SDL  2.0
SDL_qsort.c File Reference
#include "../SDL_internal.h"
#include "SDL_stdinc.h"
#include "SDL_assert.h"
+ Include dependency graph for SDL_qsort.c:

Go to the source code of this file.

Data Structures

struct  stack_entry
 

Macros

#define assert(X)   SDL_assert(X)
 
#define malloc   SDL_malloc
 
#define free   SDL_free
 
#define memcpy   SDL_memcpy
 
#define memmove   SDL_memmove
 
#define qsort   SDL_qsort
 
#define WORD_BYTES   sizeof(int)
 
#define STACK_SIZE   (8*sizeof(size_t))
 
#define TRUNC_nonaligned   12
 
#define TRUNC_aligned   12
 
#define TRUNC_words   12*WORD_BYTES /* nb different meaning */
 
#define PIVOT_THRESHOLD   40
 
#define pushLeft   {stack[stacktop].first=ffirst;stack[stacktop++].last=last;}
 
#define pushRight   {stack[stacktop].first=first;stack[stacktop++].last=llast;}
 
#define doLeft   {first=ffirst;llast=last;continue;}
 
#define doRight   {ffirst=first;last=llast;continue;}
 
#define pop
 
#define Recurse(Trunc)
 
#define Pivot(swapper, sz)
 
#define Partition(swapper, sz)
 
#define PreInsertion(swapper, limit, sz)
 
#define Insertion(swapper)
 
#define SWAP_nonaligned(a, b)
 
#define SWAP_aligned(a, b)
 
#define SWAP_words(a, b)
 

Functions

static char * pivot_big (char *first, char *mid, char *last, size_t size, int compare(const void *, const void *))
 
static void qsort_nonaligned (void *base, size_t nmemb, size_t size, int(*compare)(const void *, const void *))
 
static void qsort_aligned (void *base, size_t nmemb, size_t size, int(*compare)(const void *, const void *))
 
static void qsort_words (void *base, size_t nmemb, int(*compare)(const void *, const void *))
 
void qsort (void *base, size_t nmemb, size_t size, int(*compare)(const void *, const void *))
 

Variables

static const char _ID [] = "<qsort.c gjm 1.12 1998-03-19>"
 

Macro Definition Documentation

#define assert (   X)    SDL_assert(X)

Definition at line 70 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define doLeft   {first=ffirst;llast=last;continue;}

Definition at line 128 of file SDL_qsort.c.

#define doRight   {ffirst=first;last=llast;continue;}

Definition at line 129 of file SDL_qsort.c.

#define free   SDL_free

Definition at line 78 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define Insertion (   swapper)
Value:
last=((char*)base)+nmemb*size; \
for (first=((char*)base)+size;first!=last;first+=size) { \
char *test; \
/* Find the right place for |first|. \
* My apologies for var reuse. */ \
for (test=first-size;compare(test,first)>0;test-=size) ; \
test+=size; \
if (test!=first) { \
/* Shift everything in [test,first) \
* up by one, and place |first| \
* where |test| is. */ \
memmove(test+size,test,first-test); \
memcpy(test,pivot,size); \
} \
}
const GLint * first
#define memcpy
Definition: SDL_qsort.c:82
#define memmove
Definition: SDL_qsort.c:86
GLsizeiptr size

Definition at line 264 of file SDL_qsort.c.

Referenced by qsort_aligned(), and qsort_nonaligned().

#define malloc   SDL_malloc

Definition at line 74 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define memcpy   SDL_memcpy

Definition at line 82 of file SDL_qsort.c.

Referenced by qsort_aligned(), and qsort_nonaligned().

#define memmove   SDL_memmove

Definition at line 86 of file SDL_qsort.c.

Referenced by SDL_memmove().

