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stdlib/psort.c.patch /dev/null Libc-763.13
--- /dev/null
+++ Libc/Libc-763.13/stdlib/psort.c.patch
@@ -0,0 +1,334 @@
+--- psort.c.orig	2008-11-24 17:01:07.000000000 -0800
++++ psort.c	2008-11-24 22:02:57.000000000 -0800
+@@ -1,3 +1,4 @@
++/****************************************************************************/
+ /*-
+  * Copyright (c) 1992, 1993
+  *	The Regents of the University of California.  All rights reserved.
+@@ -34,14 +35,22 @@ static char sccsid[] = "@(#)qsort.c	8.1 
+ __FBSDID("$FreeBSD: src/lib/libc/stdlib/qsort.c,v 1.15 2008/01/14 09:21:34 das Exp $");
+ 
+ #include <stdlib.h>
++#include <pthread.h>
++#include <dispatch/dispatch.h>
++#include <stddef.h>
+ #include <string.h>
++#include <libkern/OSAtomic.h>
++#include <sys/mman.h>
++#include <errno.h>
++#define __APPLE_API_PRIVATE
++#include <machine/cpu_capabilities.h>
+ 
+-#ifdef I_AM_QSORT_R
++#ifdef I_AM_PSORT_R
+ typedef int		 cmp_t(void *, const void *, const void *);
+ #else
+ typedef int		 cmp_t(const void *, const void *);
+ #endif
+-#ifdef I_AM_QSORT_B
++#ifdef I_AM_PSORT_B
+ static inline char	*med3(char *, char *, char *, cmp_t ^, void *) __attribute__((always_inline));
+ #else
+ static inline char	*med3(char *, char *, char *, cmp_t *, void *) __attribute__((always_inline));
+@@ -50,6 +59,83 @@ static inline void	 swapfunc(char *, cha
+ 
+ #define min(a, b)	(a) < (b) ? a : b
+ 
++#define NARGS			((PAGESIZE - offsetof(struct page, args)) / sizeof(union args))
++#define PAGESIZE		4096
++#define PARALLEL_MIN_SIZE	2000	/* determine heuristically */
++
++struct shared; /* forward reference */
++union args {
++    union args *next;
++    struct {
++	struct shared *shared;
++	void *a;
++	size_t n;
++	int depth_limit;
++    } /* anonymous */;
++};
++
++struct page {
++    struct page *next;
++    union args args[0];
++};
++
++struct shared {
++    char *who;
++    union args *freelist;
++    struct page *pagelist;
++#ifdef I_AM_PSORT_R
++    void *thunk;
++#endif
++#ifdef I_AM_PSORT_B
++    cmp_t ^cmp;
++#else
++    cmp_t *cmp;
++#endif
++    size_t es;
++    size_t turnoff;
++    dispatch_queue_t queue;
++    pthread_cond_t cond;
++    pthread_mutex_t mutex;
++    OSSpinLock sharedlock;
++    int count;
++};
++
++static union args *
++getargs(struct shared *shared)
++{
++    union args *args;
++
++    OSSpinLockLock(&shared->sharedlock);
++    if(!shared->freelist) {
++	struct page *page;
++	union args *prev;
++	int i;
++	if((page = (struct page *)mmap(NULL, PAGESIZE, PROT_READ|PROT_WRITE, MAP_ANON|MAP_PRIVATE, -1, 0)) == NULL)
++	    return NULL;
++	page->next = shared->pagelist;
++	shared->pagelist = page;
++	prev = NULL;
++	for(args = page->args, i = NARGS; i > 0; args++, i--) {
++	    args->next = prev;
++	    prev = args;
++	}
++	shared->freelist = prev;
++    }
++    args = shared->freelist;
++    shared->freelist = args->next;
++    OSSpinLockUnlock(&shared->sharedlock);
++    return args;
++}
++
++static void
++returnargs(struct shared *shared, union args *args)
++{
++    OSSpinLockLock(&shared->sharedlock);
++    args->next = shared->freelist;
++    shared->freelist = args;
++    OSSpinLockUnlock(&shared->sharedlock);
++}
++
+ /*
+  * Qsort routine from Bentley & McIlroy's "Engineering a Sort Function".
