tree-outof-ssa.h (ssaexpand): Add partitions_for_undefined_values.

	* tree-outof-ssa.h (ssaexpand): Add partitions_for_undefined_values.
	(always_initialized_rtx_for_ssa_name_p): New predicate.
	* tree-outof-ssa.c (remove_ssa_form): Initialize new field of SA.
	(finish_out_of_ssa): Free new field of SA.
	* tree-ssa-coalesce.h (get_undefined_value_partitions): Declare.
	* tree-ssa-coalesce.c: Include tree-ssa.h.
	(get_parm_default_def_partitions): Remove extern keyword.
	(get_undefined_value_partitions): New function.
	* expr.c (expand_expr_real_1) <expand_decl_rtl>: For a SSA_NAME, do
	not set SUBREG_PROMOTED_VAR_P on the sub-register if it may contain
	uninitialized bits.
	* loop-iv.c (iv_get_reaching_def): Disqualify all subregs.

From-SVN: r253530

1 files changed, 27 insertions, 1 deletions

diff --git a/gcc/tree-ssa-coalesce.c b/gcc/tree-ssa-coalesce.c
index e166314..3938f06 100644
--- a/gcc/tree-ssa-coalesce.c
+++ b/gcc/tree-ssa-coalesce.c
@@ -28,6 +28,7 @@ along with GCC; see the file COPYING3.  If not see
 #include "memmodel.h"
 #include "tm_p.h"
 #include "ssa.h"
+#include "tree-ssa.h"
 #include "tree-pretty-print.h"
 #include "diagnostic-core.h"
 #include "dumpfile.h"
@@ -1923,7 +1924,7 @@ set_parm_default_def_partition (tree var, void *arg_)
 /* Allocate and return a bitmap that has a bit set for each partition
    that contains a default def for a parameter.  */
 
-extern bitmap
+bitmap
 get_parm_default_def_partitions (var_map map)
 {
   bitmap parm_default_def_parts = BITMAP_ALLOC (NULL);
@@ -1935,3 +1936,28 @@ get_parm_default_def_partitions (var_map map)
 
   return parm_default_def_parts;
 }
+
+/* Allocate and return a bitmap that has a bit set for each partition
+   that contains an undefined value.  */
+
+bitmap
+get_undefined_value_partitions (var_map map)
+{
+  bitmap undefined_value_parts = BITMAP_ALLOC (NULL);
+
+  for (unsigned int i = 1; i < num_ssa_names; i++)
+    {
+      tree var = ssa_name (i);
+      if (var
+	  && !virtual_operand_p (var)
+	  && !has_zero_uses (var)
+	  && ssa_undefined_value_p (var))
+	{
+	  const int p = var_to_partition (map, var);
+	  if (p != NO_PARTITION)
+	    bitmap_set_bit (undefined_value_parts, p);
+	}
+    }
+
+  return undefined_value_parts;
+}