From: Stefan Schulze Frielinghaus <stefansf@gcc.gnu.org>
Date: Fri, 27 Sep 2024 10:45:42 +0000 (+0200)
Subject: s390: Fix AQ and AR constraints
X-Git-Tag: releases/gcc-12.5.0~533
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=8d29e1c4ceaea4d3ceec6b51de5b7c31a6bc5f85;p=thirdparty%2Fgcc.git

s390: Fix AQ and AR constraints

Ensure for AQ and AR constraints that the resulting displacement after
adding any positive offset less than the size of the object being
referenced is still valid.

gcc/ChangeLog:

	* config/s390/s390.cc (s390_mem_constraint): Check displacement
	for AQ and AR constraints.

(cherry picked from commit 1a71ff3b89aadc7fa0af0bca269d74bb23c1a957)
---

diff --git a/gcc/config/s390/s390.cc b/gcc/config/s390/s390.cc
index b66fc5be8719..2be3a873b891 100644
--- a/gcc/config/s390/s390.cc
+++ b/gcc/config/s390/s390.cc
@@ -3405,6 +3405,18 @@ s390_mem_constraint (const char *str, rtx op)
       if ((reload_completed || reload_in_progress)
 	  ? !offsettable_memref_p (op) : !offsettable_nonstrict_memref_p (op))
 	return 0;
+      /* offsettable_memref_p ensures only that any positive offset added to
+	 the address forms a valid general address.  For AQ and AR constraints
+	 we also have to verify that the resulting displacement after adding
+	 any positive offset less than the size of the object being referenced
+	 is still valid.  */
+      if (str[1] == 'Q' || str[1] == 'R')
+	{
+	  int o = GET_MODE_SIZE (GET_MODE (op)) - 1;
+	  rtx tmp = adjust_address (op, QImode, o);
+	  if (!s390_check_qrst_address (str[1], XEXP (tmp, 0), true))
+	    return 0;
+	}
       return s390_check_qrst_address (str[1], XEXP (op, 0), true);
     case 'B':
       /* Check for non-literal-pool variants of memory constraints.  */