#include "config.h"
#include "system.h"
#include "coretypes.h"
#include "timevar.h"
#include "diagnostic-core.h"
#include "ggc-internal.h"
#include "hosthooks.h"
#include "plugin.h"
#include "options.h"

Include dependency graph for ggc-common.cc:

Data Structures
struct	ptr_data
struct	saving_hasher
struct	traversal_state
struct	mmap_info
class	ggc_usage

Macros
#define	INCLUDE_MALLOC_H
#define	POINTER_HASH(x)

Typedefs
typedef const struct ggc_root_tab *	const_ggc_root_tab_t

Functions
static int	compare_ptr_data (const void , const void )
static void	relocate_ptrs (void , void , void *)
static void	write_pch_globals (const struct ggc_root_tab const tab, struct traversal_state *state)
void	ggc_register_root_tab (const struct ggc_root_tab *rt)
static void	ggc_mark_root_tab (const_ggc_root_tab_t rt)
static void	ggc_zero_rtab_roots (const_ggc_root_tab_t rt)
void	ggc_mark_roots (void)
void *	ggc_internal_cleared_alloc (size_t size, void(f)(void ), size_t s, size_t n MEM_STAT_DECL)
void *	ggc_internal_cleared_alloc_no_dtor (size_t size, void(f)(void ), size_t s, size_t n MEM_STAT_DECL)
void *	ggc_realloc (void *x, size_t size MEM_STAT_DECL)
void *	ggc_cleared_alloc_htab_ignore_args (size_t c, size_t n)
void *	ggc_cleared_alloc_ptr_array_two_args (size_t c, size_t n)
void *	ggc_splay_alloc (int sz, void *nl)
void	ggc_splay_dont_free (void x, void nl)
void	ggc_print_common_statistics (FILE stream, ggc_statistics stats)
int	gt_pch_note_object (void obj, void note_ptr_cookie, gt_note_pointers note_ptr_fn, size_t length_override)
void	gt_pch_note_callback (void obj, void base)
void	gt_pch_note_reorder (void obj, void note_ptr_cookie, gt_handle_reorder reorder_fn)
int	ggc_call_count (ptr_data *slot, traversal_state state)
int	ggc_call_alloc (ptr_data *slot, traversal_state state)
static int	compare_ptr (const void p1_p, const void p2_p)
static unsigned char *	read_uleb128 (unsigned char p, size_t val)
static size_t	write_uleb128 (unsigned char *p, size_t val)
void	gt_pch_save (FILE *f)
void	gt_pch_restore (FILE *f)
void *	default_gt_pch_get_address (size_t size, int fd)
int	default_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
size_t	default_gt_pch_alloc_granularity (void)
static double	ggc_rlimit_bound (double limit)
static int	ggc_min_expand_heuristic (void)
static int	ggc_min_heapsize_heuristic (void)
void	init_ggc_heuristics (void)
auto &	ggc_mem_desc ()
void	dump_ggc_loc_statistics ()
void	ggc_record_overhead (size_t allocated, size_t overhead, void *ptr MEM_STAT_DECL)
void	ggc_free_overhead (void *ptr)
void	ggc_prune_overhead_list (void)
void	report_heap_memory_use ()
void	ggc_common_finalize ()

Variables
bool	ggc_protect_identifiers = true
static ggc_statistics *	ggc_stats
static vec< const_ggc_root_tab_t >	extra_root_vec
static hash_table< saving_hasher > *	saving_htab
static vec< void * >	callback_vec
static vec< void * >	reloc_addrs_vec

Macro Definition Documentation

◆ INCLUDE_MALLOC_H

#define INCLUDE_MALLOC_H

Simple garbage collection for the GNU compiler.
   Copyright (C) 1999-2026 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/>.

Generic garbage collection (GC) functions and data, not specific to
any particular GC implementation.

◆ POINTER_HASH

#define POINTER_HASH ( x )

Value:

(hashval_t)((intptr_t)x >> 3)

Referenced by gt_pch_note_callback(), gt_pch_note_object(), gt_pch_note_reorder(), saving_hasher::hash(), relocate_ptrs(), and write_pch_globals().

