Calling main

ast.cpp

@@ -63,6 +63,7 @@ enum{
   AST_DECL            = bit_flag(9),
   AST_GLOBAL          = bit_flag(10),
   AST_FLAG            = bit_flag(11),
+  AST_VAR_IS_CONST    = bit_flag(12),
 };
 
 struct Ast{
@@ -255,11 +256,15 @@ enum Ast_Decl_State{
   DECL_RESOLVING,
 };
 
+typedef S32 Register_Index;
 struct Ast_Decl: Ast{
   Ast_Decl_State state;
   Intern_String name;
 
+  // Bytecode
   void *bytecode_data_position;
+  Register_Index register_index;
+
 
   Ast_Scope *scope;
   Ast_Expr *typespec;

bytecode_codegen.cpp

@@ -9,12 +9,7 @@ bc_emit_expr(Bc *b, Ast *ast){
     // @todo pass type and figure out what to do with untyped ??
     CASE(VALUE, Atom){
       Register_Index dst = allocate_register(b);
-      switch(node->type->kind){
+      emit_load_constant(b, node->pos, dst, node->value);
-        CASE_UINT: emit_load_constant_u64(b, node->pos, dst, bigint_as_unsigned(&node->big_int_val)); break;
-        CASE_SINT: emit_load_constant_s64(b, node->pos, dst, bigint_as_signed(&node->big_int_val)); break;
-        CASE_FLOAT: emit_load_constant_f64(b, node->pos, dst, node->f64_val); break;
-        invalid_default_case;
-      }
 
       return dst;
       BREAK();
@@ -34,34 +29,96 @@ bc_emit_expr(Bc *b, Ast *ast){
   return -1;
 }
 
+struct Incomplete_Instruction{
+  Instruction *instruction;
+  Ast_Decl *decl;
+};
+
 function void
-compile_to_bc(){
+emit_stmt(Bc *b, Ast *ast){
-  Bc bc = create_bytecode_interp();
-  Bc *b = &bc;
-  For_Named(pctx->ordered_decls, ast){
   switch(ast->kind){
-
-      CASE(LAMBDA, Decl){
-        unused(node);
-        // node->bytecode_data_position = emit_lambda();
-        BREAK();
-      }
-
     CASE(VAR, Decl){
-        node->bytecode_data_position = exp_alloc(&b->memory, node->type->size, AF_ZeroMemory);
+      node->register_index = allocate_register(b);
-        if(node->expr){
+      if(is_flag_set(node->flags, AST_VAR_IS_CONST)){
-          Register_Index expression_index = bc_emit_expr(b, node->expr);
+        // emit_load_
-          Register_Index address_index = allocate_register(b);
-          emit_load_constant_address(b, node->pos, address_index, node->bytecode_data_position);
-          emit_memory(b, node->pos, BC_STORE_TO_MEMORY64, address_index, expression_index);
-          release_register(b, expression_index);
-          release_register(b, address_index);
       }
       BREAK();
     }
     default:{}
   }
 }
+
+function void
+compile_to_bc(){
+  Intern_String intern_main = pctx->intern("main"_s);
+  B32 found_main = false;
+
+  Bc bc = create_bytecode_interp();
+  Bc *b = &bc;
+
+  // Scratch scratch;
+  // auto incomplete = array_make<Incomplete_Instruction>(scratch, 512);
+
+  Register_Index main_call_register = allocate_register(b);
+  Instruction *load_main_address = emit_load_constant(b, 0, main_call_register, {});
+  emit_call(b, 0, 0);
+
+  For_Named(pctx->ordered_decls, ast){
+    switch(ast->kind){
+
+      CASE(LAMBDA, Decl){
+        Ast_Lambda *lambda = node->lambda;
+        if(!lambda->scope) break;
+        node->bytecode_data_position = b->instruction_pointer;
+
+        For(node->lambda->args){
+          it->register_index = allocate_register(b);
+        }
+
+        For(lambda->scope->stmts){
+          emit_stmt(b, it);
+        }
+
+
+        if(node->name == intern_main){
+          found_main = true;
+          load_main_address->constant.pointer = (U8 *)node->bytecode_data_position;
+          load_main_address->debug_pos = node->pos;
+          load_main_address->debug_type_flag = TYPE_POINTER;
+        }
+        BREAK();
+      }
+
+      CASE(VAR, Decl){
+        node->bytecode_data_position = exp_alloc(&b->memory, node->type->size, AF_ZeroMemory);
+        if(is_flag_set(node->flags, AST_VAR_IS_CONST)){
+          switch(node->type->kind){
+            CASE_UINT: *(U64 *)node->bytecode_data_position = bigint_as_unsigned(&node->big_int_val); break;
+            CASE_SINT: *(S64 *)node->bytecode_data_position = bigint_as_signed(&node->big_int_val); break;
+            CASE_FLOAT: *(F64 *)node->bytecode_data_position = node->f64_val; break;
+            invalid_default_case;
+          }
+        }
+        else if(node->expr) compiler_error(node->pos, "Todo: Global variable with non constant expression");
+
+        // if(node->expr){
+        //   Register_Index expression_index = bc_emit_expr(b, node->expr);
+        //   Register_Index address_index = allocate_register(b);
+        //   emit_load_constant_address(b, node->pos, address_index, node->bytecode_data_position);
+        //   emit_memory(b, node->pos, BC_STORE_TO_MEMORY64, address_index, expression_index);
+        //   release_register(b, expression_index);
+        //   release_register(b, address_index);
+        // }
+        BREAK();
+      }
+      default: {}
+    }
+  }
+
+  if(!found_main){
+    compiler_error(0, "Having a [main] function is required, it's an entry point of the application");
+  }
+
   emit_end(b);
   run_bytecode_interp(b);
   destroy_bytecode_interp(b);

bytecode_interpreter.cpp

@@ -141,7 +141,6 @@ const char *op_name[] = {
 // *End* of enum generated using code_generating_script.py
 //
 