#define Partition (   swapper,
  sz 
)
Value:
{ \
int swapped=0; \
do { \
while (compare(first,pivot)<0) first+=sz; \
while (compare(pivot,last)<0) last-=sz; \
if (first<last) { \
swapper(first,last); swapped=1; \
first+=sz; last-=sz; } \
else if (first==last) { first+=sz; last-=sz; break; }\
} while (first<=last); \
if (!swapped) pop \
}
const GLint * first
#define pop
Definition: SDL_qsort.c:130

Definition at line 237 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define Pivot (   swapper,
  sz 
)
Value:
if ((size_t)(last-first)>PIVOT_THRESHOLD*sz) mid=pivot_big(first,mid,last,sz,compare);\
else { \
if (compare(first,mid)<0) { \
if (compare(mid,last)>0) { \
swapper(mid,last); \
if (compare(first,mid)>0) swapper(first,mid);\
} \
} \
else { \
if (compare(mid,last)>0) swapper(first,last)\
else { \
swapper(first,mid); \
if (compare(mid,last)>0) swapper(mid,last);\
} \
} \
first+=sz; last-=sz; \
}
const GLint * first
static char * pivot_big(char *first, char *mid, char *last, size_t size, int compare(const void *, const void *))
Definition: SDL_qsort.c:298
#define PIVOT_THRESHOLD
Definition: SDL_qsort.c:119

Definition at line 213 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define PIVOT_THRESHOLD   40

Definition at line 119 of file SDL_qsort.c.

#define pop
Value:
{if (--stacktop<0) break;\
first=ffirst=stack[stacktop].first;\
last=llast=stack[stacktop].last;\
continue;}
const GLint * first

Definition at line 130 of file SDL_qsort.c.

Referenced by CPU_haveCPUID(), SDL_SoftStretch(), and SDL_tolower().

#define PreInsertion (   swapper,
  limit,
  sz 
)
Value:
first=base; \
last=first + (nmemb>limit ? limit : nmemb-1)*sz;\
while (last!=base) { \
if (compare(first,last)>0) first=last; \
last-=sz; } \
if (first!=base) swapper(first,(char*)base);
GLint limit
const GLint * first

Definition at line 255 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define pushLeft   {stack[stacktop].first=ffirst;stack[stacktop++].last=last;}

Definition at line 126 of file SDL_qsort.c.

#define pushRight   {stack[stacktop].first=first;stack[stacktop++].last=llast;}

Definition at line 127 of file SDL_qsort.c.

#define qsort   SDL_qsort

Definition at line 90 of file SDL_qsort.c.

#define Recurse (   Trunc)
Value:
{ size_t l=last-ffirst,r=llast-first; \
if (l<Trunc) { \
if (r>=Trunc) doRight \
else pop \
} \
else if (l<=r) { pushLeft; doRight } \
else if (r>=Trunc) { pushRight; doLeft }\
else doLeft \
}
#define pushRight
Definition: SDL_qsort.c:127
GLdouble GLdouble GLdouble r
Definition: SDL_opengl.h:2072
const GLint * first
#define pop
Definition: SDL_qsort.c:130
#define doRight
Definition: SDL_qsort.c:129
#define doLeft
Definition: SDL_qsort.c:128
#define pushLeft
Definition: SDL_qsort.c:126

Definition at line 201 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define STACK_SIZE   (8*sizeof(size_t))

Definition at line 102 of file SDL_qsort.c.

Referenced by qsort_aligned(), qsort_nonaligned(), and qsort_words().

#define SWAP_aligned (   a,
  b 
)
Value:
{ \
register int *aa=(int*)(a),*bb=(int*)(b); \
register size_t sz=size; \
do { register int t=*aa;*aa++=*bb; *bb++=t; } while (sz-=WORD_BYTES); }
#define WORD_BYTES
Definition: SDL_qsort.c:97
GLsizeiptr size
GLdouble GLdouble t
Definition: SDL_opengl.h:2064
GLboolean GLboolean GLboolean GLboolean a
GLboolean GLboolean GLboolean b

Definition at line 287 of file SDL_qsort.c.

Referenced by qsort_aligned().

#define SWAP_nonaligned (   a,
  b 
)
Value:
{ \
register char *aa=(a),*bb=(b); \
register size_t sz=size; \
do { register char t=*aa; *aa++=*bb; *bb++=t; } while (--sz); }
GLsizeiptr size
GLdouble GLdouble t
Definition: SDL_opengl.h:2064
GLboolean GLboolean GLboolean GLboolean a
GLboolean GLboolean GLboolean b

Definition at line 282 of file SDL_qsort.c.

