re PR fortran/46896 (Wrong code with transpose(a) passed to subroutine)

2011-01-08  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/46896
	* trans-expr.c (gfc_conv_procedure_call): With a non-copying
	procedure argument (eg TRANSPOSE) use a temporary if there is
	any chance of aliasing due to host or use association.
	(arrayfunc_assign_needs_temporary): Correct logic for function
	results and do not use a temporary for implicitly PURE
	variables.  Use a temporary for Cray pointees.
	* symbol.c (gfc_add_save): Explicit SAVE not compatible with
	implicit pureness of containing procedure.
	* decl.c (match_old_style_init, gfc_match_data): Where decl
	would fail in PURE procedure, set implicit_pure to zero.
	* gfortran.h : Add implicit_pure to structure symbol_attr and
	add prototype for function gfc_implicit_pure.
	* expr.c (gfc_check_pointer_assign, gfc_check_vardef_context):
	Where decl would fail in PURE procedure, reset implicit_pure.
	* io.c (match_vtag, gfc_match_open, gfc_match_close,
	gfc_match_print, gfc_match_inquire, gfc_match_wait): The same.
	* match.c (gfc_match_critical, gfc_match_stopcode,
	sync_statement, gfc_match_allocate, gfc_match_deallocate): The
	same.
	* parse.c (decode_omp_directive): The same.
	(parse_contained): If not PURE, set implicit pure attribute.
	* resolve.c (resolve_formal_arglist, resolve_structure_cons,
	resolve_function, resolve_ordinary_assign) : The same.
	(gfc_implicit_pure): New function.
	* module.c (mio_symbol_attribute): Introduce AB_IMPLICIT_PURE
	to ab_attribute enum and use it in this function.

2011-01-08  Paul Thomas  <pault@gcc.gnu.org>

	PR fortran/46896
	* gfortran.dg/transpose_optimization_2.f90 : New test.

From-SVN: r168600

1 files changed, 7 insertions, 1 deletions

diff --git a/gcc/fortran/gfortran.h b/gcc/fortran/gfortran.h
index 1444ee8..d0377f9 100644
--- a/gcc/fortran/gfortran.h
+++ b/gcc/fortran/gfortran.h
@@ -1,6 +1,6 @@
 /* gfortran header file
    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008,
-   2009, 2010
+   2009, 2010, 2011
    Free Software Foundation, Inc.
    Contributed by Andy Vaught
 
@@ -723,6 +723,11 @@ typedef struct
   unsigned sequence:1, elemental:1, pure:1, recursive:1;
   unsigned unmaskable:1, masked:1, contained:1, mod_proc:1, abstract:1;
 
+  /* This is set if a contained procedure could be declared pure.  This is
+     used for certain optimizations that require the result or arguments
+     cannot alias.  Note that this is zero for PURE procedures.  */
+  unsigned implicit_pure:1;
+
   /* This is set if the subroutine doesn't return.  Currently, this
      is only possible for intrinsic subroutines.  */
   unsigned noreturn:1;
@@ -2736,6 +2741,7 @@ void gfc_resolve (gfc_namespace *);
 void gfc_resolve_blocks (gfc_code *, gfc_namespace *);
 int gfc_impure_variable (gfc_symbol *);
 int gfc_pure (gfc_symbol *);
+int gfc_implicit_pure (gfc_symbol *);
 int gfc_elemental (gfc_symbol *);
 gfc_try gfc_resolve_iterator (gfc_iterator *, bool);
 gfc_try find_forall_index (gfc_expr *, gfc_symbol *, int);