On Dec 19, 2007, "Daniel Berlin" <[EMAIL PROTECTED]> wrote:
> Here is the easy one: > z_5 = a_3 + b_3 > x_4 = z_5 + c_3 > DEBUG(x, x_4) > Reassoc may transform this into: > z_5 = c_3 + b_3 > x_4 = z_5 + a_3 > DEBUG(x, x_4) > Now x has the wrong value. As Andrew said, no, it doesn't. Now, if z_5 were present in a debug expression, then it would need adjusting. No different from the adjusting need for any other instruction in which z_5 was present, though. That's what I mean when I talk about letting the optimizers do their job on debug instructions too. -- Alexandre Oliva http://www.lsd.ic.unicamp.br/~oliva/ FSF Latin America Board Member http://www.fsfla.org/ Red Hat Compiler Engineer [EMAIL PROTECTED], gcc.gnu.org} Free Software Evangelist [EMAIL PROTECTED], gnu.org}
