From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp-out2.suse.de (smtp-out2.suse.de [IPv6:2001:67c:2178:6::1d]) by sourceware.org (Postfix) with ESMTPS id 137B73857C5A for ; Thu, 23 Feb 2023 12:54:29 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 137B73857C5A Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=suse.de Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=suse.de Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out2.suse.de (Postfix) with ESMTPS id 04E875D913; Thu, 23 Feb 2023 12:54:28 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1677156868; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type; bh=LKU0SkWfiKJGSdHDv14IfJTONGQx7EXisV2rUn/kyZo=; b=y3PvrGxjawpR7sjBH+VEmUAmsMv05q2vUlkIJtNpYJ5VZl8MAT9nuiHexNUTED6dHp1qQT 06GjS+eYhjgEFTr8vqjThzNOE48kZDwXDkr4Ko/KWi8YvZRtK8j44zJ9Rt8XaMf4xdn5Ki GAv+KUyq05Md91n0mXHgmyBgMcJ4XfM= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1677156868; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version:content-type:content-type; bh=LKU0SkWfiKJGSdHDv14IfJTONGQx7EXisV2rUn/kyZo=; b=5+/xBg5+VT140U/F+gSNV3J/F6CML+p+iybwbXS95x1Y1De4qYuDjKo4QqZZCSUGIzanAm qPvGTdMxlorobYDA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id DA402139B5; Thu, 23 Feb 2023 12:54:27 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id zBMiNANi92OHYQAAMHmgww (envelope-from ); Thu, 23 Feb 2023 12:54:27 +0000 Date: Thu, 23 Feb 2023 13:54:27 +0100 (CET) From: Richard Biener To: gcc-patches@gcc.gnu.org cc: Jakub Jelinek Subject: [PATCH] Avoid default-initializing auto_vec storage MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Message-Id: <20230223125427.DA402139B5@imap2.suse-dmz.suse.de> X-Spam-Status: No, score=-11.7 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,GIT_PATCH_0,SPF_HELO_NONE,SPF_PASS,TXREP autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on server2.sourceware.org List-Id: The following avoids default-initializing auto_vec storage for non-POD T since that's not what the allocated storage fallback will do and it's also not expected for existing cases like auto_vec, 64> elts; which exist to optimize the allocation. Bootstrapped and tested on x86_64-unknown-linux-gnu. It saves around 1kB of text size for cc1. OK for trunk? Thanks, Richard. * vec.h (auto_vec): Turn m_data storage into uninitialized unsigned char. --- gcc/vec.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/gcc/vec.h b/gcc/vec.h index a536b68732d..cee96254a31 100644 --- a/gcc/vec.h +++ b/gcc/vec.h @@ -1584,7 +1584,7 @@ public: private: vec m_auto; - T m_data[MAX (N - 1, 1)]; + alignas(T) unsigned char m_data[sizeof (T) * MAX (N - 1, 1)]; }; /* auto_vec is a sub class of vec whose storage is released when it is -- 2.35.3