mirror of
https://github.com/janet-lang/janet
synced 2024-11-14 12:44:49 +00:00
349 lines
11 KiB
C
349 lines
11 KiB
C
/*
|
|
* Copyright (c) 2017 Calvin Rose
|
|
*
|
|
* Permission is hereby granted, free of charge, to any person obtaining a copy
|
|
* of this software and associated documentation files (the "Software"), to
|
|
* deal in the Software without restriction, including without limitation the
|
|
* rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
|
|
* sell copies of the Software, and to permit persons to whom the Software is
|
|
* furnished to do so, subject to the following conditions:
|
|
*
|
|
* The above copyright notice and this permission notice shall be included in
|
|
* all copies or substantial portions of the Software.
|
|
*
|
|
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
|
|
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
|
|
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
|
|
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
|
|
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
|
|
* FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
|
|
* IN THE SOFTWARE.
|
|
*/
|
|
|
|
#include <dst/dst.h>
|
|
#include "cache.h"
|
|
|
|
/* GC State */
|
|
void *dst_vm_blocks;
|
|
uint32_t dst_vm_memory_interval;
|
|
uint32_t dst_vm_next_collection;
|
|
|
|
/* Helpers for marking the various gc types */
|
|
static void dst_mark_funcenv(DstFuncEnv *env);
|
|
static void dst_mark_funcdef(DstFuncDef *def);
|
|
static void dst_mark_function(DstFunction *func);
|
|
static void dst_mark_array(DstArray *array);
|
|
static void dst_mark_table(DstTable *table);
|
|
static void dst_mark_struct(const DstValue *st);
|
|
static void dst_mark_tuple(const DstValue *tuple);
|
|
static void dst_mark_buffer(DstBuffer *buffer);
|
|
static void dst_mark_string(const uint8_t *str);
|
|
static void dst_mark_fiber(DstFiber *fiber);
|
|
static void dst_mark_udata(void *udata);
|
|
|
|
/* Mark a value */
|
|
void dst_mark(DstValue x) {
|
|
switch (x.type) {
|
|
default: break;
|
|
case DST_STRING:
|
|
case DST_SYMBOL: dst_mark_string(x.as.string); break;
|
|
case DST_FUNCTION: dst_mark_function(x.as.function); break;
|
|
case DST_ARRAY: dst_mark_array(x.as.array); break;
|
|
case DST_TABLE: dst_mark_table(x.as.table); break;
|
|
case DST_STRUCT: dst_mark_struct(x.as.st); break;
|
|
case DST_TUPLE: dst_mark_tuple(x.as.tuple); break;
|
|
case DST_BUFFER: dst_mark_buffer(x.as.buffer); break;
|
|
case DST_FIBER: dst_mark_fiber(x.as.fiber); break;
|
|
case DST_USERDATA: dst_mark_udata(x.as.pointer); break;
|
|
}
|
|
}
|
|
|
|
/* Unpin a value. This enables the GC to collect the value's
|
|
* memory again. */
|
|
void dst_unpin(DstValue x) {
|
|
switch (x.type) {
|
|
default: break;
|
|
case DST_STRING:
|
|
case DST_SYMBOL: dst_unpin_string(x.as.string); break;
|
|
case DST_FUNCTION: dst_unpin_function(x.as.function); break;
|
|
case DST_ARRAY: dst_unpin_array(x.as.array); break;
|
|
case DST_TABLE: dst_unpin_table(x.as.table); break;
|
|
case DST_STRUCT: dst_unpin_struct(x.as.st); break;
|
|
case DST_TUPLE: dst_unpin_tuple(x.as.tuple); break;
|
|
case DST_BUFFER: dst_unpin_buffer(x.as.buffer); break;
|
|
case DST_FIBER: dst_unpin_fiber(x.as.fiber); break;
|
|
case DST_USERDATA: dst_unpin_userdata(x.as.pointer); break;
|
|
}
|
|
}
|
|
|
|
/* Pin a value. This prevents a value from being garbage collected.
