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author | delphij <delphij@FreeBSD.org> | 2017-05-31 06:13:33 +0000 |
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committer | delphij <delphij@FreeBSD.org> | 2017-05-31 06:13:33 +0000 |
commit | 6c25a3b3001c6d7f3751728cc02f53f98010348f (patch) | |
tree | 0ff915d7b41d0cbf3d4da69bc92aef0834e78536 /lib | |
parent | 1a5f55018b250a8e6a152f97a4e497e2e13fb12f (diff) | |
download | FreeBSD-src-6c25a3b3001c6d7f3751728cc02f53f98010348f.zip FreeBSD-src-6c25a3b3001c6d7f3751728cc02f53f98010348f.tar.gz |
MFC r279663,r279666 (pfg):
r279663:
qsort(3): enhance to handle 32-bit aligned data on 64-bit systems
Implement a small enhancement to the original qsort implementation:
If the data is 32 bit aligned we can side-step the long type
version and use int instead.
The change brings a modest but significant improvement in
32 bit workloads.
r279666:
qsort(3): small style(9) cleanups.
Basically spaces vs. tabs.
No functional change.
Diffstat (limited to 'lib')
-rw-r--r-- | lib/libc/stdlib/qsort.c | 53 |
1 files changed, 31 insertions, 22 deletions
diff --git a/lib/libc/stdlib/qsort.c b/lib/libc/stdlib/qsort.c index 93e22cd..e97ea92 100644 --- a/lib/libc/stdlib/qsort.c +++ b/lib/libc/stdlib/qsort.c @@ -41,47 +41,55 @@ 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 *, int, 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) { \ + long 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) +swapfunc(a, b, n, swaptype_long, swaptype_int) char *a, *b; - int n, swaptype; + int n, swaptype_long, 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))) @@ -98,14 +106,14 @@ __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 @@ -113,9 +121,10 @@ qsort(void *a, size_t n, size_t es, cmp_t *cmp) char *pa, *pb, *pc, *pd, *pl, *pm, *pn; size_t d, r; 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) @@ -175,9 +184,9 @@ loop: SWAPINIT(a, es); } pn = (char *)a + n * es; - r = min(pa - (char *)a, pb - pa); + r = MIN(pa - (char *)a, pb - pa); vecswap(a, pb - r, r); - r = min(pd - pc, pn - pd - es); + r = MIN(pd - pc, pn - pd - es); vecswap(pb, pn - r, r); if ((r = pb - pa) > es) #ifdef I_AM_QSORT_R |