dwarf2out.c: Include tree-pass.h and gimple.h.

	* dwarf2out.c: Include tree-pass.h and gimple.h.
	(loc_list_plus_const): New function.
	(loc_descriptor_from_tree_1): Rename to ...
	(loc_descriptor_from_tree): ... remove original.
	(loc_list_from_tree): New function.
	(add_AT_location_description): Accept location list.
	(tls_mem_loc_descriptor): Update call of loc_descriptor_from_tree.
	(concatn_mem_loc_descriptor): Remove.
	(mem_loc_descriptor): Handle CONCAT/CONCATN and VAR_LOCATION by
	returning NULL.
	(secname_for_decl): Move up.
	(hidden_reference_p): New function; break out from ...
	(loc_by_refernece): ... here; move up.
	(dw_loc_list): New function.
	(single_element_loc_list): New function.
	(single_element_loc_list_p): New function.
	(add_loc_descr_to_each): New function.
	(add_loc_list): New function.
	(loc_descr_from_tree): Make wraper of loc_list_from_tree.
	(loc_list_from_tree): Reroganized from loc_descr_from_tree;
	add diagnostics why expansion failed.
	(add_location_or_const_value_attribute): Support location lists.
	(add_bound_info): Likewise.
	(descr_info_loc): Update call of loc_descriptor_from_tree.
	(gen_variable_die): Work on location lists.
	* final.c (pass_final): Add dump file.
	* Makefile.in (dwarf2out.o): Add new dependencies.

From-SVN: r151807

gcc/ChangeLog

+2009-09-17  Jan Hubicka  <jh@suse.cz>
+
+	* dwarf2out.c: Include tree-pass.h and gimple.h.
+	(loc_list_plus_const): New function.
+	(loc_descriptor_from_tree_1): Rename to ...
+	(loc_descriptor_from_tree): ... remove original.
+	(loc_list_from_tree): New function.
+	(add_AT_location_description): Accept location list.
+	(tls_mem_loc_descriptor): Update call of loc_descriptor_from_tree.
+	(concatn_mem_loc_descriptor): Remove.
+	(mem_loc_descriptor): Handle CONCAT/CONCATN and VAR_LOCATION by
+	returning NULL.
+	(secname_for_decl): Move up.
+	(hidden_reference_p): New function; break out from ...
+	(loc_by_refernece): ... here; move up.
+	(dw_loc_list): New function.
+	(single_element_loc_list): New function.
+	(single_element_loc_list_p): New function.
+	(add_loc_descr_to_each): New function.
+	(add_loc_list): New function.
+	(loc_descr_from_tree): Make wraper of loc_list_from_tree.
+	(loc_list_from_tree): Reroganized from loc_descr_from_tree;
+	add diagnostics why expansion failed.
+	(add_location_or_const_value_attribute): Support location lists.
+	(add_bound_info): Likewise.
+	(descr_info_loc): Update call of loc_descriptor_from_tree.
+	(gen_variable_die): Work on location lists.
+	* final.c (pass_final): Add dump file.
+	* Makefile.in (dwarf2out.o): Add new dependencies.
+
 2009-09-17  Janis Johnson  <janis187@us.ibm.com>
 
 	PR c/41049

gcc/Makefile.in

@@ -2731,7 +2731,7 @@ dwarf2out.o : dwarf2out.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    output.h $(DIAGNOSTIC_H) $(REAL_H) hard-reg-set.h $(REGS_H) $(EXPR_H) \
    libfuncs.h $(TOPLEV_H) dwarf2out.h reload.h $(GGC_H) $(EXCEPT_H) dwarf2asm.h \
    $(TM_P_H) langhooks.h $(HASHTAB_H) gt-dwarf2out.h $(TARGET_H) $(CGRAPH_H) \
-   $(MD5_H) $(INPUT_H) $(FUNCTION_H) $(VARRAY_H)
+   $(MD5_H) $(INPUT_H) $(FUNCTION_H) $(VARRAY_H) $(GIMPLE_H) $(TREE_PASS_H)
 dwarf2asm.o : dwarf2asm.c $(CONFIG_H) $(SYSTEM_H) coretypes.h $(TM_H) \
    $(FLAGS_H) $(RTL_H) $(TREE_H) output.h dwarf2asm.h $(TM_P_H) $(GGC_H) \
    gt-dwarf2asm.h $(DWARF2_H) $(SPLAY_TREE_H) $(TARGET_H)

gcc/dwarf2out.c

@@ -89,6 +89,8 @@ along with GCC; see the file COPYING3.  If not see
 #include "hashtab.h"
 #include "cgraph.h"
 #include "input.h"
+#include "gimple.h"
+#include "tree-pass.h"
 
 #ifdef DWARF2_DEBUGGING_INFO
 static void dwarf2out_source_line (unsigned int, const char *, int, bool);
@@ -4655,6 +4657,16 @@ loc_descr_plus_const (dw_loc_descr_ref *list_head, HOST_WIDE_INT offset)
     }
 }
 
+/* Add a constant OFFSET to a location list.  */
+
+static void
+loc_list_plus_const (dw_loc_list_ref list_head, HOST_WIDE_INT offset)
+{
+  dw_loc_list_ref d;
+  for (d = list_head; d != NULL; d = d->dw_loc_next)
+    loc_descr_plus_const (&d->expr, offset);
+}
+
 /* Return the size of a location descriptor.  */
 
 static unsigned long
@@ -5938,8 +5950,8 @@ static dw_loc_descr_ref concat_loc_descriptor (rtx, rtx,
 					       enum var_init_status);
 static dw_loc_descr_ref loc_descriptor (rtx, enum machine_mode mode,
 					enum var_init_status);
-static dw_loc_descr_ref loc_descriptor_from_tree_1 (tree, int);
-static dw_loc_descr_ref loc_descriptor_from_tree (tree);
+static dw_loc_list_ref loc_list_from_tree (tree, int);
+static dw_loc_descr_ref loc_descriptor_from_tree (tree, int);
 static HOST_WIDE_INT ceiling (HOST_WIDE_INT, unsigned int);
 static tree field_type (const_tree);
 static unsigned int simple_type_align_in_bits (const_tree);
@@ -5947,7 +5959,7 @@ static unsigned int simple_decl_align_in_bits (const_tree);
 static unsigned HOST_WIDE_INT simple_type_size_in_bits (const_tree);
 static HOST_WIDE_INT field_byte_offset (const_tree);
 static void add_AT_location_description	(dw_die_ref, enum dwarf_attribute,
-					 dw_loc_descr_ref);
+					 dw_loc_list_ref);
 static void add_data_member_location_attribute (dw_die_ref, tree);
 static void add_const_value_attribute (dw_die_ref, rtx);
 static void insert_int (HOST_WIDE_INT, unsigned, unsigned char *);
@@ -10958,36 +10970,6 @@ is_based_loc (const_rtx rtl)
 	       && CONST_INT_P (XEXP (rtl, 1)))));
 }
 
