/* "Bag-of-pages" garbage collector for the GNU compiler.
- Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+ Copyright (C) 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007
+ 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 2, or (at your option) any later
+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
for more details.
You should have received a copy of the GNU General Public License
-along with GCC; see the file COPYING. If not, write to the Free
-Software Foundation, 59 Temple Place - Suite 330, Boston, MA
-02111-1307, USA. */
+along with GCC; see the file COPYING3. If not see
+<http://www.gnu.org/licenses/>. */
#include "config.h"
#include "system.h"
#include "rtl.h"
#include "tm_p.h"
#include "toplev.h"
-#include "varray.h"
#include "flags.h"
#include "ggc.h"
#include "timevar.h"
#include "params.h"
-#ifdef ENABLE_VALGRIND_CHECKING
-# ifdef HAVE_MEMCHECK_H
-# include <memcheck.h>
-# else
-# include <valgrind.h>
-# endif
-#else
-/* Avoid #ifdef:s when we can help it. */
-#define VALGRIND_DISCARD(x)
-#endif
+#include "tree-flow.h"
/* Prefer MAP_ANON(YMOUS) to /dev/zero, since we don't need to keep a
file open. Prefer either to valloc. */
#define USING_MALLOC_PAGE_GROUPS
#endif
-/* Stategy:
+/* Strategy:
This garbage-collecting allocator allocates objects on one of a set
of pages. Each page can allocate objects of a single size only;
#define NUM_EXTRA_ORDERS ARRAY_SIZE (extra_order_size_table)
#define RTL_SIZE(NSLOTS) \
- (sizeof (struct rtx_def) + ((NSLOTS) - 1) * sizeof (rtunion))
+ (RTX_HDR_SIZE + (NSLOTS) * sizeof (rtunion))
+
+#define TREE_EXP_SIZE(OPS) \
+ (sizeof (struct tree_exp) + ((OPS) - 1) * sizeof (tree))
/* The Ith entry is the maximum size of an object to be stored in the
Ith extra order. Adding a new entry to this array is the *only*
thing you need to do to add a new special allocation size. */
static const size_t extra_order_size_table[] = {
- sizeof (struct tree_decl),
+ sizeof (struct stmt_ann_d),
+ sizeof (struct var_ann_d),
+ sizeof (struct tree_decl_non_common),
+ sizeof (struct tree_field_decl),
+ sizeof (struct tree_parm_decl),
+ sizeof (struct tree_var_decl),
sizeof (struct tree_list),
- RTL_SIZE (2), /* REG, MEM, PLUS, etc. */
- RTL_SIZE (10), /* INSN, CALL_INSN, JUMP_INSN */
+ sizeof (struct tree_ssa_name),
+ sizeof (struct function),
+ sizeof (struct basic_block_def),
+ sizeof (bitmap_element),
+ sizeof (bitmap_head),
+ /* PHI nodes with one to three arguments are already covered by the
+ above sizes. */
+ sizeof (struct tree_phi_node) + sizeof (struct phi_arg_d) * 3,
+ TREE_EXP_SIZE (2),
+ RTL_SIZE (2), /* MEM, PLUS, etc. */
+ RTL_SIZE (9), /* INSN */
};
/* The total number of orders. */
char c;
union {
HOST_WIDEST_INT i;
-#ifdef HAVE_LONG_DOUBLE
long double d;
-#else
- double d;
-#endif
} u;
};
static struct
{
- unsigned int mult;
+ size_t mult;
unsigned int shift;
}
inverse_table[NUM_ORDERS];
this is the last page-entry. */
struct page_entry *next;
+ /* The previous page-entry with objects of the same size, or NULL if
+ this is the first page-entry. The PREV pointer exists solely to
+ keep the cost of ggc_free manageable. */
+ struct page_entry *prev;
+
/* The number of bytes allocated. (This will always be a multiple
of the host system page size.) */
size_t bytes;
struct page_group *group;
#endif
- /* Saved in-use bit vector for pages that aren't in the topmost
- context during collection. */
- unsigned long *save_in_use_p;
+ /* This is the index in the by_depth varray where this page table
+ can be found. */
+ unsigned long index_by_depth;
/* Context depth of this page. */
unsigned short context_depth;
/* The file descriptor for debugging output. */
FILE *debug_file;
+
+ /* Current number of elements in use in depth below. */
+ unsigned int depth_in_use;
+
+ /* Maximum number of elements that can be used before resizing. */
+ unsigned int depth_max;
+
+ /* Each element of this arry is an index in by_depth where the given
+ depth starts. This structure is indexed by that given depth we
+ are interested in. */
+ unsigned int *depth;
+
+ /* Current number of elements in use in by_depth below. */
+ unsigned int by_depth_in_use;
+
+ /* Maximum number of elements that can be used before resizing. */
+ unsigned int by_depth_max;
+
+ /* Each element of this array is a pointer to a page_entry, all
+ page_entries can be found in here by increasing depth.
+ index_by_depth in the page_entry is the index into this data
+ structure where that page_entry can be found. This is used to
+ speed up finding all page_entries at a particular depth. */
+ page_entry **by_depth;
+
+ /* Each element is a pointer to the saved in_use_p bits, if any,
+ zero otherwise. We allocate them all together, to enable a
+ better runtime data access pattern. */
+ unsigned long **save_in_use;
+
+#ifdef ENABLE_GC_ALWAYS_COLLECT
+ /* List of free objects to be verified as actually free on the
+ next collection. */
+ struct free_object
+ {
+ void *object;
+ struct free_object *next;
+ } *free_object_list;
+#endif
+
+#ifdef GATHER_STATISTICS
+ struct
+ {
+ /* Total memory allocated with ggc_alloc. */
+ unsigned long long total_allocated;
+ /* Total overhead for memory to be allocated with ggc_alloc. */
+ unsigned long long total_overhead;
+
+ /* Total allocations and overhead for sizes less than 32, 64 and 128.
