--- /dev/null
+/*
+ (c) FSF 2002.
+*/
+
+
+#ifndef PRIVATE_GC
+#define PRIVATE_GC
+
+#include "_scm.h"
+
+/* {heap tuning parameters}
+ *
+ * These are parameters for controlling memory allocation. The heap
+ * is the area out of which scm_cons, and object headers are allocated.
+ *
+ * Each heap cell is 8 bytes on a 32 bit machine and 16 bytes on a
+ * 64 bit machine. The units of the _SIZE parameters are bytes.
+ * Cons pairs and object headers occupy one heap cell.
+ *
+ * SCM_INIT_HEAP_SIZE is the initial size of heap. If this much heap is
+ * allocated initially the heap will grow by half its current size
+ * each subsequent time more heap is needed.
+ *
+ * If SCM_INIT_HEAP_SIZE heap cannot be allocated initially, SCM_HEAP_SEG_SIZE
+ * will be used, and the heap will grow by SCM_HEAP_SEG_SIZE when more
+ * heap is needed. SCM_HEAP_SEG_SIZE must fit into type size_t. This code
+ * is in scm_init_storage() and alloc_some_heap() in sys.c
+ *
+ * If SCM_INIT_HEAP_SIZE can be allocated initially, the heap will grow by
+ * SCM_EXPHEAP(scm_heap_size) when more heap is needed.
+ *
+ * SCM_MIN_HEAP_SEG_SIZE is minimum size of heap to accept when more heap
+ * is needed.
+ */
+
+
+/*
+ * Heap size 45000 and 40% min yield gives quick startup and no extra
+ * heap allocation. Having higher values on min yield may lead to
+ * large heaps, especially if code behaviour is varying its
+ * maximum consumption between different freelists.
+ */
+
+/*
+ These values used to be global C variables. However, they're also
+ available through the environment, and having a double interface is
+ confusing. Now they're #defines --hwn.
+ */
+
+#define SCM_DEFAULT_INIT_HEAP_SIZE_1 256*1024
+#define SCM_DEFAULT_MIN_YIELD_1 40
+#define SCM_DEFAULT_INIT_HEAP_SIZE_2 32*1024
+
+/* The following value may seem large, but note that if we get to GC at
+ * all, this means that we have a numerically intensive application
+ */
+#define SCM_DEFAULT_MIN_YIELD_2 40
+
+#define SCM_DEFAULT_MAX_SEGMENT_SIZE (20*1024*1024L)
+
+
+
+#define SCM_MIN_HEAP_SEG_SIZE (8 * SCM_GC_SIZEOF_CARD)
+#define SCM_HEAP_SEG_SIZE (16384L * sizeof (scm_t_cell))
+
+
+#define SCM_DOUBLECELL_ALIGNED_P(x) (((2 * sizeof (scm_t_cell) - 1) & SCM_UNPACK (x)) == 0)
+
+
+#define SCM_GC_CARD_BVEC_SIZE_IN_LONGS \
+ ((SCM_GC_CARD_N_CELLS + SCM_C_BVEC_LONG_BITS - 1) / SCM_C_BVEC_LONG_BITS)
+#define SCM_GC_IN_CARD_HEADERP(x) \
+ (scm_t_cell *) (x) < SCM_GC_CELL_CARD (x) + SCM_GC_CARD_N_HEADER_CELLS
+
+
+int scm_getenv_int (const char *var, int def);
+
+
+typedef enum { return_on_error, abort_on_error } policy_on_error;
+
+/* gc-freelist*/
+
+/*
+ FREELIST:
+
+ A struct holding GC statistics on a particular type of cells.
+*/
+typedef struct scm_t_cell_type_statistics {
+
+ /*
+ heap segment where the last cell was allocated
+ */
+ int heap_segment_idx;
+
+ /* minimum yield on this list in order not to grow the heap
+ */
+ long min_yield;
+
+ /* defines min_yield as percent of total heap size
+ */
+ int min_yield_fraction;
+
+ /* number of cells per object on this list */
+ int span;
+
+ /* number of collected cells during last GC */
+ unsigned long collected;
+
+ /* number of collected cells during penultimate GC */
+ unsigned long collected_1;
+
+ /* total number of cells in heap segments
+ * belonging to this list.
