diff options
| author | tkoenig <tkoenig@138bc75d-0d04-0410-961f-82ee72b054a4> | 2012-06-07 11:11:55 +0000 |
|---|---|---|
| committer | tkoenig <tkoenig@138bc75d-0d04-0410-961f-82ee72b054a4> | 2012-06-07 11:11:55 +0000 |
| commit | af87b36a63faa205fc1a2f4b7072ba16b9a4898f (patch) | |
| tree | 45b7207b0fa91090d90b3a9db729bafd16702830 /gcc/fortran/frontend-passes.c | |
| parent | 3b890ce749236442acf81936f41e2254d8599193 (diff) | |
| download | gcc-af87b36a63faa205fc1a2f4b7072ba16b9a4898f.tar.gz | |
2012-06-07 Thomas König <tkoenig@gcc.gnu.org>
PR fortran/52861
* frontend-passes (empty_string): Add prototype.
(optimize_assignment): Set the length of an empty string
constant to zero.
2012-06-07 Thomas König <tkoenig@gcc.gnu.org>
PR fortran/52861
* gfortran.dg/string_assign_1.f90: New test case.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@188300 138bc75d-0d04-0410-961f-82ee72b054a4
Diffstat (limited to 'gcc/fortran/frontend-passes.c')
| -rw-r--r-- | gcc/fortran/frontend-passes.c | 14 |
1 files changed, 10 insertions, 4 deletions
diff --git a/gcc/fortran/frontend-passes.c b/gcc/fortran/frontend-passes.c index 40ca0745a1f..4fd24c2947e 100644 --- a/gcc/fortran/frontend-passes.c +++ b/gcc/fortran/frontend-passes.c @@ -1,5 +1,5 @@ /* Pass manager for Fortran front end. - Copyright (C) 2010, 2011 Free Software Foundation, Inc. + Copyright (C) 2010, 2011, 2012 Free Software Foundation, Inc. Contributed by Thomas König. This file is part of GCC. @@ -37,6 +37,7 @@ static bool optimize_comparison (gfc_expr *, gfc_intrinsic_op); static bool optimize_trim (gfc_expr *); static bool optimize_lexical_comparison (gfc_expr *); static void optimize_minmaxloc (gfc_expr **); +static bool empty_string (gfc_expr *e); /* How deep we are inside an argument list. */ @@ -734,10 +735,15 @@ optimize_assignment (gfc_code * c) lhs = c->expr1; rhs = c->expr2; - /* Optimize away a = trim(b), where a is a character variable. */ - if (lhs->ts.type == BT_CHARACTER) - remove_trim (rhs); + { + /* Optimize away a = trim(b), where a is a character variable. */ + remove_trim (rhs); + + /* Replace a = ' ' by a = '' to optimize away a memcpy. */ + if (empty_string(rhs)) + rhs->value.character.length = 0; + } if (lhs->rank > 0 && gfc_check_dependency (lhs, rhs, true) == 0) optimize_binop_array_assignment (c, &rhs, false); |