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pch: Add support for relocation of the PCH data [PR71934]

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The following patch adds support for relocation of the PCH blob on PCH
restore if we don't manage to get the preferred map slot for it.
The GTY stuff knows where all the pointers are, after all it relocates
it once during PCH save from the addresses where it was initially allocated
to addresses in the preferred map slot.
But, if we were to do it solely using GTY info upon PCH restore, we'd need
another set of GTY functions, which I think would make it less maintainable
and I think it would also be more costly at PCH restore time.  Those
functions would need to call something to add bias to pointers that haven't
been marked yet and make sure not to add bias to any pointer twice.

So, this patch instead builds a relocation table (sorted list of addresses
in the blob which needs relocation) at PCH save time, stores it in a very
compact form into the gch file and upon restore, adjusts pointers in GTY
roots (that is right away in the root structures) and the addresses in the
relocation table.
The cost on stdc++.gch/O2g.gch (previously 85MB large) is about 3% file size
growth, there are 2.5 million pointers that need relocation in the gch blob
and the relocation table uses uleb128 for address deltas and needs ~1.01 bytes
for one address that needs relocation, and about 20% compile time during
PCH save (I think it is mainly because of the need to qsort those 2.5
million pointers).  On PCH restore, if it doesn't need relocation (the usual
case), it is just an extra fread of sizeof (size_t) data and fseek
(in my tests real time on vanilla tree for #include <bits/stdc++.h> CU
was ~0.175s and with the patch but no relocation ~0.173s), while if it needs
relocation it took ~0.193s, i.e. 11.5% slower.
Without PCH that
 #include <bits/stdc++.h>
 int i;
testcase compiles with -O2 -g in ~1.199s, i.e. 6.2 times slower than PCH with
relocation and 6.9 times than PCH without relocation.

The discovery of the pointers in the blob that need relocation is done
in the relocate_ptrs hook which does the pointer relocation during PCH save.
Unfortunately, I had to make one change to the gengtype stuff due to the
nested_ptr feature of GTY, which some libcpp headers and stringpool.c use.
The relocate_ptrs hook had 2 arguments, pointer to the pointer and a cookie.
When relocate_ptrs is done, in most cases it is called solely on the
subfields of the current object, so e.g.
          if ((void *)(x) == this_obj)
            op (&((*x).u.fld[0].rt_rtx), cookie);
so relocate_ptrs can assert that ptr_p is within the
state->ptrs[state->ptrs_i]->obj ..
state->ptrs[state->ptrs_i]->obj+state->ptrs[state->ptrs_i]->size-sizeof(void*)
range and compute from that the address in the blob which will need
relocation (state->ptrs[state->ptrs_i]->new_addr is the new address
given to it and ptr_p-state->ptrs[state->ptrs_i]->obj is the relative
offset.  Unfortunately, for nested_ptr gengtype emits something like:
      {
        union tree_node * x0 =
          ((*x).val.node.node) ? HT_IDENT_TO_GCC_IDENT (HT_NODE (((*x).val.node.node))) : NULL;
        if ((void *)(x) == this_obj)
          op (&(x0), cookie);
        (*x).val.node.node = (x0) ? CPP_HASHNODE (GCC_IDENT_TO_HT_IDENT ((x0))) : NULL;
      }
so relocate_ptrs is called with an address of some temporary variable and
so doesn't know where the pointer will finally be.
So, I've added another argument to relocate_ptrs (and to
gt_pointer_operator).  For the most common case I pass NULL as the new middle
argument to that function, first one remains pointer to the pointer that
needs adjustment and last the cookie.  The NULL seems to be cheap to compute
and short in the gt*.[ch] files and stands for ptr_p is an address within
the this_obj's range, remember its address.  For the nested_ptr case, the
new middle argument contains actual address of the pointer that might need
to be relocated, so instead of the above
          op (&(x0), &((*x).val.node.node), cookie);
in there.  And finally, e.g. for the reorder case I need a way to tell
restore_ptrs to ignore a particular address for the relocation purposes
and only treat it the old way.  I've used for that the case when
the first and second arguments are equal.

In order to enable support for mapping PCH as fallback at different
addresses than the preferred ones, a small change is needed to the
host pch_use_address hooks.  One change I've done to all of them is
the change of the type of the first argument from void * to void *&,
such that the actual address can be told to the callers (or shall I
instead use void **?), but another change that still needs to be done
in them if they want the relocation is actually not fail if they couldn't
get a preferred address, but instead modify what the first argument
refers to.  I've done that only for host-linux.c and Iain is testing
similar change for host-darwin.c.  Didn't change hpux, netbsd, openbsd,
solaris, mingw32 or the fallbacks because I can't test those.

Tested also with the:
--- gcc/config/host-linux.c.jj  2021-12-06 22:22:42.007777367 +0100
+++ gcc/config/host-linux.c     2021-12-07 00:21:53.052674040 +0100
@@ -191,6 +191,8 @@ linux_gt_pch_use_address (void *&base, s
   if (size == 0)
     return -1;

+base = (char *) base + ((size + 8191) & (size_t) -4096);
+
   /* Try to map the file with MAP_PRIVATE.  */
   addr = mmap (base, size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, offset);

hack which forces all PCH restores to be relocated.  An earlier version of the
patch has been also regrest with base = (char *) base + 16384; in that spot,
so both relocation to a non-overlapping spot and to an overlapping spot have
been tested.

