665 lines
22 KiB
C
665 lines
22 KiB
C
/*
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* This file is part of the Micro Python project, http://micropython.org/
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*
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* The MIT License (MIT)
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*
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* Copyright (c) 2013, 2014 Damien P. George
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*
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* Permission is hereby granted, free of charge, to any person obtaining a copy
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* of this software and associated documentation files (the "Software"), to deal
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* in the Software without restriction, including without limitation the rights
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* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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* copies of the Software, and to permit persons to whom the Software is
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* furnished to do so, subject to the following conditions:
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*
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* The above copyright notice and this permission notice shall be included in
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* all copies or substantial portions of the Software.
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*
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
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* THE SOFTWARE.
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*/
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#include <assert.h>
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#include <stdio.h>
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#include <string.h>
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#include <stdbool.h>
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#include "mpconfig.h"
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#include "misc.h"
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#include "gc.h"
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#include "misc.h"
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#include "qstr.h"
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#include "obj.h"
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#include "runtime.h"
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#if MICROPY_ENABLE_GC
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#if 0 // print debugging info
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#define DEBUG_PRINT (1)
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#define DEBUG_printf DEBUG_printf
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#else // don't print debugging info
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#define DEBUG_printf(...) (void)0
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#endif
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#define WORDS_PER_BLOCK (4)
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#define BYTES_PER_BLOCK (WORDS_PER_BLOCK * BYTES_PER_WORD)
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#define STACK_SIZE (64) // tunable; minimum is 1
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STATIC byte *gc_alloc_table_start;
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STATIC machine_uint_t gc_alloc_table_byte_len;
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#if MICROPY_ENABLE_FINALISER
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STATIC byte *gc_finaliser_table_start;
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#endif
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STATIC machine_uint_t *gc_pool_start;
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STATIC machine_uint_t *gc_pool_end;
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STATIC int gc_stack_overflow;
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STATIC machine_uint_t gc_stack[STACK_SIZE];
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STATIC machine_uint_t *gc_sp;
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STATIC machine_uint_t gc_lock_depth;
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// ATB = allocation table byte
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// 0b00 = FREE -- free block
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// 0b01 = HEAD -- head of a chain of blocks
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// 0b10 = TAIL -- in the tail of a chain of blocks
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// 0b11 = MARK -- marked head block
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#define AT_FREE (0)
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#define AT_HEAD (1)
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#define AT_TAIL (2)
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#define AT_MARK (3)
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#define BLOCKS_PER_ATB (4)
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#define ATB_MASK_0 (0x03)
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#define ATB_MASK_1 (0x0c)
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#define ATB_MASK_2 (0x30)
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#define ATB_MASK_3 (0xc0)
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#define ATB_0_IS_FREE(a) (((a) & ATB_MASK_0) == 0)
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#define ATB_1_IS_FREE(a) (((a) & ATB_MASK_1) == 0)
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#define ATB_2_IS_FREE(a) (((a) & ATB_MASK_2) == 0)
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#define ATB_3_IS_FREE(a) (((a) & ATB_MASK_3) == 0)
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#define BLOCK_SHIFT(block) (2 * ((block) & (BLOCKS_PER_ATB - 1)))
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#define ATB_GET_KIND(block) ((gc_alloc_table_start[(block) / BLOCKS_PER_ATB] >> BLOCK_SHIFT(block)) & 3)
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#define ATB_ANY_TO_FREE(block) do { gc_alloc_table_start[(block) / BLOCKS_PER_ATB] &= (~(AT_MARK << BLOCK_SHIFT(block))); } while (0)
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#define ATB_FREE_TO_HEAD(block) do { gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_HEAD << BLOCK_SHIFT(block)); } while (0)
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#define ATB_FREE_TO_TAIL(block) do { gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_TAIL << BLOCK_SHIFT(block)); } while (0)
