cfgbuild.cc File Reference

#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "backend.h"
#include "rtl.h"
#include "cfghooks.h"
#include "memmodel.h"
#include "emit-rtl.h"
#include "cfgrtl.h"
#include "cfganal.h"
#include "cfgbuild.h"
#include "except.h"
#include "stmt.h"

Include dependency graph for cfgbuild.cc:

Macros
#define	STATE(BB)
#define	SET_STATE(BB, STATE)
#define	BLOCK_USED_BY_TABLEJUMP   32
#define	FULL_STATE(BB)

Enumerations
enum	state { BLOCK_NEW = 0 , BLOCK_ORIGINAL , BLOCK_TO_SPLIT }

Functions
static void	make_edges (basic_block, basic_block, int)
static void	make_label_edge (sbitmap, basic_block, rtx, int)
static void	find_bb_boundaries (basic_block)
static void	compute_outgoing_frequencies (basic_block)
bool	inside_basic_block_p (const rtx_insn *insn)
bool	control_flow_insn_p (const rtx_insn *insn)
void	rtl_make_eh_edge (sbitmap edge_cache, basic_block src, rtx insn)
static void	mark_tablejump_edge (rtx label)
static void	purge_dead_tablejump_edges (basic_block bb, rtx_jump_table_data *table)
static void	update_profile_for_new_sub_basic_block (basic_block bb)
void	find_many_sub_basic_blocks (sbitmap blocks)
void	find_sub_basic_blocks (basic_block bb)

Macro Definition Documentation

BLOCK_USED_BY_TABLEJUMP

#define BLOCK_USED_BY_TABLEJUMP   32

Used internally by purge_dead_tablejump_edges, ORed into state.   

Referenced by mark_tablejump_edge(), and purge_dead_tablejump_edges().

FULL_STATE

#define FULL_STATE

(

BB

)

Value:

((size_t) (BB)->aux)

Referenced by mark_tablejump_edge(), and purge_dead_tablejump_edges().

SET_STATE

#define SET_STATE	(		BB,
			STATE )

Value:

((BB)->aux = (void *) (size_t) (STATE))

Referenced by find_many_sub_basic_blocks(), mark_tablejump_edge(), and purge_dead_tablejump_edges().

STATE

#define STATE

(

BB

)

Value:

(enum state) ((size_t) (BB)->aux)

Referenced by find_many_sub_basic_blocks(), and make_edges().

Enumeration Type Documentation

state

enum state

States of basic block as seen by find_many_sub_basic_blocks.   

Enumerator
BLOCK_NEW
BLOCK_ORIGINAL
BLOCK_TO_SPLIT

Function Documentation

compute_outgoing_frequencies()

static void compute_outgoing_frequencies ( basic_block b )

static

Assume that frequency of basic block B is known.  Compute frequencies
and probabilities of outgoing edges.   

References profile_probability::always(), b, BB_END, BRANCH_EDGE, EDGE_COMPLEX, EDGE_COUNT, FALLTHRU_EDGE, find_reg_note(), FOR_EACH_EDGE, profile_probability::from_reg_br_prob_note(), guess_outgoing_edge_probabilities(), NULL, single_succ_edge(), single_succ_p(), and XINT.

Referenced by find_many_sub_basic_blocks(), find_sub_basic_blocks(), and update_profile_for_new_sub_basic_block().

control_flow_insn_p()

bool control_flow_insn_p

(

const rtx_insn *

insn

)

Return true if INSN may cause control flow transfer, so it should be last in
the basic block.   

References can_nonlocal_goto(), can_throw_internal(), cfun, const1_rtx, find_reg_note(), gcc_unreachable, GET_CODE, PATTERN(), SIBLING_CALL_P, and XEXP.

Referenced by add_labels_and_missing_jumps(), dce_process_block(), decompose_multiword_subregs(), emit_common_tails_for_components(), emit_moves(), find_bb_boundaries(), find_moveable_pseudos(), reload_combine(), rtl_verify_bb_insns(), try_head_merge_bb(), unify_moves(), and word_dce_process_block().

find_bb_boundaries()

static void find_bb_boundaries ( basic_block bb )

static

Scan basic block BB for possible BB boundaries inside the block
and create new basic blocks in the progress.   

References BARRIER_P, BB_END, BB_HEAD, cfun, control_flow_insn_p(), basic_block_def::count, debug_insn, DEBUG_INSN_P, delete_insn(), end(), ENTRY_BLOCK_PTR_FOR_FN, gcc_assert, GET_CODE, inside_basic_block_p(), LABEL_ALT_ENTRY_P, LABEL_P, last, make_edge(), NEXT_INSN(), NOTE_P, NULL, PREV_INSN(), prev_nonnote_nondebug_insn_bb(), purge_dead_edges(), purge_dead_tablejump_edges(), remove_edge(), reorder_insns_nobb(), set_block_for_insn(), split_block(), table, tablejump_p(), and profile_count::uninitialized().

Referenced by find_many_sub_basic_blocks(), and find_sub_basic_blocks().

find_many_sub_basic_blocks()

void find_many_sub_basic_blocks

(

sbitmap

blocks

)

Assume that some pass has inserted labels or control flow
instructions within a basic block.  Split basic blocks as needed
and create edges.   

References any_condjump_p(), BB_END, bitmap_bit_p, BLOCK_NEW, BLOCK_ORIGINAL, BLOCK_TO_SPLIT, cfun, compute_outgoing_frequencies(), EDGE_COUNT, EXIT_BLOCK_PTR_FOR_FN, find_bb_boundaries(), FOR_BB_BETWEEN, FOR_EACH_BB_FN, basic_block_def::index, JUMP_P, last_basic_block_for_fn, make_edges(), basic_block_def::next_bb, PROFILE_ABSENT, profile_status_for_fn, SET_STATE, STATE, basic_block_def::succs, update_br_prob_note(), and update_profile_for_new_sub_basic_block().

