From: Pedro Alves <pedro@palves.net>
To: gdb-patches@sourceware.org
Subject: [PATCH v2 24/29] gdb/testsuite/lib/my-syscalls.S: Refactor new SYSCALL macro
Date: Wed, 13 Jul 2022 23:24:28 +0100 [thread overview]
Message-ID: <20220713222433.374898-25-pedro@palves.net> (raw)
In-Reply-To: <20220713222433.374898-1-pedro@palves.net>
Refactor the syscall assembly code in gdb/testsuite/lib/my-syscalls.S
behind a SYSCALL macro so that it's easy to add new syscalls without
duplicating code.
Note that the way the macro is implemented, it only works correctly
for syscalls with up to 3 arguments, and, if the syscall doesn't
return (the macro doesn't bother to save/restore callee-saved
registers).
The following patch will want to use the macro to define a wrapper for
the "exit" syscall, so the limitations continue to be sufficient.
Change-Id: I8acf1463b11a084d6b4579aaffb49b5d0dea3bba
---
gdb/testsuite/lib/my-syscalls.S | 50 +++++++++++++++++++++------------
1 file changed, 32 insertions(+), 18 deletions(-)
diff --git a/gdb/testsuite/lib/my-syscalls.S b/gdb/testsuite/lib/my-syscalls.S
index 5fc38948217..50544d101e0 100644
--- a/gdb/testsuite/lib/my-syscalls.S
+++ b/gdb/testsuite/lib/my-syscalls.S
@@ -21,36 +21,50 @@
#include <asm/unistd.h>
-/* int my_execve (const char *file, char *argv[], char *envp[]); */
-
-.global my_execve
-my_execve:
+/* The SYSCALL macro below current supports calling syscalls with up
+ to 3 arguments, and, assumes the syscall never returns, like exec
+ and exit. If you need to call syscalls with more arguments or you
+ need to call syscalls that actually return, you'll need to update
+ the macros. We don't bother with optimizing setting up fewer
+ arguments for syscalls that take fewer arguments, as we're not
+ optimizating for speed or space, but for maintainability. */
#if defined(__x86_64__)
- mov $__NR_execve, %rax
- /* rdi, rsi and rdx already contain the right arguments. */
-my_execve_syscall:
- syscall
- ret
+#define SYSCALL(NAME, NR) \
+.global NAME ;\
+NAME: ;\
+ mov $NR, %rax ;\
+ /* rdi, rsi and rdx already contain the right arguments. */ \
+NAME ## _syscall: ;\
+ syscall ;\
+ ret ;
#elif defined(__i386__)
- mov $__NR_execve, %eax
- mov 4(%esp), %ebx
- mov 8(%esp), %ecx
- mov 12(%esp), %edx
-my_execve_syscall:
- int $0x80
+#define SYSCALL(NAME, NR) \
+.global NAME ;\
+NAME: ;\
+ mov $NR, %eax ;\
+ mov 4(%esp), %ebx ;\
+ mov 8(%esp), %ecx ;\
+ mov 12(%esp), %edx ;\
+NAME ## _syscall: ;\
+ int $0x80 ;\
ret
#elif defined(__aarch64__)
- mov x8, #__NR_execve
- /* x0, x1 and x2 already contain the right arguments. */
-my_execve_syscall:
+#define SYSCALL(NAME, NR) \
+.global NAME ;\
+NAME: ;\
+ mov x8, NR ;\
+ /* x0, x1 and x2 already contain the right arguments. */ \
+NAME ## _syscall: ;\
svc #0
#else
# error "Unsupported architecture"
#endif
+
+SYSCALL (my_execve, __NR_execve)
--
2.36.0
next prev parent reply other threads:[~2022-07-13 22:25 UTC|newest]
Thread overview: 72+ messages / expand[flat|nested] mbox.gz Atom feed top
2022-07-13 22:24 [PATCH v2 00/29] Step over thread clone and thread exit Pedro Alves
2022-07-13 22:24 ` [PATCH v2 01/29] displaced step: pass down target_waitstatus instead of gdb_signal Pedro Alves
2022-07-20 20:21 ` Simon Marchi
2022-07-13 22:24 ` [PATCH v2 02/29] linux-nat: introduce pending_status_str Pedro Alves
2022-07-20 20:38 ` Simon Marchi
2022-07-13 22:24 ` [PATCH v2 03/29] gdb/linux: Delete all other LWPs immediately on ptrace exec event Pedro Alves
2022-07-21 0:45 ` Simon Marchi
2022-07-13 22:24 ` [PATCH v2 04/29] Step over clone syscall w/ breakpoint, TARGET_WAITKIND_THREAD_CLONED Pedro Alves
2022-07-21 1:35 ` Simon Marchi
2022-10-17 18:54 ` Pedro Alves
2022-10-18 12:40 ` [PATCH] Don't explicitly set clone child ptrace options (was: Re: [PATCH v2 04/29] Step over clone syscall w/ breakpoint, TARGET_WAITKIND_THREAD_CLONED) Pedro Alves
2022-10-28 14:50 ` Simon Marchi
2022-12-12 20:13 ` [PATCH v2 04/29] Step over clone syscall w/ breakpoint, TARGET_WAITKIND_THREAD_CLONED Pedro Alves
2022-07-13 22:24 ` [PATCH v2 05/29] Support clone events in the remote protocol Pedro Alves
