Evaluate expressions in switch cases

1 files changed, 37 insertions, 10 deletions

diff --git a/switch.c b/switch.c
index 305914c..a7f2e2b 100644
--- a/switch.c
+++ b/switch.c
@@ -50,16 +50,27 @@ compare_cases (const void *a,
 }
 
 static gboolean
-constant_expression (ast_expression_t *expr)
+constant_expression (ast_expression_t *expr,
+		     value_t	      *value)
 {
+    value_t left;
+    value_t right;
+    value_t result;
+    
     g_assert (((ast_t *)expr)->common.type == AST_EXPRESSION);
 	
     switch (expr->common.type)
     {
     case AST_INT_LITERAL_EXPRESSION:
+	value->int32_val = expr->int_literal.value;
+	break;
+	
     case AST_BOOL_LITERAL_EXPRESSION:
+	value->bool_val = expr->bool_literal.value;
+	break;
+	
     case AST_NULL_EXPRESSION:
-	return TRUE;
+	value->pointer_val = NULL;
 	break;
 	
     case AST_IDENTIFIER_EXPRESSION:
@@ -78,29 +89,43 @@ constant_expression (ast_expression_t *expr)
 	break;
 	
     case AST_UNARY_EXPRESSION:
-	if (!constant_expression (expr->unary.expr))
+	if (!constant_expression (expr->unary.expr, &result))
 	    return FALSE;
+
+	evaluate_unary_operator (expr->unary.operator,
+				 expr->unary.expr->common.type_spec, &result,
+				 expr->common.type_spec, value);
 	break;
 	
     case AST_BINARY_EXPRESSION:
-	if (!constant_expression (expr->binary.left))
+	if (!constant_expression (expr->binary.left, &left))
 	    return FALSE;
 
-	if (!constant_expression (expr->binary.right))
+	if (!constant_expression (expr->binary.right, &right))
 	    return FALSE;
+
+	evaluate_binary_operator (expr->binary.operator,
+				  expr->binary.left->common.type_spec, &left,
+				  expr->binary.right->common.type_spec, &right,
+				  expr->common.type_spec, value);
 	break;
 	
     case AST_TERNARY_EXPRESSION:
-	if (!constant_expression (expr->ternary.cond))
+	if (!constant_expression (expr->ternary.cond, &result))
 	    return FALSE;
 
 	/* FIXME: we could require only the taken branch to be constant */
-	
-	if (!constant_expression (expr->ternary.then_expr))
+
+	if (!constant_expression (expr->ternary.then_expr, &left))
 	    return FALSE;
 
-	if (!constant_expression (expr->ternary.else_expr))
+	if (!constant_expression (expr->ternary.else_expr, &right))
 	    return FALSE;
+
+	if (result.bool_val)
+	    *value = left;
+	else
+	    *value = right;
 	break;
     }
 
@@ -120,10 +145,12 @@ check_constant_case_expressions (ast_t *ast)
 
     if (ast_is (ast, AST_CASE, AST_EXPRESSION_CASE))
     {
+	value_t value;
+	
 	/* FIXME: check that we are dealing with a constant expression,
 	 * and store the value of that expression in the case clause
 	 */
-	if (!constant_expression (ast->case_.expression.expression))
+	if (!constant_expression (ast->case_.expression.expression, &value))
 	{
 	    g_print ("Expression in case clause must be constant\n");