From patchwork Tue Jul 18 14:15:38 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809308 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=MQJSpWmk; dkim-atps=neutral Received: from server2.sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R51G20M3Lz20FY for ; Wed, 19 Jul 2023 00:16:09 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CDB9D3855591 for ; Tue, 18 Jul 2023 14:16:07 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CDB9D3855591 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1689689767; bh=r3V7J/+051rcRxu3Q9N9c+X0qH2ZGC50l+QPtSbnWTs=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=MQJSpWmkMbmK/P6YtXCskwJTg9zhqnh5/wbGZqbcgwzomSCTPezmRaVhjc14UEHy2 xvqO6HdUgjzGBqKDHaEzE6R78KdgGfSa6k6Yz86VHAO8dWMwmr9v0PUy+nd5O1T+sc Wsc0n7RazKWGVnPb71G/EjU6xk0rjzeOIiAAPENc= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oa1-x29.google.com (mail-oa1-x29.google.com [IPv6:2001:4860:4864:20::29]) by sourceware.org (Postfix) with ESMTPS id D4024385773C for ; Tue, 18 Jul 2023 14:15:52 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org D4024385773C Received: by mail-oa1-x29.google.com with SMTP id 586e51a60fabf-1b00b0ab0daso4784955fac.0 for ; Tue, 18 Jul 2023 07:15:52 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689689751; x=1690294551; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=r3V7J/+051rcRxu3Q9N9c+X0qH2ZGC50l+QPtSbnWTs=; b=ajn/ULcLw1Z4OPfm1FXhKG+74olvAc+ON+cMB/9q1prE5cdRjQCNfr7VWNTotCzUBq g3ps1+yJDtsUdHttgfhRD12IczX7g0WgLGMCuC6+q29hkKdrjeYJ754GN2NKGQVdkupz uZ3pnvh8qcLQmjA1Z+qTuOzkDELauLRuRe55cbcFa5EHjbsCigfW/uorP/73jGYMgyjd 5/qmb1SQBgspkicNQT3YvmutDkxQHGag0nenncNfiXtSGbgh+Jzqm5WNk/4QDxRWTlq4 bOUGnM8VDTrGuA/RMACrB5yvUZs37FWi0YylmC+i2XsI4S/ZMaY2CeTPwQq/3uyCc8Vm Dybw== X-Gm-Message-State: ABy/qLaHi0bcG7yFiFIYCWEdLBlcpdeI6m0YaG2sgwPmPU7j7Rf+Et02 CF8wzcbaOEZLnrUjUkjB0+GpAyLONuqh/Nn9m6r0Nw== X-Google-Smtp-Source: APBJJlEMpohARyB/l89DBd9U/bqKxmzL9oKq70Q7v9iAlhCm4Gh/hX8AMDQgh0T1vxExY8QQ5TF8AA== X-Received: by 2002:a05:6870:ea82:b0:1b7:63e2:2944 with SMTP id s2-20020a056870ea8200b001b763e22944mr18788121oap.26.1689689751441; Tue, 18 Jul 2023 07:15:51 -0700 (PDT) Received: from mandiga.. ([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.49 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:15:50 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 1/6] stdlib: Optimization qsort{_r} swap implementation Date: Tue, 18 Jul 2023 11:15:38 -0300 Message-Id: <20230718141543.3925254-2-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.1 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" The optimization takes in consideration both the most common elements are either 32 or 64 bit in size and inputs are aligned to the word boundary. This is similar to what msort does. For large buffer the swap operation uses memcpy/mempcpy with a small fixed size buffer (so compiler might inline the operations). Checked on x86_64-linux-gnu. --- stdlib/qsort.c | 116 +++++++++++++++++++++++++++++++++++++++++-------- 1 file changed, 98 insertions(+), 18 deletions(-) diff --git a/stdlib/qsort.c b/stdlib/qsort.c index 728a0ed370..5bcc287c79 100644 --- a/stdlib/qsort.c +++ b/stdlib/qsort.c @@ -23,20 +23,92 @@ #include #include #include +#include -/* Byte-wise swap two items of size SIZE. */ -#define SWAP(a, b, size) \ - do \ - { \ - size_t __size = (size); \ - char *__a = (a), *__b = (b); \ - do \ - { \ - char __tmp = *__a; \ - *__a++ = *__b; \ - *__b++ = __tmp; \ - } while (--__size > 0); \ - } while (0) +/* Swap SIZE bytes between addresses A and B. These helpers are provided + along the generic one as an optimization. */ + +enum swap_type_t + { + SWAP_WORDS_64, + SWAP_WORDS_32, + SWAP_BYTES + }; + +/* If this function returns true, elements can be safely copied using word + loads and stores. Otherwise, it might not be safe. BASE (as an integer) + must be a multiple of the word alignment. SIZE must be a multiple of + WORDSIZE. Since WORDSIZE must be a multiple of the word alignment, and + WORDSIZE is a power of two on all supported platforms, this function for + speed merely checks that BASE and SIZE are both multiples of the word + size. */ +static inline bool +is_aligned (const void *base, size_t size, size_t wordsize) +{ + return (((uintptr_t) base | size) & (wordsize - 1)) == 0; +} + +static inline void +swap_words_64 (void * restrict a, void * restrict b, size_t n) +{ + typedef uint64_t __attribute__ ((__may_alias__)) u64_alias_t; + do + { + n -= 8; + u64_alias_t t = *(u64_alias_t *)(a + n); + *(u64_alias_t *)(a + n) = *(u64_alias_t *)(b + n); + *(u64_alias_t *)(b + n) = t; + } while (n); +} + +static inline void +swap_words_32 (void * restrict a, void * restrict b, size_t n) +{ + typedef uint32_t __attribute__ ((__may_alias__)) u32_alias_t; + do + { + n -= 4; + u32_alias_t t = *(u32_alias_t *)(a + n); + *(u32_alias_t *)(a + n) = *(u32_alias_t *)(b + n); + *(u32_alias_t *)(b + n) = t; + } while (n); +} + +static inline void +swap_bytes (void * restrict a, void * restrict b, size_t n) +{ + /* Use multiple small memcpys with constant size to enable inlining + on most targets. */ + enum { SWAP_GENERIC_SIZE = 32 }; + unsigned char tmp[SWAP_GENERIC_SIZE]; + while (n > SWAP_GENERIC_SIZE) + { + memcpy (tmp, a, SWAP_GENERIC_SIZE); + a = __mempcpy (a, b, SWAP_GENERIC_SIZE); + b = __mempcpy (b, tmp, SWAP_GENERIC_SIZE); + n -= SWAP_GENERIC_SIZE; + } + while (n > 0) + { + unsigned char t = ((unsigned char *)a)[--n]; + ((unsigned char *)a)[n] = ((unsigned char *)b)[n]; + ((unsigned char *)b)[n] = t; + } +} + +/* Replace the indirect call with a serie of if statements. It should help + the branch predictor. */ +static void +do_swap (void * restrict a, void * restrict b, size_t size, + enum swap_type_t swap_func) +{ + if (swap_func == SWAP_WORDS_64) + swap_words_64 (a, b, size); + else if (swap_func == SWAP_WORDS_32) + swap_words_32 (a, b, size); + else + swap_bytes (a, b, size); +} /* Discontinue quicksort algorithm when partition gets below this size. This particular magic number was chosen to work best on a Sun 4/260. */ @@ -96,6 +168,14 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, /* Avoid lossage with unsigned arithmetic below. */ return; + enum swap_type_t swap_type; + if (is_aligned (pbase, size, 8)) + swap_type = SWAP_WORDS_64; + else if (is_aligned (pbase, size, 4)) + swap_type = SWAP_WORDS_32; + else + swap_type = SWAP_BYTES; + if (total_elems > MAX_THRESH) { char *lo = base_ptr; @@ -119,13 +199,13 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, char *mid = lo + size * ((hi - lo) / size >> 1); if ((*cmp) ((void *) mid, (void *) lo, arg) < 0) - SWAP (mid, lo, size); + do_swap (mid, lo, size, swap_type); if ((*cmp) ((void *) hi, (void *) mid, arg) < 0) - SWAP (mid, hi, size); + do_swap (mid, hi, size, swap_type); else goto jump_over; if ((*cmp) ((void *) mid, (void *) lo, arg) < 0) - SWAP (mid, lo, size); + do_swap (mid, lo, size, swap_type); jump_over:; left_ptr = lo + size; @@ -144,7 +224,7 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, if (left_ptr < right_ptr) { - SWAP (left_ptr, right_ptr, size); + do_swap (left_ptr, right_ptr, size, swap_type); if (mid == left_ptr) mid = right_ptr; else if (mid == right_ptr) @@ -216,7 +296,7 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, tmp_ptr = run_ptr; if (tmp_ptr != base_ptr) - SWAP (tmp_ptr, base_ptr, size); + do_swap (tmp_ptr, base_ptr, size, swap_type); /* Insertion sort, running from left-hand-side up to right-hand-side. */ From patchwork Tue Jul 18 14:15:39 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809311 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=VSSQYe1J; dkim-atps=neutral Received: from server2.sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R51Gt3yWKz20FX for ; Wed, 19 Jul 2023 00:16:54 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 7CE8338708B4 for ; Tue, 18 Jul 2023 14:16:52 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7CE8338708B4 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1689689812; bh=TiPfJScFvR41TuzaiY6ZiU5DHhsCYdFSGCrLrlYS/9U=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=VSSQYe1JQkS6aEZrRM1VYRQDoxnRtIfrO7Oq0LA04y9GzUMAuqy189IGDQ7jRpVL6 6s6cEJu/hmmtE1HYJkYFOiI4Rlj0AEk2Q1KAOaXWUjd9qLlSMBt7mRWDMkWzPACZuK 9TUclhDWBbjOy6LsC8Qcxi8sex0r836BKL8+jM+s= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oo1-xc2f.google.com (mail-oo1-xc2f.google.com [IPv6:2607:f8b0:4864:20::c2f]) by sourceware.org (Postfix) with ESMTPS id C071A385701D for ; Tue, 18 Jul 2023 14:15:54 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org C071A385701D Received: by mail-oo1-xc2f.google.com with SMTP id 006d021491bc7-56347da4a50so3847826eaf.2 for ; Tue, 18 Jul 2023 07:15:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689689753; x=1690294553; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=TiPfJScFvR41TuzaiY6ZiU5DHhsCYdFSGCrLrlYS/9U=; b=YWkZU/OmZbUcJ3bRIym+O/xiukCR8V6KYlkvG5tWL9LCcHpnp6YVh6YQpXdjgBccee nWeudNfO8Tbn0acNATLfGyp91WOdDJ77U0u8ExX+JuGIoE5TEznJYWeWbWHyXecQBj2l Go+apy8B68Lfd5X+OlOSSmz21ZQQ1tyLgrWTYQSZ6B1Z0SzeHDtyu8IZfoduQjs6CzM6 PG0HPYKyn6zzZu88LgEyDmqEoMXJXpoc0YRTbrhWvMuoXCoJt34XHXaab3JmlRj8zeNf /wXUo8CQ69xvSpkD99qCStpGi6dMjwyOK7/9Xqm6J8gKdsD50/ytq+do4iamGssEWMEa T+fw== X-Gm-Message-State: ABy/qLZk6Uqxh0AH6Iuec7Vn98vosvVTN5q0J+5f8sN8xZCwTbRiP/cZ OiMpUMgwyfnw7qE8yTL+wBxZjlaFPz9z+NGhRIEMWA== X-Google-Smtp-Source: APBJJlGEv3HtOhaMLYDUwajMtVCCjV8qeBO4jcfMfIrgirZDwIwS7/tnhY0XWEtp7tkmxT1nOk7Y5w== X-Received: by 2002:a4a:9207:0:b0:566:6b6a:e1f with SMTP id f7-20020a4a9207000000b005666b6a0e1fmr7263935ooh.7.1689689753415; Tue, 18 Jul 2023 07:15:53 -0700 (PDT) Received: from mandiga.. ([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.51 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:15:52 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 2/6] stdlib: Move insertion sort out qsort Date: Tue, 18 Jul 2023 11:15:39 -0300 Message-Id: <20230718141543.3925254-3-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.4 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" --- stdlib/qsort.c | 101 ++++++++++++++++++++++++++----------------------- 1 file changed, 54 insertions(+), 47 deletions(-) diff --git a/stdlib/qsort.c b/stdlib/qsort.c index 5bcc287c79..77630951df 100644 --- a/stdlib/qsort.c +++ b/stdlib/qsort.c @@ -156,6 +156,58 @@ typedef struct smaller partition. This *guarantees* no more than log (total_elems) stack size is needed (actually O(1) in this case)! */ +static inline void +insertion_sort_qsort_partitions (void *const pbase, size_t total_elems, + size_t size, enum swap_type_t swap_func, + __compar_d_fn_t cmp, void *arg) +{ + char *base_ptr = (char *) pbase; + char *const end_ptr = &base_ptr[size * (total_elems - 1)]; + char *tmp_ptr = base_ptr; +#define min(x, y) ((x) < (y) ? (x) : (y)) + const size_t max_thresh = MAX_THRESH * size; + char *thresh = min(end_ptr, base_ptr + max_thresh); + char *run_ptr; + + /* Find smallest element in first threshold and place it at the + array's beginning. This is the smallest array element, + and the operation speeds up insertion sort's inner loop. */ + + for (run_ptr = tmp_ptr + size; run_ptr <= thresh; run_ptr += size) + if (cmp (run_ptr, tmp_ptr, arg) < 0) + tmp_ptr = run_ptr; + + if (tmp_ptr != base_ptr) + do_swap (tmp_ptr, base_ptr, size, swap_func); + + /* Insertion sort, running from left-hand-side up to right-hand-side. */ + + run_ptr = base_ptr + size; + while ((run_ptr += size) <= end_ptr) + { + tmp_ptr = run_ptr - size; + while (cmp (run_ptr, tmp_ptr, arg) < 0) + tmp_ptr -= size; + + tmp_ptr += size; + if (tmp_ptr != run_ptr) + { + char *trav; + + trav = run_ptr + size; + while (--trav >= run_ptr) + { + char c = *trav; + char *hi, *lo; + + for (hi = lo = trav; (lo -= size) >= tmp_ptr; hi = lo) + *hi = *lo; + *hi = c; + } + } + } +} + void _quicksort (void *const pbase, size_t total_elems, size_t size, __compar_d_fn_t cmp, void *arg) @@ -278,51 +330,6 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, for partitions below MAX_THRESH size. BASE_PTR points to the beginning of the array to sort, and END_PTR points at the very last element in the array (*not* one beyond it!). */ - -#define min(x, y) ((x) < (y) ? (x) : (y)) - - { - char *const end_ptr = &base_ptr[size * (total_elems - 1)]; - char *tmp_ptr = base_ptr; - char *thresh = min(end_ptr, base_ptr + max_thresh); - char *run_ptr; - - /* Find