gcc/libgo/runtime/go-map-delete.c
Ian Lance Taylor 9490fda67a re PR go/61620 (FAIL: go.test/test/fixedbugs/bug242.go execution, -O2 -g)
PR go/61620

runtime: Don't free tiny blocks in map deletion.

The memory allocator now has a special case for tiny blocks
(smaller than 16 bytes) and they can not be explicitly freed.

From-SVN: r212233
2014-07-02 14:23:45 +00:00

59 lines
1.5 KiB
C

/* go-map-delete.c -- delete an entry from a map.
Copyright 2009 The Go Authors. All rights reserved.
Use of this source code is governed by a BSD-style
license that can be found in the LICENSE file. */
#include <stddef.h>
#include <stdlib.h>
#include "runtime.h"
#include "malloc.h"
#include "go-alloc.h"
#include "go-assert.h"
#include "map.h"
/* Delete the entry matching KEY from MAP. */
void
__go_map_delete (struct __go_map *map, const void *key)
{
const struct __go_map_descriptor *descriptor;
const struct __go_type_descriptor *key_descriptor;
uintptr_t key_offset;
_Bool (*equalfn) (const void*, const void*, uintptr_t);
size_t key_hash;
size_t key_size;
size_t bucket_index;
void **pentry;
if (map == NULL)
return;
descriptor = map->__descriptor;
key_descriptor = descriptor->__map_descriptor->__key_type;
key_offset = descriptor->__key_offset;
key_size = key_descriptor->__size;
__go_assert (key_size != 0 && key_size != -1UL);
equalfn = key_descriptor->__equalfn;
key_hash = key_descriptor->__hashfn (key, key_size);
bucket_index = key_hash % map->__bucket_count;
pentry = map->__buckets + bucket_index;
while (*pentry != NULL)
{
char *entry = (char *) *pentry;
if (equalfn (key, entry + key_offset, key_size))
{
*pentry = *(void **) entry;
if (descriptor->__entry_size >= TinySize)
__go_free (entry);
map->__element_count -= 1;
break;
}
pentry = (void **) entry;
}
}