test program works

runtime/main.cpp

@@ -63,7 +63,7 @@ auto compile_asm(const std::vector<AsmLine>& lines) -> std::vector<uint32_t>
                 break;
             }
             case AsmLineType::Loc: {
-                locs.insert_or_assign(std::get<Loc>(line.value).value, ip + 1);
+                locs.insert_or_assign(std::get<Loc>(line.value).value, ip);
                 break;
             }
             case AsmLineType::Ref: {
@@ -75,9 +75,15 @@ auto compile_asm(const std::vector<AsmLine>& lines) -> std::vector<uint32_t>
         }
     }
     for (size_t i = 0; i < output.size(); ++i) {
-        if (refs.contains(i)) {
-            output.at(i) = static_cast<uint32_t>(locs.at(refs.at(i)));
+        if (!refs.contains(i)) {
+            continue;
         }
+        if (!locs.contains(refs.at(i))) {
+            std::cerr << std::format(
+                "error: label \"{}\" used at {} not defined\n", refs.at(i), i);
+            continue;
+        }
+        output.at(i) = static_cast<uint32_t>(locs.at(refs.at(i)));
     }
     return output;
 }
@@ -92,19 +98,23 @@ int main()
     //      + a b
     //  }
     //
-    //  let result = 0;
-    //  let i = 0;
-    //  loop {
-    //      if i >= 10 {
-    //          break;
+    //  fn main() {
+    //      let result = 0;
+    //      let i = 0;
+    //      loop {
+    //          if i >= 10 {
+    //              break;
+    //          }
+    //          result = add(result, 5);
+    //          i = + i 1;
     //      }
-    //      result = add(result, 5);
+    //      result
     //  }
     auto program_asm = std::vector<AsmLine> {
         // clang-format off
         SourceMap,  0, 0, 0,
         PushPtr,    R("main"),
-        Pop,
+        Call,       0,
         PushPtr,    R("_exit"),
         Jump,
         Pop,
@@ -112,15 +122,17 @@ int main()
         SourceMap,  19, 2, 5,
         Add,
         Return,
+        L("main"),
         SourceMap,  28, 5, 1,
         PushInt,    0,
+        PushInt,    0,
         SourceMap,  44, 6, 1,
         PushInt,    0,
         SourceMap,  55, 7, 1,
-        L("1"),
+        L("0"),
         SourceMap,  66, 8,  5,
-        LoadLocal,  1,
-        PushInt,    0,
+        LoadLocal,  2,
+        PushInt,    10,
         LessThan,
         Not,
         PushPtr,    R("1"),
@@ -128,22 +140,25 @@ int main()
         SourceMap,  87, 9, 9,
         PushPtr,    R("2"),
         Jump,
+        L("1"),
         SourceMap,  104, 11, 5,
-        LoadLocal,  0,
+        LoadLocal,  1,
         PushInt,    5,
         PushPtr,    R("add"),
         Call,       2,
-        StoreLocal, 0,
+        StoreLocal, 1,
         SourceMap,  133, 12, 5,
-        LoadLocal,  1,
+        LoadLocal,  2,
         PushInt,    1,
         Add,
-        StoreLocal, 1,
+        StoreLocal, 2,
         PushPtr,    R("0"),
         Jump,
         L("2"),
+        LoadLocal,  1,
+        StoreLocal, 0,
+        Pop,
         Pop,
-        PushNull,
         Return,
         L("_exit"),
         SourceMap,  147, 15, 1
@@ -156,6 +171,5 @@ int main()
             .code_coverage = true,
         });
     vm.run_until_done();
-
-    vm.print_stack();
+    std::cout << std::format("done\n{}\n", vm.stack_repr_string());
 }

runtime/value.hpp

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <cstdint>
+#include <cstdlib>
 #include <format>
 #include <iostream>
 #include <string>
@@ -50,6 +51,15 @@ struct Ptr {
     uint32_t value;
 };
 
+// clang-format off
+template <ValueType op> struct ValueTypeToType {  };
+template <> struct ValueTypeToType<ValueType::Null> { using Type = Null; };
+template <> struct ValueTypeToType<ValueType::Int> { using Type = Int; };
+template <> struct ValueTypeToType<ValueType::Bool> { using Type = Bool; };
+template <> struct ValueTypeToType<ValueType::String> { using Type = String; };
+template <> struct ValueTypeToType<ValueType::Ptr> { using Type = Ptr; };
+// clang-format on
+
 class Value {
 public:
     Value(Null&& value)
@@ -80,120 +90,42 @@ public:
 
     inline auto type() const -> ValueType { return m_type; };
 
-    inline auto as_null() -> Null&
+    template <ValueType VT> inline auto as() -> ValueTypeToType<VT>::Type&
     {
-        //
         try {
-            return std::get<Null>(value);
+            return std::get<typename ValueTypeToType<VT>::Type>(value);
         } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Null\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-    inline auto as_null() const -> const Null&
-    {
-        //
-        try {
-            return std::get<Null>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Null\n",
-                value_type_to_string(this->m_type));
-            throw;
+            std::cerr << std::format("error: tried to unwrap {} as {}\n",
+                value_type_to_string(this->m_type), value_type_to_string(VT));
+            std::exit(1);
         }
     }
 
