[PATCH] target/ppc: Fix 64-bit decrementer

[Cédric Le Goater]

The current way the mask is built can overflow with a 64-bit decrementer.
Use MAKE_64BIT_MASK instead.

Fixes: a8dafa525181 ("target/ppc: Implement large decrementer support for TCG")
Signed-off-by: Cédric Le Goater <clg@kaod.org>
---

 This was found with the QEMU Microwatt machine which uses a 64bit
 decrementer. Here is an experimental tree:

   https://github.com/legoater/qemu/tree/microwatt

 hw/ppc/ppc.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/hw/ppc/ppc.c b/hw/ppc/ppc.c
index 7375bf4fa910..a86125c50ff9 100644
--- a/hw/ppc/ppc.c
+++ b/hw/ppc/ppc.c
@@ -876,7 +876,7 @@ static void __cpu_ppc_store_decr(PowerPCCPU *cpu, uint64_t 
*nextp,
     bool negative;
 
     /* Truncate value to decr_width and sign extend for simplicity */
-    value &= ((1ULL << nr_bits) - 1);
+    value &= MAKE_64BIT_MASK(0, nr_bits);
     negative = !!(value & (1ULL << (nr_bits - 1)));
     if (negative) {
         value |= (0xFFFFFFFFULL << nr_bits);
-- 
2.31.1