eval_bitfield.c File Reference

#include <ctype.h>
#include "evaluator.h"
#include "mir.h"
#include "module.h"
#include "types/keywords.h"

Include dependency graph for eval_bitfield.c:

Go to the source code of this file.

Functions
void	eval_bitfield (mir_t *mir, module_t *module, ast_node_t *ast)
	Evaluates a bitfield statement.

Function Documentation

eval_bitfield()

void eval_bitfield	(	mir_t *	mir,
		module_t *	module,
		ast_node_t *	ast )

Evaluates a bitfield statement.

Parameters

mir	The MIR struct where to add the intermediate represetation.
module	Mya module where the statement is in.
ast	The AST node where start the statement.

Definition at line 9 of file eval_bitfield.c.

{
  if (ast->type != NT_STATEMENT || ast->token->value != KEY_BITFIELD) {
    module_add_error(
      module,
      ast->token->line,
      ast->token->column,
      ast->token->lexeme.length,
      "Unexpected token where is expected a bitfield statement."
    );
 
    return;
  }
 
  ast_node_t* node_name = &ast->children[0];
  ast_node_t* node_size = &ast->children[1];
 
  int64_t size = eval_expression(&mir->variables, module, node_size);
  if (size < 0 || size > 512) {
    module_add_error(
      module,
      node_size->token->line,
      node_size->token->column,
      node_size->token->lexeme.length,
      "Bitfield size should be between 0 and 512."
    );
 
    return;
  }
 
  const char* name = node_name->token->lexeme.data;
  if (! isupper(name[0])) {
    module_add_error(
      module,
      node_name->token->line,
      node_name->token->column,
      node_name->token->lexeme.length,
      "Bitfield name should start with upper case."
    );
 
    return;
  }
 
  mir_bitfield_t* bitfield = mir_add_bitfield(mir, name, size);
  if (ast->children_count != 3) {
    return;
  }
 
  ast_node_t* node_body = &ast->children[2];
  if (node_body->type != NT_BITFIELD_BODY) {
    module_add_error(
      module,
      node_body->token->line,
      node_body->token->column,
      node_body->token->lexeme.length,
      "Bitfield body declaration expected here."
    );
 
    return;
  }
 
  int64_t total_size = 0;
 
  for (int i = 0; i < node_body->children_count; i++) {
    ast_node_t* field = &node_body->children[i];
    const char* field_name = field->token->lexeme.data;
    int64_t field_size = eval_expression(&mir->variables, module, field->children);
 
    mir_bitfield_add_field(bitfield, field_name, field_size);
 
    total_size += field_size;
  }
 
  if (size != total_size) {
    module_add_error(
      module,
      node_size->token->line,
      node_size->token->column,
      node_size->token->lexeme.length,
      "Bitfield size should be equal to the sum of all field sizes."
    );
  }
}