From: Stefan Schulze Frielinghaus <stefansf@linux.ibm.com>
Date: Thu, 6 Oct 2022 06:43:53 +0000 (+0200)
Subject: cselib: Skip BImode while keeping track of subvalue relations [PR107088]
X-Git-Tag: basepoints/gcc-14~4102
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5fc4d3e1837ea4850aac6460f563913f1d3fc5b8;p=thirdparty%2Fgcc.git

cselib: Skip BImode while keeping track of subvalue relations [PR107088]

For BImode get_narrowest_mode evaluates to QImode but BImode < QImode.
Thus FOR_EACH_MODE_UNTIL never reaches BImode and iterates until OImode
for which no wider mode exists so we end up with VOIDmode and fail.
Fixed by adding a size guard so we effectively skip BImode.

gcc/ChangeLog:

	PR rtl-optimization/107088
	* cselib.cc (new_cselib_val): Skip BImode while keeping track of
	subvalue relations.
---

diff --git a/gcc/cselib.cc b/gcc/cselib.cc
index 9b582e5d3d6d..2abc763a3f8e 100644
--- a/gcc/cselib.cc
+++ b/gcc/cselib.cc
@@ -1571,6 +1571,7 @@ new_cselib_val (unsigned int hash, machine_mode mode, rtx x)
 
   scalar_int_mode int_mode;
   if (REG_P (x) && is_int_mode (mode, &int_mode)
+      && GET_MODE_SIZE (int_mode) > 1
       && REG_VALUES (REGNO (x)) != NULL
       && (!cselib_current_insn || !DEBUG_INSN_P (cselib_current_insn)))
     {