smallest element in first threshold and place it at the - array's beginning. This is the smallest array element, - and the operation speeds up insertion sort's inner loop. */ - - for (run_ptr = tmp_ptr + size; run_ptr <= thresh; run_ptr += size) - if ((*cmp) ((void *) run_ptr, (void *) tmp_ptr, arg) < 0) - tmp_ptr = run_ptr; - - if (tmp_ptr != base_ptr) - do_swap (tmp_ptr, base_ptr, size, swap_type); - - /* Insertion sort, running from left-hand-side up to right-hand-side. */ - - run_ptr = base_ptr + size; - while ((run_ptr += size) <= end_ptr) - { - tmp_ptr = run_ptr - size; - while ((*cmp) ((void *) run_ptr, (void *) tmp_ptr, arg) < 0) - tmp_ptr -= size; - - tmp_ptr += size; - if (tmp_ptr != run_ptr) - { - char *trav; - - trav = run_ptr + size; - while (--trav >= run_ptr) - { - char c = *trav; - char *hi, *lo; - - for (hi = lo = trav; (lo -= size) >= tmp_ptr; hi = lo) - *hi = *lo; - *hi = c; - } - } - } - } + insertion_sort_qsort_partitions (pbase, total_elems, size, swap_type, cmp, + arg); } From patchwork Tue Jul 18 14:15:40 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809309 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=rGDEysHO; dkim-atps=neutral Received: from server2.sourceware.org (ip-8-43-85-97.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R51GC0Jdxz20FX for ; Wed, 19 Jul 2023 00:16:18 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id CCBA63856DCB for ; Tue, 18 Jul 2023 14:16:16 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org CCBA63856DCB DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1689689776; bh=q9e+eAPpgtb4YGtW9SuJM8RXGmVNTGNbIt+1l2o5IbI=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=rGDEysHOh1+lR6KlByT+gEL+kGJhn3+dNTJ3zM5Srmcgmx6XR4nxnH1MKOa2ofWID 4g9cxE0XvYv7Zt0Kyn5ASXuuzQBpPxhotqcG9eHsLJr7sxdYpztoXxCo0U/8vZNgJy wkzI88JbafnzOX1dQqnz3RGXJvBJceGEhks7xypc= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oi1-x233.google.com (mail-oi1-x233.google.com [IPv6:2607:f8b0:4864:20::233]) by sourceware.org (Postfix) with ESMTPS id D623B385AF8E for ; Tue, 18 Jul 2023 14:15:56 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org D623B385AF8E Received: by mail-oi1-x233.google.com with SMTP id 5614622812f47-3a41da34780so3514458b6e.0 for ; Tue, 18 Jul 2023 07:15:56 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689689755; x=1690294555; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=q9e+eAPpgtb4YGtW9SuJM8RXGmVNTGNbIt+1l2o5IbI=; b=IYhtIx/j7OYAhnZVC8Eczwc/BYDFmVdYsyDnc34TbcFpHhfY+zDy1P2aMoKYgBFEQX FBwBM2H7Fn9manFwrxsmUJRUBiSugWmuPJmqBL+bS56SS4gvgr4pWyc+rOjDkGMO9lFC vyA6Y8pT/IrbvKPKL3cnJ3wZQ3aX77tZl0gSVvP5QurudzkPFoRtXPo0ZF6wixVXKury qSFAluzLA4VU6UVD0yJ6+I3ijHIIX0AmAvGG2bI3yaHzjQSh8FjXvSff/55h/eO5hGpN 0Pv5pmR6NtN/BJ7V+V89G3LEu5QZKoJRhkL15wLDe2WpwFm86hhs4x5DdyoYD/xnbcfO DOhQ== X-Gm-Message-State: ABy/qLaLN3Gzr9C/oPTK3fON+Vk0cGsL92GJVPypodaRR8CSLJt7W8QS /3IqNDfm8oyBsyw0oWoG13LVnLvUZ5YP/2A9kyK4OQ== X-Google-Smtp-Source: APBJJlGEJ/ZS3TrBRJN944xvGhGJlT30nOlGh0VxC35JlP6HlqyRMX2DeuMdlYe0sxZNiBjKgF0Jkw== X-Received: by 2002:a05:6808:1914:b0:3a1:bced:9e83 with SMTP id bf20-20020a056808191400b003a1bced9e83mr10173312oib.5.1689689755572; Tue, 18 Jul 2023 07:15:55 -0700 (PDT) Received: from mandiga.. ([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:15:54 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 3/6] stdlib: qsort: Move some macros to inline function Date: Tue, 18 Jul 2023 11:15:40 -0300 Message-Id: <20230718141543.3925254-4-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.5 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" --- stdlib/qsort.c | 35 +++++++++++++++++++++++------------ 1 file changed, 23 insertions(+), 12 deletions(-) diff --git a/stdlib/qsort.c b/stdlib/qsort.c index 77630951df..640896a598 100644 --- a/stdlib/qsort.c +++ b/stdlib/qsort.c @@ -121,15 +121,28 @@ typedef struct char *hi; } stack_node; -/* The next 4 #defines implement a very fast in-line stack abstraction. */ /* The stack needs log (total_elements) entries (we could even subtract log(MAX_THRESH)). Since total_elements has type size_t, we get as upper bound for log (total_elements): bits per byte (CHAR_BIT) * sizeof(size_t). */ -#define STACK_SIZE (CHAR_BIT * sizeof (size_t)) -#define PUSH(low, high) ((void) ((top->lo = (low)), (top->hi = (high)), ++top)) -#define POP(low, high) ((void) (--top, (low = top->lo), (high = top->hi))) -#define STACK_NOT_EMPTY (stack < top) +enum { STACK_SIZE = CHAR_BIT * sizeof (size_t) }; + +static inline stack_node * +push (stack_node *top, char *lo, char *hi) +{ + top->lo = lo; + top->hi = hi; + return ++top; +} + +static inline stack_node * +pop (stack_node *top, char **lo, char **hi) +{ + --top; + *lo = top->lo; + *hi = top->hi; + return top; +} /* Order size using quicksort. This implementation incorporates @@ -233,11 +246,9 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, char *lo = base_ptr; char *hi = &lo[size * (total_elems - 1)]; stack_node stack[STACK_SIZE]; - stack_node *top = stack; - - PUSH (NULL, NULL); + stack_node *top = stack + 1; - while (STACK_NOT_EMPTY) + while (stack < top) { char *left_ptr; char *right_ptr; @@ -302,7 +313,7 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, { if ((size_t) (hi - left_ptr) <= max_thresh) /* Ignore both small partitions. */ - POP (lo, hi); + top = pop (top, &lo, &hi); else /* Ignore small left partition. */ lo = left_ptr; @@ -313,13 +324,13 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, else if ((right_ptr - lo) > (hi - left_ptr)) { /* Push larger left partition indices. */ - PUSH (lo, right_ptr); + top = push (top, lo, right_ptr); lo = left_ptr; } else { /* Push larger right partition indices. */ - PUSH (left_ptr, hi); + top = push (top, left_ptr, hi); hi = right_ptr; } } From patchwork Tue Jul 18 14:15:41 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809314 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=8.43.85.97; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=LsZU1+RH; dkim-atps=neutral Received: from server2.sourceware.org (server2.sourceware.org [8.43.85.97]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R51Jm5W3Bz20FX for ; Wed, 19 Jul 2023 00:18:32 