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#define ATB_HEAD_TO_MARK(block) do { gc_alloc_table_start[(block) / BLOCKS_PER_ATB] |= (AT_MARK << BLOCK_SHIFT(block)); } while (0)
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#define ATB_MARK_TO_HEAD(block) do { gc_alloc_table_start[(block) / BLOCKS_PER_ATB] &= (~(AT_TAIL << BLOCK_SHIFT(block))); } while (0)
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#define BLOCK_FROM_PTR(ptr) (((ptr) - (machine_uint_t)gc_pool_start) / BYTES_PER_BLOCK)
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#define PTR_FROM_BLOCK(block) (((block) * BYTES_PER_BLOCK + (machine_uint_t)gc_pool_start))
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#define ATB_FROM_BLOCK(bl) ((bl) / BLOCKS_PER_ATB)
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#if MICROPY_ENABLE_FINALISER
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// FTB = finaliser table byte
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// if set, then the corresponding block may have a finaliser
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#define BLOCKS_PER_FTB (8)
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#define FTB_GET(block) ((gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] >> ((block) & 7)) & 1)
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#define FTB_SET(block) do { gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] |= (1 << ((block) & 7)); } while (0)
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#define FTB_CLEAR(block) do { gc_finaliser_table_start[(block) / BLOCKS_PER_FTB] &= (~(1 << ((block) & 7))); } while (0)
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#endif
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// TODO waste less memory; currently requires that all entries in alloc_table have a corresponding block in pool
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void gc_init(void *start, void *end) {
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// align end pointer on block boundary
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end = (void*)((machine_uint_t)end & (~(BYTES_PER_BLOCK - 1)));
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DEBUG_printf("Initializing GC heap: %p..%p = " UINT_FMT " bytes\n", start, end, end - start);
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// calculate parameters for GC (T=total, A=alloc table, F=finaliser table, P=pool; all in bytes):
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// T = A + F + P
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// F = A * BLOCKS_PER_ATB / BLOCKS_PER_FTB
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// P = A * BLOCKS_PER_ATB * BYTES_PER_BLOCK
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// => T = A * (1 + BLOCKS_PER_ATB / BLOCKS_PER_FTB + BLOCKS_PER_ATB * BYTES_PER_BLOCK)
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machine_uint_t total_byte_len = end - start;
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#if MICROPY_ENABLE_FINALISER
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gc_alloc_table_byte_len = total_byte_len * BITS_PER_BYTE / (BITS_PER_BYTE + BITS_PER_BYTE * BLOCKS_PER_ATB / BLOCKS_PER_FTB + BITS_PER_BYTE * BLOCKS_PER_ATB * BYTES_PER_BLOCK);
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#else
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gc_alloc_table_byte_len = total_byte_len / (1 + BITS_PER_BYTE / 2 * BYTES_PER_BLOCK);
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#endif
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gc_alloc_table_start = (byte*)start;
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#if MICROPY_ENABLE_FINALISER
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machine_uint_t gc_finaliser_table_byte_len = (gc_alloc_table_byte_len * BLOCKS_PER_ATB) / BLOCKS_PER_FTB;
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gc_finaliser_table_start = gc_alloc_table_start + gc_alloc_table_byte_len;
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#endif
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machine_uint_t gc_pool_block_len = gc_alloc_table_byte_len * BLOCKS_PER_ATB;
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gc_pool_start = end - gc_pool_block_len * BYTES_PER_BLOCK;
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gc_pool_end = end;
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// clear ATBs
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memset(gc_alloc_table_start, 0, gc_alloc_table_byte_len);
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#if MICROPY_ENABLE_FINALISER
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// clear FTBs
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memset(gc_finaliser_table_start, 0, gc_finaliser_table_byte_len);
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#endif
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// allocate first block because gc_pool_start points there and it will never
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// be freed, so allocating 1 block with null pointers will minimise memory loss
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ATB_FREE_TO_HEAD(0);
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for (int i = 0; i < WORDS_PER_BLOCK; i++) {
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gc_pool_start[i] = 0;
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}
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// unlock the GC
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gc_lock_depth = 0;
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DEBUG_printf("GC layout:\n");
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DEBUG_printf(" alloc table at %p, length " UINT_FMT " bytes, " UINT_FMT " blocks\n", gc_alloc_table_start, gc_alloc_table_byte_len, gc_alloc_table_byte_len * BLOCKS_PER_ATB);
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#if MICROPY_ENABLE_FINALISER
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DEBUG_printf(" finaliser table at %p, length " UINT_FMT " bytes, " UINT_FMT " blocks\n", gc_finaliser_table_start, gc_finaliser_table_byte_len, gc_finaliser_table_byte_len * BLOCKS_PER_FTB);
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#endif
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DEBUG_printf(" pool at %p, length " UINT_FMT " bytes, " UINT_FMT " blocks\n", gc_pool_start, gc_pool_block_len * BYTES_PER_BLOCK, gc_pool_block_len);
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}
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void gc_lock(void) {
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gc_lock_depth++;
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}
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void gc_unlock(void) {
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gc_lock_depth--;
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}
