include/exec/tb-hash.h

   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 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 "qemu/xxhash.h"
  24
  25 #ifdef CONFIG_SOFTMMU
  26
  27 /* Only the bottom TB_JMP_PAGE_BITS of the jump cache hash bits vary for
  28    addresses on the same page.  The top bits are the same.  This allows
  29    TLB invalidation to quickly clear a subset of the hash table.  */
  30 #define TB_JMP_PAGE_BITS (TB_JMP_CACHE_BITS / 2)
  31 #define TB_JMP_PAGE_SIZE (1 << TB_JMP_PAGE_BITS)
  32 #define TB_JMP_ADDR_MASK (TB_JMP_PAGE_SIZE - 1)
  33 #define TB_JMP_PAGE_MASK (TB_JMP_CACHE_SIZE - TB_JMP_PAGE_SIZE)
  34
  35 static inline unsigned int tb_jmp_cache_hash_page(target_ulong pc)
  36 {
  37     target_ulong tmp;
  38     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
  39     return (tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK;
  40 }
  41
  42 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
  43 {
  44     target_ulong tmp;
  45     tmp = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
  46     return (((tmp >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK)
  47            | (tmp & TB_JMP_ADDR_MASK));
  48 }
  49
  50 #else
  51
  52 /* In user-mode we can get better hashing because we do not have a TLB */
  53 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
  54 {
  55     return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
  56 }
  57
  58 #endif /* CONFIG_SOFTMMU */
  59
  60 static inline
  61 uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc, uint32_t flags,
  62                       uint32_t cf_mask, uint32_t trace_vcpu_dstate)
  63 {
  64     return qemu_xxhash7(phys_pc, pc, flags, cf_mask, trace_vcpu_dstate);
  65 }
  66
  67 #endif