Referenced by qsort_nonaligned().

#define SWAP_words (   a,
  b 
)
Value:
{ \
register int t=*((int*)a); *((int*)a)=*((int*)b); *((int*)b)=t; }
GLdouble GLdouble t
Definition: SDL_opengl.h:2064
GLboolean GLboolean GLboolean GLboolean a
GLboolean GLboolean GLboolean b

Definition at line 292 of file SDL_qsort.c.

Referenced by qsort_words().

#define TRUNC_aligned   12

Definition at line 112 of file SDL_qsort.c.

Referenced by qsort_aligned().

#define TRUNC_nonaligned   12

Definition at line 111 of file SDL_qsort.c.

Referenced by qsort_nonaligned().

#define TRUNC_words   12*WORD_BYTES /* nb different meaning */

Definition at line 113 of file SDL_qsort.c.

Referenced by qsort_words().

#define WORD_BYTES   sizeof(int)

Definition at line 97 of file SDL_qsort.c.

Referenced by qsort(), and qsort_words().

Function Documentation

static char* pivot_big ( char *  first,
char *  mid,
char *  last,
size_t  size,
int   compareconst void *, const void * 
)
static

Definition at line 298 of file SDL_qsort.c.

References d.

300 {
301  size_t d = (((last - first) / size) >> 3) * size;
302  char *m1, *m2, *m3;
303  {
304  char *a = first, *b = first + d, *c = first + 2 * d;
305 #ifdef DEBUG_QSORT
306  fprintf(stderr, "< %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
307 #endif
308  m1 = compare(a, b) < 0 ?
309  (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
310  : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
311  }
312  {
313  char *a = mid - d, *b = mid, *c = mid + d;
314 #ifdef DEBUG_QSORT
315  fprintf(stderr, ". %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
316 #endif
317  m2 = compare(a, b) < 0 ?
318  (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
319  : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
320  }
321  {
322  char *a = last - 2 * d, *b = last - d, *c = last;
323 #ifdef DEBUG_QSORT
324  fprintf(stderr, "> %d %d %d\n", *(int *) a, *(int *) b, *(int *) c);
325 #endif
326  m3 = compare(a, b) < 0 ?
327  (compare(b, c) < 0 ? b : (compare(a, c) < 0 ? c : a))
328  : (compare(a, c) < 0 ? a : (compare(b, c) < 0 ? c : b));
329  }
330 #ifdef DEBUG_QSORT
331  fprintf(stderr, "-> %d %d %d\n", *(int *) m1, *(int *) m2, *(int *) m3);
332 #endif
333  return compare(m1, m2) < 0 ?
334  (compare(m2, m3) < 0 ? m2 : (compare(m1, m3) < 0 ? m3 : m1))
335  : (compare(m1, m3) < 0 ? m1 : (compare(m2, m3) < 0 ? m3 : m2));
336 }
const GLint * first
GLsizeiptr size
SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char int SDL_PRINTF_FORMAT_STRING const char const char SDL_SCANF_FORMAT_STRING const char return SDL_ThreadFunction const char void return Uint32 return Uint32 SDL_AssertionHandler void SDL_SpinLock SDL_atomic_t int int return SDL_atomic_t return void void void return void return int return SDL_AudioSpec SDL_AudioSpec return int int return return int SDL_RWops int SDL_AudioSpec Uint8 ** d
const GLubyte * c
GLboolean GLboolean GLboolean GLboolean a
GLboolean GLboolean GLboolean b
void qsort ( void base,
size_t  nmemb,
size_t  size,
int(*)(const void *, const void *)  compare 
)

Definition at line 465 of file SDL_qsort.c.

References qsort_aligned(), qsort_nonaligned(), qsort_words(), and WORD_BYTES.

