* [PATCH 0/3] patches from https://bugs.ruby-lang.org/issues/12142
@ 2016-04-30 1:04 Eric Wong
2016-04-30 1:04 ` [PATCH 1/3] https://bugs.ruby-lang.org/attachments/download/5931/base.patch Eric Wong
` (2 more replies)
0 siblings, 3 replies; 4+ messages in thread
From: Eric Wong @ 2016-04-30 1:04 UTC (permalink / raw)
To: spew
Applied with whitespace fixes:
https://bugs.ruby-lang.org/attachments/download/5931/base.patch
https://bugs.ruby-lang.org/attachments/download/5932/hash.patch
https://bugs.ruby-lang.org/attachments/download/5933/strong_hash.patch
^ permalink raw reply [flat|nested] 4+ messages in thread
* [PATCH 1/3] https://bugs.ruby-lang.org/attachments/download/5931/base.patch
2016-04-30 1:04 [PATCH 0/3] patches from https://bugs.ruby-lang.org/issues/12142 Eric Wong
@ 2016-04-30 1:04 ` Eric Wong
2016-04-30 1:04 ` [PATCH 2/3] https://bugs.ruby-lang.org/attachments/download/5932/hash.patch Eric Wong
2016-04-30 1:04 ` [PATCH 3/3] https://bugs.ruby-lang.org/attachments/download/5933/strong_hash.patch Eric Wong
2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2016-04-30 1:04 UTC (permalink / raw)
To: spew
From: Vladimir Makarov <vmakarov@redhat.com>
Sat Apr 30 06:25:16 2016 Vladimir Makarov <vmakarov@redhat.com>
* include/ruby/st.h (MAX_ST_INDEX_VAL, st_table_entry): New.
(ST_INDEX_BITS): Remove.
(struct st_table): Add fields entry_power, bin_power, size_ind,
rebuilds_num, bins, entries_start, entries_bound, and entries.
Remove fields num_bins, entries_packed, as. Remove bit field
length from num_entries.
(st_reverse_foreach): Remove.
* st.c: Rewrite top comment. Don't include ccan/list/list.h.
Include <assert.h>.
(PREFETCH, EXPECT, ATTRIBUTE_UNUSED, st_assert, st_hash_t): New.
(struct st_table_entry): Use st_hash_t for hash. Remove next and
olist.
(struct st_packed_entry, ST_DEFAULT_MAX_DENSITY): Remove.
(ST_DEFAULT_INIT_TABLE_SIZE, ST_DEFAULT_PACKED_TABLE_SIZE): Remove.
(PACKED_UNIT): Remove.
(STATIC_ASSERT): Remove definition and usages.
(ST_INIT_VAL, ST_INIT_VAL_BYTE): New.
(malloc, calloc, realloc, free): Redefine as ruby_xmalloc,
ruby_xcalloc, ruby_xrealloc, and ruby_xfree.
(EQUAL): Redefine.
(do_hash): Redefine.
(st_alloc_entry, st_free_entry, st_alloc_table, st_dealloc_table): Remove.
(st_alloc_bins, calloc, st_free_bins, st_realloc_bins): Remove.
(bins,real_entries, PACKED_BINS, PACKED_ENT, PACKED_BINS, PKEY):
Remove.
(PVAL, PHASH, PKEY_SET, PVAL_SET, PHASH_SET, remove_packed_entry):
Remove.
(remove_safe_packed_entry, next_pow2): Remove.
(PTR_EQUAL, struct st_features, MAX_POWER2, features)
(RESERVED_HASH_VAL, RESERVED_HASH_SUBSTITUTION_VAL): New.
(new_size): Remove.
(MINIMAL_POWER2, MAX_POWER2_FOR_TABLES_WITHOUT_BINS, get_power2): New.
(get_bin, set_bin, EMPTY_BIN, DELETED_BIN, ENTRY_BASE): New.
(MARK_BIN_EMPTY, UNDEFINED_ENTRY_IND, UNDEFINED_BIN_IND): New.
(MARK_BIN_DELETED, EMPTY_BIN_P, DELETED_BIN_P): New.
(EMPTY_OR_DELETED_BIN_P, IND_EMPTY_BIN_P, IND_DELETED_BIN_P): New.
(IND_EMPTY_OR_DELETED_BIN_P, MARK_ENTRY_DELETED, DELETED_ENTRY_P):
New.
(get_size_ind, get_bins_num, bins_mask, hash_bin): New.
(get_allocated_entries, bins_size, initialize_bins): New.
(make_tab_empty, st_check): New.
(st_head): Remove.
(st_init_table_with_size, st_clear, st_free_table, st_memsize):
Rewrite.
(PTR_NOT_EQUAL): Remove.
(FOUND_ENTRY): Rename to FOUND_BIN.
(FIND_ENTRY, find_entry, find_packed_index_from): Remove.
(find_packed_index): Remove.
(REBUILD_THRESHOLD): New.
(st_lookup, st_get_key): Rewrite.
(rebuild_table, secondary_hash, find_entry, find_table_entry_ind): New.
(find_table_bin_ind, find_table_bin_ind_direct): New.
(find_table_bin_ptr_and_reserve, rebuild_table_if_necessary): New.
(update_range_for_deleted, st_general_delete, st_general_foreach): New.
(st_general_keys, st_general_values): New.
(new_entry, add_direct, unpack_entries, add_packed_direct): Remove.
(rehash, remove_entry, st_reverse_foreach_check): Remove.
(st_reverse_foreach, get_keys, get_values): Remove.
(st_insert, st_insert2, st_add_direct, st_copy, st_delete): Rewrite.
(st_delete_safe, st_shift, st_cleanup_safe, st_update): Rewrite.
(st_foreach_check, st_foreach, st_keys, st_keys_check): Rewrite.
(st_values, st_values_check): Rewrite.
* ext/-test-/st/foreach/foreach.c (force_unpack_check, unp_fec):
Change tests on packed tables.
(unp_fe): Ditto.
* benchmark/bm_hash_aref_dsym.rb: Increase the number of
iterations.
* benchmark/bm_hash_aref_fix.rb: Ditto.
* benchmark/bm_hash_aref_flo.rb: Ditto.
* benchmark/bm_hash_aref_miss.rb: Ditto.
* benchmark/bm_hash_aref_str.rb: Ditto.
* benchmark/bm_hash_aref_sym.rb: Ditto.
* benchmark/bm_hash_aref_sym_long.rb: Ditto.
* benchmark/bm_hash_flatten.rb: Ditto.
* benchmark/bm_hash_ident_flo.rb: Ditto.
* benchmark/bm_hash_ident_num.rb: Ditto.
* benchmark/bm_hash_ident_obj.rb: Ditto.
* benchmark/bm_hash_ident_str.rb: Ditto.
* benchmark/bm_hash_ident_sym.rb: Ditto.
* benchmark/bm_hash_keys.rb: Ditto.
* benchmark/bm_hash_shift.rb: Ditto.
* benchmark/bm_hash_shift_u16.rb: Ditto.
* benchmark/bm_hash_shift_u24.rb: Ditto.
* benchmark/bm_hash_shift_u32.rb: Ditto.
* benchmark/bm_hash_to_proc.rb: Ditto.
* benchmark/bm_hash_values.rb: Ditto.
* benchmark/bm_hash_aref_dsym_long.rb: Decrease the number of
iterations.
* benchmark/bm_hash_small2.rb : New.
* benchmark/bm_hash_small4.rb: New.
* benchmark/bm_hash_small8.rb: New.
* benchmark/{bm_bighash.rb, bm_hash_long.rb}: New.
---
benchmark/bm_hash_aref_dsym.rb | 2 +-
benchmark/bm_hash_aref_dsym_long.rb | 2 +-
benchmark/bm_hash_aref_fix.rb | 2 +-
benchmark/bm_hash_aref_flo.rb | 2 +-
benchmark/bm_hash_aref_miss.rb | 2 +-
benchmark/bm_hash_aref_str.rb | 2 +-
benchmark/bm_hash_aref_sym.rb | 2 +-
benchmark/bm_hash_aref_sym_long.rb | 2 +-
benchmark/bm_hash_flatten.rb | 2 +-
benchmark/bm_hash_ident_flo.rb | 2 +-
benchmark/bm_hash_ident_num.rb | 2 +-
benchmark/bm_hash_ident_obj.rb | 2 +-
benchmark/bm_hash_ident_str.rb | 2 +-
benchmark/bm_hash_ident_sym.rb | 2 +-
benchmark/bm_hash_keys.rb | 2 +-
benchmark/bm_hash_shift.rb | 2 +-
benchmark/bm_hash_shift_u16.rb | 2 +-
benchmark/bm_hash_shift_u24.rb | 2 +-
benchmark/bm_hash_shift_u32.rb | 2 +-
benchmark/bm_hash_to_proc.rb | 2 +-
benchmark/bm_hash_values.rb | 2 +-
ext/-test-/st/foreach/foreach.c | 12 +-
include/ruby/st.h | 58 +-
st.c | 2348 ++++++++++++++++++++---------------
24 files changed, 1372 insertions(+), 1088 deletions(-)
diff --git a/benchmark/bm_hash_aref_dsym.rb b/benchmark/bm_hash_aref_dsym.rb
index af4f8c3..eb05e1e 100644
--- a/benchmark/bm_hash_aref_dsym.rb
+++ b/benchmark/bm_hash_aref_dsym.rb
@@ -1,4 +1,4 @@
h = {}
syms = ('a'..'z').map { |s| s.to_sym }
syms.each { |s| h[s] = 1 }
-200_000.times { syms.each { |s| h[s] } }
+400_000.times { syms.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_dsym_long.rb b/benchmark/bm_hash_aref_dsym_long.rb
index 9d77593..323050c 100644
--- a/benchmark/bm_hash_aref_dsym_long.rb
+++ b/benchmark/bm_hash_aref_dsym_long.rb
@@ -16,6 +16,6 @@
rng = Random.new(0)
symbol_sample_array = values.sample(sample_size, random: rng).map(&:to_sym)
-3000.times do
+1000.times do
symbol_sample_array.each { |x| symbol_hash[x] }
end
diff --git a/benchmark/bm_hash_aref_fix.rb b/benchmark/bm_hash_aref_fix.rb
index 1346890..009e301 100644
--- a/benchmark/bm_hash_aref_fix.rb
+++ b/benchmark/bm_hash_aref_fix.rb
@@ -1,4 +1,4 @@
h = {}
nums = (1..26).to_a
nums.each { |i| h[i] = i }
-200_000.times { nums.each { |s| h[s] } }
+800_000.times { nums.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_flo.rb b/benchmark/bm_hash_aref_flo.rb
index 2217274..fe12062 100644
--- a/benchmark/bm_hash_aref_flo.rb
+++ b/benchmark/bm_hash_aref_flo.rb
@@ -1,4 +1,4 @@
h = {}
strs = [*1..10000].map! {|i| i.fdiv(10)}
strs.each { |s| h[s] = s }
-50.times { strs.each { |s| h[s] } }
+500.times { strs.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_miss.rb b/benchmark/bm_hash_aref_miss.rb
index b0913dd..061ce47 100644
--- a/benchmark/bm_hash_aref_miss.rb
+++ b/benchmark/bm_hash_aref_miss.rb
@@ -2,4 +2,4 @@
strs = ('a'..'z').to_a.map!(&:freeze)
strs.each { |s| h[s] = s }
strs = ('A'..'Z').to_a
-200_000.times { strs.each { |s| h[s] } }
+500_000.times { strs.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_str.rb b/benchmark/bm_hash_aref_str.rb
index 19439b0..09c5638 100644
--- a/benchmark/bm_hash_aref_str.rb
+++ b/benchmark/bm_hash_aref_str.rb
@@ -1,4 +1,4 @@
h = {}
strs = ('a'..'z').to_a.map!(&:freeze)
strs.each { |s| h[s] = s }
-200_000.times { strs.each { |s| h[s] } }
+500_000.times { strs.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_sym.rb b/benchmark/bm_hash_aref_sym.rb
index f75d163..a302dfd 100644
--- a/benchmark/bm_hash_aref_sym.rb
+++ b/benchmark/bm_hash_aref_sym.rb
@@ -6,4 +6,4 @@
syms.map!(&:to_sym)
end
syms.each { |s| h[s] = s }
-200_000.times { syms.each { |s| h[s] } }
+500_000.times { syms.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_aref_sym_long.rb b/benchmark/bm_hash_aref_sym_long.rb
index 9dab8df..ccc7ca0 100644
--- a/benchmark/bm_hash_aref_sym_long.rb
+++ b/benchmark/bm_hash_aref_sym_long.rb
@@ -10,4 +10,4 @@
syms.map!(&:to_sym)
end
syms.each { |s| h[s] = s }
-200_000.times { syms.each { |s| h[s] } }
+500_000.times { syms.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_flatten.rb b/benchmark/bm_hash_flatten.rb
index e944aae..a4f3235 100644
--- a/benchmark/bm_hash_flatten.rb
+++ b/benchmark/bm_hash_flatten.rb
@@ -4,6 +4,6 @@
h[i] = nil
end
-1000.times do
+2000.times do
h.flatten
end
diff --git a/benchmark/bm_hash_ident_flo.rb b/benchmark/bm_hash_ident_flo.rb
index 0c7edfe..3e660b3 100644
--- a/benchmark/bm_hash_ident_flo.rb
+++ b/benchmark/bm_hash_ident_flo.rb
@@ -1,4 +1,4 @@
h = {}.compare_by_identity
strs = (1..10000).to_a.map!(&:to_f)
strs.each { |s| h[s] = s }
-50.times { strs.each { |s| h[s] } }
+500.times { strs.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_ident_num.rb b/benchmark/bm_hash_ident_num.rb
index b226736..d040bb6 100644
--- a/benchmark/bm_hash_ident_num.rb
+++ b/benchmark/bm_hash_ident_num.rb
@@ -1,4 +1,4 @@
h = {}.compare_by_identity
nums = (1..26).to_a
nums.each { |n| h[n] = n }
-200_000.times { nums.each { |n| h[n] } }
+500_000.times { nums.each { |n| h[n] } }
diff --git a/benchmark/bm_hash_ident_obj.rb b/benchmark/bm_hash_ident_obj.rb
index 4b3b58e..99dd60d 100644
--- a/benchmark/bm_hash_ident_obj.rb
+++ b/benchmark/bm_hash_ident_obj.rb
@@ -1,4 +1,4 @@
h = {}.compare_by_identity
objs = 26.times.map { Object.new }
objs.each { |o| h[o] = o }
-200_000.times { objs.each { |o| h[o] } }
+500_000.times { objs.each { |o| h[o] } }
diff --git a/benchmark/bm_hash_ident_str.rb b/benchmark/bm_hash_ident_str.rb
index 8582b38..b0d219b 100644
--- a/benchmark/bm_hash_ident_str.rb
+++ b/benchmark/bm_hash_ident_str.rb
@@ -1,4 +1,4 @@
h = {}.compare_by_identity
strs = ('a'..'z').to_a
strs.each { |s| h[s] = s }
-200_000.times { strs.each { |s| h[s] } }
+500_000.times { strs.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_ident_sym.rb b/benchmark/bm_hash_ident_sym.rb
index 4c81e3d..f6f48eb 100644
--- a/benchmark/bm_hash_ident_sym.rb
+++ b/benchmark/bm_hash_ident_sym.rb
@@ -1,4 +1,4 @@
h = {}.compare_by_identity
syms = ('a'..'z').to_a.map(&:to_sym)
syms.each { |s| h[s] = s }
-200_000.times { syms.each { |s| h[s] } }
+500_000.times { syms.each { |s| h[s] } }
diff --git a/benchmark/bm_hash_keys.rb b/benchmark/bm_hash_keys.rb
index 6863cd0..406c90a 100644
--- a/benchmark/bm_hash_keys.rb
+++ b/benchmark/bm_hash_keys.rb
@@ -4,6 +4,6 @@
h[i] = nil
end
-5000.times do
+10000.times do
h.keys
end
diff --git a/benchmark/bm_hash_shift.rb b/benchmark/bm_hash_shift.rb
index a645671..3b23eff 100644
--- a/benchmark/bm_hash_shift.rb
+++ b/benchmark/bm_hash_shift.rb
@@ -4,7 +4,7 @@
h[i] = nil
end
-50000.times do
+1000000.times do
k, v = h.shift
h[k] = v
end
diff --git a/benchmark/bm_hash_shift_u16.rb b/benchmark/bm_hash_shift_u16.rb
index ec800d0..517a878 100644
--- a/benchmark/bm_hash_shift_u16.rb
+++ b/benchmark/bm_hash_shift_u16.rb
@@ -4,7 +4,7 @@
h[i] = nil
end
-300000.times do
+1000000.times do
k, v = h.shift
h[k] = v
end
diff --git a/benchmark/bm_hash_shift_u24.rb b/benchmark/bm_hash_shift_u24.rb
index de4e0fa..d74bf4e 100644
--- a/benchmark/bm_hash_shift_u24.rb
+++ b/benchmark/bm_hash_shift_u24.rb
@@ -4,7 +4,7 @@
h[i] = nil
end
-300000.times do
+1000000.times do
k, v = h.shift
h[k] = v
end
diff --git a/benchmark/bm_hash_shift_u32.rb b/benchmark/bm_hash_shift_u32.rb
index 656aa55..ea19e6f 100644
--- a/benchmark/bm_hash_shift_u32.rb
+++ b/benchmark/bm_hash_shift_u32.rb
@@ -4,7 +4,7 @@
h[i] = nil
end
-300000.times do
+1000000.times do
k, v = h.shift
h[k] = v
end
diff --git a/benchmark/bm_hash_to_proc.rb b/benchmark/bm_hash_to_proc.rb
index 2b675bf..18e02bd 100644
--- a/benchmark/bm_hash_to_proc.rb
+++ b/benchmark/bm_hash_to_proc.rb
@@ -4,6 +4,6 @@
h[i] = nil
end
-5000.times do |i|
+500000.times do |i|
[i].map(&h)
end
diff --git a/benchmark/bm_hash_values.rb b/benchmark/bm_hash_values.rb
index 0694413..f9d8f45 100644
--- a/benchmark/bm_hash_values.rb
+++ b/benchmark/bm_hash_values.rb
@@ -4,6 +4,6 @@
h[i] = nil
end
-5000.times do
+10000.times do
h.values
end
diff --git a/ext/-test-/st/foreach/foreach.c b/ext/-test-/st/foreach/foreach.c
index 1e0fd51..209b535 100644
--- a/ext/-test-/st/foreach/foreach.c
+++ b/ext/-test-/st/foreach/foreach.c
@@ -14,13 +14,13 @@ force_unpack_check(struct checker *c, st_data_t key, st_data_t val)
if (c->nr == 0) {
st_data_t i;
- if (!c->tbl->entries_packed) rb_bug("should be packed\n");
+ if (c->tbl->bins != NULL) rb_bug("should be packed\n");
/* force unpacking during iteration: */
for (i = 1; i < expect_size; i++)
st_add_direct(c->tbl, i, i);
- if (c->tbl->entries_packed) rb_bug("should be unpacked\n");
+ if (c->tbl->bins == NULL) rb_bug("should be unpacked\n");
}
if (key != c->nr) {
@@ -84,7 +84,7 @@ unp_fec(VALUE self, VALUE test)
st_add_direct(tbl, 0, 0);
- if (!tbl->entries_packed) rb_bug("should still be packed\n");
+ if (tbl->bins != NULL) rb_bug("should still be packed\n");
st_foreach_check(tbl, unp_fec_i, (st_data_t)&c, -1);
@@ -98,7 +98,7 @@ unp_fec(VALUE self, VALUE test)
(VALUE)c.nr, (VALUE)expect_size);
}
- if (tbl->entries_packed) rb_bug("should be unpacked\n");
+ if (tbl->bins == NULL) rb_bug("should be unpacked\n");
st_free_table(tbl);
@@ -145,7 +145,7 @@ unp_fe(VALUE self, VALUE test)
st_add_direct(tbl, 0, 0);
- if (!tbl->entries_packed) rb_bug("should still be packed\n");
+ if (tbl->bins != NULL) rb_bug("should still be packed\n");
st_foreach(tbl, unp_fe_i, (st_data_t)&c);
@@ -159,7 +159,7 @@ unp_fe(VALUE self, VALUE test)
(VALUE)c.nr, (VALUE)expect_size);
}
- if (tbl->entries_packed) rb_bug("should be unpacked\n");
+ if (tbl->bins == NULL) rb_bug("should be unpacked\n");
st_free_table(tbl);
diff --git a/include/ruby/st.h b/include/ruby/st.h
index 190bad2..b845755 100644
--- a/include/ruby/st.h
+++ b/include/ruby/st.h
@@ -1,6 +1,8 @@
-/* This is a public domain general purpose hash table package written by Peter Moore @ UCB. */
+/* This is a public domain general purpose hash table package
+ originally written by Peter Moore @ UCB.