2022-07-21 2:25 ` Simon Marchi
2022-12-12 20:14 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 06/29] Avoid duplicate QThreadEvents packets Pedro Alves
2022-07-21 2:30 ` Simon Marchi
2022-12-12 20:14 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 07/29] Thread options & clone events (core + remote) Pedro Alves
2022-07-21 3:14 ` Simon Marchi
2022-10-27 19:55 ` [PATCH] enum_flags to_string (was: Re: [PATCH v2 07/29] Thread options & clone events (core + remote)) Pedro Alves
2022-10-28 10:26 ` [PATCH v2] " Pedro Alves
2022-10-28 11:08 ` [PATCH v3] " Pedro Alves
2022-10-28 15:59 ` Simon Marchi
2022-10-28 18:23 ` Pedro Alves
2022-10-31 12:47 ` Simon Marchi
2022-11-07 17:26 ` [PATCH v5] " Pedro Alves
2022-11-07 18:29 ` Simon Marchi
2022-11-08 14:56 ` Pedro Alves
2022-12-12 20:15 ` [PATCH v2 07/29] Thread options & clone events (core + remote) Pedro Alves
2022-07-13 22:24 ` [PATCH v2 08/29] Thread options & clone events (native Linux) Pedro Alves
2022-07-21 12:38 ` Simon Marchi
2022-12-12 20:16 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 09/29] Thread options & clone events (Linux GDBserver) Pedro Alves
2022-07-21 13:11 ` Simon Marchi
2022-12-12 20:16 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 10/29] gdbserver: Hide and don't detach pending clone children Pedro Alves
2022-07-13 22:24 ` [PATCH v2 11/29] Remove gdb/19675 kfails (displaced stepping + clone) Pedro Alves
2022-07-13 22:24 ` [PATCH v2 12/29] Add test for stepping over clone syscall Pedro Alves
2022-07-13 22:24 ` [PATCH v2 13/29] all-stop/synchronous RSP support thread-exit events Pedro Alves
2022-07-13 22:24 ` [PATCH v2 14/29] gdbserver/linux-low.cc: Ignore event_ptid if TARGET_WAITKIND_IGNORE Pedro Alves
2022-07-13 22:24 ` [PATCH v2 15/29] Introduce GDB_TO_EXIT thread option, fix step-over-thread-exit Pedro Alves
2022-07-13 22:24 ` [PATCH v2 16/29] Implement GDB_TO_EXIT support for Linux GDBserver Pedro Alves
2022-07-13 22:24 ` [PATCH v2 17/29] Implement GDB_TO_EXIT support for native Linux Pedro Alves
2022-07-21 15:26 ` Simon Marchi
2022-12-12 20:17 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 18/29] gdb: clear step over information on thread exit (PR gdb/27338) Pedro Alves
2022-07-21 18:12 ` Simon Marchi
2022-12-12 20:18 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 19/29] stop_all_threads: (re-)enable async before waiting for stops Pedro Alves
2022-07-21 18:21 ` Simon Marchi
2022-12-12 20:18 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 20/29] gdbserver: Queue no-resumed event after thread exit Pedro Alves
2022-07-13 22:24 ` [PATCH v2 21/29] Don't resume new threads if scheduler-locking is in effect Pedro Alves
2022-07-14 5:28 ` Eli Zaretskii
2022-07-21 18:49 ` Simon Marchi
2022-12-12 20:19 ` Pedro Alves
2022-07-13 22:24 ` [PATCH v2 22/29] Report thread exit event for leader if reporting thread exit events Pedro Alves
2022-07-13 22:24 ` [PATCH v2 23/29] Ignore failure to read PC when resuming Pedro Alves
2022-07-13 22:24 ` Pedro Alves [this message]
2022-07-13 22:24 ` [PATCH v2 25/29] Testcases for stepping over thread exit syscall (PR gdb/27338) Pedro Alves
2022-07-13 22:24 ` [PATCH v2 26/29] Document remote clone events, and QThreadOptions packet Pedro Alves
2022-07-14 5:27 ` Eli Zaretskii
2022-07-13 22:24 ` [PATCH v2 27/29] inferior::clear_thread_list always silent Pedro Alves
2022-07-13 22:24 ` [PATCH v2 28/29] Centralize "[Thread ...exited]" notifications Pedro Alves
2022-07-13 22:24 ` [PATCH v2 29/29] Cancel execution command on thread exit, when stepping, nexting, etc Pedro Alves
2022-07-21 19:28 ` [PATCH v2 00/29] Step over thread clone and thread exit Simon Marchi
2022-10-03 13:46 ` Tom de Vries
2022-10-03 18:37 ` Tom de Vries
2022-12-12 20:20 ` Pedro Alves
2022-12-12 20:19 ` Pedro Alves
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20220713222433.374898-25-pedro@palves.net \
--to=pedro@palves.net \
--cc=gdb-patches@sourceware.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for read-only IMAP folder(s) and NNTP newsgroup(s).