;
+
+    [[nodiscard]] uint8_t                        get_byte(uint32_t addr) const;
+    [[nodiscard]] uint16_t                       get_uint16(uint32_t addr) const;
+    [[nodiscard]] uint32_t                       get_uint32(uint32_t addr) const;
+    [[nodiscard]] int8_t                         get_int8(uint32_t addr) const;
+    [[nodiscard]] int16_t                        get_int16(uint32_t addr) const;
+    [[nodiscard]] int32_t                        get_int32(uint32_t addr) const;
+    [[nodiscard]] float                          get_float(uint32_t addr) const;
+    [[nodiscard]] std::pair<const char*, size_t> get_string_ptr(uint32_t addr) const;
+
+    [[nodiscard]] std::vector<uint8_t> const& data() const { return data_; }
+    [[nodiscard]] size_t size() const { return data_.size(); }
+
+    [[nodiscard]] std::string hexdump() const;
+
+    friend bool operator==(StaticByteArray const& lhs, StaticByteArray const& rhs) { return lhs.data_ == rhs.data_; }
+
+private:
+    const std::vector<uint8_t> data_ {};
+};
+
+}
+
+#endif //TYCHE_BYTEARRAY_HH

src/bytearray/bytearraybuilder.cc

@@ -0,0 +1,88 @@
+#include "bytearraybuilder.hh"
+
+namespace tyche {
+
+ByteArrayBuilder& ByteArrayBuilder::set_byte(uint32_t addr, uint8_t byte)
+{
+    if (data_.size() < (addr + 1))
+        data_.resize(addr + 1, 0);
+    data_.at(addr) = byte;
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_int8(uint32_t addr, int8_t value)
+{
+    set_byte(addr, (uint8_t) value);
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_int16(uint32_t addr, int16_t value)
+{
+    set_byte(addr, (uint8_t) (value));
+    set_byte(addr+1, (uint8_t) (value >> 8));
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_int32(uint32_t addr, int32_t value)
+{
+    set_byte(addr, (uint8_t) (value));
+    set_byte(addr+1, (uint8_t) (value >> 8));
+    set_byte(addr+2, (uint8_t) (value >> 16));
+    set_byte(addr+3, (uint8_t) (value >> 24));
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_uint16(uint32_t addr, uint16_t value)
+{
+    set_byte(addr, (uint8_t) (value));
+    set_byte(addr+1, (uint8_t) (value >> 8));
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_uint32(uint32_t addr, uint32_t value)
+{
+    set_byte(addr, (uint8_t) (value));
+    set_byte(addr+1, (uint8_t) (value >> 8));
+    set_byte(addr+2, (uint8_t) (value >> 16));
+    set_byte(addr+3, (uint8_t) (value >> 24));
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_float(uint32_t addr, float value)
+{
+    uint32_t bits;
+    std::memcpy(&bits, &value, 4);
+    set_byte(addr, (uint8_t) (bits));
+    set_byte(addr+1, (uint8_t) (bits >> 8));
+    set_byte(addr+2, (uint8_t) (bits >> 16));
+    set_byte(addr+3, (uint8_t) (bits >> 24));
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_string(uint32_t addr, std::string const& str)
+{
+    for (uint8_t c: str)
+        set_byte(addr++, c);
+    set_byte(addr, 0);
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::set_bytearray(uint32_t addr, ByteArrayBuilder const& bytearray)
+{
+    for (uint8_t byte: bytearray.data_)
+        set_byte(addr++, byte);
+    return *this;
+}
+
+ByteArrayBuilder& ByteArrayBuilder::append_bytearray(ByteArrayBuilder const& bytearray)
+{
+    data_.insert(data_.end(), bytearray.data_.begin(), bytearray.data_.end());
+    return *this;
+}
+
+StaticByteArray ByteArrayBuilder::build() const
+{
+    return StaticByteArray(data_);
+}
+
+}

src/bytearray/bytearraybuilder.hh

@@ -0,0 +1,45 @@
+#ifndef TYCHE_BYTEARRAYBUILDER_HH
+#define TYCHE_BYTEARRAYBUILDER_HH
+
+#include <cstdint>
+#include <string>
+#include <vector>
+
+#include "bytearray.hh"
+
+namespace tyche {
+
+class ByteArrayBuilder {
+public:
+    ByteArrayBuilder& set_byte(uint32_t addr, uint8_t byte);
+    ByteArrayBuilder& set_uint16(uint32_t addr, uint16_t value);
+    ByteArrayBuilder& set_uint32(uint32_t addr, uint32_t value);
+    ByteArrayBuilder& set_int8(uint32_t addr, int8_t value);
+    ByteArrayBuilder& set_int16(uint32_t addr, int16_t value);
+    ByteArrayBuilder& set_int32(uint32_t addr, int32_t value);
+    ByteArrayBuilder& set_float(uint32_t addr, float value);
+    ByteArrayBuilder& set_string(uint32_t addr, std::string const& str);
+    ByteArrayBuilder& set_bytearray(uint32_t addr, ByteArrayBuilder const& bytearray);
+
+    ByteArrayBuilder& append_byte(uint8_t byte)              { set_byte(data_.size(), byte); return *this; }
+    ByteArrayBuilder& append_uint16(uint16_t value)          { set_uint16(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_uint32(uint32_t value)          { set_uint32(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_int8(int8_t value)              { set_int8(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_int16(int16_t value)            { set_int16(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_int32(int32_t value)            { set_int32(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_float(float value)              { set_float(data_.size(), value); return *this; }
+    ByteArrayBuilder& append_string(std::string const& str)  { set_string(data_.size(), str); return *this; }
+    ByteArrayBuilder& append_bytearray(ByteArrayBuilder const& bytearray);
+
+    [[nodiscard]] std::vector<uint8_t> const& data() const { return data_; }
+    [[nodiscard]] size_t size() const { return data_.size(); }
+
+    [[nodiscard]] StaticByteArray build() const;
+
+private:
+    std::vector<uint8_t> data_ {};
+};
+
+}
+
+#endif //TYCHE_BYTEARRAYBUILDER_HH

