ipa-reference.cc File Reference

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "tree.h"
#include "gimple.h"
#include "tree-pass.h"
#include "cgraph.h"
#include "data-streamer.h"
#include "calls.h"
#include "ipa-utils.h"
#include "ipa-reference.h"
#include "alloc-pool.h"
#include "symbol-summary.h"

Include dependency graph for ipa-reference.cc:

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
class	ipa_ref_var_info_summary_t
class	ipa_ref_opt_summary_t

Typedefs
typedef ipa_reference_local_vars_info_d *	ipa_reference_local_vars_info_t
typedef ipa_reference_global_vars_info_d *	ipa_reference_global_vars_info_t
typedef ipa_reference_optimization_summary_d *	ipa_reference_optimization_summary_t
typedef struct ipa_reference_vars_info_d *	ipa_reference_vars_info_t
typedef hash_map< tree, int >	reference_vars_map_t

Functions
int	ipa_reference_var_uid (tree t)
int	ipa_reference_var_get_or_insert_uid (tree t, bool *existed)
static ipa_reference_vars_info_t	get_reference_vars_info (struct cgraph_node *node)
static ipa_reference_optimization_summary_t	get_reference_optimization_summary (struct cgraph_node *node)
bitmap	ipa_reference_get_read_global (struct cgraph_node *fn)
bitmap	ipa_reference_get_written_global (struct cgraph_node *fn)
static bool	is_improper (symtab_node *n, void *v)
static bool	is_proper_for_analysis (tree t)
static const char *	get_static_name (int index)
static void	dump_static_vars_set_to_file (FILE *f, bitmap set)
static bool	union_static_var_sets (bitmap &x, bitmap y)
static bitmap	copy_static_var_set (bitmap set, bool for_propagation)
static void	propagate_bits (ipa_reference_global_vars_info_t x_global, struct cgraph_node *x)
static void	varpool_removal_hook (varpool_node *node, void *)
static void	ipa_init (void)
static ipa_reference_local_vars_info_t	init_function_info (struct cgraph_node *fn)
static void	analyze_function (struct cgraph_node *fn)
static void	generate_summary (void)
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 bool	ignore_edge_p (cgraph_edge *e)
static unsigned int	propagate (void)
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 (void)
static void	ipa_reference_read_optimization_summary (void)
ipa_opt_pass_d *	make_pass_ipa_reference (gcc::context *ctxt)
void	ipa_reference_cc_finalize (void)

Variables
static reference_vars_map_t *	ipa_reference_vars_map
static int	ipa_reference_vars_uids
static vec< tree > *	reference_vars_to_consider
varpool_node_hook_list *	varpool_node_hooks
static bitmap	all_module_statics
static bitmap	no_module_statics
static bitmap	ignore_module_statics
static bitmap_obstack	local_info_obstack
static bitmap_obstack	optimization_summary_obstack
static ipa_ref_var_info_summary_t *	ipa_ref_var_info_summaries = NULL
static ipa_ref_opt_summary_t *	ipa_ref_opt_sum_summaries = NULL
static bool	ipa_init_p = false

Typedef Documentation

ipa_reference_global_vars_info_t

typedef ipa_reference_global_vars_info_d* ipa_reference_global_vars_info_t

ipa_reference_local_vars_info_t

typedef ipa_reference_local_vars_info_d* ipa_reference_local_vars_info_t

ipa_reference_optimization_summary_t

typedef ipa_reference_optimization_summary_d* ipa_reference_optimization_summary_t

ipa_reference_vars_info_t

typedef struct ipa_reference_vars_info_d* ipa_reference_vars_info_t

reference_vars_map_t

typedef hash_map<tree, int> reference_vars_map_t

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

Function Documentation

analyze_function()

static void analyze_function ( struct cgraph_node * fn )

static

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

References all_module_statics, bitmap_clear(), bitmap_set_bit, ipa_ref::cannot_lead_to_return(), cgraph_node::cannot_return_p(), symtab_node::decl, dump_file, gcc_unreachable, i, init_function_info(), IPA_REF_ADDR, IPA_REF_LOAD, IPA_REF_STORE, ipa_reference_var_get_or_insert_uid(), is_a(), is_proper_for_analysis(), symtab_node::iterate_reference(), cgraph_node::local, NULL, opt_for_fn, reference_vars_to_consider, ipa_ref::referred, ipa_reference_local_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_written, and ipa_ref::use.

