/* Sparse Arrays for Objective C dispatch tables
Copyright (C) 1993 Free Software Foundation, Inc.
Author: Kresten Krab Thorup
This file is part of GNU CC.
GNU CC is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2, or (at your option)
GNU CC 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with GNU CC; see the file COPYING. If not, write to
the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
/* As a special exception, if you link this library with files
compiled with GCC to produce an executable, this does not cause
the resulting executable to be covered by the GNU General Public License.
This exception does not however invalidate any other reasons why
the executable file might be covered by the GNU General Public License. */
#ifndef __sarray_INCLUDE_GNU
#define __sarray_INCLUDE_GNU
#define OBJC_SPARSE2 /* 2-level sparse array */
/* #define OBJC_SPARSE3 */ /* 3-level sparse array */
extern const char* __objc_sparse2_id
;
extern const char* __objc_sparse3_id
;
extern int nbuckets
; /* for stats */
/* An unsigned integer of same size as a pointer */
#define SIZET_BITS (sizeof(size_t)*8)
#if defined(sparc) || defined(OBJC_SPARSE2)
#define PRECOMPUTE_SELECTORS
/* Buckets are 8 words each */
#define BUCKET_SIZE (1<<BUCKET_BITS)
#define BUCKET_MASK (BUCKET_SIZE-1)
/* Indices are 16 words each */
#define INDEX_SIZE (1<<INDEX_BITS)
#define INDEX_MASK (INDEX_SIZE-1)
#define INDEX_CAPACITY (BUCKET_SIZE*INDEX_SIZE)
/* Buckets are 32 words each */
#define BUCKET_SIZE (1<<BUCKET_BITS)
#define BUCKET_MASK (BUCKET_SIZE-1)
#endif /* OBJC_SPARSE2 */
#ifdef PRECOMPUTE_SELECTORS
unsigned int unused
: SIZET_BITS
/4;
unsigned int eoffset
: SIZET_BITS
/4;
unsigned int boffset
: SIZET_BITS
/4;
unsigned int ioffset
: SIZET_BITS
/4;
unsigned int boffset
: (SIZET_BITS
- 2) - BUCKET_BITS
;
unsigned int eoffset
: BUCKET_BITS
;
unsigned int boffset
: SIZET_BITS
/2;
unsigned int eoffset
: SIZET_BITS
/2;
#endif /* OBJC_SPARSE2 */
#endif /* not PRECOMPUTE_SELECTORS */
void * __objc_xrealloc (void *optr
, size_t size
);
void * __objc_xmalloc (size_t size
);
void* elems
[BUCKET_SIZE
]; /* elements stored in array */
short version
; /* used for copy-on-write */
struct sbucket
* buckets
[INDEX_SIZE
];
#endif /* OBJC_SPARSE3 */
struct sindex
* empty_index
;
struct sbucket
** buckets
;
#endif /* OBJC_SPARSE2 */
struct sbucket
* empty_bucket
;
struct sarray
* is_copy_of
;
struct sarray
* sarray_new(int, void* default_element
);
void sarray_free(struct sarray
*);
struct sarray
* sarray_lazy_copy(struct sarray
*);
struct sarray
* sarray_hard_copy(struct sarray
*); /* ... like the name? */
void sarray_realloc(struct sarray
*, int new_size
);
void sarray_at_put(struct sarray
*, sidx index
, void* elem
);
void sarray_at_put_safe(struct sarray
*, sidx index
, void* elem
);
#ifdef PRECOMPUTE_SELECTORS
/* Transform soffset values to ints and vica verca */
static inline unsigned int
soffset_decode(sidx index
)
+ (x
.off
.boffset
*BUCKET_SIZE
)
+ (x
.off
.ioffset
*INDEX_CAPACITY
);
return x
.off
.eoffset
+ (x
.off
.boffset
*BUCKET_SIZE
);
#endif /* OBJC_SPARSE2 */
soffset_encode(size_t offset
)
x
.off
.eoffset
= offset
%BUCKET_SIZE
;
x
.off
.boffset
= (offset
/BUCKET_SIZE
)%INDEX_SIZE
;
x
.off
.ioffset
= offset
/INDEX_CAPACITY
;
x
.off
.boffset
= offset
/BUCKET_SIZE
;
#else /* not PRECOMPUTE_SELECTORS */
soffset_decode(sidx index
)
soffset_encode(size_t offset
)
#endif /* not PRECOMPUTE_SELECTORS */
/* Get element from the Sparse array `array' at offset `index' */
static inline void* sarray_get(struct sarray
* array
, sidx index
)
#ifdef PRECOMPUTE_SELECTORS
return array
->buckets
[x
.off
.boffset
]->elems
[x
.off
.eoffset
];
#endif /* OBJC_SPARSE2 */
#else /* not PRECOMPUTE_SELECTORS */
indices
[index
/INDEX_CAPACITY
]->
buckets
[(index
/BUCKET_SIZE
)%INDEX_SIZE
]->
elems
[index
%BUCKET_SIZE
];
return array
->buckets
[index
/BUCKET_SIZE
]->elems
[index
%BUCKET_SIZE
];
#endif /* not OBJC_SPARSE3 */
#endif /* not PRECOMPUTE_SELECTORS */
static inline void* sarray_get_safe(struct sarray
* array
, sidx index
)
if(soffset_decode(index
) < array
->capacity
)
return sarray_get(array
, index
);
return (array
->empty_bucket
->elems
[0]);
#endif /* __sarray_INCLUDE_GNU */