467 {
468 
469  if (nmemb <= 1)
470  return;
471  if (((uintptr_t) base | size) & (WORD_BYTES - 1))
472  qsort_nonaligned(base, nmemb, size, compare);
473  else if (size != WORD_BYTES)
474  qsort_aligned(base, nmemb, size, compare);
475  else
476  qsort_words(base, nmemb, compare);
477 }
#define WORD_BYTES
Definition: SDL_qsort.c:97
GLsizeiptr size
static void qsort_nonaligned(void *base, size_t nmemb, size_t size, int(*compare)(const void *, const void *))
Definition: SDL_qsort.c:341
unsigned int uintptr_t
static void qsort_words(void *base, size_t nmemb, int(*compare)(const void *, const void *))
Definition: SDL_qsort.c:409
static void qsort_aligned(void *base, size_t nmemb, size_t size, int(*compare)(const void *, const void *))
Definition: SDL_qsort.c:375
static void qsort_aligned ( void base,
size_t  nmemb,
size_t  size,
int(*)(const void *, const void *)  compare 
)
static

Definition at line 375 of file SDL_qsort.c.

References assert, free, Insertion, malloc, memcpy, Partition, Pivot, PreInsertion, Recurse, STACK_SIZE, SWAP_aligned, and TRUNC_aligned.

Referenced by qsort().

377 {
378 
379  stack_entry stack[STACK_SIZE];
380  int stacktop = 0;
381  char *first, *last;
382  char *pivot = malloc(size);
383  size_t trunc = TRUNC_aligned * size;
384  assert(pivot != 0);
385 
386  first = (char *) base;
387  last = first + (nmemb - 1) * size;
388 
389  if ((size_t) (last - first) > trunc) {
390  char *ffirst = first, *llast = last;
391  while (1) {
392  /* Select pivot */
393  {
394  char *mid = first + size * ((last - first) / size >> 1);
395  Pivot(SWAP_aligned, size);
396  memcpy(pivot, mid, size);
397  }
398  /* Partition. */
399  Partition(SWAP_aligned, size);
400  /* Prepare to recurse/iterate. */
401  Recurse(trunc)}
402  }
405  free(pivot);
406 }
#define SWAP_aligned(a, b)
Definition: SDL_qsort.c:287
#define TRUNC_aligned
Definition: SDL_qsort.c:112
Definition: SDL_qsort.c:121
const GLint * first
#define PreInsertion(swapper, limit, sz)
Definition: SDL_qsort.c:255
#define memcpy
Definition: SDL_qsort.c:82
#define Pivot(swapper, sz)
Definition: SDL_qsort.c:213
GLsizeiptr size
#define STACK_SIZE
Definition: SDL_qsort.c:102
#define Recurse(Trunc)
Definition: SDL_qsort.c:201
#define assert(X)
Definition: SDL_qsort.c:70
#define Insertion(swapper)
Definition: SDL_qsort.c:264
#define free
Definition: SDL_qsort.c:78
#define Partition(swapper, sz)
Definition: SDL_qsort.c:237
#define malloc
Definition: SDL_qsort.c:74
static void qsort_nonaligned ( void base,
size_t  nmemb,
size_t  size,
int(*)(const void *, const void *)  compare 
)
static

Definition at line 341 of file SDL_qsort.c.

References assert, free, Insertion, malloc, memcpy, Partition, Pivot, PreInsertion, Recurse, STACK_SIZE, SWAP_nonaligned, and TRUNC_nonaligned.

Referenced by qsort().