+ These sizes are interesting because they are typical cache line
+ sizes. */
+
+ unsigned long long total_allocated_under32;
+ unsigned long long total_overhead_under32;
+
+ unsigned long long total_allocated_under64;
+ unsigned long long total_overhead_under64;
+
+ unsigned long long total_allocated_under128;
+ unsigned long long total_overhead_under128;
+
+ /* The allocations for each of the allocation orders. */
+ unsigned long long total_allocated_per_order[NUM_ORDERS];
+
+ /* The overhead for each of the allocation orders. */
+ unsigned long long total_overhead_per_order[NUM_ORDERS];
+ } stats;
+#endif
} G;
/* The size in bytes required to maintain a bitmap for the objects
/* Allocate pages in chunks of this size, to throttle calls to memory
allocation routines. The first page is used, the rest go onto the
free list. This cannot be larger than HOST_BITS_PER_INT for the
- in_use bitmask for page_group. */
-#define GGC_QUIRE_SIZE 16
+ in_use bitmask for page_group. Hosts that need a different value
+ can override this by defining GGC_QUIRE_SIZE explicitly. */
+#ifndef GGC_QUIRE_SIZE
+# ifdef USING_MMAP
+# define GGC_QUIRE_SIZE 256
+# else
+# define GGC_QUIRE_SIZE 16
+# endif
+#endif
+
+/* Initial guess as to how many page table entries we might need. */
+#define INITIAL_PTE_COUNT 128
\f
-static int ggc_allocated_p PARAMS ((const void *));
-static page_entry *lookup_page_table_entry PARAMS ((const void *));
-static void set_page_table_entry PARAMS ((void *, page_entry *));
+static int ggc_allocated_p (const void *);
+static page_entry *lookup_page_table_entry (const void *);
+static void set_page_table_entry (void *, page_entry *);
#ifdef USING_MMAP
-static char *alloc_anon PARAMS ((char *, size_t));
+static char *alloc_anon (char *, size_t);
#endif
#ifdef USING_MALLOC_PAGE_GROUPS
-static size_t page_group_index PARAMS ((char *, char *));
-static void set_page_group_in_use PARAMS ((page_group *, char *));
-static void clear_page_group_in_use PARAMS ((page_group *, char *));
+static size_t page_group_index (char *, char *);
+static void set_page_group_in_use (page_group *, char *);
+static void clear_page_group_in_use (page_group *, char *);
#endif
-static struct page_entry * alloc_page PARAMS ((unsigned));
-static void free_page PARAMS ((struct page_entry *));
-static void release_pages PARAMS ((void));
-static void clear_marks PARAMS ((void));
-static void sweep_pages PARAMS ((void));
-static void ggc_recalculate_in_use_p PARAMS ((page_entry *));
-static void compute_inverse PARAMS ((unsigned));
+static struct page_entry * alloc_page (unsigned);
+static void free_page (struct page_entry *);
+static void release_pages (void);
+static void clear_marks (void);
+static void sweep_pages (void);
+static void ggc_recalculate_in_use_p (page_entry *);
+static void compute_inverse (unsigned);
+static inline void adjust_depth (void);
+static void move_ptes_to_front (int, int);
+
+void debug_print_page_list (int);
+static void push_depth (unsigned int);
+static void push_by_depth (page_entry *, unsigned long *);
+
+/* Push an entry onto G.depth. */
+
+inline static void
+push_depth (unsigned int i)
+{
+ if (G.depth_in_use >= G.depth_max)
+ {
+ G.depth_max *= 2;
+ G.depth = xrealloc (G.depth, G.depth_max * sizeof (unsigned int));
+ }
+ G.depth[G.depth_in_use++] = i;
+}
-#ifdef ENABLE_GC_CHECKING
-static void poison_pages PARAMS ((void));
+/* Push an entry onto G.by_depth and G.save_in_use. */
+
+inline static void
+push_by_depth (page_entry *p, unsigned long *s)
+{
+ if (G.by_depth_in_use >= G.by_depth_max)
+ {
+ G.by_depth_max *= 2;
+ G.by_depth = xrealloc (G.by_depth,
+ G.by_depth_max * sizeof (page_entry *));
+ G.save_in_use = xrealloc (G.save_in_use,
+ G.by_depth_max * sizeof (unsigned long *));
+ }
+ G.by_depth[G.by_depth_in_use] = p;
+ G.save_in_use[G.by_depth_in_use++] = s;
+}
+
+#if (GCC_VERSION < 3001)
+#define prefetch(X) ((void) X)
+#else
+#define prefetch(X) __builtin_prefetch (X)
#endif
-void debug_print_page_list PARAMS ((int));
-\f
+#define save_in_use_p_i(__i) \
+ (G.save_in_use[__i])
+#define save_in_use_p(__p) \
+ (save_in_use_p_i (__p->index_by_depth))
+
/* Returns nonzero if P was allocated in GC'able memory. */
static inline int
-ggc_allocated_p (p)
- const void *p;
+ggc_allocated_p (const void *p)
{
page_entry ***base;
size_t L1, L2;
Die (probably) if the object wasn't allocated via GC. */
static inline page_entry *
-lookup_page_table_entry(p)
- const void *p;
+lookup_page_table_entry (const void *p)
{
page_entry ***base;
size_t L1, L2;
/* Set the page table entry for a page. */
static void
-set_page_table_entry(p, entry)
- void *p;
- page_entry *entry;
+set_page_table_entry (void *p, page_entry *entry)
{
page_entry ***base;
size_t L1, L2;
goto found;
/* Not found -- allocate a new table. */
- table = (page_table) xcalloc (1, sizeof(*table));
+ table = xcalloc (1, sizeof(*table));
table->next = G.lookup;
table->high_bits = high_bits;
G.lookup = table;
L2 = LOOKUP_L2 (p);
if (base[L1] == NULL)
- base[L1] = (page_entry **) xcalloc (PAGE_L2_SIZE, sizeof (page_entry *));
+ base[L1] = XCNEWVEC (page_entry *, PAGE_L2_SIZE);
base[L1][L2] = entry;
}
/* Prints the page-entry for object size ORDER, for debugging. */
void
-debug_print_page_list (order)
- int order;
+debug_print_page_list (int order)
{
page_entry *p;
- printf ("Head=%p, Tail=%p:\n", (PTR) G.pages[order],
- (PTR) G.page_tails[order]);
+ printf ("Head=%p, Tail=%p:\n", (void *) G.pages[order],
+ (void *) G.page_tails[order]);
p = G.pages[order];
while (p != NULL)
{
- printf ("%p(%1d|%3d) -> ", (PTR) p, p->context_depth,
+ printf ("%p(%1d|%3d) -> ", (void *) p, p->context_depth,
p->num_free_objects);
p = p->next;
}
compile error unless exactly one of the HAVE_* is defined. */
static inline char *
-alloc_anon (pref, size)
- char *pref ATTRIBUTE_UNUSED;
- size_t size;
+alloc_anon (char *pref ATTRIBUTE_UNUSED, size_t size)
{
#ifdef HAVE_MMAP_ANON
- char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
+ char *page = mmap (pref, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
#endif
#ifdef HAVE_MMAP_DEV_ZERO
- char *page = (char *) mmap (pref, size, PROT_READ | PROT_WRITE,
- MAP_PRIVATE, G.dev_zero_fd, 0);
+ char *page = mmap (pref, size, PROT_READ | PROT_WRITE,
+ MAP_PRIVATE, G.dev_zero_fd, 0);
#endif
if (page == (char *) MAP_FAILED)
/* Pretend we don't have access to the allocated pages. We'll enable
access to smaller pieces of the area in ggc_alloc. Discard the
handle to avoid handle leak. */
- VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS (page, size));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (page, size));
return page;
}
/* Compute the index for this page into the page group. */
static inline size_t
-page_group_index (allocation, page)
- char *allocation, *page;
+page_group_index (char *allocation, char *page)
{
return (size_t) (page - allocation) >> G.lg_pagesize;