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id A0B7A386CE56 for ; Tue, 18 Jul 2023 14:18:30 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org A0B7A386CE56 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1689689910; bh=/Josf0pFHpkV09ffzOPMBqVmp/N5PZCtxGa+8JX9nX0=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=LsZU1+RH7elRKhmtktxckxyNbVYaHmvBenTMZ1RYYPut3SwWndM5ibxhNq09eJt5Q JjF0DAsxND1bVBTCeDSXy2sN4COruVVFaa+apg79hvX4/DaM+lrQr3wxOfHcIbFnEZ ZPN3s9CmuE6DYn8M0mFUy3/aI6r3m0ChUJepIc4k= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oa1-x35.google.com (mail-oa1-x35.google.com [IPv6:2001:4860:4864:20::35]) by sourceware.org (Postfix) with ESMTPS id EE41A385AFBF for ; Tue, 18 Jul 2023 14:15:58 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org EE41A385AFBF Received: by mail-oa1-x35.google.com with SMTP id 586e51a60fabf-1b3c503af99so3997125fac.0 for ; Tue, 18 Jul 2023 07:15:58 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689689757; x=1690294557; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=/Josf0pFHpkV09ffzOPMBqVmp/N5PZCtxGa+8JX9nX0=; b=ZQPiV2U2SpPK4rsQ0Atg7mhuZuTmlUsFTPFo4qVAYCApGKn+tqAA4/8qHhLlptfFMY VqNm0KkAE5iAtAm+kUyJB6L4+5gGHQgMb4Zj5EiIVzDeBfg9Il8iUveZ/QW9d9rXO3Oo TY5qfcu5YikyWRuIp8P66GJwyR8tPPkaIkB4KDl2EIZYfdyXBTCUs1P5G5JQBnIhKf00 IBxBY3HtaCad89dne/V8ZcbT8+TxItaB+mM3/k6HrxhVpKbgd93JDNb9njxls3LwuUCq 5OATIU4EAuppFcgxWCsDMmpVpRwLsM8OQpOYTvXf/6vYGnCVDy2O+nUmlZq54f+6M4su JaFg== X-Gm-Message-State: ABy/qLbAwDmEG86rV8/tQqo45IVQeL8ZGO+3Z8mIl13Ij+WAZRBJYYJp NXlmZyqvwzsqZboEFADtjBjXMThZO2Ax7BTWZJqS/A== X-Google-Smtp-Source: APBJJlEWE4/oqx5RsVcilzfJv1moiSezBIDuQGa3SuvWo4OoqpnluhQUZA74Uo7n46yKjcXQByvXvw== X-Received: by 2002:a05:6870:f589:b0:1b4:685d:55e4 with SMTP id eh9-20020a056870f58900b001b4685d55e4mr14637846oab.39.1689689757444; Tue, 18 Jul 2023 07:15:57 -0700 (PDT) Received: from mandiga.. ([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.55 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:15:56 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 4/6] stdlib: Implement introsort for qsort (BZ 19305) Date: Tue, 18 Jul 2023 11:15:41 -0300 Message-Id: <20230718141543.3925254-5-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" This patch makes the quicksort implementation to acts as introsort, to avoid worse-case performance (and thus making it O(nlog n)). It switch to heapsort when the depth level reaches 2*log2(total elements). The heapsort is a textbook implementation. Checked on x86_64-linux-gnu. --- stdlib/qsort.c | 85 ++++++++++++++++++++++++++++++++++++++++++++++---- 1 file changed, 79 insertions(+), 6 deletions(-) diff --git a/stdlib/qsort.c b/stdlib/qsort.c index 640896a598..054c900b02 100644 --- a/stdlib/qsort.c +++ b/stdlib/qsort.c @@ -119,6 +119,7 @@ typedef struct { char *lo; char *hi; + size_t depth; } stack_node; /* The stack needs log (total_elements) entries (we could even subtract @@ -128,22 +129,83 @@ typedef struct enum { STACK_SIZE = CHAR_BIT * sizeof (size_t) }; static inline stack_node * -push (stack_node *top, char *lo, char *hi) +push (stack_node *top, char *lo, char *hi, size_t depth) { top->lo = lo; top->hi = hi; + top->depth = depth; return ++top; } static inline stack_node * -pop (stack_node *top, char **lo, char **hi) +pop (stack_node *top, char **lo, char **hi, size_t *depth) { --top; *lo = top->lo; *hi = top->hi; + *depth = top->depth; return top; } +/* A fast, small, non-recursive O(nlog n) heapsort, adapted from Linux + lib/sort.c. Used on introsort implementation as a fallback routine with + worst-case performance of O(nlog n) and worst-case space complexity of + O(1). */ + +static inline void +siftdown (void *base, size_t size, size_t k, size_t n, + enum swap_type_t swap_type, __compar_d_fn_t cmp, void *arg) +{ + while (k <= n / 2) + { + size_t j = 2 * k; + if (j < n && cmp (base + (j * size), base + ((j + 1) * size), arg) < 0) + j++; + + if (cmp (base + (k * size), base + (j * size), arg) >= 0) + break; + + do_swap (base + (size * j), base + (k * size), size, swap_type); + k = j; + } +} + +static inline void +heapify (void *base, size_t size, size_t n, enum swap_type_t swap_type, + __compar_d_fn_t cmp, void *arg) +{ + size_t k = n / 2; + while (1) + { + siftdown (base, size, k, n, swap_type, cmp, arg); + if (k-- == 0) + break; + } +} + +static void +heapsort_r (void *base, void *end, size_t size, enum swap_type_t swap_type, + __compar_d_fn_t cmp, void *arg) +{ + const size_t count = ((uintptr_t) end - (uintptr_t) base) / size; + + if (count < 2) + return; + + size_t n = count - 1; + + /* Build the binary heap, largest value at the base[0]. */ + heapify (base, size, n, swap_type, cmp, arg); + + /* On each iteration base[0:n] is the binary heap, while base[n:count] + is sorted. */ + while (n > 0) + { + do_swap (base, base + (n * size), size, swap_type); + n--; + siftdown (base, size, 0, n, swap_type, cmp, arg); + } +} /* Order size using quicksort. This implementation incorporates four optimizations discussed in Sedgewick: @@ -229,7 +291,7 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, const size_t max_thresh = MAX_THRESH * size; - if (total_elems == 0) + if (total_elems <= 1) /* Avoid lossage with unsigned arithmetic below. */ return; @@ -241,6 +303,10 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, else swap_type = SWAP_BYTES; + /* Maximum depth before quicksort switches to heapsort. */ + size_t depth = 2 * (sizeof (size_t) * CHAR_BIT - 1 + - __builtin_clzl (total_elems)); + if (total_elems > MAX_THRESH) { char *lo = base_ptr; @@ -250,6 +316,13 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, while (stack < top) { + if (depth == 0) + { + heapsort_r (lo, hi, size, swap_type, cmp, arg); + top = pop (top, &lo, &hi, &depth); + continue; + } + char *left_ptr; char *right_ptr; @@ -313,7 +386,7 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, { if ((size_t) (hi - left_ptr) <= max_thresh) /* Ignore both small partitions. */ - top = pop (top, &lo, &hi); + top = pop (top, &lo, &hi, &depth); else /* Ignore small left partition. */ lo = left_ptr; @@ -324,13 +397,13 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, else if ((right_ptr - lo) > (hi - left_ptr)) { /* Push