On 2/2/14, 5:47 PM, deadalnix wrote:
On Sunday, 2 February 2014 at 23:55:48 UTC, Andrei Alexandrescu wrote:
On 2/2/14, 3:44 PM, Timon Gehr wrote:
On 02/03/2014 12:09 AM, Andrei Alexandrescu wrote:
A front-end pass could replace the dead dereference with a guard that
asserts the reference is not null.
I don't think this would be feasible. (The front-end pass would need to
simulate all back-end passes in order to find all the references that
might be proven dead.)
Well I was thinking of a backend-specific assertion directive. Worst
case, the front end could assign to a volatile global:
__vglobal = *p;
Andrei
As far as the backend is concerned, dereferencing and assigning to a
volatile are 2 distinct operations.
No matter. The point is the dereference will not be dead to the optimizer.
Andrei
