include/exec/memop: Introduce memop_atomicity_bits

Split out of mmu_lookup.

Reviewed-by: Helge Deller <deller@gmx.de>
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

accel/tcg/cputlb.c

@@ -1767,20 +1767,8 @@ static bool mmu_lookup(CPUState *cpu, vaddr addr, MemOpIdx oi,
      * Device memory type require alignment.
      */
     if (unlikely(flags & TLB_CHECK_ALIGNED)) {
-        MemOp size = l->memop & MO_SIZE;
-
-        switch (l->memop & MO_ATOM_MASK) {
-        case MO_ATOM_NONE:
-            size = MO_8;
-            break;
-        case MO_ATOM_IFALIGN_PAIR:
-        case MO_ATOM_WITHIN16_PAIR:
-            size = size ? size - 1 : 0;
-            break;
-        default:
-            break;
-        }
-        if (addr & ((1 << size) - 1)) {
+        a_bits = memop_atomicity_bits(l->memop);
+        if (addr & ((1 << a_bits) - 1)) {
             cpu_unaligned_access(cpu, addr, type, l->mmu_idx, ra);
         }
     }

include/exec/memop.h

@@ -193,4 +193,28 @@ static inline unsigned memop_alignment_bits(MemOp memop)
     return a;
 }
 
+/*
+ * memop_atomicity_bits:
+ * @memop: MemOp value
+ *
+ * Extract the atomicity size from the memop.
+ */
+static inline unsigned memop_atomicity_bits(MemOp memop)
+{
+    unsigned size = memop & MO_SIZE;
+
+    switch (memop & MO_ATOM_MASK) {
+    case MO_ATOM_NONE:
+        size = MO_8;
+        break;
+    case MO_ATOM_IFALIGN_PAIR:
+    case MO_ATOM_WITHIN16_PAIR:
+        size = size ? size - 1 : 0;
+        break;
+    default:
+        break;
+    }
+    return size;
+}
+
 #endif