+ */
+ unsigned long heap_size;
+
+
+} scm_t_cell_type_statistics;
+
+
+extern scm_t_cell_type_statistics scm_i_master_freelist;
+extern scm_t_cell_type_statistics scm_i_master_freelist2;
+extern unsigned long scm_gc_cells_collected_1;
+
+void scm_i_adjust_min_yield (scm_t_cell_type_statistics *freelist);
+void scm_i_gc_sweep_freelist_reset (scm_t_cell_type_statistics *freelist);
+int scm_i_gc_grow_heap_p (scm_t_cell_type_statistics * freelist);
+
+
+#define SCM_HEAP_SIZE \
+ (scm_i_master_freelist.heap_size + scm_i_master_freelist2.heap_size)
+
+
+#define SCM_MAX(A, B) ((A) > (B) ? (A) : (B))
+#define SCM_MIN(A, B) ((A) < (B) ? (A) : (B))
+
+/* CELL_P checks a random word whether it has the right form for a
+ pointer to a cell. Use scm_i_find_heap_segment_containing_object
+ to find out whether it actually points to a real cell.
+
+ The right form for a cell pointer is this: the low three bits must
+ be scm_tc3_cons, and when the scm_tc3_cons tag is stripped, the
+ resulting pointer must be correctly aligned.
+ scm_i_initialize_heap_segment_data guarantees that the test below
+ works.
+*/
+#define CELL_P(x) ((SCM_UNPACK(x) & (sizeof(scm_t_cell)-1)) == scm_tc3_cons)
+
+/*
+ gc-mark
+ */
+
+
+void scm_mark_all (void);
+
+
+
+/*
+gc-segment:
+*/
+
+
+
+
+/*
+
+ Cells are stored in a heap-segment: it is a contiguous chunk of
+ memory, that associated with one freelist.
+*/
+
+typedef struct scm_t_heap_segment
+{
+ /*
+ {lower, upper} bounds of the segment
+
+ The upper bound is also the start of the mark space.
+ */
+ scm_t_cell *bounds[2];
+
+ /*
+ If we ever decide to give it back, we could do it with this ptr.
+
+ Note that giving back memory is not very useful; as long we don't
+ touch a chunk of memory, the virtual memory system will keep it
+ swapped out. We could simply forget about a block.
+
+ (not that we do that, but anyway.)
+ */
+
+ void* malloced;
+
+ scm_t_cell * next_free_card;
+
+ /* address of the head-of-freelist pointer for this segment's cells.
+ All segments usually point to the same one, scm_i_freelist. */
+ scm_t_cell_type_statistics *freelist;
+
+ /* number of cells per object in this segment */
+ int span;
+
+
+ /*
+ Is this the first time that the cells are accessed?
+ */
+ int first_time;
+
+} scm_t_heap_segment;
+
+
+
+/*
+
+ A table of segment records is kept that records the upper and
+ lower extents of the segment; this is used during the conservative
+ phase of gc to identify probably gc roots (because they point
+ into valid segments at reasonable offsets).
+
+*/
+extern scm_t_heap_segment ** scm_i_heap_segment_table;
+extern size_t scm_i_heap_segment_table_size;
+
+
+int scm_i_init_card_freelist (scm_t_cell * card, SCM *free_list,scm_t_heap_segment*);
+int scm_i_sweep_card (scm_t_cell * card, SCM *free_list, scm_t_heap_segment*);
+void scm_i_card_statistics (scm_t_cell *p, SCM hashtab, scm_t_heap_segment *seg);
+char const *scm_i_tag_name (scm_t_bits tag); /* MOVEME */
+
+int scm_i_initialize_heap_segment_data (scm_t_heap_segment * segment, size_t requested);
+int scm_i_segment_card_count (scm_t_heap_segment * seg);
+int scm_i_segment_cell_count (scm_t_heap_segment * seg);
+
+void scm_i_clear_segment_mark_space (scm_t_heap_segment *seg);
+scm_t_heap_segment * scm_i_make_empty_heap_segment (scm_t_cell_type_statistics*);
+SCM scm_i_sweep_some_cards (scm_t_heap_segment *seg);
+void scm_i_sweep_segment (scm_t_heap_segment * seg);
+
+void scm_i_heap_segment_statistics (scm_t_heap_segment *seg, SCM tab);
+
+
+int scm_i_insert_segment (scm_t_heap_segment * seg);
+long int scm_i_find_heap_segment_containing_object (SCM obj);
+int scm_i_get_new_heap_segment (scm_t_cell_type_statistics *, policy_on_error);
+void scm_i_clear_mark_space (void);
+void scm_i_sweep_segments (void);
+SCM scm_i_sweep_some_segments (scm_t_cell_type_statistics * fl);
+void scm_i_reset_segments (void);
+void scm_i_sweep_all_segments (char const *reason);
+SCM scm_i_all_segments_statistics (SCM hashtab);
+void scm_i_make_initial_segment (int init_heap_size, scm_t_cell_type_statistics *freelist);
+
+extern long int scm_i_deprecated_memory_return;
+
+
+/*
+ global init funcs.
+ */
+void scm_gc_init_malloc (void);
+void scm_gc_init_freelist (void);
+void scm_gc_init_segments (void);
+void scm_gc_init_mark (void);
+
+
+#endif
projects / lilypond.git / blobdiff