Functions
static bool	reachable_at_most_once ()
static unsigned HOST_WIDE_INT	va_list_counter_bump (struct stdarg_info *si, tree counter, tree rhs, bool gpr_p)
static tree	find_va_list_reference (tree tp, int walk_subtrees, void *data)
static void	va_list_counter_op (struct stdarg_info *si, tree ap, tree var, bool gpr_p, bool write_p)
static bool	va_list_counter_struct_op (struct stdarg_info *si, tree ap, tree var, bool write_p)
static bool	va_list_ptr_read ()
static bool	va_list_ptr_write ()
static void	check_va_list_escapes ()
static bool	check_all_va_list_escapes ()
static bool	gate_optimize_stdarg ()
static unsigned int	execute_optimize_stdarg ()
gimple_opt_pass *	make_pass_stdarg ()

Function Documentation

static bool check_all_va_list_escapes ( )

static

Check all uses of temporaries from si->va_list_escape_vars bitmap.
   Return true if va_list might be escaping.

References bitmap_bit_p(), cfun, dump_file, dump_flags, get_gimple_rhs_class(), gimple_assign_cast_p(), gimple_assign_lhs(), gimple_assign_rhs1(), gimple_assign_rhs2(), gimple_assign_rhs_code(), GIMPLE_SINGLE_RHS, gsi_end_p(), gsi_next(), gsi_start_bb(), gsi_start_phis(), gsi_stmt(), host_integerp(), HOST_WIDE_INT, is_gimple_assign(), is_gimple_debug(), stdarg_info::offsets, print_gimple_stmt(), tree_low_cst(), stdarg_info::va_list_escape_vars, function::va_list_gpr_size, stdarg_info::va_list_vars, and virtual_operand_p().

Referenced by execute_optimize_stdarg().

static void check_va_list_escapes ( )

static

If RHS is X, (some type *) X or X + CST for X a temporary variable
   containing value of some va_list variable plus optionally some constant,
   either set si->va_list_escapes or add LHS to si->va_list_escape_vars,
   depending whether LHS is a function local temporary.

References stdarg_info::bb, bitmap_bit_p(), bitmap_set_bit(), stdarg_info::compute_sizes, dump_file, dump_flags, HOST_WIDE_INT_M1U, basic_block_def::index, reachable_at_most_once(), va_list_counter_bump(), stdarg_info::va_list_escape_vars, stdarg_info::va_list_escapes, stdarg_info::va_start_ap, stdarg_info::va_start_bb, and stdarg_info::va_start_count.

Referenced by execute_optimize_stdarg().

static unsigned int execute_optimize_stdarg ( )

static

Entry point to the stdarg optimization pass.

References stdarg_info::bb, bitmap_empty_p(), bitmap_set_bit(), BUILT_IN_NORMAL, calculate_dominance_info(), CDI_DOMINATORS, cfun, check_all_va_list_escapes(), check_va_list_escapes(), stdarg_info::compute_sizes, current_function_decl, function::decl, lang_hooks::decl_printable_name, dump_file, dump_flags, find_va_list_reference(), free(), get_gimple_rhs_class(), gimple_assign_lhs(), gimple_assign_rhs1(), gimple_assign_rhs2(), gimple_assign_rhs_code(), gimple_call_arg(), gimple_call_fndecl(), GIMPLE_SINGLE_RHS, gsi_end_p(), gsi_next(), gsi_start_bb(), gsi_start_phis(), gsi_stmt(), walk_stmt_info::info, integer_zerop(), is_gimple_assign(), is_gimple_call(), is_gimple_debug(), is_gimple_reg_type(), is_global_var(), memset(), stdarg_info::offsets, print_gimple_stmt(), targetm, va_list_counter_struct_op(), stdarg_info::va_list_escape_vars, stdarg_info::va_list_escapes, function::va_list_fpr_size, function::va_list_gpr_size, va_list_ptr_read(), va_list_ptr_write(), stdarg_info::va_list_vars, stdarg_info::va_start_ap, stdarg_info::va_start_bb, stdarg_info::va_start_count, virtual_operand_p(), and walk_gimple_op().

static tree find_va_list_reference	(	tree *	tp,
		int *	walk_subtrees,
		void *	data
	)

static

Called by walk_tree to look for references to va_list variables.

References bitmap_bit_p().

Referenced by execute_optimize_stdarg().

static bool gate_optimize_stdarg ( )

static

Return true if this optimization pass should be done.
   It makes only sense for stdarg functions.

References cfun, and function::stdarg.

gimple_opt_pass* make_pass_stdarg ( )

static bool reachable_at_most_once ( )

static

@verbatim Pass computing data for optimizing stdarg functions.

This file is part of GCC.