2021-12-09  Jakub Jelinek  <jakub@redhat.com>

	PR pch/71934
	* coretypes.h (gt_pointer_operator): Use 3 pointer arguments instead
	of two.
	* gengtype.c (struct walk_type_data): Add in_nested_ptr argument.
	(walk_type): Temporarily set d->in_nested_ptr around nested_ptr
	handling.
	(write_types_local_user_process_field): Pass a new middle pointer
	to gt_pointer_operator op calls, if d->in_nested_ptr pass there
	address of d->prev_val[2], otherwise NULL.
	(write_types_local_process_field): Likewise.
	* ggc-common.c (relocate_ptrs): Add real_ptr_p argument.  If equal
	to ptr_p, do nothing, otherwise if NULL remember ptr_p's
	or if non-NULL real_ptr_p's corresponding new address in
	reloc_addrs_vec.
	(reloc_addrs_vec): New variable.
	(compare_ptr, read_uleb128, write_uleb128): New functions.
	(gt_pch_save): When iterating over objects through relocate_ptrs,
	save current i into state.ptrs_i.  Sort reloc_addrs_vec and emit
	it as uleb128 of differences between pointer addresses into the
	PCH file.
	(gt_pch_restore): Allow restoring of PCH to a different address
	than the preferred one, in that case adjust global pointers by bias
	and also adjust by bias addresses read from the relocation table
	as uleb128 differences.  Otherwise fseek over it.  Perform
	gt_pch_restore_stringpool only after adjusting callbacks and for
	callback adjustments also take into account the bias.
	(default_gt_pch_use_address): Change type of first argument from
	void * to void *&.
	(mmap_gt_pch_use_address): Likewise.
	* ggc-tests.c (gt_pch_nx): Pass NULL as new middle argument to op.
	* hash-map.h (hash_map::pch_nx_helper): Likewise.
	(gt_pch_nx): Likewise.
	* hash-set.h (gt_pch_nx): Likewise.
	* hash-table.h (gt_pch_nx): Likewise.
	* hash-traits.h (ggc_remove::pch_nx): Likewise.
	* hosthooks-def.h (default_gt_pch_use_address): Change type of first
	argument from void * to void *&.
	(mmap_gt_pch_use_address): Likewise.
	* hosthooks.h (struct host_hooks): Change type of first argument of
	gt_pch_use_address hook from void * to void *&.
	* machmode.h (gt_pch_nx): Expect a callback with 3 pointers instead of
	two in the middle argument.
	* poly-int.h (gt_pch_nx): Likewise.
	* stringpool.c (gt_pch_nx): Pass NULL as new middle argument to op.
	* tree-cfg.c (gt_pch_nx): Likewise, except for LOCATION_BLOCK pass
	the same &(block) twice.
	* value-range.h (gt_pch_nx): Pass NULL as new middle argument to op.
	* vec.h (gt_pch_nx): Likewise.
	* wide-int.h (gt_pch_nx): Likewise.
	* config/host-darwin.c (darwin_gt_pch_use_address): Change type of
	first argument from void * to void *&.
	* config/host-darwin.h (darwin_gt_pch_use_address): Likewise.
	* config/host-hpux.c (hpux_gt_pch_use_address): Likewise.
	* config/host-linux.c (linux_gt_pch_use_address): Likewise.  If
	it couldn't succeed to mmap at the preferred location, set base
	to the actual one.  Update addr in the manual reading loop instead of
	base.
	* config/host-netbsd.c (netbsd_gt_pch_use_address): Change type of
	first argument from void * to void *&.
	* config/host-openbsd.c (openbsd_gt_pch_use_address): Likewise.
	* config/host-solaris.c (sol_gt_pch_use_address): Likewise.
	* config/i386/host-mingw32.c (mingw32_gt_pch_use_address): Likewise.
	* config/rs6000/rs6000-gen-builtins.c (write_init_file): Pass NULL
	as new middle argument to op in the generated code.
	* doc/gty.texi: Adjust samples for the addition of middle pointer
	to gt_pointer_operator callback.
gcc/ada/
	* gcc-interface/decl.c (gt_pch_nx): Pass NULL as new middle argument
	to op.
gcc/c-family/
	* c-pch.c (c_common_no_more_pch): Pass a temporary void * var
	with NULL value instead of NULL to host_hooks.gt_pch_use_address.
gcc/c/
	* c-decl.c (resort_field_decl_cmp): Pass the same pointer twice
	to resort_data.new_value.
gcc/cp/
	* module.cc (nop): Add another void * argument.
	* name-lookup.c (resort_member_name_cmp): Pass the same pointer twice
	to resort_data.new_value.
This commit is contained in:
Jakub Jelinek 2021-12-09 15:40:15 +01:00
parent 5791bf7a0a
commit 747380f47d
32 changed files with 268 additions and 72 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
gcc/ada/gcc-interface/decl.c
View File

