dwarf2out.c (new_loc_descr_op_bit_piece): Add offset argument.

	* dwarf2out.c (new_loc_descr_op_bit_piece): Add offset
	argument.  Don't use DW_OP_piece if offset is non-zero,
	put offset into second DW_OP_bit_piece argument.
	(dw_sra_loc_expr): Adjust callers.  For memory expressions
	compute offset.

From-SVN: r159623

diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index cde189eed40f8e76e607a28e4e19d453917d9540..ee86787de69abe2b1af4b13b12cdd71337a9b499 100644 (file)
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,11 @@
+2010-05-20  Jakub Jelinek  <jakub@redhat.com>
+
+       * dwarf2out.c (new_loc_descr_op_bit_piece): Add offset
+       argument.  Don't use DW_OP_piece if offset is non-zero,
+       put offset into second DW_OP_bit_piece argument.
+       (dw_sra_loc_expr): Adjust callers.  For memory expressions
+       compute offset.
+
 2010-05-20  Hans-Peter Nilsson  <hp@axis.com>
 
        PR target/44202

diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
index e68065b2c1e9c8350227406feb1721ee94bc2d52..1f6e9021d1678923c18a4eca4dd32b1c1f18f1b0 100644 (file)
--- a/gcc/dwarf2out.c
+++ b/gcc/dwarf2out.c
@@ -14364,12 +14364,12 @@ dw_loc_list_1 (tree loc, rtx varloc, int want_address,
    if it is not possible.  */
 
 static dw_loc_descr_ref
-new_loc_descr_op_bit_piece (HOST_WIDE_INT bitsize)
+new_loc_descr_op_bit_piece (HOST_WIDE_INT bitsize, HOST_WIDE_INT offset)
 {
-  if ((bitsize % BITS_PER_UNIT) == 0)
+  if ((bitsize % BITS_PER_UNIT) == 0 && offset == 0)
     return new_loc_descr (DW_OP_piece, bitsize / BITS_PER_UNIT, 0);
   else if (dwarf_version >= 3 || !dwarf_strict)
-    return new_loc_descr (DW_OP_bit_piece, bitsize, 0);
+    return new_loc_descr (DW_OP_bit_piece, bitsize, offset);
   else
     return NULL;
 }
@@ -14448,7 +14448,7 @@ dw_sra_loc_expr (tree decl, rtx loc)
          if (padsize > decl_size)
            return NULL;
          decl_size -= padsize;
-         *descr_tail = new_loc_descr_op_bit_piece (padsize);
+         *descr_tail = new_loc_descr_op_bit_piece (padsize, 0);
          if (*descr_tail == NULL)
            return NULL;
          descr_tail = &(*descr_tail)->dw_loc_next;
@@ -14461,7 +14461,47 @@ dw_sra_loc_expr (tree decl, rtx loc)
       decl_size -= bitsize;
       if (last == NULL)
        {
-         *descr_tail = new_loc_descr_op_bit_piece (bitsize);
+         HOST_WIDE_INT offset = 0;
+         if (GET_CODE (varloc) == VAR_LOCATION
+             && GET_CODE (PAT_VAR_LOCATION_LOC (varloc)) != PARALLEL)
+           {
+             varloc = PAT_VAR_LOCATION_LOC (varloc);
+             if (GET_CODE (varloc) == EXPR_LIST)
+               varloc = XEXP (varloc, 0);
+           }
+         do 
+           {
+             if (GET_CODE (varloc) == CONST
+                 || GET_CODE (varloc) == SIGN_EXTEND
+                 || GET_CODE (varloc) == ZERO_EXTEND)
+               varloc = XEXP (varloc, 0);
+             else if (GET_CODE (varloc) == SUBREG)
+               varloc = SUBREG_REG (varloc);
+             else
+               break;
+           }
+         while (1);
+         /* DW_OP_bit_size offset should be zero for register
+            or implicit location descriptions and empty location
+            descriptions, but for memory addresses needs big endian
+            adjustment.  */
+         if (MEM_P (varloc))
+           {
+             unsigned HOST_WIDE_INT memsize
+               = INTVAL (MEM_SIZE (varloc)) * BITS_PER_UNIT;
+             if (memsize != bitsize)
+               {
+                 if (BYTES_BIG_ENDIAN != WORDS_BIG_ENDIAN
+                     && (memsize > BITS_PER_WORD || bitsize > BITS_PER_WORD))
+                   return NULL;
+                 if (memsize < bitsize)
+                   return NULL;
+                 if (BITS_BIG_ENDIAN)
+                   offset = memsize - bitsize;
+               }
+           }
+
+         *descr_tail = new_loc_descr_op_bit_piece (bitsize, offset);
          if (*descr_tail == NULL)
            return NULL;
          descr_tail = &(*descr_tail)->dw_loc_next;
@@ -14472,7 +14512,7 @@ dw_sra_loc_expr (tree decl, rtx loc)
      the decl.  */
   if (descr != NULL && decl_size != 0)
     {
-      *descr_tail = new_loc_descr_op_bit_piece (decl_size);
+      *descr_tail = new_loc_descr_op_bit_piece (decl_size, 0);
       if (*descr_tail == NULL)
        return NULL;
     }