icache: Don't output X on i_out.insn

decode1 has a lot of logic that uses i_out.insn without first looking at
i_iout.valid. Play it safe and never output X state.

Signed-off-by: Anton Blanchard <anton@linux.ibm.com>

diff --git a/icache.vhdl b/icache.vhdl
index a51209e75fe3416a3fc0450fc4fc5177d5daa2a7..e8acaa74e62985611a865ac08c94638cc017f07d 100644 (file)
--- a/icache.vhdl
+++ b/icache.vhdl
@@ -555,7 +555,11 @@ begin
        --       I prefer not to do just yet as it would force fetch2 to know about
        --       some of the cache geometry information.
        --
-        i_out.insn <= read_insn_word(r.hit_nia, cache_out(r.hit_way));
+       if r.hit_valid = '1' then
+            i_out.insn <= read_insn_word(r.hit_nia, cache_out(r.hit_way));
+       else
+            i_out.insn <= (others => '0');
+       end if;
        i_out.valid <= r.hit_valid;
        i_out.nia <= r.hit_nia;
        i_out.stop_mark <= r.hit_smark;