re PR fortran/22572 (Double occurrence of matmul intrinsic not optimised)

re PR fortran/22572 (Double occurrence of matmul intrinsic not optimised)

2010-03-21  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/22572
	* gfortran.h (gfc_option_t) : Add
	flag_aggressive_function_elimination.
	(gfc_dep_compare_functions):  Add prototype.
	* lang.opt: Add faggressive-function-elimination.
	* invoke.texi: Document -faggressive-function-elimination.
	* frontend_passes (expr_array):  New static variable.
	(expr_size):  Likewise.
	(expr_count):  Likewise.
	(current_code):  Likewise.
	(current_ns):  Likewise.
	(gfc_run_passes):  Allocate and free space for expressions.
	(cfe_register_funcs):  New function.
	(create_var):  New function.
	(cfc_expr_0):  New function.
	(cfe_code):  New function.
	(optimize_namespace):  Invoke gfc_code_walker with cfe_code
	and cfe_expr_0.
	* dependency.c (gfc_dep_compare_functions):  New function.
	(gfc_dep_compare_expr):  Use it.
	* options.c (gfc_init_options):  Handle
	flag_aggressive_function_elimination.
	(gfc_handle_option):  Likewise.

2010-03-21  Thomas Koenig  <tkoenig@gcc.gnu.org>

	PR fortran/22572
	* gfortran.dg/function_optimize_1.f90:  New test.
	* gfortran.dg/function_optimize_2.f90:  New test.

From-SVN: r171207