From: Segher Boessenkool <segher@kernel.crashing.org>
Date: Wed, 8 Sep 2021 13:10:30 +0000 (+0000)
Subject: rs6000: Fix ELFv2 r12 use in epilogue
X-Git-Tag: releases/gcc-11.3.0~871
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=da0a5628d47ee59320dac9787f3232b0911fbc14;p=thirdparty%2Fgcc.git

rs6000: Fix ELFv2 r12 use in epilogue

We cannot use r12 here, it is already in use as the GEP (for sibling
calls).

2021-09-08  Segher Boessenkool  <segher@kernel.crashing.org>
	PR target/102107
	* config/rs6000/rs6000-logue.c (rs6000_emit_epilogue): For ELFv2 use
	r11 instead of r12 for restoring CR.

(cherry picked from commit 86e6268cff328e27ee6f90e2afc35b6f437a25cd)
---

diff --git a/gcc/config/rs6000/rs6000-logue.c b/gcc/config/rs6000/rs6000-logue.c
index e363d56ecec0..9965a8aa6910 100644
--- a/gcc/config/rs6000/rs6000-logue.c
+++ b/gcc/config/rs6000/rs6000-logue.c
@@ -4815,6 +4815,10 @@ rs6000_emit_epilogue (enum epilogue_type epilogue_type)
       else if (REGNO (frame_reg_rtx) == 12)
 	cr_save_regno = 11;
 
+      /* For ELFv2 r12 is already in use as the GEP.  */
+      if (DEFAULT_ABI == ABI_ELFv2)
+	cr_save_regno = 11;
+
       cr_save_reg = load_cr_save (cr_save_regno, frame_reg_rtx,
 				  info->cr_save_offset + frame_off,
 				  exit_func);