On Wed, Feb 05, 2014 at 02:20:05PM +0100, Richard Biener wrote:
> > Using !!optimize to determine if we should switch local ABI to regparm
> > convention isn't compatible with optimize attribute, as !!optimize is
> > whether the current function is being optimized, but for the ABI decisions
> > we actually need the caller and callee to agree on the calling convention.
> >
> > Fixed by looking at callee's optimize settings all the time.
> >
> > Bootstrapped/regtested on x86_64-linux and i686-linux, ok for trunk?
>
> Seeing a 2nd variant of such code I'd rather have an abstraction
> for this ... optimize_fn ()? opt_for_fn (fn, OPT_...)?
Here is an updated version of the patch, unfortunately this one regressed in
quite a lot of tests. The problem is that by using opt_for_fn there
it also sets the failure reason for all functions at -O0 that don't have
the optimize attribute at all. Now copy_forbidden is used by the inliner,
where we have to handle always_inline functions, other -O0 functions we likely
don't want to inline, be it because the cmd line options are -O0 or because
the function we are considering for inlining has optimize (0), and
for versioning, where I'd say we want to never version the -O0 functions.
So, where do we want to do that instead? E.g. should it be e.g. in
tree_versionable_function_p directly and let the inliner (if it doesn't do
already) also treat optimize(0) functions that aren't always_inline as
noinline?
I guess even without this patch my PR60026 fix broke inlining of
__attribute__((always_inline, optimize (0))) functions.
2014-02-05 Jakub Jelinek <ja...@redhat.com>
PR target/60062
* tree.h (opts_for_fn): New inline function.
(opt_for_fn): Define.
* config/i386/i386.c (ix86_function_regparm): Use
opt_for_fn (decl, optimize) instead of optimize.
* tree-inline.c (copy_forbidden): Use opt_for_fn.
* gcc.c-torture/execute/pr60062.c: New test.
* gcc.c-torture/execute/pr60072.c: New test.
--- gcc/tree.h.jj 2014-01-20 19:16:29.000000000 +0100
+++ gcc/tree.h 2014-02-05 15:54:04.681904492 +0100
@@ -4470,6 +4470,20 @@ may_be_aliased (const_tree var)
|| TREE_ADDRESSABLE (var)));
}
+/* Return pointer to optimization flags of FNDECL. */
+static inline struct cl_optimization *
+opts_for_fn (const_tree fndecl)
+{
+ tree fn_opts = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fndecl);
+ if (fn_opts == NULL_TREE)
+ fn_opts = optimization_default_node;
+ return TREE_OPTIMIZATION (fn_opts);
+}
+
+/* opt flag for function FNDECL, e.g. opts_for_fn (fndecl, optimize) is
+ the optimization level of function fndecl. */
+#define opt_for_fn(fndecl, opt) (opts_for_fn (fndecl)->x_##opt)
+
/* For anonymous aggregate types, we need some sort of name to
hold on to. In practice, this should not appear, but it should
not be harmful if it does. */
--- gcc/config/i386/i386.c.jj 2014-02-05 10:37:36.166167116 +0100
+++ gcc/config/i386/i386.c 2014-02-05 15:56:36.779146394 +0100
@@ -5608,7 +5608,12 @@ ix86_function_regparm (const_tree type,
/* Use register calling convention for local functions when possible. */
if (decl
&& TREE_CODE (decl) == FUNCTION_DECL
- && optimize
+ /* Caller and callee must agree on the calling convention, so
+ checking here just optimize means that with
+ __attribute__((optimize (...))) caller could use regparm convention
+ and callee not, or vice versa. Instead look at whether the callee
+ is optimized or not. */
+ && opt_for_fn (decl, optimize)
&& !(profile_flag && !flag_fentry))
{
/* FIXME: remove this CONST_CAST when cgraph.[ch] is constified. */
--- gcc/tree-inline.c.jj 2014-02-04 14:03:31.000000000 +0100
+++ gcc/tree-inline.c 2014-02-05 15:55:34.747448968 +0100
@@ -3315,16 +3315,10 @@ copy_forbidden (struct function *fun, tr
goto fail;
}
- tree fs_opts;
- fs_opts = DECL_FUNCTION_SPECIFIC_OPTIMIZATION (fun->decl);
- if (fs_opts)
+ if (!opt_for_fn (fun->decl, optimize))
{
- struct cl_optimization *os = TREE_OPTIMIZATION (fs_opts);
- if (!os->x_optimize)
- {
- reason = G_("function %q+F compiled without optimizations");
- goto fail;
- }
+ reason = G_("function %q+F compiled without optimizations");
+ goto fail;
}
fail:
--- gcc/testsuite/gcc.c-torture/execute/pr60062.c.jj 2014-02-05
15:55:48.639388697 +0100
+++ gcc/testsuite/gcc.c-torture/execute/pr60062.c 2014-02-05
15:55:48.639388697 +0100
@@ -0,0 +1,25 @@
+/* PR target/60062 */
+
+int a;
+
+static void
+foo (const char *p1, int p2)
+{
+ if (__builtin_strcmp (p1, "hello") != 0)
+ __builtin_abort ();
+}
+
+static void
+bar (const char *p1)
+{
+ if (__builtin_strcmp (p1, "hello") != 0)
+ __builtin_abort ();
+}
+
+__attribute__((optimize (0))) int
+main ()
+{
+ foo ("hello", a);
+ bar ("hello");
+ return 0;
+}
--- gcc/testsuite/gcc.c-torture/execute/pr60072.c.jj 2014-02-05
15:55:48.640388641 +0100
+++ gcc/testsuite/gcc.c-torture/execute/pr60072.c 2014-02-05
15:55:48.640388641 +0100
@@ -0,0 +1,16 @@
+/* PR target/60072 */
+
+int c = 1;
+
+__attribute__ ((optimize (1)))
+static int *foo (int *p)
+{
+ return p;
+}
+
+int
+main ()
+{
+ *foo (&c) = 2;
+ return c - 2;
+}
Jakub