-/* @(#) st.h 5.1 89/12/14 */
+ The hash table data strutures were redesigned and the package was
+ rewritten by Vladimir Makarov <vmakarov@redhat.com>. */
#ifndef RUBY_ST_H
#define RUBY_ST_H 1
@@ -46,6 +48,10 @@ typedef unsigned LONG_LONG st_data_t;
typedef struct st_table st_table;
typedef st_data_t st_index_t;
+
+/* Maximal value of unsigned integer type st_index_t. */
+#define MAX_ST_INDEX_VAL (~(st_index_t) 0)
+
typedef int st_compare_func(st_data_t, st_data_t);
typedef st_index_t st_hash_func(st_data_t);
@@ -57,8 +63,6 @@ struct st_hash_type {
st_index_t (*hash)(ANYARGS /*st_data_t*/); /* st_hash_func* */
};
-#define ST_INDEX_BITS (sizeof(st_index_t) * CHAR_BIT)
-
#if defined(HAVE_BUILTIN___BUILTIN_CHOOSE_EXPR) && defined(HAVE_BUILTIN___BUILTIN_TYPES_COMPATIBLE_P)
# define ST_DATA_COMPATIBLE_P(type) \
__builtin_choose_expr(__builtin_types_compatible_p(type, st_data_t), 1, 0)
@@ -66,33 +70,26 @@ struct st_hash_type {
# define ST_DATA_COMPATIBLE_P(type) 0
#endif
+typedef struct st_table_entry st_table_entry;
+
+struct st_table_entry; /* defined in st.c */
+
struct st_table {
+ /* Cached features of the table -- see st.c for more details. */
+ unsigned char entry_power, bin_power, size_ind;
+ /* How many times the table was rebuilt. */
+ unsigned int rebuilds_num;
const struct st_hash_type *type;
- st_index_t num_bins;
- unsigned int entries_packed : 1;
-#ifdef __GNUC__
- /*
- * C spec says,
- * A bit-field shall have a type that is a qualified or unqualified
- * version of _Bool, signed int, unsigned int, or some other
- * implementation-defined type. It is implementation-defined whether
- * atomic types are permitted.
- * In short, long and long long bit-field are implementation-defined
- * feature. Therefore we want to suppress a warning explicitly.
- */
- __extension__
-#endif
- st_index_t num_entries : ST_INDEX_BITS - 1;
- union {
- struct {
- struct st_table_entry **bins;
- void *private_list_head[2];
- } big;
- struct {
- struct st_packed_entry *entries;
- st_index_t real_entries;
- } packed;
- } as;
+ /* Number of entries currently in the table. */
+ st_index_t num_entries;
+ /* Array of bins used for access by keys. */
+ st_index_t *bins;
+ /* Start and bound index of entries in array entries.
+ entries_starts and entries_bound are in interval
+ [0,allocated_entries]. */
+ st_index_t entries_start, entries_bound;
+ /* Array of size 2^entry_power. */
+ st_table_entry *entries;
};
#define st_is_member(table,key) st_lookup((table),(key),(st_data_t *)0)
@@ -121,13 +118,13 @@ typedef int st_update_callback_func(st_data_t *key, st_data_t *value, st_data_t
int st_update(st_table *table, st_data_t key, st_update_callback_func *func, st_data_t arg);
int st_foreach(st_table *, int (*)(ANYARGS), st_data_t);
int st_foreach_check(st_table *, int (*)(ANYARGS), st_data_t, st_data_t);
-int st_reverse_foreach(st_table *, int (*)(ANYARGS), st_data_t);
st_index_t st_keys(st_table *table, st_data_t *keys, st_index_t size);
st_index_t st_keys_check(st_table *table, st_data_t *keys, st_index_t size, st_data_t never);
st_index_t st_values(st_table *table, st_data_t *values, st_index_t size);
st_index_t st_values_check(st_table *table, st_data_t *values, st_index_t size, st_data_t never);
void st_add_direct(st_table *, st_data_t, st_data_t);
void st_free_table(st_table *);
+size_t st_memsize(const st_table *);
void st_cleanup_safe(st_table *, st_data_t);
void st_clear(st_table *);
st_table *st_copy(st_table *);
@@ -137,7 +134,6 @@ int st_locale_insensitive_strcasecmp(const char *s1, const char *s2);
int st_locale_insensitive_strncasecmp(const char *s1, const char *s2, size_t n);
#define st_strcasecmp st_locale_insensitive_strcasecmp
#define st_strncasecmp st_locale_insensitive_strncasecmp
-size_t st_memsize(const st_table *);
st_index_t st_hash(const void *ptr, size_t len, st_index_t h);
st_index_t st_hash_uint32(st_index_t h, uint32_t i);
st_index_t st_hash_uint(st_index_t h, st_index_t i);
diff --git a/st.c b/st.c
index 9672c2e..f63dd56 100644
--- a/st.c
+++ b/st.c
@@ -1,6 +1,99 @@
-/* This is a public domain general purpose hash table package written by Peter Moore @ UCB. */
-
-/* static char sccsid[] = "@(#) st.c 5.1 89/12/14 Crucible"; */
+/* This is a public domain general purpose hash table package
+ originally written by Peter Moore @ UCB.
+
+ The hash table data structures were redesigned and the package was
+ rewritten by Vladimir Makarov <vmakarov@redhat.com>. */
+
+/* The original package implemented classic bucket-based hash tables
+ with entries doubly linked for an access by their insertion order.
+ To decrease pointer chasing and as a consequence to improve a data
+ locality the current implementation is based on storing entries in
+ an array and using hash tables with open addressing. The current
+ entries are more compact in comparison with the original ones and
+ this also improves the data locality.
+
+ The hash table has two arrays called *bins* and *entries*.
+
+ bins:
+ -------
+ | | entries array:
+ |-------| --------------------------------
+ | index | | | entry: | | |
+ |-------| | | | | |
+ | ... | | ... | hash | ... | ... |
+ |-------| | | key | | |
+ | empty | | | record | | |
+ |-------| --------------------------------
+ | ... | ^ ^
+ |-------| |_ entries start |_ entries bound
+ |deleted|
+ -------
+
+ o The entry array contains table entries in the same order as they
+ were inserted.
+
+ When the first entry is deleted, a variable containing index of
+ the current first entry (*entries start*) is changed. In all
+ other cases of the deletion, we just mark the entry as deleted by
+ using a reserved hash value.
+
+ Such organization of the entry storage makes operations of the
+ table shift and the entries traversal very fast.
+
+ o The bins provide access to the entries by their keys. The
+ key hash is mapped to a bin containing *index* of the
+ corresponding entry in the entry array.
+
+ The bin array size is always power of two, it makes mapping very
+ fast by using the corresponding lower bits of the hash.
+ Generally it is not a good idea to ignore some part of the hash.
+ But alternative approach is worse. For example, we could use a
+ modulo operation for mapping and a prime number for the size of
+ the bin array. Unfortunately, the modulo operation for big
+ 64-bit numbers are extremely slow (it takes more than 100 cycles
+ on modern Intel CPUs).
+
+ Still other bits of the hash value are used when the mapping
+ results in a collision. In this case we use a secondary hash
+ value which is a result of a function of the collision bin
+ index and the original hash value. The function choice
+ guarantees that we can traverse all bins and finally find the
+ corresponding bin as after several iterations the function
+ becomes a full cycle linear congruential generator because it
+ satisfies requirements of the Hull-Dobell theorem.
+
+ When an entry is removed from the table besides marking the
+ hash in the corresponding entry described above, we also mark
+ the bin by a special value in order to find entries which had
+ a collision with the removed entries.
+
+ There are two reserved values for the bins. One denotes an
+ empty bin, another one denotes a bin for a deleted entry.
+
+ o The length of the bin array is at least two times more than the
+ entry array length. This keeps the table load factor healthy.
+ The trigger of rebuilding the table is always a case when we can
+ not insert an entry anymore at the entries bound. We could
+ change the entries bound too in case of deletion but than we need
+ a special code to count bins with corresponding deleted entries
+ and reset the bin values when there are too many bins
+ corresponding deleted entries
+
+ Table rebuilding is done by creation of a new entry array and
+ bins of an appropriate size. We also try to reuse the arrays
+ in some cases by compacting the array and removing deleted
+ entries.
+
+ o To save memory very small tables have no allocated arrays
+ bins. We use a linear search for an access by a key.
+
+ o To save more memory we use 8-, 16-, 32- and 64- bit indexes in
+ bins depending on the current hash table size.
+
+ This implementation speeds up the Ruby hash table benchmarks in
+ average by more 40% on Intel Haswell CPU.
+
+*/
#ifdef NOT_RUBY
#include "regint.h"
@@ -14,46 +107,33 @@
#include <stdlib.h>
#endif
#include <string.h>
-#include "ccan/list/list.h"
+#include <assert.h>
+
+#ifdef __GNUC__
+#define PREFETCH(addr, write_p) __builtin_prefetch(addr, write_p)
+#define EXPECT(expr, val) __builtin_expect(expr, val)
+#define ATTRIBUTE_UNUSED __attribute__((unused))
+#else
+#define PREFETCH(addr, write_p)
+#define EXPECT(expr, val) (expr)
+#define ATTRIBUTE_UNUSED
+#endif
+
+#ifdef ST_DEBUG
+#define st_assert(cond) assert(cond)
+#else
+#define st_assert(cond) ((void)(0 && (cond)))
+#endif
-typedef struct st_table_entry st_table_entry;
+/* The type of hashes. */
+typedef st_index_t st_hash_t;
struct st_table_entry {
- st_index_t hash;
+ st_hash_t hash;
st_data_t key;
st_data_t record;
- st_table_entry *next;
- struct list_node olist;
};
-typedef struct st_packed_entry {
- st_index_t hash;
- st_data_t key, val;
-} st_packed_entry;
-
-#ifndef STATIC_ASSERT
-#define STATIC_ASSERT(name, expr) typedef int static_assert_##name##_check[(expr) ? 1 : -1]
-#endif
-
-#define ST_DEFAULT_MAX_DENSITY 5
-#define ST_DEFAULT_INIT_TABLE_SIZE 16
-#define ST_DEFAULT_PACKED_TABLE_SIZE 18
-#define PACKED_UNIT (int)(sizeof(st_packed_entry) / sizeof(st_table_entry*))
-#define MAX_PACKED_HASH (int)(ST_DEFAULT_PACKED_TABLE_SIZE * sizeof(st_table_entry*) / sizeof(st_packed_entry))
-
-STATIC_ASSERT(st_packed_entry, sizeof(st_packed_entry) == sizeof(st_table_entry*[PACKED_UNIT]));
-STATIC_ASSERT(st_packed_bins, sizeof(st_packed_entry[MAX_PACKED_HASH]) <= sizeof(st_table_entry*[ST_DEFAULT_PACKED_TABLE_SIZE]));
-
- /*
- * DEFAULT_MAX_DENSITY is the default for the largest we allow the
- * average number of items per bin before increasing the number of
- * bins
- *
- * DEFAULT_INIT_TABLE_SIZE is the default for the number of bins
- * allocated initially
- *
- */
-
#define type_numhash st_hashtype_num
const struct st_hash_type st_hashtype_num = {
st_numcmp,
@@ -73,105 +153,364 @@ static const struct st_hash_type type_strcasehash = {
strcasehash,
};
-static void rehash(st_table *);
+/* Value used to catch uninitialized entries/bins during debugging.