src/bytearray/tests.cc

@@ -0,0 +1,51 @@
+#include "gtest/gtest.h"
+
+#include <cstring>
+#include <functional>
+
+#include "bytearray.hh"
+#include "bytearraybuilder.hh"
+
+using namespace tyche;
+
+TEST(StaticByteArray, StaticByteArray)
+{
+    auto test = [](std::function<void(ByteArrayBuilder&)> const& f, std::vector<uint8_t> const& expected) {
+        ByteArrayBuilder ba;
+        f(ba);
+        ASSERT_EQ(ba.data().size(), expected.size());
+        ASSERT_EQ(std::memcmp(ba.data().data(), expected.data(), ba.data().size()), 0);
+    };
+
+#define TESTX(a, ...) test([](ByteArrayBuilder& ba) { a; }, std::vector<uint8_t>({ __VA_ARGS__ }));
+
+    TESTX(ba.set_byte(1, 0xab), 0x00, 0xab)
+
+    ByteArrayBuilder ba;
+    { auto b = ba.set_byte(1, 0xab).build(); ASSERT_EQ(b.get_byte(1), 0xab); }
+
+    { auto b = ba.set_int8(1, 12).build(); ASSERT_EQ(b.get_int8(1), 12); }
+    { auto b = ba.set_int8(1, -12).build(); ASSERT_EQ(b.get_int8(1), -12); }
+    { auto b = ba.set_int16(1, 5000).build(); ASSERT_EQ(b.get_int16(1), 5000); }
+    { auto b = ba.set_int32(1, 5000300).build(); ASSERT_EQ(b.get_int32(1), 5000300); }
+    { auto b = ba.set_int32(1, -5000300).build(); ASSERT_EQ(b.get_int32(1), -5000300); }
+
+    { auto b = ba.set_float(1, 3.14).build(); ASSERT_FLOAT_EQ(b.get_float(1), 3.14); }
+    { auto b = ba.set_float(1, -3.14).build(); ASSERT_FLOAT_EQ(b.get_float(1), -3.14); }
+    { auto b = ba.set_float(1, -5000300.1324).build(); ASSERT_FLOAT_EQ(b.get_float(1), -5000300.1324); }
+
+    {
+        auto b = ba.set_string(1, "Hello world!").build();
+        auto str = b.get_string_ptr(1);
+        EXPECT_STREQ(str.first, "Hello world!");
+        ASSERT_EQ(str.second, 13);
+    }
+
+#undef TESTX
+}
+
+int main(int argc, char** argv)
+{
+    testing::InitGoogleTest(&argc, argv);
+    return RUN_ALL_TESTS();
+}

src/bytecode/bytecode.cc

@@ -5,29 +5,29 @@
 
 namespace tyche::bc {
 
-Bytecode::Bytecode(ByteArray ba)
-    : byte_array_(std::move(ba))
+Bytecode::Bytecode(StaticByteArray const* ba)
+    : byte_array_(ba)
 {
     // check file size
-    if (byte_array_.size() < (TOC_START + TOC_SZ))
+    if (byte_array_->size() < (TOC_START + TOC_SZ))
         throw BytecodeParsingError("Invalid bytecode format (file too short)");
 
     // check magic number and version
-    if (byte_array_.get_uint32(0) != MAGIC_NUMBER)
+    if (byte_array_->get_uint32(0) != MAGIC_NUMBER)
         throw BytecodeParsingError("Invalid bytecode format (magic number not matching)");
-    if (byte_array_.get_uint32(4) != BYTECODE_VERSION)
+    if (byte_array_->get_uint32(4) != BYTECODE_VERSION)
         throw BytecodeParsingError("Unexpected bytecode format version");
 
