Merge remote-tracking branch 'remotes/rth/tags/tcg-next-pull-request' into staging

tcg-next queue

# gpg: Signature made Sat 02 Jun 2018 00:12:42 BST
# gpg:                using RSA key 64DF38E8AF7E215F
# gpg: Good signature from "Richard Henderson <richard.henderson@linaro.org>"
# Primary key fingerprint: 7A48 1E78 868B 4DB6 A85A  05C0 64DF 38E8 AF7E 215F

* remotes/rth/tags/tcg-next-pull-request:
  tcg: Pass tb and index to tcg_gen_exit_tb separately

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

3 files changed, 39 insertions, 9 deletions

diff --git a/tcg/tcg-op.c b/tcg/tcg-op.c
index 6a914654f5..daa416a143 100644
--- a/tcg/tcg-op.c
+++ b/tcg/tcg-op.c
@@ -2574,10 +2574,30 @@ void tcg_gen_extr32_i64(TCGv_i64 lo, TCGv_i64 hi, TCGv_i64 arg)
 
 /* QEMU specific operations.  */
 
+void tcg_gen_exit_tb(TranslationBlock *tb, unsigned idx)
+{
+    uintptr_t val = (uintptr_t)tb + idx;
+
+    if (tb == NULL) {
+        tcg_debug_assert(idx == 0);
+    } else if (idx <= TB_EXIT_IDXMAX) {
+#ifdef CONFIG_DEBUG_TCG
+        /* This is an exit following a goto_tb.  Verify that we have
+           seen this numbered exit before, via tcg_gen_goto_tb.  */
+        tcg_debug_assert(tcg_ctx->goto_tb_issue_mask & (1 << idx));
+#endif
+    } else {
+        /* This is an exit via the exitreq label.  */
+        tcg_debug_assert(idx == TB_EXIT_REQUESTED);
+    }
+
+    tcg_gen_op1i(INDEX_op_exit_tb, val);
+}
+
 void tcg_gen_goto_tb(unsigned idx)
 {
     /* We only support two chained exits.  */
-    tcg_debug_assert(idx <= 1);
+    tcg_debug_assert(idx <= TB_EXIT_IDXMAX);
 #ifdef CONFIG_DEBUG_TCG
     /* Verify that we havn't seen this numbered exit before.  */
     tcg_debug_assert((tcg_ctx->goto_tb_issue_mask & (1 << idx)) == 0);
@@ -2594,7 +2614,7 @@ void tcg_gen_lookup_and_goto_ptr(void)
         tcg_gen_op1i(INDEX_op_goto_ptr, tcgv_ptr_arg(ptr));
         tcg_temp_free_ptr(ptr);
     } else {
-        tcg_gen_exit_tb(0);
+        tcg_gen_exit_tb(NULL, 0);
     }
 }
 
diff --git a/tcg/tcg-op.h b/tcg/tcg-op.h
index 04eb3e9e17..7513c1eb7c 100644
--- a/tcg/tcg-op.h
+++ b/tcg/tcg-op.h
@@ -782,10 +782,19 @@ static inline void tcg_gen_insn_start(target_ulong pc, target_ulong a1,
 # error "Unhandled number of operands to insn_start"
 #endif
 
-static inline void tcg_gen_exit_tb(uintptr_t val)
-{
-    tcg_gen_op1i(INDEX_op_exit_tb, val);
-}
+/**
+ * tcg_gen_exit_tb() - output exit_tb TCG operation
+ * @tb: The TranslationBlock from which we are exiting
+ * @idx: Direct jump slot index, or exit request
+ *
+ * See tcg/README for more info about this TCG operation.
+ * See also tcg.h and the block comment above TB_EXIT_MASK.
+ *
+ * For a normal exit from the TB, back to the main loop, @tb should
+ * be NULL and @idx should be 0.  Otherwise, @tb should be valid and
+ * @idx should be one of the TB_EXIT_ values.
+ */
+void tcg_gen_exit_tb(TranslationBlock *tb, unsigned idx);
 
 /**
  * tcg_gen_goto_tb() - output goto_tb TCG operation
diff --git a/tcg/tcg.h b/tcg/tcg.h
index 08f8bbfe54..509f4d65d2 100644
--- a/tcg/tcg.h
+++ b/tcg/tcg.h
@@ -1239,9 +1239,10 @@ static inline unsigned get_mmuidx(TCGMemOpIdx oi)
  * to this default (which just calls the prologue.code emitted by
  * tcg_target_qemu_prologue()).
  */
-#define TB_EXIT_MASK 3
-#define TB_EXIT_IDX0 0
-#define TB_EXIT_IDX1 1
+#define TB_EXIT_MASK      3
+#define TB_EXIT_IDX0      0
+#define TB_EXIT_IDX1      1
+#define TB_EXIT_IDXMAX    1
 #define TB_EXIT_REQUESTED 3
 
 #ifdef HAVE_TCG_QEMU_TB_EXEC