+ There is a possibility for a false alarm, but its probability is
+ extremely small. */
+#define ST_INIT_VAL 0xafafafafafafafaf
+#define ST_INIT_VAL_BYTE 0xafa
#ifdef RUBY
#undef malloc
#undef realloc
#undef calloc
#undef free
-#define malloc xmalloc
-#define calloc xcalloc
-#define realloc xrealloc
-#define free(x) xfree(x)
-#endif
-
-#define EQUAL(table,x,ent) ((x)==(ent)->key || (*(table)->type->compare)((x),(ent)->key) == 0)
-
-#define do_hash(key,table) (st_index_t)(*(table)->type->hash)((key))
-#define hash_pos(h,n) ((h) & (n - 1))
-
-/* preparation for possible allocation improvements */
-#define st_alloc_entry() (st_table_entry *)malloc(sizeof(st_table_entry))
-#define st_free_entry(entry) free(entry)
-#define st_alloc_table() (st_table *)malloc(sizeof(st_table))
-#define st_dealloc_table(table) free(table)
-#define st_alloc_bins(size) (st_table_entry **)calloc(size, sizeof(st_table_entry *))
-#define st_free_bins(bins, size) free(bins)
-static inline st_table_entry**
-st_realloc_bins(st_table_entry **bins, st_index_t newsize, st_index_t oldsize)
-{
- bins = (st_table_entry **)realloc(bins, newsize * sizeof(st_table_entry *));
- MEMZERO(bins, st_table_entry*, newsize);
- return bins;
-}
-
-/* Shortcut */
-#define bins as.big.bins
-#define real_entries as.packed.real_entries
-
-/* preparation for possible packing improvements */
-#define PACKED_BINS(table) ((table)->as.packed.entries)
-#define PACKED_ENT(table, i) PACKED_BINS(table)[i]
-#define PKEY(table, i) PACKED_ENT((table), (i)).key
-#define PVAL(table, i) PACKED_ENT((table), (i)).val
-#define PHASH(table, i) PACKED_ENT((table), (i)).hash
-#define PKEY_SET(table, i, v) (PKEY((table), (i)) = (v))
-#define PVAL_SET(table, i, v) (PVAL((table), (i)) = (v))
-#define PHASH_SET(table, i, v) (PHASH((table), (i)) = (v))
-
-/* this function depends much on packed layout, so that it placed here */
-static inline void
-remove_packed_entry(st_table *table, st_index_t i)
-{
- table->real_entries--;
- table->num_entries--;
- if (i < table->real_entries) {
- MEMMOVE(&PACKED_ENT(table, i), &PACKED_ENT(table, i+1),
- st_packed_entry, table->real_entries - i);
- }
-}
+#define malloc ruby_xmalloc
+#define calloc ruby_xcalloc
+#define realloc ruby_xrealloc
+#define free ruby_xfree
+#endif
-static inline void
-remove_safe_packed_entry(st_table *table, st_index_t i, st_data_t never)
-{
- table->num_entries--;
- PKEY_SET(table, i, never);
- PVAL_SET(table, i, never);
- PHASH_SET(table, i, 0);
-}
+#define EQUAL(tab,x,y) ((x) == (y) || (*(tab)->type->compare)((x),(y)) == 0)
+#define PTR_EQUAL(tab, ptr, hash_val, key) \
+ ((ptr)->hash == (hash_val) && EQUAL((tab), (key), (ptr)->key))
+
+/* Features of a table. */
+struct st_features {
+ /* Power of 2 used for number of allocated entries. */
+ unsigned char entry_power;
+ /* Power of 2 used for number of allocated bins. Depending on the
+ table size, the number of bins is 2-4 times more than the
+ number of entries. */
+ unsigned char bin_power;
+ /* Enumeration of sizes of bins (8-bit, 16-bit etc). */
+ unsigned char size_ind;
+ /* Bins are packed in words of type st_index_t. The following is
+ a size of bins counted by words. */
+ st_index_t bins_words;
+};
-static st_index_t
-next_pow2(st_index_t x)
-{
- x |= x >> 1;
- x |= x >> 2;
- x |= x >> 4;
- x |= x >> 8;
- x |= x >> 16;
+/* Features of all possible size tables. */
#if SIZEOF_ST_INDEX_T == 8
- x |= x >> 32;
+#define MAX_POWER2 62
+struct st_features features[] = {
+ {0, 2, 0, 0x0},
+ {1, 3, 0, 0x1},
+ {2, 4, 0, 0x2},
+ {3, 5, 0, 0x4},
+ {4, 6, 0, 0x8},
+ {5, 7, 0, 0x10},
+ {6, 8, 0, 0x20},
+ {7, 9, 0, 0x40},
+ {8, 10, 1, 0x100},
+ {9, 11, 1, 0x200},
+ {10, 12, 1, 0x400},
+ {11, 13, 1, 0x800},
+ {12, 14, 1, 0x1000},
+ {13, 15, 1, 0x2000},
+ {14, 16, 1, 0x4000},
+ {15, 17, 1, 0x8000},
+ {16, 18, 2, 0x20000},
+ {17, 19, 2, 0x40000},
+ {18, 20, 2, 0x80000},
+ {19, 21, 2, 0x100000},
+ {20, 22, 2, 0x200000},
+ {21, 23, 2, 0x400000},
+ {22, 24, 2, 0x800000},
+ {23, 25, 2, 0x1000000},
+ {24, 26, 2, 0x2000000},
+ {25, 27, 2, 0x4000000},
+ {26, 28, 2, 0x8000000},
+ {27, 29, 2, 0x10000000},
+ {28, 30, 2, 0x20000000},
+ {29, 31, 2, 0x40000000},
+ {30, 32, 2, 0x80000000},
+ {31, 33, 2, 0x100000000},
+ {32, 33, 3, 0x200000000},
+ {33, 34, 3, 0x400000000},
+ {34, 35, 3, 0x800000000},
+ {35, 36, 3, 0x1000000000},
+ {36, 37, 3, 0x2000000000},
+ {37, 38, 3, 0x4000000000},
+ {38, 39, 3, 0x8000000000},
+ {39, 40, 3, 0x10000000000},
+ {40, 41, 3, 0x20000000000},
+ {41, 42, 3, 0x40000000000},
+ {42, 43, 3, 0x80000000000},
+ {43, 44, 3, 0x100000000000},
+ {44, 45, 3, 0x200000000000},
+ {45, 46, 3, 0x400000000000},
+ {46, 47, 3, 0x800000000000},
+ {47, 48, 3, 0x1000000000000},
+ {48, 49, 3, 0x2000000000000},
+ {49, 50, 3, 0x4000000000000},
+ {50, 51, 3, 0x8000000000000},
+ {51, 52, 3, 0x10000000000000},
+ {52, 53, 3, 0x20000000000000},
+ {53, 54, 3, 0x40000000000000},
+ {54, 55, 3, 0x80000000000000},
+ {55, 56, 3, 0x100000000000000},
+ {56, 57, 3, 0x200000000000000},
+ {57, 58, 3, 0x400000000000000},
+ {58, 59, 3, 0x800000000000000},
+ {59, 60, 3, 0x1000000000000000},
+ {60, 61, 3, 0x2000000000000000},
+ {61, 62, 3, 0x4000000000000000},
+ {62, 63, 3, 0x8000000000000000},
+};
+
+#else
+#define MAX_POWER2 30
+
+struct st_features features[] = {
+ {0, 2, 0, 0x1},
+ {1, 3, 0, 0x2},
+ {2, 4, 0, 0x4},
+ {3, 5, 0, 0x8},
+ {4, 6, 0, 0x10},
+ {5, 7, 0, 0x20},
+ {6, 8, 0, 0x40},
+ {7, 9, 0, 0x80},
+ {8, 10, 1, 0x200},
+ {9, 11, 1, 0x400},
+ {10, 12, 1, 0x800},
+ {11, 13, 1, 0x1000},
+ {12, 14, 1, 0x2000},
+ {13, 15, 1, 0x4000},
+ {14, 16, 1, 0x8000},
+ {15, 17, 1, 0x10000},
+ {16, 17, 2, 0x20000},
+ {17, 18, 2, 0x40000},
+ {18, 19, 2, 0x80000},
+ {19, 20, 2, 0x100000},
+ {20, 21, 2, 0x200000},
+ {21, 22, 2, 0x400000},
+ {22, 23, 2, 0x800000},
+ {23, 24, 2, 0x1000000},
+ {24, 25, 2, 0x2000000},
+ {25, 26, 2, 0x4000000},
+ {26, 27, 2, 0x8000000},
+ {27, 28, 2, 0x10000000},
+ {28, 29, 2, 0x20000000},
+ {29, 30, 2, 0x40000000},
+ {30, 31, 2, 0x80000000},
+};
+
+#endif
+
+/* The reserved hash value and its substitution. */
+#define RESERVED_HASH_VAL (~(st_hash_t) 0)
+#define RESERVED_HASH_SUBSTITUTION_VAL ((st_hash_t) 0)
+
+/* Return hash value of KEY for table TAB. */
+static inline st_hash_t
+do_hash(st_data_t key, st_table *tab) {
+ st_index_t h = (st_index_t)(tab->type->hash)(key);
+#if SIZEOF_INT == SIZEOF_VOIDP
+ st_hash_t hash = h;
+#else
+ st_hash_t hash = h;
#endif
- return x + 1;
+
+ /* RESERVED_HASH_VAL is used for a deleted entry. Map it into
+ another value. Such mapping should be extremely rare. */
+ return hash == RESERVED_HASH_VAL ? RESERVED_HASH_SUBSTITUTION_VAL : hash;
}
-static st_index_t
-new_size(st_index_t size)
-{
- st_index_t n;
+/* Power of 2 defining the minimal number of allocated entries. */
+#define MINIMAL_POWER2 3
+
+#if MINIMAL_POWER2 < 2
+#error "MINIMAL_POWER2 should be >= 2"
+#endif
+
+/* If the power2 of the allocated `entries` is less than the following
+ value, don't allocate bins and use a linear search. */
+#define MAX_POWER2_FOR_TABLES_WITHOUT_BINS 3
- if (size && (size & ~(size - 1)) == size) /* already a power-of-two? */
- return size;
+/* Return smallest n >= MINIMAL_POWER2 such 2^n > SIZE. */
+static int
+get_power2(st_index_t size) {
+ unsigned int n;
- n = next_pow2(size);
- if (n > size)
- return n;
+ for (n = 0; size != 0; n++)
+ size >>= 1;
+ if (n <= MAX_POWER2)
+ return n < MINIMAL_POWER2 ? MINIMAL_POWER2 : n;
#ifndef NOT_RUBY
+ /* Ran out of the table entries */
rb_raise(rb_eRuntimeError, "st_table too big");
#endif
- return -1; /* should raise exception */
+ /* should raise exception */
+ return -1;
}
+/* Return value of N-th bin in array BINS of table with bins size
+ index S. */
+static inline st_index_t
+get_bin(st_index_t *bins, int s, st_index_t n) {
+ return (s == 0 ? ((unsigned char *) bins)[n]
+ : s == 1 ? ((unsigned short *) bins)[n]
+ : s == 2 ? ((unsigned int *) bins)[n]
+ : ((st_index_t *) bins)[n]);
+}
+
+/* Set up N-th bin in array BINS of table with bins size index S to
+ value V. */
+static inline void
+set_bin(st_index_t *bins, int s, st_index_t n, st_index_t v) {
+ if (s == 0) ((unsigned char *) bins)[n] = v;
+ else if (s == 1) ((unsigned short *) bins)[n] = v;
+ else if (s == 2) ((unsigned int *) bins)[n] = v;
+ else ((st_index_t *) bins)[n] = v;
+}
+
+/* These macros define reserved values for empty table bin and table
+ bin which contains a deleted entry. We will never use such values
+ for an entry index in bins. */
+#define EMPTY_BIN 0
+#define DELETED_BIN 1
+/* Base of a real entry index in the bins. */
+#define ENTRY_BASE 2
+
+/* Mark I-th bin of table TAB as empty, in other words not
+ corresponding to any entry. */
+#define MARK_BIN_EMPTY(tab, i) (set_bin((tab)->bins, get_size_ind(tab), i, EMPTY_BIN))
+
+/* Values used for not found entry and bin with given
+ characteristics. */
+#define UNDEFINED_ENTRY_IND (~(st_index_t) 0)
+#define UNDEFINED_BIN_IND (~(st_index_t) 0)
+
+/* Mark I-th bin of table TAB as corresponding to a deleted table
+ entry. Update number of entries in the table and number of bins
+ corresponding to deleted entries. */
+#define MARK_BIN_DELETED(tab, i) \
+ do { \
+ st_assert(i != UNDEFINED_BIN_IND); \
+ st_assert(! IND_EMPTY_OR_DELETED_BIN_P(tab, i)); \
+ set_bin((tab)->bins, get_size_ind(tab), i, DELETED_BIN); \
+ } while (0)
+
+/* Macros to check that value B is used empty bins and bins
+ corresponding deleted entries. */
+#define EMPTY_BIN_P(b) ((b) == EMPTY_BIN)
+#define DELETED_BIN_P(b) ((b) == DELETED_BIN)
+#define EMPTY_OR_DELETED_BIN_P(b) ((b) <= DELETED_BIN)
+
+/* Macros to check empty bins and bins corresponding to deleted
+ entries. Bins are given by their index I in table TAB. */
+#define IND_EMPTY_BIN_P(tab, i) (EMPTY_BIN_P(get_bin((tab)->bins, get_size_ind(tab), i)))
+#define IND_DELETED_BIN_P(tab, i) (DELETED_BIN_P(get_bin((tab)->bins, get_size_ind(tab), i)))
+#define IND_EMPTY_OR_DELETED_BIN_P(tab, i) (EMPTY_OR_DELETED_BIN_P(get_bin((tab)->bins, get_size_ind(tab), i)))
+
+/* Macros for marking and checking deleted entries given by their
+ pointer E_PTR. */
+#define MARK_ENTRY_DELETED(e_ptr) ((e_ptr)->hash = RESERVED_HASH_VAL)
+#define DELETED_ENTRY_P(e_ptr) ((e_ptr)->hash == RESERVED_HASH_VAL)
+
+/* Return bin size index of table TAB. */
+static inline st_index_t
+get_size_ind(const st_table *tab) {
+ return tab->size_ind;
+}
+
+/* Return the number of allocated bins of table TAB. */
+static inline st_index_t
+get_bins_num(const st_table *tab) {
+ return 1<<tab->bin_power;
+}
+
+/* Return mask for a bin index in table TAB. */
+static inline st_index_t
+bins_mask(const st_table *tab) {
+ return get_bins_num(tab) - 1;
+}
+
+/* Return the index of table TAB bin corresponding to
+ HASH_VALUE. */
+static inline st_index_t
+hash_bin(st_hash_t hash_value, st_table *tab) {
+ return hash_value & bins_mask(tab);
+}
+
+/* Return the number of allocated entries of table TAB. */
+static inline st_index_t
+get_allocated_entries(const st_table *tab) {
+ return 1<<tab->entry_power;
+}
+
+/* Return size of the allocated bins of table TAB. */
+static inline st_index_t
+bins_size(const st_table *tab) {
+ return features[tab->entry_power].bins_words * sizeof (st_index_t);
+}
+
+/* Mark all bins of table TAB as empty. */
+static void
+initialize_bins(st_table *tab) {
+ memset(tab->bins, 0, bins_size(tab));
+}
+
+/* Make table TAB empty. */
+static void
+make_tab_empty(st_table *tab)
+{
+ tab->num_entries = 0;
+ tab->entries_start = tab->entries_bound = 0;
+ if (tab->bins != NULL)
+ initialize_bins(tab);
+}
+
+#ifdef ST_DEBUG
+/* Check the table T consistency. It can be extremely slow. So use
+ it only for debugging. */
+static void
+st_check(st_table *tab) {
+ st_index_t d, e, i, n, p;
+
+ for (p = get_allocated_entries(tab), i = 0; p > 1; i++, p>>=1)
+ ;
+ p = i;
+ assert(p >= MINIMAL_POWER2);
+ assert(tab->entries_bound <= get_allocated_entries(tab)
+ && tab->entries_start <= tab->entries_bound);
+ n = 0;
+ return;
+ if (tab->entries_bound != 0)
+ for (i = tab->entries_start; i < tab->entries_bound; i++) {
+ assert(tab->entries[i].hash != (st_hash_t) ST_INIT_VAL
+ && tab->entries[i].key != ST_INIT_VAL
+ && tab->entries[i].record != ST_INIT_VAL);
+ if (! DELETED_ENTRY_P(&tab->entries[i]))
+ n++;
+ }
+ assert(n == tab->num_entries);
+ if (tab->bins == NULL)
+ assert(p <= MAX_POWER2_FOR_TABLES_WITHOUT_BINS);
+ else {
+ assert(p > MAX_POWER2_FOR_TABLES_WITHOUT_BINS);