     // load cache
-    cache_.constants_idx_addr = byte_array_.get_uint32(TOC_START);
-    cache_.n_constants = byte_array_.get_uint16(TOC_START + 4);
-    cache_.functions_idx_addr = byte_array_.get_uint32(TOC_START + (1 * TOC_RECORD_SZ));
-    cache_.n_functions = byte_array_.get_uint16(TOC_START + (1 * TOC_RECORD_SZ) + 4);
-    cache_.constants_start_addr = byte_array_.get_uint32(TOC_START + (2 * TOC_RECORD_SZ));
-    uint32_t code_start = byte_array_.get_uint32(TOC_START + (3 * TOC_RECORD_SZ));
+    cache_.constants_idx_addr = byte_array_->get_uint32(TOC_START);
+    cache_.n_constants = byte_array_->get_uint16(TOC_START + 4);
+    cache_.functions_idx_addr = byte_array_->get_uint32(TOC_START + (1 * TOC_RECORD_SZ));
+    cache_.n_functions = byte_array_->get_uint16(TOC_START + (1 * TOC_RECORD_SZ) + 4);
+    cache_.constants_start_addr = byte_array_->get_uint32(TOC_START + (2 * TOC_RECORD_SZ));
+    uint32_t code_start = byte_array_->get_uint32(TOC_START + (3 * TOC_RECORD_SZ));
     for (uint32_t i = 0; i < cache_.n_functions; ++i) {
-        cache_.function_addr.emplace_back(code_start + byte_array_.get_uint32(cache_.functions_idx_addr + (i * FUNCTION_RECORD_SZ)));
-        cache_.function_sz.emplace_back(byte_array_.get_uint32(cache_.functions_idx_addr + (i * FUNCTION_RECORD_SZ) + 8));
+        cache_.function_addr.emplace_back(code_start + byte_array_->get_uint32(cache_.functions_idx_addr + (i * FUNCTION_RECORD_SZ)));
+        cache_.function_sz.emplace_back(byte_array_->get_uint32(cache_.functions_idx_addr + (i * FUNCTION_RECORD_SZ) + 8));
     }
 }
 
@@ -43,12 +43,12 @@ uint32_t Bytecode::n_functions() const
 
 ConstantValue Bytecode::get_constant(uint32_t idx) const
 {
-    uint32_t constant_idx = byte_array_.get_uint32(cache_.constants_idx_addr + (idx * CONST_RECORD_SZ));
-    switch ((ConstantType) byte_array_.get_byte(cache_.constants_start_addr + constant_idx)) {
+    uint32_t constant_idx = byte_array_->get_uint32(cache_.constants_idx_addr + (idx * CONST_RECORD_SZ));
+    switch ((ConstantType) byte_array_->get_byte(cache_.constants_start_addr + constant_idx)) {
         case CONST_TYPE_FLOAT:
-            return byte_array_.get_float(cache_.constants_start_addr + constant_idx + 1);
+            return byte_array_->get_float(cache_.constants_start_addr + constant_idx + 1);
         case CONST_TYPE_STRING:
-            return byte_array_.get_string(cache_.constants_start_addr + constant_idx + 1).first;
+            return byte_array_->get_string_ptr(cache_.constants_start_addr + constant_idx + 1).first;
         default:
             throw BytecodeParsingError("Invalid bytecode format (invalid constant type)");
     }
@@ -58,8 +58,8 @@ Bytecode::FunctionDef Bytecode::get_function_def(uint32_t function_id) const
 {
     uint32_t idx = cache_.functions_idx_addr + (function_id * FUNCTION_RECORD_SZ);
     return {
-        .n_params = byte_array_.get_uint16(idx + 4),
-        .locals = byte_array_.get_uint16(idx + 6),
+        .n_params = byte_array_->get_uint16(idx + 4),
+        .locals = byte_array_->get_uint16(idx + 6),
     };
 }
 
@@ -70,34 +70,34 @@ uint32_t Bytecode::get_function_sz(uint32_t function_id) const
 
 uint8_t Bytecode::get_code_byte(uint32_t function_id, uint32_t idx) const
 {
-    return byte_array_.get_byte(cache_.function_addr.at(function_id) + idx);
+    return byte_array_->get_byte(cache_.function_addr.at(function_id) + idx);
 }
 
 int8_t Bytecode::get_code_int8(uint32_t function_id, uint32_t idx) const
 {
-    return byte_array_.get_int8(cache_.function_addr.at(function_id) + idx);
+    return byte_array_->get_int8(cache_.function_addr.at(function_id) + idx);
 }
 
 int16_t Bytecode::get_code_int16(uint32_t function_id, uint32_t idx) const
 {
-    return byte_array_.get_int16(cache_.function_addr.at(function_id) + idx);
+    return byte_array_->get_int16(cache_.function_addr.at(function_id) + idx);
 }
 
 int32_t Bytecode::get_code_int32(uint32_t function_id, uint32_t idx) const
 {
-    return byte_array_.get_int32(cache_.function_addr.at(function_id) + idx);
+    return byte_array_->get_int32(cache_.function_addr.at(function_id) + idx);
 }
 
-ByteArray Bytecode::generate(BytecodePrototype const& bp)
+StaticByteArray Bytecode::generate(BytecodePrototype const& bp)
 {
     // header section
-    ByteArray header;
+    ByteArrayBuilder header;
     header.set_uint32(0, MAGIC_NUMBER);
     header.set_byte(4, BYTECODE_VERSION);
 
     // constants
-    ByteArray constant_indexes;
-    ByteArray raw_constants;
+    ByteArrayBuilder constant_indexes;
+    ByteArrayBuilder raw_constants;
 
     uint32_t idx = 0;
     for (auto const& constant: bp.constants) {
@@ -116,8 +116,8 @@ ByteArray Bytecode::generate(BytecodePrototype const& bp)
     }
 
     // functions
-    ByteArray functions_indexes;
-    ByteArray raw_code;
+    ByteArrayBuilder functions_indexes;
+    ByteArrayBuilder raw_code;
 
     uint32_t idx_idx = 0, code_idx = 0;
     for (auto const& f: bp.functions) {
@@ -135,7 +135,7 @@ ByteArray Bytecode::generate(BytecodePrototype const& bp)
     uint32_t raw_constant_start = function_idx_start + functions_indexes.size();
     uint32_t raw_code_start = raw_constant_start + raw_constants.size();
 