-/* Return a descriptor that describes the concatenation of N locations
-   used to form the address of a memory location.  */
-
-static dw_loc_descr_ref
-concatn_mem_loc_descriptor (rtx concatn, enum machine_mode mode,
-			    enum var_init_status initialized)
-{
-  unsigned int i;
-  dw_loc_descr_ref cc_loc_result = NULL;
-  unsigned int n = XVECLEN (concatn, 0);
-
-  for (i = 0; i < n; ++i)
-    {
-      dw_loc_descr_ref ref;
-      rtx x = XVECEXP (concatn, 0, i);
-
-      ref = mem_loc_descriptor (x, mode, VAR_INIT_STATUS_INITIALIZED);
-      if (ref == NULL)
-	return NULL;
-
-      add_loc_descr (&cc_loc_result, ref);
-      add_loc_descr_op_piece (&cc_loc_result, GET_MODE_SIZE (GET_MODE (x)));
-    }
-
-  if (cc_loc_result && initialized == VAR_INIT_STATUS_UNINITIALIZED)
-    add_loc_descr (&cc_loc_result, new_loc_descr (DW_OP_GNU_uninit, 0, 0));
-
-  return cc_loc_result;
-}
-
 /* Try to handle TLS MEMs, for which mem_loc_descriptor on XEXP (mem, 0)
    failed.  */
 
@@ -11006,7 +10988,7 @@ tls_mem_loc_descriptor (rtx mem)
       || !DECL_THREAD_LOCAL_P (base))
     return NULL;
 
-  loc_result = loc_descriptor_from_tree_1 (MEM_EXPR (mem), 2);
+  loc_result = loc_descriptor_from_tree (MEM_EXPR (mem), 2);
   if (loc_result == NULL)
     return NULL;
 
@@ -11016,6 +10998,26 @@ tls_mem_loc_descriptor (rtx mem)
   return loc_result;
 }
 
+/* Output debug info about reason why we failed to expand expression as dwarf
+   expression.  */
+
+static void
+expansion_failed (tree expr, rtx rtl, char const *reason)
+{
+  if (dump_file && (dump_flags & TDF_DETAILS))
+    {
+      fprintf (dump_file, "Failed to expand as dwarf: ");
+      if (expr)
+	print_generic_expr (dump_file, expr, dump_flags);
+      if (rtl)
+	{
+	  fprintf (dump_file, "\n");
+	  print_rtl (dump_file, rtl);
+	}
+      fprintf (dump_file, "\nReason: %s\n", reason);
+    }
+}
+
 /* The following routine converts the RTL for a variable or parameter
    (resident in memory) into an equivalent Dwarf representation of a
    mechanism for getting the address of that same variable onto the top of a
@@ -11163,7 +11165,11 @@ mem_loc_descriptor (rtx rtl, enum machine_mode mode,
 	     FIXME: might try to use DW_OP_const_value here, though
 	     DW_OP_piece complicates it.  */
 	  if (!marked)
-	    return 0;
+	    {
+	      expansion_failed (NULL_TREE, rtl,
+				"Constant was removed from constant pool.\n");
+	      return 0;
+	    }
 	}
 
       if (GET_CODE (rtl) == SYMBOL_REF
@@ -11193,6 +11199,14 @@ mem_loc_descriptor (rtx rtl, enum machine_mode mode,
       VEC_safe_push (rtx, gc, used_rtx_array, rtl);
       break;
 
+    case CONCAT:
+    case CONCATN:
+    case VAR_LOCATION:
+      expansion_failed (NULL_TREE, rtl,
+			"CONCAT/CONCATN/VAR_LOCATION is handled only by loc_descriptor");
+      gcc_unreachable ();
+      return 0;
+
     case PRE_MODIFY:
       /* Extract the PLUS expression nested inside and fall into
 	 PLUS code below.  */
@@ -11322,11 +11336,6 @@ mem_loc_descriptor (rtx rtl, enum machine_mode mode,
       mem_loc_result = int_loc_descriptor (INTVAL (rtl));
       break;
 
-    case CONCATN:
-      mem_loc_result = concatn_mem_loc_descriptor (rtl, mode,
-						   VAR_INIT_STATUS_INITIALIZED);
-      break;
-
     case EQ:
       op = DW_OP_eq;
       goto do_scompare;
@@ -11972,16 +11981,310 @@ loc_descriptor (rtx rtl, enum machine_mode mode,
   return loc_result;
 }
 
-/* Similar, but generate the descriptor from trees instead of rtl.  This comes
-   up particularly with variable length arrays.  WANT_ADDRESS is 2 if this is
-   a top-level invocation of loc_descriptor_from_tree; is 1 if this is not a
-   top-level invocation, and we require the address of LOC; is 0 if we require
-   the value of LOC.  */
+/* We need to figure out what section we should use as the base for the
+   address ranges where a given location is valid.
+   1. If this particular DECL has a section associated with it, use that.
+   2. If this function has a section associated with it, use that.
+   3. Otherwise, use the text section.
+   XXX: If you split a variable across multiple sections, we won't notice.  */
+
+static const char *
+secname_for_decl (const_tree decl)
+{
+  const char *secname;
+
+  if (VAR_OR_FUNCTION_DECL_P (decl) && DECL_SECTION_NAME (decl))
+    {
+      tree sectree = DECL_SECTION_NAME (decl);
+      secname = TREE_STRING_POINTER (sectree);
+    }
+  else if (current_function_decl && DECL_SECTION_NAME (current_function_decl))
+    {
+      tree sectree = DECL_SECTION_NAME (current_function_decl);
+      secname = TREE_STRING_POINTER (sectree);
+    }
+  else if (cfun && in_cold_section_p)
+    secname = crtl->subsections.cold_section_label;
+  else
+    secname = text_section_label;
+
+  return secname;
+}
+
+/* Return true when DECL_BY_REFERENCE is defined and set for DECL.  */
+
+static bool
+decl_by_reference_p (tree decl)
+{
+  return ((TREE_CODE (decl) == PARM_DECL || TREE_CODE (decl) == RESULT_DECL
+  	   || TREE_CODE (decl) == VAR_DECL)
+	  && DECL_BY_REFERENCE (decl));
+}
+
+
+/* Dereference a location expression LOC if DECL is passed by invisible
+   reference.  */
 