+ for (n = d = i = 0; i < get_bins_num(tab); i++) {
+ assert(get_bin(tab->bins, tab->size_ind, i) != ST_INIT_VAL);
+ if (IND_DELETED_BIN_P(tab, i)) {
+ d++;
+ continue;
+ }
+ else if (IND_EMPTY_BIN_P(tab, i))
+ continue;
+ n++;
+ e = get_bin(tab->bins, tab->size_ind, i) - ENTRY_BASE;
+ assert(tab->entries_start <= e && e < tab->entries_bound);
+ assert(! DELETED_ENTRY_P(&tab->entries[e]));
+ assert(tab->entries[e].hash != (st_hash_t) ST_INIT_VAL
+ && tab->entries[e].key != ST_INIT_VAL
+ && tab->entries[e].record != ST_INIT_VAL);
+ }
+ assert(n == tab->num_entries);
+ assert(n + d < get_bins_num(tab));
+ }
+}
+#endif
+
#ifdef HASH_LOG
#ifdef HAVE_UNISTD_H
#include <unistd.h>
@@ -179,8 +518,13 @@ new_size(st_index_t size)
static struct {
int all, total, num, str, strcase;
} collision;
+
+/* Flag switching off output of package statistics at the end of
+ program. */
static int init_st = 0;
+/* Output overall number of table searches and collisions into a
+ temporary file. */
static void
stat_col(void)
{
@@ -189,1098 +533,1042 @@ stat_col(void)
if (!collision.total) return;
f = fopen((snprintf(fname, sizeof(fname), "/tmp/col%ld", (long)getpid()), fname), "w");
fprintf(f, "collision: %d / %d (%6.2f)\n", collision.all, collision.total,
- ((double)collision.all / (collision.total)) * 100);
+ ((double)collision.all / (collision.total)) * 100);
fprintf(f, "num: %d, str: %d, strcase: %d\n", collision.num, collision.str, collision.strcase);
fclose(f);
}
#endif
-static struct list_head *
-st_head(const st_table *tbl)
-{
- uintptr_t addr = (uintptr_t)&tbl->as.big.private_list_head;
- return (struct list_head *)addr;
-}
-
-st_table*
-st_init_table_with_size(const struct st_hash_type *type, st_index_t size)
-{
- st_table *tbl;
+/* Create and return table with TYPE which can hold at least SIZE
+ entries. The real number of entries which the table can hold is
+ the nearest power of two for SIZE. */
+st_table *
+st_init_table_with_size(const struct st_hash_type *type, st_index_t size) {
+ st_table *tab;
+ int n;
#ifdef HASH_LOG
-# if HASH_LOG+0 < 0
+#if HASH_LOG+0 < 0
{
- const char *e = getenv("ST_HASH_LOG");
- if (!e || !*e) init_st = 1;
+ const char *e = getenv("ST_HASH_LOG");
+ if (!e || !*e) init_st = 1;
}
-# endif
+#endif
if (init_st == 0) {
- init_st = 1;
- atexit(stat_col);
+ init_st = 1;
+ atexit(stat_col);
}
#endif
-
- tbl = st_alloc_table();
- tbl->type = type;
- tbl->num_entries = 0;
- tbl->entries_packed = size <= MAX_PACKED_HASH;
- if (tbl->entries_packed) {
- size = ST_DEFAULT_PACKED_TABLE_SIZE;
- tbl->real_entries = 0;
- }
- else {
- size = new_size(size); /* round up to power-of-two */
- list_head_init(st_head(tbl));
- }
- tbl->num_bins = size;
- tbl->bins = st_alloc_bins(size);
-
- return tbl;
+ n = get_power2(size);
+ tab = (st_table *) malloc(sizeof (st_table));
+ tab->type = type;
+ tab->entry_power = n;
+ tab->bin_power = features[n].bin_power;
+ tab->size_ind = features[n].size_ind;
+ if (n <= MAX_POWER2_FOR_TABLES_WITHOUT_BINS)
+ tab->bins = NULL;
+ else
+ tab->bins = (st_index_t *) malloc(bins_size(tab));
+ tab->entries = (st_table_entry *) malloc(get_allocated_entries(tab)
+ * sizeof(st_table_entry));
+#ifdef ST_DEBUG
+ memset(tab->entries, ST_INIT_VAL_BYTE,
+ get_allocated_entries(tab) * sizeof(st_table_entry));
+ if (tab->bins != NULL)
+ memset(tab->bins, ST_INIT_VAL_BYTE, bins_size(tab));
+#endif
+ make_tab_empty(tab);
+ tab->rebuilds_num = 0;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return tab;
}
-st_table*
-st_init_table(const struct st_hash_type *type)
-{
+/* Create and return table with TYPE which can hold a minimal number
+ of entries (see comments for get_power2). */
+st_table *
+st_init_table(const struct st_hash_type *type) {
return st_init_table_with_size(type, 0);
}
-st_table*
-st_init_numtable(void)
-{
+/* Create and return table which can hold a minimal number of
+ numbers. */
+st_table *
+st_init_numtable(void) {
return st_init_table(&type_numhash);
}
-st_table*
-st_init_numtable_with_size(st_index_t size)
-{
+/* Create and return table which can hold SIZE numbers. */
+st_table *
+st_init_numtable_with_size(st_index_t size) {
return st_init_table_with_size(&type_numhash, size);
}
-st_table*
-st_init_strtable(void)
-{
+/* Create and return table which can hold a minimal number of
+ strings. */
+st_table *
+st_init_strtable(void) {
return st_init_table(&type_strhash);
}
-st_table*
-st_init_strtable_with_size(st_index_t size)
-{
+/* Create and return table which can hold SIZE strings. */
+st_table *
+st_init_strtable_with_size(st_index_t size) {
return st_init_table_with_size(&type_strhash, size);
}
-st_table*
-st_init_strcasetable(void)
-{
+/* Create and return table which can hold a minimal number of strings
+ whose character case is ignored. */
+st_table *
+st_init_strcasetable(void) {
return st_init_table(&type_strcasehash);
}
-st_table*
-st_init_strcasetable_with_size(st_index_t size)
-{
+/* Create and return table which can hold SIZE strings whose character
+ case is ignored. */
+st_table *
+st_init_strcasetable_with_size(st_index_t size) {
return st_init_table_with_size(&type_strcasehash, size);
}
+/* Make table TAB empty. */
void
-st_clear(st_table *table)
-{
- register st_table_entry *ptr = 0, *next;
-
- if (table->entries_packed) {
- table->num_entries = 0;
- table->real_entries = 0;
- return;
- }
-
- list_for_each_safe(st_head(table), ptr, next, olist) {
- /* list_del is not needed */
- st_free_entry(ptr);
- }
- table->num_entries = 0;
- MEMZERO(table->bins, st_table_entry*, table->num_bins);
- list_head_init(st_head(table));
+st_clear(st_table *tab) {
+ make_tab_empty(tab);
+ tab->rebuilds_num++;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
}
+/* Free table TAB space. */
void
-st_free_table(st_table *table)
-{
- st_clear(table);
- st_free_bins(table->bins, table->num_bins);
- st_dealloc_table(table);
+st_free_table(st_table *tab) {
+ if (tab->bins != NULL)
+ free(tab->bins);
+ free(tab->entries);
+ free(tab);
}
+/* Return byte size of memory allocted for table TAB. */
size_t
-st_memsize(const st_table *table)
-{
- if (table->entries_packed) {
- return table->num_bins * sizeof (void *) + sizeof(st_table);
- }
- else {
- return table->num_entries * sizeof(struct st_table_entry) + table->num_bins * sizeof (void *) + sizeof(st_table);
- }
+st_memsize(const st_table *tab) {
+ return(sizeof(st_table)
+ + (tab->bins == NULL ? 0 : bins_size(tab))
+ + get_allocated_entries(tab) * sizeof(st_table_entry));
}
-#define PTR_NOT_EQUAL(table, ptr, hash_val, key) \
-((ptr) != 0 && ((ptr)->hash != (hash_val) || !EQUAL((table), (key), (ptr))))
+static st_index_t
+find_table_entry_ind(st_table *tab, st_hash_t hash_value, st_data_t key);
+
+static st_index_t
+find_table_bin_ind(st_table *tab, st_hash_t hash_value, st_data_t key);
+
+static st_index_t
+find_table_bin_ind_direct(st_table *table, st_hash_t hash_value, st_data_t key);
+
+static st_index_t
+find_table_bin_ptr_and_reserve(st_table *tab, st_hash_t *hash_value,
+ st_data_t key, st_index_t *bin_ind);
#ifdef HASH_LOG
static void
-count_collision(const struct st_hash_type *type)
-{
+count_collision(const struct st_hash_type *type) {
collision.all++;
if (type == &type_numhash) {
- collision.num++;
+ collision.num++;
}
else if (type == &type_strhash) {
- collision.strcase++;
+ collision.strcase++;
}
else if (type == &type_strcasehash) {
- collision.str++;
+ collision.str++;
}
}
-#define COLLISION (collision_check ? count_collision(table->type) : (void)0)
-#define FOUND_ENTRY (collision_check ? collision.total++ : (void)0)
+
+#define COLLISION (collision_check ? count_collision(tab->type) : (void)0)
+#define FOUND_BIN (collision_check ? collision.total++ : (void)0)
#define collision_check 0
#else
#define COLLISION
-#define FOUND_ENTRY
+#define FOUND_BIN
#endif
-#define FIND_ENTRY(table, ptr, hash_val, bin_pos) \
- ((ptr) = find_entry((table), key, (hash_val), ((bin_pos) = hash_pos(hash_val, (table)->num_bins))))
+/* If the number of entries in the table is at least REBUILD_THRESHOLD
+ times less than the entry array length, decrease the table
+ size. */
+#define REBUILD_THRESHOLD 4
-static st_table_entry *
-find_entry(const st_table *table, st_data_t key, st_index_t hash_val,
- st_index_t bin_pos)
-{
- register st_table_entry *ptr = table->bins[bin_pos];
- FOUND_ENTRY;
- if (PTR_NOT_EQUAL(table, ptr, hash_val, key)) {
- COLLISION;
- while (PTR_NOT_EQUAL(table, ptr->next, hash_val, key)) {
- ptr = ptr->next;
- }
- ptr = ptr->next;
- }
- return ptr;
-}
+#if REBUILD_THRESHOLD < 2
+#error "REBUILD_THRESHOLD should be >= 2"
+#endif
-static inline st_index_t
-find_packed_index_from(const st_table *table, st_index_t hash_val,
- st_data_t key, st_index_t i)
-{
- while (i < table->real_entries &&
- (PHASH(table, i) != hash_val || !EQUAL(table, key, &PACKED_ENT(table, i)))) {
- i++;
+/* Rebuild table TAB. Rebuilding removes all deleted bins and entries
+ and can change size of the table entries and bins arrays.
+ Rebuilding is implemented by creation of a new table or by
+ compaction of the existing one. */
+static void
+rebuild_table(st_table *tab) {
+ st_index_t i, ni, bound, size_ind;
+ st_table *new_tab;
+ st_table_entry *entries, *new_entries;
+ st_table_entry *curr_entry_ptr;
+ st_index_t *bins;
+ st_index_t bin_ind;
+
+ st_assert(tab != NULL);
+ bound = tab->entries_bound;
+ entries = tab->entries;
+ if ((2 * tab->num_entries <= get_allocated_entries(tab)
+ && REBUILD_THRESHOLD * tab->num_entries > get_allocated_entries(tab))
+ || tab->num_entries < (1 << MINIMAL_POWER2)) {
+ /* Compaction: */
+ tab->num_entries = 0;
+ if (tab->bins != NULL)
+ initialize_bins(tab);
+ new_tab = tab;
+ new_entries = entries;
}
- return i;
+ else {
+ new_tab = st_init_table_with_size(tab->type,
+ 2 * tab->num_entries - 1);
+ new_entries = new_tab->entries;
+ }
+ ni = 0;
+ bins = new_tab->bins;
+ size_ind = get_size_ind(new_tab);
+ for (i = tab->entries_start; i < bound; i++) {
+ curr_entry_ptr = &entries[i];
+ PREFETCH(entries + i + 1, 0);
+ if (EXPECT(DELETED_ENTRY_P(curr_entry_ptr), 0))
+ continue;
+ if (&new_entries[ni] != curr_entry_ptr)
+ new_entries[ni] = *curr_entry_ptr;
+ if (EXPECT(bins != NULL, 1)) {
+ bin_ind = find_table_bin_ind_direct(new_tab, curr_entry_ptr->hash,
+ curr_entry_ptr->key);
+ st_assert(bin_ind != UNDEFINED_BIN_IND
+ && (tab == new_tab || new_tab->rebuilds_num == 0)
+ && IND_EMPTY_BIN_P(new_tab, bin_ind));
+ set_bin(bins, size_ind, bin_ind, ni + ENTRY_BASE);
+ }
+ new_tab->num_entries++;
+ ni++;
+ }
+ if (new_tab != tab) {
+ tab->entry_power = new_tab->entry_power;
+ tab->bin_power = new_tab->bin_power;
+ tab->size_ind = new_tab->size_ind;
+ st_assert (tab->num_entries == ni && new_tab->num_entries == ni);
+ if (tab->bins != NULL)
+ free(tab->bins);
+ tab->bins = new_tab->bins;
+ free(tab->entries);
+ tab->entries = new_tab->entries;
+ free(new_tab);
+ }
+ tab->entries_start = 0;
+ tab->entries_bound = tab->num_entries;
+ tab->rebuilds_num++;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
}
-static inline st_index_t
-find_packed_index(const st_table *table, st_index_t hash_val, st_data_t key)
-{
- return find_packed_index_from(table, hash_val, key, 0);
-}
+/* Return the next secondary hash index for table TAB using previous
+ index IND and PERTERB. Finally modulo of the function becomes a
+ full *cycle linear congruential generator*, in other words it
+ guarantees traversing all table bins in extreme case.
-int
-st_lookup(st_table *table, register st_data_t key, st_data_t *value)
-{
- st_index_t hash_val;
- register st_table_entry *ptr;
+ According the Hull-Dobell theorem a generator
+ "Xnext = (a*Xprev + c) mod m" is a full cycle generator iff
+ o m and c are relatively prime
+ o a-1 is divisible by all prime factors of m
+ o a-1 is divisible by 4 if m is divisible by 4.
- hash_val = do_hash(key, table);
-
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, key);
- if (i < table->real_entries) {
- if (value != 0) *value = PVAL(table, i);
- return 1;
- }
- return 0;
- }
+ For our case a is 5, c is 1, and m is a power of two. */
+static inline st_index_t
+secondary_hash(st_index_t ind, st_table *tab, st_index_t *perterb) {
+ *perterb >>= 11;
+ ind = (ind << 2) + ind + *perterb + 1;
+ return hash_bin(ind, tab);
+}
- ptr = find_entry(table, key, hash_val, hash_pos(hash_val, table->num_bins));
+/* Find an entry with HASH_VALUE and KEY in TABLE using a linear
+ search. Return the index of the found entry in array `entries`.
