include/exec/tb-lookup.h

   1 /*
   2  * Copyright (C) 2017, Emilio G. Cota <cota@braap.org>
   3  *
   4  * License: GNU GPL, version 2 or later.
   5  *   See the COPYING file in the top-level directory.
   6  */
   7 #ifndef EXEC_TB_LOOKUP_H
   8 #define EXEC_TB_LOOKUP_H
   9
  10 #ifdef NEED_CPU_H
  11 #include "cpu.h"
  12 #else
  13 #include "exec/poison.h"
  14 #endif
  15
  16 #include "exec/exec-all.h"
  17 #include "exec/tb-hash.h"
  18
  19 /* Might cause an exception, so have a longjmp destination ready */
  20 static inline TranslationBlock *tb_lookup(CPUState *cpu, target_ulong pc,
  21                                           target_ulong cs_base,
  22                                           uint32_t flags, uint32_t cflags)
  23 {
  24     TranslationBlock *tb;
  25     uint32_t hash;
  26
  27     /* we should never be trying to look up an INVALID tb */
  28     tcg_debug_assert(!(cflags & CF_INVALID));
  29
  30     hash = tb_jmp_cache_hash_func(pc);
  31     tb = qatomic_rcu_read(&cpu->tb_jmp_cache[hash]);
  32
  33     if (likely(tb &&
  34                tb->pc == pc &&
  35                tb->cs_base == cs_base &&
  36                tb->flags == flags &&
  37                tb->trace_vcpu_dstate == *cpu->trace_dstate &&
  38                tb_cflags(tb) == cflags)) {
  39         return tb;
  40     }
  41     tb = tb_htable_lookup(cpu, pc, cs_base, flags, cflags);
  42     if (tb == NULL) {
  43         return NULL;
  44     }
  45     qatomic_set(&cpu->tb_jmp_cache[hash], tb);
  46     return tb;
  47 }
  48
  49 #endif /* EXEC_TB_LOOKUP_H */