[gcc r11-7725] [PR99422] LRA: Use lookup_constraint only for a single constraint in process_address_1.

[Vladimir Makarov]

https://gcc.gnu.org/g:a4670f58ebff805e35268542aac35f9791980954

commit r11-7725-ga4670f58ebff805e35268542aac35f9791980954
Author: Vladimir N. Makarov <vmakarov@redhat.com>
Date:   Thu Mar 18 15:58:26 2021 -0400

    [PR99422] LRA: Use lookup_constraint only for a single constraint in process_address_1.
    
    This is an additional patch for PR99422.  In process_address_1 we
    look only at the first constraint in the 1st alternative
    and ignore all other possibilities.  As we don't know what
    alternative and constraint will be used at this stage, we can be sure
    only for a single constraint with one alternative and should use unknown
    constraint for all other cases.
    
    gcc/ChangeLog:
    
            PR target/99422
            * lra-constraints.c (process_address_1): Use lookup_constraint
            only for a single constraint.

Diff:
---
 gcc/lra-constraints.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/gcc/lra-constraints.c b/gcc/lra-constraints.c
index 9205826960c..64801b6fcce 100644
--- a/gcc/lra-constraints.c
+++ b/gcc/lra-constraints.c
@@ -3459,7 +3459,12 @@ process_address_1 (int nop, bool check_only_p,
       constraint
 	= skip_contraint_modifiers (curr_static_id->operand[dup].constraint);
     }
-  cn = lookup_constraint (*constraint == '\0' ? "X" : constraint);
+  if (*skip_contraint_modifiers (constraint
+				 + CONSTRAINT_LEN (constraint[0],
+						   constraint)) != '\0')
+    cn = CONSTRAINT__UNKNOWN;
+  else
+    cn = lookup_constraint (*constraint == '\0' ? "X" : constraint);
   if (insn_extra_address_constraint (cn)
       /* When we find an asm operand with an address constraint that
 	 doesn't satisfy address_operand to begin with, we clear