diff mbox

[v1,5/6] target/arm: use DISAS_JUMP for ISB handling

Message ID 20170710154749.13624-6-alex.bennee@linaro.org
State New
Headers show

Commit Message

Alex Bennée July 10, 2017, 3:47 p.m. UTC 
While an ISB will ensure any raised IRQs happen on the next
instruction it doesn't cause any to get raised by itself. We can
therefor use DISAS_JUMP for ISB instructions and rely on the
exit_request check at the top of each TB to deal with exiting if
needed.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
---
 target/arm/translate-a64.c |  2 +-
 target/arm/translate.c     | 13 +++++++++++--
 2 files changed, 12 insertions(+), 3 deletions(-)
diff mbox

Patch

diff --git a/target/arm/translate-a64.c b/target/arm/translate-a64.c
index bde6ca934e..fd9724b890 100644
--- a/target/arm/translate-a64.c
+++ b/target/arm/translate-a64.c
@@ -1394,7 +1394,7 @@  static void handle_sync(DisasContext *s, uint32_t insn,
          * any pending interrupts immediately.
          */
         gen_a64_set_pc_im(s->pc);
-        s->is_jmp = DISAS_UPDATE;
+        s->is_jmp = DISAS_JUMP;
         return;
     default:
         unallocated_encoding(s);
diff --git a/target/arm/translate.c b/target/arm/translate.c
index e840499c6f..f7f5f917c7 100644
--- a/target/arm/translate.c
+++ b/target/arm/translate.c
@@ -1203,6 +1203,15 @@  static inline void gen_lookup_tb(DisasContext *s)
     s->is_jmp = DISAS_UPDATE;
 }
 
+/* End the current block and force a TB lookup. We may chain to the
+ * next TB but exit_req will be immediately checked so we will exit to
+ * the main loop if we need to */
+static inline void gen_jump_tb(DisasContext *s)
+{
+    tcg_gen_movi_i32(cpu_R[15], s->pc & ~1);
+    s->is_jmp = DISAS_JUMP;
+}
+
 static inline void gen_hlt(DisasContext *s, int imm)
 {
     /* HLT. This has two purposes.
@@ -8171,7 +8180,7 @@  static void disas_arm_insn(DisasContext *s, unsigned int insn)
                  * self-modifying code correctly and also to take
                  * any pending interrupts immediately.
                  */
-                gen_lookup_tb(s);
+                gen_jump_tb(s);
                 return;
             default:
                 goto illegal_op;
@@ -10564,7 +10573,7 @@  static int disas_thumb2_insn(CPUARMState *env, DisasContext *s, uint16_t insn_hw
                              * and also to take any pending interrupts
                              * immediately.
                              */
-                            gen_lookup_tb(s);
+                            gen_jump_tb(s);
                             break;
                         default:
                             goto illegal_op;