[PATCH 12/18] target/arm: Create raise_exception_debug

[Richard Henderson]

Handle EL testing for debug exceptions in a single place.
Split out raise_exception_int as a common helper.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/internals.h    |  8 ++++++++
 target/arm/debug_helper.c | 27 ++++--------------------
 target/arm/op_helper.c    | 43 ++++++++++++++++++++++++++++++++-------
 3 files changed, 48 insertions(+), 30 deletions(-)

diff --git a/target/arm/internals.h b/target/arm/internals.h
index 685214503b..6df38db836 100644
--- a/target/arm/internals.h
+++ b/target/arm/internals.h
@@ -125,6 +125,14 @@ G_NORETURN void raise_exception_ra(CPUARMState *env, 
uint32_t excp,
                                    uint32_t syndrome,
                                    uint32_t cur_or_target_el, uintptr_t ra);
 
+/**
+ * raise_exception_debug:
+ * Similarly.  If @excp != EXCPBKPT, modify syndrome to indicate
+ * when origin and target EL are the same.
+ */
+G_NORETURN void raise_exception_debug(CPUARMState *env, uint32_t excp,
+                                      uint32_t syndrome);
+
 /*
  * For AArch64, map a given EL to an index in the banked_spsr array.
  * Note that this mapping and the AArch32 mapping defined in bank_number()
diff --git a/target/arm/debug_helper.c b/target/arm/debug_helper.c
index 08d461fd19..181ba7b042 100644
--- a/target/arm/debug_helper.c
+++ b/target/arm/debug_helper.c
@@ -417,19 +417,16 @@ void arm_debug_excp_handler(CPUState *cs)
     if (wp_hit) {
         if (wp_hit->flags & BP_CPU) {
             bool wnr = (wp_hit->flags & BP_WATCHPOINT_HIT_WRITE) != 0;
-            bool same_el = arm_debug_target_el(env) == arm_current_el(env);
 
             cs->watchpoint_hit = NULL;
 
             env->exception.fsr = arm_debug_exception_fsr(env);
             env->exception.vaddress = wp_hit->hitaddr;
-            raise_exception(env, EXCP_DATA_ABORT,
-                    syn_watchpoint(same_el, 0, wnr),
-                    arm_debug_target_el(env));
+            raise_exception_debug(env, EXCP_DATA_ABORT,
+                                  syn_watchpoint(0, 0, wnr));
         }
     } else {
         uint64_t pc = is_a64(env) ? env->pc : env->regs[15];
-        bool same_el = (arm_debug_target_el(env) == arm_current_el(env));
 
         /*
          * (1) GDB breakpoints should be handled first.
@@ -449,9 +446,7 @@ void arm_debug_excp_handler(CPUState *cs)
          * exception/security level.
          */
         env->exception.vaddress = 0;
-        raise_exception(env, EXCP_PREFETCH_ABORT,
-                        syn_breakpoint(same_el),
-                        arm_debug_target_el(env));
+        raise_exception_debug(env, EXCP_PREFETCH_ABORT, syn_breakpoint(0));
     }
 }
 
@@ -461,9 +456,6 @@ void arm_debug_excp_handler(CPUState *cs)
  */
 void HELPER(exception_bkpt_insn)(CPUARMState *env, uint32_t syndrome)
 {
-    int debug_el = arm_debug_target_el(env);
-    int cur_el = arm_current_el(env);
-
     /* FSR will only be used if the debug target EL is AArch32. */
     env->exception.fsr = arm_debug_exception_fsr(env);
     /*
@@ -472,18 +464,7 @@ void HELPER(exception_bkpt_insn)(CPUARMState *env, 
uint32_t syndrome)
      * exception/security level.
      */
     env->exception.vaddress = 0;
-    /*
-     * Other kinds of architectural debug exception are ignored if
-     * they target an exception level below the current one (in QEMU
-     * this is checked by arm_generate_debug_exceptions()). Breakpoint
-     * instructions are special because they always generate an exception
-     * to somewhere: if they can't go to the configured debug exception
-     * level they are taken to the current exception level.
-     */
-    if (debug_el < cur_el) {
-        debug_el = cur_el;
-    }
-    raise_exception(env, EXCP_BKPT, syndrome, debug_el);
+    raise_exception_debug(env, EXCP_BKPT, syndrome);
 }
 
 #if !defined(CONFIG_USER_ONLY)
diff --git a/target/arm/op_helper.c b/target/arm/op_helper.c
index 0a50dbf274..c4988b6c41 100644
--- a/target/arm/op_helper.c
+++ b/target/arm/op_helper.c
@@ -65,15 +65,11 @@ int exception_target_el(CPUARMState *env, int cur_el, 
uint32_t *psyn)
     return 1;
 }
 
-void raise_exception(CPUARMState *env, uint32_t excp, uint32_t syndrome,
-                     uint32_t cur_or_target_el)
+G_NORETURN static
+void raise_exception_int(CPUARMState *env, uint32_t excp,
+                         uint32_t syndrome, uint32_t target_el)
 {
     CPUState *cs = env_cpu(env);
-    int target_el = cur_or_target_el;
-
-    if (cur_or_target_el <= 1) {
-        target_el = exception_target_el(env, cur_or_target_el, &syndrome);
-    }
 
     assert(!excp_is_internal(excp));
     cs->exception_index = excp;
@@ -82,6 +78,39 @@ void raise_exception(CPUARMState *env, uint32_t excp, 
uint32_t syndrome,
     cpu_loop_exit(cs);
 }
 
+void raise_exception(CPUARMState *env, uint32_t excp, uint32_t syndrome,
+                     uint32_t cur_or_target_el)
+{
+    int target_el = cur_or_target_el;
+    if (cur_or_target_el <= 1) {
+        target_el = exception_target_el(env, cur_or_target_el, &syndrome);
+    }
+    raise_exception_int(env, excp, syndrome, target_el);
+}
+
+void raise_exception_debug(CPUARMState *env, uint32_t excp, uint32_t syndrome)
+{
+    int cur_el = arm_current_el(env);
+    int debug_el = arm_debug_target_el(env);
+
+    /*
+     * Most kinds of architectural debug exception are ignored if
+     * they target an exception level below the current (in QEMU
+     * this is checked by arm_generate_debug_exceptions()).
+     * Breakpoint instructions are special because they always generate
+     * an exception to somewhere: if they can't go to the configured
+     * debug exception level they are taken to the current exception level.
+     */
+    if (excp == EXCP_BKPT) {
+        debug_el = MAX(cur_el, debug_el);
+    } else {
+        assert(debug_el >= cur_el);
+        syndrome |= (debug_el == cur_el) << ARM_EL_EC_SHIFT;
+    }
+
+    raise_exception_int(env, excp, syndrome, debug_el);
+}
+
 void raise_exception_ra(CPUARMState *env, uint32_t excp, uint32_t syndrome,
                         uint32_t cur_or_target_el, uintptr_t ra)
 {
-- 
2.34.1