Referenced by generate_summary().

copy_static_var_set()

static bitmap copy_static_var_set ( bitmap set, bool for_propagation )

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 all_module_statics, BITMAP_ALLOC, bitmap_copy(), gcc_checking_assert, no_module_statics, and NULL.

Referenced by ipa_ref_opt_summary_t::duplicate(), and propagate().

dump_static_vars_set_to_file()

static void dump_static_vars_set_to_file ( FILE * f, bitmap set )

static

Dump a set of static vars to FILE.   

References all_module_statics, EXECUTE_IF_SET_IN_BITMAP, get_static_name(), no_module_statics, and NULL.

Referenced by propagate().

generate_summary()

static void generate_summary ( void )

static

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

References symtab_node::alias, all_module_statics, analyze_function(), AVAIL_INTERPOSABLE, bitmap_set_bit, symtab_node::decl, dump_file, symtab_node::dump_name(), EXECUTE_IF_SET_IN_BITMAP, FOR_EACH_DEFINED_FUNCTION, cgraph_node::get_availability(), get_reference_vars_info(), get_static_name(), i, ignore_module_statics, ipa_init(), ipa_reference_var_uid(), is_a(), is_proper_for_analysis(), symtab_node::iterate_reference(), ipa_reference_vars_info_d::local, NULL, opt_for_fn, ipa_ref::referred, ipa_reference_local_vars_info_d::statics_read, and ipa_reference_local_vars_info_d::statics_written.

Referenced by propagate().

get_read_write_all_from_node()

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 symtab_node::analyzed, AVAIL_INTERPOSABLE, cgraph_edge::callee, cgraph_node::callees, cgraph_edge::cannot_lead_to_return_p(), symtab_node::decl, dump_file, dump_flags, ECF_CONST, cgraph_indirect_call_info::ecf_flags, ECF_PURE, cgraph_node::function_symbol(), gcc_checking_assert, cgraph_node::get_availability(), cgraph_node::indirect_calls, cgraph_edge::indirect_info, cgraph_edge::next_callee, opt_for_fn, read_write_all_from_decl(), and TDF_DETAILS.

Referenced by propagate().

get_reference_optimization_summary()

static ipa_reference_optimization_summary_t get_reference_optimization_summary ( struct cgraph_node * node )

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.   

References ipa_ref_opt_sum_summaries, and NULL.

Referenced by ipa_reference_get_read_global(), ipa_reference_get_written_global(), ipa_reference_write_optimization_summary(), and write_node_summary_p().

get_reference_vars_info()

static ipa_reference_vars_info_t get_reference_vars_info ( struct cgraph_node * node )

inlinestatic

Return the ipa_reference_vars structure starting from the cgraph NODE.   

References ipa_ref_var_info_summaries, and NULL.

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

get_static_name()

static const char * get_static_name ( int index )

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().

ignore_edge_p()

static bool ignore_edge_p ( cgraph_edge * e )

static

Skip edges from and to nodes without ipa_reference enabled.
Ignore not available symbols.  This leave
them out of strongly connected components and makes them easy to skip in the
propagation loop bellow.   

References AVAIL_INTERPOSABLE, cgraph_edge::callee, cgraph_edge::caller, symtab_node::decl, ECF_LEAF, flags_from_decl_or_type(), cgraph_node::function_or_virtual_thunk_symbol(), and opt_for_fn.

init_function_info()

static ipa_reference_local_vars_info_t init_function_info ( struct cgraph_node * fn )

static

Set up the persistent info for FN.   

References BITMAP_ALLOC, ipa_reference_vars_info_d::global, ipa_ref_var_info_summaries, ipa_reference_vars_info_d::local, local_info_obstack, NULL, ipa_reference_global_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_read, and ipa_reference_local_vars_info_d::statics_written.

