Initial Persistent HAMT - Map framework

Conflicts:
	erts/emulator/Makefile.in
	erts/emulator/beam/bif.tab
	erts/emulator/beam/erl_gc.c
	erts/emulator/beam/erl_gc.h
	erts/emulator/beam/erl_printf_term.c
	erts/emulator/beam/erl_term.c
	erts/emulator/beam/erl_term.h

1 files changed, 149 insertions, 0 deletions

diff --git a/erts/emulator/beam/erl_hashmap.h b/erts/emulator/beam/erl_hashmap.h
new file mode 100644
index 0000000000..03739fa1f9
--- /dev/null
+++ b/erts/emulator/beam/erl_hashmap.h
@@ -0,0 +1,149 @@
+/*
+ * %CopyrightBegin%
+ * 
+ * Copyright Ericsson AB 2011. All Rights Reserved.
+ * 
+ * The contents of this file are subject to the Erlang Public License,
+ * Version 1.1, (the "License"); you may not use this file except in
+ * compliance with the License. You should have received a copy of the
+ * Erlang Public License along with this software. If not, it can be
+ * retrieved online at http://www.erlang.org/.
+ * 
+ * Software distributed under the License is distributed on an "AS IS"
+ * basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See
+ * the License for the specific language governing rights and limitations
+ * under the License.
+ * 
+ * %CopyrightEnd%
+ */
+
+
+#ifndef __ERL_HASH_H__
+#define __ERL_HASH_H__
+
+#include "sys.h"
+
+Eterm erts_hashmap_get(Eterm key, Eterm map);
+
+/* erl_term.h stuff */
+#define make_hashmap(x)		make_boxed((Eterm*)(x))
+#define make_hashmap_rel 	make_boxed_rel
+#define is_hashmap(x)		(is_boxed((x)) && is_hashmap_header(*boxed_val((x))))
+#define is_hashmap_header(x)	(((x) & (_TAG_HEADER_MASK)) == _TAG_HEADER_HASHMAP)
+#define hashmap_val(x)		_unchecked_boxed_val((x))
+#define hashmap_val_rel(RTERM, BASE) hashmap_val(rterm2wterm(RTERM, BASE))
+
+/* HASH */
+
+
+#if defined(__GNUC__)
+#define hashmap_bitcount(x) 	(Uint32) __builtin_popcount((unsigned int) (x))
+#else
+const Uint32 SK5 = 0x55555555, SK3 = 0x33333333;
+const Uint32 SKF0 = 0xF0F0F0F, SKFF = 0xFF00FF;
+
+/* CTPOP emulation */
+Uint32 hashmap_bitcount(Uint32 map) {
+    map -= (( map >> 1  ) & SK5 );
+    map  = ( map & SK3  ) + (( map >> 2 ) & SK3 );
+    map  = ( map & SKF0 ) + (( map >> 4 ) & SKF0);
+    map +=   map >> 8;
+    return ( map + ( map >> 16)) & 0x3F;
+}
+#endif
+
+/* hamt nodes v2.0
+ * 
+ * node :: leaf | array | bitmap
+ * head
+ */
+
+/* the head-node is a bitmap or array with an untagged size
+ */
+typedef struct hashmap_head_s {
+    Eterm thing_word;
+    Uint size;
+    Eterm items[1];
+} hashmap_head_t;
+ 
+/* the bitmap-node
+ * typedef struct hashmap_bitmap_node_s {
+ *     Eterm thing_word;
+ *     Eterm items[1];
+ * } hashmap_bitmap_node_t;
+ *
+ * the array-node is a tuple
+ * typedef struct hashmap_bitmap_node_s {
+ *     Eterm thing_word; 
+ *     Eterm items[1];
