This fixes PR59038 by reverting the wrong fix for PR58955 and instead
installing the correct fix (fingers crossing).
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied.
Richard.
2013-11-07 Richard Biener <rguent...@suse.de>
PR tree-optimization/59038
PR tree-optimization/58955
* tree-loop-distribution.c (pg_add_dependence_edges): Revert
previous change. Handle known dependences correctly.
* gcc.dg/torture/pr59038.c: New testcase.
Index: gcc/tree-loop-distribution.c
===================================================================
*** gcc/tree-loop-distribution.c (revision 204506)
--- gcc/tree-loop-distribution.c (working copy)
*************** pg_add_dependence_edges (struct graph *r
*** 1324,1330 ****
for (int ii = 0; drs1.iterate (ii, &dr1); ++ii)
for (int jj = 0; drs2.iterate (jj, &dr2); ++jj)
{
! int this_dir = -1;
ddr_p ddr;
/* Re-shuffle data-refs to be in dominator order. */
if (rdg_vertex_for_stmt (rdg, DR_STMT (dr1))
--- 1324,1330 ----
for (int ii = 0; drs1.iterate (ii, &dr1); ++ii)
for (int jj = 0; drs2.iterate (jj, &dr2); ++jj)
{
! int this_dir = 1;
ddr_p ddr;
/* Re-shuffle data-refs to be in dominator order. */
if (rdg_vertex_for_stmt (rdg, DR_STMT (dr1))
*************** pg_add_dependence_edges (struct graph *r
*** 1350,1357 ****
}
/* Known dependences can still be unordered througout the
iteration space, see gcc.dg/tree-ssa/ldist-16.c. */
! if (DDR_NUM_DIST_VECTS (ddr) == 0)
this_dir = 2;
}
else
this_dir = 0;
--- 1350,1366 ----
}
/* Known dependences can still be unordered througout the
iteration space, see gcc.dg/tree-ssa/ldist-16.c. */
! if (DDR_NUM_DIST_VECTS (ddr) != 1)
this_dir = 2;
+ /* If the overlap is exact preserve stmt order. */
+ else if (lambda_vector_zerop (DDR_DIST_VECT (ddr, 0), 1))
+ ;
+ else
+ {
+ /* Else as the distance vector is lexicographic positive
+ swap the dependence direction. */
+ this_dir = -this_dir;
+ }
}
else
this_dir = 0;
Index: gcc/testsuite/gcc.dg/torture/pr59038.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr59038.c (revision 0)
--- gcc/testsuite/gcc.dg/torture/pr59038.c (working copy)
***************
*** 0 ****
--- 1,25 ----
+ /* { dg-do run } */
+
+ extern void abort (void);
+
+ unsigned char first_ones_8bit[256];
+ unsigned char connected_passed[256];
+
+ int
+ main ()
+ {
+ int i, j;
+ for (i=0;i<256;i++){
+ connected_passed[i]=0;
+ first_ones_8bit[i]=0;
+ for (j=7;j>0;j--){
+ if ((i & (3<<(7-j))) == (3<<(7-j))){
+ connected_passed[i]=j;
+ break;
+ }
+ }
+ }
+ if (connected_passed[3] != 7)
+ abort ();
+ return 0;
+ }