-    ByteArray toc;
+    ByteArrayBuilder toc;
     if (!bp.constants.empty()) {
         toc.set_uint32(SEC_CONST_IDX * TOC_RECORD_SZ, CONST_IDX_START);
         toc.set_uint32(SEC_CONST_IDX * TOC_RECORD_SZ + 4, constant_indexes.size() / CONST_RECORD_SZ);
@@ -153,14 +153,14 @@ ByteArray Bytecode::generate(BytecodePrototype const& bp)
     // assemble bytecode
     //
 
-    ByteArray ba;
+    ByteArrayBuilder ba;
     ba.set_bytearray(0, header);
     ba.set_bytearray(TOC_START, toc);
     ba.set_bytearray(CONST_IDX_START, constant_indexes);
     ba.set_bytearray(function_idx_start, functions_indexes);
     ba.set_bytearray(raw_constant_start, raw_constants);
     ba.set_bytearray(raw_code_start, raw_code);
-    return ba;
+    return ba.build();
 }
 
 }

src/bytecode/bytecode.hh

@@ -1,15 +1,15 @@
 #ifndef TYCHE_BYTECODE_HH
 #define TYCHE_BYTECODE_HH
 
-#include "../common/bytearray.hh"
+#include "../bytearray/bytearray.hh"
 #include "bytecodeprototype.hh"
+#include "constant.hh"
 
 namespace tyche::bc {
 
 class Bytecode {
 public:
-    Bytecode() = default;
-    explicit Bytecode(ByteArray ba);
+    explicit Bytecode(StaticByteArray const* ba);
 
     [[nodiscard]] uint32_t n_constants() const;
     [[nodiscard]] uint32_t n_functions() const;
@@ -27,10 +27,10 @@ public:
 
     // TODO - debugging info
 
-    [[nodiscard]] static ByteArray generate(BytecodePrototype const& bp);
+    [[nodiscard]] static StaticByteArray generate(BytecodePrototype const& bp);
 
 private:
-    ByteArray byte_array_;      // the actual data
+    StaticByteArray const* byte_array_;      // the actual data
 
     static constexpr uint8_t  BYTECODE_VERSION = 1;
     static constexpr uint32_t MAGIC_NUMBER = 0x74b3c138;

src/bytecode/bytecodeprototype.hh

@@ -5,8 +5,7 @@
 #include <string>
 #include <variant>
 #include <vector>
-#include "constant.hh"
-#include "../common/bytearray.hh"
+#include "../bytearray/bytearraybuilder.hh"
 
 namespace tyche::bc {
 
@@ -14,11 +13,12 @@ struct BytecodePrototype {
     struct Function {
         uint16_t         n_pars;
         uint16_t         n_locals;
-        ByteArray code {};
+        ByteArrayBuilder code {};
 
-        Function(uint16_t n_pars_, uint16_t n_locals_) : n_pars(n_pars_), n_locals(n_locals_), code(ByteArray {}) {}
+        Function(uint16_t n_pars_, uint16_t n_locals_) : n_pars(n_pars_), n_locals(n_locals_), code(ByteArrayBuilder {}) {}
     };
 
+    using ConstantValue = std::variant<float, std::string>;
     std::vector<ConstantValue> constants {};
     std::vector<Function> functions {};
 

src/bytecode/constant.hh

@@ -6,7 +6,7 @@
 
 namespace tyche::bc {
 
-using ConstantValue = std::variant<float, std::string>;
+using ConstantValue = std::variant<float, const char*>;
 
 enum ConstantType : uint8_t { CONST_TYPE_FLOAT = 1, CONST_TYPE_STRING = 2 };
 

src/bytecode/tests.cc

@@ -3,40 +3,46 @@
 #include <cstring>
 #include <functional>
 
-#include "../common/bytearray.hh"
+#include "../bytearray/bytearray.hh"
+#include "../bytearray/bytearraybuilder.hh"
 #include "bytecodeprototype.hh"
 #include "bytecode.hh"
 
 using namespace tyche;
 using namespace tyche::bc;
 
-TEST(ByteArray, ByteArray)
+TEST(StaticByteArray, StaticByteArray)
 {
-    auto test = [](std::function<void(ByteArray&)> const& f, std::vector<uint8_t> const& expected) {
-        ByteArray ba;
+    auto test = [](std::function<void(ByteArrayBuilder&)> const& f, std::vector<uint8_t> const& expected) {
+        ByteArrayBuilder ba;
         f(ba);
         ASSERT_EQ(ba.data().size(), expected.size());
         ASSERT_EQ(std::memcmp(ba.data().data(), expected.data(), ba.data().size()), 0);
     };
 
-#define TESTX(a, ...) test([](ByteArray& ba) { a; }, std::vector<uint8_t>({ __VA_ARGS__ }));
+#define TESTX(a, ...) test([](ByteArrayBuilder& ba) { a; }, std::vector<uint8_t>({ __VA_ARGS__ }));
 
     TESTX(ba.set_byte(1, 0xab), 0x00, 0xab)
 
-    ByteArray ba;
-    ba.set_byte(1, 0xab); ASSERT_EQ(ba.get_byte(1), 0xab);
+    ByteArrayBuilder ba;
+    { auto b = ba.set_byte(1, 0xab).build(); ASSERT_EQ(b.get_byte(1), 0xab); }
 