@ -171,7 +171,7 @@ gt_pch_nx (Entity_Id &)
void
gt_pch_nx (Entity_Id *x, gt_pointer_operator op, void *cookie)
{
op (x, cookie);
op (x, NULL, cookie);
}
struct dummy_type_hasher : ggc_cache_ptr_hash<tree_entity_vec_map>

3
gcc/c-family/c-pch.c
View File

@ -375,7 +375,8 @@ c_common_no_more_pch (void)
if (cpp_get_callbacks (parse_in)->valid_pch)
{
cpp_get_callbacks (parse_in)->valid_pch = NULL;
host_hooks.gt_pch_use_address (NULL, 0, -1, 0);
void *addr = NULL;
host_hooks.gt_pch_use_address (addr, 0, -1, 0);
}
}

4
gcc/c/c-decl.c
View File

@ -9040,8 +9040,8 @@ resort_field_decl_cmp (const void *x_p, const void *y_p)
{
tree d1 = DECL_NAME (*x);
tree d2 = DECL_NAME (*y);
resort_data.new_value (&d1, resort_data.cookie);
resort_data.new_value (&d2, resort_data.cookie);
resort_data.new_value (&d1, &d1, resort_data.cookie);
resort_data.new_value (&d2, &d2, resort_data.cookie);
if (d1 < d2)
return -1;
}

2
gcc/config/host-darwin.c
View File

@ -136,7 +136,7 @@ darwin_gt_pch_get_address (size_t sz, int fd)
fail with -1. */
int
darwin_gt_pch_use_address (void *addr, size_t sz, int fd, size_t off)
darwin_gt_pch_use_address (void *&addr, size_t sz, int fd, size_t off)
{
void *mapped_addr;

2
gcc/config/host-darwin.h
View File

@ -18,7 +18,7 @@
<http://www.gnu.org/licenses/>. */
extern void * darwin_gt_pch_get_address (size_t sz, int fd);
extern int darwin_gt_pch_use_address (void *addr, size_t sz, int fd,
extern int darwin_gt_pch_use_address (void *&addr, size_t sz, int fd,
size_t off);
#undef HOST_HOOKS_GT_PCH_GET_ADDRESS

4
gcc/config/host-hpux.c
View File

@ -24,7 +24,7 @@
#include "hosthooks-def.h"
static void *hpux_gt_pch_get_address (size_t, int);
static int hpux_gt_pch_use_address (void *, size_t, int, size_t);
static int hpux_gt_pch_use_address (void *&, size_t, int, size_t);
#undef HOST_HOOKS_GT_PCH_GET_ADDRESS
#define HOST_HOOKS_GT_PCH_GET_ADDRESS hpux_gt_pch_get_address
@ -78,7 +78,7 @@ hpux_gt_pch_get_address (size_t size, int fd)
little else we can do given the current PCH implementation. */
static int
hpux_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
hpux_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;

16
gcc/config/host-linux.c
View File

@ -181,7 +181,7 @@ linux_gt_pch_get_address (size_t size, int fd)
little else we can do given the current PCH implementation. */
static int
linux_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
linux_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;
@ -204,24 +204,22 @@ linux_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
addr = mmap (base, size, PROT_READ | PROT_WRITE,
MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
if (addr != base)
{
if (addr != (void *) MAP_FAILED)
munmap (addr, size);
return -1;
}
if (addr == (void *) MAP_FAILED)
return -1;
if (lseek (fd, offset, SEEK_SET) == (off_t)-1)
return -1;
base = addr;
while (size)
{
ssize_t nbytes;
nbytes = read (fd, base, MIN (size, (size_t)-1 >> 1));
nbytes = read (fd, addr, MIN (size, (size_t)-1 >> 1));
if (nbytes <= 0)
return -1;
base = (char *) base + nbytes;
addr = (char *) addr + nbytes;
size -= nbytes;
}

2
gcc/config/host-netbsd.c
View File

@ -66,7 +66,7 @@ netbsd_gt_pch_get_address (size_t size, int fd)
mapping the data at BASE, -1 if we couldn't. */
static int
netbsd_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
netbsd_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;

2
gcc/config/host-openbsd.c
View File

@ -66,7 +66,7 @@ openbsd_gt_pch_get_address (size_t size, int fd)
mapping the data at BASE, -1 if we couldn't. */
static int
openbsd_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
openbsd_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;

2
gcc/config/host-solaris.c
View File

@ -105,7 +105,7 @@ sol_gt_pch_get_address (size_t size, int fd)
mapping the data at BASE, -1 if we couldn't. */
static int
sol_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
sol_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;

4
gcc/config/i386/host-mingw32.c
View File

@ -32,7 +32,7 @@
#include <stdlib.h>
static void * mingw32_gt_pch_get_address (size_t, int);
static int mingw32_gt_pch_use_address (void *, size_t, int, size_t);
static int mingw32_gt_pch_use_address (void *&, size_t, int, size_t);
static size_t mingw32_gt_pch_alloc_granularity (void);
#undef HOST_HOOKS_GT_PCH_GET_ADDRESS
@ -118,7 +118,7 @@ mingw32_gt_pch_get_address (size_t size, int)
if the memory is allocated but the data not loaded, return 1 if done. */
static int
mingw32_gt_pch_use_address (void *addr, size_t size, int fd,
mingw32_gt_pch_use_address (void *&addr, size_t size, int fd,
size_t offset)
{
void * mmap_addr;

