re PR middle-end/82569 (failure in 177.mesa cpu2000 test case after r253530)

	PR middle-end/82569
	* tree-outof-ssa.h (always_initialized_rtx_for_ssa_name_p): Delete.
	* expr.c (expand_expr_real_1) <expand_decl_rtl>: Revert latest change.
	* loop-iv.c (iv_get_reaching_def): Likewise.
	* cfgexpand.c (expand_one_ssa_partition): Initialize the RTX if the 
	variable is promoted and the partition contains undefined values.

From-SVN: r254037

1 files changed, 7 insertions, 26 deletions

diff --git a/gcc/expr.c b/gcc/expr.c
index cdf7ca2..496d492 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -9912,43 +9912,24 @@ expand_expr_real_1 (tree exp, rtx target, machine_mode tmode,
 	  && GET_MODE (decl_rtl) != dmode)
 	{
 	  machine_mode pmode;
-	  bool always_initialized_rtx;
 
 	  /* Get the signedness to be used for this variable.  Ensure we get
 	     the same mode we got when the variable was declared.  */
 	  if (code != SSA_NAME)
-	    {
-	      pmode = promote_decl_mode (exp, &unsignedp);
-	      always_initialized_rtx = true;
-	    }
+	    pmode = promote_decl_mode (exp, &unsignedp);
 	  else if ((g = SSA_NAME_DEF_STMT (ssa_name))
 		   && gimple_code (g) == GIMPLE_CALL
 		   && !gimple_call_internal_p (g))
-	    {
-	      pmode = promote_function_mode (type, mode, &unsignedp,
-					    gimple_call_fntype (g), 2);
-	      always_initialized_rtx
-		= always_initialized_rtx_for_ssa_name_p (ssa_name);
-	    }
+	    pmode = promote_function_mode (type, mode, &unsignedp,
+					   gimple_call_fntype (g),
+					   2);
 	  else
-	    {
-	      pmode = promote_ssa_mode (ssa_name, &unsignedp);
-	      always_initialized_rtx
-		= always_initialized_rtx_for_ssa_name_p (ssa_name);
-	    }
-
+	    pmode = promote_ssa_mode (ssa_name, &unsignedp);
 	  gcc_assert (GET_MODE (decl_rtl) == pmode);
 
 	  temp = gen_lowpart_SUBREG (mode, decl_rtl);
-
-	  /* We cannot assume anything about an existing extension if the
-	     register may contain uninitialized bits.  */
-	  if (always_initialized_rtx)
-	    {
-	      SUBREG_PROMOTED_VAR_P (temp) = 1;
-	      SUBREG_PROMOTED_SET (temp, unsignedp);
-	    }
-
+	  SUBREG_PROMOTED_VAR_P (temp) = 1;
+	  SUBREG_PROMOTED_SET (temp, unsignedp);
 	  return temp;
 	}