}
/* Set and clear the in_use bit for this page in the page group. */
static inline void
-set_page_group_in_use (group, page)
- page_group *group;
- char *page;
+set_page_group_in_use (page_group *group, char *page)
{
group->in_use |= 1 << page_group_index (group->allocation, page);
}
static inline void
-clear_page_group_in_use (group, page)
- page_group *group;
- char *page;
+clear_page_group_in_use (page_group *group, char *page)
{
group->in_use &= ~(1 << page_group_index (group->allocation, page));
}
appropriate page_table list. */
static inline struct page_entry *
-alloc_page (order)
- unsigned order;
+alloc_page (unsigned order)
{
struct page_entry *entry, *p, **pp;
char *page;
memory order. */
for (i = GGC_QUIRE_SIZE - 1; i >= 1; i--)
{
- e = (struct page_entry *) xcalloc (1, page_entry_size);
+ e = xcalloc (1, page_entry_size);
e->order = order;
e->bytes = G.pagesize;
e->page = page + (i << G.lg_pagesize);
enda -= G.pagesize;
tail_slop += G.pagesize;
}
- if (tail_slop < sizeof (page_group))
- abort ();
+ gcc_assert (tail_slop >= sizeof (page_group));
group = (page_group *)enda;
tail_slop -= sizeof (page_group);
}
struct page_entry *e, *f = G.free_pages;
for (a = enda - G.pagesize; a != page; a -= G.pagesize)
{
- e = (struct page_entry *) xcalloc (1, page_entry_size);
+ e = xcalloc (1, page_entry_size);
e->order = order;
e->bytes = G.pagesize;
e->page = a;
#endif
if (entry == NULL)
- entry = (struct page_entry *) xcalloc (1, page_entry_size);
+ entry = xcalloc (1, page_entry_size);
entry->bytes = entry_size;
entry->page = page;
if (GGC_DEBUG_LEVEL >= 2)
fprintf (G.debug_file,
"Allocating page at %p, object size=%lu, data %p-%p\n",
- (PTR) entry, (unsigned long) OBJECT_SIZE (order), page,
+ (void *) entry, (unsigned long) OBJECT_SIZE (order), page,
page + entry_size - 1);
return entry;
}
-/* For a page that is no longer needed, put it on the free page list. */
+/* Adjust the size of G.depth so that no index greater than the one
+ used by the top of the G.by_depth is used. */
static inline void
-free_page (entry)
- page_entry *entry;
+adjust_depth (void)
+{
+ page_entry *top;
+
+ if (G.by_depth_in_use)
+ {
+ top = G.by_depth[G.by_depth_in_use-1];
+
+ /* Peel back indices in depth that index into by_depth, so that
+ as new elements are added to by_depth, we note the indices
+ of those elements, if they are for new context depths. */
+ while (G.depth_in_use > (size_t)top->context_depth+1)
+ --G.depth_in_use;
+ }
+}
+
+/* For a page that is no longer needed, put it on the free page list. */
+
+static void
+free_page (page_entry *entry)
{
if (GGC_DEBUG_LEVEL >= 2)
fprintf (G.debug_file,
- "Deallocating page at %p, data %p-%p\n", (PTR) entry,
+ "Deallocating page at %p, data %p-%p\n", (void *) entry,
entry->page, entry->page + entry->bytes - 1);
/* Mark the page as inaccessible. Discard the handle to avoid handle
leak. */
- VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS (entry->page, entry->bytes));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (entry->page, entry->bytes));
set_page_table_entry (entry->page, NULL);
clear_page_group_in_use (entry->group, entry->page);
#endif
+ if (G.by_depth_in_use > 1)
+ {
+ page_entry *top = G.by_depth[G.by_depth_in_use-1];
+ int i = entry->index_by_depth;
+
+ /* We cannot free a page from a context deeper than the current
+ one. */
+ gcc_assert (entry->context_depth == top->context_depth);
+
+ /* Put top element into freed slot. */
+ G.by_depth[i] = top;
+ G.save_in_use[i] = G.save_in_use[G.by_depth_in_use-1];
+ top->index_by_depth = i;
+ }
+ --G.by_depth_in_use;
+
+ adjust_depth ();
+
entry->next = G.free_pages;
G.free_pages = entry;
}
/* Release the free page cache to the system. */
static void
-release_pages ()
+release_pages (void)
{
#ifdef USING_MMAP
page_entry *p, *next;
/* This table provides a fast way to determine ceil(log_2(size)) for
allocation requests. The minimum allocation size is eight bytes. */
-
-static unsigned char size_lookup[257] =
+#define NUM_SIZE_LOOKUP 512
+static unsigned char size_lookup[NUM_SIZE_LOOKUP] =
{
3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 4, 4, 4, 4, 4, 4,
4, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5, 5,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, 8,
- 8
+ 8, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9,
+ 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, 9
};
-/* Allocate a chunk of memory of SIZE bytes. If ZERO is nonzero, the
- memory is zeroed; otherwise, its contents are undefined. */
+/* Typed allocation function. Does nothing special in this collector. */
+
+void *
+ggc_alloc_typed_stat (enum gt_types_enum type ATTRIBUTE_UNUSED, size_t size
+ MEM_STAT_DECL)
+{
+ return ggc_alloc_stat (size PASS_MEM_STAT);
+}
+
+/* Allocate a chunk of memory of SIZE bytes. Its contents are undefined. */
void *
-ggc_alloc (size)
- size_t size;
+ggc_alloc_stat (size_t size MEM_STAT_DECL)
{
- unsigned order, word, bit, object_offset;
+ size_t order, word, bit, object_offset, object_size;
struct page_entry *entry;
void *result;
- if (size <= 256)
- order = size_lookup[size];
+ if (size < NUM_SIZE_LOOKUP)
+ {
+ order = size_lookup[size];
+ object_size = OBJECT_SIZE (order);
+ }
else
{
- order = 9;
- while (size > OBJECT_SIZE (order))
+ order = 10;
+ while (size > (object_size = OBJECT_SIZE (order)))
order++;
}
struct page_entry *new_entry;
new_entry = alloc_page (order);
- /* If this is the only entry, it's also the tail. */
+ new_entry->index_by_depth = G.by_depth_in_use;
+ push_by_depth (new_entry, 0);
+
+ /* We can skip context depths, if we do, make sure we go all the
+ way to the new depth. */
+ while (new_entry->context_depth >= G.depth_in_use)
+ push_depth (G.by_depth_in_use-1);
+
+ /* If this is the only entry, it's also the tail. If it is not
+ the only entry, then we must update the PREV pointer of the
+ ENTRY (G.pages[order]) to point to our new page entry. */
if (entry == NULL)
G.page_tails[order] = new_entry;
+ else
+ entry->prev = new_entry;
- /* Put new pages at the head of the page list. */
+ /* Put new pages at the head of the page list. By definition the
+ entry at the head of the list always has a NULL pointer. */
new_entry->next = entry;
+ new_entry->prev = NULL;
entry = new_entry;
G.pages[order] = new_entry;
word = bit = 0;
while (~entry->in_use_p[word] == 0)
++word;
+
+#if GCC_VERSION >= 3004
+ bit = __builtin_ctzl (~entry->in_use_p[word]);
+#else
while ((entry->in_use_p[word] >> bit) & 1)
++bit;
+#endif
+
hint = word * HOST_BITS_PER_LONG + bit;
}
/* Next time, try the next bit. */
entry->next_bit_hint = hint + 1;
- object_offset = hint * OBJECT_SIZE (order);
+ object_offset = hint * object_size;
}
/* Set the in-use bit. */
&& entry->next != NULL
&& entry->next->num_free_objects > 0)
{
+ /* We have a new head for the list. */
G.pages[order] = entry->next;
+
+ /* We are moving ENTRY to the end of the page table list.
