Data Structures
struct	ipa_reference_local_vars_info_d
struct	ipa_reference_global_vars_info_d
struct	ipa_reference_optimization_summary_d
struct	ipa_reference_vars_info_d

Typedefs
typedef struct ipa_reference_local_vars_info_d *	ipa_reference_local_vars_info_t
typedef struct ipa_reference_global_vars_info_d *	ipa_reference_global_vars_info_t
typedef struct ipa_reference_optimization_summary_d *	ipa_reference_optimization_summary_t
typedef struct ipa_reference_vars_info_d *	ipa_reference_vars_info_t

Functions
static void	remove_node_data (struct cgraph_node node, void data)
static void	duplicate_node_data (struct cgraph_node src, struct cgraph_node dst, void *data)
static ipa_reference_vars_info_t	get_reference_vars_info ()
static ipa_reference_optimization_summary_t	get_reference_optimization_summary ()
static void	set_reference_vars_info (struct cgraph_node *node, ipa_reference_vars_info_t info)
static void	set_reference_optimization_summary (struct cgraph_node *node, ipa_reference_optimization_summary_t info)
bitmap	ipa_reference_get_not_read_global ()
bitmap	ipa_reference_get_not_written_global ()
static void	add_static_var ()
static bool	is_proper_for_analysis ()
static const char *	get_static_name ()
static void	dump_static_vars_set_to_file ()
static bool	union_static_var_sets ()
static bool	intersect_static_var_sets ()
static bitmap	copy_static_var_set ()
static void	propagate_bits ()
static void	ipa_init ()
static ipa_reference_local_vars_info_t	init_function_info ()
static void	analyze_function ()
static void	remove_node_data ()
static void	generate_summary ()
static void	read_write_all_from_decl (struct cgraph_node *node, bool &read_all, bool &write_all)
static void	get_read_write_all_from_node (struct cgraph_node *node, bool &read_all, bool &write_all)
static unsigned int	propagate ()
static bool	write_node_summary_p (struct cgraph_node *node, lto_symtab_encoder_t encoder, bitmap ltrans_statics)
static void	stream_out_bitmap (struct lto_simple_output_block *ob, bitmap bits, bitmap ltrans_statics, int ltrans_statics_bitcount)
static void	ipa_reference_write_optimization_summary ()
static void	ipa_reference_read_optimization_summary ()
static bool	gate_reference ()
ipa_opt_pass_d *	make_pass_ipa_reference ()

Variables
static splay_tree	reference_vars_to_consider
static bitmap	all_module_statics
static bitmap_obstack	local_info_obstack
static bitmap_obstack	optimization_summary_obstack
static struct cgraph_2node_hook_list *	node_duplication_hook_holder
static struct cgraph_node_hook_list *	node_removal_hook_holder
static vec < ipa_reference_vars_info_t >	ipa_reference_vars_vector
static vec < ipa_reference_optimization_summary_t >	ipa_reference_opt_sum_vector

Typedef Documentation

typedef struct ipa_reference_global_vars_info_d* ipa_reference_global_vars_info_t

typedef struct ipa_reference_local_vars_info_d* ipa_reference_local_vars_info_t

typedef struct ipa_reference_optimization_summary_d* ipa_reference_optimization_summary_t

typedef struct ipa_reference_vars_info_d* ipa_reference_vars_info_t

Function Documentation

static void add_static_var ( )

inlinestatic

Add VAR to all_module_statics and the two
   reference_vars_to_consider* sets.

References bitmap_set_bit(), dump_file, and reference_vars_to_consider.

Referenced by is_proper_for_analysis().

static void analyze_function ( )

static

This is the main routine for finding the reference patterns for
   global variables within a function FN.

References bitmap_clear(), bitmap_set_bit(), cgraph_node_cannot_return(), symtab_node_base::decl, init_function_info(), IPA_REF_ADDR, ipa_ref_cannot_lead_to_return(), IPA_REF_LOAD, IPA_REF_STORE, ipa_ref_varpool_node(), is_proper_for_analysis(), cgraph_node::local, symtab_node_base::ref_list, ipa_ref::referred, ipa_reference_local_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_written, cgraph_node::symbol, and varpool_node::symbol.

Referenced by generate_summary().

static bitmap copy_static_var_set ( )

static

Return a copy of SET on the bitmap obstack containing SET.
   But if SET is NULL or the maximum set, return that instead.

References bitmap_copy(), copy(), and bitmap_obstack::obstack.

Referenced by duplicate_node_data(), and propagate().

static void dump_static_vars_set_to_file ( )

static

Dump a set of static vars to FILE.