Referenced by break_superblocks(), lra(), reload(), split_all_insns(), and thread_prologue_and_epilogue_insns().

find_sub_basic_blocks()

void find_sub_basic_blocks

(

basic_block

bb

)

Like find_many_sub_basic_blocks, but look only within BB.   

References cfun, compute_outgoing_frequencies(), find_bb_boundaries(), make_edges(), basic_block_def::next_bb, basic_block_def::prev_bb, PROFILE_ABSENT, profile_status_for_fn, and update_profile_for_new_sub_basic_block().

Referenced by commit_one_edge_insertion(), and thread_prologue_and_epilogue_insns().

inside_basic_block_p()

bool inside_basic_block_p

(

const rtx_insn *

insn

)

Return true if insn is something that should be contained inside basic
block.   

References gcc_unreachable, GET_CODE, JUMP_TABLE_DATA_P, and NEXT_INSN().

Referenced by find_bb_boundaries(), save_point_p(), and scan_trace().

make_edges()

static void make_edges ( basic_block min, basic_block max, int update_p )

static

Control flow graph building code for GNU compiler.
   Copyright (C) 1987-2024 Free Software Foundation, Inc.

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/>.   

Identify the edges going out of basic blocks between MIN and MAX,
inclusive, that have their states set to BLOCK_NEW or
BLOCK_TO_SPLIT.

UPDATE_P should be nonzero if we are updating CFG and zero if we
are building CFG from scratch.   

References ASM_OPERANDS_LABEL, ASM_OPERANDS_LABEL_LENGTH, BB_END, BB_HEAD, bitmap_clear(), bitmap_set_bit, BLOCK_ORIGINAL, cached_make_edge(), can_nonlocal_goto(), cfun, computed_jump_p(), ENTRY_BLOCK_PTR_FOR_FN, EXIT_BLOCK_PTR_FOR_FN, extract_asm_operands(), find_edge(), find_reg_note(), FOR_BB_BETWEEN, FOR_EACH_EDGE, FOR_EACH_VEC_SAFE_ELT, forced_labels, gcc_assert, GET_CODE, GET_NUM_ELEM, i, JUMP_LABEL, LABEL_ALT_ENTRY_P, LABEL_P, label_ref_label(), last_basic_block_for_fn, make_edge(), make_label_edge(), rtx_insn_list::next(), basic_block_def::next_bb, NEXT_INSN(), nonlocal_goto_handler_labels, NOTE_KIND, NOTE_P, NULL, NULL_RTX, PATTERN(), pc_rtx, REG_NOTE_KIND, REG_NOTES, returnjump_p(), rtl_make_eh_edge(), RTVEC_ELT, sbitmap_alloc(), sbitmap_free(), SET_DEST, SET_SRC, SIBLING_CALL_P, single_set(), STATE, basic_block_def::succs, table, tablejump_p(), vec_safe_is_empty(), and XEXP.

make_label_edge()

static void make_label_edge ( sbitmap edge_cache, basic_block src, rtx label, int flags )

static

Create an edge between two basic blocks.  FLAGS are auxiliary information
about the edge that is accumulated between calls.   

Create an edge from a basic block to a label.   

References BLOCK_FOR_INSN(), cached_make_edge(), gcc_assert, INSN_UID(), and LABEL_P.

Referenced by make_edges(), and rtl_make_eh_edge().

mark_tablejump_edge()

static void mark_tablejump_edge ( rtx label )

static

References BLOCK_FOR_INSN(), BLOCK_USED_BY_TABLEJUMP, FULL_STATE, gcc_assert, INSN_UID(), LABEL_P, and SET_STATE.

Referenced by purge_dead_tablejump_edges().

purge_dead_tablejump_edges()

static void purge_dead_tablejump_edges ( basic_block bb, rtx_jump_table_data * table )

static

References BB_END, BLOCK_USED_BY_TABLEJUMP, ei_next(), ei_safe_edge(), ei_start, FULL_STATE, GET_CODE, GET_NUM_ELEM, label_ref_label(), mark_tablejump_edge(), NULL, pc_rtx, remove_edge(), RTVEC_ELT, SET_DEST, SET_SRC, SET_STATE, single_set(), basic_block_def::succs, table, and XEXP.

Referenced by find_bb_boundaries().

rtl_make_eh_edge()

void rtl_make_eh_edge	(	sbitmap	edge_cache,
		basic_block	src,
		rtx	insn )

Create the edges generated by INSN in REGION.   

References CALL_P, gcc_assert, get_eh_landing_pad_from_rtx(), label_rtx(), eh_landing_pad_d::landing_pad, make_label_edge(), NULL, and eh_landing_pad_d::post_landing_pad.

Referenced by decompose_multiword_subregs(), and make_edges().

update_profile_for_new_sub_basic_block()

static void update_profile_for_new_sub_basic_block ( basic_block bb )

static

Update the profile information for BB, which was created by splitting
an RTL block that had a non-final jump.   

References cfun, compute_outgoing_frequencies(), basic_block_def::count, FOR_EACH_EDGE, basic_block_def::preds, PROFILE_GUESSED, profile_status_for_fn, profile_count::uninitialized(), and profile_count::zero().

Referenced by find_many_sub_basic_blocks(), and find_sub_basic_blocks().