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#define VERIFY_PTR(ptr) ( \
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(ptr & (BYTES_PER_BLOCK - 1)) == 0 /* must be aligned on a block */ \
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&& ptr >= (machine_uint_t)gc_pool_start /* must be above start of pool */ \
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&& ptr < (machine_uint_t)gc_pool_end /* must be below end of pool */ \
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)
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#define VERIFY_MARK_AND_PUSH(ptr) \
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do { \
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if (VERIFY_PTR(ptr)) { \
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machine_uint_t _block = BLOCK_FROM_PTR(ptr); \
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if (ATB_GET_KIND(_block) == AT_HEAD) { \
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/* an unmarked head, mark it, and push it on gc stack */ \
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ATB_HEAD_TO_MARK(_block); \
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if (gc_sp < &gc_stack[STACK_SIZE]) { \
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*gc_sp++ = _block; \
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} else { \
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gc_stack_overflow = 1; \
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} \
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} \
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} \
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} while (0)
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STATIC void gc_drain_stack(void) {
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while (gc_sp > gc_stack) {
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// pop the next block off the stack
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machine_uint_t block = *--gc_sp;
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// work out number of consecutive blocks in the chain starting with this one
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machine_uint_t n_blocks = 0;
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do {
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n_blocks += 1;
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} while (ATB_GET_KIND(block + n_blocks) == AT_TAIL);
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// check this block's children
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machine_uint_t *scan = (machine_uint_t*)PTR_FROM_BLOCK(block);
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for (machine_uint_t i = n_blocks * WORDS_PER_BLOCK; i > 0; i--, scan++) {
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machine_uint_t ptr2 = *scan;
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VERIFY_MARK_AND_PUSH(ptr2);
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}
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}
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}
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STATIC void gc_deal_with_stack_overflow(void) {
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while (gc_stack_overflow) {
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gc_stack_overflow = 0;
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gc_sp = gc_stack;
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// scan entire memory looking for blocks which have been marked but not their children
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for (machine_uint_t block = 0; block < gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) {
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// trace (again) if mark bit set
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if (ATB_GET_KIND(block) == AT_MARK) {
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*gc_sp++ = block;
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gc_drain_stack();
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}
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}
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}
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}
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STATIC void gc_sweep(void) {
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// free unmarked heads and their tails
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int free_tail = 0;
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for (machine_uint_t block = 0; block < gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) {
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switch (ATB_GET_KIND(block)) {
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case AT_HEAD:
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#if MICROPY_ENABLE_FINALISER
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if (FTB_GET(block)) {
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mp_obj_t obj = (mp_obj_t)PTR_FROM_BLOCK(block);
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if (((mp_obj_base_t*)obj)->type != MP_OBJ_NULL) {
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// if the object has a type then see if it has a __del__ method
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mp_obj_t dest[2];
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mp_load_method_maybe(obj, MP_QSTR___del__, dest);
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if (dest[0] != MP_OBJ_NULL) {
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// load_method returned a method
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mp_call_method_n_kw(0, 0, dest);
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}
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}
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// clear finaliser flag
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FTB_CLEAR(block);
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}
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#endif
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free_tail = 1;
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// fall through to free the head
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case AT_TAIL:
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if (free_tail) {
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ATB_ANY_TO_FREE(block);
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}
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break;
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case AT_MARK:
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ATB_MARK_TO_HEAD(block);
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free_tail = 0;
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break;
