On January 29, 2021 9:19:26 PM GMT+01:00, Jakub Jelinek <ja...@redhat.com>
wrote:
>On Fri, Jan 29, 2021 at 11:18:54AM -0800, sunil.k.pandey via
>Gcc-patches wrote:
>> On Linux/x86_64,
>>
>> a7f52181a6a16bb6d216ff41d9c6a9da95c19b5c is the first bad commit
>> commit a7f52181a6a16bb6d216ff41d9c6a9da95c19b5c
>> Author: Richard Biener <rguent...@suse.de>
>> Date: Fri Jan 29 16:02:36 2021 +0100
>>
>> rtl-optimization/98863 - tame i386 specific RPAD pass
>>
>> caused
>>
>> FAIL: gcc.c-torture/compile/20051216-1.c -O1 (internal compiler
>error)
>> FAIL: gcc.c-torture/compile/20051216-1.c -O1 (test for excess
>errors)
>
>I can reproduce it. The problem is that we don't revert the df flags
>back.
>
>The following patch fixes it, ok for trunk if it passes
>bootstrap/regtest?
Hmm, that's odd. Who relies on deferred rescan being the default? Finish pass,
via processing deferred insns also resets it back. Or is this documented
somewhere?
Richard.
>2021-01-29 Jakub Jelinek <ja...@redhat.com>
>
> * config/i386/i386-features.c (remove_partial_avx_dependency):
>Remember
> whether DF_DEFER_INSN_RESCAN has been active before or not, and
> reset it to previous state.
>
> * gcc.target/i386/20051216-1.c: New test.
>
>--- gcc/config/i386/i386-features.c.jj 2021-01-29 20:39:10.561912947
>+0100
>+++ gcc/config/i386/i386-features.c 2021-01-29 20:59:06.254740315 +0100
>@@ -2273,7 +2273,7 @@ remove_partial_avx_dependency (void)
> auto_vec<rtx_insn *> control_flow_insns;
>
> /* We create invalid RTL initially so defer rescans. */
>- df_set_flags (DF_DEFER_INSN_RESCAN);
>+ int prev_df_flags = df_set_flags (DF_DEFER_INSN_RESCAN);
>
> FOR_EACH_BB_FN (bb, cfun)
> {
>@@ -2409,6 +2409,8 @@ remove_partial_avx_dependency (void)
> }
>
> df_process_deferred_rescans ();
>+ if ((prev_df_flags & DF_DEFER_INSN_RESCAN) == 0)
>+ df_clear_flags (DF_DEFER_INSN_RESCAN);
> bitmap_obstack_release (NULL);
> BITMAP_FREE (convert_bbs);
>
>--- gcc/testsuite/gcc.target/i386/20051216-1.c.jj 2021-01-29
>21:06:20.386960652 +0100
>+++ gcc/testsuite/gcc.target/i386/20051216-1.c 2021-01-29
>21:03:17.599973093 +0100
>@@ -0,0 +1,5 @@
>+/* PR rtl-optimization/25432 */
>+/* { dg-do compile } */
>+/* { dg-options "-O1 -march=cascadelake" } */
>+
>+#include "../../gcc.c-torture/compile/20051216-1.c"
>
>
> Jakub