+ The new page at the head of the list will have NULL in
+ its PREV field and ENTRY will have NULL in its NEXT field. */
+ entry->next->prev = NULL;
entry->next = NULL;
+
+ /* Append ENTRY to the tail of the list. */
+ entry->prev = G.page_tails[order];
G.page_tails[order]->next = entry;
G.page_tails[order] = entry;
}
/* Calculate the object's address. */
result = entry->page + object_offset;
+#ifdef GATHER_STATISTICS
+ ggc_record_overhead (OBJECT_SIZE (order), OBJECT_SIZE (order) - size,
+ result PASS_MEM_STAT);
+#endif
#ifdef ENABLE_GC_CHECKING
/* Keep poisoning-by-writing-0xaf the object, in an attempt to keep the
exact same semantics in presence of memory bugs, regardless of
ENABLE_VALGRIND_CHECKING. We override this request below. Drop the
handle to avoid handle leak. */
- VALGRIND_DISCARD (VALGRIND_MAKE_WRITABLE (result, OBJECT_SIZE (order)));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, object_size));
/* `Poison' the entire allocated object, including any padding at
the end. */
- memset (result, 0xaf, OBJECT_SIZE (order));
+ memset (result, 0xaf, object_size);
/* Make the bytes after the end of the object unaccessible. Discard the
handle to avoid handle leak. */
- VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS ((char *) result + size,
- OBJECT_SIZE (order) - size));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS ((char *) result + size,
+ object_size - size));
#endif
/* Tell Valgrind that the memory is there, but its content isn't
defined. The bytes at the end of the object are still marked
unaccessible. */
- VALGRIND_DISCARD (VALGRIND_MAKE_WRITABLE (result, size));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (result, size));
/* Keep track of how many bytes are being allocated. This
information is used in deciding when to collect. */
- G.allocated += OBJECT_SIZE (order);
+ G.allocated += object_size;
+
+ /* For timevar statistics. */
+ timevar_ggc_mem_total += object_size;
+
+#ifdef GATHER_STATISTICS
+ {
+ size_t overhead = object_size - size;
+
+ G.stats.total_overhead += overhead;
+ G.stats.total_allocated += object_size;
+ G.stats.total_overhead_per_order[order] += overhead;
+ G.stats.total_allocated_per_order[order] += object_size;
+
+ if (size <= 32)
+ {
+ G.stats.total_overhead_under32 += overhead;
+ G.stats.total_allocated_under32 += object_size;
+ }
+ if (size <= 64)
+ {
+ G.stats.total_overhead_under64 += overhead;
+ G.stats.total_allocated_under64 += object_size;
+ }
+ if (size <= 128)
+ {
+ G.stats.total_overhead_under128 += overhead;
+ G.stats.total_allocated_under128 += object_size;
+ }
+ }
+#endif
if (GGC_DEBUG_LEVEL >= 3)
fprintf (G.debug_file,
"Allocating object, requested size=%lu, actual=%lu at %p on %p\n",
- (unsigned long) size, (unsigned long) OBJECT_SIZE (order), result,
- (PTR) entry);
+ (unsigned long) size, (unsigned long) object_size, result,
+ (void *) entry);
return result;
}
static objects, stack variables, or memory allocated with malloc. */
int
-ggc_set_mark (p)
- const void *p;
+ggc_set_mark (const void *p)
{
page_entry *entry;
unsigned bit, word;
/* Look up the page on which the object is alloced. If the object
wasn't allocated by the collector, we'll probably die. */
entry = lookup_page_table_entry (p);
-#ifdef ENABLE_CHECKING
- if (entry == NULL)
- abort ();
-#endif
+ gcc_assert (entry);
/* Calculate the index of the object on the page; this is its bit
position in the in_use_p bitmap. */
static objects, stack variables, or memory allocated with malloc. */
int
-ggc_marked_p (p)
- const void *p;
+ggc_marked_p (const void *p)
{
page_entry *entry;
unsigned bit, word;
/* Look up the page on which the object is alloced. If the object
wasn't allocated by the collector, we'll probably die. */
entry = lookup_page_table_entry (p);
-#ifdef ENABLE_CHECKING
- if (entry == NULL)
- abort ();
-#endif
+ gcc_assert (entry);
/* Calculate the index of the object on the page; this is its bit
position in the in_use_p bitmap. */
/* Return the size of the gc-able object P. */
size_t
-ggc_get_size (p)
- const void *p;
+ggc_get_size (const void *p)
{
page_entry *pe = lookup_page_table_entry (p);
return OBJECT_SIZE (pe->order);
}
+
+/* Release the memory for object P. */
+
+void
+ggc_free (void *p)
+{
+ page_entry *pe = lookup_page_table_entry (p);
+ size_t order = pe->order;
+ size_t size = OBJECT_SIZE (order);
+
+#ifdef GATHER_STATISTICS
+ ggc_free_overhead (p);
+#endif
+
+ if (GGC_DEBUG_LEVEL >= 3)
+ fprintf (G.debug_file,
+ "Freeing object, actual size=%lu, at %p on %p\n",
+ (unsigned long) size, p, (void *) pe);
+
+#ifdef ENABLE_GC_CHECKING
+ /* Poison the data, to indicate the data is garbage. */
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (p, size));
+ memset (p, 0xa5, size);
+#endif
+ /* Let valgrind know the object is free. */
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (p, size));
+
+#ifdef ENABLE_GC_ALWAYS_COLLECT
+ /* In the completely-anal-checking mode, we do *not* immediately free
+ the data, but instead verify that the data is *actually* not
+ reachable the next time we collect. */
+ {
+ struct free_object *fo = XNEW (struct free_object);
+ fo->object = p;
+ fo->next = G.free_object_list;
+ G.free_object_list = fo;
+ }
+#else
+ {
+ unsigned int bit_offset, word, bit;
+
+ G.allocated -= size;
+
+ /* Mark the object not-in-use. */
+ bit_offset = OFFSET_TO_BIT (((const char *) p) - pe->page, order);
+ word = bit_offset / HOST_BITS_PER_LONG;
+ bit = bit_offset % HOST_BITS_PER_LONG;
+ pe->in_use_p[word] &= ~(1UL << bit);
+
+ if (pe->num_free_objects++ == 0)
+ {
+ page_entry *p, *q;
+
+ /* If the page is completely full, then it's supposed to
+ be after all pages that aren't. Since we've freed one
+ object from a page that was full, we need to move the
+ page to the head of the list.