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}
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}
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}
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void gc_collect_start(void) {
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gc_lock();
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gc_stack_overflow = 0;
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gc_sp = gc_stack;
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}
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void gc_collect_root(void **ptrs, machine_uint_t len) {
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for (machine_uint_t i = 0; i < len; i++) {
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machine_uint_t ptr = (machine_uint_t)ptrs[i];
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VERIFY_MARK_AND_PUSH(ptr);
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gc_drain_stack();
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}
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}
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void gc_collect_end(void) {
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gc_deal_with_stack_overflow();
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gc_sweep();
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gc_unlock();
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}
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void gc_info(gc_info_t *info) {
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info->total = (gc_pool_end - gc_pool_start) * sizeof(machine_uint_t);
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info->used = 0;
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info->free = 0;
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info->num_1block = 0;
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info->num_2block = 0;
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info->max_block = 0;
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for (machine_uint_t block = 0, len = 0; block < gc_alloc_table_byte_len * BLOCKS_PER_ATB; block++) {
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machine_uint_t kind = ATB_GET_KIND(block);
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if (kind == AT_FREE || kind == AT_HEAD) {
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if (len == 1) {
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info->num_1block += 1;
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} else if (len == 2) {
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info->num_2block += 1;
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}
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if (len > info->max_block) {
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info->max_block = len;
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}
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}
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switch (kind) {
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case AT_FREE:
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info->free += 1;
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len = 0;
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break;
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case AT_HEAD:
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info->used += 1;
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len = 1;
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break;
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case AT_TAIL:
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info->used += 1;
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len += 1;
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break;
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case AT_MARK:
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// shouldn't happen
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break;
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}
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}
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info->used *= BYTES_PER_BLOCK;
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info->free *= BYTES_PER_BLOCK;
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}
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void *gc_alloc(machine_uint_t n_bytes, bool has_finaliser) {
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machine_uint_t n_blocks = ((n_bytes + BYTES_PER_BLOCK - 1) & (~(BYTES_PER_BLOCK - 1))) / BYTES_PER_BLOCK;
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DEBUG_printf("gc_alloc(" UINT_FMT " bytes -> " UINT_FMT " blocks)\n", n_bytes, n_blocks);
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// check if GC is locked
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if (gc_lock_depth > 0) {
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return NULL;
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}
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// check for 0 allocation
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if (n_blocks == 0) {
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return NULL;
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}
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machine_uint_t i;
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machine_uint_t end_block;
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machine_uint_t start_block;
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machine_uint_t n_free = 0;
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int collected = 0;
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for (;;) {
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// look for a run of n_blocks available blocks
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for (i = 0; i < gc_alloc_table_byte_len; i++) {
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byte a = gc_alloc_table_start[i];
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if (ATB_0_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 0; goto found; } } else { n_free = 0; }
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if (ATB_1_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 1; goto found; } } else { n_free = 0; }
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if (ATB_2_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 2; goto found; } } else { n_free = 0; }
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if (ATB_3_IS_FREE(a)) { if (++n_free >= n_blocks) { i = i * BLOCKS_PER_ATB + 3; goto found; } } else { n_free = 0; }
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}
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// nothing found!
