tcg: Introduce goto_ptr opcode and tcg_gen_lookup_and_goto_ptr

Instead of exporting goto_ptr directly to TCG frontends, export
tcg_gen_lookup_and_goto_ptr(), which calls goto_ptr with the pointer
returned by the lookup_tb_ptr() helper. This is the only use case
we have for goto_ptr and lookup_tb_ptr, so having this function is
very convenient. Furthermore, it trivially allows us to avoid calling
the lookup helper if goto_ptr is not implemented by the backend.

Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Emilio G. Cota <cota@braap.org>
Message-Id: <1493263764-18657-2-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-3-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-4-git-send-email-cota@braap.org>
Message-Id: <1493263764-18657-5-git-send-email-cota@braap.org>
[rth: Squashed 4 related commits.]
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/tcg/tcg.c b/tcg/tcg.c
index cb898f1..564292f 100644
--- a/tcg/tcg.c
+++ b/tcg/tcg.c
@@ -424,6 +424,11 @@ void tcg_prologue_init(TCGContext *s)
         qemu_log_unlock();
     }
 #endif
+
+    /* Assert that goto_ptr is implemented completely.  */
+    if (TCG_TARGET_HAS_goto_ptr) {
+        tcg_debug_assert(s->code_gen_epilogue != NULL);
+    }
 }
 
 void tcg_func_start(TCGContext *s)