Currently we bail out early when the subscript dependence tester
runs into an unanalyzable dimension. That's overly pessimistic
in case further dimensions reveal non-conflicting access functions
which now happens more times as we introduce artificial dimensions
for COMPONENT_REFs.
Bootstrapped and tested on x86_64-unknown-linux-gnu, applied to trunk.
Richard.
2012-03-15 Richard Guenther <rguent...@suse.de>
PR middle-end/52580
* tree-data-ref.c (subscript_dependence_tester_1): Check
all dimensions for non-conflicting access functions.
* gfortran.dg/vect/pr52580.f: New testcase.
Index: gcc/tree-data-ref.c
===================================================================
*** gcc/tree-data-ref.c (revision 185384)
--- gcc/tree-data-ref.c (working copy)
*************** subscript_dependence_tester_1 (struct da
*** 3460,3465 ****
--- 3460,3466 ----
unsigned int i;
tree last_conflicts;
struct subscript *subscript;
+ tree res = NULL_TREE;
for (i = 0; VEC_iterate (subscript_p, DDR_SUBSCRIPTS (ddr), i, subscript);
i++)
*************** subscript_dependence_tester_1 (struct da
*** 3471,3510 ****
&overlaps_a, &overlaps_b,
&last_conflicts, loop_nest);
if (CF_NOT_KNOWN_P (overlaps_a)
|| CF_NOT_KNOWN_P (overlaps_b))
{
! finalize_ddr_dependent (ddr, chrec_dont_know);
! dependence_stats.num_dependence_undetermined++;
! free_conflict_function (overlaps_a);
! free_conflict_function (overlaps_b);
! return false;
}
else if (CF_NO_DEPENDENCE_P (overlaps_a)
|| CF_NO_DEPENDENCE_P (overlaps_b))
{
! finalize_ddr_dependent (ddr, chrec_known);
! dependence_stats.num_dependence_independent++;
! free_conflict_function (overlaps_a);
! free_conflict_function (overlaps_b);
! return false;
! }
!
! else
! {
! if (SUB_CONFLICTS_IN_A (subscript))
! free_conflict_function (SUB_CONFLICTS_IN_A (subscript));
! if (SUB_CONFLICTS_IN_B (subscript))
! free_conflict_function (SUB_CONFLICTS_IN_B (subscript));
!
! SUB_CONFLICTS_IN_A (subscript) = overlaps_a;
! SUB_CONFLICTS_IN_B (subscript) = overlaps_b;
! SUB_LAST_CONFLICT (subscript) = last_conflicts;
}
}
! return true;
}
/* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */
--- 3472,3514 ----
&overlaps_a, &overlaps_b,
&last_conflicts, loop_nest);
+ if (SUB_CONFLICTS_IN_A (subscript))
+ free_conflict_function (SUB_CONFLICTS_IN_A (subscript));
+ if (SUB_CONFLICTS_IN_B (subscript))
+ free_conflict_function (SUB_CONFLICTS_IN_B (subscript));
+
+ SUB_CONFLICTS_IN_A (subscript) = overlaps_a;
+ SUB_CONFLICTS_IN_B (subscript) = overlaps_b;
+ SUB_LAST_CONFLICT (subscript) = last_conflicts;
+
+ /* If there is any undetermined conflict function we have to
+ give a conservative answer in case we cannot prove that
+ no dependence exists when analyzing another subscript. */
if (CF_NOT_KNOWN_P (overlaps_a)
|| CF_NOT_KNOWN_P (overlaps_b))
{
! res = chrec_dont_know;
! continue;
}
+ /* When there is a subscript with no dependence we can stop. */
else if (CF_NO_DEPENDENCE_P (overlaps_a)
|| CF_NO_DEPENDENCE_P (overlaps_b))
{
! res = chrec_known;
! break;
}
}
! if (res == NULL_TREE)
! return true;
!
! if (res == chrec_known)
! dependence_stats.num_dependence_independent++;
! else
! dependence_stats.num_dependence_undetermined++;
! finalize_ddr_dependent (ddr, res);
! return false;
}
/* Computes the conflicting iterations in LOOP_NEST, and initialize DDR. */
Index: gcc/testsuite/gfortran.dg/vect/pr52580.f
===================================================================
*** gcc/testsuite/gfortran.dg/vect/pr52580.f (revision 0)
--- gcc/testsuite/gfortran.dg/vect/pr52580.f (revision 0)
***************
*** 0 ****
--- 1,33 ----
+ ! { dg-do compile }
+ ! { dg-require-effective-target vect_double }
+ SUBROUTINE CALC2
+ IMPLICIT REAL*8 (A-H, O-Z)
+ PARAMETER (N1=1335, N2=1335)
+
+ COMMON U(N1,N2), V(N1,N2), P(N1,N2),
+ * UNEW(N1,N2), VNEW(N1,N2),
+ 1 PNEW(N1,N2), UOLD(N1,N2),
+ * VOLD(N1,N2), POLD(N1,N2),
+ 2 CU(N1,N2), CV(N1,N2),
+ * Z(N1,N2), H(N1,N2), PSI(N1,N2)
+ COMMON /CONS/ DT,TDT,DX,DY,A,ALPHA,ITMAX,MPRINT,M,N,MP1,
+ 1 NP1,EL,PI,TPI,DI,DJ,PCF
+ TDTS8 = TDT/8.D0
+ TDTSDX = TDT/DX
+ TDTSDY = TDT/DY
+
+ DO 200 J=1,N
+ DO 200 I=1,M
+ UNEW(I+1,J) = UOLD(I+1,J)+
+ 1 TDTS8*(Z(I+1,J+1)+Z(I+1,J))*(CV(I+1,J+1)+CV(I,J+1)+CV(I,J)
+ 2 +CV(I+1,J))-TDTSDX*(H(I+1,J)-H(I,J))
+ VNEW(I,J+1) = VOLD(I,J+1)-TDTS8*(Z(I+1,J+1)+Z(I,J+1))
+ 1 *(CU(I+1,J+1)+CU(I,J+1)+CU(I,J)+CU(I+1,J))
+ 2 -TDTSDY*(H(I,J+1)-H(I,J))
+ PNEW(I,J) = POLD(I,J)-TDTSDX*(CU(I+1,J)-CU(I,J))
+ 1 -TDTSDY*(CV(I,J+1)-CV(I,J))
+ 200 CONTINUE
+ RETURN
+ END
+ ! { dg-final { scan-tree-dump-times "LOOP VECTORIZED" 1 "vect" } }
+ ! { dg-final { cleanup-tree-dump "vect" } }