+
+ PE is the node we want to move. Q is the previous node
+ and P is the next node in the list. */
+ q = pe->prev;
+ if (q && q->num_free_objects == 0)
+ {
+ p = pe->next;
+
+ q->next = p;
+
+ /* If PE was at the end of the list, then Q becomes the
+ new end of the list. If PE was not the end of the
+ list, then we need to update the PREV field for P. */
+ if (!p)
+ G.page_tails[order] = q;
+ else
+ p->prev = q;
+
+ /* Move PE to the head of the list. */
+ pe->next = G.pages[order];
+ pe->prev = NULL;
+ G.pages[order]->prev = pe;
+ G.pages[order] = pe;
+ }
+
+ /* Reset the hint bit to point to the only free object. */
+ pe->next_bit_hint = bit_offset;
+ }
+ }
+#endif
+}
\f
/* Subroutine of init_ggc which computes the pair of numbers used to
perform division by OBJECT_SIZE (order) and fills in inverse_table[].
constants). */
static void
-compute_inverse (order)
- unsigned order;
+compute_inverse (unsigned order)
{
- unsigned size, inv, e;
-
- /* There can be only one object per "page" in a bucket for sizes
- larger than half a machine page; it will always have offset zero. */
- if (OBJECT_SIZE (order) > G.pagesize/2)
- {
- if (OBJECTS_PER_PAGE (order) != 1)
- abort ();
-
- DIV_MULT (order) = 1;
- DIV_SHIFT (order) = 0;
- return;
- }
+ size_t size, inv;
+ unsigned int e;
size = OBJECT_SIZE (order);
e = 0;
/* Initialize the ggc-mmap allocator. */
void
-init_ggc ()
+init_ggc (void)
{
unsigned order;
#ifdef HAVE_MMAP_DEV_ZERO
G.dev_zero_fd = open ("/dev/zero", O_RDONLY);
if (G.dev_zero_fd == -1)
- abort ();
+ internal_error ("open /dev/zero: %m");
#endif
#if 0
can't get something useful, give up. */
p = alloc_anon (NULL, G.pagesize);
- if ((size_t)p & (G.pagesize - 1))
- abort ();
+ gcc_assert (!((size_t)p & (G.pagesize - 1)));
}
/* We have a good page, might as well hold onto it... */
- e = (struct page_entry *) xcalloc (1, sizeof (struct page_entry));
+ e = XCNEW (struct page_entry);
e->bytes = G.pagesize;
e->page = p;
e->next = G.free_pages;
int o;
int i;
- o = size_lookup[OBJECT_SIZE (order)];
- for (i = OBJECT_SIZE (order); size_lookup [i] == o; --i)
+ i = OBJECT_SIZE (order);
+ if (i >= NUM_SIZE_LOOKUP)
+ continue;
+
+ for (o = size_lookup[i]; o == size_lookup [i]; --i)
size_lookup[i] = order;
}
+
+ G.depth_in_use = 0;
+ G.depth_max = 10;
+ G.depth = XNEWVEC (unsigned int, G.depth_max);
+
+ G.by_depth_in_use = 0;
+ G.by_depth_max = INITIAL_PTE_COUNT;
+ G.by_depth = XNEWVEC (page_entry *, G.by_depth_max);
+ G.save_in_use = XNEWVEC (unsigned long *, G.by_depth_max);
}
-/* Increment the `GC context'. Objects allocated in an outer context
- are never freed, eliminating the need to register their roots. */
+/* Start a new GGC zone. */
-void
-ggc_push_context ()
+struct alloc_zone *
+new_ggc_zone (const char *name ATTRIBUTE_UNUSED)
{
- ++G.context_depth;
+ return NULL;
+}
- /* Die on wrap. */
- if (G.context_depth >= HOST_BITS_PER_LONG)
- abort ();
+/* Destroy a GGC zone. */
+void
+destroy_ggc_zone (struct alloc_zone *zone ATTRIBUTE_UNUSED)
+{
}
/* Merge the SAVE_IN_USE_P and IN_USE_P arrays in P so that IN_USE_P
reflects reality. Recalculate NUM_FREE_OBJECTS as well. */
static void
-ggc_recalculate_in_use_p (p)
- page_entry *p;
+ggc_recalculate_in_use_p (page_entry *p)
{
unsigned int i;
size_t num_objects;
/* Something is in use if it is marked, or if it was in use in a
context further down the context stack. */
- p->in_use_p[i] |= p->save_in_use_p[i];
+ p->in_use_p[i] |= save_in_use_p (p)[i];
/* Decrement the free object count for every object allocated. */
for (j = p->in_use_p[i]; j; j >>= 1)
p->num_free_objects -= (j & 1);
}
- if (p->num_free_objects >= num_objects)
- abort ();
-}
-
-/* Decrement the `GC context'. All objects allocated since the
- previous ggc_push_context are migrated to the outer context. */
-
-void
-ggc_pop_context ()
-{
- unsigned long omask;
- unsigned order, depth;
-
- depth = --G.context_depth;
- omask = (unsigned long)1 << (depth + 1);
-
- if (!((G.context_depth_allocations | G.context_depth_collections) & omask))
- return;
-
- G.context_depth_allocations |= (G.context_depth_allocations & omask) >> 1;
- G.context_depth_allocations &= omask - 1;
- G.context_depth_collections &= omask - 1;
-
- /* Any remaining pages in the popped context are lowered to the new
- current context; i.e. objects allocated in the popped context and
- left over are imported into the previous context. */
- for (order = 2; order < NUM_ORDERS; order++)
- {
- page_entry *p;
-
- for (p = G.pages[order]; p != NULL; p = p->next)
- {
- if (p->context_depth > depth)
- p->context_depth = depth;
-
- /* If this page is now in the topmost context, and we'd
- saved its allocation state, restore it. */
- else if (p->context_depth == depth && p->save_in_use_p)
- {
- ggc_recalculate_in_use_p (p);
- free (p->save_in_use_p);
- p->save_in_use_p = 0;
- }
- }
- }
+ gcc_assert (p->num_free_objects < num_objects);
}
\f
/* Unmark all objects. */
-static inline void
-clear_marks ()
+static void
+clear_marks (void)
{
unsigned order;
size_t num_objects = OBJECTS_IN_PAGE (p);
size_t bitmap_size = BITMAP_SIZE (num_objects + 1);
-#ifdef ENABLE_CHECKING
/* The data should be page-aligned. */
- if ((size_t) p->page & (G.pagesize - 1))
- abort ();
-#endif
+ gcc_assert (!((size_t) p->page & (G.pagesize - 1)));
/* Pages that aren't in the topmost context are not collected;
