The following fixes a bug in PTA that caused const/pure calls and
calls with fn spec attribute to have mishandled return solutions
or CALLCLOBBERED solutions.
Bootstrapped and tested on x86_64-unknown-linux-gnu, no testcase
for the reported issue (I failed to massage the three-file fortran
testcase).
Richard.
2016-09-21 Richard Biener <rguent...@suse.de>
PR tree-optimization/77648
* tree-ssa-structalias.c (process_constraint): Handle all DEREF
with complex RHS.
(make_transitive_closure_constraints): Adjust comment.
(make_any_offset_constraints): New function.
(handle_rhs_call): Make sure to first expand a pointer to all
subfields before transitively closing it.
(handle_const_call): Likewise. Properly expand returned
pointers as well.
(handle_pure_call): Likewise.
* gcc.dg/torture/pr77648-1.c: New testcase.
* gcc.dg/torture/pr77648-2.c: Likewise.
Index: gcc/tree-ssa-structalias.c
===================================================================
*** gcc/tree-ssa-structalias.c (revision 240255)
--- gcc/tree-ssa-structalias.c (working copy)
*************** process_constraint (constraint_t t)
*** 3010,3016 ****
process_constraint (new_constraint (tmplhs, rhs));
process_constraint (new_constraint (lhs, tmplhs));
}
! else if (rhs.type == ADDRESSOF && lhs.type == DEREF)
{
/* Split into tmp = &rhs, *lhs = tmp */
struct constraint_expr tmplhs;
--- 3010,3016 ----
process_constraint (new_constraint (tmplhs, rhs));
process_constraint (new_constraint (lhs, tmplhs));
}
! else if ((rhs.type != SCALAR || rhs.offset != 0) && lhs.type == DEREF)
{
/* Split into tmp = &rhs, *lhs = tmp */
struct constraint_expr tmplhs;
*************** make_transitive_closure_constraints (var
*** 3747,3753 ****
{
struct constraint_expr lhs, rhs;
! /* VAR = *VAR; */
lhs.type = SCALAR;
lhs.var = vi->id;
lhs.offset = 0;
--- 3747,3753 ----
{
struct constraint_expr lhs, rhs;
! /* VAR = *(VAR + UNKNOWN); */
lhs.type = SCALAR;
lhs.var = vi->id;
lhs.offset = 0;
*************** make_transitive_closure_constraints (var
*** 3757,3762 ****
--- 3757,3779 ----
process_constraint (new_constraint (lhs, rhs));
}
+ /* Add constraints to that the solution of VI has all subvariables added. */
+
+ static void
+ make_any_offset_constraints (varinfo_t vi)
+ {
+ struct constraint_expr lhs, rhs;
+
+ /* VAR = VAR + UNKNOWN; */
+ lhs.type = SCALAR;
+ lhs.var = vi->id;
+ lhs.offset = 0;
+ rhs.type = SCALAR;
+ rhs.var = vi->id;
+ rhs.offset = UNKNOWN_OFFSET;
+ process_constraint (new_constraint (lhs, rhs));
+ }
+
/* Temporary storage for fake var decls. */
struct obstack fake_var_decl_obstack;
*************** handle_rhs_call (gcall *stmt, vec<ce_s>
*** 3902,3916 ****
&& (flags & EAF_NOESCAPE))
{
varinfo_t uses = get_call_use_vi (stmt);
if (!(flags & EAF_DIRECT))
! {
! varinfo_t tem = new_var_info (NULL_TREE, "callarg", true);
! make_constraint_to (tem->id, arg);
! make_transitive_closure_constraints (tem);
! make_copy_constraint (uses, tem->id);
! }
! else
! make_constraint_to (uses->id, arg);
returns_uses = true;
}
else if (flags & EAF_NOESCAPE)
--- 3919,3930 ----
&& (flags & EAF_NOESCAPE))
{
varinfo_t uses = get_call_use_vi (stmt);
+ varinfo_t tem = new_var_info (NULL_TREE, "callarg", true);
+ make_constraint_to (tem->id, arg);
+ make_any_offset_constraints (tem);
if (!(flags & EAF_DIRECT))
! make_transitive_closure_constraints (tem);
! make_copy_constraint (uses, tem->id);
returns_uses = true;
}
else if (flags & EAF_NOESCAPE)
*************** handle_rhs_call (gcall *stmt, vec<ce_s>
*** 3920,3925 ****
--- 3934,3940 ----
varinfo_t clobbers = get_call_clobber_vi (stmt);
varinfo_t tem = new_var_info (NULL_TREE, "callarg", true);
