From patchwork Wed Jun 19 11:26:11 2024 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Julian Zhu X-Patchwork-Id: 92425 Return-Path: X-Original-To: patchwork@sourceware.org Delivered-To: patchwork@sourceware.org Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id D5EBB3885C19 for ; Wed, 19 Jun 2024 11:26:40 +0000 (GMT) X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from nisdydeair.tail4cdaa.ts.net (unknown [IPv6:2605:52c0:2:e9a:307b:dbff:fe9d:66cf]) by sourceware.org (Postfix) with ESMTP id CAED0388450F for ; Wed, 19 Jun 2024 11:26:15 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org CAED0388450F Authentication-Results: sourceware.org; dmarc=fail (p=none dis=none) header.from=gmail.com Authentication-Results: sourceware.org; spf=none smtp.mailfrom=nisdydeair.tail4cdaa.ts.net ARC-Filter: OpenARC Filter v1.0.0 sourceware.org CAED0388450F Authentication-Results: server2.sourceware.org; arc=none smtp.remote-ip=2605:52c0:2:e9a:307b:dbff:fe9d:66cf ARC-Seal: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1718796377; cv=none; b=t7wD0s/390dSurTSXg3pL+mNVBXgRF8wQ6okbM9Vl1ZLenK8H3vLiiyKZyXGryfVG1gF6Hi3nLMCeF7NErAzRz71mdgc7cD9eRxLl4gJ3oalNj4OHmgVDxv2w0krKQ+T8pAnhXSa6HnJKwMz5P/9Z0e3Y0i3K72HCNL7QDAbQwI= ARC-Message-Signature: i=1; a=rsa-sha256; d=sourceware.org; s=key; t=1718796377; c=relaxed/simple; bh=1Uk9dG/rEfcjuzkME3i+lsewI0reN5X2Jy70bI82wUs=; h=From:To:Subject:Date:Message-ID:MIME-Version; b=fOoPHlkY4nuSQCP622kBb8KTke21aCsr292JMyppLyGP+IBuC4ExVFz+WEgdSXgtOdr56YfTIUiq5Ibls+ZcewG+rDC7dxHKRbN6LSfUqPxc0YGZX8Ya6MZfDrse7kAckz7MoGiLB+6AKg41oxHOSfYDyXNUeZdtUfGNWI9u4Sc= ARC-Authentication-Results: i=1; server2.sourceware.org Received: by nisdydeair.tail4cdaa.ts.net (Postfix, from userid 501) id 5D354274611E; Wed, 19 Jun 2024 19:26:13 +0800 (CST) From: Julian Zhu To: libc-alpha@sourceware.org Cc: Julian Zhu Subject: [PATCH v2] RISC-V: Use builtins for ffs and ffsll while supported extension available Date: Wed, 19 Jun 2024 19:26:11 +0800 Message-ID: <20240619112611.2555-1-jz531210@gmail.com> X-Mailer: git-send-email 2.45.2 MIME-Version: 1.0 X-Spam-Status: No, score=-8.3 required=5.0 tests=BAYES_00, DKIM_ADSP_CUSTOM_MED, FORGED_GMAIL_RCVD, FREEMAIL_FORGED_FROMDOMAIN, FREEMAIL_FROM, GIT_PATCH_0, HEADER_FROM_DIFFERENT_DOMAINS, KAM_DMARC_NONE, KAM_DMARC_STATUS, KAM_LAZY_DOMAIN_SECURITY, KHOP_HELO_FCRDNS, NML_ADSP_CUSTOM_MED, NO_DNS_FOR_FROM, SPF_HELO_NONE, SPF_NONE, SPOOFED_FREEMAIL, SPOOF_GMAIL_MID, T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org X-BeenThere: libc-alpha@sourceware.org X-Mailman-Version: 2.1.30 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Errors-To: libc-alpha-bounces+patchwork=sourceware.org@sourceware.org Hardware `ctz`/`ctzw` instructions are available in the RISC-V Zbb extension, and the `ctz` instruction `th.ff1` is available in the RISC-V XTheadBb extension. We can get more simplified code compared to the generic implement of `ffs`/`ffsll`. Signed-off-by: Julian Zhu --- sysdeps/riscv/math-use-builtins-ffs.h | 7 +++++++ 1 file changed, 7 insertions(+) create mode 100644 sysdeps/riscv/math-use-builtins-ffs.h diff --git a/sysdeps/riscv/math-use-builtins-ffs.h b/sysdeps/riscv/math-use-builtins-ffs.h new file mode 100644 index 0000000000..a803be5cb3 --- /dev/null +++ b/sysdeps/riscv/math-use-builtins-ffs.h @@ -0,0 +1,7 @@ +#if defined __riscv_zbb +#define USE_FFS_BUILTIN 1 +#define USE_FFSLL_BUILTIN 1 +#elif __riscv_xtheadbb +#define USE_FFS_BUILTIN 0 +#define USE_FFSLL_BUILTIN 1 +#endif