 static dw_loc_descr_ref
-loc_descriptor_from_tree_1 (tree loc, int want_address)
+loc_by_reference (dw_loc_descr_ref loc, tree decl)
+{
+  HOST_WIDE_INT size;
+  enum dwarf_location_atom op;
+
+  if (loc == NULL)
+    return NULL;
+
+  if (!decl_by_reference_p (decl))
+    return loc;
+
+  /* If loc is DW_OP_reg{0...31,x}, don't add DW_OP_deref, instead
+     change it into corresponding DW_OP_breg{0...31,x} 0.  Then the
+     location expression is considered to be address of a memory location,
+     rather than the register itself.  */
+  if (((loc->dw_loc_opc >= DW_OP_reg0 && loc->dw_loc_opc <= DW_OP_reg31)
+       || loc->dw_loc_opc == DW_OP_regx)
+      && (loc->dw_loc_next == NULL
+	  || (loc->dw_loc_next->dw_loc_opc == DW_OP_GNU_uninit
+	      && loc->dw_loc_next->dw_loc_next == NULL)))
+    {
+      if (loc->dw_loc_opc == DW_OP_regx)
+	{
+	  loc->dw_loc_opc = DW_OP_bregx;
+	  loc->dw_loc_oprnd2.v.val_int = 0;
+	}
+      else
+	{
+	  loc->dw_loc_opc
+	    = (enum dwarf_location_atom)
+	      (loc->dw_loc_opc + (DW_OP_breg0 - DW_OP_reg0));
+	  loc->dw_loc_oprnd1.v.val_int = 0;
+	}
+      return loc;
+    }
+
+  size = int_size_in_bytes (TREE_TYPE (decl));
+  if (size > DWARF2_ADDR_SIZE || size == -1)
+    return 0;
+  else if (size == DWARF2_ADDR_SIZE)
+    op = DW_OP_deref;
+  else
+    op = DW_OP_deref_size;
+  add_loc_descr (&loc, new_loc_descr (op, size, 0));
+  return loc;
+}
+
+/* Return dwarf representation of location list representing for
+   LOC_LIST of DECL.  */
+
+static dw_loc_list_ref
+dw_loc_list (var_loc_list * loc_list, tree decl, bool toplevel)
+{
+  const char *endname, *secname;
+  dw_loc_list_ref list;
+  rtx varloc;
+  enum var_init_status initialized;
+  struct var_loc_node *node;
+  dw_loc_descr_ref descr;
+  char label_id[MAX_ARTIFICIAL_LABEL_BYTES];
+
+  bool by_reference = decl_by_reference_p (decl);
+
+  /* Now that we know what section we are using for a base,
+     actually construct the list of locations.
+     The first location information is what is passed to the
+     function that creates the location list, and the remaining
+     locations just get added on to that list.
+     Note that we only know the start address for a location
+     (IE location changes), so to build the range, we use
+     the range [current location start, next location start].
+     This means we have to special case the last node, and generate
+     a range of [last location start, end of function label].  */
+
+  node = loc_list->first;
+  varloc = NOTE_VAR_LOCATION (node->var_loc_note);
+  secname = secname_for_decl (decl);
+
+  if (NOTE_VAR_LOCATION_LOC (node->var_loc_note))
+    initialized = NOTE_VAR_LOCATION_STATUS (node->var_loc_note);
+  else
+    initialized = VAR_INIT_STATUS_INITIALIZED;
+
+  if (!toplevel || by_reference)
+    {
+      gcc_assert (GET_CODE (varloc) == VAR_LOCATION);
+      /* Single part.  */
+      if (GET_CODE (XEXP (varloc, 1)) != PARALLEL)
+	descr = loc_by_reference (mem_loc_descriptor (XEXP (XEXP (varloc, 1), 0),
+						      TYPE_MODE (TREE_TYPE (decl)),
+						      initialized),
+				  decl);
+      else
+	descr = NULL;
+    }
+  else
+    descr = loc_descriptor (varloc, DECL_MODE (decl), initialized);
+
+  if (!current_function_decl)
+    endname = text_end_label;
+  else
+    {
+      ASM_GENERATE_INTERNAL_LABEL (label_id, FUNC_END_LABEL,
+				   current_function_funcdef_no);
+      endname = ggc_strdup (label_id);
+    }
+  list = new_loc_list (descr, node->label, node->next ? node->next->label : endname, secname, 1);
+  node = node->next;
+
+  if (!node)
+    return NULL;
+
+  for (; node->next; node = node->next)
+    if (NOTE_VAR_LOCATION_LOC (node->var_loc_note) != NULL_RTX)
+      {
+	/* The variable has a location between NODE->LABEL and
+	   NODE->NEXT->LABEL.  */
+	enum var_init_status initialized =
+	  NOTE_VAR_LOCATION_STATUS (node->var_loc_note);
+	varloc = NOTE_VAR_LOCATION (node->var_loc_note);
+	if (!toplevel || by_reference)
+	  {
+	    gcc_assert (GET_CODE (varloc) == VAR_LOCATION);
+	    /* Single part.  */
+	    if (GET_CODE (XEXP (varloc, 1)) != PARALLEL)
+	      descr = mem_loc_descriptor (XEXP (XEXP (varloc, 1), 0),
+	      				  TYPE_MODE (TREE_TYPE (decl)), initialized);
+	    else
+	      descr = NULL;
+	    descr = loc_by_reference (descr, decl);
+	  }
+	else
+	  descr = loc_descriptor (varloc, DECL_MODE (decl), initialized);
+	add_loc_descr_to_loc_list (&list, descr,
+				   node->label, node->next->label, secname);
+      }
+
+  /* If the variable has a location at the last label
+     it keeps its location until the end of function.  */
+  if (NOTE_VAR_LOCATION_LOC (node->var_loc_note) != NULL_RTX)
+    {
+      enum var_init_status initialized =
+	NOTE_VAR_LOCATION_STATUS (node->var_loc_note);
+
+      varloc = NOTE_VAR_LOCATION (node->var_loc_note);
+      if (!toplevel || by_reference)
+	{
+	  gcc_assert (GET_CODE (varloc) == VAR_LOCATION);
+	  /* Single part.  */
+	  if (GET_CODE (XEXP (varloc, 1)) != PARALLEL)
+	    descr = mem_loc_descriptor (XEXP (XEXP (varloc, 1), 0),
+	    				TYPE_MODE (TREE_TYPE (decl)), initialized);
+	  else
+	    descr = NULL;
+	  descr = loc_by_reference (descr, decl);
+	}
+      else
+	descr = loc_descriptor (varloc, DECL_MODE (decl), initialized);
+      add_loc_descr_to_loc_list (&list, descr, node->label, endname, secname);
+    }
+  return list;
+}
+
+/* Return single element location list containing loc descr REF.  */
+
+static dw_loc_list_ref
+single_element_loc_list (dw_loc_descr_ref ref)
+{
+  return new_loc_list (ref, NULL, NULL, NULL, 0);
+}
+
+/* Return if the loc_list has only single element and thus can be represented
+   as location description.   */
+
+static bool
+single_element_loc_list_p (dw_loc_list_ref list)
 {
-  dw_loc_descr_ref ret, ret1;
+  return (!list->dw_loc_next && !list->begin && !list->end);
+}
+
+/* To each location in list LIST add loc descr REF.  */
+
+static void
+add_loc_descr_to_each (dw_loc_list_ref list, dw_loc_descr_ref ref)
+{
+  dw_loc_descr_ref copy;
+  add_loc_descr (&list->expr, ref);
+  list = list->dw_loc_next;
+  while (list)
+    {
+      copy = GGC_CNEW (dw_loc_descr_node);
+      memcpy (copy, ref, sizeof (dw_loc_descr_node));
+      add_loc_descr (&list->expr, copy);
+      while (copy->dw_loc_next)
+	{
+	  dw_loc_descr_ref new_copy = GGC_CNEW (dw_loc_descr_node);
+	  memcpy (new_copy, copy->dw_loc_next, sizeof (dw_loc_descr_node));
+	  copy->dw_loc_next = new_copy;
+	  copy = new_copy;
+	}
+      list = list->dw_loc_next;
+    }
+}
+
+/* Given two lists RET and LIST
+   produce location list that is result of adding expression in LIST
+   to expression in RET on each possition in program.
+   Might be destructive on both RET and LIST.
+
+   TODO: We handle only simple cases of RET or LIST having at most one
+   element. General case would inolve sorting the lists in program order
+   and merging them that will need some additional work.  
+   Adding that will improve quality of debug info especially for SRA-ed
+   structures.  */
+
+static void
+add_loc_list (dw_loc_list_ref *ret, dw_loc_list_ref list)
+{
+  if (!list)
+    return;
+  if (!*ret)
+    {
+      *ret = list;
+      return;
+    }
+  if (!list->dw_loc_next)
+    {
+      add_loc_descr_to_each (*ret, list->expr);
+      return;
+    }
+  if (!(*ret)->dw_loc_next)
+    {
+      add_loc_descr_to_each (list, (*ret)->expr);
+      *ret = list;
+      return;
+    }
+  expansion_failed (NULL_TREE, NULL_RTX,
+		    "Don't know how to merge two non-trivial"
+		    " location lists.\n");
+  *ret = NULL;
+  return;
+}
+
+/* Generate Dwarf location list representing LOC.
+   If WANT_ADDRESS is false, expression computing LOC will be computed
+   If WANT_ADDRESS is 1, expression computing address of LOC will be returned
+   if WANT_ADDRESS is 2, expression computing address useable in location
+     will be returned (i.e. DW_OP_reg can be used
+     to refer to register values) 
+   TODO: Dwarf4 adds types to the stack machine that ought to be used here
+   DW_OP_stack_value will help in cases where we fail to find address of the
+   expression.
+ */
+
+static dw_loc_list_ref
+loc_list_from_tree (tree loc, int want_address)
+{
+  dw_loc_descr_ref ret = NULL, ret1 = NULL;
+  dw_loc_list_ref list_ret = NULL, list_ret1 = NULL;
   int have_address = 0;
   enum dwarf_location_atom op;
 
