xref: /openbmc/qemu/accel/tcg/tb-hash.h (revision 06831001)
1 /*
2  * internal execution defines for qemu
3  *
4  *  Copyright (c) 2003 Fabrice Bellard
5  *
6  * This library is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU Lesser General Public
8  * License as published by the Free Software Foundation; either
9  * version 2.1 of the License, or (at your option) any later version.
10  *
11  * This library is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * Lesser General Public License for more details.
15  *
16  * You should have received a copy of the GNU Lesser General Public
17  * License along with this library; if not, see <http://www.gnu.org/licenses/>.
18  */
19 
20 #ifndef EXEC_TB_HASH_H
21 #define EXEC_TB_HASH_H
22 
23 #include "exec/cpu-defs.h"
24 #include "exec/exec-all.h"
25 #include "qemu/xxhash.h"
26 #include "tb-jmp-cache.h"
27 
28 #ifdef CONFIG_SOFTMMU
29 
30 /* Only the bottom TB_JMP_PAGE_BITS of the jump cache hash bits vary for
31    addresses on the same page.  The top bits are the same.  This allows
32    TLB invalidation to quickly clear a subset of the hash table.  */
33 #define TB_JMP_PAGE_BITS (TB_JMP_CACHE_BITS / 2)
34 #define TB_JMP_PAGE_SIZE (1 << TB_JMP_PAGE_BITS)
35 #define TB_JMP_ADDR_MASK (TB_JMP_PAGE_SIZE - 1)
36 #define TB_JMP_PAGE_MASK (TB_JMP_CACHE_SIZE - TB_JMP_PAGE_SIZE)
37 
38 static inline unsigned int tb_jmp_cache_hash_page(target_ulong pc)
39 {
40     target_ulong tmp;
41     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
42     return (tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK;
43 }
44 
45 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
46 {
47     target_ulong tmp;
48     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
49     return (((tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK)
50            | (tmp & TB_JMP_ADDR_MASK));
51 }
52 
53 #else
54 
55 /* In user-mode we can get better hashing because we do not have a TLB */
56 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
57 {
58     return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
59 }
60 
61 #endif /* CONFIG_SOFTMMU */
62 
63 static inline
64 uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc,
65                       uint32_t flags, uint64_t flags2, uint32_t cf_mask)
66 {
67     return qemu_xxhash8(phys_pc, pc, flags2, flags, cf_mask);
68 }
69 
70 #endif
71