[gcc(refs/users/giulianob/heads/pfe_backport_clean)] Backport Fix patchable-function-entry on arc

[Giuliano Belinassi <giulianob@gcc.gnu.org>]

https://gcc.gnu.org/g:1b5eac0b3d586f3b51baff5667d903de4a4e06a6

commit 1b5eac0b3d586f3b51baff5667d903de4a4e06a6
Author: Andrew Pinski <apinski@marvell.com>
Date:   Wed Jan 22 23:34:34 2020 +0000

    Backport Fix patchable-function-entry on arc
    
    The problem here is arc looks at current_output_insn unconditional
    but sometimes current_output_insn is NULL.  With patchable-function-entry,
    it will be. This is similar to how the nios2, handles "%.".
    
    Committed as obvious after a simple test with -fpatchable-function-entry=1.
    
    gcc/ChangeLog
    2021-10-07  Giuliano Belinassi  <gbelinassi@suse.de>
    
            Backport from mainline
            2020-01-22  Andrew Pinski  <apinski@marvell.com>
    
            * config/arc/arc.c (output_short_suffix): Check insn for nullness.

Diff:
---
 gcc/config/arc/arc.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/gcc/config/arc/arc.c b/gcc/config/arc/arc.c
index 92fecad93d9..5e92983929d 100644
--- a/gcc/config/arc/arc.c
+++ b/gcc/config/arc/arc.c
@@ -4195,6 +4195,8 @@ static void
 output_short_suffix (FILE *file)
 {
   rtx_insn *insn = current_output_insn;
+  if (!insn)
+    return;
 
   if (arc_verify_short (insn, cfun->machine->unalign, 1))
     {