nevertheless, we need their in-use bit vectors to store GC
marks. So, back them up first. */
if (p->context_depth < G.context_depth)
{
- if (! p->save_in_use_p)
- p->save_in_use_p = xmalloc (bitmap_size);
- memcpy (p->save_in_use_p, p->in_use_p, bitmap_size);
+ if (! save_in_use_p (p))
+ save_in_use_p (p) = xmalloc (bitmap_size);
+ memcpy (save_in_use_p (p), p->in_use_p, bitmap_size);
}
/* Reset reset the number of free objects and clear the
/* Free all empty pages. Partially empty pages need no attention
because the `mark' bit doubles as an `unused' bit. */
-static inline void
-sweep_pages ()
+static void
+sweep_pages (void)
{
unsigned order;
/* Loop until all entries have been examined. */
done = (p == last);
-
+
num_objects = OBJECTS_IN_PAGE (p);
/* Add all live objects on this page to the count of
/* Remove the page if it's empty. */
else if (live_objects == 0)
{
+ /* If P was the first page in the list, then NEXT
+ becomes the new first page in the list, otherwise
+ splice P out of the forward pointers. */
if (! previous)
G.pages[order] = next;
else
previous->next = next;
+
+ /* Splice P out of the back pointers too. */
+ if (next)
+ next->prev = previous;
/* Are we removing the last element? */
if (p == G.page_tails[order])
{
/* Move p to the end of the list. */
p->next = NULL;
+ p->prev = G.page_tails[order];
G.page_tails[order]->next = p;
/* Update the tail pointer... */
G.pages[order] = next;
else
previous->next = next;
+
+ /* And update the backpointer in NEXT if necessary. */
+ if (next)
+ next->prev = previous;
+
p = previous;
}
}
else if (p != G.pages[order])
{
previous->next = p->next;
+
+ /* Update the backchain in the next node if it exists. */
+ if (p->next)
+ p->next->prev = previous;
+
+ /* Move P to the head of the list. */
p->next = G.pages[order];
+ p->prev = NULL;
+ G.pages[order]->prev = p;
+
+ /* Update the head pointer. */
G.pages[order] = p;
+
/* Are we moving the last element? */
if (G.page_tails[order] == p)
G.page_tails[order] = previous;
#ifdef ENABLE_GC_CHECKING
/* Clobber all free objects. */
-static inline void
-poison_pages ()
+static void
+poison_pages (void)
{
unsigned order;
so the exact same memory semantics is kept, in case
there are memory errors. We override this request
below. */
- VALGRIND_DISCARD (VALGRIND_MAKE_WRITABLE (object, size));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_UNDEFINED (object,
+ size));
memset (object, 0xa5, size);
/* Drop the handle to avoid handle leak. */
- VALGRIND_DISCARD (VALGRIND_MAKE_NOACCESS (object, size));
+ VALGRIND_DISCARD (VALGRIND_MAKE_MEM_NOACCESS (object, size));
}
}
}
}
}
+#else
+#define poison_pages()
+#endif
+
+#ifdef ENABLE_GC_ALWAYS_COLLECT
+/* Validate that the reportedly free objects actually are. */
+
+static void
+validate_free_objects (void)
+{
+ struct free_object *f, *next, *still_free = NULL;
+
+ for (f = G.free_object_list; f ; f = next)
+ {
+ page_entry *pe = lookup_page_table_entry (f->object);
+ size_t bit, word;
+
+ bit = OFFSET_TO_BIT ((char *)f->object - pe->page, pe->order);
+ word = bit / HOST_BITS_PER_LONG;
+ bit = bit % HOST_BITS_PER_LONG;
+ next = f->next;
+
+ /* Make certain it isn't visible from any root. Notice that we
+ do this check before sweep_pages merges save_in_use_p. */
+ gcc_assert (!(pe->in_use_p[word] & (1UL << bit)));
+
+ /* If the object comes from an outer context, then retain the
+ free_object entry, so that we can verify that the address
+ isn't live on the stack in some outer context. */
+ if (pe->context_depth != G.context_depth)
+ {
+ f->next = still_free;
+ still_free = f;
+ }
+ else
+ free (f);
+ }
+
+ G.free_object_list = still_free;
+}
+#else
+#define validate_free_objects()
#endif
/* Top level mark-and-sweep routine. */
void
-ggc_collect ()
+ggc_collect (void)
{
/* Avoid frequent unnecessary work by skipping collection if the
total allocations haven't expanded much since the last
float min_expand = allocated_last_gc * PARAM_VALUE (GGC_MIN_EXPAND) / 100;
- if (G.allocated < allocated_last_gc + min_expand)
+ if (G.allocated < allocated_last_gc + min_expand && !ggc_force_collect)
return;
timevar_push (TV_GC);
if (!quiet_flag)
fprintf (stderr, " {GC %luk -> ", (unsigned long) G.allocated / 1024);
+ if (GGC_DEBUG_LEVEL >= 2)
+ fprintf (G.debug_file, "BEGIN COLLECTING\n");
/* Zero the total allocated bytes. This will be recalculated in the
sweep phase. */
clear_marks ();
ggc_mark_roots ();
-
-#ifdef ENABLE_GC_CHECKING
- poison_pages ();
+#ifdef GATHER_STATISTICS
+ ggc_prune_overhead_list ();
#endif
-
+ poison_pages ();
+ validate_free_objects ();
sweep_pages ();
G.allocated_last_gc = G.allocated;
if (!quiet_flag)
fprintf (stderr, "%luk}", (unsigned long) G.allocated / 1024);
+ if (GGC_DEBUG_LEVEL >= 2)
+ fprintf (G.debug_file, "END COLLECTING\n");
}
/* Print allocation statistics. */
: ((x) < 1024*1024*10 \
? (x) / 1024 \
: (x) / (1024*1024))))
-#define LABEL(x) ((x) < 1024*10 ? ' ' : ((x) < 1024*1024*10 ? 'k' : 'M'))
+#define STAT_LABEL(x) ((x) < 1024*10 ? ' ' : ((x) < 1024*1024*10 ? 'k' : 'M'))
void
-ggc_print_statistics ()
+ggc_print_statistics (void)
{
struct ggc_statistics stats;
unsigned int i;
/* Collect some information about the various sizes of
allocation. */
- fprintf (stderr, "\n%-5s %10s %10s %10s\n",
+ fprintf (stderr,
+ "Memory still allocated at the end of the compilation process\n");