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if (collected) {
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return NULL;
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}
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DEBUG_printf("gc_alloc(" UINT_FMT "): no free mem, triggering GC\n", n_bytes);
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gc_collect();
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collected = 1;
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}
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// found, ending at block i inclusive
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found:
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// get starting and end blocks, both inclusive
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end_block = i;
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start_block = i - n_free + 1;
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// mark first block as used head
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ATB_FREE_TO_HEAD(start_block);
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// mark rest of blocks as used tail
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// TODO for a run of many blocks can make this more efficient
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for (machine_uint_t bl = start_block + 1; bl <= end_block; bl++) {
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ATB_FREE_TO_TAIL(bl);
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}
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// get pointer to first block
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void *ret_ptr = (void*)(gc_pool_start + start_block * WORDS_PER_BLOCK);
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// zero out the additional bytes of the newly allocated blocks
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// This is needed because the blocks may have previously held pointers
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// to the heap and will not be set to something else if the caller
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// doesn't actually use the entire block. As such they will continue
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// to point to the heap and may prevent other blocks from being reclaimed.
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memset(ret_ptr + n_bytes, 0, (end_block - start_block + 1) * BYTES_PER_BLOCK - n_bytes);
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#if MICROPY_ENABLE_FINALISER
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if (has_finaliser) {
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// clear type pointer in case it is never set
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((mp_obj_base_t*)ret_ptr)->type = MP_OBJ_NULL;
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// set mp_obj flag only if it has a finaliser
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FTB_SET(start_block);
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}
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#endif
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return ret_ptr;
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}
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/*
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void *gc_alloc(machine_uint_t n_bytes) {
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return _gc_alloc(n_bytes, false);
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}
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void *gc_alloc_with_finaliser(machine_uint_t n_bytes) {
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return _gc_alloc(n_bytes, true);
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}
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*/
