From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by sourceware.org (Postfix) with ESMTPS id 448983858C00 for ; Thu, 19 Jan 2023 10:46:20 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 448983858C00 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 8183F5CC63; Thu, 19 Jan 2023 10:46:19 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1674125179; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lzo28Hz/G3X51TIg6UAD/kGcnroG0zrSuECkuNpugY8=; b=aVq1D2ek74BEYGZwsfw2mviBM4eobB6Ln855v6th3bTHdk5ZaVYakgtgOaH1OXjLB85mhq qwJDx0ctlSZyM7AXkk2gqwpY3f/A2QAImfc/2eoq9PSISOBi904Abd/F1Lnq0WL3L0t5pq vKLx8oX594zWDeC7HtqqjN6Ypq8eDTo= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1674125179; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=lzo28Hz/G3X51TIg6UAD/kGcnroG0zrSuECkuNpugY8=; b=U2ygAVfjnRHPC8TcTIqw27rfIJHnRoebJABRvj9YPlWKTxJ3dgp7dEEtVGF74sgrB3ZCXl KvcPjgWU5PBflyCA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 61890139ED; Thu, 19 Jan 2023 10:46:19 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id iHu4FnsfyWOMJwAAMHmgww (envelope-from ); Thu, 19 Jan 2023 10:46:19 +0000 From: Tom de Vries To: gdb-patches@sourceware.org Cc: Bruno Larsen , Andrew Burgess , Luis Machado Subject: [PATCH 3/4] [gdb/tdep, aarch64] Fix frame address of last insn in leaf function Date: Thu, 19 Jan 2023 11:46:17 +0100 Message-Id: <20230119104618.15503-4-tdevries@suse.de> X-Mailer: git-send-email 2.35.3 In-Reply-To: <20230119104618.15503-1-tdevries@suse.de> References: <20230119104618.15503-1-tdevries@suse.de> MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: Consider the test-case test.c, compiled without debug info: ... void foo (const char *s) { } int main (void) { foo ("foo"); return 0; } ... Disassembly of foo: ... 0000000000400564 : 400564: d10043ff sub sp, sp, #0x10 400568: f90007e0 str x0, [sp, #8] 40056c: d503201f nop 400570: 910043ff add sp, sp, #0x10 400574: d65f03c0 ret ... Now, let's do "info frame" at each insn in foo, as well as printing $sp and $x29 (and strip the output of info frame to the first line, for brevity): ... $ gdb -q a.out Reading symbols from a.out... (gdb) b *foo Breakpoint 1 at 0x400564 (gdb) r Starting program: a.out Breakpoint 1, 0x0000000000400564 in foo () (gdb) display /x $sp 1: /x $sp = 0xfffffffff3a0 (gdb) display /x $x29 2: /x $x29 = 0xfffffffff3a0 (gdb) info frame Stack level 0, frame at 0xfffffffff3a0: (gdb) si 0x0000000000400568 in foo () 1: /x $sp = 0xfffffffff390 2: /x $x29 = 0xfffffffff3a0 (gdb) info frame Stack level 0, frame at 0xfffffffff3a0: (gdb) si 0x000000000040056c in foo () 1: /x $sp = 0xfffffffff390 2: /x $x29 = 0xfffffffff3a0 (gdb) info frame Stack level 0, frame at 0xfffffffff3a0: (gdb) si 0x0000000000400570 in foo () 1: /x $sp = 0xfffffffff390 2: /x $x29 = 0xfffffffff3a0 (gdb) info frame Stack level 0, frame at 0xfffffffff3a0: (gdb) si 0x0000000000400574 in foo () 1: /x $sp = 0xfffffffff3a0 2: /x $x29 = 0xfffffffff3a0 (gdb) info frame Stack level 0, frame at 0xfffffffff3b0: pc = 0x400574 in foo; saved pc = 0x40058c (gdb) si 0x000000000040058c in main () 1: /x $sp = 0xfffffffff3a0 2: /x $x29 = 0xfffffffff3a0 ... The "frame at" bit lists 0xfffffffff3a0 except at the last insn, where it lists 0xfffffffff3b0. The frame address is calculated here in aarch64_make_prologue_cache_1: ... unwound_fp = get_frame_register_unsigned (this_frame, cache->framereg); if (unwound_fp == 0) return; cache->prev_sp = unwound_fp + cache->framesize; ... For insns after the prologue, we have cache->framereg == sp and cache->framesize == 16, so unwound_fp + cache->framesize gives the wrong answer once sp has been restored to entry value by the before-last insn. Fix this by detecting the situation that the sp has been restored. This fixes PR tdep/30011. This also fixes the aarch64 FAILs in gdb.reverse/solib-precsave.exp and gdb.reverse/solib-reverse.exp I reported in PR gdb/PR29721. Tested on aarch64-linux. PR tdep/30011 Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=30011 --- gdb/aarch64-tdep.c | 6 +++++- 1 file changed, 5 insertions(+), 1 deletion(-) diff --git a/gdb/aarch64-tdep.c b/gdb/aarch64-tdep.c index b576d3b9d99..06349353716 100644 --- a/gdb/aarch64-tdep.c +++ b/gdb/aarch64-tdep.c @@ -996,7 +996,11 @@ aarch64_make_prologue_cache_1 (frame_info_ptr this_frame, if (unwound_fp == 0) return; - cache->prev_sp = unwound_fp + cache->framesize; + if (cache->framereg == AARCH64_SP_REGNUM + && get_frame_register_unsigned (this_frame, AARCH64_FP_REGNUM) == unwound_fp) + cache->prev_sp = unwound_fp; + else + cache->prev_sp = unwound_fp + cache->framesize; /* Calculate actual addresses of saved registers using offsets determined by aarch64_analyze_prologue. */ -- 2.35.3