|
|
* Needed if the valueis not accesible to the garbage collector, but
|
|
* still in use by the program. For example, a c function that
|
|
* creates a table, and then runs the garbage collector without
|
|
* ever saving the table anywhere (except on the c stack, which
|
|
* the gc cannot inspect). */
|
|
void dst_pin(DstValue x) {
|
|
switch (x.type) {
|
|
default: break;
|
|
case DST_STRING:
|
|
case DST_SYMBOL: dst_pin_string(x.as.string); break;
|
|
case DST_FUNCTION: dst_pin_function(x.as.function); break;
|
|
case DST_ARRAY: dst_pin_array(x.as.array); break;
|
|
case DST_TABLE: dst_pin_table(x.as.table); break;
|
|
case DST_STRUCT: dst_pin_struct(x.as.st); break;
|
|
case DST_TUPLE: dst_pin_tuple(x.as.tuple); break;
|
|
case DST_BUFFER: dst_pin_buffer(x.as.buffer); break;
|
|
case DST_FIBER: dst_pin_fiber(x.as.fiber); break;
|
|
case DST_USERDATA: dst_pin_userdata(x.as.pointer); break;
|
|
}
|
|
}
|
|
|
|
static void dst_mark_string(const uint8_t *str) {
|
|
dst_gc_mark(dst_string_raw(str));
|
|
}
|
|
|
|
static void dst_mark_buffer(DstBuffer *buffer) {
|
|
dst_gc_mark(buffer);
|
|
}
|
|
|
|
static void dst_mark_udata(void *udata) {
|
|
dst_gc_mark(dst_userdata_header(udata));
|
|
}
|
|
|
|
/* Mark a bunch of items in memory */
|
|
static void dst_mark_many(const DstValue *values, uint32_t n) {
|
|
const DstValue *end = values + n;
|
|
while (values < end) {
|
|
dst_mark(*values);
|
|
values += 1;
|
|
}
|
|
}
|
|
|
|
static void dst_mark_array(DstArray *array) {
|
|
if (dst_gc_reachable(array))
|
|
return;
|
|
dst_gc_mark(array);
|
|
dst_mark_many(array->data, array->count);
|
|
}
|
|
|
|
static void dst_mark_table(DstTable *table) {
|
|
if (dst_gc_reachable(table))
|
|
return;
|
|
dst_gc_mark(table);
|
|
dst_mark_many(table->data, table->capacity);
|
|
}
|
|
|
|
static void dst_mark_struct(const DstValue *st) {
|
|
if (dst_gc_reachable(dst_struct_raw(st)))
|
|
return;
|
|
dst_gc_mark(dst_struct_raw(st));
|
|
dst_mark_many(st, dst_struct_capacity(st));
|
|
}
|
|
|
|
static void dst_mark_tuple(const DstValue *tuple) {
|
|
if (dst_gc_reachable(dst_tuple_raw(tuple)))
|
|
return;
|
|
dst_gc_mark(dst_tuple_raw(tuple));
|
|
dst_mark_many(tuple, dst_tuple_length(tuple));
|
|
}
|
|
|
|
/* Helper to mark function environments */
|
|
static void dst_mark_funcenv(DstFuncEnv *env) {
|
|
if (dst_gc_reachable(env))
|
|
return;
|
|
dst_gc_mark(env);
|
|
if (env->offset) {
|
|
/* On stack */
|
|
dst_mark_fiber(env->as.fiber);
|
|
} else {
|
|
/* Not on stack */
|
|
dst_mark_many(env->as.values, env->length);
|
|
}
|
|
}
|
|
|
|
/* GC helper to mark a FuncDef */
|
|
static void dst_mark_funcdef(DstFuncDef *def) {
|
|
uint32_t count, i;
|
|
if (dst_gc_reachable(def))
|
|
return;
|
|
dst_gc_mark(def);
|
|
if (def->constants) {
|
|
count = def->constants_length;
|
|
for (i = 0; i < count; ++i) {
|
|
DstValue v = def->constants[i];
|
|
/* Funcdefs use boolean literals to store other funcdefs */
|
|
if (v.type == DST_BOOLEAN) {
|
|
dst_mark_funcdef((DstFuncDef *) v.as.pointer);
|
|
} else {
|
|
dst_mark(v);
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
static void dst_mark_function(DstFunction *func) {
|
|
uint32_t i;
|
|
uint32_t numenvs;
|
|
if (dst_gc_reachable(func))
|
|
return;
|
|
dst_gc_mark(func);
|
|
numenvs = func->def->environments_length;
|
|
for (i = 0; i < numenvs; ++i)
|
|
if (NULL != func->envs[i])
|
|
dst_mark_funcenv(func->envs[i]);
|
|
dst_mark_funcdef(func->def);
|
|
}
|
|
|
|
static void dst_mark_fiber(DstFiber *fiber) {
|
|
uint32_t i, j;
|
|
DstStackFrame *frame;
|
|
if (dst_gc_reachable(fiber))
|
|
return;
|
|
dst_gc_mark(fiber);
|
|
|
|
i = fiber->frame;
|
|
j = fiber->frametop;
|
|
while (i != 0) {
|
|
