Re: [RFH] - Less than optimal code compiling 252.eon -O2 for x86

[Andrew Pinski]

On Jun 24, 2005, at 6:07 PM, Fariborz Jahanian wrote:

A source file mrSurfaceList.cc of 252.eon produces less efficient code initializing instance objects to 0 at -O2 than at -O1. Behavior is random and it does not happen on all x86 platforms and making the test smaller makes the problem go away. But here is what I found out is the cause.

This cannot be simplified by fold_rtx, resulting in less efficient code.

I wonder why combine can do the simplification though which is why still
produce good code for the simple testcase:
void f1(double *d,float *f2)
{
  *f2 = 0.0;
  *d = 0.0;
}

Thanks,
Andrew Pinski