diff mbox series

s390: Fix AQ and AR constraints

Message ID 20240913055528.3403124-1-stefansf@gcc.gnu.org
State New
Headers show
Series s390: Fix AQ and AR constraints | expand

Commit Message

Stefan Schulze Frielinghaus Sept. 13, 2024, 5:55 a.m. UTC 
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.

Bootstrapped and regtested on s390.  As approved by
https://gcc.gnu.org/pipermail/gcc-patches/2024-September/662865.html
I will push shortly.

gcc/ChangeLog:

	* config/s390/s390.cc (s390_mem_constraint): Check displacement
	for AQ and AR constraints.
---
 gcc/config/s390/s390.cc | 12 ++++++++++++
 1 file changed, 12 insertions(+)
diff mbox series

Patch

diff --git a/gcc/config/s390/s390.cc b/gcc/config/s390/s390.cc
index 7aea776da2f..ae1f369e19d 100644
--- a/gcc/config/s390/s390.cc
+++ b/gcc/config/s390/s390.cc
@@ -3714,6 +3714,18 @@  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.  */