@@ -11992,6 +12295,7 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
   switch (TREE_CODE (loc))
     {
     case ERROR_MARK:
+      expansion_failed (loc, NULL_RTX, "ERROR_MARK");
       return 0;
 
     case PLACEHOLDER_EXPR:
@@ -11999,25 +12303,32 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 	 position of other fields.  We don't try to encode this here.  The
 	 only user of this is Ada, which encodes the needed information using
 	 the names of types.  */
+      expansion_failed (loc, NULL_RTX, "PLACEHOLDER_EXPR");
       return 0;
 
     case CALL_EXPR:
+      expansion_failed (loc, NULL_RTX, "CALL_EXPR");
+      /* There are no opcodes for these operations.  */
       return 0;
 
     case PREINCREMENT_EXPR:
     case PREDECREMENT_EXPR:
     case POSTINCREMENT_EXPR:
     case POSTDECREMENT_EXPR:
+      expansion_failed (loc, NULL_RTX, "PRE/POST INDCREMENT/DECREMENT");
       /* There are no opcodes for these operations.  */
       return 0;
 
     case ADDR_EXPR:
       /* If we already want an address, there's nothing we can do.  */
       if (want_address)
-	return 0;
+	{
+	  expansion_failed (loc, NULL_RTX, "need address of ADDR_EXPR");
+	  return 0;
+	}
 
       /* Otherwise, process the argument and look for the address.  */
-      return loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 1);
+      return loc_list_from_tree (TREE_OPERAND (loc, 0), 1);
 
     case VAR_DECL:
       if (DECL_THREAD_LOCAL_P (loc))
@@ -12030,7 +12341,7 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 	  if (targetm.have_tls)
 	    {
 	      /* If this is not defined, we have no way to emit the
-	         data.  */
+		 data.  */
 	      if (!targetm.asm_out.output_dwarf_dtprel)
 		return 0;
 
@@ -12077,17 +12388,24 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 
     case PARM_DECL:
       if (DECL_HAS_VALUE_EXPR_P (loc))
-	return loc_descriptor_from_tree_1 (DECL_VALUE_EXPR (loc),
-					   want_address);
+	return loc_list_from_tree (DECL_VALUE_EXPR (loc),
+					      want_address);
       /* FALLTHRU */
 
     case RESULT_DECL:
     case FUNCTION_DECL:
       {
 	rtx rtl = rtl_for_decl_location (loc);
+	var_loc_list *loc_list = lookup_decl_loc (loc);
 
-	if (rtl == NULL_RTX)
-	  return 0;
+	if (loc_list && loc_list->first
+	    && (list_ret = dw_loc_list (loc_list, loc, want_address == 2)))
+	  have_address = 1;
+	else if (rtl == NULL_RTX)
+	  {
+	    expansion_failed (loc, NULL_RTX, "DECL has no RTL");
+	    return 0;
+	  }
 	else if (CONST_INT_P (rtl))
 	  {
 	    HOST_WIDE_INT val = INTVAL (rtl);
@@ -12096,7 +12414,10 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 	    ret = int_loc_descriptor (val);
 	  }
 	else if (GET_CODE (rtl) == CONST_STRING)
-	  return 0;
+	  {
+	    expansion_failed (loc, NULL_RTX, "CONST_STRING");
+	    return 0;
+	  }
 	else if (CONSTANT_P (rtl))
 	  {
 	    ret = new_loc_descr (DW_OP_addr, 0, 0);
@@ -12109,33 +12430,41 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 
 	    /* Certain constructs can only be represented at top-level.  */
 	    if (want_address == 2)
-	      return loc_descriptor (rtl, VOIDmode,
-				     VAR_INIT_STATUS_INITIALIZED);
-
-	    mode = GET_MODE (rtl);
-	    if (MEM_P (rtl))
 	      {
-		rtl = XEXP (rtl, 0);
+		ret = loc_descriptor (rtl, VOIDmode,
+				      VAR_INIT_STATUS_INITIALIZED);
 		have_address = 1;
 	      }
-	    ret = mem_loc_descriptor (rtl, mode, VAR_INIT_STATUS_INITIALIZED);
+	    else
+	      {
+		mode = GET_MODE (rtl);
+		if (MEM_P (rtl))
+		  {
+		    rtl = XEXP (rtl, 0);
+		    have_address = 1;
+		  }
+		ret = mem_loc_descriptor (rtl, mode, VAR_INIT_STATUS_INITIALIZED);
+	      }
+	    if (!ret)
+	      expansion_failed (loc, rtl,
+				"failed to produce loc descriptor for rtl");
 	  }
       }
       break;
 
     case INDIRECT_REF:
-      ret = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 0);
+      list_ret = loc_list_from_tree (TREE_OPERAND (loc, 0), 0);
       have_address = 1;
       break;
 
     case COMPOUND_EXPR:
-      return loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 1), want_address);
+      return loc_list_from_tree (TREE_OPERAND (loc, 1), want_address);
 