4
gcc/config/rs6000/rs6000-gen-builtins.c
View File

@ -2886,7 +2886,7 @@ write_init_file (void)
"void gt_pch_nx (bifdata *bd, gt_pointer_operator op, "
"void *cookie)\n");
fprintf (init_file,
"{\n op(&(bd->fntype), cookie);\n}\n\n");
"{\n op(&(bd->fntype), NULL, cookie);\n}\n\n");
fprintf (init_file,
"void gt_ggc_mx (ovlddata *od)\n");
fprintf (init_file,
@ -2899,7 +2899,7 @@ write_init_file (void)
"void gt_pch_nx (ovlddata *od, gt_pointer_operator op, "
"void *cookie)\n");
fprintf (init_file,
"{\n op(&(od->fntype), cookie);\n}\n");
"{\n op(&(od->fntype), NULL, cookie);\n}\n");
return 1;
}

6
gcc/coretypes.h
View File

@ -442,8 +442,10 @@ enum optimize_size_level
};
/* Support for user-provided GGC and PCH markers. The first parameter
is a pointer to a pointer, the second a cookie. */
typedef void (*gt_pointer_operator) (void *, void *);
is a pointer to a pointer, the second either NULL if the pointer to
pointer points into a GC object or the actual pointer address if
the first argument points to a temporary and the third a cookie. */
typedef void (*gt_pointer_operator) (void *, void *, void *);
#if !defined (HAVE_UCHAR)
typedef unsigned char uchar;

2
gcc/cp/module.cc
View File

@ -11750,7 +11750,7 @@ trees_out::mark_class_def (tree defn)
/* Nop sorting, needed for resorting the member vec. */
static void
nop (void *, void *)
nop (void *, void *, void *)
{
}

4
gcc/cp/name-lookup.c
View File

@ -2123,8 +2123,8 @@ resort_member_name_cmp (const void *a_p, const void *b_p)
tree name_a = OVL_NAME (a);
tree name_b = OVL_NAME (b);
resort_data.new_value (&name_a, resort_data.cookie);
resort_data.new_value (&name_b, resort_data.cookie);
resort_data.new_value (&name_a, &name_a, resort_data.cookie);
resort_data.new_value (&name_b, &name_b, resort_data.cookie);
gcc_checking_assert (name_a != name_b);

4
gcc/doc/gty.texi
View File

@ -483,7 +483,7 @@ void gt_pch_nx (my_struct *p)
void gt_pch_nx (my_struct *p, gt_pointer_operator op, void *cookie)
@{
/* For every field 'fld', call the given pointer operator. */
op (&(tp->fld), cookie);
op (&(tp->fld), NULL, cookie);
@}
@end smallexample
@ -536,7 +536,7 @@ void gt_pch_nx (TP<T *> *tp, gt_pointer_operator op, void *cookie)
@{
/* For every field 'fld' of 'tp' with type 'T *', call the given
pointer operator. */
op (&(tp->fld), cookie);
op (&(tp->fld), NULL, cookie);
@}
template<typename T>

23
gcc/gengtype.c
View File

@ -2491,6 +2491,7 @@ struct walk_type_data
int loopcounter;
bool in_ptr_field;
bool have_this_obj;
bool in_nested_ptr;
};
@ -2807,6 +2808,7 @@ walk_type (type_p t, struct walk_type_data *d)
if (nested_ptr_d)
{
const char *oldprevval2 = d->prev_val[2];
bool old_in_nested_ptr = d->in_nested_ptr;
if (!union_or_struct_p (nested_ptr_d->type))
{
@ -2817,6 +2819,7 @@ walk_type (type_p t, struct walk_type_data *d)
}
d->prev_val[2] = d->val;
d->in_nested_ptr = true;
oprintf (d->of, "%*s{\n", d->indent, "");
d->indent += 2;
d->val = xasprintf ("x%d", d->counter++);
@ -2846,6 +2849,7 @@ walk_type (type_p t, struct walk_type_data *d)
oprintf (d->of, "%*s}\n", d->indent, "");
d->val = d->prev_val[2];
d->prev_val[2] = oldprevval2;
d->in_nested_ptr = old_in_nested_ptr;
}
else
d->process_field (t->u.p, d);
@ -3828,12 +3832,17 @@ write_types_local_user_process_field (type_p f, const struct walk_type_data *d)
case TYPE_UNION:
case TYPE_LANG_STRUCT:
case TYPE_STRING:
oprintf (d->of, "%*s op (&(%s), cookie);\n", d->indent, "", d->val);
if (d->in_nested_ptr)
oprintf (d->of, "%*s op (&(%s), &(%s), cookie);\n",
d->indent, "", d->val, d->prev_val[2]);
oprintf (d->of, "%*s op (&(%s), NULL, cookie);\n",
d->indent, "", d->val);
break;
case TYPE_USER_STRUCT:
if (d->in_ptr_field)
oprintf (d->of, "%*s op (&(%s), cookie);\n", d->indent, "", d->val);
oprintf (d->of, "%*s op (&(%s), NULL, cookie);\n",
d->indent, "", d->val);
else
oprintf (d->of, "%*s gt_pch_nx (&(%s), op, cookie);\n",
d->indent, "", d->val);
@ -3911,14 +3920,20 @@ write_types_local_process_field (type_p f, const struct walk_type_data *d)
case TYPE_STRING:
oprintf (d->of, "%*sif ((void *)(%s) == this_obj)\n", d->indent, "",
d->prev_val[3]);
oprintf (d->of, "%*s op (&(%s), cookie);\n", d->indent, "", d->val);
if (d->in_nested_ptr)
oprintf (d->of, "%*s op (&(%s), &(%s), cookie);\n",
d->indent, "", d->val, d->prev_val[2]);
else
oprintf (d->of, "%*s op (&(%s), NULL, cookie);\n",
d->indent, "", d->val);
break;
case TYPE_USER_STRUCT:
oprintf (d->of, "%*sif ((void *)(%s) == this_obj)\n", d->indent, "",
d->prev_val[3]);
if (d->in_ptr_field)
oprintf (d->of, "%*s op (&(%s), cookie);\n", d->indent, "", d->val);
oprintf (d->of, "%*s op (&(%s), NULL, cookie);\n",
d->indent, "", d->val);
else
oprintf (d->of, "%*s gt_pch_nx (&(%s), op, cookie);\n",
d->indent, "", d->val);