-    ba.set_int8(1, 12); ASSERT_EQ(ba.get_int8(1), 12);
-    ba.set_int8(1, -12); ASSERT_EQ(ba.get_int8(1), -12);
-    ba.set_int16(1, 5000); ASSERT_EQ(ba.get_int16(1), 5000);
-    ba.set_int32(1, 5000300); ASSERT_EQ(ba.get_int32(1), 5000300);
-    ba.set_int32(1, -5000300); ASSERT_EQ(ba.get_int32(1), -5000300);
+    { auto b = ba.set_int8(1, 12).build(); ASSERT_EQ(b.get_int8(1), 12); }
+    { auto b = ba.set_int8(1, -12).build(); ASSERT_EQ(b.get_int8(1), -12); }
+    { auto b = ba.set_int16(1, 5000).build(); ASSERT_EQ(b.get_int16(1), 5000); }
+    { auto b = ba.set_int32(1, 5000300).build(); ASSERT_EQ(b.get_int32(1), 5000300); }
+    { auto b = ba.set_int32(1, -5000300).build(); ASSERT_EQ(b.get_int32(1), -5000300); }
 
-    ba.set_float(1, 3.14); ASSERT_FLOAT_EQ(ba.get_float(1), 3.14);
-    ba.set_float(1, -3.14); ASSERT_FLOAT_EQ(ba.get_float(1), -3.14);
-    ba.set_float(1, -5000300.1324); ASSERT_FLOAT_EQ(ba.get_float(1), -5000300.1324);
+    { auto b = ba.set_float(1, 3.14).build(); ASSERT_FLOAT_EQ(b.get_float(1), 3.14); }
+    { auto b = ba.set_float(1, -3.14).build(); ASSERT_FLOAT_EQ(b.get_float(1), -3.14); }
+    { auto b = ba.set_float(1, -5000300.1324).build(); ASSERT_FLOAT_EQ(b.get_float(1), -5000300.1324); }
 
-    ba.set_string(1, "Hello world!"); ASSERT_EQ(ba.get_string(1), std::make_pair("Hello world!", 13));
+    {
+        auto b = ba.set_string(1, "Hello world!").build();
+        auto str = b.get_string_ptr(1);
+        EXPECT_STREQ(str.first, "Hello world!");
+        ASSERT_EQ(str.second, 13);
+    }
 
 #undef TESTX
 }
@@ -73,7 +79,7 @@ TEST(Bytecode, Constants)
             CONST_TYPE_STRING, 'H', 'E', 'L', 'L', 'O', 0x00
     };
 
-    ByteArray ba = Bytecode::generate(bp);
+    StaticByteArray ba = Bytecode::generate(bp);
     ASSERT_EQ(ba.data(), expected);
 }
 
@@ -112,7 +118,7 @@ TEST(Bytecode, Code)
             0x68, 42, 0x42,
     };
 
-    ByteArray ba = Bytecode::generate(bp);
+    StaticByteArray ba = Bytecode::generate(bp);
     ASSERT_EQ(ba.data(), expected);
 }
 
@@ -132,12 +138,12 @@ TEST(Bytecode, Parsing)
     auto& ff = bp.functions.emplace_back(2, 1);
     ff.code.append_byte(0x42);
 
-    ByteArray ba = Bytecode::generate(bp);
+    StaticByteArray ba = Bytecode::generate(bp);
     // print(ba.data());
 
     // read bytecode
 
-    Bytecode bc(std::move(ba));
+    Bytecode bc(&ba);
 
     ASSERT_EQ(bc.n_constants(), 2);
     ASSERT_EQ(bc.n_functions(), 2);
@@ -145,7 +151,7 @@ TEST(Bytecode, Parsing)
     ASSERT_EQ(bc.get_function_sz(1), 1);
 
     ASSERT_FLOAT_EQ(std::get<float>(bc.get_constant(0)), 3.14f);
-    ASSERT_EQ(std::get<std::string>(bc.get_constant(1)), "HELLO");
+    EXPECT_STREQ(std::get<const char*>(bc.get_constant(1)), "HELLO");
 
     Bytecode::FunctionDef f1 = bc.get_function_def(0);
     ASSERT_EQ(f1.n_params, 0);