+ If it is not found, return UNDEFINED_ENTRY_IND. */
+static inline st_index_t
+find_entry(st_table *tab, st_hash_t hash_value, st_data_t key) {
+ st_index_t i, bound;
+ st_table_entry *entries;
- if (ptr == 0) {
- return 0;
- }
- else {
- if (value != 0) *value = ptr->record;
- return 1;
+ bound = tab->entries_bound;
+ entries = tab->entries;
+ for (i = tab->entries_start; i < bound; i++) {
+ if (PTR_EQUAL(tab, &entries[i], hash_value, key))
+ return i;
}
+ return UNDEFINED_ENTRY_IND;
}
-int
-st_get_key(st_table *table, register st_data_t key, st_data_t *result)
-{
- st_index_t hash_val;
- register st_table_entry *ptr;
-
- hash_val = do_hash(key, table);
+/* Use the quadratic probing. The method has a better data locality
+ but more collisions than the current approach. In average it
+ results in a bit slower search. */
+/*#define QUADRATIC_PROBE*/
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, key);
- if (i < table->real_entries) {
- if (result != 0) *result = PKEY(table, i);
- return 1;
- }
- return 0;
- }
-
- ptr = find_entry(table, key, hash_val, hash_pos(hash_val, table->num_bins));
+/* Return index of entry with HASH_VALUE and KEY in table TAB. If
+ there is no such entry, return UNDEFINED_ENTRY_IND. */
+static st_index_t
+find_table_entry_ind(st_table *tab, st_hash_t hash_value, st_data_t key) {
+ st_index_t ind;
+#ifdef QUADRATIC_PROBE
+ st_index_t d;
+#else
+ st_index_t peterb;
+#endif
+ st_index_t bin;
+ st_table_entry *entries = tab->entries;
- if (ptr == 0) {
- return 0;
- }
- else {
- if (result != 0) *result = ptr->key;
- return 1;
+ st_assert(tab != NULL && tab->bins != NULL);
+ ind = hash_bin(hash_value, tab);
+#ifdef QUADRATIC_PROBE
+ d = 1;
+#else
+ peterb = hash_value;
+#endif
+ FOUND_BIN;
+ for (;;) {
+ bin = get_bin(tab->bins, get_size_ind(tab), ind);
+ if (! EMPTY_OR_DELETED_BIN_P(bin)
+ && PTR_EQUAL(tab, &entries[bin - ENTRY_BASE], hash_value, key))
+ break;
+ else if (EMPTY_BIN_P(bin))
+ return UNDEFINED_ENTRY_IND;
+#ifdef QUADRATIC_PROBE
+ ind = hash_bin(ind + d, tab);
+ d++;
+#else
+ ind = secondary_hash(ind, tab, &peterb);
+#endif
+ COLLISION;
}
+ return bin;
}
-static inline st_table_entry *
-new_entry(st_table * table, st_data_t key, st_data_t value,
- st_index_t hash_val, register st_index_t bin_pos)
-{
- register st_table_entry *entry = st_alloc_entry();
-
- entry->next = table->bins[bin_pos];
- table->bins[bin_pos] = entry;
- entry->hash = hash_val;
- entry->key = key;
- entry->record = value;
-
- return entry;
-}
+/* Find and return index of table TAB bin corresponding to an entry
+ with HASH_VALUE and KEY. If there is no such bin, return
+ UNDEFINED_BIN_IND. */
+static st_index_t
+find_table_bin_ind(st_table *tab, st_hash_t hash_value, st_data_t key) {
+ st_index_t ind;
+#ifdef QUADRATIC_PROBE
+ st_index_t d;
+#else
+ st_index_t peterb;
+#endif
+ st_index_t bin;
+ st_table_entry *entries = tab->entries;
-static inline void
-add_direct(st_table *table, st_data_t key, st_data_t value,
- st_index_t hash_val, register st_index_t bin_pos)
-{
- register st_table_entry *entry;
- if (table->num_entries > ST_DEFAULT_MAX_DENSITY * table->num_bins) {
- rehash(table);
- bin_pos = hash_pos(hash_val, table->num_bins);
+ st_assert(tab != NULL && tab->bins != NULL);
+ ind = hash_bin(hash_value, tab);
+#ifdef QUADRATIC_PROBE
+ d = 1;
+#else
+ peterb = hash_value;
+#endif
+ FOUND_BIN;
+ for (;;) {
+ bin = get_bin(tab->bins, get_size_ind(tab), ind);
+ if (! EMPTY_OR_DELETED_BIN_P(bin)
+ && PTR_EQUAL(tab, &entries[bin - ENTRY_BASE], hash_value, key))
+ break;
+ else if (EMPTY_BIN_P(bin))
+ return UNDEFINED_BIN_IND;
+#ifdef QUADRATIC_PROBE
+ ind = hash_bin(ind + d, tab);
+ d++;
+#else
+ ind = secondary_hash(ind, tab, &peterb);
+#endif
+ COLLISION;
}
-
- entry = new_entry(table, key, value, hash_val, bin_pos);
- list_add_tail(st_head(table), &entry->olist);
- table->num_entries++;
+ return ind;
}
-static void
-unpack_entries(register st_table *table)
-{
- st_index_t i;
- st_packed_entry packed_bins[MAX_PACKED_HASH];
- register st_table_entry *entry;
- st_table tmp_table = *table;
-
- MEMCPY(packed_bins, PACKED_BINS(table), st_packed_entry, MAX_PACKED_HASH);
- table->as.packed.entries = packed_bins;
- tmp_table.entries_packed = 0;
-#if ST_DEFAULT_INIT_TABLE_SIZE == ST_DEFAULT_PACKED_TABLE_SIZE
- MEMZERO(tmp_table.bins, st_table_entry*, tmp_table.num_bins);
+/* Find and return index of table TAB bin corresponding to an entry
+ with HASH_VALUE and KEY. The entry should be in the table
+ already. */
+static st_index_t
+find_table_bin_ind_direct(st_table *tab, st_hash_t hash_value, st_data_t key) {
+ st_index_t ind;
+#ifdef QUADRATIC_PROBE
+ st_index_t d;
#else
- tmp_table.bins = st_realloc_bins(tmp_table.bins, ST_DEFAULT_INIT_TABLE_SIZE, tmp_table.num_bins);
- tmp_table.num_bins = ST_DEFAULT_INIT_TABLE_SIZE;
+ st_index_t peterb;
#endif
+ st_index_t bin;
+ st_table_entry *entries = tab->entries;
- /*
- * order is important here, we need to keep the original table
- * walkable during GC (GC may be triggered by new_entry call)
- */
- i = 0;
- list_head_init(st_head(&tmp_table));
- do {
- st_data_t key = packed_bins[i].key;
- st_data_t val = packed_bins[i].val;
- st_index_t hash = packed_bins[i].hash;
- entry = new_entry(&tmp_table, key, val, hash,
- hash_pos(hash, ST_DEFAULT_INIT_TABLE_SIZE));
- list_add_tail(st_head(&tmp_table), &entry->olist);
- } while (++i < MAX_PACKED_HASH);
- *table = tmp_table;
- list_head_init(st_head(table));
- list_append_list(st_head(table), st_head(&tmp_table));
+ st_assert(tab != NULL && tab->bins != NULL);
+ ind = hash_bin(hash_value, tab);
+#ifdef QUADRATIC_PROBE
+ d = 1;
+#else
+ peterb = hash_value;
+#endif
+ FOUND_BIN;
+ for (;;) {
+ bin = get_bin(tab->bins, get_size_ind(tab), ind);
+ if (EMPTY_OR_DELETED_BIN_P(bin))
+ return ind;
+ st_assert (! PTR_EQUAL(tab, &entries[bin - ENTRY_BASE], hash_value, key));
+#ifdef QUADRATIC_PROBE
+ ind = hash_bin(ind + d, tab);
+ d++;
+#else
+ ind = secondary_hash(ind, tab, &peterb);
+#endif
+ COLLISION;
+ }
}
-static void
-add_packed_direct(st_table *table, st_data_t key, st_data_t value, st_index_t hash_val)
-{
- if (table->real_entries < MAX_PACKED_HASH) {
- st_index_t i = table->real_entries++;
- PKEY_SET(table, i, key);
- PVAL_SET(table, i, value);
- PHASH_SET(table, i, hash_val);
- table->num_entries++;
- }
- else {
- unpack_entries(table);
- add_direct(table, key, value, hash_val, hash_pos(hash_val, table->num_bins));
+/* Return index of table TAB bin for HASH_VALUE and KEY through
+ BIN_IND and the pointed value as the function result. Reserve the
+ bin for inclusion of the corresponding entry into the table if it
+ is not there yet. We always find such bin as bins array length is
+ bigger entries array. Although we can reuse a deleted bin, the
+ result bin value is always empty if the table has no entry with
+ KEY. Return the entries array index of the found entry or
+ UNDEFINED_ENTRY_IND if it is not found. */
+static st_index_t
+find_table_bin_ptr_and_reserve(st_table *tab, st_hash_t *hash_value,
+ st_data_t key, st_index_t *bin_ind) {
+ st_index_t ind;
+ st_hash_t curr_hash_value = *hash_value;
+#ifdef QUADRATIC_PROBE
+ st_index_t d;
+#else
+ st_index_t peterb;
+#endif
+ st_index_t entry_index;
+ st_index_t first_deleted_bin_ind;
+ st_table_entry *entries;
+
+ st_assert(tab != NULL && tab->bins != NULL
+ && tab->entries_bound <= get_allocated_entries(tab)
+ && tab->entries_start <= tab->entries_bound);
+ ind = hash_bin(curr_hash_value, tab);
+#ifdef QUADRATIC_PROBE
+ d = 1;
+#else
+ peterb = curr_hash_value;
+#endif
+ FOUND_BIN;
+ first_deleted_bin_ind = UNDEFINED_BIN_IND;
+ entries = tab->entries;
+ for (;;) {
+ entry_index = get_bin(tab->bins, get_size_ind(tab), ind);
+ if (EMPTY_BIN_P(entry_index)) {
+ tab->num_entries++;
+ entry_index = UNDEFINED_ENTRY_IND;
+ if (first_deleted_bin_ind != UNDEFINED_BIN_IND) {
+ /* We can reuse bin of a deleted entry. */
+ ind = first_deleted_bin_ind;
+ MARK_BIN_EMPTY(tab, ind);
+ }
+ break;
+ } else if (! DELETED_BIN_P(entry_index)) {
+ if (PTR_EQUAL(tab, &entries[entry_index - ENTRY_BASE], curr_hash_value, key))
+ break;
+ } else if (first_deleted_bin_ind == UNDEFINED_BIN_IND)
+ first_deleted_bin_ind = ind;
+#ifdef QUADRATIC_PROBE
+ ind = hash_bin(ind + d, tab);
+ d++;
+#else
+ ind = secondary_hash(ind, tab, &peterb);
+#endif
+ COLLISION;
}
+ *bin_ind = ind;
+ return entry_index;
}
-
+/* Find an entry with KEY in table TAB. Return non-zero if we found
+ it. Set up *RECORD to the found entry record. */
int
-st_insert(register st_table *table, register st_data_t key, st_data_t value)
-{
- st_index_t hash_val;
- register st_index_t bin_pos;
- register st_table_entry *ptr;
+st_lookup(st_table *tab, st_data_t key, st_data_t *value) {
+ st_index_t bin;
+ st_hash_t hash = do_hash(key, tab);
- hash_val = do_hash(key, table);
-
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, key);
- if (i < table->real_entries) {
- PVAL_SET(table, i, value);
- return 1;
- }
- add_packed_direct(table, key, value, hash_val);
- return 0;
- }
-
- FIND_ENTRY(table, ptr, hash_val, bin_pos);
-
- if (ptr == 0) {
- add_direct(table, key, value, hash_val, bin_pos);
- return 0;
- }
- else {
- ptr->record = value;
- return 1;
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash, key);
+ if (bin == UNDEFINED_ENTRY_IND)
+ return 0;
+ } else {
+ bin = find_table_entry_ind(tab, hash, key);
+ if (bin == UNDEFINED_ENTRY_IND)
+ return 0;
+ bin -= ENTRY_BASE;
}
+ if (value != 0)
+ *value = tab->entries[bin].record;
+ return 1;
}
+/* Find an entry with KEY in table TAB. Return non-zero if we found
+ it. Set up *RESULT to the found table entry key. */
int
-st_insert2(register st_table *table, register st_data_t key, st_data_t value,
- st_data_t (*func)(st_data_t))
-{
- st_index_t hash_val;
- register st_index_t bin_pos;
- register st_table_entry *ptr;
-
- hash_val = do_hash(key, table);
+st_get_key(st_table *tab, st_data_t key, st_data_t *result) {
+ st_index_t bin;
+ st_hash_t hash = do_hash(key, tab);
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, key);
- if (i < table->real_entries) {
- PVAL_SET(table, i, value);
- return 1;
- }
- key = (*func)(key);
- add_packed_direct(table, key, value, hash_val);
- return 0;
- }
-
- FIND_ENTRY(table, ptr, hash_val, bin_pos);
-
- if (ptr == 0) {
- key = (*func)(key);
- add_direct(table, key, value, hash_val, bin_pos);
- return 0;
- }
- else {
- ptr->record = value;
- return 1;
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash, key);
+ if (bin == UNDEFINED_ENTRY_IND)
+ return 0;
+ } else {
+ bin = find_table_entry_ind(tab, hash, key);
+ if (bin == UNDEFINED_ENTRY_IND)
+ return 0;
+ bin -= ENTRY_BASE;
}
+ if (result != 0)
+ *result = tab->entries[bin].key;
+ return 1;
}
-void
-st_add_direct(st_table *table, st_data_t key, st_data_t value)
-{
- st_index_t hash_val;
-
- hash_val = do_hash(key, table);
- if (table->entries_packed) {
- add_packed_direct(table, key, value, hash_val);
- return;
- }
+/* Check the table and rebuild it if it is necessary. */
+static inline void
+rebuild_table_if_necessary (st_table *tab) {
+ st_index_t bound = tab->entries_bound;
- add_direct(table, key, value, hash_val, hash_pos(hash_val, table->num_bins));
+ if (bound == get_allocated_entries(tab))
+ rebuild_table(tab);
+ st_assert(tab->entries_bound < get_allocated_entries(tab));
}
-static void
-rehash(register st_table *table)
-{
- register st_table_entry *ptr = 0, **new_bins;
- st_index_t new_num_bins, hash_val;
-
- new_num_bins = new_size(table->num_bins+1);
- new_bins = st_realloc_bins(table->bins, new_num_bins, table->num_bins);
- table->num_bins = new_num_bins;
- table->bins = new_bins;
-
- list_for_each(st_head(table), ptr, olist) {
- hash_val = hash_pos(ptr->hash, new_num_bins);
- ptr->next = new_bins[hash_val];
- new_bins[hash_val] = ptr;
+/* Insert (KEY, VALUE) into table TAB and return zero. If there is
+ already entry with KEY in the table, return nonzero and and update
+ the value of the found entry. */
+int
+st_insert(st_table *tab, st_data_t key, st_data_t value) {
+ st_table_entry *entry;
+ st_index_t bin;
+ st_index_t ind;
+ st_hash_t hash_value;
+ st_index_t bin_ind;
+ int new_p;
+
+ rebuild_table_if_necessary(tab);
+ hash_value = do_hash(key, tab);
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash_value, key);
+ new_p = bin == UNDEFINED_ENTRY_IND;
+ if (new_p)
+ tab->num_entries++;
+ bin_ind = UNDEFINED_BIN_IND;
+ } else {
+ bin = find_table_bin_ptr_and_reserve(tab, &hash_value,
+ key, &bin_ind);
+ new_p = bin == UNDEFINED_ENTRY_IND;
+ bin -= ENTRY_BASE;
+ }
+ if (new_p) {
+ st_assert(tab->entries_bound < get_allocated_entries(tab));
+ ind = tab->entries_bound++;
+ entry = &tab->entries[ind];
+ entry->hash = hash_value;
+ entry->key = key;
+ entry->record = value;
+ if (bin_ind != UNDEFINED_BIN_IND)
+ set_bin(tab->bins, get_size_ind(tab), bin_ind, ind + ENTRY_BASE);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 0;
}
+ tab->entries[bin].record = value;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 1;
}
-st_table*
-st_copy(st_table *old_table)
-{
- st_table *new_table;
- st_table_entry *ptr = 0, *entry;
- st_index_t num_bins = old_table->num_bins;
-
- new_table = st_alloc_table();
- if (new_table == 0) {
- return 0;
- }
-
- *new_table = *old_table;
- new_table->bins = st_alloc_bins(num_bins);
-
- if (new_table->bins == 0) {
- st_dealloc_table(new_table);
- return 0;
- }
-
- if (old_table->entries_packed) {
- MEMCPY(new_table->bins, old_table->bins, st_table_entry*, old_table->num_bins);
- return new_table;
- }
-
- list_head_init(st_head(new_table));
-
- list_for_each(st_head(old_table), ptr, olist) {
- entry = new_entry(new_table, ptr->key, ptr->record, ptr->hash,
- hash_pos(ptr->hash, num_bins));
- list_add_tail(st_head(new_table), &entry->olist);
- }
-
- return new_table;
+/* Insert (KEY, VALUE, HASH) into table TAB. The table should not have
+ entry with KEY before the insertion. */
+static inline void
+st_add_direct_with_hash(st_table *tab,
+ st_data_t key, st_data_t value, st_hash_t hash) {
+ st_table_entry *entry;
+ st_index_t ind;
+ st_index_t bin_ind;
+
+ rebuild_table_if_necessary(tab);
+ ind = tab->entries_bound++;
+ entry = &tab->entries[ind];
+ entry->hash = hash;
+ entry->key = key;
+ entry->record = value;
+ tab->num_entries++;
+ if (tab->bins != NULL) {
+ bin_ind = find_table_bin_ind_direct(tab, hash, key);
+ st_assert (bin_ind != UNDEFINED_BIN_IND);
+ set_bin(tab->bins, get_size_ind(tab), bin_ind, ind + ENTRY_BASE);
+ }
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
}
-static inline void
-remove_entry(st_table *table, st_table_entry *ptr)
-{
- list_del(&ptr->olist);
- table->num_entries--;
+/* Insert (KEY, VALUE) into table TAB. The table should not have
+ entry with KEY before the insertion. */
+void
+st_add_direct(st_table *tab, st_data_t key, st_data_t value) {
+ st_hash_t hash_value;
+
+ hash_value = do_hash(key, tab);
+ st_add_direct_with_hash(tab, key, value, hash_value);