202
gcc/ggc-common.c
View File

@ -40,7 +40,7 @@ static ggc_statistics *ggc_stats;
struct traversal_state;
static int compare_ptr_data (const void *, const void *);
static void relocate_ptrs (void *, void *);
static void relocate_ptrs (void *, void *, void *);
static void write_pch_globals (const struct ggc_root_tab * const *tab,
struct traversal_state *state);
@ -247,6 +247,7 @@ saving_hasher::equal (const ptr_data *p1, const void *p2)
static hash_table<saving_hasher> *saving_htab;
static vec<void *> callback_vec;
static vec<void *> reloc_addrs_vec;
/* Register an object in the hash table. */
@ -363,10 +364,10 @@ compare_ptr_data (const void *p1_p, const void *p2_p)
/* Callbacks for note_ptr_fn. */
static void
relocate_ptrs (void *ptr_p, void *state_p)
relocate_ptrs (void *ptr_p, void *real_ptr_p, void *state_p)
{
void **ptr = (void **)ptr_p;
struct traversal_state *state ATTRIBUTE_UNUSED
struct traversal_state *state
= (struct traversal_state *)state_p;
struct ptr_data *result;
@ -377,6 +378,19 @@ relocate_ptrs (void *ptr_p, void *state_p)
saving_htab->find_with_hash (*ptr, POINTER_HASH (*ptr));
gcc_assert (result);
*ptr = result->new_addr;
if (ptr_p == real_ptr_p)
return;
if (real_ptr_p == NULL)
real_ptr_p = ptr_p;
gcc_assert (real_ptr_p >= state->ptrs[state->ptrs_i]->obj
&& ((char *) real_ptr_p + sizeof (void *)
<= ((char *) state->ptrs[state->ptrs_i]->obj
+ state->ptrs[state->ptrs_i]->size)));
void *addr
= (void *) ((char *) state->ptrs[state->ptrs_i]->new_addr
+ ((char *) real_ptr_p
- (char *) state->ptrs[state->ptrs_i]->obj));
reloc_addrs_vec.safe_push (addr);
}
/* Write out, after relocation, the pointers in TAB. */
@ -411,6 +425,61 @@ write_pch_globals (const struct ggc_root_tab * const *tab,
}
}
/* Callback for qsort. */
static int
compare_ptr (const void *p1_p, const void *p2_p)
{
void *p1 = *(void *const *)p1_p;
void *p2 = *(void *const *)p2_p;
return (((uintptr_t)p1 > (uintptr_t)p2)
- ((uintptr_t)p1 < (uintptr_t)p2));
}
/* Decode one uleb128 from P, return first byte after it, store
decoded value into *VAL. */
static unsigned char *
read_uleb128 (unsigned char *p, size_t *val)
{
unsigned int shift = 0;
unsigned char byte;
size_t result;
result = 0;
do
{
byte = *p++;
result |= ((size_t) byte & 0x7f) << shift;
shift += 7;
}
while (byte & 0x80);
*val = result;
return p;
}
/* Store VAL as uleb128 at P, return length in bytes. */
static size_t
write_uleb128 (unsigned char *p, size_t val)
{
size_t len = 0;
do
{
unsigned char byte = (val & 0x7f);
val >>= 7;
if (val != 0)
/* More bytes to follow. */
byte |= 0x80;
*p++ = byte;
++len;
}
while (val != 0);
return len;
}
/* Hold the information we need to mmap the file back in. */
struct mmap_info
@ -511,6 +580,7 @@ gt_pch_save (FILE *f)
/* Actually write out the objects. */
for (i = 0; i < state.count; i++)
{
state.ptrs_i = i;
if (this_object_size < state.ptrs[i]->size)
{
this_object_size = state.ptrs[i]->size;
@ -591,7 +661,42 @@ gt_pch_save (FILE *f)
vbits.release ();
#endif
reloc_addrs_vec.qsort (compare_ptr);
size_t reloc_addrs_size = 0;
void *last_addr = NULL;
unsigned char uleb128_buf[sizeof (size_t) * 2];
for (void *addr : reloc_addrs_vec)
{
gcc_assert ((uintptr_t) addr >= (uintptr_t) mmi.preferred_base
&& ((uintptr_t) addr + sizeof (void *)
< (uintptr_t) mmi.preferred_base + mmi.size));
if (addr == last_addr)
continue;
if (last_addr == NULL)
last_addr = mmi.preferred_base;
size_t diff = (uintptr_t) addr - (uintptr_t) last_addr;
reloc_addrs_size += write_uleb128 (uleb128_buf, diff);
last_addr = addr;
}
if (fwrite (&reloc_addrs_size, sizeof (reloc_addrs_size), 1, f) != 1)
fatal_error (input_location, "cannot write PCH file: %m");
last_addr = NULL;
for (void *addr : reloc_addrs_vec)
{
if (addr == last_addr)
continue;
if (last_addr == NULL)
last_addr = mmi.preferred_base;
size_t diff = (uintptr_t) addr - (uintptr_t) last_addr;
reloc_addrs_size = write_uleb128 (uleb128_buf, diff);
if (fwrite (uleb128_buf, 1, reloc_addrs_size, f) != reloc_addrs_size)
fatal_error (input_location, "cannot write PCH file: %m");
last_addr = addr;
}
ggc_pch_finish (state.d, state.f);
gt_pch_fixup_stringpool ();
unsigned num_callbacks = callback_vec.length ();
@ -608,6 +713,7 @@ gt_pch_save (FILE *f)
delete saving_htab;
saving_htab = NULL;
callback_vec.release ();
reloc_addrs_vec.release ();
}
/* Read the state of the compiler back in from F. */
@ -660,6 +766,7 @@ gt_pch_restore (FILE *f)
if (fread (&mmi, sizeof (mmi), 1, f) != 1)
fatal_error (input_location, "cannot read PCH file: %m");
void *orig_preferred_base = mmi.preferred_base;
result = host_hooks.gt_pch_use_address (mmi.preferred_base, mmi.size,
