Re: TREE_ADDRESSABLE problem

[Richard Henderson <rth at redhat dot com>]

On Thu, Nov 20, 2003 at 12:02:56AM +0100, Jan Hubicka wrote:
> Hi,
> the following testcase taken from testustie:
> 
> typedef struct {
>   int a, b, c, d, e, f;
> } A;
> 
> void foo (A *v, int w1, int x, int *y, int *z)
> {
> }
> 
> void
> bar (A *v, int x, int y, int w2, int h)
> {
>   if (v->a != x || v->b != y) {
>     int oldw = w2;
>     int oldh = h;
>     int e = v->e;
>     int f = v->f;
>     int dx, dy;
>     foo(v, 0, 0, &w2, &h);
>     dx = (oldw - w2) * (double) e/2.0;
>     dy = (oldh - h) * (double) f/2.0;
>     x += dx;
>     y += dy;
>     v->a = x;
>     v->b = y;
>     v->c = w2;
>     v->d = h;
>   }
> }
> 
> int main ()
> {
>   A w = { 100, 110, 20, 30, -1, -1 };
>   bar (&w,400,420,50,70);
>   if (w.d != 70)
>     abort();
>   exit(0);
> }
> 
> Does not pass TREE_ADDRESSABLE check with my checking code with -O3.
> The problem is that we first compile function bar, inline foo and
> elliminate reference to w2, clear TREE_ADDRESSABLE in must_alias pass.
> Then we inline bar body into main but TREE_ADDRESSABLE is not set even
> though it is used.

Huh?  (1) w2 in bar and w2 in bar-inlined-in-main are two different
decls.  (2) w2 isn't used after optimization, ever, not even in main.


r~