}
+/* Insert (FUNC(KEY), VALUE) into table TAB and return zero. If
+ there is already entry with KEY in the table, return nonzero and
+ and update the value of the found entry. */
int
-st_delete(register st_table *table, register st_data_t *key, st_data_t *value)
-{
- st_index_t hash_val;
- st_table_entry **prev;
- register st_table_entry *ptr;
-
- hash_val = do_hash(*key, table);
-
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, *key);
- if (i < table->real_entries) {
- if (value != 0) *value = PVAL(table, i);
- *key = PKEY(table, i);
- remove_packed_entry(table, i);
- return 1;
- }
- if (value != 0) *value = 0;
+st_insert2(st_table *tab, st_data_t key, st_data_t value,
+ st_data_t (*func)(st_data_t)) {
+ st_table_entry *entry;
+ st_index_t bin;
+ st_index_t ind, check;
+ st_hash_t hash_value;
+ st_index_t bin_ind;
+ int new_p;
+
+ rebuild_table_if_necessary (tab);
+ hash_value = do_hash(key, tab);
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash_value, key);
+ new_p = bin == UNDEFINED_ENTRY_IND;
+ bin_ind = UNDEFINED_BIN_IND;
+ } else {
+ bin = find_table_bin_ptr_and_reserve(tab, &hash_value,
+ key, &bin_ind);
+ new_p = bin == UNDEFINED_ENTRY_IND;
+ bin -= ENTRY_BASE;
+ }
+ if (new_p) {
+ st_assert(tab->entries_bound < get_allocated_entries(tab));
+ check = tab->rebuilds_num;
+ key = (*func)(key);
+ st_assert(check == tab->rebuilds_num
+ && do_hash(key, tab) == hash_value);
+ ind = tab->entries_bound++;
+ entry = &tab->entries[ind];
+ entry->hash = hash_value;
+ entry->key = key;
+ entry->record = value;
+ if (bin_ind != UNDEFINED_BIN_IND)
+ set_bin(tab->bins, get_size_ind(tab), bin_ind, ind + ENTRY_BASE);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
return 0;
}
+ tab->entries[bin].record = value;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 1;
+}
- prev = &table->bins[hash_pos(hash_val, table->num_bins)];
- for (;(ptr = *prev) != 0; prev = &ptr->next) {
- if (EQUAL(table, *key, ptr)) {
- *prev = ptr->next;
- remove_entry(table, ptr);
- if (value != 0) *value = ptr->record;
- *key = ptr->key;
- st_free_entry(ptr);
- return 1;
- }
- }
+/* Create and return a copy of table OLD_TAB. */
+st_table *
+st_copy(st_table *old_tab) {
+ st_table *new_tab;
+
+ new_tab = (st_table *) malloc(sizeof(st_table));
+ *new_tab = *old_tab;
+ if (old_tab->bins == NULL)
+ new_tab->bins = NULL;
+ else
+ new_tab->bins = (st_index_t *) malloc(bins_size(old_tab));
+ new_tab->entries = (st_table_entry *) malloc(get_allocated_entries(old_tab)
+ * sizeof(st_table_entry));
+ MEMCPY(new_tab->entries, old_tab->entries, st_table_entry,
+ get_allocated_entries(old_tab));
+ if (old_tab->bins != NULL)
+ MEMCPY(new_tab->bins, old_tab->bins, char, bins_size(old_tab));
+#ifdef ST_DEBUG
+ st_check(new_tab);
+#endif
+ return new_tab;
+}
- if (value != 0) *value = 0;
- return 0;
+/* Update the entries start of table TAB after removing an entry
+ with index N in the array entries. */
+static inline void
+update_range_for_deleted(st_table *tab, st_index_t n) {
+ /* Do not update entries_bound here. Otherwise, we can fill all
+ bins by deleted entry value before rebuilding the table. */
+ if (tab->entries_start == n)
+ tab->entries_start = n + 1;
}
-int
-st_delete_safe(register st_table *table, register st_data_t *key, st_data_t *value, st_data_t never)
+/* Delete entry with KEY from table TAB, set up *VALUE (unless
+ VALUE is zero) from deleted table entry, and return non-zero. If
+ there is no entry with KEY in the table, clear *VALUE (unless VALUE
+ is zero), and return zero. */
+static int
+st_general_delete(st_table *tab, st_data_t *key, st_data_t *value)
{
- st_index_t hash_val;
- register st_table_entry *ptr;
-
- hash_val = do_hash(*key, table);
-
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, *key);
- if (i < table->real_entries) {
- if (value != 0) *value = PVAL(table, i);
- *key = PKEY(table, i);
- remove_safe_packed_entry(table, i, never);
- return 1;
+ st_table_entry *entry;
+ st_index_t bin;
+ st_index_t bin_ind;
+ st_hash_t hash;
+
+ st_assert(tab != NULL);
+ hash = do_hash(*key, tab);
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash, *key);
+ if (bin == UNDEFINED_ENTRY_IND) {
+ if (value != 0) *value = 0;
+ return 0;
}
- if (value != 0) *value = 0;
- return 0;
- }
-
- ptr = table->bins[hash_pos(hash_val, table->num_bins)];
-
- for (; ptr != 0; ptr = ptr->next) {
- if ((ptr->key != never) && EQUAL(table, *key, ptr)) {
- remove_entry(table, ptr);
- *key = ptr->key;
- if (value != 0) *value = ptr->record;
- ptr->key = ptr->record = never;
- return 1;
+ } else {
+ bin_ind = find_table_bin_ind(tab, hash, *key);
+ if (bin_ind == UNDEFINED_BIN_IND) {
+ if (value != 0) *value = 0;
+ return 0;
}
- }
-
- if (value != 0) *value = 0;
- return 0;
+ bin = get_bin(tab->bins, get_size_ind(tab), bin_ind) - ENTRY_BASE;
+ MARK_BIN_DELETED(tab, bin_ind);
+ }
+ entry = &tab->entries[bin];
+ *key = entry->key;
+ if (value != 0) *value = entry->record;
+ MARK_ENTRY_DELETED(entry);
+ tab->num_entries--;
+ update_range_for_deleted(tab, bin);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 1;
}
int
-st_shift(register st_table *table, register st_data_t *key, st_data_t *value)
-{
- st_table_entry *old;
- st_table_entry **prev;
- register st_table_entry *ptr;
-
- if (table->num_entries == 0) {
- if (value != 0) *value = 0;
- return 0;
- }
-
- if (table->entries_packed) {
- if (value != 0) *value = PVAL(table, 0);
- *key = PKEY(table, 0);
- remove_packed_entry(table, 0);
- return 1;
- }
-
- old = list_pop(st_head(table), st_table_entry, olist);
- table->num_entries--;
- prev = &table->bins[hash_pos(old->hash, table->num_bins)];
- while ((ptr = *prev) != old) prev = &ptr->next;
- *prev = ptr->next;
- if (value != 0) *value = ptr->record;
- *key = ptr->key;
- st_free_entry(ptr);
- return 1;
+st_delete(st_table *tab, st_data_t *key, st_data_t *value) {
+ return st_general_delete(tab, key, value);
}
-void
-st_cleanup_safe(st_table *table, st_data_t never)
-{
- st_table_entry *ptr, **last, *tmp;
- st_index_t i;
-
- if (table->entries_packed) {
- st_index_t i = 0, j = 0;
- while (PKEY(table, i) != never) {
- if (i++ == table->real_entries) return;
- }
- for (j = i; ++i < table->real_entries;) {
- if (PKEY(table, i) == never) continue;
- PACKED_ENT(table, j) = PACKED_ENT(table, i);
- j++;
- }
- table->real_entries = j;
- /* table->num_entries really should be equal j at this moment, but let set it anyway */
- table->num_entries = j;
- return;
- }
-
- for (i = 0; i < table->num_bins; i++) {
- ptr = *(last = &table->bins[i]);
- while (ptr != 0) {
- if (ptr->key == never) {
- tmp = ptr;
- *last = ptr = ptr->next;
- st_free_entry(tmp);
- }
- else {
- ptr = *(last = &ptr->next);
- }
- }
- }
+/* The function and other functions with suffix '_safe' or '_check'
+ are originated from the previous implementation of the hash tables.
+ It was necessary for correct deleting entries during traversing
+ tables. The current implementation permits deletion during
+ traversing without a specific way to do this. */
+int
+st_delete_safe(st_table *tab, st_data_t *key, st_data_t *value,
+ st_data_t never ATTRIBUTE_UNUSED) {
+ return st_general_delete(tab, key, value);
}
+/* If table TAB is empty, clear *VALUE (unless VALUE is zero), and
+ return zero. Otherwise, remove the first entry in the table.
+ Return its key through KEY and its record through VALUE (unless
+ VALUE is zero). */
int
-st_update(st_table *table, st_data_t key, st_update_callback_func *func, st_data_t arg)
-{
- st_index_t hash_val, bin_pos;
- register st_table_entry *ptr, **last, *tmp;
- st_data_t value = 0, old_key;
- int retval, existing = 0;
-
- hash_val = do_hash(key, table);
-
- if (table->entries_packed) {
- st_index_t i = find_packed_index(table, hash_val, key);
- if (i < table->real_entries) {
- key = PKEY(table, i);
- value = PVAL(table, i);
- existing = 1;
- }
- {
- old_key = key;
- retval = (*func)(&key, &value, arg, existing);
- if (!table->entries_packed) {
- FIND_ENTRY(table, ptr, hash_val, bin_pos);
- goto unpacked;
- }
- switch (retval) {
- case ST_CONTINUE:
- if (!existing) {
- add_packed_direct(table, key, value, hash_val);
- break;
- }
- if (old_key != key) {
- PKEY(table, i) = key;
- }
- PVAL_SET(table, i, value);
- break;
- case ST_DELETE:
- if (!existing) break;
- remove_packed_entry(table, i);
+st_shift(st_table *tab, st_data_t *key, st_data_t *value) {
+ st_index_t i, bound;
+ st_index_t bin;
+ st_table_entry *entries, *curr_entry_ptr;
+ st_index_t bin_ind;
+
+ entries = tab->entries;
+ bound = tab->entries_bound;
+ for (i = tab->entries_start; i < bound; i++) {
+ curr_entry_ptr = &entries[i];
+ if (! DELETED_ENTRY_P(curr_entry_ptr)) {
+ if (value != 0) *value = curr_entry_ptr->record;
+ *key = curr_entry_ptr->key;
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, curr_entry_ptr->hash, curr_entry_ptr->key);
+ st_assert(bin != UNDEFINED_ENTRY_IND
+ && &entries[bin] == curr_entry_ptr);
+ } else {
+ bin_ind = find_table_bin_ind(tab, curr_entry_ptr->hash,
+ curr_entry_ptr->key);
+ st_assert(bin_ind != UNDEFINED_BIN_IND
+ && &entries[get_bin(tab->bins, get_size_ind(tab), bin_ind)
+ - ENTRY_BASE] == curr_entry_ptr);
+ MARK_BIN_DELETED(tab, bin_ind);
}
+ MARK_ENTRY_DELETED(curr_entry_ptr);
+ tab->num_entries--;
+ update_range_for_deleted(tab, i);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 1;
}
- return existing;
}
+ st_assert(tab->num_entries == 0);
+ tab->entries_start = tab->entries_bound = 0;
+ if (value != 0) *value = 0;
+ return 0;
+}
- FIND_ENTRY(table, ptr, hash_val, bin_pos);
-
- if (ptr != 0) {
- key = ptr->key;
- value = ptr->record;
- existing = 1;
- }
- {
- old_key = key;
- retval = (*func)(&key, &value, arg, existing);
- unpacked:
- switch (retval) {
- case ST_CONTINUE:
- if (!existing) {
- add_direct(table, key, value, hash_val, hash_pos(hash_val, table->num_bins));
- break;
- }
- if (old_key != key) {
- ptr->key = key;
- }
- ptr->record = value;
- break;
- case ST_DELETE:
- if (!existing) break;
- last = &table->bins[bin_pos];
- for (; (tmp = *last) != 0; last = &tmp->next) {
- if (ptr == tmp) {
- *last = ptr->next;
- remove_entry(table, ptr);
- st_free_entry(ptr);
- break;
- }
- }
- break;
- }
- return existing;
- }
+/* See comments for function st_delete_safe. */
+void
+st_cleanup_safe(st_table *tab ATTRIBUTE_UNUSED,
+ st_data_t never ATTRIBUTE_UNUSED) {
}
+/* Find entry with KEY in table TAB, call FUNC with the key and the
+ value of the found entry, and non-zero as the 3rd argument. If the
+ entry is not found, call FUNC with KEY, and 2 zero arguments. If
+ the call returns ST_CONTINUE, the table will have an entry with key
+ and value returned by FUNC through the 1st and 2nd parameters. If
+ the call of FUNC returns ST_DELETE, the table will not have entry
+ with KEY. The function returns flag of that the entry with KEY was
+ in the table before the call. */
int
-st_foreach_check(st_table *table, int (*func)(ANYARGS), st_data_t arg, st_data_t never)
-{
- st_table_entry *ptr = 0, **last, *tmp, *next;
- struct list_head *head;
- enum st_retval retval;
- st_index_t i;
-
- if (table->entries_packed) {
- for (i = 0; i < table->real_entries; i++) {
- st_data_t key, val;
- st_index_t hash;
- key = PKEY(table, i);
- val = PVAL(table, i);
- hash = PHASH(table, i);
- if (key == never) continue;
- retval = (*func)(key, val, arg, 0);
- if (!table->entries_packed) {
- FIND_ENTRY(table, ptr, hash, i);
- if (retval == ST_CHECK) {
- if (!ptr) goto deleted;
- }
- if (table->num_entries == 0) return 0;
- head = st_head(table);
- next = list_entry(ptr->olist.next, st_table_entry, olist);
- goto unpacked;
- }
- switch (retval) {
- case ST_CHECK: /* check if hash is modified during iteration */
- if (PHASH(table, i) == 0 && PKEY(table, i) == never) {
- break;
- }
- i = find_packed_index_from(table, hash, key, i);
- if (i >= table->real_entries) {
- i = find_packed_index(table, hash, key);
- if (i >= table->real_entries) goto deleted;
- }
- /* fall through */
- case ST_CONTINUE:
- break;
- case ST_STOP:
- return 0;
- case ST_DELETE:
- remove_safe_packed_entry(table, i, never);
- break;
- }
+st_update(st_table *tab, st_data_t key,
+ st_update_callback_func *func, st_data_t arg) {
+ st_table_entry *entry = NULL; /* to avoid uninitialized value warning */
+ st_index_t bin = 0; /* Ditto */
+ st_table_entry *entries;
+ st_index_t bin_ind;
+ st_data_t value = 0, old_key;
+ st_index_t check;
+ int retval, existing;
+ st_hash_t hash = do_hash(key, tab);
+
+ entries = tab->entries;
+ if (tab->bins == NULL) {
+ bin = find_entry(tab, hash, key);
+ existing = bin != UNDEFINED_ENTRY_IND;
+ entry = &entries[bin];
+ bin_ind = UNDEFINED_BIN_IND;
+ } else {
+ bin_ind = find_table_bin_ind(tab, hash, key);
+ existing = bin_ind != UNDEFINED_BIN_IND;
+ if (existing) {
+ bin = get_bin(tab->bins, get_size_ind(tab), bin_ind) - ENTRY_BASE;
+ entry = &entries[bin];
}
- return 0;
}
-
- head = st_head(table);
- list_for_each_safe(head, ptr, next, olist) {
- if (ptr->key != never) {
- i = hash_pos(ptr->hash, table->num_bins);
- retval = (*func)(ptr->key, ptr->record, arg, 0);
- unpacked:
- switch (retval) {
- case ST_CHECK: /* check if hash is modified during iteration */
- for (tmp = table->bins[i]; tmp != ptr; tmp = tmp->next) {
- if (!tmp) {
- deleted:
- /* call func with error notice */
- retval = (*func)(0, 0, arg, 1);
- return 1;
- }
- }
- /* fall through */
- case ST_CONTINUE:
- break;
- case ST_STOP:
- return 0;
- case ST_DELETE:
- last = &table->bins[hash_pos(ptr->hash, table->num_bins)];
- for (; (tmp = *last) != 0; last = &tmp->next) {
- if (ptr == tmp) {
- remove_entry(table, ptr);
- ptr->key = ptr->record = never;
- ptr->hash = 0;
- break;
- }
- }
- if (table->num_entries == 0) return 0;
- }
- }
+ if (existing) {
+ key = entry->key;
+ value = entry->record;
+ }
+ old_key = key;
+ check = tab->rebuilds_num;
+ retval = (*func)(&key, &value, arg, existing);
+ st_assert(check == tab->rebuilds_num);
+ switch (retval) {
+ case ST_CONTINUE:
+ if (! existing) {
+ st_add_direct_with_hash(tab, key, value, hash);
+ break;
+ }
+ if (old_key != key) {
+ entry->key = key;
+ }
+ entry->record = value;
+ break;
+ case ST_DELETE:
+ if (existing) {
+ if (bin_ind != UNDEFINED_BIN_IND)
+ MARK_BIN_DELETED(tab, bin_ind);
+ MARK_ENTRY_DELETED(entry);
+ tab->num_entries--;
+ update_range_for_deleted(tab, bin);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ }
+ break;
}
- return 0;
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return existing;
}
-int
-st_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)
-{
- st_table_entry *ptr = 0, **last, *tmp, *next;
+/* Traverse all entries in table TAB calling FUNC with current entry
+ key and value and zero. If the call returns ST_STOP, stop
+ traversing. If the call returns ST_DELETE, delete the current
+ entry from the table. In case of ST_CHECK or ST_CONTINUE, continue
+ traversing. The function returns zero unless an error is found.