References get_static_name().

Referenced by propagate().

static void duplicate_node_data	(	struct cgraph_node *	src,
		struct cgraph_node *	dst,
		void *	data
	)

static

Called when new clone is inserted to callgraph late.

References copy_static_var_set(), get_reference_optimization_summary(), set_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_read, and ipa_reference_optimization_summary_d::statics_not_written.

Referenced by ipa_init(), and ipa_reference_read_optimization_summary().

static bool gate_reference ( )

static

References seen_error().

static void generate_summary ( )

static

Analyze each function in the cgraph to see which global or statics
   are read or written.

References analyze_function(), AVAIL_OVERWRITABLE, cgraph_function_body_availability(), cgraph_node_asm_name(), dump_file, get_reference_vars_info(), get_static_name(), ipa_init(), ipa_reference_vars_info_d::local, symtab_node_base::order, ipa_reference_local_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_written, and cgraph_node::symbol.

Referenced by propagate().

static void get_read_write_all_from_node	(	struct cgraph_node *	node,
		bool &	read_all,
		bool &	write_all
	)

static

Set READ_ALL/WRITE_ALL based on decl flags of NODE or any member
   in the cycle of NODE.

References AVAIL_OVERWRITABLE, cgraph_edge::callee, cgraph_node::callees, cgraph_edge_cannot_lead_to_return(), cgraph_function_body_availability(), cgraph_function_node(), dump_file, dump_flags, cgraph_indirect_call_info::ecf_flags, cgraph_node::indirect_calls, cgraph_edge::indirect_info, cgraph_edge::next_callee, and read_write_all_from_decl().

Referenced by propagate().

static ipa_reference_optimization_summary_t get_reference_optimization_summary ( )

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.

References cgraph_node::uid.

Referenced by duplicate_node_data(), ipa_reference_get_not_read_global(), ipa_reference_get_not_written_global(), ipa_reference_write_optimization_summary(), remove_node_data(), and write_node_summary_p().

static ipa_reference_vars_info_t get_reference_vars_info ( )

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.

References cgraph_node::uid.

Referenced by generate_summary(), propagate(), and propagate_bits().

static const char* get_static_name ( )

static

Lookup the tree node for the static variable that has UID and
   convert the name to a string for debugging.

References fndecl_name(), and reference_vars_to_consider.

Referenced by dump_static_vars_set_to_file(), and generate_summary().

static ipa_reference_local_vars_info_t init_function_info ( )

static

Set up the persistent info for FN.

References ipa_reference_vars_info_d::local, set_reference_vars_info(), ipa_reference_local_vars_info_d::statics_read, and ipa_reference_local_vars_info_d::statics_written.

Referenced by analyze_function().

static bool intersect_static_var_sets ( )

static

Compute X &= Y, taking into account the possibility that
   X may become the maximum set.

References all_module_statics, bitmap_and_into(), and bitmap_equal_p().

Referenced by propagate().

static void ipa_init ( )

static

The init routine for analyzing global static variable usage.  See
   comments at top for description.

References bitmap_obstack_initialize(), cgraph_add_node_duplication_hook(), cgraph_add_node_removal_hook(), dump_file, duplicate_node_data(), reference_vars_to_consider, and remove_node_data().

Referenced by generate_summary().

bitmap ipa_reference_get_not_read_global ( )

Return a bitmap indexed by DECL_UID for the static variables that
   are *not* read during the execution of the function FN.  Returns
   NULL if no data is available.

References all_module_statics, cgraph_function_node(), symtab_node_base::decl, flags_from_decl_or_type(), get_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_read, and cgraph_node::symbol.

Referenced by ref_maybe_used_by_call_p_1().

bitmap ipa_reference_get_not_written_global ( )

Return a bitmap indexed by DECL_UID for the static variables that
   are *not* written during the execution of the function FN.  Note
   that variables written may or may not be read during the function
   call.  Returns NULL if no data is available.

References all_module_statics, symtab_node_base::decl, flags_from_decl_or_type(), get_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_written, and cgraph_node::symbol.

Referenced by call_may_clobber_ref_p_1().

static void ipa_reference_read_optimization_summary ( )

static

Deserialize the ipa info for lto.

