From patchwork Tue Nov 19 15:14:17 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Simon Marchi (Code Review)" X-Patchwork-Id: 36035 Received: (qmail 66156 invoked by alias); 19 Nov 2019 15:14:24 -0000 Mailing-List: contact gdb-patches-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: gdb-patches-owner@sourceware.org Delivered-To: mailing list gdb-patches@sourceware.org Received: (qmail 66118 invoked by uid 89); 19 Nov 2019 15:14:22 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-26.9 required=5.0 tests=BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3 autolearn=ham version=3.3.1 spammy= X-HELO: mx1.osci.io Received: from polly.osci.io (HELO mx1.osci.io) (8.43.85.229) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Tue, 19 Nov 2019 15:14:21 +0000 Received: by mx1.osci.io (Postfix, from userid 994) id ECBC020373; Tue, 19 Nov 2019 10:14:18 -0500 (EST) Received: from gnutoolchain-gerrit.osci.io (gnutoolchain-gerrit.osci.io [IPv6:2620:52:3:1:5054:ff:fe06:16ca]) by mx1.osci.io (Postfix) with ESMTP id 96722202D0; Tue, 19 Nov 2019 10:14:17 -0500 (EST) Received: from localhost (localhost [127.0.0.1]) by gnutoolchain-gerrit.osci.io (Postfix) with ESMTP id 76C002816F; Tue, 19 Nov 2019 10:14:17 -0500 (EST) X-Gerrit-PatchSet: 4 Date: Tue, 19 Nov 2019 10:14:17 -0500 From: "Luis Machado (Code Review)" To: gdb-patches@sourceware.org Cc: Simon Marchi Auto-Submitted: auto-generated X-Gerrit-MessageType: newpatchset Subject: [review v4] [AArch64, SVE] Improve target description check for SVE in gdbserver X-Gerrit-Change-Id: I28b782cb1677560ca9a06a1be442974b25aabae4 X-Gerrit-Change-Number: 690 X-Gerrit-ChangeURL: X-Gerrit-Commit: d254a84ad6cd999c4830c1fefd4e0583c15f1eac In-Reply-To: References: Reply-To: luis.machado@linaro.org, simon.marchi@polymtl.ca, gdb-patches@sourceware.org MIME-Version: 1.0 Content-Disposition: inline User-Agent: Gerrit/3.0.3-79-g83ff7f88f1 Message-Id: <20191119151417.76C002816F@gnutoolchain-gerrit.osci.io> Change URL: https://gnutoolchain-gerrit.osci.io/r/c/binutils-gdb/+/690 ...................................................................... [AArch64, SVE] Improve target description check for SVE in gdbserver The current code checks for the presence of a SVE target description by comparing the number of registers. This is a bit fragile since the number of registers can change whenever we add new sets. Like PAC, for example. If the comparison breaks, then we're left with SVE registers in the description, but gdbserver doesn't send the registers to GDB, which in turn displays stale information to the user. The following patch changes the check to use the SVE feature string instead, which hopefully should be more stable. gdb/gdbserver/ChangeLog: 2019-11-18 Luis Machado * linux-aarch64-low.c (is_sve_tdesc): Check against target feature instead of register count. * tdesc.c (tdesc_contains_feature): New function. * tdesc.h (tdesc_contains_feature): New prototype. Signed-off-by: Luis Machado Change-Id: I28b782cb1677560ca9a06a1be442974b25aabae4 --- M gdb/gdbserver/linux-aarch64-low.c M gdb/gdbserver/tdesc.c M gdb/gdbserver/tdesc.h 3 files changed, 22 insertions(+), 1 deletion(-) diff --git a/gdb/gdbserver/linux-aarch64-low.c b/gdb/gdbserver/linux-aarch64-low.c index 87a21a0..9e234e0 100644 --- a/gdb/gdbserver/linux-aarch64-low.c +++ b/gdb/gdbserver/linux-aarch64-low.c @@ -83,7 +83,7 @@ { struct regcache *regcache = get_thread_regcache (current_thread, 0); - return regcache->tdesc->reg_defs.size () == AARCH64_SVE_NUM_REGS; + return tdesc_contains_feature (regcache->tdesc, "org.gnu.gdb.aarch64.sve"); } static void diff --git a/gdb/gdbserver/tdesc.c b/gdb/gdbserver/tdesc.c index 92a0a60..817e69a 100644 --- a/gdb/gdbserver/tdesc.c +++ b/gdb/gdbserver/tdesc.c @@ -186,3 +186,19 @@ tdesc->features.emplace_back (new_feature); return new_feature; } + +/* See gdbsupport/tdesc.h. */ + +bool +tdesc_contains_feature (const target_desc *tdesc, const std::string &feature) +{ + gdb_assert (tdesc != nullptr); + + for (const tdesc_feature_up &f : tdesc->features) + { + if (f->name == feature) + return true; + } + + return false; +} diff --git a/gdb/gdbserver/tdesc.h b/gdb/gdbserver/tdesc.h index b93f53c..da21cda 100644 --- a/gdb/gdbserver/tdesc.h +++ b/gdb/gdbserver/tdesc.h @@ -93,4 +93,9 @@ const struct target_desc *current_target_desc (void); +/* Return true if TDESC contains the feature described by string FEATURE. + Return false otherwise. */ +bool tdesc_contains_feature (const target_desc *tdesc, + const std::string &feature); + #endif /* GDBSERVER_TDESC_H */