On Fri, Dec 04, 2015 at 10:30:38AM +0100, Richard Biener wrote:
> > The following patch has been bootstrapped/regtested on x86_64-linux and
> > i686-linux.
>
> The patch is ok - it looks like you could have removed the
> __builtin_alloca strcmp with it though.
Ok, will remove the strcmp then.
> Does the patch mean we inlined __builtin_alloca_with_align ()
> functions? We might run into the issue Eric fixed lately with
Yes, see testcase below. 4.7+ inlines it. As for tail call optimization,
seems we are just lucky there (f4), as fab pass which is quite late
turns the __builtin_stack_restore into GIMPLE_NOP and tailc pass does not
ignore nops. Shall I commit following patch to trunk to fix that up
(after committing this VLA fix of course)?
int f1 (char *);
static inline void
f2 (int x)
{
char a[x];
f1 (a);
}
void
f3 (int x)
{
f2 (x);
f2 (x);
f2 (x);
f2 (x);
}
int
f4 (int x)
{
char a[x];
return f1 (a);
}
2015-12-04 Jakub Jelinek <ja...@redhat.com>
* tree-tailcall.c (find_tail_calls): Ignore GIMPLE_NOPs.
--- gcc/tree-tailcall.c.jj 2015-11-04 11:12:17.000000000 +0100
+++ gcc/tree-tailcall.c 2015-12-04 11:43:01.296110941 +0100
@@ -412,9 +412,10 @@ find_tail_calls (basic_block bb, struct
{
stmt = gsi_stmt (gsi);
- /* Ignore labels, returns, clobbers and debug stmts. */
+ /* Ignore labels, returns, nops, clobbers and debug stmts. */
if (gimple_code (stmt) == GIMPLE_LABEL
|| gimple_code (stmt) == GIMPLE_RETURN
+ || gimple_code (stmt) == GIMPLE_NOP
|| gimple_clobber_p (stmt)
|| is_gimple_debug (stmt))
continue;
@@ -532,7 +533,8 @@ find_tail_calls (basic_block bb, struct
stmt = gsi_stmt (agsi);
- if (gimple_code (stmt) == GIMPLE_LABEL)
+ if (gimple_code (stmt) == GIMPLE_LABEL
+ || gimple_code (stmt) == GIMPLE_NOP)
continue;
if (gimple_code (stmt) == GIMPLE_RETURN)
Jakub