larger left partition indices. */ - top = push (top, lo, right_ptr); + top = push (top, lo, right_ptr, depth - 1); lo = left_ptr; } else { /* Push larger right partition indices. */ - top = push (top, left_ptr, hi); + top = push (top, left_ptr, hi, depth - 1); hi = right_ptr; } } From patchwork Tue Jul 18 14:15:42 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809315 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=server2.sourceware.org; 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([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.57 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:15:58 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 5/6] stdlib: Remove use of mergesort on qsort (BZ 21719) Date: Tue, 18 Jul 2023 11:15:42 -0300 Message-Id: <20230718141543.3925254-6-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" This patch removes the mergesort optimization on qsort implementation and uses the introsort instead. The mergesort implementation has some issues: - It is as-safe only for certain types sizes (if total size is less than 1 KB with large element sizes also forcing memory allocation) which contradicts the function documentation. Although not required by the C standard, it is preferable and doable to have an O(1) space implementation. - The malloc for certain element size and element number adds arbitrary latency (might even be worse if malloc is interposed). - To avoid trigger swap from memory allocation the implementation relies on system information that might be virtualized (for instance VMs with overcommit memory) which might lead to potentially use of swap even if system advertise more memory than actually has. The check also have the downside of issuing syscalls where none is expected (although only once per execution). - The mergesort is suboptimal on an already sorted array (BZ#21719). The introsort implementation is already optimized to use constant extra space (due to the limit of total number of elements from maximum VM size) and thus can be used to avoid the malloc usage issues. Resulting performance is slower due the usage of qsort, specially in the worst-case scenario (partialy or sorted arrays) and due the fact mergesort uses a slight improved swap operations. This change also renders the BZ#21719 fix unrequired (since it is meant to fix the sorted input performance degradation for mergesort). The manual is also updated to indicate the function is now async-cancel safe. Checked on x86_64-linux-gnu. --- include/stdlib.h | 2 - manual/argp.texi | 2 +- manual/locale.texi | 3 +- manual/search.texi | 7 +- stdlib/Makefile | 2 - stdlib/msort.c | 309 --------------------------------------------- stdlib/qsort.c | 14 +- 7 files changed, 16 insertions(+), 323 deletions(-) delete mode 100644 stdlib/msort.c diff --git a/include/stdlib.h b/include/stdlib.h index 7deb8193d7..7b421f1bb3 100644 --- a/include/stdlib.h +++ b/include/stdlib.h @@ -147,8 +147,6 @@ extern int __posix_openpt (int __oflag) attribute_hidden; extern int __add_to_environ (const char *name, const char *value, const char *combines, int replace) attribute_hidden; -extern void _quicksort (void *const pbase, size_t total_elems, - size_t size, __compar_d_fn_t cmp, void *arg); extern int __on_exit (void (*__func) (int __status, void *__arg), void *__arg); diff --git a/manual/argp.texi b/manual/argp.texi index 0023441812..b77ad68285 100644 --- a/manual/argp.texi +++ b/manual/argp.texi @@ -735,7 +735,7 @@ for options, bad phase of the moon, etc. @c hol_set_group ok @c hol_find_entry ok @c hol_sort @mtslocale @acucorrupt -@c qsort dup @acucorrupt +@c qsort dup @c hol_entry_qcmp @mtslocale @c hol_entry_cmp @mtslocale @c group_cmp ok diff --git a/manual/locale.texi b/manual/locale.texi index 720e0ca952..f6afa5dc44 100644 --- a/manual/locale.texi +++ b/manual/locale.texi @@ -253,7 +253,7 @@ The symbols in this section are defined in the header file @file{locale.h}. @c calculate_head_size ok @c __munmap ok @c compute_hashval ok -@c qsort dup @acucorrupt +@c qsort dup @c rangecmp ok @c malloc @ascuheap @acsmem @c strdup @ascuheap @acsmem @@ -275,7 +275,6 @@ The symbols in this section are defined in the header file @file{locale.h}. @c realloc @ascuheap @acsmem @c realloc @ascuheap @acsmem @c fclose @ascuheap @asulock @acsmem @acsfd @aculock -@c qsort @ascuheap @acsmem @c alias_compare dup @c libc_lock_unlock @aculock @c _nl_explode_name @ascuheap @acsmem diff --git a/manual/search.texi b/manual/search.texi index 5691bf2f2b..a550858478 100644 --- a/manual/search.texi +++ b/manual/search.texi @@ -159,7 +159,7 @@ To sort an array using an arbitrary comparison function, use the @deftypefun void qsort (void *@var{array}, size_t @var{count}, size_t @var{size}, comparison_fn_t @var{compare}) @standards{ISO, stdlib.h} -@safety{@prelim{}@mtsafe{}@assafe{}@acunsafe{@acucorrupt{}}} +@safety{@prelim{}@mtsafe{}@assafe{}@acsafe{}} The @code{qsort} function sorts the array @var{array}. The array contains @var{count} elements, each of which is of size @var{size}. @@ -199,9 +199,8 @@ Functions}): The @code{qsort} function derives its name from the fact that it was originally implemented using the ``quick sort'' algorithm. -The implementation of @code{qsort} in this library might not be an -in-place sort and might thereby use an extra amount of memory to store -the array. +The implementation of @code{qsort} in this library is an in-place sort +and uses a constant extra space (allocated on the stack). @end deftypefun @node Search/Sort Example diff --git a/stdlib/Makefile b/stdlib/Makefile index 25e42a77e7..095518eef4 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -96,7 +96,6 @@ routines := \ mbtowc \ mrand48 \ mrand48_r \ - msort \ nrand48 \ nrand48_r \ old_atexit \ @@ -380,7 +379,6 @@ generated += \ # generated CFLAGS-bsearch.c += $(uses-callbacks) -CFLAGS-msort.c += $(uses-callbacks) CFLAGS-qsort.c += $(uses-callbacks) CFLAGS-system.c += -fexceptions CFLAGS-system.os = -fomit-frame-pointer diff --git a/stdlib/msort.c b/stdlib/msort.c deleted file mode 100644 index bbaa5e9f82..0000000000 --- a/stdlib/msort.c +++ /dev/null @@ -1,309 +0,0 @@ -/* An alternative to qsort, with