src/common/bytearray.cc

@@ -1,152 +0,0 @@
-#include "bytearray.hh"
-
-#include <cstring>
-#include <cstdio>
-
-namespace tyche {
-
-void ByteArray::set_byte(uint32_t addr, uint8_t byte)
-{
-    if (data_.size() < (addr + 1))
-        data_.resize(addr + 1, 0);
-    data_.at(addr) = byte;
-}
-
-void ByteArray::set_int8(uint32_t addr, int8_t value)
-{
-    set_byte(addr, (uint8_t) value);
-}
-
-void ByteArray::set_int16(uint32_t addr, int16_t value)
-{
-    set_byte(addr, (uint8_t) (value));
-    set_byte(addr+1, (uint8_t) (value >> 8));
-}
-
-void ByteArray::set_int32(uint32_t addr, int32_t value)
-{
-    set_byte(addr, (uint8_t) (value));
-    set_byte(addr+1, (uint8_t) (value >> 8));
-    set_byte(addr+2, (uint8_t) (value >> 16));
-    set_byte(addr+3, (uint8_t) (value >> 24));
-}
-
-void ByteArray::set_uint16(uint32_t addr, uint16_t value)
-{
-    set_byte(addr, (uint8_t) (value));
-    set_byte(addr+1, (uint8_t) (value >> 8));
-}
-
-void ByteArray::set_uint32(uint32_t addr, uint32_t value)
-{
-    set_byte(addr, (uint8_t) (value));
-    set_byte(addr+1, (uint8_t) (value >> 8));
-    set_byte(addr+2, (uint8_t) (value >> 16));
-    set_byte(addr+3, (uint8_t) (value >> 24));
-}
-
-void ByteArray::set_float(uint32_t addr, float value)
-{
-    uint32_t bits;
-    std::memcpy(&bits, &value, 4);
-    set_byte(addr, (uint8_t) (bits));
-    set_byte(addr+1, (uint8_t) (bits >> 8));
-    set_byte(addr+2, (uint8_t) (bits >> 16));
-    set_byte(addr+3, (uint8_t) (bits >> 24));
-}
-
-void ByteArray::set_string(uint32_t addr, std::string const& str)
-{
-    for (uint8_t c: str)
-        set_byte(addr++, c);
-    set_byte(addr, 0);
-}
-
-void ByteArray::set_bytearray(uint32_t addr, ByteArray const& bytearray)
-{
-    for (uint8_t byte: bytearray.data())
-        set_byte(addr++, byte);
-}
-
-uint8_t ByteArray::get_byte(uint32_t addr) const
-{
-    return data_.at(addr);
-}
-
-uint16_t ByteArray::get_uint16(uint32_t addr) const
-{
-    return (uint32_t) get_byte(addr)
-            | (uint32_t) get_byte(addr+1) << 8;
-}
-
-uint32_t ByteArray::get_uint32(uint32_t addr) const
-{
-    return (uint32_t) get_byte(addr)
-            | (uint32_t) get_byte(addr+1) << 8
-            | (uint32_t) get_byte(addr+2) << 16
-            | (uint32_t) get_byte(addr+3) << 24;
-}
-
-int8_t ByteArray::get_int8(uint32_t addr) const
-{
-    return std::bit_cast<int8_t>(get_byte(addr));
-}
-
-int16_t ByteArray::get_int16(uint32_t addr) const
-{
-    return (uint16_t) get_byte(addr)
-            | (uint16_t) get_byte(addr+1) << 8;
-}
-
-int32_t ByteArray::get_int32(uint32_t addr) const
-{
-    return std::bit_cast<int32_t>((uint32_t) get_byte(addr)
-            | (uint32_t) get_byte(addr+1) << 8
-            | (uint32_t) get_byte(addr+2) << 16
-            | (uint32_t) get_byte(addr+3) << 24);
-}
-
-float ByteArray::get_float(uint32_t addr) const
-{
-    uint32_t bits = (uint32_t) get_byte(addr)
-            | (uint32_t) get_byte(addr+1) << 8
-            | (uint32_t) get_byte(addr+2) << 16
-            | (uint32_t) get_byte(addr+3) << 24;
-    float value;
-    std::memcpy(&value, &bits, 4);
-    return value;
-}
-
-std::pair<std::string, size_t> ByteArray::get_string(uint32_t addr) const
-{
-    std::string data;
-    while (char c = (char) get_byte(addr++))
-        data += c;
-    return { data, data.size() + 1 };
-}
-
-void ByteArray::append_bytearray(ByteArray const& bytearray)
-{
-    data_.insert(data_.end(), bytearray.data().begin(), bytearray.data().end());
-}
-
-std::string ByteArray::hexdump() const
-{
-    auto to_hex = [](uint32_t value, size_t n_chars) -> std::string {
-        char buf[15];
-        snprintf(buf, sizeof buf, "%0*X", (int) n_chars, value);
-        return { buf };
-    };
-
-    std::string out;
-    for (size_t i = 0; i < data_.size(); ++i) {
-        if (i % 16 == 0)
-            out += to_hex(i, 4) + " | ";
-        out += to_hex(data_.at(i), 2) + " ";
-        if (i % 16 == 15)
-            out += "\n";
-    }
-    return out + "\n";
-}
-
-}