Typedef Documentation

◆ const_ggc_root_tab_t

typedef const struct ggc_root_tab* const_ggc_root_tab_t

Maintain global roots that are preserved during GC.

This extra vector of dynamically registered root_tab-s is used by
ggc_mark_roots and gives the ability to dynamically add new GGC root
tables, for instance from some plugins; this vector is on the heap
since it is used by GGC internally.

Function Documentation

◆ compare_ptr()

int compare_ptr	(	const void *	p1_p,
		const void *	p2_p )

static

Callback for qsort.

References compare_ptr().

Referenced by compare_ptr(), and gt_pch_save().

◆ compare_ptr_data()

int compare_ptr_data	(	const void *	p1_p,
		const void *	p2_p )

static

Callback for qsort.

References compare_ptr_data(), and ptr_data::new_addr.

Referenced by compare_ptr_data(), and gt_pch_save().

◆ default_gt_pch_alloc_granularity()

size_t default_gt_pch_alloc_granularity ( void )

Default version of HOST_HOOKS_GT_PCH_GET_ADDRESS.   Return the
alignment required for allocating virtual memory. Usually this is the
same as pagesize.

References default_gt_pch_alloc_granularity().

Referenced by default_gt_pch_alloc_granularity().

◆ default_gt_pch_get_address()

void * default_gt_pch_get_address	(	size_t	size,
		int	fd )

Default version of HOST_HOOKS_GT_PCH_GET_ADDRESS when mmap is not present.
Select no address whatsoever, and let gt_pch_save choose what it will with
malloc, presumably.

References default_gt_pch_get_address(), and NULL.

Referenced by default_gt_pch_get_address().

◆ default_gt_pch_use_address()

int default_gt_pch_use_address	(	void *&	base,
		size_t	size,
		int	fd,
		size_t	offset )

Default version of HOST_HOOKS_GT_PCH_USE_ADDRESS when mmap is not present.
Allocate SIZE bytes with malloc.  Return 0 if the address we got is the
same as base, indicating that the memory has been allocated but needs to
be read in from the file.  Return -1 if the address differs, to relocation
of the PCH file would be required.

References default_gt_pch_use_address().

Referenced by default_gt_pch_use_address().

◆ dump_ggc_loc_statistics()

void dump_ggc_loc_statistics ( )

Dump per-site memory statistics.

References dump_ggc_loc_statistics(), GGC_COLLECT_FORCE, ggc_mem_desc(), and GGC_ORIGIN.

Referenced by dump_ggc_loc_statistics(), dump_memory_report(), and ggc_realloc().

◆ ggc_call_alloc()

int ggc_call_alloc	(	ptr_data **	slot,
		traversal_state *	state )

References ggc_call_alloc(), ggc_pch_alloc_object(), ptr_data::new_addr, ptr_data::obj, and ptr_data::size.

Referenced by ggc_call_alloc(), and gt_pch_save().

◆ ggc_call_count()

int ggc_call_count	(	ptr_data **	slot,
		traversal_state *	state )

Callbacks for htab_traverse.

References ggc_call_count(), ggc_pch_count_object(), ptr_data::obj, and ptr_data::size.

Referenced by ggc_call_count(), and gt_pch_save().

◆ ggc_cleared_alloc_htab_ignore_args()

void * ggc_cleared_alloc_htab_ignore_args	(	size_t	c,
		size_t	n )

References gcc_assert, ggc_cleared_alloc(), and ggc_cleared_alloc_htab_ignore_args().

Referenced by ggc_cleared_alloc_htab_ignore_args().

◆ ggc_cleared_alloc_ptr_array_two_args()

void * ggc_cleared_alloc_ptr_array_two_args	(	size_t	c,
		size_t	n )

TODO: once we actually use type information in GGC, create a new tag
gt_gcc_ptr_array and use it for pointer arrays.

References gcc_assert, ggc_cleared_alloc_ptr_array_two_args(), and ggc_cleared_vec_alloc().

Referenced by ggc_cleared_alloc_ptr_array_two_args().