     CASE_CONVERT:
     case VIEW_CONVERT_EXPR:
     case SAVE_EXPR:
     case MODIFY_EXPR:
-      return loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), want_address);
+      return loc_list_from_tree (TREE_OPERAND (loc, 0), want_address);
 
     case COMPONENT_REF:
     case BIT_FIELD_REF:
@@ -12151,26 +12480,35 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 	obj = get_inner_reference (loc, &bitsize, &bitpos, &offset, &mode,
 				   &unsignedp, &volatilep, false);
 
-	if (obj == loc)
-	  return 0;
+	gcc_assert (obj != loc);
 
-	ret = loc_descriptor_from_tree_1 (obj, 1);
-	if (ret == 0
-	    || bitpos % BITS_PER_UNIT != 0 || bitsize % BITS_PER_UNIT != 0)
+	list_ret = loc_list_from_tree (obj, 1);
+	if (list_ret == 0)
 	  return 0;
+	if (bitpos % BITS_PER_UNIT != 0 || bitsize % BITS_PER_UNIT != 0)
+	  {
+	    expansion_failed (loc, NULL_RTX,
+			      "bitfield access");
+	    return 0;
+	  }
 
 	if (offset != NULL_TREE)
 	  {
 	    /* Variable offset.  */
-	    ret1 = loc_descriptor_from_tree_1 (offset, 0);
-	    if (ret1 == 0)
+	    list_ret1 = loc_list_from_tree (offset, 0);
+	    if (list_ret1 == 0)
 	      return 0;
-	    add_loc_descr (&ret, ret1);
-	    add_loc_descr (&ret, new_loc_descr (DW_OP_plus, 0, 0));
+	    add_loc_list (&list_ret, list_ret1);
+	    if (!list_ret)
+	      return 0;
+	    add_loc_descr_to_each (list_ret, new_loc_descr (DW_OP_plus, 0, 0));
 	  }
 
 	bytepos = bitpos / BITS_PER_UNIT;
-	loc_descr_plus_const (&ret, bytepos);
+	if (bytepos > 0)
+	  add_loc_descr_to_each (list_ret, new_loc_descr (DW_OP_plus_uconst, bytepos, 0));
+	else if (bytepos < 0)
+	  loc_list_plus_const (list_ret, bytepos); 
 
 	have_address = 1;
 	break;
@@ -12180,7 +12518,11 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
       if (host_integerp (loc, 0))
 	ret = int_loc_descriptor (tree_low_cst (loc, 0));
       else
-	return 0;
+	{
+	  expansion_failed (loc, NULL_RTX,
+			    "Integer operand is not host integer");
+	  return 0;
+	}
       break;
 
     case CONSTRUCTOR:
@@ -12250,11 +12592,11 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
       if (TREE_CODE (TREE_OPERAND (loc, 1)) == INTEGER_CST
 	  && host_integerp (TREE_OPERAND (loc, 1), 0))
 	{
-	  ret = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 0);
-	  if (ret == 0)
+	  list_ret = loc_list_from_tree (TREE_OPERAND (loc, 0), 0);
+	  if (list_ret == 0)
 	    return 0;
 
-	  loc_descr_plus_const (&ret, tree_low_cst (TREE_OPERAND (loc, 1), 0));
+	  loc_list_plus_const (list_ret, tree_low_cst (TREE_OPERAND (loc, 1), 0));
 	  break;
 	}
 
@@ -12298,13 +12640,15 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
       goto do_binop;
 
     do_binop:
-      ret = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 0);
-      ret1 = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 1), 0);
-      if (ret == 0 || ret1 == 0)
+      list_ret = loc_list_from_tree (TREE_OPERAND (loc, 0), 0);
+      list_ret1 = loc_list_from_tree (TREE_OPERAND (loc, 1), 0);
+      if (list_ret == 0 || list_ret1 == 0)
 	return 0;
 
-      add_loc_descr (&ret, ret1);
-      add_loc_descr (&ret, new_loc_descr (op, 0, 0));
+      add_loc_list (&list_ret, list_ret1);
+      if (list_ret == 0)
+	return 0;
+      add_loc_descr_to_each (list_ret, new_loc_descr (op, 0, 0));
       break;
 
     case TRUTH_NOT_EXPR:
@@ -12321,11 +12665,11 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
       goto do_unop;
 
     do_unop:
-      ret = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 0);
-      if (ret == 0)
+      list_ret = loc_list_from_tree (TREE_OPERAND (loc, 0), 0);
+      if (list_ret == 0)
 	return 0;
 
-      add_loc_descr (&ret, new_loc_descr (op, 0, 0));
+      add_loc_descr_to_each (list_ret, new_loc_descr (op, 0, 0));
       break;
 
     case MIN_EXPR:
@@ -12345,29 +12689,29 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
     case COND_EXPR:
       {
 	dw_loc_descr_ref lhs
-	  = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 1), 0);
-	dw_loc_descr_ref rhs
-	  = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 2), 0);
+	  = loc_descriptor_from_tree (TREE_OPERAND (loc, 1), 0);
+	dw_loc_list_ref rhs
+	  = loc_list_from_tree (TREE_OPERAND (loc, 2), 0);
 	dw_loc_descr_ref bra_node, jump_node, tmp;
 
-	ret = loc_descriptor_from_tree_1 (TREE_OPERAND (loc, 0), 0);
-	if (ret == 0 || lhs == 0 || rhs == 0)
+	list_ret = loc_list_from_tree (TREE_OPERAND (loc, 0), 0);
+	if (list_ret == 0 || lhs == 0 || rhs == 0)
 	  return 0;
 
 	bra_node = new_loc_descr (DW_OP_bra, 0, 0);
-	add_loc_descr (&ret, bra_node);
+	add_loc_descr_to_each (list_ret, bra_node);
 
-	add_loc_descr (&ret, rhs);
+	add_loc_list (&list_ret, rhs);
 	jump_node = new_loc_descr (DW_OP_skip, 0, 0);
-	add_loc_descr (&ret, jump_node);
+	add_loc_descr_to_each (list_ret, jump_node);
 