+ fprintf (stderr, "%-5s %10s %10s %10s\n",
"Size", "Allocated", "Used", "Overhead");
for (i = 0; i < NUM_ORDERS; ++i)
{
for (p = G.pages[i]; p; p = p->next)
{
allocated += p->bytes;
- in_use +=
+ in_use +=
(OBJECTS_IN_PAGE (p) - p->num_free_objects) * OBJECT_SIZE (i);
overhead += (sizeof (page_entry) - sizeof (long)
}
fprintf (stderr, "%-5lu %10lu%c %10lu%c %10lu%c\n",
(unsigned long) OBJECT_SIZE (i),
- SCALE (allocated), LABEL (allocated),
- SCALE (in_use), LABEL (in_use),
- SCALE (overhead), LABEL (overhead));
+ SCALE (allocated), STAT_LABEL (allocated),
+ SCALE (in_use), STAT_LABEL (in_use),
+ SCALE (overhead), STAT_LABEL (overhead));
total_overhead += overhead;
}
fprintf (stderr, "%-5s %10lu%c %10lu%c %10lu%c\n", "Total",
- SCALE (G.bytes_mapped), LABEL (G.bytes_mapped),
- SCALE (G.allocated), LABEL(G.allocated),
- SCALE (total_overhead), LABEL (total_overhead));
+ SCALE (G.bytes_mapped), STAT_LABEL (G.bytes_mapped),
+ SCALE (G.allocated), STAT_LABEL(G.allocated),
+ SCALE (total_overhead), STAT_LABEL (total_overhead));
+
+#ifdef GATHER_STATISTICS
+ {
+ fprintf (stderr, "\nTotal allocations and overheads during the compilation process\n");
+
+ fprintf (stderr, "Total Overhead: %10lld\n",
+ G.stats.total_overhead);
+ fprintf (stderr, "Total Allocated: %10lld\n",
+ G.stats.total_allocated);
+
+ fprintf (stderr, "Total Overhead under 32B: %10lld\n",
+ G.stats.total_overhead_under32);
+ fprintf (stderr, "Total Allocated under 32B: %10lld\n",
+ G.stats.total_allocated_under32);
+ fprintf (stderr, "Total Overhead under 64B: %10lld\n",
+ G.stats.total_overhead_under64);
+ fprintf (stderr, "Total Allocated under 64B: %10lld\n",
+ G.stats.total_allocated_under64);
+ fprintf (stderr, "Total Overhead under 128B: %10lld\n",
+ G.stats.total_overhead_under128);
+ fprintf (stderr, "Total Allocated under 128B: %10lld\n",
+ G.stats.total_allocated_under128);
+
+ for (i = 0; i < NUM_ORDERS; i++)
+ if (G.stats.total_allocated_per_order[i])
+ {
+ fprintf (stderr, "Total Overhead page size %7lu: %10lld\n",
+ (unsigned long) OBJECT_SIZE (i),
+ G.stats.total_overhead_per_order[i]);
+ fprintf (stderr, "Total Allocated page size %7lu: %10lld\n",
+ (unsigned long) OBJECT_SIZE (i),
+ G.stats.total_allocated_per_order[i]);
+ }
+ }
+#endif
}
\f
struct ggc_pch_data
{
- struct ggc_pch_ondisk
+ struct ggc_pch_ondisk
{
unsigned totals[NUM_ORDERS];
} d;
};
struct ggc_pch_data *
-init_ggc_pch ()
+init_ggc_pch (void)
{
- return xcalloc (sizeof (struct ggc_pch_data), 1);
+ return XCNEW (struct ggc_pch_data);
}
-void
-ggc_pch_count_object (d, x, size)
- struct ggc_pch_data *d;
- void *x ATTRIBUTE_UNUSED;
- size_t size;
+void
+ggc_pch_count_object (struct ggc_pch_data *d, void *x ATTRIBUTE_UNUSED,
+ size_t size, bool is_string ATTRIBUTE_UNUSED,
+ enum gt_types_enum type ATTRIBUTE_UNUSED)
{
unsigned order;
- if (size <= 256)
+ if (size < NUM_SIZE_LOOKUP)
order = size_lookup[size];
else
{
- order = 9;
+ order = 10;
while (size > OBJECT_SIZE (order))
order++;
}
-
+
d->d.totals[order]++;
}
-
+
size_t
-ggc_pch_total_size (d)
- struct ggc_pch_data *d;
+ggc_pch_total_size (struct ggc_pch_data *d)
{
size_t a = 0;
unsigned i;
}
void
-ggc_pch_this_base (d, base)
- struct ggc_pch_data *d;
- void *base;
+ggc_pch_this_base (struct ggc_pch_data *d, void *base)
{
size_t a = (size_t) base;
unsigned i;
-
+
for (i = 0; i < NUM_ORDERS; i++)
{
d->base[i] = a;
char *
-ggc_pch_alloc_object (d, x, size)
- struct ggc_pch_data *d;
- void *x ATTRIBUTE_UNUSED;
- size_t size;
+ggc_pch_alloc_object (struct ggc_pch_data *d, void *x ATTRIBUTE_UNUSED,
+ size_t size, bool is_string ATTRIBUTE_UNUSED,
+ enum gt_types_enum type ATTRIBUTE_UNUSED)
{
unsigned order;
char *result;
-
- if (size <= 256)
+
+ if (size < NUM_SIZE_LOOKUP)
order = size_lookup[size];
else
{
- order = 9;
+ order = 10;
while (size > OBJECT_SIZE (order))
order++;
}
return result;
}
-void
-ggc_pch_prepare_write (d, f)
- struct ggc_pch_data * d ATTRIBUTE_UNUSED;
- FILE * f ATTRIBUTE_UNUSED;
+void
+ggc_pch_prepare_write (struct ggc_pch_data *d ATTRIBUTE_UNUSED,
+ FILE *f ATTRIBUTE_UNUSED)
{
/* Nothing to do. */
}
void
-ggc_pch_write_object (d, f, x, newx, size)
- struct ggc_pch_data * d ATTRIBUTE_UNUSED;
- FILE *f;
- void *x;
- void *newx ATTRIBUTE_UNUSED;
- size_t size;
+ggc_pch_write_object (struct ggc_pch_data *d ATTRIBUTE_UNUSED,
+ FILE *f, void *x, void *newx ATTRIBUTE_UNUSED,
+ size_t size, bool is_string ATTRIBUTE_UNUSED)
{
unsigned order;
+ static const char emptyBytes[256];
- if (size <= 256)
+ if (size < NUM_SIZE_LOOKUP)
order = size_lookup[size];
else
{
- order = 9;
+ order = 10;
while (size > OBJECT_SIZE (order))
order++;
}
-
+
if (fwrite (x, size, 1, f) != 1)
- fatal_io_error ("can't write PCH file");
+ fatal_error ("can't write PCH file: %m");
- /* In the current implementation, SIZE is always equal to
- OBJECT_SIZE (order) and so the fseek is never executed. */
- if (size != OBJECT_SIZE (order)
- && fseek (f, OBJECT_SIZE (order) - size, SEEK_CUR) != 0)
- fatal_io_error ("can't write PCH file");
+ /* If SIZE is not the same as OBJECT_SIZE(order), then we need to pad the
+ object out to OBJECT_SIZE(order). This happens for strings. */
+
+ if (size != OBJECT_SIZE (order))
+ {
+ unsigned padding = OBJECT_SIZE(order) - size;
+
+ /* To speed small writes, we use a nulled-out array that's larger
+ than most padding requests as the source for our null bytes. This
