[Qemu-arm] [PATCH 01/10] exec-all: add tb_from_jmp_cache

[Emilio G. Cota]

This paves the way for upcoming changes.

Signed-off-by: Emilio G. Cota <address@hidden>
---
 cpu-exec.c              | 19 +++++++++++++++++++
 include/exec/exec-all.h |  2 +-
 2 files changed, 20 insertions(+), 1 deletion(-)

diff --git a/cpu-exec.c b/cpu-exec.c
index 748cb66..ce9750a 100644
--- a/cpu-exec.c
+++ b/cpu-exec.c
@@ -309,6 +309,25 @@ static bool tb_cmp(const void *p, const void *d)
     return false;
 }
 
+TranslationBlock *tb_from_jmp_cache(CPUArchState *env, target_ulong vaddr)
+{
+    CPUState *cpu = ENV_GET_CPU(env);
+    TranslationBlock *tb;
+    target_ulong cs_base, pc;
+    uint32_t flags;
+
+    if (unlikely(atomic_read(&cpu->exit_request))) {
+        return NULL;
+    }
+    cpu_get_tb_cpu_state(env, &pc, &cs_base, &flags);
+    tb = atomic_rcu_read(&cpu->tb_jmp_cache[tb_jmp_cache_hash_func(vaddr)]);
+    if (likely(tb && tb->pc == vaddr && tb->cs_base == cs_base &&
+               tb->flags == flags)) {
+        return tb;
+    }
+    return NULL;
+}
+
 static TranslationBlock *tb_htable_lookup(CPUState *cpu,
                                           target_ulong pc,
                                           target_ulong cs_base,
diff --git a/include/exec/exec-all.h b/include/exec/exec-all.h
index bcde1e6..18b80bc 100644
--- a/include/exec/exec-all.h
+++ b/include/exec/exec-all.h
@@ -56,7 +56,6 @@ TranslationBlock *tb_gen_code(CPUState *cpu,
                               target_ulong pc, target_ulong cs_base,
                               uint32_t flags,
                               int cflags);
-
 void QEMU_NORETURN cpu_loop_exit(CPUState *cpu);
 void QEMU_NORETURN cpu_loop_exit_restore(CPUState *cpu, uintptr_t pc);
 void QEMU_NORETURN cpu_loop_exit_atomic(CPUState *cpu, uintptr_t pc);
@@ -368,6 +367,7 @@ struct TranslationBlock {
 void tb_free(TranslationBlock *tb);
 void tb_flush(CPUState *cpu);
 void tb_phys_invalidate(TranslationBlock *tb, tb_page_addr_t page_addr);
+TranslationBlock *tb_from_jmp_cache(CPUArchState *env, target_ulong vaddr);
 
 #if defined(USE_DIRECT_JUMP)
 
-- 
2.7.4