Hello world,
the attached patch extends removing trailing TRIMs in assignments for
cases like a // trim(b). Regression-tested. OK for trunk?
Thomas
2011-05-06 Thomas König <tkoe...@gcc.gnu.org>
* frontend-passes.c (optimize_assignment): Follow chains
of concatenation operators to the end for removing trailing
TRIMS for assignments.
2011-05-06 Thomas König <tkoe...@gcc.gnu.org>
* gfortran.dg/trim_optimize_7.f90: New test.
Index: frontend-passes.c
===================================================================
--- frontend-passes.c (Revision 174391)
+++ frontend-passes.c (Arbeitskopie)
@@ -500,6 +500,14 @@ optimize_assignment (gfc_code * c)
if (lhs->ts.type == BT_CHARACTER)
{
+ /* Check for a // b // trim(c). Looping is probably not
+ necessary because the parser usually generates
+ (// (// a b ) trim(c) ) , but better safe than sorry. */
+
+ while (rhs->expr_type == EXPR_OP
+ && rhs->value.op.op == INTRINSIC_CONCAT)
+ rhs = rhs->value.op.op2;
+
if (rhs->expr_type == EXPR_FUNCTION &&
rhs->value.function.isym &&
rhs->value.function.isym->id == GFC_ISYM_TRIM)
! { dg-do run }
! { dg-options "-O -fdump-tree-original" }
! Check that trailing trims are also removed from assignment of
! expressions involving concatenations of strings .
program main
character(2) :: a,b,c
character(8) :: d
a = 'a '
b = 'b '
c = 'c '
d = a // b // a // trim(c) ! This should be optimized away.
if (d /= 'a b a c ') call abort
d = a // trim(b) // c // a ! This shouldn't.
if (d /= 'a bc a ') call abort
d = a // b // a // trim(trim(c)) ! This should also be optimized away.
if (d /= 'a b a c ') call abort
end
! { dg-final { scan-tree-dump-times "string_len_trim" 1 "original" } }
