[PATCH] Fix up typed DWARF stack support for POINTERS_EXTEND_UNSIGNED targets (PR debug/48853)

[Jakub Jelinek]

Hi!

My typed DWARF stack changes apparently broke ia64-hpux and H.J.'s out of
tree x32 target.  There are several issues:
1) for SUBREG mem_loc_descriptor's 3rd argument was wrong, found by code
   inspection
2) CONST/SYMBOL_REF/LABEL_REF when in MEM addresses on POINTERS_EXTEND_UNSIGNED
   targets are often Pmode, which is unfortunately larger than DWARF2_ADDR_SIZE
   and my conditional would just return NULL in that case instead of
   emitting DW_OP_addr.
3) and, when mem_loc_descriptor is called from unwind code, Pmodes larger
   than DWARF2_ADDR_SIZE would result in the new DW_OP_GNU_*_type etc. ops
   which are not allowed in .eh_frame/.debug_frame
The following patch ought to fix that, bootstrapped/regtested on
x86_64-linux and i686-linux and Steve tested it on ia64-hpux and H.J. on his
port.  Ok for trunk?

2011-05-05  Jakub Jelinek  <jakub@redhat.com>

	PR debug/48853
	* dwarf2out.c (mem_loc_descriptor) <case SUBREG>: Pass mem_mode
	instead of mode as 3rd argument to recursive call.
	(mem_loc_descriptor) <case REG>: If POINTERS_EXTEND_UNSIGNED, don't
	emit DW_OP_GNU_regval_type if mode is Pmode and mem_mode is not
	VOIDmode.
	(mem_loc_descriptor) <case SYMBOL_REF>: If POINTERS_EXTEND_UNSIGNED,
	don't give up if mode is Pmode and mem_mode is not VOIDmode.
	(mem_loc_descriptor) <case CONST_INT>: If POINTERS_EXTEND_UNSIGNED,
	use int_loc_descriptor if mode is Pmode and mem_mode is not VOIDmode.

--- gcc/dwarf2out.c.jj	2011-05-04 10:14:08.000000000 +0200
+++ gcc/dwarf2out.c	2011-05-04 19:08:22.000000000 +0200
@@ -13883,7 +13883,7 @@ mem_loc_descriptor (rtx rtl, enum machin
 
 	  mem_loc_result = mem_loc_descriptor (SUBREG_REG (rtl),
 					       GET_MODE (SUBREG_REG (rtl)),
-					       mode, initialized);
+					       mem_mode, initialized);
 	  if (mem_loc_result == NULL)
 	    break;
 	  type_die = base_type_for_mode (mode, 0);
@@ -13906,7 +13906,13 @@ mem_loc_descriptor (rtx rtl, enum machin
 
     case REG:
       if (GET_MODE_CLASS (mode) != MODE_INT
-	  || GET_MODE_SIZE (mode) > DWARF2_ADDR_SIZE)
+	  || (GET_MODE_SIZE (mode) > DWARF2_ADDR_SIZE
+#ifdef POINTERS_EXTEND_UNSIGNED
+	      && (mode != Pmode
+		  || GET_MODE_SIZE (ptr_mode) != DWARF2_ADDR_SIZE
+		  || mem_mode == VOIDmode)
+#endif
+	      ))
 	{
 	  dw_die_ref type_die;
 
@@ -14049,9 +14055,18 @@ mem_loc_descriptor (rtx rtl, enum machin
 	 pool.  */
     case CONST:
     case SYMBOL_REF:
+      if (GET_MODE_CLASS (mode) != MODE_INT)
+	break;
+#ifndef POINTERS_EXTEND_UNSIGNED
+      if (GET_MODE_SIZE (mode) > DWARF2_ADDR_SIZE)
+	break;
+#else
       if (GET_MODE_SIZE (mode) > DWARF2_ADDR_SIZE
-	  || GET_MODE_CLASS (mode) != MODE_INT)
+	  && (mode != Pmode
+	      || GET_MODE_SIZE (ptr_mode) != DWARF2_ADDR_SIZE
+	      || mem_mode == VOIDmode))
 	break;
+#endif
       if (GET_CODE (rtl) == SYMBOL_REF
 	  && SYMBOL_REF_TLS_MODEL (rtl) != TLS_MODEL_NONE)
 	{
@@ -14288,7 +14303,14 @@ mem_loc_descriptor (rtx rtl, enum machin
       break;
 
     case CONST_INT:
-      if (GET_MODE_SIZE (mode) <= DWARF2_ADDR_SIZE)
+      if (GET_MODE_SIZE (mode) <= DWARF2_ADDR_SIZE
+#ifdef POINTERS_EXTEND_UNSIGNED
+	  || (mode == Pmode
+	      && GET_MODE_SIZE (ptr_mode) == DWARF2_ADDR_SIZE
+	      && mem_mode != VOIDmode
+	      && trunc_int_for_mode (INTVAL (rtl), ptr_mode) == INTVAL (rtl))
+#endif
+	  )
 	{
 	  mem_loc_result = int_loc_descriptor (INTVAL (rtl));
 	  break;

	Jakub