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//===-- sanitizer_chained_origin_depot.cpp --------------------------------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// A storage for chained origins.
//===----------------------------------------------------------------------===//
#include "sanitizer_chained_origin_depot.h"
namespace __sanitizer {
bool ChainedOriginDepot::ChainedOriginDepotNode::eq(
hash_type hash, const args_type &args) const {
return here_id == args.here_id && prev_id == args.prev_id;
}
uptr ChainedOriginDepot::ChainedOriginDepotNode::storage_size(
const args_type &args) {
return sizeof(ChainedOriginDepotNode);
}
/* This is murmur2 hash for the 64->32 bit case.
It does not behave all that well because the keys have a very biased
distribution (I've seen 7-element buckets with the table only 14% full).
here_id is built of
* (1 bits) Reserved, zero.
* (8 bits) Part id = bits 13..20 of the hash value of here_id's key.
* (23 bits) Sequential number (each part has each own sequence).
prev_id has either the same distribution as here_id (but with 3:8:21)
split, or one of two reserved values (-1) or (-2). Either case can
dominate depending on the workload.
*/
ChainedOriginDepot::ChainedOriginDepotNode::hash_type
ChainedOriginDepot::ChainedOriginDepotNode::hash(const args_type &args) {
const u32 m = 0x5bd1e995;
const u32 seed = 0x9747b28c;
const u32 r = 24;
u32 h = seed;
u32 k = args.here_id;
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
k = args.prev_id;
k *= m;
k ^= k >> r;
k *= m;
h *= m;
h ^= k;
h ^= h >> 13;
h *= m;
h ^= h >> 15;
return h;
}
bool ChainedOriginDepot::ChainedOriginDepotNode::is_valid(
const args_type &args) {
return true;
}
void ChainedOriginDepot::ChainedOriginDepotNode::store(const args_type &args,
hash_type other_hash) {
here_id = args.here_id;
prev_id = args.prev_id;
}
ChainedOriginDepot::ChainedOriginDepotNode::args_type
ChainedOriginDepot::ChainedOriginDepotNode::load() const {
args_type ret = {here_id, prev_id};
return ret;
}
ChainedOriginDepot::ChainedOriginDepotNode::Handle
ChainedOriginDepot::ChainedOriginDepotNode::get_handle() {
return Handle(this);
}
ChainedOriginDepot::ChainedOriginDepot() {}
StackDepotStats ChainedOriginDepot::GetStats() const {
return depot.GetStats();
}
bool ChainedOriginDepot::Put(u32 here_id, u32 prev_id, u32 *new_id) {
ChainedOriginDepotDesc desc = {here_id, prev_id};
bool inserted;
ChainedOriginDepotNode::Handle h = depot.Put(desc, &inserted);
*new_id = h.valid() ? h.id() : 0;
return inserted;
}
u32 ChainedOriginDepot::Get(u32 id, u32 *other) {
ChainedOriginDepotDesc desc = depot.Get(id);
*other = desc.prev_id;
return desc.here_id;
}
void ChainedOriginDepot::LockAll() { depot.LockAll(); }
void ChainedOriginDepot::UnlockAll() { depot.UnlockAll(); }
} // namespace __sanitizer