Diego Novillo wrote:
On Mon, Oct 13, 2008 at 14:25, Reza Roboubi <reza@xxxxxxxxxx> wrote:
Can we get a better view of what the optimizer is doing, such as some hint
of which data values represent which variables inside the original C-code?
Try using -fdump-tree-all in GCC versions starting with 4.0.
Here is a simple function, calling itself in 2 places.
----------------------------------
extern int xx();
extern float yy();
extern float zz();
inline
float mm(float i, int simple)
{
float j;
if(simple > 99) return zz(i);
else {
if(i<33) j= mm(yy((int) i), xx(20));
else j=mm(yy((int) i), xx(11));
return j/4.7;
}
}
-----------------------------------------------
when we do
gcc -Wall -fdump-tree-all -Os -S test.c
test.s contains a single call to mm(), instead of two distinct calls
(correctly optimized.)
However, none of the intermediate optimization steps (such as
test.c.t93.optimized) reflects this optimization. Why?
Reza.