+  */
+@@ -88,7 +174,7 @@ swapfunc(a, b, n, swaptype)
+ 
+ #define vecswap(a, b, n) 	if ((n) > 0) swapfunc(a, b, n, swaptype)
+ 
+-#ifdef I_AM_QSORT_R
++#ifdef I_AM_PSORT_R
+ #define	CMP(t, x, y) (cmp((t), (x), (y)))
+ #else
+ #define	CMP(t, x, y) (cmp((x), (y)))
+@@ -96,13 +182,13 @@ swapfunc(a, b, n, swaptype)
+ 
+ static inline char *
+ med3(char *a, char *b, char *c,
+-#ifdef I_AM_QSORT_B
++#ifdef I_AM_PSORT_B
+ cmp_t ^cmp,
+ #else
+ cmp_t *cmp,
+ #endif
+ void *thunk
+-#ifndef I_AM_QSORT_R
++#ifndef I_AM_PSORT_R
+ __unused
+ #endif
+ )
+@@ -118,23 +204,25 @@ __unused
+ #define DEPTH(x)	(2 * (fls((int)(x)) - 1))
+ #endif /* __LP64__ */
+ 
+-#ifdef I_AM_QSORT_R
++#ifdef I_AM_PSORT_R
+ int __heapsort_r(void *, size_t, size_t, void *, int (*)(void *, const void *, const void *));
+ #endif
+ 
++static void _psort_parallel(void *x);
++
+ static void
+-_qsort(void *a, size_t n, size_t es,
+-#ifdef I_AM_QSORT_R
++_psort(void *a, size_t n, size_t es,
++#ifdef I_AM_PSORT_R
+ void *thunk,
+ #else
+ #define thunk	NULL
+ #endif
+-#ifdef I_AM_QSORT_B
++#ifdef I_AM_PSORT_B
+ cmp_t ^cmp,
+ #else
+ cmp_t *cmp,
+ #endif
+-int depth_limit)
++int depth_limit, struct shared *shared)
+ {
+ 	char *pa, *pb, *pc, *pd, *pl, *pm, *pn;
+ 	size_t d, r;
+@@ -143,9 +231,9 @@ int depth_limit)
+ 
+ loop:
+ 	if (depth_limit-- <= 0) {
+-#ifdef I_AM_QSORT_B
++#ifdef I_AM_PSORT_B
+ 		heapsort_b(a, n, es, cmp);
+-#elif defined(I_AM_QSORT_R)
++#elif defined(I_AM_PSORT_R)
+ 		__heapsort_r(a, n, es, thunk, cmp);
+ #else
+ 		heapsort(a, n, es, cmp);
+@@ -222,33 +310,135 @@ loop:
+ 	}
+ 
+ nevermind:
+-	if ((r = pb - pa) > es)
+-#ifdef I_AM_QSORT_R
+-		_qsort(a, r / es, es, thunk, cmp, depth_limit);
++	if ((r = pb - pa) > es) {
++		r /= es;
++		if (shared && r > shared->turnoff) {
++			union args *args = getargs(shared);
++
++			if (args == NULL)
++				LIBC_ABORT("%s: getargs: %s", shared->who, strerror(errno));
++			args->shared = shared;
++			args->a = a;
++			args->n = r;
++			args->depth_limit = depth_limit;
++			OSAtomicIncrement32(&shared->count);
++			dispatch_async_f(shared->queue, args, _psort_parallel);
++		} else {
++#ifdef I_AM_PSORT_R
++			_psort(a, r, es, thunk, cmp, depth_limit, NULL);
+ #else
+-		_qsort(a, r / es, es, cmp, depth_limit);
++			_psort(a, r, es, cmp, depth_limit, NULL);
+ #endif
++		}
++	}
+ 	if ((r = pd - pc) > es) {
+ 		/* Iterate rather than recurse to save stack space */
+ 		a = pn - r;
+ 		n = r / es;
+ 		goto loop;
+ 	}
+-/*		qsort(pn - r, r / es, es, cmp);*/
++/*		psort(pn - r, r / es, es, cmp);*/
++}
++
++static void
++_psort_parallel(void *x)
++{
++	union args *args = (union args *)x;
++	struct shared *shared = args->shared;
++
++	_psort(args->a, args->n, shared->es,
++#ifdef I_AM_PSORT_R
++		shared->thunk,
++#endif
++		shared->cmp, args->depth_limit, shared);
++	returnargs(shared, args);
++	if(OSAtomicDecrement32(&shared->count) <= 0) {
