[PATCH, PR 40570] Do not create cycles of inlined nodes when inlining functions called once

[H.J. Lu]

2009/7/29 Martin Jambor <mjambor@suse.cz>:
> Hi,
>
> I guess the subject says it all.  This fixes PR 40570 by not inlining
> a function into itself, even when it is its own only caller.
>
> Bootstrapped and tested on x86_64-linux but apart from an approval in
> general, I would still like Honza to confirm this is indeed a correct
> fix before committing.
>
> Thanks,
>
> Martin
>
>
>
> 2009-07-28  Martin Jambor  <mjambor@suse.cz>
>
>        * ipa-inline.c (cgraph_decide_inlining): Watch out for dead single
>        use inlining loops.
>
>        * testsuite/gcc.c-torture/compile/pr40570.c: New test.
>

You should mention PR 40570 in both ChangeLog entries.

> Index: icln/gcc/ipa-inline.c
> ===================================================================
> --- icln.orig/gcc/ipa-inline.c
> +++ icln/gcc/ipa-inline.c
> @@ -1227,6 +1227,7 @@ cgraph_decide_inlining (void)
>              && !node->needed
>              && node->local.inlinable
>              && node->callers->inline_failed
> +             && node->callers->caller->global.inlined_to != node
>              && !gimple_call_cannot_inline_p (node->callers->call_stmt)
>              && !DECL_EXTERNAL (node->decl)
>              && !DECL_COMDAT (node->decl))
> Index: icln/gcc/testsuite/gcc.c-torture/compile/pr40570.c
> ===================================================================
> --- /dev/null
> +++ icln/gcc/testsuite/gcc.c-torture/compile/pr40570.c
> @@ -0,0 +1,19 @@
> +static int foo(int i);
> +
> +static int bar(int i) { foo(i); }
> +
> +static int foo(int i)
> +{
> +  int j;
> +  if (j)
> +    FOO(j);

Does it have to be FOO, which is undeclared?

> +  return bar(i);
> +}
> +
> +int baz()
> +{
> +  foo(0);
> +  if (baz())
> +    return 1;
> +  return 0;
> +}
>
>



-- 
H.J.