Hello.
Currently ifunc is interpreted as normal alias by IPA optimizations. That's
problematic
as should not consider ifunc alias as candidate for inlining, or redirection.
Patch can bootstrap on ppc64le-redhat-linux and survives regression tests.
And survives MVC tests on x86_64-linux-gnu.
Ready to be installed?
Martin
gcc/ChangeLog:
2017-06-22 Martin Liska <mli...@suse.cz>
* ipa-inline.c (can_inline_edge_p): Return false for ifunc fns.
* ipa-visibility.c (can_replace_by_local_alias): Likewise.
gcc/c-family/ChangeLog:
2017-06-22 Martin Liska <mli...@suse.cz>
* c-attribs.c (handle_alias_ifunc_attribute): Append ifunc alias
to a function declaration.
gcc/testsuite/ChangeLog:
2017-06-22 Martin Liska <mli...@suse.cz>
* gcc.target/i386/pr81128.c: New test.
---
gcc/c-family/c-attribs.c | 11 ++++--
gcc/ipa-inline.c | 2 +
gcc/ipa-visibility.c | 3 +-
gcc/testsuite/gcc.target/i386/pr81128.c | 65 +++++++++++++++++++++++++++++++++
4 files changed, 77 insertions(+), 4 deletions(-)
create mode 100644 gcc/testsuite/gcc.target/i386/pr81128.c
diff --git a/gcc/c-family/c-attribs.c b/gcc/c-family/c-attribs.c
index 2b6845f2cbd..626ffa1cde7 100644
--- a/gcc/c-family/c-attribs.c
+++ b/gcc/c-family/c-attribs.c
@@ -1846,9 +1846,14 @@ handle_alias_ifunc_attribute (bool is_alias, tree *node, tree name, tree args,
TREE_STATIC (decl) = 1;
if (!is_alias)
- /* ifuncs are also aliases, so set that attribute too. */
- DECL_ATTRIBUTES (decl)
- = tree_cons (get_identifier ("alias"), args, DECL_ATTRIBUTES (decl));
+ {
+ /* ifuncs are also aliases, so set that attribute too. */
+ DECL_ATTRIBUTES (decl)
+ = tree_cons (get_identifier ("alias"), args,
+ DECL_ATTRIBUTES (decl));
+ DECL_ATTRIBUTES (decl) = tree_cons (get_identifier ("ifunc"),
+ NULL, DECL_ATTRIBUTES (decl));
+ }
}
else
{
diff --git a/gcc/ipa-inline.c b/gcc/ipa-inline.c
index fb20d3723cc..588fa9c41e4 100644
--- a/gcc/ipa-inline.c
+++ b/gcc/ipa-inline.c
@@ -370,6 +370,8 @@ can_inline_edge_p (struct cgraph_edge *e, bool report,
e->inline_failed = CIF_ATTRIBUTE_MISMATCH;
inlinable = false;
}
+ else if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (e->callee->decl)))
+ inlinable = false;
/* Check if caller growth allows the inlining. */
else if (!DECL_DISREGARD_INLINE_LIMITS (callee->decl)
&& !disregard_limits
diff --git a/gcc/ipa-visibility.c b/gcc/ipa-visibility.c
index d5a3ae56c46..79d05b41085 100644
--- a/gcc/ipa-visibility.c
+++ b/gcc/ipa-visibility.c
@@ -345,7 +345,8 @@ can_replace_by_local_alias (symtab_node *node)
return (node->get_availability () > AVAIL_INTERPOSABLE
&& !decl_binds_to_current_def_p (node->decl)
- && !node->can_be_discarded_p ());
+ && !node->can_be_discarded_p ()
+ && !lookup_attribute ("ifunc", DECL_ATTRIBUTES (node->decl)));
}
/* Return true if we can replace reference to NODE by local alias
diff --git a/gcc/testsuite/gcc.target/i386/pr81128.c b/gcc/testsuite/gcc.target/i386/pr81128.c
new file mode 100644
index 00000000000..90a567ad690
--- /dev/null
+++ b/gcc/testsuite/gcc.target/i386/pr81128.c
@@ -0,0 +1,65 @@
+/* PR ipa/81128 */
+/* { dg-do run } */
+/* { dg-options "-O3" } */
+/* { dg-require-ifunc "" } */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <time.h>
+
+int resolver_fn = 0;
+int resolved_fn = 0;
+
+static inline void
+do_it_right_at_runtime_A ()
+{
+ resolved_fn++;
+}
+
+static inline void
+do_it_right_at_runtime_B ()
+{
+ resolved_fn++;
+}
+
+static inline void do_it_right_at_runtime (void);
+
+void do_it_right_at_runtime (void)
+ __attribute__ ((ifunc ("resolve_do_it_right_at_runtime")));
+
+static void (*resolve_do_it_right_at_runtime (void)) (void)
+{
+ srand (time (NULL));
+ int r = rand ();
+ resolver_fn++;
+
+ /* Use intermediate variable to get a warning for non-matching
+ * prototype. */
+ typeof(do_it_right_at_runtime) *func;
+ if (r & 1)
+ func = do_it_right_at_runtime_A;
+ else
+ func = do_it_right_at_runtime_B;
+
+ return (void *) func;
+}
+
+int
+main (void)
+{
+ const unsigned int ITERS = 10;
+
+ for (int i = ITERS; i > 0; i--)
+ {
+ do_it_right_at_runtime ();
+ }
+
+ if (resolver_fn != 1)
+ __builtin_abort ();
+
+ if (resolved_fn != 10)
+ __builtin_abort ();
+
+ return 0;
+}
