Unify implementations of __builtin_mem_*_fence and __sync_synchronize.

	* builtins.c (expand_builtin_mem_thread_fence): Remove.
	(expand_builtin_mem_signal_fence): Remove.
	(expand_builtin_atomic_thread_fence): Use expand_mem_thread_fence.
	(expand_builtin_sync_synchronize): Likewise.
	(expand_builtin_atomic_signal_fence): Use expand_mem_signal_fence.
	* optabs.c (expand_asm_memory_barrier): Split out from
	expand_builtin_mem_signal_fence.
	(expand_mem_thread_fence): New, a combination of code from
	expand_builtin_mem_thread_fence and expand_builtin_sync_synchronize.
	(expand_mem_signal_fence): Moved and renamed from
	expand_builtin_mem_signal_fence.
	(expand_atomic_exchange): Use expand_mem_thread_fence.
	(expand_atomic_load, expand_atomic_store): Likewise.
	* expr.h, optabs.h: Update decls.

From-SVN: r181451

1 files changed, 5 insertions, 86 deletions

diff --git a/gcc/builtins.c b/gcc/builtins.c
index 9dc68cc..fe0260f 100644
--- a/gcc/builtins.c
+++ b/gcc/builtins.c
@@ -5672,23 +5672,6 @@ expand_builtin_atomic_is_lock_free (tree exp)
   return NULL_RTX;
 }
 
-/* This routine will either emit the mem_thread_fence pattern or issue a 
-   sync_synchronize to generate a fence for memory model MEMMODEL.  */
-
-#ifndef HAVE_mem_thread_fence
-# define HAVE_mem_thread_fence 0
-# define gen_mem_thread_fence(x) (gcc_unreachable (), NULL_RTX)
-#endif
-
-void
-expand_builtin_mem_thread_fence (enum memmodel model)
-{
-  if (HAVE_mem_thread_fence)
-    emit_insn (gen_mem_thread_fence (GEN_INT (model)));
-  else if (model != MEMMODEL_RELAXED)
-    expand_builtin_sync_synchronize ();
-}
-
 /* Expand the __atomic_thread_fence intrinsic:
    	void __atomic_thread_fence (enum memmodel)
    EXP is the CALL_EXPR.  */
@@ -5696,46 +5679,8 @@ expand_builtin_mem_thread_fence (enum memmodel model)
 static void
 expand_builtin_atomic_thread_fence (tree exp)
 {
-  enum memmodel model;
-  
-  model = get_memmodel (CALL_EXPR_ARG (exp, 0));
-  expand_builtin_mem_thread_fence (model);
-}
-
-/* This routine will either emit the mem_signal_fence pattern or issue a 
-   sync_synchronize to generate a fence for memory model MEMMODEL.  */
-
-#ifndef HAVE_mem_signal_fence
-# define HAVE_mem_signal_fence 0
-# define gen_mem_signal_fence(x) (gcc_unreachable (), NULL_RTX)
-#endif
-
-static void
-expand_builtin_mem_signal_fence (enum memmodel model)
-{
-  if (HAVE_mem_signal_fence)
-    emit_insn (gen_mem_signal_fence (GEN_INT (model)));
-  else if (model != MEMMODEL_RELAXED)
-    {
-      rtx asm_op, clob;
-
-      /* By default targets are coherent between a thread and the signal
-	 handler running on the same thread.  Thus this really becomes a
-	 compiler barrier, in that stores must not be sunk past
-	 (or raised above) a given point.  */
-
-      /* Generate asm volatile("" : : : "memory") as the memory barrier.  */
-      asm_op = gen_rtx_ASM_OPERANDS (VOIDmode, empty_string, empty_string, 0,
-				     rtvec_alloc (0), rtvec_alloc (0),
-				     rtvec_alloc (0), UNKNOWN_LOCATION);
-      MEM_VOLATILE_P (asm_op) = 1;
-
-      clob = gen_rtx_SCRATCH (VOIDmode);
-      clob = gen_rtx_MEM (BLKmode, clob);
-      clob = gen_rtx_CLOBBER (VOIDmode, clob);
-
-      emit_insn (gen_rtx_PARALLEL (VOIDmode, gen_rtvec (2, asm_op, clob)));
-    }
+  enum memmodel model = get_memmodel (CALL_EXPR_ARG (exp, 0));
+  expand_mem_thread_fence (model);
 }
 
 /* Expand the __atomic_signal_fence intrinsic:
@@ -5745,10 +5690,8 @@ expand_builtin_mem_signal_fence (enum memmodel model)
 static void
 expand_builtin_atomic_signal_fence (tree exp)
 {
-  enum memmodel model;
-
-  model = get_memmodel (CALL_EXPR_ARG (exp, 0));
-  expand_builtin_mem_signal_fence (model);
+  enum memmodel model = get_memmodel (CALL_EXPR_ARG (exp, 0));
+  expand_mem_signal_fence (model);
 }
 
 /* Expand the __sync_synchronize intrinsic.  */
@@ -5756,31 +5699,7 @@ expand_builtin_atomic_signal_fence (tree exp)
 static void
 expand_builtin_sync_synchronize (void)
 {
-  gimple x;
-  VEC (tree, gc) *v_clobbers;
-
-#ifdef HAVE_memory_barrier
-  if (HAVE_memory_barrier)
-    {
-      emit_insn (gen_memory_barrier ());
-      return;
-    }
-#endif
-
-  if (synchronize_libfunc != NULL_RTX)
-    {
-      emit_library_call (synchronize_libfunc, LCT_NORMAL, VOIDmode, 0);
-      return;
-    }
-
-  /* If no explicit memory barrier instruction is available, create an
-     empty asm stmt with a memory clobber.  */
-  v_clobbers = VEC_alloc (tree, gc, 1);
-  VEC_quick_push (tree, v_clobbers,
-		  tree_cons (NULL, build_string (6, "memory"), NULL));
-  x = gimple_build_asm_vec ("", NULL, NULL, v_clobbers, NULL);
-  gimple_asm_set_volatile (x, true);
-  expand_asm_stmt (x);
+  expand_mem_thread_fence (MEMMODEL_SEQ_CST);
 }