Referenced by analyze_function().

ipa_init()

static void ipa_init ( void )

static

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

References all_module_statics, BITMAP_ALLOC, bitmap_obstack_initialize(), dump_file, ignore_module_statics, ipa_init_p, ipa_ref_opt_sum_summaries, ipa_ref_var_info_summaries, ipa_reference_vars_map, ipa_reference_vars_uids, local_info_obstack, no_module_statics, NULL, optimization_summary_obstack, reference_vars_to_consider, symtab, varpool_node_hooks, varpool_removal_hook(), and vec_alloc().

Referenced by generate_summary().

ipa_reference_cc_finalize()

void ipa_reference_cc_finalize

(

void

)

Reset all state within ipa-reference.cc so that we can rerun the compiler
within the same process.  For use by toplev::finalize.   

References bitmap_obstack_release(), ipa_init_p, ipa_ref_opt_sum_summaries, ipa_reference_vars_map, NULL, optimization_summary_obstack, symtab, and varpool_node_hooks.

Referenced by toplev::finalize().

ipa_reference_get_read_global()

bitmap ipa_reference_get_read_global

(

struct cgraph_node *

fn

)

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

References AVAIL_AVAILABLE, AVAIL_INTERPOSABLE, AVAIL_NOT_AVAILABLE, current_function_decl, symtab_node::decl, ECF_LEAF, flags_from_decl_or_type(), cgraph_node::function_symbol(), get_reference_optimization_summary(), no_module_statics, NULL, opt_for_fn, and ipa_reference_optimization_summary_d::statics_read.

Referenced by ref_maybe_used_by_call_p_1().

ipa_reference_get_written_global()

bitmap ipa_reference_get_written_global

(

struct cgraph_node *

fn

)

Return a bitmap indexed by ipa_reference_var_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 AVAIL_AVAILABLE, AVAIL_INTERPOSABLE, AVAIL_NOT_AVAILABLE, current_function_decl, symtab_node::decl, ECF_LEAF, flags_from_decl_or_type(), cgraph_node::function_symbol(), get_reference_optimization_summary(), no_module_statics, NULL, opt_for_fn, and ipa_reference_optimization_summary_d::statics_written.

Referenced by call_may_clobber_ref_p_1().

ipa_reference_read_optimization_summary()

static void ipa_reference_read_optimization_summary ( void )

static

Deserialize the ipa info for lto.   

References all_module_statics, BITMAP_ALLOC, bitmap_obstack_initialize(), bitmap_set_bit, symtab_node::dump_asm_name(), dump_file, dyn_cast(), fatal_error(), lto_input_block::file_data, fndecl_name(), gcc_checking_assert, i, input_location, ipa_ref_opt_sum_summaries, ipa_reference_var_get_or_insert_uid(), ipa_reference_var_uid(), ipa_reference_vars_map, ipa_reference_vars_uids, lto_input_block::len, lto_create_simple_input_block(), lto_destroy_simple_input_block(), lto_get_file_decl_data(), lto_input_var_decl_ref(), LTO_section_ipa_reference, lto_symtab_encoder_deref(), no_module_statics, NULL, optimization_summary_obstack, ipa_reference_optimization_summary_d::statics_read, ipa_reference_optimization_summary_d::statics_written, streamer_read_hwi(), streamer_read_uhwi(), symtab, lto_file_decl_data::symtab_node_encoder, varpool_node_hooks, and varpool_removal_hook().

ipa_reference_var_get_or_insert_uid()

int ipa_reference_var_get_or_insert_uid	(	tree	t,
		bool *	existed )

Return ID used by ipa-reference bitmaps.  Create new entry if
T is not in map.  Set EXISTED accordinly   

References symtab_node::get(), ipa_reference_vars_map, ipa_reference_vars_uids, and NULL.

Referenced by analyze_function(), and ipa_reference_read_optimization_summary().

ipa_reference_var_uid()

int ipa_reference_var_uid

(

tree

t

)

Return ID used by ipa-reference bitmaps.  -1 if failed.   

References symtab_node::get(), ipa_reference_vars_map, and NULL.

Referenced by call_may_clobber_ref_p_1(), generate_summary(), ipa_reference_read_optimization_summary(), ipa_reference_write_optimization_summary(), is_proper_for_analysis(), and ref_maybe_used_by_call_p_1().

ipa_reference_write_optimization_summary()

static void ipa_reference_write_optimization_summary ( void )

static

Serialize the ipa info for lto.   