an identical interface. - This file is part of the GNU C Library. - Copyright (C) 1992-2023 Free Software Foundation, Inc. - - The GNU C Library is free software; you can redistribute it and/or - modify it under the terms of the GNU Lesser General Public - License as published by the Free Software Foundation; either - version 2.1 of the License, or (at your option) any later version. - - The GNU C Library is distributed in the hope that it will be useful, - but WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - Lesser General Public License for more details. - - You should have received a copy of the GNU Lesser General Public - License along with the GNU C Library; if not, see - . */ - -#include -#include -#include -#include -#include -#include -#include -#include - -struct msort_param -{ - size_t s; - size_t var; - __compar_d_fn_t cmp; - void *arg; - char *t; -}; -static void msort_with_tmp (const struct msort_param *p, void *b, size_t n); - -static void -msort_with_tmp (const struct msort_param *p, void *b, size_t n) -{ - char *b1, *b2; - size_t n1, n2; - - if (n <= 1) - return; - - n1 = n / 2; - n2 = n - n1; - b1 = b; - b2 = (char *) b + (n1 * p->s); - - msort_with_tmp (p, b1, n1); - msort_with_tmp (p, b2, n2); - - char *tmp = p->t; - const size_t s = p->s; - __compar_d_fn_t cmp = p->cmp; - void *arg = p->arg; - switch (p->var) - { - case 0: - while (n1 > 0 && n2 > 0) - { - if ((*cmp) (b1, b2, arg) <= 0) - { - *(uint32_t *) tmp = *(uint32_t *) b1; - b1 += sizeof (uint32_t); - --n1; - } - else - { - *(uint32_t *) tmp = *(uint32_t *) b2; - b2 += sizeof (uint32_t); - --n2; - } - tmp += sizeof (uint32_t); - } - break; - case 1: - while (n1 > 0 && n2 > 0) - { - if ((*cmp) (b1, b2, arg) <= 0) - { - *(uint64_t *) tmp = *(uint64_t *) b1; - b1 += sizeof (uint64_t); - --n1; - } - else - { - *(uint64_t *) tmp = *(uint64_t *) b2; - b2 += sizeof (uint64_t); - --n2; - } - tmp += sizeof (uint64_t); - } - break; - case 2: - while (n1 > 0 && n2 > 0) - { - unsigned long *tmpl = (unsigned long *) tmp; - unsigned long *bl; - - tmp += s; - if ((*cmp) (b1, b2, arg) <= 0) - { - bl = (unsigned long *) b1; - b1 += s; - --n1; - } - else - { - bl = (unsigned long *) b2; - b2 += s; - --n2; - } - while (tmpl < (unsigned long *) tmp) - *tmpl++ = *bl++; - } - break; - case 3: - while (n1 > 0 && n2 > 0) - { - if ((*cmp) (*(const void **) b1, *(const void **) b2, arg) <= 0) - { - *(void **) tmp = *(void **) b1; - b1 += sizeof (void *); - --n1; - } - else - { - *(void **) tmp = *(void **) b2; - b2 += sizeof (void *); - --n2; - } - tmp += sizeof (void *); - } - break; - default: - while (n1 > 0 && n2 > 0) - { - if ((*cmp) (b1, b2, arg) <= 0) - { - tmp = (char *) __mempcpy (tmp, b1, s); - b1 += s; - --n1; - } - else - { - tmp = (char *) __mempcpy (tmp, b2, s); - b2 += s; - --n2; - } - } - break; - } - - if (n1 > 0) - memcpy (tmp, b1, n1 * s); - memcpy (b, p->t, (n - n2) * s); -} - - -void -__qsort_r (void *b, size_t n, size_t s, __compar_d_fn_t cmp, void *arg) -{ - size_t size = n * s; - char *tmp = NULL; - struct msort_param p; - - /* For large object sizes use indirect sorting. */ - if (s > 32) - size = 2 * n * sizeof (void *) + s; - - if (size < 1024) - /* The temporary array is small, so put it on the stack. */ - p.t = __alloca (size); - else - { - /* We should avoid allocating too much memory since this might - have to be backed up by swap space. */ - static long int phys_pages; - static int pagesize; - - if (pagesize == 0) - { - phys_pages = __sysconf (_SC_PHYS_PAGES); - - if (phys_pages == -1) - /* Error while determining the memory size. So let's - assume there is enough memory. Otherwise the - implementer should provide a complete implementation of - the `sysconf' function. */ - phys_pages = (long int) (~0ul >> 1); - - /* The following determines that we will never use more than - a quarter of the physical memory. */ - phys_pages /= 4; - - /* Make sure phys_pages is written to memory. */ - atomic_write_barrier (); - - pagesize = __sysconf (_SC_PAGESIZE); - } - - /* Just a comment here. We cannot compute - phys_pages * pagesize - and compare the needed amount of memory against this value. - The problem is that some systems might have more physical - memory then can be represented with a `size_t' value (when - measured in bytes. */ - - /* If the memory requirements are too high don't allocate memory. */ - if (size / pagesize > (size_t) phys_pages) - { - _quicksort (b, n, s, cmp, arg); - return; - } - - /* It's somewhat large, so malloc it. */ - int save = errno; - tmp = malloc (size); - __set_errno (save); - if (tmp == NULL) - { - /* Couldn't get space, so use the slower algorithm - that doesn't need a temporary array. */ - _quicksort (b, n, s, cmp, arg); - return; - } - p.t = tmp; - } - - p.s = s; - p.var = 4; - p.cmp = cmp; - p.arg = arg; - - if (s > 32) - { - /* Indirect sorting. */ - char *ip = (char *) b; - void **tp = (void **) (p.t + n * sizeof (void *)); - void **t = tp; - void *tmp_storage = (void *) (tp + n); - - while ((void *) t < tmp_storage) - { - *t++ = ip; - ip += s; - } - p.s = sizeof (void *); - p.var = 3; - msort_with_tmp (&p, p.t + n * sizeof (void *), n); - - /* tp[0] .. tp[n - 1] is now sorted, copy around entries of - the original array. Knuth vol. 3 (2nd ed.) exercise 5.2-10. */ - char *kp; - size_t i; - for (i = 0, ip = (char *) b; i < n; i++, ip += s) - if ((kp = tp[i]) != ip) - { - size_t j = i; - char *jp = ip; - memcpy (tmp_storage, ip, s); - - do - { - size_t k = (kp - (char *) b) / s; - tp[j] = jp; - memcpy (jp, kp, s); - j = k; - jp = kp; - kp = tp[k]; - } - while (kp != ip); - - tp[j] = jp; - memcpy (jp, tmp_storage, s); - } - } - else - { - if ((s & (sizeof (uint32_t) - 1)) == 0 - && ((uintptr_t) b) % __alignof__ (uint32_t) == 0) - { - if (s == sizeof (uint32_t)) - p.var = 0; - else if (s == sizeof (uint64_t) - && ((uintptr_t) b) % __alignof__ (uint64_t) == 0) - p.var = 1; - else if ((s & (sizeof (unsigned long) - 1)) == 0 - && ((uintptr_t) b) - % __alignof__ (unsigned long) == 0) - p.var = 2; - } - msort_with_tmp (&p, b, n); - } - free (tmp); -} -libc_hidden_def (__qsort_r) -weak_alias (__qsort_r, qsort_r) - - -void -qsort (void *b, size_t