◆ ggc_common_finalize()

void ggc_common_finalize ( )

Forcibly clear all GTY roots.

References ggc_root_tab::base, ggc_common_finalize(), ggc_zero_rtab_roots(), gt_ggc_deletable_rtab, gt_ggc_rtab, gt_pch_scalar_rtab, ggc_root_tab::nelt, NULL, and ggc_root_tab::stride.

Referenced by toplev::finalize(), and ggc_common_finalize().

◆ ggc_free_overhead()

void ggc_free_overhead ( void * ptr )

Notice that the pointer has been freed.

References ggc_free_overhead(), and ggc_mem_desc().

Referenced by ggc_free(), ggc_free_overhead(), and ggc_record_overhead().

◆ ggc_internal_cleared_alloc()

void * ggc_internal_cleared_alloc	(	size_t	size,
		void(*	f )(void *),
		size_t	s,
		size_t n	MEM_STAT_DECL )

Allocate a block of memory, then clear it.

References ggc_internal_alloc(), ggc_internal_cleared_alloc(), MEM_STAT_DECL, and PASS_MEM_STAT.

◆ ggc_internal_cleared_alloc_no_dtor()

void * ggc_internal_cleared_alloc_no_dtor	(	size_t	size,
		void(*	f )(void *),
		size_t	s,
		size_t n	MEM_STAT_DECL )

References ggc_internal_cleared_alloc(), ggc_internal_cleared_alloc_no_dtor(), MEM_STAT_DECL, and PASS_MEM_STAT.

◆ ggc_mark_root_tab()

void ggc_mark_root_tab ( const_ggc_root_tab_t rt )

static

Mark all the roots in the table RT.

References ggc_root_tab::base, ggc_root_tab::cb, ggc_mark_root_tab(), i, ggc_root_tab::nelt, NULL, and ggc_root_tab::stride.

Referenced by ggc_mark_root_tab(), and ggc_mark_roots().

◆ ggc_mark_roots()

void ggc_mark_roots ( void )

Iterate through all registered roots and mark each element.

Garbage collection for the GNU compiler.  Internal definitions
   for ggc-*.c and stringpool.cc.

   Copyright (C) 2009-2026 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/>.

Call ggc_set_mark on all the roots.

References ggc_root_tab::base, extra_root_vec, FOR_EACH_VEC_ELT, ggc_mark_root_tab(), ggc_mark_roots(), ggc_mark_stringpool(), ggc_protect_identifiers, ggc_purge_stringpool(), gt_clear_caches(), gt_ggc_deletable_rtab, gt_ggc_rtab, i, invoke_plugin_callbacks(), ggc_root_tab::nelt, NULL, and ggc_root_tab::stride.

Referenced by ggc_collect(), and ggc_mark_roots().

◆ ggc_mem_desc()

auto & ggc_mem_desc ( )

inline

GCC memory description.

References ggc_mem_desc(), and mem_alloc_description< T >::instance().

Referenced by dump_ggc_loc_statistics(), ggc_free_overhead(), ggc_mem_desc(), ggc_prune_overhead_list(), and ggc_record_overhead().

◆ ggc_min_expand_heuristic()

int ggc_min_expand_heuristic ( void )

static

Heuristic to set a default for GGC_MIN_EXPAND.

References ggc_min_expand_heuristic(), ggc_rlimit_bound(), MIN, and ONE_G.

Referenced by ggc_min_expand_heuristic(), ggc_min_heapsize_heuristic(), and init_ggc_heuristics().

◆ ggc_min_heapsize_heuristic()

int ggc_min_heapsize_heuristic ( void )

static

Heuristic to set a default for GGC_MIN_HEAPSIZE.

References ggc_min_expand_heuristic(), ggc_min_heapsize_heuristic(), ggc_rlimit_bound(), MAX, MIN, and ONE_K.

Referenced by ggc_min_heapsize_heuristic(), and init_ggc_heuristics().

◆ ggc_print_common_statistics()

void ggc_print_common_statistics	(	FILE *	stream,
		ggc_statistics *	stats )

Used by the various collectors to gather and print statistics that
do not depend on the collector in use.