References bitmap_set_bit, count, symtab_node::decl, lto_simple_output_block::decl_state, dyn_cast(), gcc_checking_assert, get_reference_optimization_summary(), i, ipa_reference_var_uid(), ipa_reference_vars_uids, 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, NULL, reference_vars_to_consider, referenced_from_this_partition_p(), ipa_reference_optimization_summary_d::statics_read, ipa_reference_optimization_summary_d::statics_written, stream_out_bitmap(), streamer_write_uhwi_stream(), lto_out_decl_state::symtab_node_encoder, vec_alloc(), vec_free(), and write_node_summary_p().

is_improper()

static bool is_improper ( symtab_node * n, void * v )

static

Hepler for is_proper_for_analysis.   

References symtab_node::decl, DECL_PRESERVE_P, TREE_ADDRESSABLE, TREE_PUBLIC, TREE_READONLY, and TREE_THIS_VOLATILE.

Referenced by is_proper_for_analysis().

is_proper_for_analysis()

static bool is_proper_for_analysis ( tree t )

inlinestatic

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

References bitmap_bit_p, cgraph_node::call_for_symbol_and_aliases(), symtab_node::get(), ignore_module_statics, ipa_reference_var_uid(), is_improper(), and NULL.

Referenced by analyze_function(), and generate_summary().

make_pass_ipa_reference()

ipa_opt_pass_d * make_pass_ipa_reference

(

gcc::context *

ctxt

)

propagate()

static unsigned int propagate ( void )

static

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

References symtab_node::alias, all_module_statics, BITMAP_ALLOC, bitmap_copy(), bitmap_empty_p(), bitmap_equal_p(), bitmap_obstack_release(), cgraph_node::cannot_return_p(), copy_static_var_set(), symtab_node::decl, symtab_node::dump_asm_name(), cgraph_node::dump_cgraph(), dump_file, dump_flags, symtab_node::dump_name(), dump_static_vars_set_to_file(), ECF_CONST, ECF_PURE, flags_from_decl_or_type(), FOR_EACH_DEFINED_FUNCTION, FOR_EACH_VEC_ELT, free(), gcc_assert, gcc_checking_assert, generate_summary(), get_read_write_all_from_node(), get_reference_vars_info(), ipa_reference_vars_info_d::global, i, ignore_edge_p(), cgraph_node::inlined_to, ipa_discover_variable_flags(), ipa_free_postorder_info(), ipa_get_nodes_in_cycle(), ipa_print_order(), ipa_reduced_postorder(), ipa_ref_opt_sum_summaries, ipa_ref_var_info_summaries, ipa_reference_vars_info_d::local, local_info_obstack, no_module_statics, NULL, opt_for_fn, optimization_summary_obstack, symtab_node::order, propagate_bits(), reference_vars_to_consider, ipa_reference_global_vars_info_d::statics_read, ipa_reference_local_vars_info_d::statics_read, ipa_reference_optimization_summary_d::statics_read, ipa_reference_global_vars_info_d::statics_written, ipa_reference_local_vars_info_d::statics_written, ipa_reference_optimization_summary_d::statics_written, symtab, TDF_DETAILS, TODO_remove_functions, union_static_var_sets(), and vec_free().

Referenced by propagate_pseudo_copies().

propagate_bits()

static void propagate_bits ( ipa_reference_global_vars_info_t x_global, struct cgraph_node * x )

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_INTERPOSABLE, cgraph_edge::callee, cgraph_node::callees, cgraph_edge::cannot_lead_to_return_p(), ECF_CONST, ECF_LEAF, ECF_PURE, flags_from_decl_or_type(), cgraph_node::function_symbol(), gcc_unreachable, get_reference_vars_info(), ipa_reference_vars_info_d::global, cgraph_edge::next_callee, opt_for_fn, ipa_reference_global_vars_info_d::statics_read, ipa_reference_global_vars_info_d::statics_written, union_static_var_sets(), and y.

Referenced by propagate().

read_write_all_from_decl()

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_INTERPOSABLE, cgraph_node::cannot_return_p(), symtab_node::decl, dump_file, dump_flags, symtab_node::dump_name(), ECF_CONST, ECF_LEAF, ECF_PURE, flags_from_decl_or_type(), cgraph_node::get_availability(), and TDF_DETAILS.