References all_module_statics, bitmap_obstack_initialize(), bitmap_set_bit(), cgraph(), cgraph_add_node_duplication_hook(), cgraph_add_node_removal_hook(), cgraph_node_asm_name(), dump_file, duplicate_node_data(), fatal_error(), fndecl_name(), len, lto_create_simple_input_block(), lto_destroy_simple_input_block(), lto_get_file_decl_data(), LTO_section_ipa_reference, lto_symtab_encoder_deref(), symtab_node_base::order, remove_node_data(), set_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_read, ipa_reference_optimization_summary_d::statics_not_written, streamer_read_hwi(), streamer_read_uhwi(), cgraph_node::symbol, and lto_file_decl_data::symtab_node_encoder.

static void ipa_reference_write_optimization_summary ( )

static

Serialize the ipa info for lto.

References bitmap_bit_p(), bitmap_set_bit(), count, symtab_node_base::decl, lto_simple_output_block::decl_state, dyn_cast(), get_reference_optimization_summary(), lto_create_simple_output_block(), lto_destroy_simple_output_block(), LTO_section_ipa_reference, lto_symtab_encoder_deref(), lto_symtab_encoder_encode(), lto_symtab_encoder_size(), lto_simple_output_block::main_stream, symtab_node_base::ref_list, reference_vars_to_consider, referenced_from_this_partition_p(), ipa_reference_optimization_summary_d::statics_not_read, ipa_reference_optimization_summary_d::statics_not_written, stream_out_bitmap(), streamer_write_uhwi_stream(), varpool_node::symbol, lto_out_decl_state::symtab_node_encoder, and write_node_summary_p().

static bool is_proper_for_analysis ( )

inlinestatic

Return true if the variable T is the right kind of static variable to
   perform compilation unit scope escape analysis.

References add_static_var(), and bitmap_bit_p().

Referenced by analyze_function(), and propagate().

ipa_opt_pass_d* make_pass_ipa_reference ( )

static unsigned int propagate ( )

static

Produce the global information by preforming a transitive closure
   on the local information that was produced by ipa_analyze_function.

References symtab_node_base::alias, all_module_statics, AVAIL_OVERWRITABLE, bitmap_and_compl(), bitmap_clear_bit(), bitmap_empty_p(), bitmap_obstack_release(), cgraph_function_body_availability(), cgraph_n_nodes, cgraph_node_asm_name(), cgraph_node_cannot_return(), copy_static_var_set(), symtab_node_base::decl, symtab_node_base::definition, dump_cgraph(), dump_file, dump_flags, dump_static_vars_set_to_file(), symtab_node_base::externally_visible, flags_from_decl_or_type(), free(), generate_summary(), get_read_write_all_from_node(), get_reference_vars_info(), ipa_reference_vars_info_d::global, intersect_static_var_sets(), ipa_discover_readonly_nonaddressable_vars(), ipa_free_postorder_info(), ipa_get_nodes_in_cycle(), ipa_print_order(), ipa_reduced_postorder(), is_proper_for_analysis(), ipa_reference_vars_info_d::local, symtab_node_base::order, order, propagate_bits(), reference_vars_to_consider, set_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_read, ipa_reference_optimization_summary_d::statics_not_written, ipa_reference_local_vars_info_d::statics_read, ipa_reference_global_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_written, ipa_reference_global_vars_info_d::statics_written, cgraph_node::symbol, varpool_node::symbol, and union_static_var_sets().

static void propagate_bits ( )

static

Compute the union all of the statics read and written by every callee of X
   into X_GLOBAL->statics_read and X_GLOBAL->statics_written.  X_GLOBAL is
   actually the set representing the cycle containing X.  If the read and
   written sets of X_GLOBAL has been reduced to the maximum set, we don't
   have to look at the remaining callees.

References all_module_statics, AVAIL_OVERWRITABLE, cgraph_edge::callee, cgraph_node::callees, cgraph_edge_cannot_lead_to_return(), cgraph_function_node(), symtab_node_base::decl, flags_from_decl_or_type(), get_reference_vars_info(), ipa_reference_vars_info_d::global, cgraph_edge::next_callee, ipa_reference_global_vars_info_d::statics_read, ipa_reference_global_vars_info_d::statics_written, cgraph_node::symbol, and union_static_var_sets().

Referenced by propagate().

static void read_write_all_from_decl	(	struct cgraph_node *	node,
		bool &	read_all,
		bool &	write_all
	)

static

Set READ_ALL/WRITE_ALL based on decl flags of NODE.

References AVAIL_OVERWRITABLE, cgraph_function_body_availability(), cgraph_node_asm_name(), cgraph_node_cannot_return(), symtab_node_base::decl, dump_file, dump_flags, flags_from_decl_or_type(), symtab_node_base::order, and cgraph_node::symbol.

Referenced by get_read_write_all_from_node().

static void remove_node_data	(	struct cgraph_node *	node,
		void *	data
	)

static

@verbatim Callgraph based analysis of static variables.

