From 4b1a3992de7803d4c082867ea1168efeaa85cc5d Mon Sep 17 00:00:00 2001 From: Xin Li Date: Fri, 19 May 2017 10:13:08 -0700 Subject: [PATCH] libc: Sync qsort(3) with FreeBSD revision r318515. r279663: enhance to handle 32-bit aligned data on 64-bit systems r279666: qsort(3): small style(9) cleanups. r288030: Use ANSI C prototypes. Eliminates -Wold-style-definition warnings. r318514: Use size_t. r318515: Reduce the possible recursion level to log2(N) by always recursing on the smaller partition instead. Bug: 38450217 Test: builds, ./tests/run-on-host.sh 64 Change-Id: Ieb622e6f54f8f6d6f62e1bdb491d3b5c8e2f9965 --- libc/upstream-freebsd/lib/libc/stdlib/qsort.c | 102 ++++++++++++++++--------- tests/Android.bp | 1 + tests/qsort_test.cpp | 106 ++++++++++++++++++++++++++ 3 files changed, 173 insertions(+), 36 deletions(-) create mode 100644 tests/qsort_test.cpp diff --git a/libc/upstream-freebsd/lib/libc/stdlib/qsort.c b/libc/upstream-freebsd/lib/libc/stdlib/qsort.c index 93e22cdf9..1ccc518d3 100644 --- a/libc/upstream-freebsd/lib/libc/stdlib/qsort.c +++ b/libc/upstream-freebsd/lib/libc/stdlib/qsort.c @@ -41,47 +41,53 @@ typedef int cmp_t(void *, const void *, const void *); typedef int cmp_t(const void *, const void *); #endif static inline char *med3(char *, char *, char *, cmp_t *, void *); -static inline void swapfunc(char *, char *, int, int); +static inline void swapfunc(char *, char *, size_t, int, int); -#define min(a, b) (a) < (b) ? a : b +#define MIN(a, b) ((a) < (b) ? a : b) /* * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function". */ -#define swapcode(TYPE, parmi, parmj, n) { \ - long i = (n) / sizeof (TYPE); \ - TYPE *pi = (TYPE *) (parmi); \ - TYPE *pj = (TYPE *) (parmj); \ +#define swapcode(TYPE, parmi, parmj, n) { \ + size_t i = (n) / sizeof (TYPE); \ + TYPE *pi = (TYPE *) (parmi); \ + TYPE *pj = (TYPE *) (parmj); \ do { \ TYPE t = *pi; \ *pi++ = *pj; \ *pj++ = t; \ - } while (--i > 0); \ + } while (--i > 0); \ } -#define SWAPINIT(a, es) swaptype = ((char *)a - (char *)0) % sizeof(long) || \ - es % sizeof(long) ? 2 : es == sizeof(long)? 0 : 1; +#define SWAPINIT(TYPE, a, es) swaptype_ ## TYPE = \ + ((char *)a - (char *)0) % sizeof(TYPE) || \ + es % sizeof(TYPE) ? 2 : es == sizeof(TYPE) ? 0 : 1; static inline void -swapfunc(a, b, n, swaptype) - char *a, *b; - int n, swaptype; +swapfunc(char *a, char *b, size_t n, int swaptype_long, int swaptype_int) { - if(swaptype <= 1) + if (swaptype_long <= 1) swapcode(long, a, b, n) + else if (swaptype_int <= 1) + swapcode(int, a, b, n) else swapcode(char, a, b, n) } -#define swap(a, b) \ - if (swaptype == 0) { \ +#define swap(a, b) \ + if (swaptype_long == 0) { \ long t = *(long *)(a); \ *(long *)(a) = *(long *)(b); \ *(long *)(b) = t; \ + } else if (swaptype_int == 0) { \ + int t = *(int *)(a); \ + *(int *)(a) = *(int *)(b); \ + *(int *)(b) = t; \ } else \ - swapfunc(a, b, es, swaptype) + swapfunc(a, b, es, swaptype_long, swaptype_int) -#define vecswap(a, b, n) if ((n) > 0) swapfunc(a, b, n, swaptype) +#define vecswap(a, b, n) \ + if ((n) > 0) swapfunc(a, b, n, swaptype_long, swaptype_int) #ifdef I_AM_QSORT_R #define CMP(t, x, y) (cmp((t), (x), (y))) @@ -98,24 +104,25 @@ __unused { return CMP(thunk, a, b) < 0 ? (CMP(thunk, b, c) < 0 ? b : (CMP(thunk, a, c) < 0 ? c : a )) - :(CMP(thunk, b, c) > 0 ? b : (CMP(thunk, a, c) < 0 ? a : c )); + :(CMP(thunk, b, c) > 0 ? b : (CMP(thunk, a, c) < 0 ? a : c )); } #ifdef I_AM_QSORT_R void qsort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp) #else -#define thunk NULL +#define thunk NULL void qsort(void *a, size_t n, size_t es, cmp_t *cmp) #endif { char *pa, *pb, *pc, *pd, *pl, *pm, *pn; - size_t d, r; + size_t d1, d2; int cmp_result; - int swaptype, swap_cnt; + int swaptype_long, swaptype_int, swap_cnt; -loop: SWAPINIT(a, es); +loop: SWAPINIT(long, a, es); + SWAPINIT(int, a, es); swap_cnt = 0; if (n < 7) { for (pm = (char *)a + es; pm < (char *)a + n * es; pm += es) @@ -130,7 +137,8 @@ loop: SWAPINIT(a, es); pl = a; pn = (char *)a + (n - 1) * es; if (n > 40) { - d = (n / 8) * es; + size_t d = (n / 8) * es; + pl = med3(pl, pl + d, pl + 2 * d, cmp, thunk); pm = med3(pm - d, pm, pm + d, cmp, thunk); pn = med3(pn - 2 * d, pn - d, pn, cmp, thunk); @@ -175,21 +183,43 @@ loop: SWAPINIT(a, es); } pn = (char *)a + n * es; - r = min(pa - (char *)a, pb - pa); - vecswap(a, pb - r, r); - r = min(pd - pc, pn - pd - es); - vecswap(pb, pn - r, r); - if ((r = pb - pa) > es) + d1 = MIN(pa - (char *)a, pb - pa); + vecswap(a, pb - d1, d1); + d1 = MIN(pd - pc, pn - pd - es); + vecswap(pb, pn - d1, d1); + + d1 = pb - pa; + d2 = pd - pc; + if (d1 <= d2) { + /* Recurse on left partition, then iterate on right partition */ + if (d1 > es) { #ifdef I_AM_QSORT_R - qsort_r(a, r / es, es, thunk, cmp); + qsort_r(a, d1 / es, es, thunk, cmp); #else - qsort(a, r / es, es, cmp); + qsort(a, d1 / es, es, cmp); #endif - if ((r = pd - pc) > es) { - /* Iterate rather than recurse to save stack space */ - a = pn - r; - n = r / es; - goto loop; + } + if (d2 > es) { + /* Iterate rather than recurse to save stack space */ + /* qsort(pn - d2, d2 / es, es, cmp); */ + a = pn - d2; + n = d2 / es; + goto loop; + } + } else { + /* Recurse on right partition, then iterate on left partition */ + if (d2 > es) { +#ifdef I_AM_QSORT_R + qsort_r(pn - d2, d2 / es, es, thunk, cmp); +#else + qsort(pn - d2, d2 / es, es, cmp); +#endif + } + if (d1 > es) { + /* Iterate rather than recurse to save stack space */ + /* qsort(a, d1 / es, es, cmp); */ + n = d1 / es; + goto loop; + } } -/* qsort(pn - r, r / es, es, cmp);*/ } diff --git a/tests/Android.bp b/tests/Android.bp index a03f1a66e..1981457fd 100644 --- a/tests/Android.bp +++ b/tests/Android.bp @@ -88,6 +88,7 @@ cc_test_library { "nl_types_test.cpp", "pthread_test.cpp", "pty_test.cpp", + "qsort_test.cpp", "regex_test.cpp", "resolv_test.cpp", "sched_test.cpp", diff --git a/tests/qsort_test.cpp b/tests/qsort_test.cpp new file mode 100644 index 000000000..95b4789d8 --- /dev/null +++ b/tests/qsort_test.cpp @@ -0,0 +1,106 @@ +/* + * Copyright (C) 2017 The Android Open Source Project + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#include +#include + +#include + +#include "gtest_globals.h" + +#define BUFFER_SIZE 1024 + +static int cmp_long(const void *l, const void *r) +{ + + return (*(long *)l - *(long *)r); +} + +static int cmp_int(const void *l, const void *r) +{ + + return (*(int *)l - *(int *)r); +} + +#ifndef arc4random_uniform +static bool seeded; + +u_int32_t arc4random_uniform(uint32_t upper_bound) +{ + if (!seeded) { + srandom((int)time(NULL)); + seeded = true; + } + + return (random() % upper_bound); +} +#endif + +TEST(qsort_test, long_test) { + long buf[BUFFER_SIZE]; + long i; + + /* Initialize buffer with known numbers */ + for (i=0; i