src/common/bytearray.hh

@@ -1,58 +0,0 @@
-#ifndef TYCHE_BYTEARRAY_HH
-#define TYCHE_BYTEARRAY_HH
-
-#include <cstdint>
-#include <stdexcept>
-#include <string>
-#include <vector>
-
-namespace tyche {
-
-class ByteArray {
-public:
-    ByteArray() = default;
-    explicit ByteArray(std::vector<uint8_t> data) : data_(std::move(data)) {}
-
-    void set_byte(uint32_t addr, uint8_t byte);
-    void set_uint16(uint32_t addr, uint16_t value);
-    void set_uint32(uint32_t addr, uint32_t value);
-    void set_int8(uint32_t addr, int8_t value);
-    void set_int16(uint32_t addr, int16_t value);
-    void set_int32(uint32_t addr, int32_t value);
-    void set_float(uint32_t addr, float value);
-    void set_string(uint32_t addr, std::string const& str);
-    void set_bytearray(uint32_t addr, ByteArray const& bytearray);
-
-    void append_byte(uint8_t byte)              { set_byte(data_.size(), byte); }
-    void append_uint16(uint16_t value)          { set_uint16(data_.size(), value); }
-    void append_uint32(uint32_t value)          { set_uint32(data_.size(), value); }
-    void append_int8(int8_t value)              { set_int8(data_.size(), value); }
-    void append_int16(int16_t value)            { set_int16(data_.size(), value); }
-    void append_int32(int32_t value)            { set_int32(data_.size(), value); }
-    void append_float(float value)              { set_float(data_.size(), value); }
-    void append_string(std::string const& str)  { set_string(data_.size(), str); }
-    void append_bytearray(ByteArray const& bytearray);
-
-    [[nodiscard]] uint8_t                        get_byte(uint32_t addr) const;
-    [[nodiscard]] uint16_t                       get_uint16(uint32_t addr) const;
-    [[nodiscard]] uint32_t                       get_uint32(uint32_t addr) const;
-    [[nodiscard]] int8_t                         get_int8(uint32_t addr) const;
-    [[nodiscard]] int16_t                        get_int16(uint32_t addr) const;
-    [[nodiscard]] int32_t                        get_int32(uint32_t addr) const;
-    [[nodiscard]] float                          get_float(uint32_t addr) const;
-    [[nodiscard]] std::pair<std::string, size_t> get_string(uint32_t addr) const;
-
-    [[nodiscard]] std::vector<uint8_t> const& data() const { return data_; }
-    [[nodiscard]] size_t size() const { return data_.size(); }
-
-    [[nodiscard]] std::string hexdump() const;
-
-    friend bool operator==(ByteArray const& lhs, ByteArray const& rhs) { return lhs.data_ == rhs.data_; }
-
-private:
-    std::vector<uint8_t> data_ {};
-};
-
-}
-
-#endif //TYCHE_BYTEARRAY_HH

src/instructions/instruction.cc

@@ -3,7 +3,7 @@
 #include <limits>
 #include <unordered_map>
 
-namespace tyche::vm {
+namespace tyche {
 
 const std::unordered_map<std::string, Instruction> instruction_names = {
     { "pushi", Instruction::PushInt8 },

src/instructions/instruction.hh

@@ -8,7 +8,7 @@
 
 #include "../bytecode/bytecode.hh"
 
-namespace tyche::vm {
+namespace tyche {
 
 constexpr uint8_t OPCODE_NEXT_SIZE = 0x20;
 

src/vm/code.cc

@@ -1,12 +1,12 @@
 #include "code.hh"
 #include "../common/overloaded.hh"
-#include "instruction.hh"
+#include "../instructions/instruction.hh"
 
 namespace tyche::vm {
 
-FunctionId Code::import_bytecode(ByteArray incoming)
+FunctionId Code::import_bytecode(StaticByteArray const* incoming)
 {
-    bc::Bytecode bc(std::move(incoming));
+    bc::Bytecode bc(incoming);
     // TODO - adjust function calls, constants
 
     bytecode_ = std::move(bc);

src/vm/code.hh

@@ -1,7 +1,7 @@
 #ifndef TYCHE_CODE_HH
 #define TYCHE_CODE_HH
 
-#include "instruction.hh"
+#include "../instructions/instruction.hh"
 #include "location.hh"
 #include "value.hh"
 #include "../bytecode/bytecode.hh"
@@ -17,7 +17,7 @@ struct Operation
 
 class Code {
 public:
-    FunctionId import_bytecode(ByteArray incoming);
+    FunctionId import_bytecode(StaticByteArray const* incoming);
 
     [[nodiscard]] std::string disassemble() const;
 

src/vm/expr.cc

@@ -35,7 +35,7 @@ static int init_ = []() {
     BIN_OP(Sum, Integer, Float)   { return Value::createFloat((float) a.as_integer() + b.as_float()); };
     BIN_OP(Sum, Float, Integer)   { return Value::createFloat(a.as_float() + (float) b.as_integer()); };
     BIN_OP(Sum, Float, Float)     { return Value::createFloat(a.as_float() + b.as_float()); };
-    BIN_OP(Sum, String, String)   { return Value::createString(a.as_string() + b.as_string()); };
+    BIN_OP(Sum, String, String)   { return Value::createString(std::string(a.as_string_ptr()) + std::string(b.as_string_ptr())); };
 
     BIN_OP(Subtraction, Integer, Integer) { return Value::createInteger(a.as_integer() - b.as_integer()); };
     BIN_OP(Subtraction, Integer, Float)   { return Value::createFloat((float) a.as_integer() - b.as_float()); };
@@ -61,13 +61,13 @@ static int init_ = []() {
     BIN_OP(Equality, Integer, Float)   { return Value::createIntegerFromBool(std::abs((float) a.as_integer() - b.as_float()) < FLOAT_EPSILON); };
     BIN_OP(Equality, Float, Integer)   { return Value::createIntegerFromBool(std::abs(a.as_float() - (float) b.as_integer()) < FLOAT_EPSILON); };
     BIN_OP(Equality, Float, Float)     { return Value::createIntegerFromBool(std::abs(a.as_float() - b.as_float()) < FLOAT_EPSILON); };
-    BIN_OP(Equality, String, String)   { return Value::createIntegerFromBool(a.as_string() == b.as_string()); };
+    BIN_OP(Equality, String, String)   { return Value::createIntegerFromBool(strcmp(a.as_string_ptr(), b.as_string_ptr()) == 0); };
 
