hw/intc/arm_gicv3: Provide ich_num_aprs()

We previously open-coded the expression for the number of virtual APR
registers and the assertion that it was not going to cause us to
overflow the cs->ich_apr[] array.  Factor this out into a new
ich_num_aprs() function, for consistency with the icc_num_aprs()
function we just added for the physical APR handling.

Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220512151457.3899052-7-peter.maydell@linaro.org
Message-id: 20220506162129.2896966-6-peter.maydell@linaro.org

hw/intc/arm_gicv3_cpuif.c

@@ -49,6 +49,14 @@ static inline int icv_min_vbpr(GICv3CPUState *cs)
     return 7 - cs->vprebits;
 }
 
+static inline int ich_num_aprs(GICv3CPUState *cs)
+{
+    /* Return the number of virtual APR registers (1, 2, or 4) */
+    int aprmax = 1 << (cs->vprebits - 5);
+    assert(aprmax <= ARRAY_SIZE(cs->ich_apr[0]));
+    return aprmax;
+}
+
 /* Simple accessor functions for LR fields */
 static uint32_t ich_lr_vintid(uint64_t lr)
 {
@@ -145,9 +153,7 @@ static int ich_highest_active_virt_prio(GICv3CPUState *cs)
      * in the ICH Active Priority Registers.
      */
     int i;
-    int aprmax = 1 << (cs->vprebits - 5);
-
-    assert(aprmax <= ARRAY_SIZE(cs->ich_apr[0]));
+    int aprmax = ich_num_aprs(cs);
 
     for (i = 0; i < aprmax; i++) {
         uint32_t apr = cs->ich_apr[GICV3_G0][i] |
@@ -1333,9 +1339,7 @@ static int icv_drop_prio(GICv3CPUState *cs)
      * 32 bits are actually relevant.
      */
     int i;
-    int aprmax = 1 << (cs->vprebits - 5);
-
-    assert(aprmax <= ARRAY_SIZE(cs->ich_apr[0]));
+    int aprmax = ich_num_aprs(cs);
 
     for (i = 0; i < aprmax; i++) {
         uint64_t *papr0 = &cs->ich_apr[GICV3_G0][i];