++		pthread_mutex_lock(&shared->mutex);
++		pthread_cond_signal(&shared->cond);
++		pthread_mutex_unlock(&shared->mutex);
++	}
++}
++
++/* fast, approximate integer square root */
++static size_t
++isqrt(size_t x)
++{
++    size_t s = 1L << (flsl(x) / 2);
++    return (s + x / s) / 2;
+ }
+ 
+ void
+-#ifdef I_AM_QSORT_R
+-qsort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp)
+-#elif defined(I_AM_QSORT_B)
+-qsort_b(void *a, size_t n, size_t es, cmp_t ^cmp)
++#ifdef I_AM_PSORT_R
++psort_r(void *a, size_t n, size_t es, void *thunk, cmp_t *cmp)
++#elif defined(I_AM_PSORT_B)
++psort_b(void *a, size_t n, size_t es, cmp_t ^cmp)
+ #else
+-qsort(void *a, size_t n, size_t es, cmp_t *cmp)
++psort(void *a, size_t n, size_t es, cmp_t *cmp)
+ #endif
+ {
+-	_qsort(a, n, es,
+-#ifdef I_AM_QSORT_R
+-		thunk,
++	if (n >= PARALLEL_MIN_SIZE && _NumCPUs() > 1) {
++		struct shared shared;
++		union args *args;
++
++		bzero(&shared, sizeof(shared));
++		shared.sharedlock = OS_SPINLOCK_INIT;
++		if ((args = getargs(&shared)) != NULL) {
++			struct page *p, *pp;
++#ifdef I_AM_PSORT_R
++			shared.who = "psort_r";
++			shared.thunk = thunk;
++#elif defined(I_AM_PSORT_B)
++			shared.who = "psort_b";
++#else
++			shared.who = "psort";
++#endif
++			shared.cmp = cmp;
++			shared.es = es;
++			shared.queue = dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0);
++			shared.cond = (pthread_cond_t)PTHREAD_COND_INITIALIZER;
++			shared.mutex = (pthread_mutex_t)PTHREAD_MUTEX_INITIALIZER;
++			args->a = a;
++			args->n = n;
++			args->depth_limit = DEPTH(n);
++			args->shared = &shared;
++			/*
++			 * The turnoff value is the size of a partition that,
++			 * below which, we stop doing in parallel, and just do
++			 * in the current thread.  The value of sqrt(n) was
++			 * determined heuristically.  There is a smaller
++			 * dependence on the slowness of the comparison
++			 * function, and there might be a dependence on the
++			 * number of processors, but the algorithm has not been
++			 * determined.  Because the sensitivity to the turnoff
++			 * value is relatively low, we use a fast, approximate
++			 * integer square root routine that is good enough for
++			 * this purpose.
++			 */
++			shared.turnoff = isqrt(n);
++			OSAtomicIncrement32(&shared.count);
++			_psort_parallel(args);
++
++			/* wait for queue to drain */
++			pthread_mutex_lock(&shared.mutex);
++			while(shared.count > 0)
++				pthread_cond_wait(&shared.cond, &shared.mutex);
++
++			pthread_mutex_unlock(&shared.mutex);
++			pthread_mutex_destroy(&shared.mutex);
++			pthread_cond_destroy(&shared.cond);
++			for(p = shared.pagelist; p; p = pp) {
++				pp = p->next;
++				munmap(p, PAGESIZE);
++			}
++			return;
++		}
++	}
++	/* Just call qsort */
++#ifdef I_AM_PSORT_R
++	qsort_r(a, n, es, thunk, cmp);
++#elif defined(I_AM_PSORT_B)
++	qsort_b(a, n, es, cmp);
++#else
++	qsort(a, n, es, cmp);
+ #endif
+-		cmp, DEPTH(n));
+ }