Implement the basic atomic primitives for the hexagon CPU.

(Apply commit 9136ee6)

* src/atomic_ops/sysdeps/Makefile.am (nobase_private_HEADERS): Add
hexagon.h.
* src/atomic_ops.h: Include hexagon.h file.
* src/atomic_ops/sysdeps/gcc/hexagon.h: New file.

3 files changed, 99 insertions, 1 deletions

diff --git a/src/atomic_ops.h b/src/atomic_ops.h
index 3f9000d..ee3aa73 100644
--- a/src/atomic_ops.h
+++ b/src/atomic_ops.h
@@ -262,6 +262,9 @@
 # if defined(__avr32__)
 #   include "atomic_ops/sysdeps/gcc/avr32.h"
 # endif
+# if defined(__hexagon__)
+#   include "atomic_ops/sysdeps/gcc/hexagon.h"
+# endif
 #endif /* __GNUC__ && !AO_USE_PTHREAD_DEFS */
 
 #if (defined(__IBMC__) || defined(__IBMCPP__)) && !defined(__GNUC__) \
diff --git a/src/atomic_ops/sysdeps/Makefile.am b/src/atomic_ops/sysdeps/Makefile.am
index 5f13857..d8b24dc 100644
--- a/src/atomic_ops/sysdeps/Makefile.am
+++ b/src/atomic_ops/sysdeps/Makefile.am
@@ -27,7 +27,7 @@ nobase_sysdep_HEADERS= generic_pthread.h \
 	  armcc/arm_v6.h \
 	\
 	  gcc/alpha.h gcc/arm.h gcc/avr32.h gcc/cris.h \
-	  gcc/hppa.h gcc/ia64.h gcc/m68k.h \
+	  gcc/hexagon.h gcc/hppa.h gcc/ia64.h gcc/m68k.h \
 	  gcc/mips.h gcc/powerpc.h gcc/s390.h \
 	  gcc/sh.h gcc/sparc.h gcc/x86.h gcc/x86_64.h \
 	\
diff --git a/src/atomic_ops/sysdeps/gcc/hexagon.h b/src/atomic_ops/sysdeps/gcc/hexagon.h
new file mode 100644
index 0000000..fdc9e56
--- /dev/null
+++ b/src/atomic_ops/sysdeps/gcc/hexagon.h
@@ -0,0 +1,95 @@
+/*
+ * 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"