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// force the freeing of a piece of memory
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void gc_free(void *ptr_in) {
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if (gc_lock_depth > 0) {
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// TODO how to deal with this error?
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return;
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}
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machine_uint_t ptr = (machine_uint_t)ptr_in;
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if (VERIFY_PTR(ptr)) {
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machine_uint_t block = BLOCK_FROM_PTR(ptr);
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if (ATB_GET_KIND(block) == AT_HEAD) {
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// free head and all of its tail blocks
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do {
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ATB_ANY_TO_FREE(block);
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block += 1;
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} while (ATB_GET_KIND(block) == AT_TAIL);
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}
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}
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}
|
|
|
|
machine_uint_t gc_nbytes(void *ptr_in) {
|
|
machine_uint_t ptr = (machine_uint_t)ptr_in;
|
|
|
|
if (VERIFY_PTR(ptr)) {
|
|
machine_uint_t block = BLOCK_FROM_PTR(ptr);
|
|
if (ATB_GET_KIND(block) == AT_HEAD) {
|
|
// work out number of consecutive blocks in the chain starting with this on
|
|
machine_uint_t n_blocks = 0;
|
|
do {
|
|
n_blocks += 1;
|
|
} while (ATB_GET_KIND(block + n_blocks) == AT_TAIL);
|
|
return n_blocks * BYTES_PER_BLOCK;
|
|
}
|
|
}
|
|
|
|
// invalid pointer
|
|
return 0;
|
|
}
|
|
|
|
#if 0
|
|
// old, simple realloc that didn't expand memory in place
|
|
void *gc_realloc(void *ptr, machine_uint_t n_bytes) {
|
|
machine_uint_t n_existing = gc_nbytes(ptr);
|
|
if (n_bytes <= n_existing) {
|
|
return ptr;
|
|
} else {
|
|
bool has_finaliser;
|
|
if (ptr == NULL) {
|
|
has_finaliser = false;
|
|
} else {
|
|
#if MICROPY_ENABLE_FINALISER
|
|
has_finaliser = FTB_GET(BLOCK_FROM_PTR((machine_uint_t)ptr));
|
|
#else
|
|
has_finaliser = false;
|
|
#endif
|
|
}
|
|
void *ptr2 = gc_alloc(n_bytes, has_finaliser);
|
|
if (ptr2 == NULL) {
|
|
return ptr2;
|
|
}
|
|
memcpy(ptr2, ptr, n_existing);
|
|
gc_free(ptr);
|
|
return ptr2;
|
|
}
|
|
}
|
|
|
|
#else // Alternative gc_realloc impl
|
|
|
|
void *gc_realloc(void *ptr_in, machine_uint_t n_bytes) {
|
|
if (gc_lock_depth > 0) {
|
|
return NULL;
|
|
}
|
|
|
|
// check for pure allocation
|
|
if (ptr_in == NULL) {
|
|
return gc_alloc(n_bytes, false);
|
|
}
|
|
|
|
machine_uint_t ptr = (machine_uint_t)ptr_in;
|
|
|
|
// sanity check the ptr
|
|
if (!VERIFY_PTR(ptr)) {
|
|
return NULL;
|
|
}
|
|
|
|
// get first block
|
|
machine_uint_t block = BLOCK_FROM_PTR(ptr);
|
|
|
|
// sanity check the ptr is pointing to the head of a block
|
|
if (ATB_GET_KIND(block) != AT_HEAD) {
|
|
return NULL;
|
|
}
|
|
|
|
// compute number of new blocks that are requested
|
|
machine_uint_t new_blocks = (n_bytes + BYTES_PER_BLOCK - 1) / BYTES_PER_BLOCK;
|
|
|
|
// get the number of consecutive tail blocks and
|
|
// the number of free blocks after last tail block
|
|
// stop if we reach (or are at) end of heap
|
|
machine_uint_t n_free = 0;
|
|
machine_uint_t n_blocks = 1; // counting HEAD block
|
|
machine_uint_t max_block = gc_alloc_table_byte_len * BLOCKS_PER_ATB;
|
|
while (block + n_blocks + n_free < max_block) {
|
|
if (n_blocks + n_free >= new_blocks) {
|
|
// stop as soon as we find enough blocks for n_bytes
|
|
break;
|
|
}
|
|
