From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pj1-x1029.google.com (mail-pj1-x1029.google.com [IPv6:2607:f8b0:4864:20::1029]) by sourceware.org (Postfix) with ESMTPS id DADFC3858D33 for ; Wed, 1 Feb 2023 20:27:01 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org DADFC3858D33 Authentication-Results: sourceware.org; dmarc=pass (p=none dis=none) header.from=linaro.org Authentication-Results: sourceware.org; spf=pass smtp.mailfrom=linaro.org Received: by mail-pj1-x1029.google.com with SMTP id 88so18431161pjo.3 for ; Wed, 01 Feb 2023 12:27:01 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linaro.org; s=google; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :from:to:cc:subject:date:message-id:reply-to; bh=5AiRNAhM6eZL10nbAlcZe7nlXi2OS0fWcYitRWDSs/k=; b=WizuvgVvRxnyDCbYgnKgCg547Mwxo1kjD6dKN5LttJWPDKQ0BeIa6cp8l2m57OR6VW jNjHudZJ11agOQyAkJGjD3Qy3wAVv4/ONWcM8gI/vNzrqvGWDWGnCkoi7PI9imIe9wWL ztSfe0rSJBxlocLgv/VhRGBrmt4e1YLmjZ3rPrDyhW89JGdymTG3p8Fyafbxy3AYUjjf nt3xiAu9BO3JqFV/aYISGycLR33pcY75unymzm2iLoWKMGlIdc/h7HPO3ozUjNjmEkS+ RF8ZaIQ3cqKST2K1VbuW9w47+ZW9kMzn0rlpEvbDU4pYxJifHEoJoNwRsIymIcKWAN2F mDmg== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:from:references:cc:to :content-language:subject:user-agent:mime-version:date:message-id :x-gm-message-state:from:to:cc:subject:date:message-id:reply-to; bh=5AiRNAhM6eZL10nbAlcZe7nlXi2OS0fWcYitRWDSs/k=; b=y0S8G+Ltdc0CgD9yNdjyWsGW57ZRsrZ9d+kVP/DKYQSd0qNKCIRfYeRBRaffM2665a b09DjFn7VTeZOUw4tPyIC303s/P+po9m70rB/2VdaeOFtaMK4XdmQUk5KaoN2Gl78kn8 CNw2Moy4Nu+zOTKrEE7IXM+eTJUHXxDcyMcl+asq6iGe7PvpDEOATZJd9GfCoRdVdS9u DzlqRMgMktCCJ+v1daM9qSsf/PqkIm8+ntTDDTYM8wU/qjaFxHDNxdGaamf7Gd9lBn4b QAHEUBMcTSoPHAIuFtEufDeO/8qJgauHZxWRLxdJ56WkFTw8GdJibJ/SkR6YRYp8d5HL m65g== X-Gm-Message-State: AO0yUKWU6i3NL3EWavgtAeqCqHg91jIY5jSgo/PDR9MQgU3Sk5A7CS8Q /+dFGVr/v3XlFc3m9HM7JKewZA== X-Google-Smtp-Source: AK7set+jibgPvH0hU+DPoyWe3veHDEq0CMzLkvLUgQTcBcXDDLMpPAFYXkTzkpy+EqGdwMCMQu64Sw== X-Received: by 2002:a17:903:41c9:b0:196:2e10:ba5c with SMTP id u9-20020a17090341c900b001962e10ba5cmr4039882ple.49.1675283221020; Wed, 01 Feb 2023 12:27:01 -0800 (PST) Received: from [192.168.50.50] (rrcs-173-197-98-118.west.biz.rr.com. [173.197.98.118]) by smtp.gmail.com with ESMTPSA id je3-20020a170903264300b00196519d8647sm3875007plb.4.2023.02.01.12.26.59 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Wed, 01 Feb 2023 12:27:00 -0800 (PST) Message-ID: <9c954274-c719-79f4-a9bb-dadaef63d383@linaro.org> Date: Wed, 1 Feb 2023 10:26:57 -1000 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.2 Subject: Re: [PATCH v11 10/29] string: Improve generic stpcpy Content-Language: en-US To: Noah Goldstein , Adhemerval Zanella Cc: libc-alpha@sourceware.org, Jeff Law , Xi Ruoyao References: <20230201170406.303978-1-adhemerval.zanella@linaro.org> <20230201170406.303978-11-adhemerval.zanella@linaro.org> From: Richard Henderson In-Reply-To: Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit X-Spam-Status: No, score=-5.7 required=5.0 tests=BAYES_00,DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,NICE_REPLY_A,RCVD_IN_DNSWL_NONE,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: On 2/1/23 09:47, Noah Goldstein wrote: >> +static __always_inline char * >> +stpcpy_unaligned_loop (op_t *restrict dst, const op_t *restrict src, >> + uintptr_t ofs) >> +{ > > Is the perf cost of unaligned stores greater than merging? Generically, yes. Some hosts have no hw unaligned stores at all without even fallback to trap and emulate, and compiler-generated unaligned stores devolve to byte-by-byte. r~