From patchwork Wed Jun 28 19:04:12 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Zhangjin Wu X-Patchwork-Id: 697581 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 2C466EB64D7 for ; Wed, 28 Jun 2023 19:06:36 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231745AbjF1TGE (ORCPT ); Wed, 28 Jun 2023 15:06:04 -0400 Received: from bg4.exmail.qq.com ([43.155.65.254]:51133 "EHLO bg4.exmail.qq.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S231614AbjF1TFt (ORCPT ); Wed, 28 Jun 2023 15:05:49 -0400 X-QQ-mid: bizesmtp81t1687979140twy3oz5l Received: from linux-lab-host.localdomain ( [116.30.129.193]) by bizesmtp.qq.com (ESMTP) with id ; Thu, 29 Jun 2023 03:05:38 +0800 (CST) X-QQ-SSF: 01200000000000D0W000000A0000000 X-QQ-FEAT: QityeSR92A0ivM8Oe5i1P8PgBPy/0WKQrP/bau1yZUyBIMxZ5v5/nq5XSmhEo YaCWksBQ8b9i4Oiy0QKM2HQhJUQxhtH6I0PmpEJH68qNQ2/UUaq1iQcgOX+RFZ7zBKo7g2i 8fglSXNIJqe1lroojRhULNzSXIilkUv2ECoShgSwtnYMb8eO2nqScTXKGmhyfnDiF9jnlDx EoLxIAA7wqjl9DMajcD+s3Rmv+4Agv5M+PyV3e1dbGHOM6kMSvcfKligJTkTbcrf1Q4vzhI RHzPS9ot3goSP+6inAJpovN0PDWV+1j5DgDpGx20+T9RNlw8H3wOshH2sdaJnutu92MSj60 JpBup9/hmlDjscis/Y5N6ZqzwwRTzi7UX5BHcqVDB3wJsLZSWcsAmohQngzAg== X-QQ-GoodBg: 0 X-BIZMAIL-ID: 17283120326487235982 From: Zhangjin Wu To: thomas@t-8ch.de, w@1wt.eu Cc: falcon@tinylab.org, arnd@arndb.de, linux-kernel@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-riscv@lists.infradead.org Subject: [PATCH v1 10/11] tools/nolibc: riscv: shrink _start with _start_c Date: Thu, 29 Jun 2023 03:04:12 +0800 Message-Id: <4a6e7245c3aa07eb20fd6c6aa43bc663e480e0c5.1687976753.git.falcon@tinylab.org> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 X-QQ-SENDSIZE: 520 Feedback-ID: bizesmtp:tinylab.org:qybglogicsvrsz:qybglogicsvrsz3a-3 Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org Let's move most of the _start operations to _start_c(). Signed-off-by: Zhangjin Wu --- tools/include/nolibc/arch-riscv.h | 42 ++++--------------------------- 1 file changed, 5 insertions(+), 37 deletions(-) diff --git a/tools/include/nolibc/arch-riscv.h b/tools/include/nolibc/arch-riscv.h index 7f4abcc15206..ec0f9c597d0b 100644 --- a/tools/include/nolibc/arch-riscv.h +++ b/tools/include/nolibc/arch-riscv.h @@ -9,18 +9,6 @@ #include "compiler.h" -#if __riscv_xlen == 64 -#define PTRLOG "3" -#define SZREG "8" -#define REG_L "ld" -#define REG_S "sd" -#elif __riscv_xlen == 32 -#define PTRLOG "2" -#define SZREG "4" -#define REG_L "lw" -#define REG_S "sw" -#endif - /* Syscalls for RISCV : * - stack is 16-byte aligned * - syscall number is passed in a7 @@ -153,40 +141,20 @@ _arg1; \ }) -char **environ __attribute__((weak)); -const unsigned long *_auxv __attribute__((weak)); - /* startup code */ void __attribute__((weak,noreturn,optimize("omit-frame-pointer"))) __no_stack_protector _start(void) { __asm__ volatile ( ".option push\n" ".option norelax\n" - "lla gp, __global_pointer$\n" + "lla gp, __global_pointer$\n" ".option pop\n" #ifdef _NOLIBC_STACKPROTECTOR - "call __stack_chk_init\n" /* initialize stack protector */ + "call __stack_chk_init\n" /* initialize stack protector */ #endif - REG_L" a0, 0(sp)\n" /* argc (a0) was in the stack */ - "add a1, sp, "SZREG"\n" /* argv (a1) = sp */ - "slli a2, a0, "PTRLOG"\n" /* envp (a2) = SZREG*argc ... */ - "add a2, a2, "SZREG"\n" /* + SZREG (skip null) */ - "add a2,a2,a1\n" /* + argv */ - - "add a3, a2, zero\n" /* iterate a3 over envp to find auxv (after NULL) */ - "0:\n" /* do { */ - REG_L" a4, 0(a3)\n" /* a4 = *a3; */ - "add a3, a3, "SZREG"\n" /* a3 += sizeof(void*); */ - "bne a4, zero, 0b\n" /* } while (a4); */ - "lui a4, %hi(_auxv)\n" /* a4 = &_auxv (high bits) */ - REG_S" a3, %lo(_auxv)(a4)\n" /* store a3 into _auxv */ - - "lui a3, %hi(environ)\n" /* a3 = &environ (high bits) */ - REG_S" a2,%lo(environ)(a3)\n"/* store envp(a2) into environ */ - "andi sp,a1,-16\n" /* sp must be 16-byte aligned */ - "call main\n" /* main() returns the status code, we'll exit with it. */ - "li a7, 93\n" /* NR_exit == 93 */ - "ecall\n" + "mv a0, sp\n" /* save stack pointer to a0, as arg1 of _start_c*/ + "andi sp, a0, -16\n" /* sp must be 16-byte aligned */ + "call _start_c\n" /* transfer to c runtime */ ); __builtin_unreachable(); }