1 files changed, 31 insertions, 36 deletions

diff --git a/gcc/var-tracking.c b/gcc/var-tracking.c
index bdd3bdee34e..cfcc839b96c 100644
--- a/gcc/var-tracking.c
+++ b/gcc/var-tracking.c
@@ -732,6 +732,7 @@ dv_is_decl_p (decl_or_value dv)
     case (int)PARM_DECL:
     case (int)RESULT_DECL:
     case (int)FUNCTION_DECL:
+    case (int)DEBUG_EXPR_DECL:
     case (int)COMPONENT_REF:
       return true;
 
@@ -2222,7 +2223,7 @@ dataflow_set_union (dataflow_set *dst, dataflow_set *src)
 
 /* Whether the value is currently being expanded.  */
 #define VALUE_RECURSED_INTO(x) \
-  (RTL_FLAG_CHECK1 ("VALUE_RECURSED_INTO", (x), VALUE)->used)
+  (RTL_FLAG_CHECK2 ("VALUE_RECURSED_INTO", (x), VALUE, DEBUG_EXPR)->used)
 /* Whether the value is in changed_variables hash table.  */
 #define VALUE_CHANGED(x) \
   (RTL_FLAG_CHECK1 ("VALUE_CHANGED", (x), VALUE)->frame_related)
@@ -4112,6 +4113,9 @@ track_expr_p (tree expr, bool need_rtl)
   rtx decl_rtl;
   tree realdecl;
 
+  if (TREE_CODE (expr) == DEBUG_EXPR_DECL)
+    return DECL_RTL_SET_P (expr);
+
   /* If EXPR is not a parameter or a variable do not track it.  */
   if (TREE_CODE (expr) != VAR_DECL && TREE_CODE (expr) != PARM_DECL)
     return 0;
@@ -6242,24 +6246,6 @@ delete_variable_part (dataflow_set *set, rtx loc, decl_or_value dv,
   slot = delete_slot_part (set, loc, slot, offset);
 }
 
-/* Wrap result in CONST:MODE if needed to preserve the mode.  */
-
-static rtx
-check_wrap_constant (enum machine_mode mode, rtx result)
-{
-  if (!result || GET_MODE (result) == mode)
-    return result;
-
-  if (dump_file && (dump_flags & TDF_DETAILS))
-    fprintf (dump_file, "  wrapping result in const to preserve mode %s\n",
-	     GET_MODE_NAME (mode));
-
-  result = wrap_constant (mode, result);
-  gcc_assert (GET_MODE (result) == mode);
-
-  return result;
-}
-
 /* Callback for cselib_expand_value, that looks for expressions
    holding the value in the var-tracking hash tables.  Return X for
    standard processing, anything else is to be used as-is.  */
@@ -6271,11 +6257,12 @@ vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
   decl_or_value dv;
   variable var;
   location_chain loc;
-  rtx result;
+  rtx result, subreg, xret;
 
-  if (GET_CODE (x) == SUBREG)
+  switch (GET_CODE (x))
     {
-      rtx subreg = SUBREG_REG (x);
+    case SUBREG:
+      subreg = SUBREG_REG (x);
 
       if (GET_CODE (SUBREG_REG (x)) != VALUE)
 	return x;
@@ -6297,22 +6284,31 @@ vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
 	result = gen_rtx_raw_SUBREG (GET_MODE (x), subreg, SUBREG_BYTE (x));
 
       return result;
-    }
 
-  if (GET_CODE (x) != VALUE)
-    return x;
+    case DEBUG_EXPR:
+      dv = dv_from_decl (DEBUG_EXPR_TREE_DECL (x));
+      xret = NULL;
+      break;
+
+    case VALUE:
+      dv = dv_from_value (x);
+      xret = x;
+      break;
+
+    default:
+      return x;
+    }
 
   if (VALUE_RECURSED_INTO (x))
-    return x;
+    return NULL;
 
-  dv = dv_from_value (x);
   var = (variable) htab_find_with_hash (vars, dv, dv_htab_hash (dv));
 
   if (!var)
-    return x;
+    return xret;
 
   if (var->n_var_parts == 0)
-    return x;
+    return xret;
 
   gcc_assert (var->n_var_parts == 1);
 
@@ -6323,7 +6319,6 @@ vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
     {
       result = cselib_expand_value_rtx_cb (loc->loc, regs, max_depth,
 					   vt_expand_loc_callback, vars);
-      result = check_wrap_constant (GET_MODE (loc->loc), result);
       if (result)
 	break;
     }
@@ -6332,7 +6327,7 @@ vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
   if (result)
     return result;
   else
-    return x;
+    return xret;
 }
 
 /* Expand VALUEs in LOC, using VARS as well as cselib's equivalence
@@ -6341,14 +6336,11 @@ vt_expand_loc_callback (rtx x, bitmap regs, int max_depth, void *data)
 static rtx
 vt_expand_loc (rtx loc, htab_t vars)
 {
-  rtx newloc;
-
   if (!MAY_HAVE_DEBUG_INSNS)
     return loc;
 
-  newloc = cselib_expand_value_rtx_cb (loc, scratch_regs, 5,
-				       vt_expand_loc_callback, vars);
-  loc = check_wrap_constant (GET_MODE (loc), newloc);
+  loc = cselib_expand_value_rtx_cb (loc, scratch_regs, 5,
+				    vt_expand_loc_callback, vars);
 
   if (loc && MEM_P (loc))
     loc = targetm.delegitimize_address (loc);
@@ -6382,6 +6374,9 @@ emit_note_insn_var_location (void **varp, void *data)
 
   decl = dv_as_decl (var->dv);
 
+  if (TREE_CODE (decl) == DEBUG_EXPR_DECL)
+    goto clear;
+
   gcc_assert (decl);
 
   complete = true;