-typedef S32 Register_Index;
 union Register{
   F64   f64;
   S64   s64;
@@ -273,53 +272,45 @@ destroy_bytecode_interp(Bc *b){
 function Instruction *
 new_instruction(Bc *b, Token *pos){
   Instruction *i         = exp_alloc_type(&b->instructions, Instruction);
+  b->instruction_pointer = i + 1;
+
   i->di               = b->dis++;
   i->debug_pos        = pos;
   return i;
 }
 
-function void
+function Instruction *
-emit_call(Bc *b, Token *pos, Register_Index register_with_call_address, Register_Index register_with_last_argument){
+emit_call(Bc *b, Token *pos, Register_Index register_with_call_address){
   auto i              = new_instruction(b, pos);
   i->operation        = BC_CALL;
   i->index_a          = register_with_call_address;
-  i->index_b          = register_with_last_argument;
+  return i;
 }
 
 function void
-emit_load_constant_f64(Bc *b, Token *pos, Register_Index dst, F64 constant){
+emit_return(Bc *b, Token *pos){
   auto i              = new_instruction(b, pos);
-  i->operation        = BC_LOAD_CONSTANT;
+  i->operation        = BC_CALL_RETURN;
-  i->constant.f64     = constant;
-  i->index_c          = dst;
-  i->debug_type_flag  = TYPE_F64;
 }
 
-function void
+function Instruction *
-emit_load_constant_s64(Bc *b, Token *pos, Register_Index dst, S64 constant){
+emit_load_constant(Bc *b, Token *pos, Register_Index dst, Value value){
   auto i              = new_instruction(b, pos);
   i->operation        = BC_LOAD_CONSTANT;
-  i->constant.s64     = constant;
   i->index_c          = dst;
-  i->debug_type_flag  = TYPE_S64;
+
+  if(value.type){
+    i->debug_type_flag  = value.type->kind;
+    switch(value.type->kind){
+      case TYPE_POINTER:
+      CASE_UINT: i->constant.u64 = bigint_as_unsigned(&value.big_int_val); break;
+      CASE_SINT: i->constant.s64 = bigint_as_signed(&value.big_int_val); break;
+      CASE_FLOAT: i->constant.f64 = value.f64_val; break;
+      invalid_default_case;
+    }
   }
 
-function void
+  return i;
-emit_load_constant_u64(Bc *b, Token *pos, Register_Index dst, U64 constant){
-  auto i              = new_instruction(b, pos);
-  i->operation        = BC_LOAD_CONSTANT;
-  i->constant.u64     = constant;
-  i->index_c          = dst;
-  i->debug_type_flag  = TYPE_U64;
-}
-
-function void
-emit_load_constant_address(Bc *b, Token *pos, Register_Index dst, void *address){
-  auto i              = new_instruction(b, pos);
-  i->operation        = BC_LOAD_CONSTANT;
-  i->constant.pointer = (U8 *)address;
-  i->index_c          = dst;
-  i->debug_type_flag  = TYPE_POINTER;
 }
 
 function void
@@ -356,15 +347,14 @@ emit_arithmetic(Bc *b, Token *pos, Operation ins, Register_Index left, Register_
 function void
 emit_end(Bc *b){
   Instruction *i      = new_instruction(b, 0);
-  i->di               = b->dis++;
   i->operation        = BC_END_OF_INSTRUCTIONS;
 }
 
 #define R(x) (b->registers[b->top_call->first_register_index_in_window + (x)]) // Get register
-#define bc_stack_push(b, T) (T *)bc__stack_push(b, sizeof(T))
+#define bc_stack_push(b, T) (T *)bc_stack_push_size(b, sizeof(T))
 
 function U8 *
-bc__stack_push(Bc *b, U64 size){
+bc_stack_push_size(Bc *b, U64 size){
   U8 *result = (U8 *)b->stack_pointer;
   b->stack_pointer += size;
   assert(b->stack_pointer < b->stack_top);
@@ -435,7 +425,6 @@ run_bytecode_interp(Bc *b){
 
       case BC_CALL:{
         Register_Index register_with_call_address = instr->index_a;
-        // Register_Index register_with_last_argument = instr->index_b;
         Call_Frame *call = bc_push_call_frame(b, register_with_call_address);
         call->saved_instruction_pointer = b->instruction_pointer;
         b->instruction_pointer = (Instruction *)R(register_with_call_address).pointer;

code_generating_script.py

@@ -91,6 +91,8 @@ if True:
   result += "};\n"
   update_file("bytecode_interpreter.cpp", "enum", result)
 
+
+
 #
 # Generate switch cases
 #

programs/vm.kl

@@ -2,4 +2,4 @@
 global_variable := 10 + 29
 
 main :: ()
-  pass // a := 10 + 20
+  a := 10 + 20 // a := 10 + 20

typechecking.cpp

@@ -1395,6 +1395,10 @@ resolve_decl(Ast_Decl *ast){
         }
 
         try_propagating_resolved_type_to_untyped_literals(node->expr, node->type);
+
+        if(op.is_const){
+          set_flag(node->flags, AST_VAR_IS_CONST);
+        }
         BREAK();
       }