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riscv-gcc-1
Commit 1ebb5fcc by Richard Kenner
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(sarray_{remove,free}_garbage): New functions. 

(sarray_at_put, sarray_new, sarray_lazy_copy):
Modify/copy sarray structure/data in a thread-safe manner
(sarray_{realloc,free}): Reallocate/free sarray structure/data in a
thread-safe manner.

From-SVN: r11445
parent 54d643f6
Showing with 202 additions and 121 deletions
gcc/objc/sarray.c
/* Sparse Arrays for Objective C dispatch tables
Copyright (C) 1993, 1995 Free Software Foundation, Inc.
Copyright (C) 1993, 1995, 1996 Free Software Foundation, Inc.
This file is part of GNU CC.
......@@ -25,13 +25,16 @@ Boston, MA 02111-1307, USA. */
the executable file might be covered by the GNU General Public License. */
#include "objc/sarray.h"
#include "objc/runtime.h"
#include <stdio.h>
#include "assert.h"
int nbuckets = 0;
int nindices = 0;
int narrays = 0;
int idxsize = 0;
int nbuckets = 0; /* !T:MUTEX */
int nindices = 0; /* !T:MUTEX */
int narrays = 0; /* !T:MUTEX */
int idxsize = 0; /* !T:MUTEX */
static void * first_free_data = NULL; /* !T:MUTEX */
#ifdef OBJC_SPARSE2
const char* __objc_sparse2_id = "2 level sparse indices";
......@@ -46,13 +49,60 @@ const void *memcpy (void*, const void*, size_t);
void free (const void*);
#endif
/* This function removes any structures left over from free operations
that were not safe in a multi-threaded environment. */
void
sarray_remove_garbage(void)
{
void **vp;
void *np;
objc_mutex_lock(__objc_runtime_mutex);
vp = first_free_data;
first_free_data = NULL;
while (vp) {
np = *vp;
free(vp);
vp = np;
}
objc_mutex_unlock(__objc_runtime_mutex);
}
/* Free a block of dynamically allocated memory. If we are in multi-threaded
mode, it is ok to free it. If not, we add it to the garbage heap to be
freed later. */
static void
sarray_free_garbage(void *vp)
{
objc_mutex_lock(__objc_runtime_mutex);
if (__objc_runtime_threads_alive == 1) {
free(vp);
if (first_free_data)
sarray_remove_garbage();
}
else {
*(void **)vp = first_free_data;
first_free_data = vp;
}
objc_mutex_unlock(__objc_runtime_mutex);
}
/* sarray_at_put : copies data in such a way as to be thread reader safe. */
void
sarray_at_put(struct sarray* array, sidx index, void* element)
{
#ifdef OBJC_SPARSE3
struct sindex** the_index;
struct sindex* new_index;
#endif
struct sbucket** the_bucket;
struct sbucket* new_bucket;
#ifdef OBJC_SPARSE3
size_t ioffset;
#endif
......@@ -96,22 +146,24 @@ sarray_at_put(struct sarray* array, sidx index, void* element)
if ((*the_index) == array->empty_index) {
/* The index was previously empty, allocate a new */
*the_index = (struct sindex*)__objc_xmalloc(sizeof(struct sindex));
memcpy(*the_index, array->empty_index, sizeof(struct sindex));
(*the_index)->version = array->version;
new_index = (struct sindex*)__objc_xmalloc(sizeof(struct sindex));
memcpy(new_index, array->empty_index, sizeof(struct sindex));
new_index->version.version = array->version.version;
*the_index = new_index; /* Prepared for install. */
the_bucket = &((*the_index)->buckets[boffset]);
nindices += 1;
} else if ((*the_index)->version != array->version) {
nindices += 1;
} else if ((*the_index)->version.version != array->version.version) {
/* This index must be lazy copied */
struct sindex* old_index = *the_index;
*the_index = (struct sindex*)__objc_xmalloc(sizeof(struct sindex));
memcpy( *the_index,old_index, sizeof(struct sindex));
(*the_index)->version = array->version;
new_index = (struct sindex*)__objc_xmalloc(sizeof(struct sindex));
memcpy( new_index, old_index, sizeof(struct sindex));
new_index->version.version = array->version.version;
*the_index = new_index; /* Prepared for install. */
the_bucket = &((*the_index)->buckets[boffset]);
nindices += 1;
nindices += 1;
}
#endif /* OBJC_SPARSE3 */
......@@ -122,18 +174,22 @@ sarray_at_put(struct sarray* array, sidx index, void* element)
/* The bucket was previously empty (or something like that), */
/* allocate a new. This is the effect of `lazy' allocation */
*the_bucket = (struct sbucket*)__objc_xmalloc(sizeof(struct sbucket));
memcpy((void *) *the_bucket, (const void*)array->empty_bucket, sizeof(struct sbucket));
(*the_bucket)->version = array->version;
new_bucket = (struct sbucket*)__objc_xmalloc(sizeof(struct sbucket));
memcpy((void *) new_bucket, (const void*)array->empty_bucket, sizeof(struct sbucket));
new_bucket->version.version = array->version.version;
*the_bucket = new_bucket; /* Prepared for install. */
nbuckets += 1;
} else if ((*the_bucket)->version != array->version) {
} else if ((*the_bucket)->version.version != array->version.version) {
/* Perform lazy copy. */
struct sbucket* old_bucket = *the_bucket;
*the_bucket = (struct sbucket*)__objc_xmalloc(sizeof(struct sbucket));
memcpy( *the_bucket,old_bucket, sizeof(struct sbucket));
(*the_bucket)->version = array->version;
new_bucket = (struct sbucket*)__objc_xmalloc(sizeof(struct sbucket));
memcpy( new_bucket, old_bucket, sizeof(struct sbucket));
new_bucket->version.version = array->version.version;
*the_bucket = new_bucket; /* Prepared for install. */
nbuckets += 1;
}
......@@ -151,42 +207,48 @@ sarray_at_put_safe(struct sarray* array, sidx index, void* element)
struct sarray*
sarray_new (int size, void* default_element)
{
struct sarray* arr;
#ifdef OBJC_SPARSE3
size_t num_indices = ((size-1)/(INDEX_CAPACITY))+1;
struct sindex ** new_indices;
#else /* OBJC_SPARSE2 */
size_t num_indices = ((size-1)/BUCKET_SIZE)+1;
struct sbucket ** new_buckets;
#endif
int counter;
struct sarray* arr;
assert(size > 0);
/* Allocate core array */
arr = (struct sarray*) __objc_xmalloc(sizeof(struct sarray));
arr->version = 0;
narrays += 1;
arr->version.version = 0;
/* Initialize members */
#ifdef OBJC_SPARSE3
arr->capacity = num_indices*INDEX_CAPACITY;
arr->indices = (struct sindex**)
new_indices = (struct sindex**)
__objc_xmalloc(sizeof(struct sindex*)*num_indices);
idxsize += num_indices;
arr->empty_index = (struct sindex*) __objc_xmalloc(sizeof(struct sindex));
arr->empty_index->version = 0;
arr->empty_index->version.version = 0;
narrays += 1;
idxsize += num_indices;
nindices += 1;
#else /* OBJC_SPARSE2 */
arr->capacity = num_indices*BUCKET_SIZE;
arr->buckets = (struct sbucket**)
new_buckets = (struct sbucket**)
__objc_xmalloc(sizeof(struct sbucket*)*num_indices);
narrays += 1;
idxsize += num_indices;
#endif
arr->empty_bucket = (struct sbucket*) __objc_xmalloc(sizeof(struct sbucket));
arr->empty_bucket->version = 0;
arr->empty_bucket->version.version = 0;
nbuckets += 1;
arr->ref_count = 1;
......@@ -200,20 +262,28 @@ sarray_new (int size, void* default_element)
arr->empty_index->buckets[counter] = arr->empty_bucket;
for (counter=0; counter<num_indices; counter++)
arr->indices[counter] = arr->empty_index;
new_indices[counter] = arr->empty_index;
#else /* OBJC_SPARSE2 */
for (counter=0; counter<num_indices; counter++)
arr->buckets[counter] = arr->empty_bucket;
new_buckets[counter] = arr->empty_bucket;
#endif
#ifdef OBJC_SPARSE3
arr->indices = new_indices;
#else /* OBJC_SPARSE2 */
arr->buckets = new_buckets;
#endif
return arr;
}
/* Reallocate the sparse array to hold `newsize' entries */
/* Reallocate the sparse array to hold `newsize' entries
Note: We really allocate and then free. We have to do this to ensure that
any concurrent readers notice the update. */
void
sarray_realloc(struct sarray* array, int newsize)
......@@ -223,11 +293,17 @@ sarray_realloc(struct sarray* array, int newsize)
size_t new_max_index = ((newsize-1)/INDEX_CAPACITY);
size_t rounded_size = (new_max_index+1)*INDEX_CAPACITY;
struct sindex ** new_indices;
struct sindex ** old_indices;
#else /* OBJC_SPARSE2 */
size_t old_max_index = (array->capacity-1)/BUCKET_SIZE;
size_t new_max_index = ((newsize-1)/BUCKET_SIZE);
size_t rounded_size = (new_max_index+1)*BUCKET_SIZE;
struct sbucket ** new_buckets;
struct sbucket ** old_buckets;
#endif
int counter;
......@@ -235,87 +311,72 @@ sarray_realloc(struct sarray* array, int newsize)
assert(newsize > 0);
/* The size is the same, just ignore the request */
if(rounded_size == array->capacity)
if(rounded_size <= array->capacity)
return;
assert(array->ref_count == 1); /* stop if lazy copied... */
if(rounded_size < array->capacity)
/* We are asked to extend the array -- allocate new bucket table, */
/* and insert empty_bucket in newly allocated places. */
if(rounded_size > array->capacity)
{
#ifdef OBJC_SPARSE3
new_max_index += 4;
rounded_size = (new_max_index+1)*INDEX_CAPACITY;
#else /* OBJC_SPARSE2 */
new_max_index += 4;
rounded_size = (new_max_index+1)*BUCKET_SIZE;
#endif
/* update capacity */
array->capacity = rounded_size;
/* free buckets above new_max_index */
for(counter = old_max_index; counter > new_max_index; counter-- ) {
#ifdef OBJC_SPARSE3
struct sindex* idx = array->indices[counter];
if((idx != array->empty_index) && (idx->version == array->version)) {
int c2;
for(c2=0; c2<INDEX_SIZE; c2++) {
struct sbucket* bkt = idx->buckets[c2];
if((bkt != array->empty_bucket) && (bkt->version == array->version))
{
free(bkt);
nbuckets -= 1;
}
}
free(idx);
nindices -= 1;
}
/* alloc to force re-read by any concurrent readers. */
old_indices = array->indices;
new_indices = (struct sindex**)
__objc_xmalloc((new_max_index+1)*sizeof(struct sindex*));
#else /* OBJC_SPARSE2 */
struct sbucket* bkt = array->buckets[counter];
if ((bkt != array->empty_bucket) && (bkt->version == array->version))
{
free(bkt);
nbuckets -= 1;
}
old_buckets = array->buckets;
new_buckets = (struct sbucket**)
__objc_xmalloc((new_max_index+1)*sizeof(struct sbucket*));
#endif
}
/* copy buckets below old_max_index (they are still valid) */
for(counter = 0; counter <= old_max_index; counter++ ) {
#ifdef OBJC_SPARSE3
/* realloc to free the space above new_max_index */
array->indices = (struct sindex**)
__objc_xrealloc(array->indices,
(new_max_index+1)*sizeof(struct sindex*));
new_indices[counter] = old_indices[counter];
#else /* OBJC_SPARSE2 */
array->buckets = (struct sbucket**)
__objc_xrealloc(array->buckets,
(new_max_index+1)*sizeof(struct sbucket*));
#endif
idxsize -= (old_max_index-new_max_index);
return;
}
/* We are asked to extend the array -- reallocate the bucket table, */
/* and insert empty_bucket in newly allocated places. */
if(rounded_size > array->capacity)
{
/* update capacity */
array->capacity = rounded_size;
new_buckets[counter] = old_buckets[counter];
#endif
}
#ifdef OBJC_SPARSE3
/* realloc to make room in table above old_max_index */
array->indices = (struct sindex**)
__objc_xrealloc(array->indices,
(new_max_index+1)*sizeof(struct sindex*));
/* reset entries above old_max_index to empty_bucket */
for(counter = old_max_index+1; counter <= new_max_index; counter++)
array->indices[counter] = array->empty_index;
new_indices[counter] = array->empty_index;
#else /* OBJC_SPARSE2 */
/* realloc to make room in table above old_max_index */
array->buckets = (struct sbucket**)
__objc_xrealloc(array->buckets,
(new_max_index+1)*sizeof(struct sbucket*));
/* reset entries above old_max_index to empty_bucket */
for(counter = old_max_index+1; counter <= new_max_index; counter++)
array->buckets[counter] = array->empty_bucket;
new_buckets[counter] = array->empty_bucket;
#endif
#ifdef OBJC_SPARSE3
/* install the new indices */
array->indices = new_indices;
#else /* OBJC_SPARSE2 */
array->buckets = new_buckets;
#endif
#ifdef OBJC_SPARSE3
/* free the old indices */
sarray_free_garbage(old_indices);
#else /* OBJC_SPARSE2 */
sarray_free_garbage(old_buckets);
#endif
idxsize += (new_max_index-old_max_index);
return;
}
......@@ -326,10 +387,13 @@ sarray_realloc(struct sarray* array, int newsize)
void
sarray_free(struct sarray* array) {
#ifdef OBJC_SPARSE3
size_t old_max_index = (array->capacity-1)/INDEX_CAPACITY;
struct sindex ** old_indices;
#else
size_t old_max_index = (array->capacity-1)/BUCKET_SIZE;
struct sbucket ** old_buckets;
#endif
int counter = 0;
......@@ -338,31 +402,40 @@ sarray_free(struct sarray* array) {
if(--(array->ref_count) != 0) /* There exists copies of me */
return;
#ifdef OBJC_SPARSE3
old_indices = array->indices;
#else
old_buckets = array->buckets;
#endif
if((array->is_copy_of) && ((array->is_copy_of->ref_count - 1) == 0))
sarray_free(array->is_copy_of);
/* Free all entries that do not point to empty_bucket */
for(counter = 0; counter <= old_max_index; counter++ ) {
#ifdef OBJC_SPARSE3
struct sindex* idx = array->indices[counter];
if((idx != array->empty_index) && (idx->version == array->version)) {
struct sindex* idx = old_indices[counter];
if((idx != array->empty_index) &&
(idx->version.version == array->version.version)) {
int c2;
for(c2=0; c2<INDEX_SIZE; c2++) {
struct sbucket* bkt = idx->buckets[c2];
if((bkt != array->empty_bucket) && (bkt->version == array->version))
if((bkt != array->empty_bucket) &&
(bkt->version.version == array->version.version))
{
free(bkt);
sarray_free_garbage(bkt);
nbuckets -= 1;
}
}
free(idx);
sarray_free_garbage(idx);
nindices -= 1;
}
#else /* OBJC_SPARSE2 */
struct sbucket* bkt = array->buckets[counter];
if ((bkt != array->empty_bucket) && (bkt->version == array->version))
if ((bkt != array->empty_bucket) &&
(bkt->version.version == array->version.version))
{
free(bkt);
sarray_free_garbage(bkt);
nbuckets -= 1;
}
#endif
......@@ -370,33 +443,32 @@ sarray_free(struct sarray* array) {
#ifdef OBJC_SPARSE3
/* free empty_index */
if(array->empty_index->version == array->version) {
free(array->empty_index);
if(array->empty_index->version.version == array->version.version) {
sarray_free_garbage(array->empty_index);
nindices -= 1;
}
#endif
/* free empty_bucket */
if(array->empty_bucket->version == array->version) {
free(array->empty_bucket);
if(array->empty_bucket->version.version == array->version.version) {
sarray_free_garbage(array->empty_bucket);
nbuckets -= 1;
}
idxsize -= (old_max_index+1);
narrays -= 1;
#ifdef OBJC_SPARSE3
/* free bucket table */
free(array->indices);
idxsize -= (old_max_index+1);
sarray_free_garbage(array->indices);
#else
/* free bucket table */
free(array->buckets);
idxsize -= (old_max_index+1);
sarray_free_garbage(array->buckets);
#endif
/* free array */
free(array);
narrays -= 1;
sarray_free_garbage(array);
}
/* This is a lazy copy. Only the core of the structure is actually */
......@@ -405,37 +477,46 @@ sarray_free(struct sarray* array) {
struct sarray*
sarray_lazy_copy(struct sarray* oarr)
{
struct sarray* arr;
#ifdef OBJC_SPARSE3
size_t num_indices = ((oarr->capacity-1)/INDEX_CAPACITY)+1;
struct sindex ** new_indices;
#else /* OBJC_SPARSE2 */
size_t num_indices = ((oarr->capacity-1)/BUCKET_SIZE)+1;
struct sbucket ** new_buckets;
#endif
struct sarray* arr;
/* Allocate core array */
arr = (struct sarray*) __objc_xmalloc(sizeof(struct sarray));
memcpy( arr,oarr, sizeof(struct sarray));
arr->version = oarr->version + 1;
arr->is_copy_of = oarr;
oarr->ref_count += 1;
arr = (struct sarray*) __objc_xmalloc(sizeof(struct sarray)); /* !!! */
arr->version.version = oarr->version.version + 1;
#ifdef OBJC_SPARSE3
arr->empty_index = oarr->empty_index;
#endif
arr->empty_bucket = oarr->empty_bucket;
arr->ref_count = 1;
oarr->ref_count += 1;
arr->is_copy_of = oarr;
arr->capacity = oarr->capacity;
#ifdef OBJC_SPARSE3
/* Copy bucket table */
arr->indices = (struct sindex**)
new_indices = (struct sindex**)
__objc_xmalloc(sizeof(struct sindex*)*num_indices);
memcpy( arr->indices,oarr->indices,
memcpy( new_indices,oarr->indices,
sizeof(struct sindex*)*num_indices);
arr->indices = new_indices;
#else
/* Copy bucket table */
arr->buckets = (struct sbucket**)
new_buckets = (struct sbucket**)
__objc_xmalloc(sizeof(struct sbucket*)*num_indices);
memcpy( arr->buckets,oarr->buckets,
memcpy( new_buckets,oarr->buckets,
sizeof(struct sbucket*)*num_indices);
arr->buckets = new_buckets;
#endif
idxsize += num_indices;
narrays += 1;
return arr;
}
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