References ggc_print_common_statistics(), ggc_stats, and NULL.

Referenced by ggc_print_common_statistics(), and ggc_print_statistics().

◆ ggc_prune_overhead_list()

void ggc_prune_overhead_list ( void )

After live values has been marked, walk all recorded pointers and see if
they are still live.

References ggc_marked_p(), ggc_mem_desc(), and ggc_prune_overhead_list().

Referenced by ggc_collect(), ggc_prune_overhead_list(), and ggc_record_overhead().

◆ ggc_realloc()

void * ggc_realloc	(	void *	x,
		size_t size	MEM_STAT_DECL )

Resize a block of memory, possibly re-allocating it.

References ggc_free(), ggc_get_size(), ggc_internal_alloc(), ggc_realloc(), MEM_STAT_DECL, NULL, PASS_MEM_STAT, r, and VALGRIND_DISCARD.

Referenced by ggc_realloc(), ggc_realloc(), ggc_realloc(), grow_tree_vec(), and realloc_for_line_map().

◆ ggc_record_overhead()

void ggc_record_overhead	(	size_t	allocated,
		size_t	overhead,
		void *ptr	MEM_STAT_DECL )

Record ALLOCATED and OVERHEAD bytes to descriptor NAME:LINE (FUNCTION).

References FINAL_PASS_MEM_STAT, ggc_mem_desc(), GGC_ORIGIN, ggc_record_overhead(), MEM_STAT_DECL, and ggc_usage::register_overhead().

Referenced by ggc_internal_alloc(), ggc_record_overhead(), and ggc_record_overhead().

◆ ggc_register_root_tab()

void ggc_register_root_tab ( const struct ggc_root_tab * rt )

Dynamically register a new GGC root table RT. This is useful for
plugins.

Register an additional root table.  This can be useful for some
plugins.  Does nothing if the passed pointer is NULL.

References extra_root_vec, and ggc_register_root_tab().

Referenced by ggc_register_root_tab(), and register_callback().

◆ ggc_rlimit_bound()

double ggc_rlimit_bound ( double limit )

static

Modify the bound based on rlimits.

References ggc_rlimit_bound(), and ONE_M.

Referenced by ggc_min_expand_heuristic(), ggc_min_heapsize_heuristic(), and ggc_rlimit_bound().

◆ ggc_splay_alloc()

void * ggc_splay_alloc	(	int	sz,
		void *	nl )

These are for splay_tree_new_ggc.

References gcc_assert, ggc_internal_alloc(), and ggc_splay_alloc().

Referenced by ggc_splay_alloc().

◆ ggc_splay_dont_free()

void ggc_splay_dont_free	(	void *	x,
		void *	nl )

References gcc_assert, and ggc_splay_dont_free().

Referenced by ggc_splay_dont_free().

◆ ggc_zero_rtab_roots()

void ggc_zero_rtab_roots ( const_ggc_root_tab_t rt )

static

Zero out all the roots in the table RT.

References ggc_root_tab::base, ggc_zero_rtab_roots(), i, ggc_root_tab::nelt, NULL, and ggc_root_tab::stride.

Referenced by ggc_common_finalize(), and ggc_zero_rtab_roots().

◆ gt_pch_note_callback()

void gt_pch_note_callback	(	void *	obj,
		void *	base )

Register address of a callback pointer.

Used by the gt_pch_p_* routines.  Register address of a callback
pointer.

References callback_vec, gcc_assert, gt_pch_note_callback(), NULL, ptr_data::obj, POINTER_HASH, and saving_htab.

Referenced by gt_pch_note_callback().

◆ gt_pch_note_object()

int gt_pch_note_object	(	void *	obj,
		void *	note_ptr_cookie,
		gt_note_pointers	note_ptr_fn,
		size_t	length_override = (size_t) -1 )

Register an object in the hash table.

Used by the gt_pch_n_* routines.  Register an object in the hash table.

References gcc_assert, ggc_get_size(), gt_pch_note_object(), gt_pch_p_S(), ptr_data::note_ptr_cookie, ptr_data::note_ptr_fn, NULL, ptr_data::obj, POINTER_HASH, and saving_htab.