n, size_t s, __compar_fn_t cmp) -{ - return __qsort_r (b, n, s, (__compar_d_fn_t) cmp, NULL); -} -libc_hidden_def (qsort) diff --git a/stdlib/qsort.c b/stdlib/qsort.c index 054c900b02..120edde573 100644 --- a/stdlib/qsort.c +++ b/stdlib/qsort.c @@ -19,7 +19,6 @@ Engineering a sort function; Jon Bentley and M. Douglas McIlroy; Software - Practice and Experience; Vol. 23 (11), 1249-1265, 1993. */ -#include #include #include #include @@ -284,8 +283,8 @@ insertion_sort_qsort_partitions (void *const pbase, size_t total_elems, } void -_quicksort (void *const pbase, size_t total_elems, size_t size, - __compar_d_fn_t cmp, void *arg) +__qsort_r (void *const pbase, size_t total_elems, size_t size, + __compar_d_fn_t cmp, void *arg) { char *base_ptr = (char *) pbase; @@ -417,3 +416,12 @@ _quicksort (void *const pbase, size_t total_elems, size_t size, insertion_sort_qsort_partitions (pbase, total_elems, size, swap_type, cmp, arg); } +libc_hidden_def (__qsort_r) +weak_alias (__qsort_r, qsort_r) + +void +qsort (void *b, size_t n, size_t s, __compar_fn_t cmp) +{ + return __qsort_r (b, n, s, (__compar_d_fn_t) cmp, NULL); +} +libc_hidden_def (qsort) From patchwork Tue Jul 18 14:15:43 2023 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Adhemerval Zanella Netto X-Patchwork-Id: 1809312 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@legolas.ozlabs.org Authentication-Results: legolas.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=sourceware.org (client-ip=2620:52:3:1:0:246e:9693:128c; helo=server2.sourceware.org; envelope-from=libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org; receiver=) Authentication-Results: legolas.ozlabs.org; dkim=pass (1024-bit key; secure) header.d=sourceware.org header.i=@sourceware.org header.a=rsa-sha256 header.s=default header.b=tKfeqvSF; dkim-atps=neutral Received: from server2.sourceware.org (server2.sourceware.org [IPv6:2620:52:3:1:0:246e:9693:128c]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-384) server-digest SHA384) (No client certificate requested) by legolas.ozlabs.org (Postfix) with ESMTPS id 4R51H3143Yz20FX for ; Wed, 19 Jul 2023 00:17:03 +1000 (AEST) Received: from server2.sourceware.org (localhost [IPv6:::1]) by sourceware.org (Postfix) with ESMTP id 0533C3870C09 for ; Tue, 18 Jul 2023 14:17:01 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 0533C3870C09 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1689689821; bh=jPzPvGBCOsxIPuQah7PCdfdx8LtqR5cWHy8OXSxn8qQ=; h=To:Subject:Date:In-Reply-To:References:List-Id:List-Unsubscribe: List-Archive:List-Post:List-Help:List-Subscribe:From:Reply-To: From; b=tKfeqvSFme+gzTwBi4p8Kpojb25eoR8bzFMZWJ0uF7IzFTe1MJr9z0b3kCVJCVXT9 N+vEWhAzuUjWM5E4neJ7UfnBX4HpoFztxYZVXMZAQImcPhkXhwg3Pr5SG7Ton2kZXe VaS8aYz94I16ciwxmWhL8aNKg+kRkd20gQtdITVo= X-Original-To: libc-alpha@sourceware.org Delivered-To: libc-alpha@sourceware.org Received: from mail-oa1-x2a.google.com (mail-oa1-x2a.google.com [IPv6:2001:4860:4864:20::2a]) by sourceware.org (Postfix) with ESMTPS id 57DF63856DEA for ; Tue, 18 Jul 2023 14:16:03 +0000 (GMT) DMARC-Filter: OpenDMARC Filter v1.4.2 sourceware.org 57DF63856DEA Received: by mail-oa1-x2a.google.com with SMTP id 586e51a60fabf-1b0156a1c4bso3381391fac.1 for ; Tue, 18 Jul 2023 07:16:03 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1689689762; x=1690294562; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=jPzPvGBCOsxIPuQah7PCdfdx8LtqR5cWHy8OXSxn8qQ=; b=gYO23d5BOF+rsOfTQ+JSwxFbTXuo+P5i6d/EZ2pJ3cFLoNWrnxBtJesgqYScvRRlox vLWmRkMcaOVYmGCHrMKXLmoURfutAl37VDgo/EIhrDRYemtgc1nKdwJfltYuUbWdp7t4 PEphptEAwjta65fGOtSUYqL2ZlxmdlCWCnLxHN7Acl2quukqlKFR3TgnRzeheO6CfIq9 9DVNfS2CR62wQqwZXtI9K2iN5VkoQZiXkoQSCrewGGl4Ie8EPp0zTIHs+dpKJNNcl9JE EYdd2Tee2C/KGfr7+MV5ZjvFQHKC9dB+duJP6wsfNnI2gt1/zcZQrt9yHIMWkF0QgAwM JnQw== X-Gm-Message-State: ABy/qLa+yHlmSaQXZahf+mtYXqmPVBQAF2OmzTMc61QzvavPmwhftKPR WhGa7ma4y2r8lHNs/GL1KLNqrqrcnatEBuXOkTU5bQ== X-Google-Smtp-Source: APBJJlEGaKW9daqNPNZu10ps16Nkoz1LufNSzq1UtFwGpyAiYjlOXFsxzeZpJq3V3QAOtmbm/Rt5zg== X-Received: by 2002:a05:6870:64aa:b0:1b0:e98:163b with SMTP id cz42-20020a05687064aa00b001b00e98163bmr13887026oab.21.1689689761833; Tue, 18 Jul 2023 07:16:01 -0700 (PDT) Received: from mandiga.. ([2804:1b3:a7c0:5656:745f:3154:510d:b668]) by smtp.gmail.com with ESMTPSA id 188-20020a4a11c5000000b00565fcfabab8sm847843ooc.21.2023.07.18.07.15.59 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Tue, 18 Jul 2023 07:16:01 -0700 (PDT) To: libc-alpha@sourceware.org, Paul Eggert , Alexander Monakov Subject: [PATCH v6 6/6] stdlib: Add more qsort{_r} coverage Date: Tue, 18 Jul 2023 11:15:43 -0300 Message-Id: <20230718141543.3925254-7-adhemerval.zanella@linaro.org> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> References: <20230718141543.3925254-1-adhemerval.zanella@linaro.org> MIME-Version: 1.0 X-Spam-Status: No, score=-12.6 required=5.0 tests=BAYES_00, DKIM_SIGNED, DKIM_VALID, DKIM_VALID_AU, DKIM_VALID_EF, GIT_PATCH_0, KAM_SHORT, RCVD_IN_DNSWL_NONE, SPF_HELO_NONE, SPF_PASS, TXREP, 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: 2.1.29 Precedence: list List-Id: Libc-alpha mailing list List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-Patchwork-Original-From: Adhemerval Zanella via Libc-alpha From: Adhemerval Zanella Netto Reply-To: Adhemerval Zanella Errors-To: libc-alpha-bounces+incoming=patchwork.ozlabs.org@sourceware.org Sender: "Libc-alpha" This patch adds a qsort and qsort_r to trigger the worst case scenario for the quicksort (which glibc current lacks coverage). The test is done with random input, dfferent internal types (uint8_t, uint16_t, uint32_t, uint64_t, large size), and with different set of element numbers (from 0 to 17384). Checked on x86_64-linux-gnu and i686-linux-gnu. --- stdlib/Makefile | 1 + stdlib/tst-qsort3.c | 298 ++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 299 insertions(+) create mode 100644 stdlib/tst-qsort3.c diff --git a/stdlib/Makefile b/stdlib/Makefile index 095518eef4..6af606136e 100644 --- a/stdlib/Makefile +++ b/stdlib/Makefile @@ -214,6 +214,7 @@ tests := \ tst-on_exit \ tst-qsort \ tst-qsort2 \ + tst-qsort3 \ tst-quick_exit \ tst-rand48 \ tst-rand48-2 \ diff --git a/stdlib/tst-qsort3.c