[gcc r13-3375] s390: Fix bootstrap error with checking and -m31.

[Robin Dapp <rdapp@gcc.gnu.org>]

https://gcc.gnu.org/g:95c5cffb712d90bfe36f2cf71d3a052b8068db34

commit r13-3375-g95c5cffb712d90bfe36f2cf71d3a052b8068db34
Author: Robin Dapp <rdapp@linux.ibm.com>
Date:   Tue Oct 18 12:27:37 2022 +0200

    s390: Fix bootstrap error with checking and -m31.
    
    For a while already we hit an ICE when bootstrapping with -m31 and
    --enable-checking=all.
    
    ../../../../libgfortran/ieee/ieee_helper.c: In function 'ieee_class_helper_16':
    ../../../../libgfortran/ieee/ieee_helper.c:77:3: internal compiler error: RTL check: expected code 'reg', have 'subreg' in rhs_regno, at rtl.h:1932
       77 |   }
          |   ^
    ../../../../libgfortran/ieee/ieee_helper.c:87:1: note: in expansion of macro 'CLASSMACRO'
       87 | CLASSMACRO(16)
          | ^~~~~~~~~~
    
    This patch fixes the problem by first checking for reload_completed
    and also ensuring that REGNO is only called on reg operands rather
    than subregs.
    
    gcc/ChangeLog:
    
            * config/s390/s390.md: Move reload_completed and check operands for REG_P.

Diff:
---
 gcc/config/s390/s390.md | 7 ++++---
 1 file changed, 4 insertions(+), 3 deletions(-)

diff --git a/gcc/config/s390/s390.md b/gcc/config/s390/s390.md
index 962927c3112..c89b15cf4f3 100644
--- a/gcc/config/s390/s390.md
+++ b/gcc/config/s390/s390.md
@@ -8797,9 +8797,10 @@
         (neg:DI (match_operand:DI 1 "register_operand" "")))
    (clobber (reg:CC CC_REGNUM))]
   "!TARGET_ZARCH
-   && (REGNO (operands[0]) == REGNO (operands[1])
-      || s390_split_ok_p (operands[0], operands[1], DImode, 0))
-   && reload_completed"
+   && reload_completed
+   && ((REG_P (operands[0]) && REG_P (operands[1])
+       && REGNO (operands[0]) == REGNO (operands[1]))
+      || s390_split_ok_p (operands[0], operands[1], DImode, 0))"
   [(parallel
     [(set (match_dup 2) (neg:SI (match_dup 3)))
      (clobber (reg:CC CC_REGNUM))])