From: Robin Dapp <rdapp@linux.ibm.com>
Date: Tue, 8 Feb 2022 13:39:16 +0000 (+0100)
Subject: combine: Check for paradoxical subreg.
X-Git-Tag: basepoints/gcc-13~1207
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=38a177fa4c2fd1ce75581145b3b8f12592b4aacd;p=thirdparty%2Fgcc.git

combine: Check for paradoxical subreg.

This adds a check for a paradoxical subreg in reg_subword_p ()
in order to prevent an ICE on s390 in try_combine () triggered
by the movqicc expander.

gcc/ChangeLog:

	* combine.cc (reg_subword_p): Check for paradoxical subreg.
---

diff --git a/gcc/combine.cc b/gcc/combine.cc
index 7683f8250fe2..c264ededf20a 100644
--- a/gcc/combine.cc
+++ b/gcc/combine.cc
@@ -2411,6 +2411,7 @@ reg_subword_p (rtx x, rtx reg)
     x = XEXP (x, 0);
 
   return GET_CODE (x) == SUBREG
+	 && !paradoxical_subreg_p (x)
 	 && SUBREG_REG (x) == reg
 	 && GET_MODE_CLASS (GET_MODE (x)) == MODE_INT;
 }