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/.

This file gathers information about how variables whose scope is
   confined to the compilation unit are used.

   The transitive call site specific clobber effects are computed
   for the variables whose scope is contained within this compilation
   unit.

   First each function and static variable initialization is analyzed
   to determine which local static variables are either read, written,
   or have their address taken.  Any local static that has its address
   taken is removed from consideration.  Once the local read and
   writes are determined, a transitive closure of this information is
   performed over the call graph to determine the worst case set of
   side effects of each call.  In later parts of the compiler, these
   local and global sets are examined to make the call clobbering less
   traumatic, promote some statics to registers, and improve aliasing
   information.

static void remove_node_data ( )

static

Called when node is removed.

References free(), get_reference_optimization_summary(), set_reference_optimization_summary(), ipa_reference_optimization_summary_d::statics_not_read, and ipa_reference_optimization_summary_d::statics_not_written.

static void set_reference_optimization_summary	(	struct cgraph_node *	node,
		ipa_reference_optimization_summary_t	info
	)

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.

References cgraph_node::uid.

Referenced by duplicate_node_data(), ipa_reference_read_optimization_summary(), propagate(), and remove_node_data().

static void set_reference_vars_info	(	struct cgraph_node *	node,
		ipa_reference_vars_info_t	info
	)

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.

References cgraph_node::uid.

Referenced by init_function_info().

static void stream_out_bitmap	(	struct lto_simple_output_block *	ob,
		bitmap	bits,
		bitmap	ltrans_statics,
		int	ltrans_statics_bitcount
	)

static

Stream out BITS&LTRANS_STATICS as list of decls to OB.
   LTRANS_STATICS_BITCOUNT specify number of bits in LTRANS_STATICS
   or -1.  When it is positive, just output -1 when
   BITS&LTRANS_STATICS == BITS&LTRANS_STATICS.

References count, lto_simple_output_block::decl_state, lto_output_var_decl_index(), lto_simple_output_block::main_stream, reference_vars_to_consider, and streamer_write_hwi_stream().

Referenced by ipa_reference_write_optimization_summary().

static bool union_static_var_sets ( )

static

Compute X |= Y, taking into account the possibility that
   either X or Y is already the maximum set.
   Return true if X is the maximum set after taking the union with Y.

References all_module_statics, bitmap_equal_p(), and bitmap_ior_into().

Referenced by propagate(), and propagate_bits().

static bool write_node_summary_p	(	struct cgraph_node *	node,
		lto_symtab_encoder_t	encoder,
		bitmap	ltrans_statics
	)

static

Return true if we need to write summary of NODE.

References bitmap_empty_p(), bitmap_intersect_p(), symtab_node_base::definition, get_reference_optimization_summary(), cgraph_node::global, cgraph_global_info::inlined_to, reachable_from_this_partition_p(), symtab_node_base::ref_list, referenced_from_this_partition_p(), ipa_reference_optimization_summary_d::statics_not_read, ipa_reference_optimization_summary_d::statics_not_written, and cgraph_node::symbol.

Referenced by ipa_reference_write_optimization_summary().

Variable Documentation

bitmap all_module_statics

static

Set of all interesting module statics.  A bit is set for every module
   static we are considering.  This is added to the local info when asm
   code is found that clobbers all memory.

Referenced by intersect_static_var_sets(), ipa_reference_get_not_read_global(), ipa_reference_get_not_written_global(), ipa_reference_read_optimization_summary(), propagate(), propagate_bits(), and union_static_var_sets().

vec<ipa_reference_optimization_summary_t> ipa_reference_opt_sum_vector

static

vec<ipa_reference_vars_info_t> ipa_reference_vars_vector

static

Vector where the reference var infos are actually stored. 
   Indexed by UID of call graph nodes.

bitmap_obstack local_info_obstack

static

Obstack holding bitmaps of local analysis (live from analysis to
   propagation)

struct cgraph_2node_hook_list* node_duplication_hook_holder

static

Holders of ipa cgraph hooks:

struct cgraph_node_hook_list* node_removal_hook_holder

static

bitmap_obstack optimization_summary_obstack

static

Obstack holding global analysis live forever.

splay_tree reference_vars_to_consider

static

This splay tree contains all of the static variables that are
   being considered by the compilation level alias analysis.

Referenced by add_static_var(), get_static_name(), ipa_init(), ipa_reference_write_optimization_summary(), propagate(), and stream_out_bitmap().

Data Structures

Typedefs

Functions

Variables

Typedef Documentation

Function Documentation

Variable Documentation