--- /dev/null
+/*
+ * THIS MATERIAL IS PROVIDED AS IS, WITH ABSOLUTELY NO WARRANTY EXPRESSED
+ * OR IMPLIED. ANY USE IS AT YOUR OWN RISK.
+ *
+ * Permission is hereby granted to use or copy this program
+ * for any purpose, provided the above notices are retained on all copies.
+ * Permission to modify the code and to distribute modified code is granted,
+ * provided the above notices are retained, and a notice that the code was
+ * modified is included with the above copyright notice.
+ */
+
+#include "../all_aligned_atomic_load_store.h"
+
+#include "../test_and_set_t_is_ao_t.h"
+
+/* There's also "isync" and "barrier"; however, for all current CPU */
+/* versions, "syncht" should suffice. Likewise, it seems that the */
+/* auto-defined versions of *_acquire, *_release or *_full suffice for */
+/* all current ISA implementations. */
+AO_INLINE void
+AO_nop_full(void)
+{
+ __asm__ __volatile__("syncht" : : : "memory");
+}
+#define AO_HAVE_nop_full
+
+/* The Hexagon has load-locked, store-conditional primitives, and so */
+/* resulting code is very nearly identical to that of PowerPC. */
+
+AO_INLINE AO_t
+AO_fetch_and_add(volatile AO_t *addr, AO_t incr)
+{
+ AO_t oldval;
+ AO_t newval;
+ __asm__ __volatile__(
+ "1:\n"
+ " %0 = memw_locked(%3);\n" /* load and reserve */
+ " %1 = add (%0,%4);\n" /* increment */
+ " memw_locked(%3,p1) = %1;\n" /* store conditional */
+ " if (!p1) jump 1b;\n" /* retry if lost reservation */
+ : "=&r"(oldval), "=&r"(newval), "+m"(*addr)
+ : "r"(addr), "r"(incr)
+ : "memory", "p1");
+ return oldval;
+}
+#define AO_HAVE_fetch_and_add
+
+AO_INLINE AO_TS_VAL_t
+AO_test_and_set(volatile AO_TS_t *addr)
+{
+ int oldval;
+ int locked_value = 1;
+
+ __asm__ __volatile__(
+ "1:\n"
+ " %0 = memw_locked(%2);\n" /* load and reserve */
+ " {\n"
+ " p2 = cmp.eq(%0,#0);\n" /* if load is not zero, */
+ " if (!p2.new) jump:nt 2f; \n" /* we are done */
+ " }\n"
+ " memw_locked(%2,p1) = %3;\n" /* else store conditional */
+ " if (!p1) jump 1b;\n" /* retry if lost reservation */
+ "2:\n" /* oldval is zero if we set */
+ : "=&r"(oldval), "+m"(*addr)
+ : "r"(addr), "r"(locked_value)
+ : "memory", "p1", "p2");
+ return (AO_TS_VAL_t)oldval;
+}
+#define AO_HAVE_test_and_set
+
+AO_INLINE int
+AO_compare_and_swap(volatile AO_t *addr, AO_t old, AO_t new_val)
+{
+ AO_t __oldval;
+ int result = 0;
+ __asm__ __volatile__(
+ "1:\n"
+ " %0 = memw_locked(%3);\n" /* load and reserve */
+ " {\n"
+ " p2 = cmp.eq(%0,%4);\n" /* if load is not equal to */
+ " if (!p2.new) jump:nt 2f; \n" /* old, fail */
+ " }\n"
+ " memw_locked(%3,p1) = %5;\n" /* else store conditional */
+ " if (!p1) jump 1b;\n" /* retry if lost reservation */
+ " %1 = #1\n" /* success, result = 1 */
+ "2:\n"
+ : "=&r" (__oldval), "+r" (result), "+m"(*addr)
+ : "r" (addr), "r" (old), "r" (new_val)
+ : "p1", "p2", "memory"
+ );
+ return result;
+}
+#define AO_HAVE_compare_and_swap
+
+#include "../ao_t_is_int.h"