fileno (f), mmi.offset);
@ -667,7 +774,7 @@ gt_pch_restore (FILE *f)
address needed. */
if (result < 0)
{
sorry_at (input_location, "PCH relocation is not yet supported");
sorry_at (input_location, "PCH allocation failure");
/* There is no point in continuing from here, we will only end up
with a crashed (most likely hanging) compiler. */
exit (-1);
@ -685,9 +792,75 @@ gt_pch_restore (FILE *f)
else if (fseek (f, mmi.offset + mmi.size, SEEK_SET) != 0)
fatal_error (input_location, "cannot read PCH file: %m");
ggc_pch_read (f, mmi.preferred_base);
size_t reloc_addrs_size;
if (fread (&reloc_addrs_size, sizeof (reloc_addrs_size), 1, f) != 1)
fatal_error (input_location, "cannot read PCH file: %m");
gt_pch_restore_stringpool ();
if (orig_preferred_base != mmi.preferred_base)
{
uintptr_t bias
= (uintptr_t) mmi.preferred_base - (uintptr_t) orig_preferred_base;
/* Adjust all the global pointers by bias. */
line_table = new_line_table;
for (rt = gt_ggc_rtab; *rt; rt++)
for (rti = *rt; rti->base != NULL; rti++)
for (i = 0; i < rti->nelt; i++)
{
char *addr = (char *)rti->base + rti->stride * i;
char *p;
memcpy (&p, addr, sizeof (void *));
if ((uintptr_t) p >= (uintptr_t) orig_preferred_base
&& (uintptr_t) p < (uintptr_t) orig_preferred_base + mmi.size)
{
p = (char *) ((uintptr_t) p + bias);
memcpy (addr, &p, sizeof (void *));
}
}
new_line_table = line_table;
line_table = save_line_table;
/* And adjust all the pointers in the image by bias too. */
char *addr = (char *) mmi.preferred_base;
unsigned char uleb128_buf[4096], *uleb128_ptr = uleb128_buf;
while (reloc_addrs_size != 0)
{
size_t this_size
= MIN (reloc_addrs_size,
(size_t) (4096 - (uleb128_ptr - uleb128_buf)));
if (fread (uleb128_ptr, 1, this_size, f) != this_size)
fatal_error (input_location, "cannot read PCH file: %m");
unsigned char *uleb128_end = uleb128_ptr + this_size;
if (this_size != reloc_addrs_size)
uleb128_end -= 2 * sizeof (size_t);
uleb128_ptr = uleb128_buf;
while (uleb128_ptr < uleb128_end)
{
size_t diff;
uleb128_ptr = read_uleb128 (uleb128_ptr, &diff);
addr = (char *) ((uintptr_t) addr + diff);
char *p;
memcpy (&p, addr, sizeof (void *));
gcc_assert ((uintptr_t) p >= (uintptr_t) orig_preferred_base
&& ((uintptr_t) p
< (uintptr_t) orig_preferred_base + mmi.size));
p = (char *) ((uintptr_t) p + bias);
memcpy (addr, &p, sizeof (void *));
}
reloc_addrs_size -= this_size;
if (reloc_addrs_size == 0)
break;
this_size = uleb128_end + 2 * sizeof (size_t) - uleb128_ptr;
memcpy (uleb128_buf, uleb128_ptr, this_size);
uleb128_ptr = uleb128_buf + this_size;
}
}
else if (fseek (f, (mmi.offset + mmi.size + sizeof (reloc_addrs_size)
+ reloc_addrs_size), SEEK_SET) != 0)
fatal_error (input_location, "cannot read PCH file: %m");
ggc_pch_read (f, mmi.preferred_base);
void (*pch_save) (FILE *);
unsigned num_callbacks;
@ -696,23 +869,28 @@ gt_pch_restore (FILE *f)
fatal_error (input_location, "cannot read PCH file: %m");
if (pch_save != &gt_pch_save)
{
uintptr_t bias = (uintptr_t) &gt_pch_save - (uintptr_t) pch_save;
uintptr_t binbias = (uintptr_t) &gt_pch_save - (uintptr_t) pch_save;
void **ptrs = XNEWVEC (void *, num_callbacks);
unsigned i;
uintptr_t bias
= (uintptr_t) mmi.preferred_base - (uintptr_t) orig_preferred_base;
if (fread (ptrs, sizeof (void *), num_callbacks, f) != num_callbacks)
fatal_error (input_location, "cannot read PCH file: %m");
for (i = 0; i < num_callbacks; ++i)
{
memcpy (&pch_save, ptrs[i], sizeof (pch_save));
pch_save = (void (*) (FILE *)) ((uintptr_t) pch_save + bias);
memcpy (ptrs[i], &pch_save, sizeof (pch_save));
void *ptr = (void *) ((uintptr_t) ptrs[i] + bias);
memcpy (&pch_save, ptr, sizeof (pch_save));
pch_save = (void (*) (FILE *)) ((uintptr_t) pch_save + binbias);
memcpy (ptr, &pch_save, sizeof (pch_save));
}
XDELETE (ptrs);
}
else if (fseek (f, num_callbacks * sizeof (void *), SEEK_CUR) != 0)
fatal_error (input_location, "cannot read PCH file: %m");
gt_pch_restore_stringpool ();
/* Barring corruption of the PCH file, the restored line table should be
complete and usable. */
line_table = new_line_table;
@ -736,7 +914,7 @@ default_gt_pch_get_address (size_t size ATTRIBUTE_UNUSED,
of the PCH file would be required. */
int
default_gt_pch_use_address (void *base, size_t size, int fd ATTRIBUTE_UNUSED,
default_gt_pch_use_address (void *&base, size_t size, int fd ATTRIBUTE_UNUSED,
size_t offset ATTRIBUTE_UNUSED)
{
void *addr = xmalloc (size);
@ -782,7 +960,7 @@ mmap_gt_pch_get_address (size_t size, int fd)
mapped with something. */
int
mmap_gt_pch_use_address (void *base, size_t size, int fd, size_t offset)
mmap_gt_pch_use_address (void *&base, size_t size, int fd, size_t offset)
{
void *addr;

