Hi
in a patch I work on I store ipa_polymorphic_call_contexts in a vector
and thus they do not get properly constructed, merely memset to zero.
This means that I happen to be using "know nothing" contexts which
have their outer_type set to NULL but the various flags are also
false, unlike in the properly constructed ones.
When I pass such context to possible_polymorphic_call_targets, I get
wrong complete results of size one because it sets the outer_type to
otr_type but leaves the maybe_derived_type flag cleared. So I changed
the function to reset the context using clear_outer_type(otr_type)
instead, which I believe is the proper way of doing it. However, I
had to make that method public to do so.
Bootstrapped and tested on x86_64-linux. OK for trunk?
Thanks,
Martin
2014-11-08 Martin Jambor <mjam...@suse.cz>
* cgraph.h (clear_outer_type): Make public. Fix comment.
* ipa-devirt.c (possible_polymorphic_call_targets): Use
clear_outer_type when resetting the context.
Index: src/gcc/cgraph.h
===================================================================
--- src.orig/gcc/cgraph.h 2014-11-05 17:12:51.284464567 +0100
+++ src/gcc/cgraph.h 2014-11-08 19:53:22.726610625 +0100
@@ -1334,6 +1334,10 @@ public:
/* Make context non-speculative. */
void clear_speculation ();
+ /* Produce context specifying all derrived types of OTR_TYPE. If OTR_TYPE is
+ NULL, the context is set to dummy "I know nothing" setting. */
+ void clear_outer_type (tree otr_type = NULL);
+
/* Walk container types and modify context to point to actual class
containing OTR_TYPE (if non-NULL) as base class.
Return true if resulting context is valid.
@@ -1374,7 +1378,6 @@ private:
bool combine_speculation_with (tree, HOST_WIDE_INT, bool, tree);
void set_by_decl (tree, HOST_WIDE_INT);
bool set_by_invariant (tree, tree, HOST_WIDE_INT);
- void clear_outer_type (tree otr_type = NULL);
bool speculation_consistent_p (tree, HOST_WIDE_INT, bool, tree);
void make_speculative (tree otr_type = NULL);
};
@@ -2724,9 +2727,8 @@ ipa_polymorphic_call_context::clear_spec
speculative_maybe_derived_type = false;
}
-/* Produce context specifying all derrived types of OTR_TYPE.
- If OTR_TYPE is NULL or type of the OBJ_TYPE_REF, the context is set
- to dummy "I know nothing" setting. */
+/* Produce context specifying all derrived types of OTR_TYPE. If OTR_TYPE is
+ NULL, the context is set to dummy "I know nothing" setting. */
inline void
ipa_polymorphic_call_context::clear_outer_type (tree otr_type)
Index: src/gcc/ipa-devirt.c
===================================================================
--- src.orig/gcc/ipa-devirt.c 2014-11-03 20:17:30.200011833 +0100
+++ src/gcc/ipa-devirt.c 2014-11-08 19:48:47.882600150 +0100
@@ -2281,10 +2281,7 @@ possible_polymorphic_call_targets (tree
/* Without outer type, we have no use for offset. Just do the
basic search from innter type */
if (!context.outer_type)
- {
- context.outer_type = otr_type;
- context.offset = 0;
- }
+ context.clear_outer_type (otr_type);
/* We need to update our hiearchy if the type does not exist. */
outer_type = get_odr_type (context.outer_type, true);
/* If the type is complete, there are no derivations. */