b/stdlib/tst-qsort3.c new file mode 100644 index 0000000000..6940540289 --- /dev/null +++ b/stdlib/tst-qsort3.c @@ -0,0 +1,298 @@ +/* qsort(_r) tests to trigger worst case for quicksort. + Copyright (C) 2023 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + . */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +typedef enum +{ + Sorted, + Random, + Repeated, + Bitonic +} arraytype_t; + +/* Ratio of total of elements which will be repeated. */ +static const double RepeatedRatio = 0.2; + +struct array_t +{ + arraytype_t type; + const char *name; +} static const arraytypes[] = +{ + { Sorted, "Sorted" }, + { Random, "Random" }, + { Repeated, "Repeated" }, + { Bitonic, "Bitonic" }, +}; + +/* Return the index of BASE as interpreted as an array of elements + of size SIZE. */ +static inline void * +arr (void *base, size_t idx, size_t size) +{ + return (void*)((uintptr_t)base + (idx * size)); +} + +/* Functions used to check qsort. */ +static int +uint8_t_cmp (const void *a, const void *b) +{ + uint8_t ia = *(uint8_t*)a; + uint8_t ib = *(uint8_t*)b; + return (ia > ib) - (ia < ib); +} + +static int +uint16_t_cmp (const void *a, const void *b) +{ + uint16_t ia = *(uint16_t*)a; + uint16_t ib = *(uint16_t*)b; + return (ia > ib) - (ia < ib); +} + +static int +uint32_t_cmp (const void *a, const void *b) +{ + uint32_t ia = *(uint32_t*)a; + uint32_t ib = *(uint32_t*)b; + return (ia > ib) - (ia < ib); +} + +static int +uint64_t_cmp (const void *a, const void *b) +{ + uint64_t ia = *(uint64_t*)a; + uint64_t ib = *(uint64_t*)b; + return (ia > ib) - (ia < ib); +} + +#define LARGE_SIZE 48 + +static int +large_cmp (const void *a, const void *b) +{ + return memcmp (a, b, LARGE_SIZE); +} + +/* Function used to check qsort_r. */ +typedef enum +{ + UINT8_CMP_T, + UINT16_CMP_T, + UINT32_CMP_T, + UINT64_CMP_T, + LARGE_CMP_T +} type_cmp_t; + +static type_cmp_t +uint_t_cmp_type (size_t sz) +{ + switch (sz) + { + case sizeof (uint8_t): return UINT8_CMP_T; + case sizeof (uint16_t): return UINT16_CMP_T; + case sizeof (uint64_t): return UINT64_CMP_T; + case sizeof (uint32_t): return UINT32_CMP_T; + default: return LARGE_CMP_T; + } +} + +static int +uint_t_cmp (const void *a, const void *b, void *arg) +{ + type_cmp_t type = *(type_cmp_t*) arg; + switch (type) + { + case UINT8_CMP_T: return uint8_t_cmp (a, b); + case UINT32_CMP_T: return uint32_t_cmp (a, b); + case UINT16_CMP_T: return uint16_t_cmp (a, b); + case UINT64_CMP_T: return uint64_t_cmp (a, b); + default: return large_cmp (a, b); + } +} + +static void +seq (void *elem, size_t type_size, int value) +{ + if (type_size == sizeof (uint8_t)) + *(uint8_t*)elem = value; + else if (type_size == sizeof (uint16_t)) + *(uint16_t*)elem = value; + else if (type_size == sizeof (uint32_t)) + *(uint32_t*)elem = value; + else if (type_size == sizeof (uint64_t)) + *(uint64_t*)elem = value; + else + memset (elem, value, type_size); +} + +static void * +create_array (size_t nmemb, size_t type_size, arraytype_t type) +{ + size_t size = nmemb * type_size; + void *array = xmalloc (size); + + switch (type) + { + case Sorted: + for (size_t i = 0; i < nmemb; i++) + seq (arr (array, i, type_size), type_size, i); + break; + + case Random: + arc4random_buf (array, size); + break; + + case Repeated: + { + arc4random_buf (array, size); + + void *randelem = xmalloc (type_size); + arc4random_buf (randelem, type_size); + + /* Repeat REPEATED elements (based on RepeatRatio ratio) in the random + array. */ + size_t repeated = (size_t)(nmemb * RepeatedRatio); + for (size_t i = 0; i < repeated; i++) + { + size_t pos = arc4random_uniform (nmemb - 1); + memcpy (arr (array, pos, type_size), randelem, type_size); + } + free (randelem); + } + break; + + case Bitonic: + { + size_t i; + for (i = 0; i < nmemb / 2; i++) + seq (arr (array, i, type_size), type_size, i); + for ( ; i < nmemb; i++) + seq (arr (array, i, type_size), type_size, (nmemb - 1) - i); + } + break; + } + + return array; +} + +typedef int (*cmpfunc_t)(const void *, const void *); + +/* Check if ARRAY of total NMEMB element of size SIZE is sorted + based on CMPFUNC. */ +static void +check_array (void *array, size_t nmemb, size_t type_size, + cmpfunc_t cmpfunc) +{ + for (size_t i = 1; i < nmemb; i++) + { + int ret = cmpfunc (arr (array, i, type_size), + arr (array, i-1, type_size)); + TEST_VERIFY_EXIT (ret >= 0); + } +} + +static void +check_qsort (size_t nelem, size_t type_size, arraytype_t type, + cmpfunc_t cmpfunc) +{ + void *array = create_array (nelem, type_size, type); + + qsort (array, nelem, type_size, cmpfunc); + + check_array (array, nelem, type_size, cmpfunc); + + free (array); +} + +static void +check_qsort_r (size_t nelem, size_t type_size, arraytype_t type, + cmpfunc_t cmpfunc) +{ + void *array = create_array (nelem, type_size, type); + + type_cmp_t typecmp = uint_t_cmp_type (type_size); + qsort_r (array, nelem, type_size, uint_t_cmp, &typecmp); + + check_array (array, nelem, type_size, cmpfunc); + + free (array); +} + +static int +do_test (void) +{ + /* Some random sizes. */ + const size_t nelems[] = { 0, 1, 7, 20, 32, 100, 256, 1024, 8560, 17384 }; + + struct test_t + { + size_t type_size; + cmpfunc_t cmpfunc; + } + const tests[] = + { + { sizeof (uint8_t), uint8_t_cmp }, + { sizeof (uint16_t), uint16_t_cmp }, + { sizeof (uint32_t), uint32_t_cmp }, + { sizeof (uint64_t), uint64_t_cmp }, + /* Test swap with large elements. */ + { LARGE_SIZE, large_cmp }, + }; + + for (const struct test_t *test = tests; test < array_end (tests); ++test) + { + if (test_verbose > 0) + printf ("info: testing qsort with type_size=%zu\n", test->type_size); + for (const struct array_t *arraytype = arraytypes; + arraytype < array_end (arraytypes); + ++arraytype) + { + if (test_verbose > 0) + printf (" distribution=%s\n", arraytype->name); + for (const size_t *nelem = nelems; + nelem < array_end (nelems); + ++nelem) + { + if (test_verbose > 0) + printf (" i nelem=%zu, total size=%zu\n", *nelem, + *nelem * test->type_size); + + check_qsort (*nelem, test->type_size, arraytype->type, + test->cmpfunc); + check_qsort_r (*nelem, test->type_size, arraytype->type, + test->cmpfunc); + } + } + } + + return 0; +} + +#include