Re: [lno] [patch] "while" with unknown loop bound

[Dorit Naishlos <DORIT at il dot ibm dot com>]

committed, along with the test-case below.

dorit

(See attached file: tree-ssa-vect-30.c)



                                                                                                                                     
                      Olga Golovanevsky                                                                                              
                                               To:       Dorit Naishlos/Haifa/IBM@IBMIL                                              
                      06/06/2004 15:35         cc:       Zdenek Dvorak <rakdver@atrey.karlin.mff.cuni.cz>, Sebastian Pop             
                                                <sebastian.pop@cri.ensmp.fr>, Devang Patel <dpatel@apple. com>,                      
                                                gcc-patches@gcc.gnu.org                                                              
                                               From:     Olga Golovanevsky/Haifa/IBM@IBMIL                                           
                                               Subject:  [lno] [patch] "while" with unknown loop bound                               
                                                                                                                                     



This patch allows vectorizing of "while" loop with unknown loop bound.
Thus, for example, the following loop will vectorize now:

  while (n--) {
    a[i] = b[i];
    i++;
  }

The patch also contains correction in cfg construction for
loop duplication in function tree_duplicate_loop_to_exit_cfg.

Bootstrapped on powerpc-apple-darwin7.0.0.

ChangeLog:

             * tree-vctorizer.c
             (vect_update_initial_conditions_of_duplicated_loop):
             Handle general form of "init" and "step" of access function.
             * tree-ssa-loop-manip.c (tree_duplicate_loop_to_exit_cfg):
             The exit from loop is taken from bb previous to latch instead
             of latch itself.



#### diffJ6_2.txt has been removed from this note on June 09, 2004 by Dorit
Naishlos

Attachment: tree-ssa-vect-30.c
Description: Binary data