Introduce parser-specific managed memory allocator with interface jsp_mm_free_all that, upon call, frees all memory allocated with the allocator.

JerryScript-DCO-1.0-Signed-off-by: Ruben Ayrapetyan [email protected]

Author: ruben-ayrapetyan

jerry-core/parser/js/jsp-mm.cpp

@@ -0,0 +1,163 @@
+/* Copyright 2015 Samsung Electronics Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include "jrt.h"
+#include "jsp-mm.h"
+#include "mem-allocator.h"
+#include "mem-heap.h"
+
+/** \addtogroup jsparser ECMAScript parser
+ * @{
+ *
+ * \addtogroup managedmem Managed memory allocation
+ * @{
+ */
+
+/**
+ * Header of a managed block, allocated by parser
+ */
+typedef struct __attribute__ ((alignment (MEM_ALIGNMENT)))
+{
+  mem_cpointer_t prev_block_cp; /**< previous managed block */
+  mem_cpointer_t next_block_cp; /**< next managed block */
+} jsp_mm_header_t;
+
+/**
+ * List used for tracking memory blocks
+ */
+jsp_mm_header_t *jsp_mm_blocks_p = NULL;
+
+/**
+ * Initialize managed memory allocator
+ */
+void
+jsp_mm_init (void)
+{
+  JERRY_ASSERT (jsp_mm_blocks_p == NULL);
+} /* jsp_mm_init */
+
+/**
+ * Finalize managed memory allocator
+ */
+void
+jsp_mm_finalize (void)
+{
+  JERRY_ASSERT (jsp_mm_blocks_p == NULL);
+} /* jsp_mm_finalize */
+
+/**
+ * Recommend allocation size
+ *
+ * Note:
+ *      The interface is used by collection allocators
+ *      for storage of data that takes the specified
+ *      amount of bytes upon allocation, but probably
+ *      would require more.
+ *
+ *      To reduce probability of reallocation in future,
+ *      the allocators can request more space in first
+ *      allocation request.
+ *
+ *      The interface helps to choose appropriate space
+ *      to allocate, considering amount of heap space,
+ *      that would be waste if allocation size
+ *      would not be increased.
+ *
+ * @return recommended allocation size
+ */
+size_t
+jsp_mm_recommend_size (size_t minimum_size) /**< minimum required size */
+{
+  size_t block_and_header_size = mem_heap_recommend_allocation_size (minimum_size + sizeof (jsp_mm_header_t));
+  return block_and_header_size - sizeof (jsp_mm_header_t);
+} /* jsp_mm_recommend_size */
+
+/**
+ * Allocate a managed memory block of specified size
+ *
+ * @return pointer to data space of allocated block
+ */
+void*
+jsp_mm_alloc (size_t size) /**< size of block to allocate */
+{
+  void *ptr_p = mem_heap_alloc_block (size, MEM_HEAP_ALLOC_SHORT_TERM);
+
+  jsp_mm_header_t *tmem_header_p = (jsp_mm_header_t*) ptr_p;
+
+  tmem_header_p->prev_block_cp = MEM_CP_NULL;
+  MEM_CP_SET_POINTER (tmem_header_p->next_block_cp, jsp_mm_blocks_p);
+
+  if (jsp_mm_blocks_p != NULL)
+  {
+    MEM_CP_SET_POINTER (jsp_mm_blocks_p->prev_block_cp, tmem_header_p);
+  }
+
+  jsp_mm_blocks_p = tmem_header_p;
+
+  return (void *) (tmem_header_p + 1);
+} /* jsp_mm_alloc */
+
+/**
+ * Free a managed memory block
+ */
+void
+jsp_mm_free (void *ptr) /**< pointer to data space of allocated block */
+{
+  jsp_mm_header_t *tmem_header_p = ((jsp_mm_header_t *) ptr) - 1;
+
+  jsp_mm_header_t *prev_block_p = MEM_CP_GET_POINTER (jsp_mm_header_t,
+                                                      tmem_header_p->prev_block_cp);
+  jsp_mm_header_t *next_block_p = MEM_CP_GET_POINTER (jsp_mm_header_t,
+                                                      tmem_header_p->next_block_cp);
+
+  if (prev_block_p != NULL)
+  {
+    prev_block_p->next_block_cp = tmem_header_p->next_block_cp;
+  }
+  else
+  {
+    JERRY_ASSERT (jsp_mm_blocks_p == tmem_header_p);
+    jsp_mm_blocks_p = next_block_p;
+  }
+
+  if (next_block_p != NULL)
+  {
+    next_block_p->prev_block_cp = tmem_header_p->prev_block_cp;
+  }
+
+  mem_heap_free_block (tmem_header_p);
+} /* jsp_mm_free */
+
+/**
+ * Free all currently allocated managed memory blocks
+ */
+void
+jsp_mm_free_all (void)
+{
+  while (jsp_mm_blocks_p != NULL)
+  {
+    jsp_mm_header_t *next_block_p = MEM_CP_GET_POINTER (jsp_mm_header_t,
+                                                        jsp_mm_blocks_p->next_block_cp);
+
+    mem_heap_free_block (jsp_mm_blocks_p);
+
+    jsp_mm_blocks_p = next_block_p;
+  }
+} /* jsp_mm_free_all */
+
+/**
+ * @}
+ * @}
+ */

jerry-core/parser/js/jsp-mm.h

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+/* Copyright 2015 Samsung Electronics Co., Ltd.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef JSP_MM_H
+#define JSP_MM_H
+
+#include "jrt-libc-includes.h"
+
+/** \addtogroup jsparser ECMAScript parser
+ * @{
+ *
+ * \addtogroup managedmem Managed memory allocation
+ * @{
+ */
+
+extern void jsp_mm_init (void);
+extern void jsp_mm_finalize (void);
+extern size_t jsp_mm_recommend_size (size_t);
+extern void * jsp_mm_alloc (size_t);
+extern void jsp_mm_free (void *);
+extern void jsp_mm_free_all (void);
+
+/**
+ * @}
+ * @}
+ */
+
+#endif /* !JSP_MM_H */