+ CHECK_P is flag of st_foreach_check call. The behavior is a bit
+ different for ST_CHECK and when the current element is removed
+ during traversing. */
+static inline int
+st_general_foreach(st_table *tab, int (*func)(ANYARGS), st_data_t arg,
+ int check_p) {
+ st_index_t bin;
+ st_index_t bin_ind;
+ st_table_entry *entries, *curr_entry_ptr;
enum st_retval retval;
- struct list_head *head;
- st_index_t i;
-
- if (table->entries_packed) {
- for (i = 0; i < table->real_entries; i++) {
- st_data_t key, val;
- st_index_t hash;
- key = PKEY(table, i);
- val = PVAL(table, i);
- hash = PHASH(table, i);
- retval = (*func)(key, val, arg, 0);
- if (!table->entries_packed) {
- FIND_ENTRY(table, ptr, hash, i);
- if (!ptr) return 0;
- head = st_head(table);
- next = list_entry(ptr->olist.next, st_table_entry, olist);
- goto unpacked;
+ st_index_t i, rebuilds_num;
+ st_hash_t hash;
+ st_data_t key;
+ int error_p, packed_p = tab->bins == NULL;
+
+ st_assert(tab->entries_start <= tab->entries_bound);
+ entries = tab->entries;
+ /* The bound can change inside the loop even without rebuilding
+ the table, e.g. by an entry inesrtion. */
+ for (i = tab->entries_start; i < tab->entries_bound; i++) {
+ curr_entry_ptr = &entries[i];
+ if (EXPECT(DELETED_ENTRY_P(curr_entry_ptr), 0))
+ continue;
+ key = curr_entry_ptr->key;
+ rebuilds_num = tab->rebuilds_num;
+ hash = curr_entry_ptr->hash;
+ retval = (*func)(key, curr_entry_ptr->record, arg, 0);
+ if (rebuilds_num != tab->rebuilds_num) {
+ entries = tab->entries;
+ packed_p = tab->bins == NULL;
+ if (packed_p) {
+ i = find_entry(tab, hash, key);
+ error_p = i == UNDEFINED_ENTRY_IND;
+ } else {
+ i = find_table_entry_ind(tab, hash, key);
+ error_p = i == UNDEFINED_ENTRY_IND;
+ i -= ENTRY_BASE;
}
- switch (retval) {
- case ST_CONTINUE:
- break;
- case ST_CHECK:
- case ST_STOP:
- return 0;
- case ST_DELETE:
- remove_packed_entry(table, i);
- i--;
- break;
+ if (error_p && check_p) {
+ /* call func with error notice */
+ retval = (*func)(0, 0, arg, 1);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ return 1;
}
+ curr_entry_ptr = &entries[i];
}
- return 0;
- }
-
- head = st_head(table);
- list_for_each_safe(head, ptr, next, olist) {
- i = hash_pos(ptr->hash, table->num_bins);
- retval = (*func)(ptr->key, ptr->record, arg, 0);
- unpacked:
switch (retval) {
- case ST_CONTINUE:
+ case ST_CONTINUE:
break;
- case ST_CHECK:
- case ST_STOP:
+ case ST_CHECK:
+ if (check_p)
+ break;
+ case ST_STOP:
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
return 0;
- case ST_DELETE:
- last = &table->bins[hash_pos(ptr->hash, table->num_bins)];
- for (; (tmp = *last) != 0; last = &tmp->next) {
- if (ptr == tmp) {
- *last = ptr->next;
- remove_entry(table, ptr);
- st_free_entry(ptr);
+ case ST_DELETE:
+ if (packed_p) {
+ bin = find_entry(tab, hash, curr_entry_ptr->key);
+ if (bin == UNDEFINED_ENTRY_IND)
+ break;
+ } else {
+ bin_ind = find_table_bin_ind(tab, hash, curr_entry_ptr->key);
+ if (bin_ind == UNDEFINED_BIN_IND)
break;
- }
+ bin = get_bin(tab->bins, get_size_ind(tab), bin_ind) - ENTRY_BASE;
+ MARK_BIN_DELETED(tab, bin_ind);
}
- if (table->num_entries == 0) return 0;
+ st_assert(&entries[bin] == curr_entry_ptr);
+ MARK_ENTRY_DELETED(curr_entry_ptr);
+ tab->num_entries--;
+ update_range_for_deleted(tab, bin);
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
+ break;
}
}
+#ifdef ST_DEBUG
+ st_check(tab);
+#endif
return 0;
}
-static st_index_t
-get_keys(const st_table *table, st_data_t *keys, st_index_t size,
- int check, st_data_t never)
-{
- st_data_t key;
- st_data_t *keys_start = keys;
-
- if (table->entries_packed) {
- st_index_t i;
+int
+st_foreach(st_table *tab, int (*func)(ANYARGS), st_data_t arg) {
+ return st_general_foreach(tab, func, arg, FALSE);
+}
- if (size > table->real_entries) size = table->real_entries;
- for (i = 0; i < size; i++) {
- key = PKEY(table, i);
- if (check && key == never) continue;
- *keys++ = key;
- }
- }
- else {
- st_table_entry *ptr = 0;
- st_data_t *keys_end = keys + size;
+/* See comments for function st_delete_safe. */
+int
+st_foreach_check(st_table *tab, int (*func)(ANYARGS), st_data_t arg,
+ st_data_t never ATTRIBUTE_UNUSED) {
+ return st_general_foreach(tab, func, arg, TRUE);
+}
- list_for_each(st_head(table), ptr, olist) {
- if (keys >= keys_end) break;
- key = ptr->key;
- if (check && key == never) continue;
+/* Set up array KEYS by at most SIZE keys of head table TAB entries.
+ Return the number of keys set up in array KEYS. */
+static inline st_index_t
+st_general_keys(st_table *tab, st_data_t *keys, st_index_t size) {
+ st_index_t i, bound;
+ st_data_t key, *keys_start, *keys_end;
+ st_table_entry *curr_entry_ptr, *entries = tab->entries;
+
+ bound = tab->entries_bound;
+ keys_start = keys;
+ keys_end = keys + size;
+ for (i = tab->entries_start; i < bound; i++) {
+ if (keys == keys_end)
+ break;
+ curr_entry_ptr = &entries[i];
+ key = curr_entry_ptr->key;
+ if (! DELETED_ENTRY_P(curr_entry_ptr))
*keys++ = key;
- }
}
return keys - keys_start;
}
st_index_t
-st_keys(st_table *table, st_data_t *keys, st_index_t size)
-{
- return get_keys(table, keys, size, 0, 0);
+st_keys(st_table *tab, st_data_t *keys, st_index_t size) {
+ return st_general_keys(tab, keys, size);
}
+/* See comments for function st_delete_safe. */
st_index_t
-st_keys_check(st_table *table, st_data_t *keys, st_index_t size, st_data_t never)
-{
- return get_keys(table, keys, size, 1, never);
+st_keys_check(st_table *tab, st_data_t *keys, st_index_t size,
+ st_data_t never ATTRIBUTE_UNUSED) {
+ return st_general_keys(tab, keys, size);
}
-static st_index_t
-get_values(const st_table *table, st_data_t *values, st_index_t size,
- int check, st_data_t never)
-{
- st_data_t key;
- st_data_t *values_start = values;
-
- if (table->entries_packed) {
- st_index_t i;
-
- if (size > table->real_entries) size = table->real_entries;
- for (i = 0; i < size; i++) {
- key = PKEY(table, i);
- if (check && key == never) continue;
- *values++ = PVAL(table, i);
- }
- }
- else {
- st_table_entry *ptr = 0;
- st_data_t *values_end = values + size;
-
- list_for_each(st_head(table), ptr, olist) {
- if (values >= values_end) break;
- key = ptr->key;
- if (check && key == never) continue;
- *values++ = ptr->record;
- }
+/* Set up array VALUES by at most SIZE values of head table TAB
+ entries. Return the number of values set up in array VALUES. */
+static inline st_index_t
+st_general_values(st_table *tab, st_data_t *values, st_index_t size) {
+ st_index_t i, bound;
+ st_data_t *values_start, *values_end;
+ st_table_entry *curr_entry_ptr, *entries = tab->entries;
+
+ values_start = values;
+ values_end = values + size;
+ bound = tab->entries_bound;
+ st_assert(bound != 0);
+ for (i = tab->entries_start; i < bound; i++) {
+ if (values == values_end)
+ break;
+ curr_entry_ptr = &entries[i];
+ if (! DELETED_ENTRY_P(curr_entry_ptr))
+ *values++ = curr_entry_ptr->record;
}
return values - values_start;
}
st_index_t
-st_values(st_table *table, st_data_t *values, st_index_t size)
-{
- return get_values(table, values, size, 0, 0);
+st_values(st_table *tab, st_data_t *values, st_index_t size) {
+ return st_general_values(tab, values, size);
}
+/* See comments for function st_delete_safe. */
st_index_t
-st_values_check(st_table *table, st_data_t *values, st_index_t size, st_data_t never)
-{
- return get_values(table, values, size, 1, never);
+st_values_check(st_table *tab, st_data_t *values, st_index_t size,
+ st_data_t never ATTRIBUTE_UNUSED) {
+ return st_general_values(tab, values, size);
}
-
-#if 0 /* unused right now */
-int
-st_reverse_foreach_check(st_table *table, int (*func)(ANYARGS), st_data_t arg, st_data_t never)
-{
- st_table_entry *ptr, **last, *tmp, *next;
- struct list_head *head;
- enum st_retval retval;
- st_index_t i;
-
- if (table->entries_packed) {
- for (i = table->real_entries; 0 < i;) {
- st_data_t key, val;
- st_index_t hash;
- --i;
- key = PKEY(table, i);
- val = PVAL(table, i);
- hash = PHASH(table, i);
- if (key == never) continue;
- retval = (*func)(key, val, arg, 0);
- if (!table->entries_packed) {
- FIND_ENTRY(table, ptr, hash, i);
- if (retval == ST_CHECK) {
- if (!ptr) goto deleted;
- }
- if (table->num_entries == 0) return 0;
- head = st_head(table);
- next = list_entry(ptr->olist.next, st_table_entry, olist);
- goto unpacked;
- }
- switch (retval) {
- case ST_CHECK: /* check if hash is modified during iteration */
- if (PHASH(table, i) == 0 && PKEY(table, i) == never) {
- break;
- }
- i = find_packed_index_from(table, hash, key, i);
- if (i >= table->real_entries) {
- i = find_packed_index(table, hash, key);
- if (i >= table->real_entries) goto deleted;
- }
- /* fall through */
- case ST_CONTINUE:
- break;
- case ST_STOP:
- return 0;
- case ST_DELETE:
- remove_safe_packed_entry(table, i, never);
- break;
- }
- }
- return 0;
- }
-
- head = st_head(table);
- list_for_each_rev_safe(head, ptr, next, olist) {
- if (ptr->key != never) {
- i = hash_pos(ptr->hash, table->num_bins);
- retval = (*func)(ptr->key, ptr->record, arg, 0);
- unpacked:
- switch (retval) {
- case ST_CHECK: /* check if hash is modified during iteration */
- for (tmp = table->bins[i]; tmp != ptr; tmp = tmp->next) {
- if (!tmp) {
- deleted:
- /* call func with error notice */
- retval = (*func)(0, 0, arg, 1);
- return 1;
- }
- }
- /* fall through */
- case ST_CONTINUE:
- break;
- case ST_STOP:
- return 0;
- case ST_DELETE:
- last = &table->bins[hash_pos(ptr->hash, table->num_bins)];
- for (; (tmp = *last) != 0; last = &tmp->next) {
- if (ptr == tmp) {
- remove_entry(table, ptr);
- ptr->key = ptr->record = never;
- ptr->hash = 0;
- break;
- }
- }
- if (table->num_entries == 0) return 0;
- }
- }
- }
- return 0;
-}
-
-int
-st_reverse_foreach(st_table *table, int (*func)(ANYARGS), st_data_t arg)
-{
- st_table_entry *ptr, **last, *tmp, *next;
- enum st_retval retval;
- struct list_head *head;
- st_index_t i;
-
- if (table->entries_packed) {
- for (i = table->real_entries; 0 < i;) {
- st_data_t key, val;
- st_index_t hash;
- --i;
- key = PKEY(table, i);
- val = PVAL(table, i);
- hash = PHASH(table, i);
- retval = (*func)(key, val, arg, 0);
- if (!table->entries_packed) {
- FIND_ENTRY(table, ptr, hash, i);
- if (!ptr) return 0;
- head = st_head(table);
- next = list_entry(ptr->olist.next, st_table_entry, olist);
- goto unpacked;
- }
- switch (retval) {
- case ST_CONTINUE:
- break;
- case ST_CHECK:
- case ST_STOP:
- return 0;
- case ST_DELETE:
- remove_packed_entry(table, i);
- break;
- }
- }
- return 0;
- }
-
- head = st_head(table);
- list_for_each_rev_safe(head, ptr, next, olist) {
- i = hash_pos(ptr->hash, table->num_bins);
- retval = (*func)(ptr->key, ptr->record, arg, 0);
- unpacked:
- switch (retval) {
- case ST_CONTINUE:
- break;
- case ST_CHECK:
- case ST_STOP:
- return 0;
- case ST_DELETE:
- last = &table->bins[hash_pos(ptr->hash, table->num_bins)];
- for (; (tmp = *last) != 0; last = &tmp->next) {
- if (ptr == tmp) {
- *last = ptr->next;
- remove_entry(table, ptr);
- st_free_entry(ptr);
- break;
- }
- }
- if (table->num_entries == 0) return 0;
- }
- }
- return 0;
-}
-#endif
-
/*
* hash_32 - 32 bit Fowler/Noll/Vo FNV-1a hash code
*
--
EW
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 2/3] https://bugs.ruby-lang.org/attachments/download/5932/hash.patch
2016-04-30 1:04 [PATCH 0/3] patches from https://bugs.ruby-lang.org/issues/12142 Eric Wong
2016-04-30 1:04 ` [PATCH 1/3] https://bugs.ruby-lang.org/attachments/download/5931/base.patch Eric Wong
@ 2016-04-30 1:04 ` Eric Wong
2016-04-30 1:04 ` [PATCH 3/3] https://bugs.ruby-lang.org/attachments/download/5933/strong_hash.patch Eric Wong
2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2016-04-30 1:04 UTC (permalink / raw)
To: spew
From: Vladimir Makarov <vmakarov@redhat.com>
Sat Apr 30 06:28:13 2016 Vladimir Makarov <vmakarov@redhat.com>
* hash.c (rb_dbl_long_hash): New.