-	add_loc_descr (&ret, lhs);
+	add_loc_descr_to_each (list_ret, lhs);
 	bra_node->dw_loc_oprnd1.val_class = dw_val_class_loc;
 	bra_node->dw_loc_oprnd1.v.val_loc = lhs;
 
 	/* ??? Need a node to point the skip at.  Use a nop.  */
 	tmp = new_loc_descr (DW_OP_nop, 0, 0);
-	add_loc_descr (&ret, tmp);
+	add_loc_descr_to_each (list_ret, tmp);
 	jump_node->dw_loc_oprnd1.val_class = dw_val_class_loc;
 	jump_node->dw_loc_oprnd1.v.val_loc = tmp;
       }
@@ -12381,7 +12725,11 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 	 up, for instance, with the C STMT_EXPR.  */
       if ((unsigned int) TREE_CODE (loc)
 	  >= (unsigned int) LAST_AND_UNUSED_TREE_CODE)
-	return 0;
+	{
+	  expansion_failed (loc, NULL_RTX,
+			    "language specific tree node");
+	  return 0;
+	}
 
 #ifdef ENABLE_CHECKING
       /* Otherwise this is a generic code; we should just lists all of
@@ -12394,32 +12742,60 @@ loc_descriptor_from_tree_1 (tree loc, int want_address)
 #endif
     }
 
+  if (!ret && !list_ret)
+    return 0;
+
   /* Show if we can't fill the request for an address.  */
   if (want_address && !have_address)
-    return 0;
+    {
+      expansion_failed (loc, NULL_RTX,
+			"Want address and only have value");
+      return 0;
+    }
+
+  gcc_assert (!ret || !list_ret);
 
   /* If we've got an address and don't want one, dereference.  */
-  if (!want_address && have_address && ret)
+  if (!want_address && have_address)
     {
       HOST_WIDE_INT size = int_size_in_bytes (TREE_TYPE (loc));
 
       if (size > DWARF2_ADDR_SIZE || size == -1)
-	return 0;
+	{
+	  expansion_failed (loc, NULL_RTX,
+			    "DWARF address size mismatch");
+	  return 0;
+	}
       else if (size == DWARF2_ADDR_SIZE)
 	op = DW_OP_deref;
       else
 	op = DW_OP_deref_size;
 
-      add_loc_descr (&ret, new_loc_descr (op, size, 0));
+      if (ret)
+	add_loc_descr (&ret, new_loc_descr (op, size, 0));
+      else
+	add_loc_descr_to_each (list_ret, new_loc_descr (op, size, 0));
     }
+  if (ret)
+    list_ret = single_element_loc_list (ret);
 
-  return ret;
+  return list_ret;
 }
 
-static inline dw_loc_descr_ref
-loc_descriptor_from_tree (tree loc)
+/* Same as above but return only single location expression.  */
+static dw_loc_descr_ref
+loc_descriptor_from_tree (tree loc, int want_address)
 {
-  return loc_descriptor_from_tree_1 (loc, 2);
+  dw_loc_list_ref ret = loc_list_from_tree (loc, want_address);
+  if (!ret)
+    return NULL;
+  if (ret->dw_loc_next)
+    {
+      expansion_failed (loc, NULL_RTX,
+			"Location list where only loc descriptor needed");
+      return NULL;
+    }
+  return ret->expr;
 }
 
 /* Given a value, round it up to the lowest multiple of `boundary'
@@ -12529,9 +12905,9 @@ field_byte_offset (const_tree decl)
       field_size_tree = DECL_SIZE (decl);
 
       /* The size could be unspecified if there was an error, or for
-         a flexible array member.  */
+	 a flexible array member.  */
       if (!field_size_tree)
-        field_size_tree = bitsize_zero_node;
+	field_size_tree = bitsize_zero_node;
 
       /* If the size of the field is not constant, use the type size.  */
       if (host_integerp (field_size_tree, 1))
@@ -12626,10 +13002,14 @@ field_byte_offset (const_tree decl)
 
 static inline void
 add_AT_location_description (dw_die_ref die, enum dwarf_attribute attr_kind,
-			     dw_loc_descr_ref descr)
+			     dw_loc_list_ref descr)
 {
-  if (descr != 0)
-    add_AT_loc (die, attr_kind, descr);
+  if (descr == 0)
+    return;
+  if (single_element_loc_list_p (descr))
+    add_AT_loc (die, attr_kind, descr->expr);
+  else
+    add_AT_loc_list (die, attr_kind, descr);
 }
 
 /* Attach the specialized form of location attribute used for data members of
@@ -13267,36 +13647,6 @@ rtl_for_decl_location (tree decl)
   return rtl;
 }
 
-/* We need to figure out what section we should use as the base for the
-   address ranges where a given location is valid.
-   1. If this particular DECL has a section associated with it, use that.
-   2. If this function has a section associated with it, use that.
-   3. Otherwise, use the text section.
-   XXX: If you split a variable across multiple sections, we won't notice.  */
-
-static const char *
-secname_for_decl (const_tree decl)
-{
-  const char *secname;
-
-  if (VAR_OR_FUNCTION_DECL_P (decl) && DECL_SECTION_NAME (decl))
-    {
-      tree sectree = DECL_SECTION_NAME (decl);
-      secname = TREE_STRING_POINTER (sectree);
-    }
-  else if (current_function_decl && DECL_SECTION_NAME (current_function_decl))
-    {
-      tree sectree = DECL_SECTION_NAME (current_function_decl);
-      secname = TREE_STRING_POINTER (sectree);
-    }
-  else if (cfun && in_cold_section_p)
-    secname = crtl->subsections.cold_section_label;
-  else
-    secname = text_section_label;
-
-  return secname;
-}
-
 /* Check whether decl is a Fortran COMMON symbol.  If not, NULL_TREE is
    returned.  If so, the decl for the COMMON block is returned, and the
    value is the offset into the common block for the symbol.  */
@@ -13347,60 +13697,6 @@ fortran_common (tree decl, HOST_WIDE_INT *value)
   return cvar;
 }
 
