accel/tcg/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 2.1 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     pc = pc ^ (pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS));
  47     return (((pc >> (TARGET_PAGE_BITS - TB_JMP_PAGE_BITS)) & TB_JMP_PAGE_MASK)
  48            | (pc & TB_JMP_ADDR_MASK));
  49 }
  50
  51 #else
  52
  53 /* In user-mode we can get better hashing because we do not have a TLB */
  54 static inline unsigned int tb_jmp_cache_hash_func(target_ulong pc)
  55 {
  56     return (pc ^ (pc >> TB_JMP_CACHE_BITS)) & (TB_JMP_CACHE_SIZE - 1);
  57 }
  58
  59 #endif /* CONFIG_SOFTMMU */
  60
  61 static inline
  62 uint32_t tb_hash_func(tb_page_addr_t phys_pc, target_ulong pc, uint32_t flags,
  63                       uint32_t cf_mask, uint32_t trace_vcpu_dstate)
  64 {
  65     return qemu_xxhash7(phys_pc, pc, flags, cf_mask, trace_vcpu_dstate);
  66 }
  67
  68 #endif