     BIN_OP(Inequality, Integer, Integer) { return Value::createIntegerFromBool(a.as_integer() != b.as_integer()); };
     BIN_OP(Inequality, Integer, Float)   { return Value::createIntegerFromBool(std::abs((float) a.as_integer() - b.as_float()) >= FLOAT_EPSILON); };
     BIN_OP(Inequality, Float, Integer)   { return Value::createIntegerFromBool(std::abs(a.as_float() - (float) b.as_integer()) >= FLOAT_EPSILON); };
     BIN_OP(Inequality, Float, Float)     { return Value::createIntegerFromBool(std::abs(a.as_float() - b.as_float()) >= FLOAT_EPSILON); };
-    BIN_OP(Inequality, String, String)   { return Value::createIntegerFromBool(a.as_string() != b.as_string()); };
+    BIN_OP(Inequality, String, String)   { return Value::createIntegerFromBool(strcmp(a.as_string_ptr(), b.as_string_ptr()) != 0); };
 
     BIN_OP(LessThan, Integer, Integer) { return Value::createIntegerFromBool(a.as_integer() < b.as_integer()); };
     BIN_OP(LessThan, Integer, Float)   { return Value::createIntegerFromBool((float) a.as_integer() < b.as_float()); };

src/vm/tests.cc

@@ -110,7 +110,7 @@ TEST(VM, StackOperations)
     ASSERT_FLOAT_EQ(run("pushi 5000").to_float(-1), 5000.f);
     ASSERT_FLOAT_EQ(run("pushc 0").to_float(-1), 3.14f);
     ASSERT_EQ(run("pushc 0").to_integer(-1), 3);
-    ASSERT_EQ(run("pushc 1").to_string(-1), "Hello world");
+    EXPECT_STREQ(run("pushc 1").to_string_ptr(-1), "Hello world");
     ASSERT_TRUE(run("pushf 0").is_function(-1));
     ASSERT_EQ(run("pushi 2\n pushi 3\n pop").to_integer(-1), 2);
 }
@@ -224,7 +224,7 @@ TEST(VM, FloatFloatOperations)
 
 TEST(VM, StringString)
 {
-    ASSERT_EQ(run(R"(
+    EXPECT_STREQ(run(R"(
         .const
             0: "Hello"
             1: "World"
@@ -233,7 +233,7 @@ TEST(VM, StringString)
             pushc 1
             sum
             ret
-    )").to_string(-1), "HelloWorld");
+    )").to_string_ptr(-1), "HelloWorld");
 
     ASSERT_EQ(run(R"(
         .const

src/vm/value.cc

@@ -41,4 +41,13 @@ std::string Value::to_string() const
     }, value_);
 }
 
+const char* Value::as_string_ptr() const
+{
+    if (auto s = std::get_if<std::string>(&value_))
+        return s->c_str();
+    if (auto s = std::get_if<const char*>(&value_))
+        return *s;
+    throw std::logic_error("Shouldn't get here");
+}
+
 }

src/vm/value.hh

@@ -26,6 +26,7 @@ public:
     static Value createInteger(int32_t v) { return Value(v); }
     static Value createFloat(float f) { return Value(f); }
     static Value createString(std::string const& str) { return Value(str); }
+    static Value createStringFromConstant(const char* str) { return Value(str); }
     static Value createFunctionId(FunctionId f_id) { return Value(Function { f_id }); }
 
     static Value createFalse() { return createInteger(0); }
@@ -36,13 +37,13 @@ public:
 
     [[nodiscard]] int32_t     as_integer() const     { return std::get<int32_t>(value_); }
     [[nodiscard]] float       as_float() const       { return std::get<float>(value_); }
-    [[nodiscard]] std::string as_string() const      { return std::get<std::string>(value_); }
+    [[nodiscard]] const char* as_string_ptr() const;
     [[nodiscard]] FunctionId  as_function_id() const { return std::get<Function>(value_).f_id; }
 
     [[nodiscard]] std::string to_string() const;
 
 private:
-    using Internal = std::variant<std::monostate, int32_t, float, std::string, Function>;
+    using Internal = std::variant<std::monostate, int32_t, float, std::string, const char*, Function>;
     Internal value_;
 
     explicit Value(Internal const& internal) : value_(internal) {}

src/vm/vm.cc

@@ -49,11 +49,11 @@ float VM::to_float(int index) const
     throw VMTypeError(Type::Float, f.type());
 }
 
-std::string VM::to_string(int index) const
+const char* VM::to_string_ptr(int index) const
 {
-    Value i = stack_.at(index);
-    assert_type(i, Type::String);
-    return i.as_string();
+    Value s = stack_.at(index);
+    assert_type(s, Type::String);
+    return s.as_string_ptr();
 }
 
 VM& VM::push_nil()
@@ -110,8 +110,8 @@ void VM::step()
             auto cnst = code_.bytecode().get_constant(op.operator_);
             if (auto f = std::get_if<float>(&cnst))
                 push_float(*f);
-            else if (auto s = std::get_if<std::string>(&cnst))
-                push_string(*s);
+            else if (auto s = std::get_if<const char*>(&cnst))
+                stack_.push(Value::createStringFromConstant(*s));
             else
                 throw std::logic_error("Shouldn't get here");
             break;

src/vm/vm.hh

@@ -31,7 +31,7 @@ public:
 
     [[nodiscard]] int32_t     to_integer(int index) const;
     [[nodiscard]] float       to_float(int index) const;
-    [[nodiscard]] std::string to_string(int index) const;
+    [[nodiscard]] const char* to_string_ptr(int index) const;
 
     [[nodiscard]] std::string debug_stack() const { return stack_.debug(); }