frame = (DstStackFrame *)(fiber->data + i - DST_FRAME_SIZE);
|
|
if (NULL != frame->func)
|
|
dst_mark_function(frame->func);
|
|
/* Mark all values in the stack frame */
|
|
dst_mark_many(fiber->data + i, j - i);
|
|
j = i - DST_FRAME_SIZE;
|
|
i = frame->prevframe;
|
|
}
|
|
|
|
if (NULL != fiber->parent)
|
|
dst_mark_fiber(fiber->parent);
|
|
|
|
dst_mark(fiber->ret);
|
|
}
|
|
|
|
/* Deinitialize a block of memory */
|
|
static void dst_deinit_block(DstGCMemoryHeader *block) {
|
|
void *mem = ((char *)(block + 1));
|
|
DstUserdataHeader *h = (DstUserdataHeader *)mem;
|
|
void *smem = mem + 2 * sizeof(uint32_t);
|
|
switch (block->flags & DST_MEM_TYPEBITS) {
|
|
default:
|
|
break; /* Do nothing for non gc types */
|
|
case DST_MEMORY_STRING:
|
|
dst_cache_remove(dst_wrap_string(smem));
|
|
break;
|
|
case DST_MEMORY_ARRAY:
|
|
free(((DstArray*) mem)->data);
|
|
break;
|
|
case DST_MEMORY_TUPLE:
|
|
dst_cache_remove(dst_wrap_tuple(smem));
|
|
break;
|
|
case DST_MEMORY_TABLE:
|
|
free(((DstTable*) mem)->data);
|
|
break;
|
|
case DST_MEMORY_STRUCT:
|
|
dst_cache_remove(dst_wrap_struct(smem));
|
|
break;
|
|
case DST_MEMORY_FIBER:
|
|
free(((DstFiber *) mem)->data);
|
|
break;
|
|
case DST_MEMORY_BUFFER:
|
|
free(((DstBuffer *) mem)->data);
|
|
break;
|
|
case DST_MEMORY_FUNCTION:
|
|
free(((DstFunction *)mem)->envs);
|
|
break;
|
|
case DST_MEMORY_USERDATA:
|
|
if (h->type->finalize)
|
|
h->type->finalize((void *)(h + 1), h->size);
|
|
break;
|
|
case DST_MEMORY_FUNCENV:
|
|
{
|
|
DstFuncEnv *env = (DstFuncEnv *)mem;
|
|
if (0 == env->offset)
|
|
free(env->as.values);
|
|
}
|
|
break;
|
|
case DST_MEMORY_FUNCDEF:
|
|
{
|
|
DstFuncDef *def = (DstFuncDef *)mem;
|
|
/* TODO - get this all with one alloc and one free */
|
|
free(def->environments);
|
|
free(def->constants);
|
|
free(def->bytecode);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
|
|
/* Iterate over all allocated memory, and free memory that is not
|
|
* marked as reachable. Flip the gc color flag for next sweep. */
|
|
void dst_sweep() {
|
|
DstGCMemoryHeader *previous = NULL;
|
|
DstGCMemoryHeader *current = dst_vm_blocks;
|
|
DstGCMemoryHeader *next;
|
|
while (current) {
|
|
next = current->next;
|
|
if (current->flags & (DST_MEM_REACHABLE | DST_MEM_DISABLED)) {
|
|
previous = current;
|
|
} else {
|
|
dst_deinit_block(current);
|
|
if (previous) {
|
|
previous->next = next;
|
|
} else {
|
|
dst_vm_blocks = next;
|
|
}
|
|
free(current);
|
|
}
|
|
current->flags &= ~DST_MEM_REACHABLE;
|
|
current = next;
|
|
}
|
|
}
|
|
|
|
/* Allocate some memory that is tracked for garbage collection */
|
|
void *dst_alloc(DstMemoryType type, size_t size) {
|
|
DstGCMemoryHeader *mdata;
|
|
size_t total = size + sizeof(DstGCMemoryHeader);
|
|
|
|
/* Make sure everything is inited */
|
|
if (NULL == dst_vm_cache) {
|
|
DST_PLEASE_INIT;
|
|
}
|
|
void *mem = malloc(total);
|
|
|
|
/* Check for bad malloc */
|
|
if (NULL == mem) {
|
|
DST_OUT_OF_MEMORY;
|
|
}
|
|
|
|
mdata = (DstGCMemoryHeader *)mem;
|
|
|
|
/* Configure block */
|
|
mdata->flags = type;
|
|
|
|
/* Prepend block to heap list */
|
|
dst_vm_next_collection += size;
|
|
mdata->next = dst_vm_blocks;
|
|
dst_vm_blocks = mdata;
|
|
|
|
return mem + sizeof(DstGCMemoryHeader);
|
|
}
|
|
|
|
/* Run garbage collection */
|
|
void dst_collect() {
|
|
if (dst_vm_fiber)
|
|
dst_mark_fiber(dst_vm_fiber);
|
|
dst_sweep();
|
|
dst_vm_next_collection = 0;
|
|
}
|
|
|
|
/* Free all allocated memory */
|
|
void dst_clear_memory() {
|
|
DstGCMemoryHeader *current = dst_vm_blocks;
|
|
while (current) {
|
|
dst_deinit_block(current);
|
|
DstGCMemoryHeader *next = current->next;
|
|
free(current);
|
|
current = next;
|
|
}
|
|
dst_vm_blocks = NULL;
|
|
}
|