xref: /openbmc/qemu/accel/tcg/tb-hash.h (revision 080832e4)
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 
27 #ifdef CONFIG_SOFTMMU
28 
29 /* Only the bottom TB_JMP_PAGE_BITS of the jump cache hash bits vary for
30    addresses on the same page.  The top bits are the same.  This allows
31    TLB invalidation to quickly clear a subset of the hash table.  */
32 #define TB_JMP_PAGE_BITS (TB_JMP_CACHE_BITS / 2)
33 #define TB_JMP_PAGE_SIZE (1 << TB_JMP_PAGE_BITS)
34 #define TB_JMP_ADDR_MASK (TB_JMP_PAGE_SIZE - 1)
35 #define TB_JMP_PAGE_MASK (TB_JMP_CACHE_SIZE - TB_JMP_PAGE_SIZE)
36 
37 static inline unsigned int tb_jmp_cache_hash_page(target_ulong pc)
38 {
39     target_ulong tmp;
40     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
41     return (tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK;
42 }
43 
44 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
45 {
46     target_ulong tmp;
47     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
48     return (((tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK)
49            | (tmp & TB_JMP_ADDR_MASK));
50 }
51 
52 #else
53 
54 /* In user-mode we can get better hashing because we do not have a TLB */
55 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
56 {
57     return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
58 }
59 
60 #endif /* CONFIG_SOFTMMU */
61 
62 static inline
63 uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc, uint32_t flags,
64                       uint32_t cf_mask, uint32_t trace_vcpu_dstate)
65 {
66     return qemu_xxhash7(phys_pc, pc, flags, cf_mask, trace_vcpu_dstate);
67 }
68 
69 #endif
70