tcg: Add atomic128 helpers

Force the use of cmpxchg16b on x86_64.

Wikipedia suggests that only very old AMD64 (circa 2004) did not have
this instruction.  Further, it's required by Windows 8 so no new cpus
will ever omit it.

If we truely care about these, then we could check this at startup time
and then avoid executing paths that use it.

Reviewed-by: Emilio G. Cota <cota@braap.org>
Reviewed-by: Alex Bennée <alex.bennee@linaro.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>

1 files changed, 5 insertions, 0 deletions

diff --git a/cputlb.c b/cputlb.c
index 4f2c5002f6..845b2a7acf 100644
--- a/cputlb.c
+++ b/cputlb.c
@@ -690,6 +690,11 @@ static void *atomic_mmu_lookup(CPUArchState *env, target_ulong addr,
 #define DATA_SIZE 8
 #include "atomic_template.h"
 
+#ifdef CONFIG_ATOMIC128
+#define DATA_SIZE 16
+#include "atomic_template.h"
+#endif
+
 /* Second set of helpers are directly callable from TCG as helpers.  */
 
 #undef EXTRA_ARGS