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-rw-r--r--erts/emulator/beam/utils.c104
1 files changed, 60 insertions, 44 deletions
diff --git a/erts/emulator/beam/utils.c b/erts/emulator/beam/utils.c
index 092a5320ba..457cada745 100644
--- a/erts/emulator/beam/utils.c
+++ b/erts/emulator/beam/utils.c
@@ -1,7 +1,7 @@
/*
* %CopyrightBegin%
*
- * Copyright Ericsson AB 1996-2016. All Rights Reserved.
+ * Copyright Ericsson AB 1996-2017. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@ -1578,16 +1578,13 @@ do { /* Lightweight mixing of constant (type info) */ \
} while (0)
Uint32
-make_internal_hash(Eterm term)
+make_internal_hash(Eterm term, Uint32 salt)
{
Uint32 hash;
- Uint32 hash_xor_pairs;
-
- ERTS_UNDEF(hash_xor_pairs, 0);
/* Optimization. Simple cases before declaration of estack. */
if (primary_tag(term) == TAG_PRIMARY_IMMED1) {
- hash = 0;
+ hash = salt;
#if ERTS_SIZEOF_ETERM == 8
UINT32_HASH_2((Uint32)term, (Uint32)(term >> 32), HCONST);
#elif ERTS_SIZEOF_ETERM == 4
@@ -1601,7 +1598,7 @@ make_internal_hash(Eterm term)
Eterm tmp;
DECLARE_ESTACK(s);
- hash = 0;
+ hash = salt;
for (;;) {
switch (primary_tag(term)) {
case TAG_PRIMARY_LIST:
@@ -1664,6 +1661,11 @@ make_internal_hash(Eterm term)
Eterm* ptr = boxed_val(term) + 1;
Uint size;
int i;
+
+ /*
+ * We rely on key-value iteration order being constant
+ * for identical maps (in this VM instance).
+ */
switch (hdr & _HEADER_MAP_SUBTAG_MASK) {
case HAMT_SUBTAG_HEAD_FLATMAP:
{
@@ -1675,26 +1677,10 @@ make_internal_hash(Eterm term)
if (size == 0)
goto pop_next;
- /* We want a hash function that is *independent* of
- * the order in which keys and values are encountered.
- * We therefore calculate context independent hashes for all .
- * key-value pairs and then xor them together.
- *
- * We *do* need to use an initial seed for each pair, i.e. the
- * hash value, so the hash value is reset for each pair with 'hash'.
- * If we don't, no additional entropy is given to the system and the
- * hash collision resolution in maps:from_list/1 would fail.
- */
- ESTACK_PUSH(s, hash_xor_pairs);
- ESTACK_PUSH(s, hash);
- ESTACK_PUSH(s, HASH_MAP_TAIL);
for (i = size - 1; i >= 0; i--) {
- ESTACK_PUSH(s, hash); /* initial seed for all pairs */
- ESTACK_PUSH(s, HASH_MAP_PAIR);
ESTACK_PUSH(s, vs[i]);
ESTACK_PUSH(s, ks[i]);
}
- hash_xor_pairs = 0;
goto pop_next;
}
case HAMT_SUBTAG_HEAD_ARRAY:
@@ -1703,10 +1689,6 @@ make_internal_hash(Eterm term)
UINT32_HASH(size, HCONST_16);
if (size == 0)
goto pop_next;
- ESTACK_PUSH(s, hash_xor_pairs);
- ESTACK_PUSH(s, hash);
- ESTACK_PUSH(s, HASH_MAP_TAIL);
- hash_xor_pairs = 0;
}
switch (hdr & _HEADER_MAP_SUBTAG_MASK) {
case HAMT_SUBTAG_HEAD_ARRAY:
@@ -1722,8 +1704,6 @@ make_internal_hash(Eterm term)
while (i) {
if (is_list(*ptr)) {
Eterm* cons = list_val(*ptr);
