commit 2db59a76c421cdd1039d10e32a9798952d3ff5ba
author Max Filippov <jcmvbkbc@gmail.com> Thu Oct 30 18:07:47 2014 +0300
committer Max Filippov <jcmvbkbc@gmail.com> Wed Dec 17 05:49:32 2014 +0300
tree 300de3cb63640349d027c6c26534dd3ff881ab0f
parent 85d36377e4ff8b98119420099d445369bfd6b7bb

target-xtensa: record available window in TB flags

Record last valid 4-register window pane number in TB flags so that a
window overflow exception throw point is known at the translation time.

Signed-off-by: Max Filippov <jcmvbkbc@gmail.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>

target-xtensa/cpu.h

diff --git a/target-xtensa/cpu.h b/target-xtensa/cpu.h
index ac463f2..a1bfbf7 100644
--- a/target-xtensa/cpu.h
+++ b/target-xtensa/cpu.h
@@ -497,6 +497,8 @@
 #define XTENSA_TBFLAG_CPENABLE_MASK 0x3fc0
 #define XTENSA_TBFLAG_CPENABLE_SHIFT 6
 #define XTENSA_TBFLAG_EXCEPTION 0x4000
+#define XTENSA_TBFLAG_WINDOW_MASK 0x18000
+#define XTENSA_TBFLAG_WINDOW_SHIFT 15
 
 static inline void cpu_get_tb_cpu_state(CPUXtensaState *env, target_ulong *pc,
         target_ulong *cs_base, int *flags)
@@ -528,6 +530,16 @@
     if (cs->singlestep_enabled && env->exception_taken) {
         *flags |= XTENSA_TBFLAG_EXCEPTION;
     }
+    if (xtensa_option_enabled(env->config, XTENSA_OPTION_WINDOWED_REGISTER) &&
+        (env->sregs[PS] & (PS_WOE | PS_EXCM)) == PS_WOE) {
+        uint32_t windowstart = xtensa_replicate_windowstart(env) >>
+            (env->sregs[WINDOW_BASE] + 1);
+        uint32_t w = ctz32(windowstart | 0x8);
+
+        *flags |= w << XTENSA_TBFLAG_WINDOW_SHIFT;
+    } else {
+        *flags |= 3 << XTENSA_TBFLAG_WINDOW_SHIFT;
+    }
 }
 
 #include "exec/cpu-all.h"