Hi!
While for other -Wsuggest-attribute= cases we only warn if the corresponding
attribute is not present on the current_function_decl, enforced in the
callers of warn_function_*, for the cold attribute warn_function_cold is
called in two places in compute_function_frequency, and in the first one
it is only called when the cold attribute is present on the function.
Fixed thusly, bootstrapped/regtested on x86_64-linux and i686-linux, ok for
trunk?
The only thing I'm unsure about is whether the other warn_function_cold call
in the same function could be reached if current_function_decl has "cold"
attribute; I haven't managed to construct a testcase where it would, so
perhaps further changes aren't needed, but if that spot could be reachable
even with functions declared with cold attribute, perhaps we'd need
if (lookup_attribute ("cold", DECL_ATTRIBTES (current_function_decl)) ==
NULL_TREE)
guarding condition for the other warn_function_cold call.
2020-01-01 Jakub Jelinek <[email protected]>
PR ipa/93087
* predict.c (compute_function_frequency): Don't call
warn_function_cold on functions that already have cold attribute.
* c-c++-common/cold-1.c: New test.
--- gcc/predict.c.jj 2019-12-10 21:34:48.377594665 +0100
+++ gcc/predict.c 2019-12-31 17:01:09.807440029 +0100
@@ -3937,10 +3937,7 @@ compute_function_frequency (void)
int flags = flags_from_decl_or_type (current_function_decl);
if (lookup_attribute ("cold", DECL_ATTRIBUTES (current_function_decl))
!= NULL)
- {
- node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
- warn_function_cold (current_function_decl);
- }
+ node->frequency = NODE_FREQUENCY_UNLIKELY_EXECUTED;
else if (lookup_attribute ("hot", DECL_ATTRIBUTES
(current_function_decl))
!= NULL)
node->frequency = NODE_FREQUENCY_HOT;
--- gcc/testsuite/c-c++-common/cold-1.c.jj 2019-12-31 17:04:35.154357929
+0100
+++ gcc/testsuite/c-c++-common/cold-1.c 2019-12-31 17:03:57.992915598 +0100
@@ -0,0 +1,22 @@
+/* PR ipa/93087 */
+/* { dg-do compile { target nonpic } } */
+/* { dg-options "-O1 -Wsuggest-attribute=cold" } */
+
+extern void *getdata (void);
+extern int set_error (char const *message) __attribute__((cold));
+
+__attribute__((cold)) int
+set_nomem (void) /* { dg-bogus "function might be candidate for
attribute 'cold'" } */
+{
+ return set_error ("Allocation failed");
+}
+
+void *
+getdata_or_set_error (void)
+{
+ void *result;
+ result = getdata ();
+ if (!result)
+ set_nomem ();
+ return result;
+}
Jakub
