+ return $amount unless $amount_str =~ m{^(\d+)\.(\d+)$};
+
+ my ($pre, $post) = ($1, $2);
+ my $decimals = '1' . substr($post, 0, $places);
+
+ my $propagation_limit = $Config{i32size} == 4 ? 7 : 18;
+ my $add_for_rounding = substr($post, $places, 1) >= 5 ? 1 : 0;
+
+ if ($places > $propagation_limit) {
+ $decimals = Math::BigInt->new($decimals)->badd($add_for_rounding);
+ $pre = Math::BigInt->new($decimals)->badd(1) if substr($decimals, 0, 1) eq '2';