tcg: Allow goto_tb to any target PC in user mode

In user mode, there's only a static address translation, TBs are always
invalidated properly and direct jumps are reset when mapping change.
Thus the destination address is always valid for direct jumps and
there's no need to restrict it to the pages the TB resides in.

Signed-off-by: Sergey Fedorov <serge.fdrv@gmail.com>
Signed-off-by: Sergey Fedorov <sergey.fedorov@linaro.org>
Cc: Riku Voipio <riku.voipio@iki.fi>
Cc: Blue Swirl <blauwirbel@gmail.com>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 14 insertions, 9 deletions

diff --git a/target-i386/translate.c b/target-i386/translate.c
index 058d85a1ab..868c26244b 100644
--- a/target-i386/translate.c
+++ b/target-i386/translate.c
@@ -2085,20 +2085,25 @@ static inline int insn_const_size(TCGMemOp ot)
     }
 }
 
+static inline bool use_goto_tb(DisasContext *s, target_ulong pc)
+{
+#ifndef CONFIG_USER_ONLY
+    return (pc & TARGET_PAGE_MASK) == (s->tb->pc & TARGET_PAGE_MASK) ||
+           (pc & TARGET_PAGE_MASK) == (s->pc_start & TARGET_PAGE_MASK);
+#else
+    return true;
+#endif
+}
+
 static inline void gen_goto_tb(DisasContext *s, int tb_num, target_ulong eip)
 {
-    TranslationBlock *tb;
-    target_ulong pc;
-
-    pc = s->cs_base + eip;
-    tb = s->tb;
-    /* NOTE: we handle the case where the TB spans two pages here */
-    if ((pc & TARGET_PAGE_MASK) == (tb->pc & TARGET_PAGE_MASK) ||
-        (pc & TARGET_PAGE_MASK) == (s->pc_start & TARGET_PAGE_MASK))  {
+    target_ulong pc = s->cs_base + eip;
+
+    if (use_goto_tb(s, pc))  {
         /* jump to same page: we can use a direct jump */
         tcg_gen_goto_tb(tb_num);
         gen_jmp_im(eip);
-        tcg_gen_exit_tb((uintptr_t)tb + tb_num);
+        tcg_gen_exit_tb((uintptr_t)s->tb + tb_num);
     } else {
         /* jump to another page: currently not optimized */
         gen_jmp_im(eip);