-    inline auto as_int() -> Int&
+    template <ValueType VT>
+    inline auto as() const -> const ValueTypeToType<VT>::Type&
     {
-        //
         try {
-            return std::get<Int>(value);
+            return std::get<typename ValueTypeToType<VT>::Type>(value);
         } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Int\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-    inline auto as_int() const -> const Int&
-    {
-        //
-        try {
-            return std::get<Int>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Int\n",
-                value_type_to_string(this->m_type));
-            throw;
+            std::cerr << std::format("error: tried to unwrap {} as {}\n",
+                value_type_to_string(this->m_type), value_type_to_string(VT));
+            std::exit(1);
         }
     }
 
-    inline auto as_bool() -> Bool&
-    {
-        //
-        try {
-            return std::get<Bool>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Bool\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-    inline auto as_bool() const -> const Bool&
-    {
-        //
-        try {
-            return std::get<Bool>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Bool\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
+    // clang-format off
+    inline auto as_null() -> Null& { return as<ValueType::Null>(); }
+    inline auto as_int() -> Int& { return as<ValueType::Int>(); }
+    inline auto as_bool() -> Bool& { return as<ValueType::Bool>(); }
+    inline auto as_string() -> String& { return as<ValueType::String>(); }
+    inline auto as_ptr() -> Ptr& { return as<ValueType::Ptr>(); }
 
-    inline auto as_string() -> String&
-    {
-        //
-        try {
-            return std::get<String>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as String\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-    inline auto as_string() const -> const String&
-    {
-        //
-        try {
-            return std::get<String>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as String\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-
-    inline auto as_ptr() -> Ptr&
-    {
-        //
-        try {
-            return std::get<Ptr>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Ptr\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
-    inline auto as_ptr() const -> const Ptr&
-    {
-        //
-        try {
-            return std::get<Ptr>(value);
-        } catch (const std::bad_variant_access& ex) {
-            std::cout << std::format("tried to unwrap {} as Ptr\n",
-                value_type_to_string(this->m_type));
-            throw;
-        }
-    }
+    inline auto as_null() const -> const Null& { return as<ValueType::Null>(); }
+    inline auto as_int() const -> const Int& { return as<ValueType::Int>(); }
+    inline auto as_bool() const -> const Bool& { return as<ValueType::Bool>(); }
+    inline auto as_string() const -> const String& { return as<ValueType::String>(); }
+    inline auto as_ptr() const -> const Ptr& { return as<ValueType::Ptr>(); }
+    // clang-format on
 
     inline auto to_string() const -> std::string
     {

runtime/vm.cpp

@@ -4,11 +4,70 @@
 #include <cstdlib>
 #include <format>
 #include <iostream>
+#include <string>
 #include <utility>
 #include <vector>
 
 using namespace sliger;
 
+inline auto maybe_op_to_string(uint32_t value) -> std::string
+{
+    switch (static_cast<Op>(value)) {
+        case Op::Nop:
+            return "Nop";
+        case Op::PushNull:
+            return "PushNull";
+        case Op::PushInt:
+            return "PushInt";
+        case Op::PushBool:
+            return "PushBool";
+        case Op::PushString:
+            return "PushString";
+        case Op::PushPtr:
+            return "PushPtr";
+        case Op::Pop:
+            return "Pop";
+        case Op::LoadLocal:
+            return "LoadLocal";
+        case Op::StoreLocal:
+            return "StoreLocal";
+        case Op::Call:
+            return "Call";
+        case Op::Return:
+            return "Return";
+        case Op::Jump:
+            return "Jump";
+        case Op::JumpIfFalse:
+            return "JumpIfFalse";
+        case Op::Add:
+            return "Add";
+        case Op::Subtract:
+            return "Subtract";
+        case Op::Multiply:
+            return "Multiply";
+        case Op::Divide:
+            return "Divide";
+        case Op::Remainder:
+            return "Remainder";
+        case Op::Equal:
+            return "Equal";
+        case Op::LessThan:
+            return "LessThan";
+        case Op::And:
+            return "And";
+        case Op::Or:
+            return "Or";
+        case Op::Xor:
+            return "Xor";
+        case Op::Not:
+            return "Not";
+        case Op::SourceMap:
+            return "SourceMap";
+        default:
+            return std::to_string(value);
+    }
+}
+
 void VM::run_until_done()
 {
     while (!done()) {
@@ -19,15 +78,15 @@ void VM::run_until_done()
 void VM::run_n_instructions(size_t amount)
 {
     for (size_t i = 0; !done() and i < amount; ++i) {
+
         run_instruction();
     }
 }
 
 void VM::run_instruction()
 {
-    std::cout << "stack:\n";
-    this->print_stack();
-    std::cout << std::format("pc = {}\n", this->pc);
+    std::cout << std::format("    {:>4}: {:<12}{}\n", this->pc,
+        maybe_op_to_string(this->program[this->pc]), stack_repr_string());
     auto op = eat_op();
     switch (op) {
         case Op::Nop:

runtime/vm.hpp

@@ -156,11 +156,18 @@ public:
         return this->stack;
     }
 
-    inline void print_stack() const
+    inline auto stack_repr_string() const -> std::string
     {
-        for (const auto& value : view_stack()) {
-            std::cout << std::format("    {}\n", value.to_repr_string());
+        auto result = std::string();
+        result += "→";
+        const auto& stack = view_stack();
+        for (size_t i = 0; i < stack.size(); ++i) {
+            if (i != 0) {
+                result += " ";
+            }
+            result += stack[stack.size() - i - 1].to_repr_string();
         }
+        return result;
     }
 
 private: