On Thu, Apr 17, 2008 at 5:20 PM, Richard Guenther <[EMAIL PROTECTED]> wrote: > > On Thu, Apr 17, 2008 at 1:35 PM, Sandeep Maram <[EMAIL PROTECTED]> wrote: > > > > On Tue, Apr 15, 2008 at 3:00 PM, Richard Guenther > > <[EMAIL PROTECTED]> wrote: > > > > > > On Tue, Apr 15, 2008 at 7:49 AM, Sandeep Maram <[EMAIL PROTECTED]> > wrote: > > > > On Tue, Apr 15, 2008 at 10:34 AM, Daniel Berlin <[EMAIL PROTECTED]> > wrote: > > > > > To clarify what Richard means, your assertion that "you have > updated > > > > > SSA information" is false. > > > > > If you had updated the SSA information, the error would not > occur :). > > > > > > > > > > How exactly are you updating the ssa information? > > > > > > > > I am calling update_ssa (TODO_update_ssa), after all the statements > > > > are transferred. > > > > > > > > > > > > > > > > > > The general way to update SSA for this case would be: > > > > > > > > > > For each statement you have moved: > > > > > Call update_stmt (t); > > > > > > > > > > Then call update_ssa (TODO_update_ssa) (or instead use > > > > > rewrite_into_loop_closed_ssa if this is a loop pass). > > > > > > > > > > If you do not call update_stmt in this case, update_ssa won't > actually > > > > > do anything. > > > > > > > > > > Diego, the bsi iterators do not update the statements for you > though > > > > > it is not clear if this is a bug or not. > > > > > > > > > > The bsi iterators call update_modified_stmts, which says: > > > > > > > > > > /* Mark statement T as modified, and update it. */ > > > > > static inline void > > > > > update_modified_stmts (tree t) > > > > > > > > > > However, this only calls update_stmt_if_modified (IE it does not > mark > > > > > the statement as modified and update it, as it claims to). > > > > > > > > > > Sandeep, it should also suffice to call mark_stmt_modified > *before* > > > > > moving the statements (since the above routine should then update > > > > > them). > > > > > > > > > > > > > Thanks. I will use update_stmt, update_ssa now. > > > > > > You need to do more than that - you appearantly are moving uses of > > > SSA names to a place where its definition is not available like if you > do > > > > > > b_1 = 1; > > > a_1 = b_1 + 1; > > > > > > and transform this to > > > > > > a_1 = b_1 + 1; > > > b_1 = 1; > > > > > > which obviously cannot work. So "updating" SSA form won't help you > > > and renaming the symbols will only make the verifier happy and leave > > > you with wrong code. > > > > > > So you need to investigate what exactly you are doing wrong with > > > your stmt movement. > > > > I am considering two consequent fusible loops. These loops have a > > single header and a single latch. I want to move the statements in > > the header of the second loop to the header of the first loop. This > > function will be called only after certain constraints are met. That > > is legality test is performed before fusing these loops. > > > > I think I am transfering all the statements inside the loop correctly. > > But I am doing some mistake with the "iterator variable". > > Well, we cannot do mind-reading here to figure out what exactly you > do wrong. Please have a look at the tree-dumps before and after > your transformation (-fdump-tree-all-vops), this should obviously > explain what is going wrong. I suppose you simply forgot about > PHI nodes.
Thank you. Regards, Sandeep. > > Richard. >
