https://gcc.gnu.org/g:95b5fd731649fbc3b5720b9c81d1aa4547dfd6bf
commit r15-5491-g95b5fd731649fbc3b5720b9c81d1aa4547dfd6bf Author: Mikael Morin <mik...@gcc.gnu.org> Date: Sat Nov 18 20:54:20 2023 +0100 fortran: Check for empty MINLOC/MAXLOC ARRAY along DIM only In the function generating inline code to implement MINLOC and MAXLOC, only check for ARRAY size along DIM if DIM is present. The check for ARRAY emptyness had been checking the size of the full array, which is correct for MINLOC and MAXLOC without DIM. But if DIM is present, the reduction is along DIM only so the check for emptyness should consider that dimension only as well. This sounds like a correctness issue, but fortunately the cases where it makes a difference are cases where ARRAY is empty, so even if the value calculated for MINLOC or MAXLOC is wrong, it's wrapped in a zero iteration loop, and the wrong values are not actually used. In the end this just avoids unnecessary calculations. A previous version of this patch regressed on non-constant DIM with rank 1 ARRAY. The new testcase checks that that case is supported. gcc/fortran/ChangeLog: * trans-intrinsic.cc (gfc_conv_intrinsic_minmaxloc): Only get the size along DIM instead of the full size if DIM is present. gcc/testsuite/ChangeLog: * gfortran.dg/minmaxloc_22.f90: New test. Diff: --- gcc/fortran/trans-intrinsic.cc | 19 ++++++++++++++++++- gcc/testsuite/gfortran.dg/minmaxloc_22.f90 | 26 ++++++++++++++++++++++++++ 2 files changed, 44 insertions(+), 1 deletion(-) diff --git a/gcc/fortran/trans-intrinsic.cc b/gcc/fortran/trans-intrinsic.cc index 12bda2108bf4..8b4fd8e23312 100644 --- a/gcc/fortran/trans-intrinsic.cc +++ b/gcc/fortran/trans-intrinsic.cc @@ -5642,7 +5642,24 @@ gfc_conv_intrinsic_minmaxloc (gfc_se * se, gfc_expr * expr, enum tree_code op) if (!(maskexpr && maskexpr->rank > 0)) { mpz_t asize; - if (gfc_array_size (arrayexpr, &asize)) + bool reduction_size_known; + + if (dim_present) + { + int reduction_dim; + if (dim_arg->expr->expr_type == EXPR_CONSTANT) + reduction_dim = mpz_get_si (dim_arg->expr->value.integer) - 1; + else if (arrayexpr->rank == 1) + reduction_dim = 0; + else + gcc_unreachable (); + reduction_size_known = gfc_array_dimen_size (arrayexpr, reduction_dim, + &asize); + } + else + reduction_size_known = gfc_array_size (arrayexpr, &asize); + + if (reduction_size_known) { nonempty = gfc_conv_mpz_to_tree (asize, gfc_index_integer_kind); mpz_clear (asize); diff --git a/gcc/testsuite/gfortran.dg/minmaxloc_22.f90 b/gcc/testsuite/gfortran.dg/minmaxloc_22.f90 new file mode 100644 index 000000000000..ec97d1435af8 --- /dev/null +++ b/gcc/testsuite/gfortran.dg/minmaxloc_22.f90 @@ -0,0 +1,26 @@ +! { dg-do compile } +! { dg-additional-options "-O" } +! +! Check that the inline code generated for MINLOC and MAXLOC supports +! a non-constant DIM argument if ARRAY has rank 1. + +program p + implicit none + integer, parameter :: n = 5 + integer :: a(n), i + a = (/ (i**2, i=1,n) /) + print *, f(a, 1), g(a, 1) +contains + function f(a, d) + integer :: a(n) + integer :: d + integer :: f + f = minloc(a, dim=d) + end function + function g(a, d) + integer :: a(n) + integer :: d + integer :: g + g = maxloc(a, dim=d) + end function +end program p