(any_hash): Add inline. Use common hashing for Qundef.
Use rb_dbl_long_hash for double hashing.
(rb_num_hash_start): Remove.
(prime1, prime2, mult_and_mix, key64_hash): New.
(rb_objid_hash, rb_ident_hash): Use key64_hash.
* internal.h (rb_dbl_long_hash): New.
* numeric.c (rb_dbl_hash): Call rb_dbl_long_hash.
---
hash.c | 77 ++++++++++++++++++++++++++++++++++++++++----------------------
internal.h | 1 +
numeric.c | 7 +-----
3 files changed, 52 insertions(+), 33 deletions(-)
diff --git a/hash.c b/hash.c
index 19f565a..bb95b2f 100644
--- a/hash.c
+++ b/hash.c
@@ -145,14 +145,30 @@ rb_hash(VALUE obj)
long rb_objid_hash(st_index_t index);
-static st_index_t
+long
+rb_dbl_long_hash(double d)
+{
+ /* normalize -0.0 to 0.0 */
+ if (d == 0.0) d = 0.0;
+#if SIZEOF_INT == SIZEOF_VOIDP
+ return rb_memhash(&d, sizeof(d));
+#else
+ {
+ union {double d; uint64_t i;} u;
+
+ u.d = d;
+ return rb_objid_hash(u.i);
+ }
+#endif
+}
+
+static inline st_index_t
any_hash(VALUE a, st_index_t (*other_func)(VALUE))
{
VALUE hval;
st_index_t hnum;
if (SPECIAL_CONST_P(a)) {
- if (a == Qundef) return 0;
if (STATIC_SYM_P(a)) {
hnum = a >> (RUBY_SPECIAL_SHIFT + ID_SCOPE_SHIFT);
goto out;
@@ -175,8 +191,7 @@ any_hash(VALUE a, st_index_t (*other_func)(VALUE))
}
else if (BUILTIN_TYPE(a) == T_FLOAT) {
flt:
- hval = rb_dbl_hash(rb_float_value(a));
- hnum = FIX2LONG(hval);
+ hnum = rb_dbl_long_hash(rb_float_value(a));
}
else {
hnum = other_func(a);
@@ -199,34 +214,42 @@ rb_any_hash(VALUE a)
return any_hash(a, obj_any_hash);
}
-static st_index_t
-rb_num_hash_start(st_index_t n)
+/* Here is a hash function for 64-bit key. It is about 5 times faster
+ (2 times faster when uint128 type is absent) on Haswell than
+ tailored Spooky or City hash function can be. */
+
+/* Here we two primes with random bit generation. */
+static const uint64_t prime1 = 0x2e0bb864e9ea7df5ULL;
+static const uint64_t prime2 = 0xcdb32970830fcaa1ULL;
+
+
+static inline uint64_t
+mult_and_mix (uint64_t m1, uint64_t m2)
{
- /*
- * This hash function is lightly-tuned for Ruby. Further tuning
- * should be possible. Notes:
- *
- * - (n >> 3) alone is great for heap objects and OK for fixnum,
- * however symbols perform poorly.
- * - (n >> (RUBY_SPECIAL_SHIFT+3)) was added to make symbols hash well,
- * n.b.: +3 to remove most ID scope, +1 worked well initially, too
- * n.b.: +1 (instead of 3) worked well initially, too
- * - (n << 16) was finally added to avoid losing bits for fixnums
- * - avoid expensive modulo instructions, it is currently only
- * shifts and bitmask operations.
- */
- return (n >> (RUBY_SPECIAL_SHIFT + 3) ^ (n << 16)) ^ (n >> 3);
+#if defined(__GNUC__) && UINT_MAX != ULONG_MAX
+ __uint128_t r = (__uint128_t) m1 * (__uint128_t) m2;
+ return (uint64_t) (r >> 64) ^ (uint64_t) r;
+#else
+ uint64_t hm1 = m1 >> 32, hm2 = m2 >> 32;
+ uint64_t lm1 = m1, lm2 = m2;
+ uint64_t v64_128 = hm1 * hm2;
+ uint64_t v32_96 = hm1 * lm2 + lm1 * hm2;
+ uint64_t v1_32 = lm1 * lm2;
+
+ return (v64_128 + (v32_96 >> 32)) ^ ((v32_96 << 32) + v1_32);
+#endif
+}
+
+static inline uint64_t
+key64_hash (uint64_t key, uint32_t seed)
+{
+ return mult_and_mix(key + seed, prime1);
}
long
rb_objid_hash(st_index_t index)
{
- st_index_t hnum = rb_num_hash_start(index);
-
- hnum = rb_hash_start(hnum);
- hnum = rb_hash_uint(hnum, (st_index_t)rb_any_hash);
- hnum = rb_hash_end(hnum);
- return hnum;
+ return key64_hash (index, prime2);
}
static st_index_t
@@ -269,7 +292,7 @@ rb_ident_hash(st_data_t n)
}
#endif
- return (st_index_t)rb_num_hash_start((st_index_t)n);
+ return (st_index_t) key64_hash((st_index_t)n, prime2);
}
static const struct st_hash_type identhash = {
diff --git a/internal.h b/internal.h
index 148f160..44f6d73 100644
--- a/internal.h
+++ b/internal.h
@@ -953,6 +953,7 @@ VALUE rb_hash_has_key(VALUE hash, VALUE key);
VALUE rb_hash_default_value(VALUE hash, VALUE key);
VALUE rb_hash_set_default_proc(VALUE hash, VALUE proc);
long rb_objid_hash(st_index_t index);
+long rb_dbl_long_hash(double d);
st_table *rb_init_identtable(void);
st_table *rb_init_identtable_with_size(st_index_t size);
diff --git a/numeric.c b/numeric.c
index 8335a2c..4a66a7b 100644
--- a/numeric.c
+++ b/numeric.c
@@ -1250,12 +1250,7 @@ flo_hash(VALUE num)
VALUE
rb_dbl_hash(double d)
{
- st_index_t hash;
-
- /* normalize -0.0 to 0.0 */
- if (d == 0.0) d = 0.0;
- hash = rb_memhash(&d, sizeof(d));
- return LONG2FIX(hash);
+ return LONG2FIX(rb_dbl_long_hash (d));
}
VALUE
--
EW
^ permalink raw reply related [flat|nested] 4+ messages in thread
* [PATCH 3/3] https://bugs.ruby-lang.org/attachments/download/5933/strong_hash.patch
2016-04-30 1:04 [PATCH 0/3] patches from https://bugs.ruby-lang.org/issues/12142 Eric Wong
2016-04-30 1:04 ` [PATCH 1/3] https://bugs.ruby-lang.org/attachments/download/5931/base.patch Eric Wong
2016-04-30 1:04 ` [PATCH 2/3] https://bugs.ruby-lang.org/attachments/download/5932/hash.patch Eric Wong
@ 2016-04-30 1:04 ` Eric Wong
2 siblings, 0 replies; 4+ messages in thread
From: Eric Wong @ 2016-04-30 1:04 UTC (permalink / raw)
To: spew
From: Vladimir Makarov <vmakarov@redhat.com>
Sat Apr 30 06:32:41 2016 Vladimir Makarov <vmakarov@redhat.com>
* include/ruby/st.h (st_hash_type): New field strong_hash.
(struct st_table): New fields curr_hash and inside_rebuild_p.
* st.c (do_hash): Use curr_hash.
(make_tab_empty): Set up curr_hash.
(st_init_table_with_size): Initialize inside_rebuld_p.
(rebuild_table): Set up curr_hash and inside_rebuild_p.
(reset_entry_hashes): New.
(HIT_THRESHOULD_FOR_STRONG_HASH): New.
(find_table_bin_ptr_and_reserve): Switch to the strong hash when
it is necessary.
* hash.c (str_seed): New.
(any_hash): Rename to any_hash_general. Add parameter
strong_p. Use it to choose rb_str_hash or st_hash.
(any_hash_weak, rb_any_hash_weak, any_hash): New.
(objhash): Add rb_any_hash_weak.
---
include/ruby/st.h | 9 +++++++++
st.c | 46 +++++++++++++++++++++++++++++++++++++++++++++-
2 files changed, 54 insertions(+), 1 deletion(-)
diff --git a/include/ruby/st.h b/include/ruby/st.h
index b845755..fc86cb4 100644
--- a/include/ruby/st.h
+++ b/include/ruby/st.h
@@ -61,6 +61,11 @@ typedef char st_check_for_sizeof_st_index_t[SIZEOF_VOIDP == (int)sizeof(st_index
struct st_hash_type {
int (*compare)(ANYARGS /*st_data_t, st_data_t*/); /* st_compare_func* */
st_index_t (*hash)(ANYARGS /*st_data_t*/); /* st_hash_func* */
+ /* The following is an optional func for stronger hash. When we
+ have many different keys with the same hash we can switch to
+ use it to prevent a denial attack with usage of hash table
+ collisions. */
+ st_index_t (*strong_hash)(ANYARGS /*st_data_t*/);
};
#if defined(HAVE_BUILTIN___BUILTIN_CHOOSE_EXPR) && defined(HAVE_BUILTIN___BUILTIN_TYPES_COMPATIBLE_P)
@@ -77,8 +82,12 @@ struct st_table_entry; /* defined in st.c */
struct st_table {
/* Cached features of the table -- see st.c for more details. */
unsigned char entry_power, bin_power, size_ind;
+ /* True when we are rebuilding the table. */
+ unsigned char inside_rebuild_p;
/* How many times the table was rebuilt. */
unsigned int rebuilds_num;
+ /* Currently used hash function. */
+ st_index_t (*curr_hash)(ANYARGS /*st_data_t*/);
const struct st_hash_type *type;
/* Number of entries currently in the table. */
st_index_t num_entries;
diff --git a/st.c b/st.c
index f63dd56..d632c49 100644
--- a/st.c
+++ b/st.c
@@ -304,7 +304,7 @@ struct st_features features[] = {
/* Return hash value of KEY for table TAB. */
static inline st_hash_t
do_hash(st_data_t key, st_table *tab) {
- st_index_t h = (st_index_t)(tab->type->hash)(key);
+ st_index_t h = (st_index_t)(tab->curr_hash)(key);
#if SIZEOF_INT == SIZEOF_VOIDP
st_hash_t hash = h;
#else
@@ -455,6 +455,7 @@ initialize_bins(st_table *tab) {
static void
make_tab_empty(st_table *tab)
{
+ tab->curr_hash = tab->type->hash;
tab->num_entries = 0;
tab->entries_start = tab->entries_bound = 0;
if (tab->bins != NULL)
@@ -566,6 +567,7 @@ st_init_table_with_size(const struct st_hash_type *type, st_index_t size) {
tab->entry_power = n;
tab->bin_power = features[n].bin_power;
tab->size_ind = features[n].size_ind;
+ tab->inside_rebuild_p = FALSE;
if (n <= MAX_POWER2_FOR_TABLES_WITHOUT_BINS)
tab->bins = NULL;
else
@@ -721,6 +723,7 @@ rebuild_table(st_table *tab) {
st_assert(tab != NULL);
bound = tab->entries_bound;
entries = tab->entries;
+ tab->inside_rebuild_p = TRUE;
if ((2 * tab->num_entries <= get_allocated_entries(tab)
&& REBUILD_THRESHOLD * tab->num_entries > get_allocated_entries(tab))
|| tab->num_entries < (1 << MINIMAL_POWER2)) {
@@ -734,6 +737,8 @@ rebuild_table(st_table *tab) {
else {
new_tab = st_init_table_with_size(tab->type,
2 * tab->num_entries - 1);
+ st_assert(new_tab->curr_hash == new_tab->type->hash);
+ new_tab->curr_hash = tab->curr_hash;
new_entries = new_tab->entries;
}
ni = 0;
@@ -772,6 +777,7 @@ rebuild_table(st_table *tab) {
tab->entries_start = 0;
tab->entries_bound = tab->num_entries;
tab->rebuilds_num++;
+ tab->inside_rebuild_p = FALSE;
#ifdef ST_DEBUG
st_check(tab);
#endif
@@ -934,6 +940,28 @@ find_table_bin_ind_direct(st_table *tab, st_hash_t hash_value, st_data_t key) {
}
}
+/* Recalculate hashes of entries in table TAB. */
+static void
+reset_entry_hashes (st_table *tab)
+{
+ st_index_t i, bound;
+ st_table_entry *entries, *curr_entry_ptr;
+
+ bound = tab->entries_bound;
+ entries = tab->entries;
+ for (i = tab->entries_start; i < bound; i++) {
+ curr_entry_ptr = &entries[i];
+ if (! DELETED_ENTRY_P(curr_entry_ptr))
+ curr_entry_ptr->hash = do_hash(curr_entry_ptr->key, tab);
+ }
+}
+
+/* If we have the following number of collisions with different keys
+ but with the same hash during finding a bin for new entry
+ inclusions, possibly a denial attack is going on. Start to use a
+ stronger hash. */
+#define HIT_THRESHOULD_FOR_STRONG_HASH 10
+
/* Return index of table TAB bin for HASH_VALUE and KEY through
BIN_IND and the pointed value as the function result. Reserve the
bin for inclusion of the corresponding entry into the table if it
@@ -955,10 +983,12 @@ find_table_bin_ptr_and_reserve(st_table *tab, st_hash_t *hash_value,
st_index_t entry_index;
st_index_t first_deleted_bin_ind;
st_table_entry *entries;
+ int hit;
st_assert(tab != NULL && tab->bins != NULL
&& tab->entries_bound <= get_allocated_entries(tab)
&& tab->entries_start <= tab->entries_bound);
+ repeat:
ind = hash_bin(curr_hash_value, tab);
#ifdef QUADRATIC_PROBE
d = 1;
@@ -968,6 +998,7 @@ find_table_bin_ptr_and_reserve(st_table *tab, st_hash_t *hash_value,
FOUND_BIN;
first_deleted_bin_ind = UNDEFINED_BIN_IND;
entries = tab->entries;
+ hit = 0;
for (;;) {
entry_index = get_bin(tab->bins, get_size_ind(tab), ind);
if (EMPTY_BIN_P(entry_index)) {
@@ -982,6 +1013,19 @@ find_table_bin_ptr_and_reserve(st_table *tab, st_hash_t *hash_value,
} else if (! DELETED_BIN_P(entry_index)) {
if (PTR_EQUAL(tab, &entries[entry_index - ENTRY_BASE], curr_hash_value, key))
break;
+ if (curr_hash_value == entries[entry_index - ENTRY_BASE].hash) {
+ hit++;
+ if (hit > HIT_THRESHOULD_FOR_STRONG_HASH
+ && tab->curr_hash != tab->type->strong_hash
+ && tab->type->strong_hash != NULL
+ && ! tab->inside_rebuild_p) {
+ tab->curr_hash = tab->type->strong_hash;
+ *hash_value = curr_hash_value = do_hash(key, tab);
+ reset_entry_hashes(tab);
+ rebuild_table(tab);
+ goto repeat;
+ }
+ }
} else if (first_deleted_bin_ind == UNDEFINED_BIN_IND)
first_deleted_bin_ind = ind;
#ifdef QUADRATIC_PROBE
--
EW
^ permalink raw reply related [flat|nested] 4+ messages in thread
end of thread, other threads:[~2016-04-30 1:04 UTC | newest]
Thread overview: 4+ messages (download: mbox.gz follow: Atom feed
-- links below jump to the message on this page --
2016-04-30 1:04 [PATCH 0/3] patches from https://bugs.ruby-lang.org/issues/12142 Eric Wong
2016-04-30 1:04 ` [PATCH 1/3] https://bugs.ruby-lang.org/attachments/download/5931/base.patch Eric Wong
2016-04-30 1:04 ` [PATCH 2/3] https://bugs.ruby-lang.org/attachments/download/5932/hash.patch Eric Wong
2016-04-30 1:04 ` [PATCH 3/3] https://bugs.ruby-lang.org/attachments/download/5933/strong_hash.patch Eric Wong
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