+ * } hashmap_bitmap_node_t;
+ *
+ * the leaf-node
+ * cons-cell
+ */
+
+/* thing_word tagscheme
+ * Need two bits for map subtags
+ *
+ * Original HEADER representation:
+ *
+ *     aaaaaaaaaaaaaaaa aaaaaaaaaatttt00       arity:26, tag:4
+ *
+ * For maps we have:
+ *
+ *     vvvvvvvvvvvvvvvv aaaaaaaamm111100       val:16, arity:8, mtype:2
+ *
+ * unsure about trailing zeros
+ *
+ * map-tag:
+ *     00 - flat map tag (non-hamt) -> val:16 = #items
+ *     01 - map-node bitmap tag     -> val:16 = bitmap
+ *     10 - map-head (array-node)   -> val:16 = 0xffff
+ *     11 - map-head (bitmap-node)  -> val:16 = bitmap
+ */
+
+/* erl_map.h stuff */
+
+#define MAP_HEADER_TAG_SZ                 (2)
+#define MAP_HEADER_ARITY_SZ               (8)
+#define MAP_HEADER_VAL_SZ                 (16)
+
+#define MAP_HEADER_TAG_FLAT               (0x0)
+#define MAP_HEADER_TAG_HAMT_NODE_BITMAP   (0x1)
+#define MAP_HEADER_TAG_HAMT_HEAD_ARRAY    (0x2)
+#define MAP_HEADER_TAG_HAMT_HEAD_BITMAP   (0x3)
+
+#define MAP_HEADER_TYPE(Hdr)  (((Hdr) >> (_HEADER_ARITY_OFFS)) & (0x3))
+#define MAP_HEADER_ARITY(Hdr) (((Hdr) >> (_HEADER_ARITY_OFFS + MAP_HEADER_TAG_SZ)) & (0xff))
+#define MAP_HEADER_VAL(Hdr)   (((Hdr) >> (_HEADER_ARITY_OFFS + MAP_HEADER_TAG_SZ + MAP_HEADER_ARITY_SZ)) & (0xffff))
+
+#define is_hashmap_header_head(x) ((MAP_HEADER_TYPE(x) & (0x2)))
+
+#define MAKE_MAP_HEADER(Type,Arity,Val) \
+    (_make_header(((((Uint16)Val) << MAP_HEADER_ARITY_SZ) | (Arity)) << MAP_HEADER_TAG_SZ | (Type) , _TAG_HEADER_HASHMAP))
+
+#define MAP_HEADER_HAMT_HEAD_ARRAY \
+    MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_HEAD_ARRAY,0x1,0xffff)
+
+#define MAP_HEADER_HAMT_HEAD_BITMAP(Bmp) \
+    MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_HEAD_BITMAP,0x1,Bmp)
+
+#define MAP_HEADER_HAMT_NODE_BITMAP(Bmp) \
+    MAKE_MAP_HEADER(MAP_HEADER_TAG_HAMT_NODE_BITMAP,0x0,Bmp)
+
+#define HAMT_HEAD_EMPTY_SZ     (2)
+#define HAMT_NODE_ARRAY_SZ     (17)
+#define HAMT_HEAD_ARRAY_SZ     (18)
+#define HAMT_NODE_BITMAP_SZ(n) (1 + n)
+#define HAMT_HEAD_BITMAP_SZ(n) (2 + n)
+
+#define _HEADER_MAP_SUBTAG_MASK    (0xfc) /* 2 bits maps tag + 4 bits subtag + 2 ignore bits */
+/* SUBTAG_NODE_ARRAY is in fact a tuple with 16 elements */
+#define HAMT_SUBTAG_NODE_ARRAY   (((16 << _HEADER_ARITY_OFFS) | ARITYVAL_SUBTAG) & _HEADER_MAP_SUBTAG_MASK)
+#define HAMT_SUBTAG_NODE_BITMAP  ((MAP_HEADER_TAG_HAMT_NODE_BITMAP << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
+#define HAMT_SUBTAG_HEAD_ARRAY   ((MAP_HEADER_TAG_HAMT_HEAD_ARRAY << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
+#define HAMT_SUBTAG_HEAD_BITMAP  ((MAP_HEADER_TAG_HAMT_HEAD_BITMAP << _HEADER_ARITY_OFFS) | HASHMAP_SUBTAG)
+
+#define hashmap_index(hash)      (((Uint32)hash) & 0xf)
+
+#endif