From patchwork Sun May 1 09:49:49 2011 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit Subject: [fortran] Eliminate duplicate function calls with rank>0 and unknown shape Date: Sat, 30 Apr 2011 23:49:49 -0000 From: Thomas Koenig X-Patchwork-Id: 93541 Message-Id: <4DBD2CBD.2040502@netcologne.de> To: "fortran@gcc.gnu.org" , gcc-patches Hello world, after Paul's fix for allocate on assignment (thanks Paul!), here is a patch for the original test case from PR 22572, where the bounds of the function are unknown at compile time. This uses an allocatable temporary. In the long run, another option is to use interface mapping to evaluate the bounds of intrinsics and explicit-shape functions. For this, it would be necessary to write a front-end-only version of gfc_evaluate_now, which would be complicated by the desire not to disturb common function elimination, so I've put that on the back burner for now. Regression-tested. OK for trunk? Thomas 2011-05-01 Thomas Koenig PR fortran/22572 * frontend-passes.c (cfe_register_funcs): Also register functions for potential elimination if the rank is > 0, the shape is unknown and reallocate on assignment is active. (create_var): For rank > 0 functions with unknown shape, create an allocatable temporary. 2011-05-01 Thomas Koenig PR fortran/22572 * function_optimize_7.f90: New test case. ! { dg-do compile } ! { dg-options "-O -fdump-tree-original -Warray-temporaries" } subroutine xx(n, m, a, b, c, d, x, z, i, s_in, s_out) implicit none integer, intent(in) :: n, m real, intent(in), dimension(n,n) :: a, b, c real, intent(out), dimension(n,n) :: d real, intent(in), dimension(n,m) :: s_in real, intent(out), dimension(m) :: s_out integer, intent(out) :: i real, intent(inout) :: x real, intent(out) :: z character(60) :: line real, external :: ext_func interface elemental function element(x) real, intent(in) :: x real :: elem end function element pure function mypure(x) real, intent(in) :: x integer :: mypure end function mypure elemental impure function elem_impure(x) real, intent(in) :: x real :: elem_impure end function elem_impure end interface d = matmul(a,b) + matmul(a,b) ! { dg-warning "Creating array temporary" } z = sin(x) + cos(x) + sin(x) + cos(x) x = ext_func(a) + 23 + ext_func(a) z = element(x) + element(x) i = mypure(x) - mypure(x) z = elem_impure(x) - elem_impure(x) s_out = sum(s_in,1) + 3.14 / sum(s_in,1) ! { dg-warning "Creating array temporary" } end subroutine xx ! { dg-final { scan-tree-dump-times "matmul_r4" 1 "original" } } ! { dg-final { scan-tree-dump-times "__builtin_sinf" 1 "original" } } ! { dg-final { scan-tree-dump-times "__builtin_cosf" 1 "original" } } ! { dg-final { scan-tree-dump-times "ext_func" 2 "original" } } ! { dg-final { scan-tree-dump-times "element" 1 "original" } } ! { dg-final { scan-tree-dump-times "mypure" 1 "original" } } ! { dg-final { scan-tree-dump-times "elem_impure" 2 "original" } } ! { dg-final { scan-tree-dump-times "sum_r4" 1 "original" } } ! { dg-final { cleanup-tree-dump "original" } } Index: frontend-passes.c =================================================================== --- frontend-passes.c (Revision 173214) +++ frontend-passes.c (Arbeitskopie) @@ -152,11 +152,11 @@ cfe_register_funcs (gfc_expr **e, int *walk_subtre if ((*e)->ts.type == BT_CHARACTER) return 0; - /* If we don't know the shape at compile time, we do not create a temporary - variable to hold the intermediate result. FIXME: Change this later when - allocation on assignment works for intrinsics. */ + /* If we don't know the shape at compile time, we create an allocatable + temporary variable to hold the intermediate result, but only if + allocation on assignment is active. */ - if ((*e)->rank > 0 && (*e)->shape == NULL) + if ((*e)->rank > 0 && (*e)->shape == NULL && !gfc_option.flag_realloc_lhs) return 0; /* Skip the test for pure functions if -faggressive-function-elimination @@ -250,22 +250,38 @@ create_var (gfc_expr * e) symbol = symtree->n.sym; symbol->ts = e->ts; - symbol->as = gfc_get_array_spec (); - symbol->as->rank = e->rank; - symbol->as->type = AS_EXPLICIT; - for (i=0; irank; i++) + + if (e->rank > 0) { - gfc_expr *p, *q; + symbol->as = gfc_get_array_spec (); + symbol->as->rank = e->rank; + + if (e->shape == NULL) + { + /* We don't know the shape at compile time, so we use an + allocatable. */ + symbol->as->type = AS_DEFERRED; + symbol->attr.allocatable = 1; + } + else + { + symbol->as->type = AS_EXPLICIT; + /* Copy the shape. */ + for (i=0; irank; i++) + { + gfc_expr *p, *q; - p = gfc_get_constant_expr (BT_INTEGER, gfc_default_integer_kind, - &(e->where)); - mpz_set_si (p->value.integer, 1); - symbol->as->lower[i] = p; - - q = gfc_get_constant_expr (BT_INTEGER, gfc_index_integer_kind, - &(e->where)); - mpz_set (q->value.integer, e->shape[i]); - symbol->as->upper[i] = q; + p = gfc_get_constant_expr (BT_INTEGER, gfc_default_integer_kind, + &(e->where)); + mpz_set_si (p->value.integer, 1); + symbol->as->lower[i] = p; + + q = gfc_get_constant_expr (BT_INTEGER, gfc_index_integer_kind, + &(e->where)); + mpz_set (q->value.integer, e->shape[i]); + symbol->as->upper[i] = q; + } + } } symbol->attr.flavor = FL_VARIABLE;