-/* Dereference a location expression LOC if DECL is passed by invisible
-   reference.  */
-
-static dw_loc_descr_ref
-loc_by_reference (dw_loc_descr_ref loc, tree decl)
-{
-  HOST_WIDE_INT size;
-  enum dwarf_location_atom op;
-
-  if (loc == NULL)
-    return NULL;
-
-  if ((TREE_CODE (decl) != PARM_DECL
-       && TREE_CODE (decl) != RESULT_DECL
-       && TREE_CODE (decl) != VAR_DECL)
-      || !DECL_BY_REFERENCE (decl))
-    return loc;
-
-  /* If loc is DW_OP_reg{0...31,x}, don't add DW_OP_deref, instead
-     change it into corresponding DW_OP_breg{0...31,x} 0.  Then the
-     location expression is considered to be address of a memory location,
-     rather than the register itself.  */
-  if (((loc->dw_loc_opc >= DW_OP_reg0 && loc->dw_loc_opc <= DW_OP_reg31)
-       || loc->dw_loc_opc == DW_OP_regx)
-      && (loc->dw_loc_next == NULL
-	  || (loc->dw_loc_next->dw_loc_opc == DW_OP_GNU_uninit
-	      && loc->dw_loc_next->dw_loc_next == NULL)))
-    {
-      if (loc->dw_loc_opc == DW_OP_regx)
-	{
-	  loc->dw_loc_opc = DW_OP_bregx;
-	  loc->dw_loc_oprnd2.v.val_int = 0;
-	}
-      else
-	{
-	  loc->dw_loc_opc
-	    = (enum dwarf_location_atom)
-	      (loc->dw_loc_opc + (DW_OP_breg0 - DW_OP_reg0));
-	  loc->dw_loc_oprnd1.v.val_int = 0;
-	}
-      return loc;
-    }
-
-  size = int_size_in_bytes (TREE_TYPE (decl));
-  if (size > DWARF2_ADDR_SIZE || size == -1)
-    return 0;
-  else if (size == DWARF2_ADDR_SIZE)
-    op = DW_OP_deref;
-  else
-    op = DW_OP_deref_size;
-  add_loc_descr (&loc, new_loc_descr (op, size, 0));
-  return loc;
-}
-
 /* Generate *either* a DW_AT_location attribute or else a DW_AT_const_value
    data attribute for a variable or a parameter.  We generate the
    DW_AT_const_value attribute only in those cases where the given variable
@@ -13418,6 +13714,7 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
 {
   rtx rtl;
   dw_loc_descr_ref descr;
+  dw_loc_list_ref descr_list;
   var_loc_list *loc_list;
   struct var_loc_node *node;
   if (TREE_CODE (decl) == ERROR_MARK)
@@ -13539,18 +13836,18 @@ add_location_or_const_value_attribute (dw_die_ref die, tree decl,
       if (descr)
 	{
 	  descr = loc_by_reference (descr, decl);
-	  add_AT_location_description (die, attr, descr);
+	  add_AT_location_description (die, attr, single_element_loc_list (descr));
 	  return;
 	}
     }
 
   /* We couldn't get any rtl, so try directly generating the location
      description from the tree.  */
-  descr = loc_descriptor_from_tree (decl);
-  if (descr)
+  descr_list = loc_list_from_tree (decl, 2);
+  if (descr_list)
     {
       descr = loc_by_reference (descr, decl);
-      add_AT_location_description (die, attr, descr);
+      add_AT_location_description (die, attr, descr_list);
       return;
     }
   /* None of that worked, so it must not really have a location;
@@ -13967,7 +14264,7 @@ add_bound_info (dw_die_ref subrange_die, enum dwarf_attribute bound_attr, tree b
     case RESULT_DECL:
       {
 	dw_die_ref decl_die = lookup_decl_die (bound);
-	dw_loc_descr_ref loc;
+	dw_loc_list_ref loc;
 
 	/* ??? Can this happen, or should the variable have been bound
 	   first?  Probably it can, since I imagine that we try to create
@@ -13978,7 +14275,7 @@ add_bound_info (dw_die_ref subrange_die, enum dwarf_attribute bound_attr, tree b
 	  add_AT_die_ref (subrange_die, bound_attr, decl_die);
 	else
 	  {
-	    loc = loc_descriptor_from_tree_1 (bound, 0);
+	    loc = loc_list_from_tree (bound, 0);
 	    add_AT_location_description (subrange_die, bound_attr, loc);
 	  }
 	break;
@@ -13990,10 +14287,10 @@ add_bound_info (dw_die_ref subrange_die, enum dwarf_attribute bound_attr, tree b
 	   evaluate the value of the array bound.  */
 
 	dw_die_ref ctx, decl_die;
-	dw_loc_descr_ref loc;
+	dw_loc_list_ref list;
 
-	loc = loc_descriptor_from_tree (bound);
-	if (loc == NULL)
+	list = loc_list_from_tree (bound, 2);
+	if (list == NULL)
 	  break;
 
 	if (current_function_decl == 0)
@@ -14004,7 +14301,10 @@ add_bound_info (dw_die_ref subrange_die, enum dwarf_attribute bound_attr, tree b
 	decl_die = new_die (DW_TAG_variable, ctx, bound);
 	add_AT_flag (decl_die, DW_AT_artificial, 1);
 	add_type_attribute (decl_die, TREE_TYPE (bound), 1, 0, ctx);
-	add_AT_loc (decl_die, DW_AT_location, loc);
+	if (list->dw_loc_next)
+	  add_AT_loc_list (decl_die, DW_AT_location, list);
+	else
+	  add_AT_loc (decl_die, DW_AT_location, list->expr);
 
 	add_AT_die_ref (subrange_die, bound_attr, decl_die);
 	break;
@@ -14610,12 +14910,12 @@ gen_array_type_die (tree type, dw_die_ref context_die)
 	       && DECL_P (TYPE_MAX_VALUE (TYPE_DOMAIN (type))))
 	{
 	  tree szdecl = TYPE_MAX_VALUE (TYPE_DOMAIN (type));
-	  dw_loc_descr_ref loc = loc_descriptor_from_tree (szdecl);
+	  dw_loc_list_ref loc = loc_list_from_tree (szdecl, 2);
 
 	  size = int_size_in_bytes (TREE_TYPE (szdecl));
 	  if (loc && size > 0)
 	    {
-	      add_AT_loc (array_die, DW_AT_string_length, loc);
+	      add_AT_location_description (array_die, DW_AT_string_length, loc);
 	      if (size != DWARF2_ADDR_SIZE)
 		add_AT_unsigned (array_die, DW_AT_byte_size, size);
 	    }
@@ -14709,7 +15009,7 @@ descr_info_loc (tree val, tree base_decl)
     CASE_CONVERT:
       return descr_info_loc (TREE_OPERAND (val, 0), base_decl);
     case VAR_DECL:
-      return loc_descriptor_from_tree_1 (val, 0);
+      return loc_descriptor_from_tree (val, 0);
     case INTEGER_CST:
       if (host_integerp (val, 0))
 	return int_loc_descriptor (tree_low_cst (val, 0));
@@ -15015,7 +15315,7 @@ gen_formal_parameter_die (tree node, tree origin, dw_die_ref context_die)
 	{
 	  tree type = TREE_TYPE (node);
 	  add_name_and_src_coords_attributes (parm_die, node);
-	  if (DECL_BY_REFERENCE (node))
+	  if (decl_by_reference_p (node))
 	    add_type_attribute (parm_die, TREE_TYPE (type), 0, 0,
 				context_die);
 	  else
@@ -15467,7 +15767,7 @@ gen_subprogram_die (tree decl, dw_die_ref context_die)
 
       if (cfun->static_chain_decl)
 	add_AT_location_description (subr_die, DW_AT_static_link,
-		 loc_descriptor_from_tree (cfun->static_chain_decl));
+		 loc_list_from_tree (cfun->static_chain_decl, 2));
     }
 
