[PATCH 5/6] exec: Restrict 32-bit CPUs to 32-bit address space

[Philippe Mathieu-Daudé]

It is pointless to have 32-bit CPUs see a 64-bit address
space, when they can only address the 32 lower bits.

Only create CPU address space with a size it can address.
This makes HMP 'info mtree' command easier to understand
(on 32-bit CPUs).

Signed-off-by: Philippe Mathieu-Daudé <f4bug@amsat.org>
---
This is particularly helpful with the AVR cores.
---
 exec.c | 10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

diff --git a/exec.c b/exec.c
index 5162f0d12f..d6809a9447 100644
--- a/exec.c
+++ b/exec.c
@@ -2962,9 +2962,17 @@ static void tcg_commit(MemoryListener *listener)
 
 static void memory_map_init(void)
 {
+    uint64_t system_memory_size;
+
+#if TARGET_LONG_BITS >= 64
+    system_memory_size = UINT64_MAX;
+#else
+    system_memory_size = 1ULL << TARGET_LONG_BITS;
+#endif
+
     system_memory = g_malloc(sizeof(*system_memory));
 
-    memory_region_init(system_memory, NULL, "system", UINT64_MAX);
+    memory_region_init(system_memory, NULL, "system", system_memory_size);
     address_space_init(&address_space_memory, system_memory, "memory");
 
     system_io = g_malloc(sizeof(*system_io));
-- 
2.21.3