GCC is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.

GCC is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License along with GCC; see the file COPYING3. If not see http://www.gnu.org/licenses/.

A simple pass that attempts to optimize stdarg functions on architectures
   that need to save register arguments to stack on entry to stdarg functions.
   If the function doesn't use any va_start macros, no registers need to
   be saved.  If va_start macros are used, the va_list variables don't escape
   the function, it is only necessary to save registers that will be used
   in va_arg macros.  E.g. if va_arg is only used with integral types
   in the function, floating point registers don't need to be saved, etc.

Return true if basic block VA_ARG_BB is dominated by VA_START_BB and
   is executed at most as many times as VA_START_BB.

References bitmap_bit_p(), bitmap_clear(), bitmap_set_bit(), CDI_DOMINATORS, dominated_by_p(), edge_def::flags, basic_block_def::index, basic_block_def::preds, sbitmap_alloc(), sbitmap_free(), edge_def::src, stack, visited, and vNULL.

Referenced by check_va_list_escapes(), va_list_counter_op(), and va_list_ptr_read().

static unsigned HOST_WIDE_INT va_list_counter_bump	(	struct stdarg_info *	si,
		tree	counter,
		tree	rhs,
		bool	gpr_p
	)

static

For statement COUNTER = RHS, if RHS is COUNTER + constant,
   return constant, otherwise return HOST_WIDE_INT_M1U.
   GPR_P is true if this is GPR counter.

References cfun, get_base_address(), get_gimple_rhs_class(), gimple_assign_cast_p(), gimple_assign_lhs(), gimple_assign_rhs1(), gimple_assign_rhs2(), gimple_assign_rhs_code(), GIMPLE_SINGLE_RHS, host_integerp(), HOST_WIDE_INT, HOST_WIDE_INT_M1U, is_gimple_assign(), stdarg_info::offsets, tree_low_cst(), function::va_list_fpr_size, and function::va_list_gpr_size.

Referenced by check_va_list_escapes(), va_list_counter_op(), va_list_ptr_read(), and va_list_ptr_write().

static void va_list_counter_op	(	struct stdarg_info *	si,
		tree	ap,
		tree	var,
		bool	gpr_p,
		bool	write_p
	)

static

Helper function of va_list_counter_struct_op.  Compute
   cfun->va_list_{g,f}pr_size.  AP is a va_list GPR/FPR counter,
   if WRITE_P is true, seen in AP = VAR, otherwise seen in VAR = AP
   statement.  GPR_P is true if AP is a GPR counter, false if it is
   a FPR counter.

References stdarg_info::bb, cfun, stdarg_info::compute_sizes, dump_file, dump_flags, HOST_WIDE_INT, basic_block_def::index, reachable_at_most_once(), va_list_counter_bump(), function::va_list_fpr_size, function::va_list_gpr_size, stdarg_info::va_start_bb, and stdarg_info::va_start_count.

Referenced by va_list_counter_struct_op().

static bool va_list_counter_struct_op	(	struct stdarg_info *	si,
		tree	ap,
		tree	var,
		bool	write_p
	)

static

If AP is a va_list GPR/FPR counter, compute cfun->va_list_{g,f}pr_size.
   If WRITE_P is true, AP has been seen in AP = VAR assignment, if WRITE_P
   is false, AP has been seen in VAR = AP assignment.
   Return true if the AP = VAR (resp. VAR = AP) statement is a recognized
   va_arg operation that doesn't cause the va_list variable to escape
   current function.

References bitmap_bit_p(), get_base_address(), va_list_counter_op(), and stdarg_info::va_list_vars.

Referenced by execute_optimize_stdarg().

static bool va_list_ptr_read ( )

static

Check for TEM = AP.  Return true if found and the caller shouldn't
   search for va_list references in the statement.

References stdarg_info::bb, bitmap_bit_p(), bitmap_set_bit(), stdarg_info::compute_sizes, dump_file, dump_flags, HOST_WIDE_INT_M1U, basic_block_def::index, reachable_at_most_once(), va_list_counter_bump(), stdarg_info::va_list_escape_vars, stdarg_info::va_list_vars, stdarg_info::va_start_bb, and stdarg_info::va_start_count.

Referenced by execute_optimize_stdarg().

static bool va_list_ptr_write ( )

static

Check for:
     tem1 = AP;
     TEM2 = tem1 + CST;
     AP = TEM2;
   sequence and update cfun->va_list_gpr_size.  Return true if found.

References bitmap_bit_p(), cfun, stdarg_info::compute_sizes, HOST_WIDE_INT, va_list_counter_bump(), function::va_list_gpr_size, and stdarg_info::va_list_vars.

Referenced by execute_optimize_stdarg().

Functions

Function Documentation