From nobody Mon Feb 9 12:14:50 2026 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 1E2DCEB64DD for ; Wed, 12 Jul 2023 09:22:46 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231308AbjGLJWo (ORCPT ); Wed, 12 Jul 2023 05:22:44 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:38316 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S232190AbjGLJW2 (ORCPT ); Wed, 12 Jul 2023 05:22:28 -0400 Received: from bg4.exmail.qq.com (bg4.exmail.qq.com [43.154.54.12]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 21D43E5F; Wed, 12 Jul 2023 02:21:44 -0700 (PDT) X-QQ-mid: bizesmtp66t1689153656te3bxl5e Received: from linux-lab-host.localdomain ( [116.30.126.249]) by bizesmtp.qq.com (ESMTP) with id ; Wed, 12 Jul 2023 17:20:55 +0800 (CST) X-QQ-SSF: 01200000000000D0W000000A0000000 X-QQ-FEAT: f0e3nd0UjDMWyqMb2OvZ3nICQJEiN23es6rzV5wC4cahNSci93zk5avdkN9io q6BYdGJoZRmuMT5rlrQMLsTfYs1JDiRGxLhXm10fh6zUHduZJaJzzdEtPFbZO2sRNnVY/Uf 8Skorwq/S+JEevTOwGrg/t8gy1kUoX5xgEbi/iZ+uiG1SnDVRlw5OroSC880NrikfhbX63H w4zF2E/cFDLmhtmGtHgNB6jMVLFmBbcIZL/11fBfv0u3A3oWwXw+n6Xv6ZP87Z0k4MjQdUV qHnx5Qzfeg5RQdshjphvVgMsmNaMXJ6oh04J6bswf9QBTwjTrkRx8j2hcVC8HUQt2ZNFPHr UkhFXblDdj8PllkZNal2brCfOMD9kbgKoDfE18K77we3a08FPPu8rZmNG75hdxty3rf8GWg X-QQ-GoodBg: 0 X-BIZMAIL-ID: 2211699565622657830 From: Zhangjin Wu To: w@1wt.eu Cc: falcon@tinylab.org, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, thomas@t-8ch.de Subject: [PATCH v3 05/11] tools/nolibc: i386: shrink _start with _start_c Date: Wed, 12 Jul 2023 17:20:55 +0800 Message-Id: <29e5222e81983e46c0dd8c043db66820ed80638b.1689150149.git.falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrgz:qybglogicsvrgz5a-1 Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Type: text/plain; charset="utf-8" move most of the _start operations to _start_c(). Signed-off-by: Zhangjin Wu --- tools/include/nolibc/arch-i386.h | 33 ++++++++------------------------ 1 file changed, 8 insertions(+), 25 deletions(-) diff --git a/tools/include/nolibc/arch-i386.h b/tools/include/nolibc/arch-i= 386.h index 1d4b683bc2cd..f0d0f5c364b8 100644 --- a/tools/include/nolibc/arch-i386.h +++ b/tools/include/nolibc/arch-i386.h @@ -8,6 +8,7 @@ #define _NOLIBC_ARCH_I386_H =20 #include "compiler.h" +#include "crt.h" =20 /* Syscalls for i386 : * - mostly similar to x86_64 @@ -154,9 +155,6 @@ _eax; \ }) =20 -char **environ __attribute__((weak)); -const unsigned long *_auxv __attribute__((weak)); - /* startup code */ /* * i386 System V ABI mandates: @@ -168,29 +166,14 @@ void __attribute__((weak,noreturn,optimize("omit-fram= e-pointer"))) __no_stack_pr { __asm__ volatile ( #ifdef _NOLIBC_STACKPROTECTOR - "call __stack_chk_init\n" /* initialize stack protector = */ + "call __stack_chk_init\n" /* initialize stack protector = */ #endif - "pop %eax\n" /* argc (first arg, %eax) = */ - "mov %esp, %ebx\n" /* argv[] (second arg, %ebx) = */ - "lea 4(%ebx,%eax,4),%ecx\n" /* then a NULL then envp (third arg, %ecx) = */ - "mov %ecx, environ\n" /* save environ = */ - "xor %ebp, %ebp\n" /* zero the stack frame = */ - "mov %ecx, %edx\n" /* search for auxv (follows NULL after last = env) */ - "0:\n" - "add $4, %edx\n" /* search for auxv using edx, it follows the= */ - "cmp -4(%edx), %ebp\n" /* ... NULL after last env (ebp is zero here= ) */ - "jnz 0b\n" - "mov %edx, _auxv\n" /* save it into _auxv = */ - "and $-16, %esp\n" /* x86 ABI : esp must be 16-byte aligned bef= ore */ - "sub $4, %esp\n" /* the call instruction (args are aligned) = */ - "push %ecx\n" /* push all registers on the stack so that w= e */ - "push %ebx\n" /* support both regparm and plain stack mode= s */ - "push %eax\n" - "call main\n" /* main() returns the status code in %eax = */ - "mov %eax, %ebx\n" /* retrieve exit code (32-bit int) = */ - "movl $1, %eax\n" /* NR_exit =3D=3D 1 = */ - "int $0x80\n" /* exit now = */ - "hlt\n" /* ensure it does not = */ + "xor %ebp, %ebp\n" /* zero the stack frame = */ + "mov %esp, %eax\n" /* save stack pointer to %eax, as arg1 of _sta= rt_c */ + "and $-16, %esp\n" /* last pushed argument must be 16-byte aligne= d */ + "push %eax\n" /* push arg1 on stack to support plain stack m= odes too */ + "call _start_c\n" /* transfer to c runtime = */ + "hlt\n" /* ensure it does not return = */ ); __builtin_unreachable(); } --=20 2.25.1