343 {
344 
345  stack_entry stack[STACK_SIZE];
346  int stacktop = 0;
347  char *first, *last;
348  char *pivot = malloc(size);
349  size_t trunc = TRUNC_nonaligned * size;
350  assert(pivot != 0);
351 
352  first = (char *) base;
353  last = first + (nmemb - 1) * size;
354 
355  if ((size_t) (last - first) > trunc) {
356  char *ffirst = first, *llast = last;
357  while (1) {
358  /* Select pivot */
359  {
360  char *mid = first + size * ((last - first) / size >> 1);
361  Pivot(SWAP_nonaligned, size);
362  memcpy(pivot, mid, size);
363  }
364  /* Partition. */
365  Partition(SWAP_nonaligned, size);
366  /* Prepare to recurse/iterate. */
367  Recurse(trunc)}
368  }
371  free(pivot);
372 }
Definition: SDL_qsort.c:121
const GLint * first
#define PreInsertion(swapper, limit, sz)
Definition: SDL_qsort.c:255
#define memcpy
Definition: SDL_qsort.c:82
#define Pivot(swapper, sz)
Definition: SDL_qsort.c:213
GLsizeiptr size
#define STACK_SIZE
Definition: SDL_qsort.c:102
#define Recurse(Trunc)
Definition: SDL_qsort.c:201
#define TRUNC_nonaligned
Definition: SDL_qsort.c:111
#define assert(X)
Definition: SDL_qsort.c:70
#define SWAP_nonaligned(a, b)
Definition: SDL_qsort.c:282
#define Insertion(swapper)
Definition: SDL_qsort.c:264
#define free
Definition: SDL_qsort.c:78
#define Partition(swapper, sz)
Definition: SDL_qsort.c:237
#define malloc
Definition: SDL_qsort.c:74
static void qsort_words ( void base,
size_t  nmemb,
int(*)(const void *, const void *)  compare 
)
static

Definition at line 409 of file SDL_qsort.c.

References assert, free, malloc, Partition, Pivot, PreInsertion, Recurse, STACK_SIZE, SWAP_words, TRUNC_words, and WORD_BYTES.

Referenced by qsort().

411 {
412 
413  stack_entry stack[STACK_SIZE];
414  int stacktop = 0;
415  char *first, *last;
416  char *pivot = malloc(WORD_BYTES);
417  assert(pivot != 0);
418 
419  first = (char *) base;
420  last = first + (nmemb - 1) * WORD_BYTES;
421 
422  if (last - first > TRUNC_words) {
423  char *ffirst = first, *llast = last;
424  while (1) {
425 #ifdef DEBUG_QSORT
426  fprintf(stderr, "Doing %d:%d: ",
427  (first - (char *) base) / WORD_BYTES,
428  (last - (char *) base) / WORD_BYTES);
429 #endif
430  /* Select pivot */
431  {
432  char *mid =
433  first + WORD_BYTES * ((last - first) / (2 * WORD_BYTES));
435  *(int *) pivot = *(int *) mid;
436  }
437 #ifdef DEBUG_QSORT
438  fprintf(stderr, "pivot=%d\n", *(int *) pivot);
439 #endif
440  /* Partition. */
442  /* Prepare to recurse/iterate. */
444  }
446  /* Now do insertion sort. */
447  last = ((char *) base) + nmemb * WORD_BYTES;
448  for (first = ((char *) base) + WORD_BYTES; first != last;
449  first += WORD_BYTES) {
450  /* Find the right place for |first|. My apologies for var reuse */
451  int *pl = (int *) (first - WORD_BYTES), *pr = (int *) first;
452  *(int *) pivot = *(int *) first;
453  for (; compare(pl, pivot) > 0; pr = pl, --pl) {
454  *pr = *pl;
455  }
456  if (pr != (int *) first)
457  *pr = *(int *) pivot;
458  }
459  free(pivot);
460 }
#define WORD_BYTES
Definition: SDL_qsort.c:97
Definition: SDL_qsort.c:121
const GLint * first
#define PreInsertion(swapper, limit, sz)
Definition: SDL_qsort.c:255
#define Pivot(swapper, sz)
Definition: SDL_qsort.c:213
#define SWAP_words(a, b)
Definition: SDL_qsort.c:292
#define STACK_SIZE
Definition: SDL_qsort.c:102
#define Recurse(Trunc)
Definition: SDL_qsort.c:201
#define assert(X)
Definition: SDL_qsort.c:70
#define TRUNC_words
Definition: SDL_qsort.c:113
#define free
Definition: SDL_qsort.c:78
#define Partition(swapper, sz)
Definition: SDL_qsort.c:237
#define malloc
Definition: SDL_qsort.c:74

Variable Documentation

const char _ID[] = "<qsort.c gjm 1.12 1998-03-19>"
static

Definition at line 92 of file SDL_qsort.c.