- ESTACK_PUSH(s, hash); /* initial seed for all pairs */
- ESTACK_PUSH(s, HASH_MAP_PAIR);
ESTACK_PUSH(s, CDR(cons));
ESTACK_PUSH(s, CAR(cons));
}
@@ -1739,7 +1719,7 @@ make_internal_hash(Eterm term)
case EXPORT_SUBTAG:
{
Export* ep = *((Export **) (export_val(term) + 1));
- /* Assumes Export entries never moves */
+ /* Assumes Export entries never move */
POINTER_HASH(ep, HCONST_14);
goto pop_next;
}
@@ -1894,7 +1874,7 @@ make_internal_hash(Eterm term)
goto pop_next;
}
default:
- erts_exit(ERTS_ERROR_EXIT, "Invalid tag in make_hash2(0x%X)\n", term);
+ erts_exit(ERTS_ERROR_EXIT, "Invalid tag in make_internal_hash(0x%X, %lu)\n", term, salt);
}
}
break;
@@ -1907,7 +1887,7 @@ make_internal_hash(Eterm term)
goto pop_next;
default:
- erts_exit(ERTS_ERROR_EXIT, "Invalid tag in make_hash2(0x%X)\n", term);
+ erts_exit(ERTS_ERROR_EXIT, "Invalid tag in make_internal_hash(0x%X, %lu)\n", term, salt);
pop_next:
if (ESTACK_ISEMPTY(s)) {
@@ -1919,17 +1899,6 @@ make_internal_hash(Eterm term)
term = ESTACK_POP(s);
switch (term) {
- case HASH_MAP_TAIL: {
- hash = (Uint32) ESTACK_POP(s);
- UINT32_HASH(hash_xor_pairs, HCONST_19);
- hash_xor_pairs = (Uint32) ESTACK_POP(s);
- goto pop_next;
- }
- case HASH_MAP_PAIR:
- hash_xor_pairs ^= hash;
- hash = (Uint32) ESTACK_POP(s); /* initial seed for all pairs */
- goto pop_next;
-
case HASH_CDR:
CONST_HASH(HCONST_18); /* Hash CDR i cons cell */
goto pop_next;
@@ -3594,7 +3563,7 @@ store_external_or_ref_(Uint **hpp, ErlOffHeap* oh, Eterm ns)
ErtsMRefThing *mreft = (ErtsMRefThing *) from_hp;
ErtsMagicBinary *mb = mreft->mb;
ASSERT(is_magic_ref_thing(from_hp));
- erts_refc_inc(&mb->refc, 2);
+ erts_refc_inc(&mb->intern.refc, 2);
OH_OVERHEAD(oh, mb->orig_size / sizeof(Eterm));
}
@@ -4835,6 +4804,53 @@ Uint64 erts_timestamp_millis(void)
#endif
}
+void *
+erts_calc_stacklimit(char *prev_c, UWord stacksize)
+{
+ /*
+ * We *don't* want this function inlined, i.e., it is
+ * risky to call this function from another function
+ * in utils.c
+ */
+
+ UWord pagesize = erts_sys_get_page_size();
+ char c;
+ char *start;
+ if (&c > prev_c) {
+ start = (char *) ((((UWord) prev_c) / pagesize) * pagesize);
+ return (void *) (start + stacksize);
+ }
+ else {
+ start = (char *) (((((UWord) prev_c) - 1) / pagesize + 1) * pagesize);
+ return (void *) (start - stacksize);
+ }
+}
+
+/*
+ * erts_check_below_limit() and
+ * erts_check_above_limit() are put
+ * in utils.c in order to prevent
+ * inlining.
+ */
+
+int
+erts_check_below_limit(char *ptr, char *limit)
+{
+ return ptr < limit;
+}
+
+int
+erts_check_above_limit(char *ptr, char *limit)
+{
+ return ptr > limit;
+}
+
+void *
+erts_ptr_id(void *ptr)
+{
+ return ptr;
+}
+
#ifdef DEBUG
/*
* Handy functions when using a debugger - don't use in the code!
generated by cgit v1.2.3 (git 2.25.1) at 2024-08-17 09:12:53 +0000