2
gcc/ggc-tests.c
View File

@ -415,7 +415,7 @@ gt_pch_nx (user_struct *p)
static void
gt_pch_nx (user_struct *p, gt_pointer_operator op, void *cookie)
{
op (&(p->m_ptr), cookie);
op (&(p->m_ptr), NULL, cookie);
}
/* Verify that GTY((user)) works. */

4
gcc/hash-map.h
View File

@ -111,7 +111,7 @@ class GTY((user)) hash_map
static void
pch_nx_helper (T *&x, gt_pointer_operator op, void *cookie)
{
op (&x, cookie);
op (&x, NULL, cookie);
}
/* The overloads below should match those in ggc.h. */
@ -336,7 +336,7 @@ template<typename K, typename V, typename H>
static inline void
gt_pch_nx (hash_map<K, V, H> *h, gt_pointer_operator op, void *cookie)
{
op (&h->m_table.m_entries, cookie);
op (&h->m_table.m_entries, NULL, cookie);
}
enum hm_alloc { hm_heap = false, hm_ggc = true };

2
gcc/hash-set.h
View File

@ -206,7 +206,7 @@ template<typename K, typename H>
static inline void
gt_pch_nx (hash_set<K, false, H> *h, gt_pointer_operator op, void *cookie)
{
op (&h->m_table.m_entries, cookie);
op (&h->m_table.m_entries, NULL, cookie);
}
#endif

2
gcc/hash-table.h
View File

@ -1206,7 +1206,7 @@ template<typename D>
static inline void
gt_pch_nx (hash_table<D> *h, gt_pointer_operator op, void *cookie)
{
op (&h->m_entries, cookie);
op (&h->m_entries, NULL, cookie);
}
template<typename H>

2
gcc/hash-traits.h
View File

@ -254,7 +254,7 @@ struct ggc_remove
static void
pch_nx (T &p, gt_pointer_operator op, void *cookie)
{
op (&p, cookie);
op (&p, NULL, cookie);
}
};

