procyberian/gcc
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

re PR tree-optimization/18291 (ICE in merge_alias_info)

Browse source 
PR tree-optimization/18291
	* tree-ssa-copy.c (merge_alias_info): Fix merging of
	flow-sensitive alias information.  If the new pointer has no
	name tag, copy it from the original pointer.  Otherwise, make
	sure that the pointed-to sets have a common intersection.

testsuite/ChangeLog

	PR tree-optimization/18291
	* testsuite/gcc.c-torture/compile/pr18291.c: New test.

From-SVN: r91574
This commit is contained in:
Diego Novillo 2004-12-01 18:54:04 +00:00 • committed by Diego Novillo
parent 28a6dfca3d
commit 986583fd5d
4 changed files with 59 additions and 12 deletions
Show stats Download patch file Download diff file Expand all files Collapse all files

8
gcc/ChangeLog
View file

@ -1,3 +1,11 @@
2004-12-01 Diego Novillo <dnovillo@redhat.com>
PR tree-optimization/18291
* tree-ssa-copy.c (merge_alias_info): Fix merging of
flow-sensitive alias information. If the new pointer has no
name tag, copy it from the original pointer. Otherwise, make
sure that the pointed-to sets have a common intersection.
2004-12-01 Richard Henderson <rth@redhat.com>
PR rtl-opt/15289

5
gcc/testsuite/ChangeLog
View file

@ -1,3 +1,8 @@
2004-12-01 Diego Novillo <dnovillo@redhat.com>
PR tree-optimization/18291
* testsuite/gcc.c-torture/compile/pr18291.c: New test.
2004-12-01 Nathan Sidwell <nathan@codesourcery.com>
PR C++/18729

12
gcc/testsuite/gcc.c-torture/compile/pr18291.c Normal file
View file

@ -0,0 +1,12 @@
int baz(int k2)
{
int i, j, *p, k = 1, k1 = 0;
if (k2)
p = &j;
else
p = &i;
if (k1)
*p = 0 , p = &k;
*p = 1;
return k;
}

46
gcc/tree-ssa-copy.c
View file

@ -178,7 +178,6 @@ merge_alias_info (tree orig, tree new)
tree orig_sym = SSA_NAME_VAR (orig);
var_ann_t new_ann = var_ann (new_sym);
var_ann_t orig_ann = var_ann (orig_sym);
struct ptr_info_def *new_ptr_info;
struct ptr_info_def *orig_ptr_info;
gcc_assert (POINTER_TYPE_P (TREE_TYPE (orig)));
@ -203,18 +202,41 @@ merge_alias_info (tree orig, tree new)
else
gcc_assert (new_ann->type_mem_tag == orig_ann->type_mem_tag);
/* Synchronize flow sensitive alias information. If both pointers
had flow information and they are inconsistent, then something
has gone wrong. */
new_ptr_info = get_ptr_info (new);
orig_ptr_info = get_ptr_info (orig);
orig_ptr_info = SSA_NAME_PTR_INFO (orig);
if (orig_ptr_info && orig_ptr_info->name_mem_tag)
{
struct ptr_info_def *new_ptr_info = get_ptr_info (new);
if (new_ptr_info->name_mem_tag == NULL_TREE)
memcpy (new_ptr_info, orig_ptr_info, sizeof (*new_ptr_info));
else if (orig_ptr_info->name_mem_tag == NULL_TREE)
memcpy (orig_ptr_info, new_ptr_info, sizeof (*orig_ptr_info));
else if (orig_ptr_info->name_mem_tag != new_ptr_info->name_mem_tag)
abort ();
if (new_ptr_info->name_mem_tag == NULL_TREE)
{
/* If ORIG had a name tag, it means that was dereferenced in
the code, and since pointer NEW will now replace every
occurrence of ORIG, we have to make sure that NEW has an
appropriate tag. If, NEW did not have a name tag, get it
from ORIG. */
memcpy (new_ptr_info, orig_ptr_info, sizeof (*new_ptr_info));
new_ptr_info->pt_vars = BITMAP_GGC_ALLOC ();
bitmap_copy (new_ptr_info->pt_vars, orig_ptr_info->pt_vars);
new_ptr_info->name_mem_tag = orig_ptr_info->name_mem_tag;
}
else
{
/* If NEW already had a name tag, nothing needs to be done.
Note that pointer NEW may actually have a different set of
pointed-to variables.
However, since NEW is being copy-propagated into ORIG, it must
always be true that the pointed-to set for pointer NEW is the
same, or a subset, of the pointed-to set for pointer ORIG. If
this isn't the case, we shouldn't have been able to do the
propagation of NEW into ORIG. */
#if defined ENABLE_CHECKING
if (orig_ptr_info->pt_vars && new_ptr_info->pt_vars)
gcc_assert (bitmap_intersect_p (new_ptr_info->pt_vars,
orig_ptr_info->pt_vars));
#endif
}
}
}