+ permits us to do the padding with fwrite() rather than fseek(), and
+ limits the chance the OS may try to flush any outstanding writes. */
+ if (padding <= sizeof(emptyBytes))
+ {
+ if (fwrite (emptyBytes, 1, padding, f) != padding)
+ fatal_error ("can't write PCH file");
+ }
+ else
+ {
+ /* Larger than our buffer? Just default to fseek. */
+ if (fseek (f, padding, SEEK_CUR) != 0)
+ fatal_error ("can't write PCH file");
+ }
+ }
d->written[order]++;
if (d->written[order] == d->d.totals[order]
&& fseek (f, ROUND_UP_VALUE (d->d.totals[order] * OBJECT_SIZE (order),
G.pagesize),
SEEK_CUR) != 0)
- fatal_io_error ("can't write PCH file");
+ fatal_error ("can't write PCH file: %m");
}
void
-ggc_pch_finish (d, f)
- struct ggc_pch_data * d;
- FILE *f;
+ggc_pch_finish (struct ggc_pch_data *d, FILE *f)
{
if (fwrite (&d->d, sizeof (d->d), 1, f) != 1)
- fatal_io_error ("can't write PCH file");
+ fatal_error ("can't write PCH file: %m");
free (d);
}
+/* Move the PCH PTE entries just added to the end of by_depth, to the
+ front. */
+
+static void
+move_ptes_to_front (int count_old_page_tables, int count_new_page_tables)
+{
+ unsigned i;
+
+ /* First, we swap the new entries to the front of the varrays. */
+ page_entry **new_by_depth;
+ unsigned long **new_save_in_use;
+
+ new_by_depth = XNEWVEC (page_entry *, G.by_depth_max);
+ new_save_in_use = XNEWVEC (unsigned long *, G.by_depth_max);
+
+ memcpy (&new_by_depth[0],
+ &G.by_depth[count_old_page_tables],
+ count_new_page_tables * sizeof (void *));
+ memcpy (&new_by_depth[count_new_page_tables],
+ &G.by_depth[0],
+ count_old_page_tables * sizeof (void *));
+ memcpy (&new_save_in_use[0],
+ &G.save_in_use[count_old_page_tables],
+ count_new_page_tables * sizeof (void *));
+ memcpy (&new_save_in_use[count_new_page_tables],
+ &G.save_in_use[0],
+ count_old_page_tables * sizeof (void *));
+
+ free (G.by_depth);
+ free (G.save_in_use);
+
+ G.by_depth = new_by_depth;
+ G.save_in_use = new_save_in_use;
+
+ /* Now update all the index_by_depth fields. */
+ for (i = G.by_depth_in_use; i > 0; --i)
+ {
+ page_entry *p = G.by_depth[i-1];
+ p->index_by_depth = i-1;
+ }
+
+ /* And last, we update the depth pointers in G.depth. The first
+ entry is already 0, and context 0 entries always start at index
+ 0, so there is nothing to update in the first slot. We need a
+ second slot, only if we have old ptes, and if we do, they start
+ at index count_new_page_tables. */
+ if (count_old_page_tables)
+ push_depth (count_new_page_tables);
+}
+
void
-ggc_pch_read (f, addr)
- FILE *f;
- void *addr;
+ggc_pch_read (FILE *f, void *addr)
{
struct ggc_pch_ondisk d;
unsigned i;
char *offs = addr;
-
- /* We've just read in a PCH file. So, every object that used to be allocated
- is now free. */
+ unsigned long count_old_page_tables;
+ unsigned long count_new_page_tables;
+
+ count_old_page_tables = G.by_depth_in_use;
+
+ /* We've just read in a PCH file. So, every object that used to be
+ allocated is now free. */
clear_marks ();
-#ifdef GGC_POISON
+#ifdef ENABLE_GC_CHECKING
poison_pages ();
#endif
+ /* Since we free all the allocated objects, the free list becomes
+ useless. Validate it now, which will also clear it. */
+ validate_free_objects();
/* No object read from a PCH file should ever be freed. So, set the
context depth to 1, and set the depth of all the currently-allocated
pages to be 1 too. PCH pages will have depth 0. */
- if (G.context_depth != 0)
- abort ();
+ gcc_assert (!G.context_depth);
G.context_depth = 1;
for (i = 0; i < NUM_ORDERS; i++)
{
/* Allocate the appropriate page-table entries for the pages read from
the PCH file. */
if (fread (&d, sizeof (d), 1, f) != 1)
- fatal_io_error ("can't read PCH file");
-
+ fatal_error ("can't read PCH file: %m");
+
for (i = 0; i < NUM_ORDERS; i++)
{
struct page_entry *entry;
size_t bytes;
size_t num_objs;
size_t j;
-
+
if (d.totals[i] == 0)
continue;
-
+
bytes = ROUND_UP (d.totals[i] * OBJECT_SIZE (i), G.pagesize);
num_objs = bytes / OBJECT_SIZE (i);
- entry = xcalloc (1, (sizeof (struct page_entry)
+ entry = xcalloc (1, (sizeof (struct page_entry)
- sizeof (long)
+ BITMAP_SIZE (num_objs + 1)));
entry->bytes = bytes;
entry->num_free_objects = 0;
entry->order = i;
- for (j = 0;
+ for (j = 0;
j + HOST_BITS_PER_LONG <= num_objs + 1;
j += HOST_BITS_PER_LONG)
entry->in_use_p[j / HOST_BITS_PER_LONG] = -1;
for (; j < num_objs + 1; j++)
- entry->in_use_p[j / HOST_BITS_PER_LONG]
+ entry->in_use_p[j / HOST_BITS_PER_LONG]
|= 1L << (j % HOST_BITS_PER_LONG);
- for (pte = entry->page;
- pte < entry->page + entry->bytes;
+ for (pte = entry->page;
+ pte < entry->page + entry->bytes;
pte += G.pagesize)
set_page_table_entry (pte, entry);
else
G.pages[i] = entry;
G.page_tails[i] = entry;
+
+ /* We start off by just adding all the new information to the
+ end of the varrays, later, we will move the new information
+ to the front of the varrays, as the PCH page tables are at
+ context 0. */
+ push_by_depth (entry, 0);
}
+ /* Now, we update the various data structures that speed page table
+ handling. */
+ count_new_page_tables = G.by_depth_in_use - count_old_page_tables;
+
+ move_ptes_to_front (count_old_page_tables, count_new_page_tables);
+
/* Update the statistics. */
G.allocated = G.allocated_last_gc = offs - (char *)addr;
}
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