[Bug fortran/32298] MINLOC / MAXLOC: off-by one for PARAMETER arrays

["pault at gcc dot gnu dot org" <gcc-bugzilla at gcc dot gnu dot org>]

------- Comment #3 from pault at gcc dot gnu dot org  2007-06-20 12:15 -------
This does the job by detecting the generation of a temporary. In this case the
loop is zero based but the calculated value for the position does not reflect
this.

I'll have a think about whether or not this is the cleanest way to fix the bug
and then I will submit tonight.

Paul

Index: gcc/fortran/trans-intrinsic.c
===================================================================
*** gcc/fortran/trans-intrinsic.c       (révision 125706)
--- gcc/fortran/trans-intrinsic.c       (copie de travail)
*************** gfc_conv_intrinsic_minmaxloc (gfc_se * s
*** 2046,2052 ****
    gfc_add_modify_expr (&ifblock, limit, arrayse.expr);

    /* Remember where we are.  */
!   gfc_add_modify_expr (&ifblock, pos, loop.loopvar[0]);

    ifbody = gfc_finish_block (&ifblock);

--- 2046,2060 ----
    gfc_add_modify_expr (&ifblock, limit, arrayse.expr);

    /* Remember where we are.  */
!   if (loop.temp_dim)
!     {
!       tmp = build2 (PLUS_EXPR, TREE_TYPE (pos),
!                   loop.loopvar[0],
!                   build_int_cst (type, 1));
!       gfc_add_modify_expr (&ifblock, pos, tmp);
!     }
!   else
!     gfc_add_modify_expr (&ifblock, pos, loop.loopvar[0]);

    ifbody = gfc_finish_block (&ifblock);

*************** gfc_conv_intrinsic_minmaxloc (gfc_se * s
*** 2099,2109 ****
    gfc_cleanup_loop (&loop);

    /* Return a value in the range 1..SIZE(array).  */
!   tmp = fold_build2 (MINUS_EXPR, gfc_array_index_type, loop.from[0],
!                    gfc_index_one_node);
!   tmp = fold_build2 (MINUS_EXPR, gfc_array_index_type, pos, tmp);
    /* And convert to the required type.  */
!   se->expr = convert (type, tmp);
  }

  static void
--- 2107,2120 ----
    gfc_cleanup_loop (&loop);

    /* Return a value in the range 1..SIZE(array).  */
!   if (!loop.temp_dim)
!     {
!       tmp = fold_build2 (MINUS_EXPR, gfc_array_index_type, loop.from[0],
!                        gfc_index_one_node);
!       pos = fold_build2 (MINUS_EXPR, gfc_array_index_type, pos, tmp);
!     }
    /* And convert to the required type.  */
!   se->expr = convert (type, pos);
  }

  static void
Index: gcc/testsuite/gfortran.dg/minmax_loc_1.f90
===================================================================
*** gcc/testsuite/gfortran.dg/minmax_loc_1.f90  (révision 0)
--- gcc/testsuite/gfortran.dg/minmax_loc_1.f90  (révision 0)
***************
*** 0 ****
--- 1,29 ----
+ ! { dg-do run }
+ ! Tests the fix for PR32298, in which the scalarizer would generate
+ ! a temporary in the course of evaluating MINLOC or MAXLOC, thereby
+ ! setting the start of the scalarizer loop to zero.
+ !
+ ! Contributed by Jens Bischoff <jens.bischoff@freenet.de> 
+ !
+ PROGRAM ERR_MINLOC
+ 
+    INTEGER, PARAMETER :: N = 7
+ 
+    DOUBLE PRECISION, DIMENSION (N), PARAMETER :: A &
+      = (/ 0.3D0, 0.455D0, 0.6D0, 0.7D0, 0.72D0, 0.76D0, 0.79D0 /)
+ 
+    DOUBLE PRECISION :: B
+    INTEGER          :: I, J(N), K(N)
+ 
+   DO I = 1, N
+     B = A(I)
+     J(I) = MINLOC (ABS (A - B), 1)
+     K(I) = MAXLOC (ABS (A - B), 1)
+   END DO
+ 
+   if (any (J .NE. (/1,2,3,4,5,6,7/))) call abort ()
+   if (any (K .NE. (/7,7,1,1,1,1,1/))) call abort ()
+ 
+  STOP
+ 
+ END PROGRAM ERR_MINLOC


-- 

pault at gcc dot gnu dot org changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
         AssignedTo|unassigned at gcc dot gnu   |pault at gcc dot gnu dot org
                   |dot org                     |
             Status|NEW                         |ASSIGNED
   Last reconfirmed|2007-06-12 16:05:26         |2007-06-20 12:15:24
               date|                            |


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=32298