4
gcc/hosthooks-def.h
View File

@ -35,10 +35,10 @@ along with GCC; see the file COPYING3. If not see
default_gt_pch_alloc_granularity
extern void* default_gt_pch_get_address (size_t, int);
extern int default_gt_pch_use_address (void *, size_t, int, size_t);
extern int default_gt_pch_use_address (void *&, size_t, int, size_t);
extern size_t default_gt_pch_alloc_granularity (void);
extern void* mmap_gt_pch_get_address (size_t, int);
extern int mmap_gt_pch_use_address (void *, size_t, int, size_t);
extern int mmap_gt_pch_use_address (void *&, size_t, int, size_t);
/* The structure is defined in hosthooks.h. */
#define HOST_HOOKS_INITIALIZER { \

10
gcc/hosthooks.h
View File

@ -30,10 +30,12 @@ struct host_hooks
void * (*gt_pch_get_address) (size_t size, int fd);
/* ADDR is an address returned by gt_pch_get_address. Attempt to allocate
SIZE bytes at the same address and load it with the data from FD at
OFFSET. Return -1 if we couldn't allocate memory at ADDR, return 0
if the memory is allocated but the data not loaded, return 1 if done. */
int (*gt_pch_use_address) (void *addr, size_t size, int fd, size_t offset);
SIZE bytes at the same address (preferrably) or some other address
and load it with the data from FD at OFFSET. Return -1 if we couldn't
allocate memory, otherwise update ADDR to the actual address where it got
allocated, return 0 if the memory is allocated but the data not loaded,
return 1 if done. */
int (*gt_pch_use_address) (void *&addr, size_t size, int fd, size_t offset);
/* Return the alignment required for allocating virtual memory. Usually
this is the same as pagesize. */

2
gcc/machmode.h
View File

@ -1199,7 +1199,7 @@ gt_pch_nx (pod_mode<T> *)
template<typename T>
void
gt_pch_nx (pod_mode<T> *, void (*) (void *, void *), void *)
gt_pch_nx (pod_mode<T> *, void (*) (void *, void *, void *), void *)
{
}

2
gcc/poly-int.h
View File

@ -2717,7 +2717,7 @@ gt_pch_nx (poly_int_pod<N, C> *)
template<unsigned int N, typename C>
void
gt_pch_nx (poly_int_pod<N, C> *, void (*) (void *, void *), void *)
gt_pch_nx (poly_int_pod<N, C> *, void (*) (void *, void *, void *), void *)
{
}

2
gcc/stringpool.c
View File

@ -225,7 +225,7 @@ gt_pch_nx (unsigned char& x ATTRIBUTE_UNUSED)
void
gt_pch_nx (unsigned char *x, gt_pointer_operator op, void *cookie)
{
op (x, cookie);
op (x, NULL, cookie);
}
/* Handle saving and restoring the string pool for PCH. */

10
gcc/tree-cfg.c
View File

@ -9946,13 +9946,13 @@ void
gt_pch_nx (edge_def *e, gt_pointer_operator op, void *cookie)
{
tree block = LOCATION_BLOCK (e->goto_locus);
op (&(e->src), cookie);
op (&(e->dest), cookie);
op (&(e->src), NULL, cookie);
op (&(e->dest), NULL, cookie);
if (current_ir_type () == IR_GIMPLE)
op (&(e->insns.g), cookie);
op (&(e->insns.g), NULL, cookie);
else
op (&(e->insns.r), cookie);
op (&(block), cookie);
op (&(e->insns.r), NULL, cookie);
op (&(block), &(block), cookie);
}
#if CHECKING_P

4
gcc/value-range.h
View File

@ -365,8 +365,8 @@ gt_pch_nx (irange *x, gt_pointer_operator op, void *cookie)
{
for (unsigned i = 0; i < x->m_num_ranges; ++i)
{
op (&x->m_base[i * 2], cookie);
op (&x->m_base[i * 2 + 1], cookie);
op (&x->m_base[i * 2], NULL, cookie);
op (&x->m_base[i * 2 + 1], NULL, cookie);
}
}

2
gcc/vec.h
View File

@ -1388,7 +1388,7 @@ void
gt_pch_nx (vec<T *, A, vl_embed> *v, gt_pointer_operator op, void *cookie)
{
for (unsigned i = 0; i < v->length (); i++)
op (&((*v)[i]), cookie);
op (&((*v)[i]), NULL, cookie);
}
template<typename T, typename A>

4
gcc/wide-int.h
View File

@ -3338,7 +3338,7 @@ gt_pch_nx (generic_wide_int <T> *)
template<typename T>
void
gt_pch_nx (generic_wide_int <T> *, void (*) (void *, void *), void *)
gt_pch_nx (generic_wide_int <T> *, void (*) (void *, void *, void *), void *)
{
}
@ -3356,7 +3356,7 @@ gt_pch_nx (trailing_wide_ints <N> *)
template<int N>
void
gt_pch_nx (trailing_wide_ints <N> *, void (*) (void *, void *), void *)
gt_pch_nx (trailing_wide_ints <N> *, void (*) (void *, void *, void *), void *)
{
}