   /* Generate child dies for template paramaters.  */
@@ -15637,7 +15937,7 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
     {
       tree field;
       dw_die_ref com_die;
-      dw_loc_descr_ref loc;
+      dw_loc_list_ref loc;
       die_node com_die_arg;
 
       var_die = lookup_decl_die (decl_or_origin);
@@ -15645,22 +15945,23 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
 	{
 	  if (get_AT (var_die, DW_AT_location) == NULL)
 	    {
-	      loc = loc_descriptor_from_tree (com_decl);
+	      loc = loc_list_from_tree (com_decl, off ? 1 : 2);
 	      if (loc)
 		{
 		  if (off)
 		    {
 		      /* Optimize the common case.  */
-		      if (loc->dw_loc_opc == DW_OP_addr
-			  && loc->dw_loc_next == NULL
-			  && GET_CODE (loc->dw_loc_oprnd1.v.val_addr)
+		      if (single_element_loc_list_p (loc)
+			  && loc->expr->dw_loc_opc == DW_OP_addr
+			  && loc->expr->dw_loc_next == NULL
+			  && GET_CODE (loc->expr->dw_loc_oprnd1.v.val_addr)
 			     == SYMBOL_REF)
-			loc->dw_loc_oprnd1.v.val_addr
-			  = plus_constant (loc->dw_loc_oprnd1.v.val_addr, off);
+			loc->expr->dw_loc_oprnd1.v.val_addr
+			  = plus_constant (loc->expr->dw_loc_oprnd1.v.val_addr, off);
 			else
-			  loc_descr_plus_const (&loc, off);
+			  loc_list_plus_const (loc, off);
 		    }
-		  add_AT_loc (var_die, DW_AT_location, loc);
+		  add_AT_location_description (var_die, DW_AT_location, loc);
 		  remove_AT (var_die, DW_AT_declaration);
 		}
 	    }
@@ -15676,7 +15977,7 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
       com_die_arg.decl_id = DECL_UID (com_decl);
       com_die_arg.die_parent = context_die;
       com_die = (dw_die_ref) htab_find (common_block_die_table, &com_die_arg);
-      loc = loc_descriptor_from_tree (com_decl);
+      loc = loc_list_from_tree (com_decl, 2);
       if (com_die == NULL)
 	{
 	  const char *cnam
@@ -15687,10 +15988,10 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
 	  add_name_and_src_coords_attributes (com_die, com_decl);
 	  if (loc)
 	    {
-	      add_AT_loc (com_die, DW_AT_location, loc);
+	      add_AT_location_description (com_die, DW_AT_location, loc);
 	      /* Avoid sharing the same loc descriptor between
 		 DW_TAG_common_block and DW_TAG_variable.  */
-	      loc = loc_descriptor_from_tree (com_decl);
+	      loc = loc_list_from_tree (com_decl, 2);
 	    }
           else if (DECL_EXTERNAL (decl))
 	    add_AT_flag (com_die, DW_AT_declaration, 1);
@@ -15701,8 +16002,8 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
 	}
       else if (get_AT (com_die, DW_AT_location) == NULL && loc)
 	{
-	  add_AT_loc (com_die, DW_AT_location, loc);
-	  loc = loc_descriptor_from_tree (com_decl);
+	  add_AT_location_description (com_die, DW_AT_location, loc);
+	  loc = loc_list_from_tree (com_decl, 2);
 	  remove_AT (com_die, DW_AT_declaration);
 	}
       var_die = new_die (DW_TAG_variable, com_die, decl);
@@ -15715,15 +16016,16 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
 	  if (off)
 	    {
 	      /* Optimize the common case.  */
-	      if (loc->dw_loc_opc == DW_OP_addr
-		  && loc->dw_loc_next == NULL
-		  && GET_CODE (loc->dw_loc_oprnd1.v.val_addr) == SYMBOL_REF)
-		loc->dw_loc_oprnd1.v.val_addr
-		  = plus_constant (loc->dw_loc_oprnd1.v.val_addr, off);
+	      if (single_element_loc_list_p (loc)
+		  && loc->expr->dw_loc_opc == DW_OP_addr
+		  && loc->expr->dw_loc_next == NULL
+		  && GET_CODE (loc->expr->dw_loc_oprnd1.v.val_addr) == SYMBOL_REF)
+		loc->expr->dw_loc_oprnd1.v.val_addr
+		  = plus_constant (loc->expr->dw_loc_oprnd1.v.val_addr, off);
 	      else
-		loc_descr_plus_const (&loc, off);
+		loc_list_plus_const (loc, off);
 	    }
-	  add_AT_loc (var_die, DW_AT_location, loc);
+	  add_AT_location_description (var_die, DW_AT_location, loc);
 	}
       else if (DECL_EXTERNAL (decl))
 	add_AT_flag (var_die, DW_AT_declaration, 1);
@@ -15786,10 +16088,7 @@ gen_variable_die (tree decl, tree origin, dw_die_ref context_die)
       tree type = TREE_TYPE (decl);
 
       add_name_and_src_coords_attributes (var_die, decl);
-      if ((TREE_CODE (decl) == PARM_DECL
-	   || TREE_CODE (decl) == RESULT_DECL
-	   || TREE_CODE (decl) == VAR_DECL)
-	  && DECL_BY_REFERENCE (decl))
+      if (decl_by_reference_p (decl))
 	add_type_attribute (var_die, TREE_TYPE (type), 0, 0, context_die);
       else
 	add_type_attribute (var_die, type, TREE_READONLY (decl),
@@ -17066,9 +17365,7 @@ gen_decl_die (tree decl, tree origin, dw_die_ref context_die)
 
       /* Output any DIEs that are needed to specify the type of this data
 	 object.  */
-      if ((TREE_CODE (decl_or_origin) == RESULT_DECL
-	   || TREE_CODE (decl_or_origin) == VAR_DECL)
-          && DECL_BY_REFERENCE (decl_or_origin))
+      if (decl_by_reference_p (decl_or_origin))
 	gen_type_die (TREE_TYPE (TREE_TYPE (decl_or_origin)), context_die);
       else
 	gen_type_die (TREE_TYPE (decl_or_origin), context_die);

gcc/final.c

@@ -4304,7 +4304,7 @@ struct rtl_opt_pass pass_final =
 {
  {
   RTL_PASS,
-  NULL,                                 /* name */
+  "final",                              /* name */
   NULL,                                 /* gate */
   rest_of_handle_final,                 /* execute */
   NULL,                                 /* sub */