Skip to content

R
riscv-gcc-1
Commit 630d3fad by Richard Guenther Committed by Richard Biener
Options

re PR rtl-optimization/44164 (Aliasing bug triggered by Boost.Bind/Boost.Function) 

2010-05-26  Richard Guenther  <rguenther@suse.de>

	PR rtl-optimization/44164
	* tree-ssa-alias.c (aliasing_component_refs_p): Fix the
	no-common access-path disambiguation.
	(indirect_ref_may_alias_decl_p): Adjust.
	(indirect_refs_may_alias_p): Likewise.
	(refs_may_alias_p_1): Likewise.

	* gcc.c-torture/execute/pr44164.c: New testcase.
	* g++.dg/tree-ssa/pr13146.C: Adjust.

From-SVN: r159861
parent b9b6c084
Showing with 84 additions and 10 deletions
gcc/ChangeLog
2010-05-26 Richard Guenther <rguenther@suse.de>
PR rtl-optimization/44164
* tree-ssa-alias.c (aliasing_component_refs_p): Fix the
no-common access-path disambiguation.
(indirect_ref_may_alias_decl_p): Adjust.
(indirect_refs_may_alias_p): Likewise.
(refs_may_alias_p_1): Likewise.
2010-05-26 Steven Bosscher <steven@gcc.gnu.org>
* c-typeck.c: Do not include expr.h.
......
gcc/testsuite/ChangeLog
2010-05-26 Richard Guenther <rguenther@suse.de>
PR rtl-optimization/44164
* gcc.c-torture/execute/pr44164.c: New testcase.
* g++.dg/tree-ssa/pr13146.C: Adjust.
2010-05-26 Paul Thomas <pault@gcc.gnu.org>
PR fortran/40011
......
gcc/testsuite/g++.dg/tree-ssa/pr13146.C
......@@ -30,7 +30,10 @@ class multi: public third, public second
{
public:
short s;
char f3;
/* The following field used to be of type char but that causes
class multi to effectively get alias-set zero which we end
up not optimizing because of the fix for PR44164. */
int f3;
};
extern void link_error ();
......
gcc/testsuite/gcc.c-torture/execute/pr44164.c 0 → 100644
struct X {
struct Y {
struct YY {
struct Z {
int i;
} c;
} bb;
} b;
} a;
int __attribute__((noinline, noclone))
foo (struct Z *p)
{
int i = p->i;
a.b = (struct Y){};
return p->i + i;
}
extern void abort (void);
int main()
{
a.b.bb.c.i = 1;
if (foo (&a.b.bb.c) != 1)
abort ();
return 0;
}
gcc/tree-ssa-alias.c
......@@ -563,13 +563,21 @@ same_type_for_tbaa (tree type1, tree type2)
/* Determine if the two component references REF1 and REF2 which are
based on access types TYPE1 and TYPE2 and of which at least one is based
on an indirect reference may alias. */
on an indirect reference may alias. REF2 is the only one that can
be a decl in which case REF2_IS_DECL is true.
REF1_ALIAS_SET, BASE1_ALIAS_SET, REF2_ALIAS_SET and BASE2_ALIAS_SET
are the respective alias sets. */
static bool
aliasing_component_refs_p (tree ref1, tree type1,
alias_set_type ref1_alias_set,
alias_set_type base1_alias_set,
HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,
tree ref2, tree type2,
HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2)
alias_set_type ref2_alias_set,
alias_set_type base2_alias_set,
HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,
bool ref2_is_decl)
{
/* If one reference is a component references through pointers try to find a
common base and apply offset based disambiguation. This handles
......@@ -613,8 +621,20 @@ aliasing_component_refs_p (tree ref1, tree type1,
offset1 -= offadj;
return ranges_overlap_p (offset1, max_size1, offset2, max_size2);
}
/* If we have two type access paths B1.path1 and B2.path2 they may
only alias if either B1 is in B2.path2 or B2 is in B1.path1. */
only alias if either B1 is in B2.path2 or B2 is in B1.path1.
But we can still have a path that goes B1.path1...B2.path2 with
a part that we do not see. So we can only disambiguate now
if there is no B2 in the tail of path1 and no B1 on the
tail of path2. */
if (base1_alias_set == ref2_alias_set
|| alias_set_subset_of (base1_alias_set, ref2_alias_set))
return true;
/* If this is ptr vs. decl then we know there is no ptr ... decl path. */
if (!ref2_is_decl)
return (base2_alias_set == ref1_alias_set
|| alias_set_subset_of (base2_alias_set, ref1_alias_set));
return false;
}
......@@ -649,9 +669,11 @@ decl_refs_may_alias_p (tree base1,
static bool
indirect_ref_may_alias_decl_p (tree ref1, tree ptr1,
HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,
alias_set_type ref1_alias_set,
alias_set_type base1_alias_set,
tree ref2, tree base2,
HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,
alias_set_type ref2_alias_set,
alias_set_type base2_alias_set)
{
/* If only one reference is based on a variable, they cannot alias if
......@@ -695,9 +717,11 @@ indirect_ref_may_alias_decl_p (tree ref1, tree ptr1,
&& handled_component_p (ref1)
&& handled_component_p (ref2))
return aliasing_component_refs_p (ref1, TREE_TYPE (TREE_TYPE (ptr1)),
ref1_alias_set, base1_alias_set,
offset1, max_size1,
ref2, TREE_TYPE (base2),
offset2, max_size2);
ref2_alias_set, base2_alias_set,
offset2, max_size2, true);
return true;
}
......@@ -712,9 +736,11 @@ indirect_ref_may_alias_decl_p (tree ref1, tree ptr1,
static bool
indirect_refs_may_alias_p (tree ref1, tree ptr1,
HOST_WIDE_INT offset1, HOST_WIDE_INT max_size1,
alias_set_type ref1_alias_set,
alias_set_type base1_alias_set,
tree ref2, tree ptr2,
HOST_WIDE_INT offset2, HOST_WIDE_INT max_size2,
alias_set_type ref2_alias_set,
alias_set_type base2_alias_set)
{
/* If both bases are based on pointers they cannot alias if they may not
......@@ -756,9 +782,11 @@ indirect_refs_may_alias_p (tree ref1, tree ptr1,
&& handled_component_p (ref1)
&& handled_component_p (ref2))
return aliasing_component_refs_p (ref1, TREE_TYPE (TREE_TYPE (ptr1)),
ref1_alias_set, base1_alias_set,
offset1, max_size1,
ref2, TREE_TYPE (TREE_TYPE (ptr2)),
offset2, max_size2);
ref2_alias_set, base2_alias_set,
offset2, max_size2, false);
return true;
}
......@@ -911,14 +939,18 @@ refs_may_alias_p_1 (ao_ref *ref1, ao_ref *ref2, bool tbaa_p)
set = tbaa_p ? -1 : 0;
if (var1_p && ind2_p)
return indirect_ref_may_alias_decl_p (ref2->ref, TREE_OPERAND (base2, 0),
offset2, max_size2, set,
offset2, max_size2,
ao_ref_alias_set (ref2), set,
ref1->ref, base1,
offset1, max_size1, set);
offset1, max_size1,
ao_ref_alias_set (ref1), set);
else if (ind1_p && ind2_p)
return indirect_refs_may_alias_p (ref1->ref, TREE_OPERAND (base1, 0),
offset1, max_size1, set,
offset1, max_size1,
ao_ref_alias_set (ref1), set,
ref2->ref, TREE_OPERAND (base2, 0),
offset2, max_size2, set);
offset2, max_size2,
ao_ref_alias_set (ref2), set);
gcc_unreachable ();
}
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment