1998-09-21 Ben Elliston <bje@cygnus.com>

        * New directory.  Moved files from ../gcc/objc.


git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@22514 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 522 insertions, 0 deletions

diff --git a/libobjc/sarray.c b/libobjc/sarray.c
new file mode 100644
index 00000000000..7e40fba750f
--- /dev/null
+++ b/libobjc/sarray.c
@@ -0,0 +1,522 @@
+/* Sparse Arrays for Objective C dispatch tables
+   Copyright (C) 1993, 1995, 1996 Free Software Foundation, Inc.
+
+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)
+any later version.
+
+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, 59 Temple Place - Suite 330,
+Boston, MA 02111-1307, 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.  */
+
+#include "objc/sarray.h"
+#include "objc/runtime.h"
+#include <stdio.h>
+#include "assert.h"
+
+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";
+#endif
+
+#ifdef OBJC_SPARSE3
+const char* __objc_sparse3_id = "3 level sparse indices";
+#endif
+
+#ifdef __alpha__
+const void *memcpy (void*, const void*, size_t);
+#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;
+    objc_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) {
+    objc_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
+  size_t boffset;
+  size_t eoffset;
+#ifdef PRECOMPUTE_SELECTORS
+  union sofftype xx; 
+  xx.idx = index;
+#ifdef OBJC_SPARSE3
+  ioffset = xx.off.ioffset;
+#endif
+  boffset = xx.off.boffset;
+  eoffset = xx.off.eoffset;
+#else /* not PRECOMPUTE_SELECTORS */
+#ifdef OBJC_SPARSE3
+  ioffset = index/INDEX_CAPACITY;
+  boffset = (index/BUCKET_SIZE)%INDEX_SIZE;
+  eoffset = index%BUCKET_SIZE;
+#else
+  boffset = index/BUCKET_SIZE;
+  eoffset = index%BUCKET_SIZE;
+#endif
+#endif /* not PRECOMPUTE_SELECTORS */
+
+  assert(soffset_decode(index) < array->capacity); /* Range check */
+
+#ifdef OBJC_SPARSE3
+  the_index = &(array->indices[ioffset]);
+  the_bucket = &((*the_index)->buckets[boffset]);
+#else
+  the_bucket = &(array->buckets[boffset]);
+#endif
+  
+  if ((*the_bucket)->elems[eoffset] == element)
+    return;		/* great! we just avoided a lazy copy */
+
+#ifdef OBJC_SPARSE3
+
+  /* First, perform lazy copy/allocation of index if needed */
+
+  if ((*the_index) == array->empty_index) {
+
+    /* The index was previously empty, allocate a new */
+    new_index = (struct sindex*)objc_malloc(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.version != array->version.version) {
+
+    /* This index must be lazy copied */
+    struct sindex* old_index = *the_index;
+    new_index = (struct sindex*)objc_malloc(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;
+  }
+
+#endif /* OBJC_SPARSE3 */
+
+  /* next, perform lazy allocation/copy of the bucket if needed */
+
+  if ((*the_bucket) == array->empty_bucket) {
+
+    /* The bucket was previously empty (or something like that), */
+    /* allocate a new.  This is the effect of `lazy' allocation */  
+    new_bucket = (struct sbucket*)objc_malloc(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.version != array->version.version) {
+
+    /* Perform lazy copy. */
+    struct sbucket* old_bucket = *the_bucket;
+    new_bucket = (struct sbucket*)objc_malloc(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;
+
+  }
+  (*the_bucket)->elems[eoffset] = element;
+}
+
+void
+sarray_at_put_safe(struct sarray* array, sidx index, void* element)
+{
+  if(soffset_decode(index) >= array->capacity)
+    sarray_realloc(array, soffset_decode(index)+1);
+  sarray_at_put(array, index, 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;
+
+  assert(size > 0);
+
+  /* Allocate core array */
+  arr = (struct sarray*) objc_malloc(sizeof(struct sarray));
+  arr->version.version = 0;
+  
+  /* Initialize members */
+#ifdef OBJC_SPARSE3
+  arr->capacity = num_indices*INDEX_CAPACITY;
+  new_indices = (struct sindex**) 
+    objc_malloc(sizeof(struct sindex*)*num_indices);
+
+  arr->empty_index = (struct sindex*) objc_malloc(sizeof(struct sindex));
+  arr->empty_index->version.version = 0;
+  
+  narrays  += 1;
+  idxsize  += num_indices;
+  nindices += 1;
+
+#else /* OBJC_SPARSE2 */
+  arr->capacity = num_indices*BUCKET_SIZE;
+  new_buckets = (struct sbucket**) 
+    objc_malloc(sizeof(struct sbucket*)*num_indices);
+  
+  narrays  += 1;
+  idxsize  += num_indices;
+
+#endif
+
+  arr->empty_bucket = (struct sbucket*) objc_malloc(sizeof(struct sbucket));
+  arr->empty_bucket->version.version = 0;
+  
+  nbuckets += 1;
+
+  arr->ref_count = 1;
+  arr->is_copy_of = (struct sarray*)0;
+  
+  for (counter=0; counter<BUCKET_SIZE; counter++)
+    arr->empty_bucket->elems[counter] = default_element;
+
+#ifdef OBJC_SPARSE3
+  for (counter=0; counter<INDEX_SIZE; counter++)
+    arr->empty_index->buckets[counter] = arr->empty_bucket;
+
+  for (counter=0; counter<num_indices; counter++)
+    new_indices[counter] = arr->empty_index;
+
+#else /* OBJC_SPARSE2 */
+
+  for (counter=0; counter<num_indices; counter++)
+    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
+   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)
+{
+#ifdef OBJC_SPARSE3
+  size_t old_max_index = (array->capacity-1)/INDEX_CAPACITY;
+  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;
+
+  assert(newsize > 0);
+
+  /* The size is the same, just ignore the request */
+  if(rounded_size <= array->capacity)
+    return;
+
+  assert(array->ref_count == 1);	/* stop if lazy copied... */
+
+  /* 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;
+
+#ifdef OBJC_SPARSE3
+      /* alloc to force re-read by any concurrent readers. */
+      old_indices = array->indices;
+      new_indices = (struct sindex**)
+	objc_malloc((new_max_index+1)*sizeof(struct sindex*));
+#else /* OBJC_SPARSE2 */
+      old_buckets = array->buckets;
+      new_buckets = (struct sbucket**)
+	objc_malloc((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
+	new_indices[counter] = old_indices[counter];
+#else /* OBJC_SPARSE2 */
+	new_buckets[counter] = old_buckets[counter];
+#endif
+      }
+
+#ifdef OBJC_SPARSE3
+      /* reset entries above old_max_index to empty_bucket */
+      for(counter = old_max_index+1; counter <= new_max_index; counter++)
+	new_indices[counter] = array->empty_index;
+#else /* OBJC_SPARSE2 */
+      /* reset entries above old_max_index to empty_bucket */
+      for(counter = old_max_index+1; counter <= new_max_index; counter++)
+	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;
+    }
+}
+
+
+/* Free a sparse array allocated with sarray_new */
+
+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;
+
+  assert(array->ref_count != 0);	/* Freed multiple times!!! */
+
+  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 = 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.version == array->version.version))
+	  {
+	    sarray_free_garbage(bkt);
+	    nbuckets -= 1;
+	  }
+      }
+      sarray_free_garbage(idx);
+      nindices -= 1;
+    }
+#else /* OBJC_SPARSE2 */
+    struct sbucket* bkt = array->buckets[counter];
+    if ((bkt != array->empty_bucket) &&
+	(bkt->version.version == array->version.version))
+      {
+	sarray_free_garbage(bkt);
+	nbuckets -= 1;
+      }
+#endif
+  }
+	
+#ifdef OBJC_SPARSE3  
+  /* free 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.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 */
+  sarray_free_garbage(array->indices);
+
+#else
+  /* free bucket table */
+  sarray_free_garbage(array->buckets);
+
+#endif
+  
+  /* free array */
+  sarray_free_garbage(array);
+}
+
+/* This is a lazy copy.  Only the core of the structure is actually */
+/* copied.   */
+
+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
+
+  /* Allocate core array */
+  arr = (struct sarray*) objc_malloc(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 */
+  new_indices = (struct sindex**) 
+    objc_malloc(sizeof(struct sindex*)*num_indices);
+  memcpy( new_indices,oarr->indices, 
+	sizeof(struct sindex*)*num_indices);
+  arr->indices = new_indices;
+#else 
+  /* Copy bucket table */
+  new_buckets = (struct sbucket**) 
+    objc_malloc(sizeof(struct sbucket*)*num_indices);
+  memcpy( new_buckets,oarr->buckets, 
+	sizeof(struct sbucket*)*num_indices);
+  arr->buckets = new_buckets;
+#endif
+
+  idxsize += num_indices;
+  narrays += 1;
+  
+  return arr;
+}