1 files changed, 81 insertions, 0 deletions
diff --git a/host/include/generic/host/atomic128-ldst.h.inc b/host/include/generic/host/atomic128-ldst.h.inc
new file mode 100644
index 0000000..691e6a8
--- /dev/null
+++ b/host/include/generic/host/atomic128-ldst.h.inc
@@ -0,0 +1,81 @@
+/*
+ * SPDX-License-Identifier: GPL-2.0-or-later
+ * Load/store for 128-bit atomic operations, generic version.
+ *
+ * Copyright (C) 2018, 2023 Linaro, Ltd.
+ *
+ * See docs/devel/atomics.rst for discussion about the guarantees each
+ * atomic primitive is meant to provide.
+ */
+
+#ifndef HOST_ATOMIC128_LDST_H
+#define HOST_ATOMIC128_LDST_H
+
+#if defined(CONFIG_ATOMIC128)
+# define HAVE_ATOMIC128_RO 1
+# define HAVE_ATOMIC128_RW 1
+
+static inline Int128 ATTRIBUTE_ATOMIC128_OPT
+atomic16_read_ro(const Int128 *ptr)
+{
+    const __int128_t *ptr_align = __builtin_assume_aligned(ptr, 16);
+    Int128Alias r;
+
+    r.i = qatomic_read__nocheck(ptr_align);
+    return r.s;
+}
+
+static inline Int128 ATTRIBUTE_ATOMIC128_OPT
+atomic16_read_rw(Int128 *ptr)
+{
+    return atomic16_read_ro(ptr);
+}
+
+static inline void ATTRIBUTE_ATOMIC128_OPT
+atomic16_set(Int128 *ptr, Int128 val)
+{
+    __int128_t *ptr_align = __builtin_assume_aligned(ptr, 16);
+    Int128Alias v;
+
+    v.s = val;
+    qatomic_set__nocheck(ptr_align, v.i);
+}
+
+#elif defined(CONFIG_CMPXCHG128)
+# define HAVE_ATOMIC128_RO 0
+# define HAVE_ATOMIC128_RW 1
+
+Int128 QEMU_ERROR("unsupported atomic") atomic16_read_ro(const Int128 *ptr);
+
+static inline Int128 ATTRIBUTE_ATOMIC128_OPT
+atomic16_read_rw(Int128 *ptr)
+{
+    /* Maybe replace 0 with 0, returning the old value.  */
+    Int128 z = int128_make64(0);
+    return atomic16_cmpxchg(ptr, z, z);
+}
+
+static inline void ATTRIBUTE_ATOMIC128_OPT
+atomic16_set(Int128 *ptr, Int128 val)
+{
+    Int128Aligned *ptr_align = __builtin_assume_aligned(ptr, 16);
+    __int128_t old;
+    Int128Alias new;
+
+    new.s = val;
+    do {
+        old = *ptr_align;
+    } while (!__sync_bool_compare_and_swap_16(ptr_align, old, new.i));
+}
+
+#else
+# define HAVE_ATOMIC128_RO 0
+# define HAVE_ATOMIC128_RW 0
+
+/* Fallback definitions that must be optimized away, or error.  */
+Int128 QEMU_ERROR("unsupported atomic") atomic16_read_ro(const Int128 *ptr);
+Int128 QEMU_ERROR("unsupported atomic") atomic16_read_rw(Int128 *ptr);
+void QEMU_ERROR("unsupported atomic") atomic16_set(Int128 *ptr, Int128 val);
+#endif
+
+#endif /* HOST_ATOMIC128_LDST_H */