Referenced by gt_pch_n_S(), gt_pch_n_S2(), gt_pch_note_object(), and gt_pch_nx().

◆ gt_pch_note_reorder()

void gt_pch_note_reorder	(	void *	obj,
		void *	note_ptr_cookie,
		gt_handle_reorder	reorder_fn )

Register an object in the hash table.

Used by the gt_pch_n_* routines.  Register that an object has a reorder
function.

References gcc_assert, gcc_checking_assert, gt_pch_note_reorder(), gt_pch_p_S(), ptr_data::note_ptr_cookie, NULL, ptr_data::obj, POINTER_HASH, ptr_data::reorder_fn, and saving_htab.

Referenced by gt_pch_note_reorder().

◆ gt_pch_restore()

void gt_pch_restore ( FILE * f )

Read the state of the compiler back in from F.

Read objects previously saved with gt_pch_save from F.

References ggc_root_tab::base, fatal_error(), gcc_assert, ggc_pch_read(), gt_ggc_deletable_rtab, gt_ggc_rtab, gt_pch_restore(), gt_pch_restore_stringpool(), gt_pch_save(), gt_pch_scalar_rtab, host_hooks::gt_pch_use_address, i, input_location, line_table, MIN, ggc_root_tab::nelt, NULL, mmap_info::offset, mmap_info::preferred_base, read_uleb128(), SEEK_CUR, SEEK_SET, mmap_info::size, sorry_at(), and ggc_root_tab::stride.

Referenced by gt_pch_restore().

◆ gt_pch_save()

void gt_pch_save ( FILE * f )

Write out the state of the compiler to F.

Write out all GCed objects to F.

References ggc_root_tab::base, callback_vec, compare_ptr(), compare_ptr_data(), fatal_error(), gcc_assert, gcc_checking_assert, ggc_call_alloc(), ggc_call_count(), ggc_pch_finish(), ggc_pch_prepare_write(), ggc_pch_this_base(), ggc_pch_total_size(), ggc_pch_write_object(), gt_ggc_rtab, host_hooks::gt_pch_alloc_granularity, gt_pch_fixup_stringpool(), host_hooks::gt_pch_get_address, gt_pch_p_S(), gt_pch_save(), gt_pch_save_stringpool(), gt_pch_scalar_rtab, hash_table< Descriptor, Lazy, Allocator >::hash_table(), i, init_ggc_pch(), input_location, ggc_root_tab::nelt, NULL, mmap_info::offset, ggc_root_tab::pchw, mmap_info::preferred_base, qsort, reloc_addrs_vec, relocate_ptrs(), saving_htab, SEEK_SET, mmap_info::size, ggc_root_tab::stride, timevar_pop(), timevar_push(), UNLIKELY, VALGRIND_DISCARD, vNULL, write_pch_globals(), and write_uleb128().

Referenced by gt_pch_restore(), and gt_pch_save().

◆ init_ggc_heuristics()

void init_ggc_heuristics ( void )

Heuristics.

References ggc_min_expand_heuristic(), ggc_min_heapsize_heuristic(), and init_ggc_heuristics().

Referenced by init_ggc_heuristics(), and toplev::main().

◆ read_uleb128()

unsigned char * read_uleb128	(	unsigned char *	p,
		size_t *	val )

static

Decode one uleb128 from P, return first byte after it, store
decoded value into *VAL.

References read_uleb128().

Referenced by gt_pch_restore(), and read_uleb128().

◆ relocate_ptrs()

void relocate_ptrs	(	void *	ptr_p,
		void *	real_ptr_p,
		void *	state_p )

static

Callbacks for note_ptr_fn.

References gcc_assert, ptr_data::new_addr, NULL, POINTER_HASH, reloc_addrs_vec, relocate_ptrs(), and saving_htab.

Referenced by gt_pch_save(), and relocate_ptrs().

◆ report_heap_memory_use()

void report_heap_memory_use ( void )

Print memory used by heap if this info is available.

Report current heap memory use to stderr.

