From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (qmail 37765 invoked by alias); 11 Oct 2018 13:39:59 -0000 Mailing-List: contact gcc-patches-help@gcc.gnu.org; run by ezmlm Precedence: bulk List-Id: List-Archive: List-Post: List-Help: Sender: gcc-patches-owner@gcc.gnu.org Received: (qmail 37697 invoked by uid 89); 11 Oct 2018 13:39:58 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-27.6 required=5.0 tests=BAYES_00,GIT_PATCH_0,GIT_PATCH_1,GIT_PATCH_2,GIT_PATCH_3,RCVD_IN_DNSWL_LOW,SPF_PASS autolearn=ham version=3.3.2 spammy= X-HELO: mx07-00178001.pphosted.com Received: from mx07-00178001.pphosted.com (HELO mx07-00178001.pphosted.com) (62.209.51.94) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 11 Oct 2018 13:39:57 +0000 Received: from pps.filterd (m0046668.ppops.net [127.0.0.1]) by mx07-.pphosted.com (8.16.0.21/8.16.0.21) with SMTP id w9BDdKhP016095; Thu, 11 Oct 2018 15:39:55 +0200 Received: from beta.dmz-eu.st.com (beta.dmz-eu.st.com [164.129.1.35]) by mx07-00178001.pphosted.com with ESMTP id 2mxjgy5m9x-1 (version=TLSv1 cipher=ECDHE-RSA-AES256-SHA bits=256 verify=NOT); Thu, 11 Oct 2018 15:39:55 +0200 Received: from zeta.dmz-eu.st.com (zeta.dmz-eu.st.com [164.129.230.9]) by beta.dmz-eu.st.com (STMicroelectronics) with ESMTP id EF64B34; Thu, 11 Oct 2018 13:39:54 +0000 (GMT) Received: from Webmail-eu.st.com (sfhdag5node1.st.com [10.75.127.13]) by zeta.dmz-eu.st.com (STMicroelectronics) with ESMTP id DF347554F; Thu, 11 Oct 2018 13:39:54 +0000 (GMT) Received: from gnb.st.com (10.75.127.45) by SFHDAG5NODE1.st.com (10.75.127.13) with Microsoft SMTP Server (TLS) id 15.0.1347.2; Thu, 11 Oct 2018 15:39:54 +0200 From: Christophe Lyon To: CC: Subject: [ARM/FDPIC v3 13/21] [ARM] FDPIC: Force LSB bit for PC in Cortex-M architecture Date: Thu, 11 Oct 2018 13:40:00 -0000 Message-ID: <20181011133518.17258-14-christophe.lyon@st.com> In-Reply-To: <20181011133518.17258-1-christophe.lyon@st.com> References: <20181011133518.17258-1-christophe.lyon@st.com> MIME-Version: 1.0 Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: 8bit X-IsSubscribed: yes X-SW-Source: 2018-10/txt/msg00648.txt.bz2 Without this, when we are unwinding across a signal frame we can jump to an even address which leads to an exception. This is needed in __gnu_persnality_sigframe_fdpic() when restoring the PC from the signal frame since the PC saved by the kernel has the LSB bit set to zero. 2018-XX-XX Christophe Lyon Mickaël Guêné libgcc/ * config/arm/unwind-arm.c (_Unwind_VRS_Set): Handle v7m architecture. Change-Id: Ie84de548226bcf1751e19a09e8f091fb3013ccea diff --git a/libgcc/config/arm/unwind-arm.c b/libgcc/config/arm/unwind-arm.c index 564e4f13..6da6e3d 100644 --- a/libgcc/config/arm/unwind-arm.c +++ b/libgcc/config/arm/unwind-arm.c @@ -198,6 +198,11 @@ _Unwind_VRS_Result _Unwind_VRS_Set (_Unwind_Context *context, return _UVRSR_FAILED; vrs->core.r[regno] = *(_uw *) valuep; +#if defined(__ARM_ARCH_7M__) + /* Force LSB bit since we always run thumb code. */ + if (regno == 15) + vrs->core.r[regno] |= 1; +#endif return _UVRSR_OK; case _UVRSC_VFP: -- 2.6.3