byte block_type = ATB_GET_KIND(block + n_blocks + n_free);
|
|
switch (block_type) {
|
|
case AT_FREE: n_free++; continue;
|
|
case AT_TAIL: n_blocks++; continue;
|
|
case AT_MARK: assert(0);
|
|
}
|
|
break;
|
|
}
|
|
|
|
// return original ptr if it already has the requested number of blocks
|
|
if (new_blocks == n_blocks) {
|
|
return ptr_in;
|
|
}
|
|
|
|
// check if we can shrink the allocated area
|
|
if (new_blocks < n_blocks) {
|
|
// free unneeded tail blocks
|
|
for (machine_uint_t bl = block + new_blocks; ATB_GET_KIND(bl) == AT_TAIL; bl++) {
|
|
ATB_ANY_TO_FREE(bl);
|
|
}
|
|
return ptr_in;
|
|
}
|
|
|
|
// check if we can expand in place
|
|
if (new_blocks <= n_blocks + n_free) {
|
|
// mark few more blocks as used tail
|
|
for (machine_uint_t bl = block + n_blocks; bl < block + new_blocks; bl++) {
|
|
assert(ATB_GET_KIND(bl) == AT_FREE);
|
|
ATB_FREE_TO_TAIL(bl);
|
|
}
|
|
|
|
// zero out the additional bytes of the newly allocated blocks (see comment above in gc_alloc)
|
|
memset(ptr_in + n_bytes, 0, new_blocks * BYTES_PER_BLOCK - n_bytes);
|
|
|
|
return ptr_in;
|
|
}
|
|
|
|
// can't resize inplace; try to find a new contiguous chain
|
|
void *ptr_out = gc_alloc(n_bytes,
|
|
#if MICROPY_ENABLE_FINALISER
|
|
FTB_GET(block)
|
|
#else
|
|
false
|
|
#endif
|
|
);
|
|
|
|
// check that the alloc succeeded
|
|
if (ptr_out == NULL) {
|
|
return NULL;
|
|
}
|
|
|
|
DEBUG_printf("gc_realloc: allocating new block\n");
|
|
memcpy(ptr_out, ptr_in, n_blocks * BYTES_PER_BLOCK);
|
|
gc_free(ptr_in);
|
|
return ptr_out;
|
|
}
|
|
#endif // Alternative gc_realloc impl
|
|
|
|
void gc_dump_info() {
|
|
gc_info_t info;
|
|
gc_info(&info);
|
|
printf("GC: total: " UINT_FMT ", used: " UINT_FMT ", free: " UINT_FMT "\n", info.total, info.used, info.free);
|
|
printf(" No. of 1-blocks: " UINT_FMT ", 2-blocks: " UINT_FMT ", max blk sz: " UINT_FMT "\n",
|
|
info.num_1block, info.num_2block, info.max_block);
|
|
}
|
|
|
|
void gc_dump_alloc_table(void) {
|
|
printf("GC memory layout; from %p:", gc_pool_start);
|
|
for (machine_uint_t bl = 0; bl < gc_alloc_table_byte_len * BLOCKS_PER_ATB; bl++) {
|
|
if (bl % 64 == 0) {
|
|
printf("\n%04x: ", (uint)bl);
|
|
}
|
|
int c = ' ';
|
|
switch (ATB_GET_KIND(bl)) {
|
|
case AT_FREE: c = '.'; break;
|
|
case AT_HEAD: c = 'h'; break;
|
|
/* this prints the uPy object type of the head block
|
|
case AT_HEAD: {
|
|
machine_uint_t *ptr = gc_pool_start + bl * WORDS_PER_BLOCK;
|
|
if (*ptr == (machine_uint_t)&mp_type_tuple) { c = 'T'; }
|
|
else if (*ptr == (machine_uint_t)&mp_type_list) { c = 'L'; }
|
|
else if (*ptr == (machine_uint_t)&mp_type_dict) { c = 'D'; }
|
|
else if (*ptr == (machine_uint_t)&mp_type_float) { c = 'F'; }
|
|
else if (*ptr == (machine_uint_t)&mp_type_fun_bc) { c = 'B'; }
|
|
else { c = 'h'; }
|
|
break;
|
|
}
|
|
*/
|
|
case AT_TAIL: c = 't'; break;
|
|
case AT_MARK: c = 'm'; break;
|
|
}
|
|
printf("%c", c);
|
|
}
|
|
printf("\n");
|
|
}
|
|
|
|
#if DEBUG_PRINT
|
|
void gc_test(void) {
|
|
machine_uint_t len = 500;
|
|
machine_uint_t *heap = malloc(len);
|
|
gc_init(heap, heap + len / sizeof(machine_uint_t));
|
|
void *ptrs[100];
|
|
{
|
|
machine_uint_t **p = gc_alloc(16, false);
|
|
p[0] = gc_alloc(64, false);
|
|
p[1] = gc_alloc(1, false);
|
|
p[2] = gc_alloc(1, false);
|
|
p[3] = gc_alloc(1, false);
|
|
machine_uint_t ***p2 = gc_alloc(16, false);
|
|
p2[0] = p;
|
|
p2[1] = p;
|
|
ptrs[0] = p2;
|
|
}
|
|
for (int i = 0; i < 25; i+=2) {
|
|
machine_uint_t *p = gc_alloc(i, false);
|
|
printf("p=%p\n", p);
|
|
if (i & 3) {
|
|
//ptrs[i] = p;
|
|
}
|
|
}
|
|
|
|
printf("Before GC:\n");
|
|
gc_dump_alloc_table();
|
|
printf("Starting GC...\n");
|
|
gc_collect_start();
|
|
gc_collect_root(ptrs, sizeof(ptrs) / sizeof(void*));
|
|
gc_collect_end();
|
|
printf("After GC:\n");
|
|
gc_dump_alloc_table();
|
|
}
|
|
#endif
|
|
|
|
#endif // MICROPY_ENABLE_GC
|