References PRsa, report_heap_memory_use(), and SIZE_AMOUNT.

Referenced by execute_one_pass(), ipa_read_optimization_summaries_1(), ipa_read_summaries_1(), and report_heap_memory_use().

◆ write_pch_globals()

void write_pch_globals	(	const struct ggc_root_tab const	tab,
		struct traversal_state *	state )

static

Write out, after relocation, the pointers in TAB.

References ggc_root_tab::base, fatal_error(), i, input_location, ggc_root_tab::nelt, ptr_data::new_addr, NULL, POINTER_HASH, saving_htab, ggc_root_tab::stride, and write_pch_globals().

Referenced by gt_pch_save(), and write_pch_globals().

◆ write_uleb128()

size_t write_uleb128	(	unsigned char *	p,
		size_t	val )

static

Store VAL as uleb128 at P, return length in bytes.

References write_uleb128().

Referenced by gt_pch_save(), and write_uleb128().

Variable Documentation

◆ callback_vec

vec<void *> callback_vec

static

Referenced by gt_pch_note_callback(), and gt_pch_save().

◆ extra_root_vec

vec<const_ggc_root_tab_t> extra_root_vec

static

Referenced by ggc_mark_roots(), and ggc_register_root_tab().

◆ ggc_protect_identifiers

bool ggc_protect_identifiers = true

When true, protect the contents of the identifier hash table.

When true, identifier nodes are considered as GC roots.  When
false, identifier nodes are treated like any other GC-allocated
object, and the identifier hash table is treated as a weak
hash.

Referenced by compile_file(), do_compile(), and ggc_mark_roots().

◆ ggc_stats

ggc_statistics* ggc_stats

static

Statistics about the allocation.

Referenced by ggc_print_common_statistics().

◆ reloc_addrs_vec

vec<void *> reloc_addrs_vec

static

Referenced by gt_pch_save(), and relocate_ptrs().

◆ saving_htab

hash_table<saving_hasher>* saving_htab

static

Referenced by gt_pch_note_callback(), gt_pch_note_object(), gt_pch_note_reorder(), gt_pch_save(), relocate_ptrs(), and write_pch_globals().

Data Structures

Macros

Typedefs

Functions

Variables

Macro Definition Documentation

◆ INCLUDE_MALLOC_H

◆ POINTER_HASH

Typedef Documentation

◆ const_ggc_root_tab_t

Function Documentation

◆ compare_ptr()

◆ compare_ptr_data()

◆ default_gt_pch_alloc_granularity()

◆ default_gt_pch_get_address()

◆ default_gt_pch_use_address()

◆ dump_ggc_loc_statistics()

◆ ggc_call_alloc()

◆ ggc_call_count()

◆ ggc_cleared_alloc_htab_ignore_args()

◆ ggc_cleared_alloc_ptr_array_two_args()

◆ ggc_common_finalize()

◆ ggc_free_overhead()

◆ ggc_internal_cleared_alloc()

◆ ggc_internal_cleared_alloc_no_dtor()

◆ ggc_mark_root_tab()

◆ ggc_mark_roots()

◆ ggc_mem_desc()

◆ ggc_min_expand_heuristic()

◆ ggc_min_heapsize_heuristic()

◆ ggc_print_common_statistics()

◆ ggc_prune_overhead_list()

◆ ggc_realloc()

◆ ggc_record_overhead()

◆ ggc_register_root_tab()

◆ ggc_rlimit_bound()

◆ ggc_splay_alloc()

◆ ggc_splay_dont_free()

◆ ggc_zero_rtab_roots()

◆ gt_pch_note_callback()

◆ gt_pch_note_object()

◆ gt_pch_note_reorder()

◆ gt_pch_restore()

◆ gt_pch_save()

◆ init_ggc_heuristics()

◆ read_uleb128()

◆ relocate_ptrs()

◆ report_heap_memory_use()

◆ write_pch_globals()

◆ write_uleb128()

Variable Documentation

◆ callback_vec

◆ extra_root_vec

◆ ggc_protect_identifiers

◆ ggc_stats

◆ reloc_addrs_vec

◆ saving_htab