make_constraint_to (tem->id, arg);
+ make_any_offset_constraints (tem);
if (!(flags & EAF_DIRECT))
make_transitive_closure_constraints (tem);
make_copy_constraint (uses, tem->id);
*************** handle_rhs_call (gcall *stmt, vec<ce_s>
*** 3945,3951 ****
if (returns_uses)
{
rhsc.var = get_call_use_vi (stmt)->id;
! rhsc.offset = 0;
rhsc.type = SCALAR;
results->safe_push (rhsc);
}
--- 3960,3966 ----
if (returns_uses)
{
rhsc.var = get_call_use_vi (stmt)->id;
! rhsc.offset = UNKNOWN_OFFSET;
rhsc.type = SCALAR;
results->safe_push (rhsc);
}
*************** handle_const_call (gcall *stmt, vec<ce_s
*** 4054,4059 ****
--- 4069,4075 ----
if (gimple_call_chain (stmt))
{
varinfo_t uses = get_call_use_vi (stmt);
+ make_any_offset_constraints (uses);
make_transitive_closure_constraints (uses);
make_constraint_to (uses->id, gimple_call_chain (stmt));
rhsc.var = uses->id;
*************** handle_const_call (gcall *stmt, vec<ce_s
*** 4062,4077 ****
results->safe_push (rhsc);
}
! /* May return arguments. */
for (k = 0; k < gimple_call_num_args (stmt); ++k)
{
tree arg = gimple_call_arg (stmt, k);
auto_vec<ce_s> argc;
- unsigned i;
- struct constraint_expr *argp;
get_constraint_for_rhs (arg, &argc);
! FOR_EACH_VEC_ELT (argc, i, argp)
! results->safe_push (*argp);
}
/* May return addresses of globals. */
--- 4078,4101 ----
results->safe_push (rhsc);
}
! /* May return offsetted arguments. */
! varinfo_t tem = NULL;
! if (gimple_call_num_args (stmt) != 0)
! tem = new_var_info (NULL_TREE, "callarg", true);
for (k = 0; k < gimple_call_num_args (stmt); ++k)
{
tree arg = gimple_call_arg (stmt, k);
auto_vec<ce_s> argc;
get_constraint_for_rhs (arg, &argc);
! make_constraints_to (tem->id, argc);
! }
! if (tem)
! {
! ce_s ce;
! ce.type = SCALAR;
! ce.var = tem->id;
! ce.offset = UNKNOWN_OFFSET;
! results->safe_push (ce);
}
/* May return addresses of globals. */
*************** handle_pure_call (gcall *stmt, vec<ce_s>
*** 4098,4103 ****
--- 4122,4128 ----
if (!uses)
{
uses = get_call_use_vi (stmt);
+ make_any_offset_constraints (uses);
make_transitive_closure_constraints (uses);
}
make_constraint_to (uses->id, arg);
*************** handle_pure_call (gcall *stmt, vec<ce_s>
*** 4109,4114 ****
--- 4134,4140 ----
if (!uses)
{
uses = get_call_use_vi (stmt);
+ make_any_offset_constraints (uses);
make_transitive_closure_constraints (uses);
}
make_constraint_to (uses->id, gimple_call_chain (stmt));
Index: gcc/testsuite/gcc.dg/torture/pr77648-1.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr77648-1.c (revision 0)
--- gcc/testsuite/gcc.dg/torture/pr77648-1.c (working copy)
***************
*** 0 ****
--- 1,24 ----
+ /* { dg-do run } */
+
+ struct S { int *p; int *q; };
+
+ int **__attribute__((noinline,noclone,pure)) foo (struct S *s)
+ {
+ int tem;
+ __asm__ ("" : "=g" (tem) : "g" (s->p));
+ return &s->q;
+ }
+
+ int main()
+ {
+ struct S s;
+ int i = 1, j = 2;
+ int **x;
+ s.p = &i;
+ s.q = &j;
+ x = foo (&s);
+ **x = 7;
+ if (j != 7)
+ __builtin_abort ();
+ return 0;
+ }
Index: gcc/testsuite/gcc.dg/torture/pr77648-2.c
===================================================================
*** gcc/testsuite/gcc.dg/torture/pr77648-2.c (revision 0)
--- gcc/testsuite/gcc.dg/torture/pr77648-2.c (working copy)
***************
*** 0 ****
--- 1,22 ----
+ /* { dg-do run } */
+
+ struct S { int *p; int *q; };
+
+ int **__attribute__((noinline,noclone,const)) foo (struct S *s)
+ {
+ return &s->q;
+ }
+
+ int main()
+ {
+ struct S s;
+ int i = 1, j = 2;
+ int **x;
+ s.p = &i;
+ s.q = &j;
+ x = foo (&s);
+ **x = 7;
+ if (j != 7)
+ __builtin_abort ();
+ return 0;
+ }
