From patchwork Thu Jul 4 04:55:02 2019 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Kevin Buettner X-Patchwork-Id: 33528 Received: (qmail 62114 invoked by alias); 4 Jul 2019 05:05:23 -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 62094 invoked by uid 89); 4 Jul 2019 05:05:23 -0000 Authentication-Results: sourceware.org; auth=none X-Spam-SWARE-Status: No, score=-16.6 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, SPF_HELO_PASS autolearn=ham version=3.3.1 spammy=UD:style X-HELO: mx1.redhat.com Received: from mx1.redhat.com (HELO mx1.redhat.com) (209.132.183.28) by sourceware.org (qpsmtpd/0.93/v0.84-503-g423c35a) with ESMTP; Thu, 04 Jul 2019 05:03:40 +0000 Received: from smtp.corp.redhat.com (int-mx04.intmail.prod.int.phx2.redhat.com [10.5.11.14]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by mx1.redhat.com (Postfix) with ESMTPS id 04D8B59442 for ; Thu, 4 Jul 2019 04:55:36 +0000 (UTC) Received: from f30-1.lan (ovpn-117-224.phx2.redhat.com [10.3.117.224]) by smtp.corp.redhat.com (Postfix) with ESMTP id CA39D8351E; Thu, 4 Jul 2019 04:55:35 +0000 (UTC) From: Kevin Buettner To: gdb-patches@sourceware.org Cc: Kevin Buettner Subject: [PATCH v2 4/5] Allow display of negative offsets in print_address_symbolic() Date: Wed, 3 Jul 2019 21:55:02 -0700 Message-Id: <20190704045503.1250-5-kevinb@redhat.com> In-Reply-To: <20190704045503.1250-1-kevinb@redhat.com> References: <20190704045503.1250-1-kevinb@redhat.com> MIME-Version: 1.0 X-IsSubscribed: yes When examining addresses associated with blocks with non-contiguous address ranges, it's not uncommon to see large positive offsets which, for some address width, actually represent a smaller negative offset. Here's an example taken from the test case (using the dw2-ranges-func-lo-cold executable): (gdb) x/5i foo_cold 0x40110d : push %rbp 0x40110e : mov %rsp,%rbp 0x401111 : callq 0x401106 0x401116 : nop 0x401117 : pop %rbp This commit, in conjuction with an earlier patch from this series, causes cases like the above to be displayed like this (below) instead: (gdb) x/5i foo_cold 0x40110d : push %rbp 0x40110e : mov %rsp,%rbp 0x401111 : callq 0x401106 0x401116 : nop 0x401117 : pop %rbp Note that the address of foo_cold is now (due to another patch) being displayed as instead of . The subsequent lines are shown as negative offsets from foo. Disassembly using the "disassemble" command is somewhat affected by these changes: Before: (gdb) disassemble foo_cold Dump of assembler code for function foo: Address range 0x401120 to 0x40113b: 0x0000000000401120 <+0>: push %rbp 0x0000000000401121 <+1>: mov %rsp,%rbp 0x0000000000401124 <+4>: callq 0x401119 0x0000000000401129 <+9>: mov 0x2ef1(%rip),%eax # 0x404020 0x000000000040112f <+15>: test %eax,%eax 0x0000000000401131 <+17>: je 0x401138 0x0000000000401133 <+19>: callq 0x40110d 0x0000000000401138 <+24>: nop 0x0000000000401139 <+25>: pop %rbp 0x000000000040113a <+26>: retq Address range 0x40110d to 0x401119: 0x000000000040110d <+-19>: push %rbp 0x000000000040110e <+-18>: mov %rsp,%rbp 0x0000000000401111 <+-15>: callq 0x401106 0x0000000000401116 <+-10>: nop 0x0000000000401117 <+-9>: pop %rbp 0x0000000000401118 <+-8>: retq End of assembler dump. After: (gdb) disassemble foo_cold Dump of assembler code for function foo: Address range 0x401120 to 0x40113b: 0x0000000000401120 <+0>: push %rbp 0x0000000000401121 <+1>: mov %rsp,%rbp 0x0000000000401124 <+4>: callq 0x401119 0x0000000000401129 <+9>: mov 0x2ef1(%rip),%eax # 0x404020 0x000000000040112f <+15>: test %eax,%eax 0x0000000000401131 <+17>: je 0x401138 0x0000000000401133 <+19>: callq 0x40110d 0x0000000000401138 <+24>: nop 0x0000000000401139 <+25>: pop %rbp 0x000000000040113a <+26>: retq Address range 0x40110d to 0x401119: 0x000000000040110d <-19>: push %rbp 0x000000000040110e <-18>: mov %rsp,%rbp 0x0000000000401111 <-15>: callq 0x401106 0x0000000000401116 <-10>: nop 0x0000000000401117 <-9>: pop %rbp 0x0000000000401118 <-8>: retq End of assembler dump. Note that negative offsets are now displayed without the leading "+". Also, the callq to foo_cold is now displayed as such instead of a callq to foo with a large positive offset. gdb/ChangeLog: * printcmd.c (print_address_symbolic): Print negative offsets. (build_address_symbolic): Force signed arithmetic when computing offset. --- gdb/printcmd.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/gdb/printcmd.c b/gdb/printcmd.c index 1109cb3046..dce6ab2db9 100644 --- a/gdb/printcmd.c +++ b/gdb/printcmd.c @@ -539,7 +539,7 @@ print_address_symbolic (struct gdbarch *gdbarch, CORE_ADDR addr, fputs_filtered ("<", stream); fputs_styled (name.c_str (), function_name_style.style (), stream); if (offset != 0) - fprintf_filtered (stream, "+%u", (unsigned int) offset); + fprintf_filtered (stream, "%+d", offset); /* Append source filename and line number if desired. Give specific line # of this addr, if we have it; else line # of the nearest symbol. */ @@ -679,7 +679,7 @@ build_address_symbolic (struct gdbarch *gdbarch, && name_location + max_symbolic_offset > name_location) return 1; - *offset = addr - name_location; + *offset = (LONGEST) addr - name_location; *name = name_temp;