target/arm: Rename 'type' to 'excret' in do_v7m_exception_exit()

In the v7M and v8M ARM ARM, the magic exception return values are
referred to as EXC_RETURN values, and in QEMU we use V7M_EXCRET_*
constants to define bits within them. Rename the 'type' variable
which holds the exception return value in do_v7m_exception_exit()
to excret, making it clearer that it does hold an EXC_RETURN value.

Signed-off-by: Peter Maydell <[email protected]>
Reviewed-by: Philippe Mathieu-Daudé <[email protected]>
Reviewed-by: Alistair Francis <[email protected]>
Reviewed-by: Richard Henderson <[email protected]>
Message-id: [email protected]

target/arm/helper.c

@@ -6212,7 +6212,7 @@ static void v7m_push_stack(ARMCPU *cpu)
 static void do_v7m_exception_exit(ARMCPU *cpu)
 {
     CPUARMState *env = &cpu->env;
-    uint32_t type;
+    uint32_t excret;
     uint32_t xpsr;
     bool ufault = false;
     bool return_to_sp_process = false;
@@ -6233,18 +6233,19 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
      * the target value up between env->regs[15] and env->thumb in
      * gen_bx(). Reconstitute it.
      */
-    type = env->regs[15];
+    excret = env->regs[15];
     if (env->thumb) {
-        type |= 1;
+        excret |= 1;
     }
 
     qemu_log_mask(CPU_LOG_INT, "Exception return: magic PC %" PRIx32
                   " previous exception %d\n",
-                  type, env->v7m.exception);
+                  excret, env->v7m.exception);
 
-    if ((type & R_V7M_EXCRET_RES1_MASK) != R_V7M_EXCRET_RES1_MASK) {
+    if ((excret & R_V7M_EXCRET_RES1_MASK) != R_V7M_EXCRET_RES1_MASK) {
         qemu_log_mask(LOG_GUEST_ERROR, "M profile: zero high bits in exception "
-                      "exit PC value 0x%" PRIx32 " are UNPREDICTABLE\n", type);
+                      "exit PC value 0x%" PRIx32 " are UNPREDICTABLE\n",
+                      excret);
     }
 
     if (env->v7m.exception != ARMV7M_EXCP_NMI) {
@@ -6255,7 +6256,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
          * which security state's faultmask to clear. (v8M ARM ARM R_KBNF.)
          */
         if (arm_feature(env, ARM_FEATURE_M_SECURITY)) {
-            int es = type & R_V7M_EXCRET_ES_MASK;
+            int es = excret & R_V7M_EXCRET_ES_MASK;
             if (armv7m_nvic_raw_execution_priority(env->nvic) >= 0) {
                 env->v7m.faultmask[es] = 0;
             }
@@ -6283,7 +6284,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
         g_assert_not_reached();
     }
 
-    switch (type & 0xf) {
+    switch (excret & 0xf) {
     case 1: /* Return to Handler */
         return_to_handler = true;
         break;
@@ -6306,7 +6307,7 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
          */
         env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK;
         armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE);
-        v7m_exception_taken(cpu, type);
+        v7m_exception_taken(cpu, excret);
         qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on existing "
                       "stackframe: failed exception return integrity check\n");
         return;
@@ -6341,14 +6342,14 @@ static void do_v7m_exception_exit(ARMCPU *cpu)
 
     /* The restored xPSR exception field will be zero if we're
      * resuming in Thread mode. If that doesn't match what the
-     * exception return type specified then this is a UsageFault.
+     * exception return excret specified then this is a UsageFault.
      */
     if (return_to_handler != arm_v7m_is_handler_mode(env)) {
         /* Take an INVPC UsageFault by pushing the stack again. */
         armv7m_nvic_set_pending(env->nvic, ARMV7M_EXCP_USAGE);
         env->v7m.cfsr[env->v7m.secure] |= R_V7M_CFSR_INVPC_MASK;
         v7m_push_stack(cpu);
-        v7m_exception_taken(cpu, type);
+        v7m_exception_taken(cpu, excret);
         qemu_log_mask(CPU_LOG_INT, "...taking UsageFault on new stackframe: "
                       "failed exception return integrity check\n");
         return;