Referenced by get_read_write_all_from_node().

stream_out_bitmap()

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 all_module_statics, count, lto_simple_output_block::decl_state, EXECUTE_IF_AND_IN_BITMAP, lto_output_var_decl_ref(), lto_simple_output_block::main_stream, and streamer_write_hwi_stream().

Referenced by ipa_reference_write_optimization_summary().

union_static_var_sets()

static bool union_static_var_sets ( bitmap & x, bitmap y )

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(), BITMAP_FREE, bitmap_ior_into(), and y.

Referenced by propagate(), and propagate_bits().

varpool_removal_hook()

static void varpool_removal_hook ( varpool_node * node, void *  )

static

Delete NODE from map.   

References symtab_node::decl, and ipa_reference_vars_map.

Referenced by ipa_init(), and ipa_reference_read_optimization_summary().

write_node_summary_p()

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 symtab_node::definition, EXECUTE_IF_AND_COMPL_IN_BITMAP, get_reference_optimization_summary(), i, cgraph_node::inlined_to, reachable_from_this_partition_p(), referenced_from_this_partition_p(), ipa_reference_optimization_summary_d::statics_read, and ipa_reference_optimization_summary_d::statics_written.

Referenced by ipa_reference_write_optimization_summary().

Variable Documentation

all_module_statics

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 analyze_function(), copy_static_var_set(), dump_static_vars_set_to_file(), generate_summary(), ipa_init(), ipa_reference_read_optimization_summary(), propagate(), propagate_bits(), ipa_ref_opt_summary_t::remove(), stream_out_bitmap(), and union_static_var_sets().

ignore_module_statics

bitmap ignore_module_statics

static

Set of all statics that should be ignored because they are touched by
-fno-ipa-reference code.   

Referenced by generate_summary(), ipa_init(), and is_proper_for_analysis().

ipa_init_p

bool ipa_init_p = false

static

Referenced by ipa_init(), and ipa_reference_cc_finalize().

ipa_ref_opt_sum_summaries

ipa_ref_opt_summary_t* ipa_ref_opt_sum_summaries = NULL

static

Referenced by get_reference_optimization_summary(), ipa_init(), ipa_reference_cc_finalize(), ipa_reference_read_optimization_summary(), and propagate().

ipa_ref_var_info_summaries

ipa_ref_var_info_summary_t* ipa_ref_var_info_summaries = NULL

static

Referenced by get_reference_vars_info(), init_function_info(), ipa_init(), and propagate().

ipa_reference_vars_map

reference_vars_map_t* ipa_reference_vars_map

static

Referenced by ipa_init(), ipa_reference_cc_finalize(), ipa_reference_read_optimization_summary(), ipa_reference_var_get_or_insert_uid(), ipa_reference_var_uid(), and varpool_removal_hook().

ipa_reference_vars_uids

int ipa_reference_vars_uids

static

Referenced by ipa_init(), ipa_reference_read_optimization_summary(), ipa_reference_var_get_or_insert_uid(), and ipa_reference_write_optimization_summary().

local_info_obstack

bitmap_obstack local_info_obstack

static

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

Referenced by init_function_info(), ipa_init(), and propagate().

no_module_statics

bitmap no_module_statics

static

Zero bitmap.   

Referenced by copy_static_var_set(), dump_static_vars_set_to_file(), ipa_init(), ipa_reference_get_read_global(), ipa_reference_get_written_global(), ipa_reference_read_optimization_summary(), propagate(), and ipa_ref_opt_summary_t::remove().

optimization_summary_obstack

bitmap_obstack optimization_summary_obstack

static

Obstack holding global analysis live forever.   

Referenced by ipa_init(), ipa_reference_cc_finalize(), ipa_reference_read_optimization_summary(), and propagate().

reference_vars_to_consider

vec<tree>* reference_vars_to_consider

static

Referenced by analyze_function(), get_static_name(), ipa_init(), ipa_reference_write_optimization_summary(), and propagate().

varpool_node_hooks

varpool_node_hook_list* varpool_node_hooks

Referenced by ipa_init(), ipa_reference_cc_finalize(), and ipa_reference_read_optimization_summary().