This fixes a bug in how we treat EAF_NOESCAPE function arguments
in points-to analysis. We forgot to mark them clobbered (ugh).
To retain optimization we need to transitively close arguments
separately after this patch, thus this is what is done.
Bootstrapped on x86_64-unknown-linux-gnu, testing in progress.
Richard.
2012-09-07 Richard Guenther <rguent...@suse.de>
PR middle-end/53667
* tree-ssa-structalias.c (handle_rhs_call): Properly clobber
EAF_NOESCAPED arguments. Transitively close non-EAF_DIRECT
arguments separately.
Index: gcc/tree-ssa-structalias.c
===================================================================
--- gcc/tree-ssa-structalias.c (revision 191016)
+++ gcc/tree-ssa-structalias.c (working copy)
@@ -3735,29 +3735,43 @@ handle_rhs_call (gimple stmt, VEC(ce_s,
/* As we compute ESCAPED context-insensitive we do not gain
any precision with just EAF_NOCLOBBER but not EAF_NOESCAPE
set. The argument would still get clobbered through the
- escape solution.
- ??? We might get away with less (and more precise) constraints
- if using a temporary for transitively closing things. */
+ escape solution. */
if ((flags & EAF_NOCLOBBER)
&& (flags & EAF_NOESCAPE))
{
varinfo_t uses = get_call_use_vi (stmt);
if (!(flags & EAF_DIRECT))
- make_transitive_closure_constraints (uses);
- make_constraint_to (uses->id, arg);
+ {
+ varinfo_t tem = new_var_info (NULL_TREE, "callarg");
+ 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)
{
+ struct constraint_expr lhs, rhs;
varinfo_t uses = get_call_use_vi (stmt);
varinfo_t clobbers = get_call_clobber_vi (stmt);
+ varinfo_t tem = new_var_info (NULL_TREE, "callarg");
+ make_constraint_to (tem->id, arg);
if (!(flags & EAF_DIRECT))
- {
- make_transitive_closure_constraints (uses);
- make_transitive_closure_constraints (clobbers);
- }
- make_constraint_to (uses->id, arg);
- make_constraint_to (clobbers->id, arg);
+ make_transitive_closure_constraints (tem);
+ make_copy_constraint (uses, tem->id);
+ make_copy_constraint (clobbers, tem->id);
+ /* Add *tem = nonlocal, do not add *tem = callused as
+ EAF_NOESCAPE parameters do not escape to other parameters
+ and all other uses appear in NONLOCAL as well. */
+ lhs.type = DEREF;
+ lhs.var = tem->id;
+ lhs.offset = 0;
+ rhs.type = SCALAR;
+ rhs.var = nonlocal_id;
+ rhs.offset = 0;
+ process_constraint (new_constraint (lhs, rhs));
returns_uses = true;
}
else
