gdb/

	Fix PR 10640.
	* dwarf2-frame.c (no_dwarf_call): New function.
	(execute_stack_op): Set CTX->DWARF_CALL.
	* dwarf2expr.c (execute_stack_op) <DW_OP_call2, DW_OP_call4>: New.
	* dwarf2expr.h (struct dwarf_expr_context) <dwarf_call>: New.
	(struct dwarf_expr_context) <get_subr>: Remove the #if0-ed field.
	* dwarf2loc.c (per_cu_dwarf_call, dwarf_expr_dwarf_call): New functions.
	(dwarf2_evaluate_loc_desc): Initialize CTX->DWARF_CALL.
	(needs_frame_dwarf_call): New function.
	(dwarf2_loc_desc_needs_frame): Initialize CTX->DWARF_CALL.
	* dwarf2read.c (follow_die_offset): Based on former follow_die_ref.
	Update the comment.  Move variables die, offset and error call to ...
	(follow_die_ref): ... a new function.
	(dwarf2_fetch_die_location_block): New function.
	* dwarf2loc.h (dwarf2_fetch_die_location_block): New prototype.

gdb/testsuite/
	Test PR 10640.
	* gdb.dwarf2/dw2-op-call.exp, gdb.dwarf2/dw2-op-call.S: New.

10 files changed, 315 insertions, 22 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 7113eb4..955b848 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,23 @@
 2010-06-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
 
+	Fix PR 10640.
+	* dwarf2-frame.c (no_dwarf_call): New function.
+	(execute_stack_op): Set CTX->DWARF_CALL.
+	* dwarf2expr.c (execute_stack_op) <DW_OP_call2, DW_OP_call4>: New.
+	* dwarf2expr.h (struct dwarf_expr_context) <dwarf_call>: New.
+	(struct dwarf_expr_context) <get_subr>: Remove the #if0-ed field.
+	* dwarf2loc.c (per_cu_dwarf_call, dwarf_expr_dwarf_call): New functions.
+	(dwarf2_evaluate_loc_desc): Initialize CTX->DWARF_CALL.
+	(needs_frame_dwarf_call): New function.
+	(dwarf2_loc_desc_needs_frame): Initialize CTX->DWARF_CALL.
+	* dwarf2read.c (follow_die_offset): Based on former follow_die_ref.
+	Update the comment.  Move variables die, offset and error call to ...
+	(follow_die_ref): ... a new function.
+	(dwarf2_fetch_die_location_block): New function.
+	* dwarf2loc.h (dwarf2_fetch_die_location_block): New prototype.
+
+2010-06-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
 	* dwarf2loc.c (struct dwarf_expr_baton) Replace objfile by per_cu.
 	(dwarf_expr_tls_address): Use per_cu instead of objfile.
 	(dwarf2_evaluate_loc_desc): Drop initialization of BATON.OBJFILE.
diff --git a/gdb/dwarf2-frame.c b/gdb/dwarf2-frame.c
index 2ac95b0..68793cd 100644
--- a/gdb/dwarf2-frame.c
+++ b/gdb/dwarf2-frame.c
@@ -328,6 +328,15 @@ no_get_tls_address (void *baton, CORE_ADDR offset)
 		  _("Support for DW_OP_GNU_push_tls_address is unimplemented"));
 }
 
+/* Helper function for execute_stack_op.  */
+
+static void
+no_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+  internal_error (__FILE__, __LINE__,
+		  _("Support for DW_OP_call* is invalid in CFI"));
+}
+
 /* Execute the required actions for both the DW_CFA_restore and
 DW_CFA_restore_extended instructions.  */
 static void
@@ -378,6 +387,7 @@ execute_stack_op (const gdb_byte *exp, ULONGEST len, int addr_size,
   ctx->get_frame_base = no_get_frame_base;
   ctx->get_frame_cfa = no_get_frame_cfa;
   ctx->get_tls_address = no_get_tls_address;
+  ctx->dwarf_call = no_dwarf_call;
 
   dwarf_expr_push (ctx, initial, initial_in_stack_memory);
   dwarf_expr_eval (ctx, exp, len);
diff --git a/gdb/dwarf2expr.c b/gdb/dwarf2expr.c
index c145cf4..4e5a0fc 100644
--- a/gdb/dwarf2expr.c
+++ b/gdb/dwarf2expr.c
@@ -911,6 +911,18 @@ execute_stack_op (struct dwarf_expr_context *ctx,
 	  ctx->initialized = 0;
 	  goto no_push;
 
+	case DW_OP_call2:
+	  result = extract_unsigned_integer (op_ptr, 2, byte_order);
+	  op_ptr += 2;
+	  ctx->dwarf_call (ctx, result);
+	  goto no_push;
+
+	case DW_OP_call4:
+	  result = extract_unsigned_integer (op_ptr, 4, byte_order);
+	  op_ptr += 4;
+	  ctx->dwarf_call (ctx, result);
+	  goto no_push;
+
 	default:
 	  error (_("Unhandled dwarf expression opcode 0x%x"), op);
 	}
diff --git a/gdb/dwarf2expr.h b/gdb/dwarf2expr.h
index 8ebbf87..29f81a5 100644
--- a/gdb/dwarf2expr.h
+++ b/gdb/dwarf2expr.h
@@ -97,15 +97,14 @@ struct dwarf_expr_context
      DW_OP_GNU_push_tls_address.  */
   CORE_ADDR (*get_tls_address) (void *baton, CORE_ADDR offset);
 
+  /* Execute DW_AT_location expression for the DWARF expression subroutine in
+     the DIE at DIE_OFFSET in the CU from CTX.  Do not touch STACK while it
+     being passed to and returned from the called DWARF subroutine.  */
+  void (*dwarf_call) (struct dwarf_expr_context *ctx, size_t die_offset);
+
 #if 0
   /* Not yet implemented.  */
 
-  /* Return the location expression for the dwarf expression
-     subroutine in the die at OFFSET in the current compilation unit.
-     The result must be live until the current expression evaluation
-     is complete.  */
-  unsigned char *(*get_subr) (void *baton, off_t offset, size_t *length);
-
   /* Return the `object address' for DW_OP_push_object_address.  */
   CORE_ADDR (*get_object_address) (void *baton);
 #endif
diff --git a/gdb/dwarf2loc.c b/gdb/dwarf2loc.c
index 9864c46..8a9a346 100644
--- a/gdb/dwarf2loc.c
+++ b/gdb/dwarf2loc.c
@@ -232,6 +232,33 @@ dwarf_expr_tls_address (void *baton, CORE_ADDR offset)
   return target_translate_tls_address (objfile, offset);
 }
 
+/* Call DWARF subroutine from DW_AT_location of DIE at DIE_OFFSET in current CU
+   (as is PER_CU).  State of the CTX is not affected by the call and return.  */
+
+static void
+per_cu_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset,
+		   struct dwarf2_per_cu_data *per_cu)
+{
+  struct dwarf2_locexpr_baton block;
+
+  block = dwarf2_fetch_die_location_block (die_offset, per_cu);
+
+  /* DW_OP_call_ref is currently not supported.  */
+  gdb_assert (block.per_cu == per_cu);
+
+  dwarf_expr_eval (ctx, block.data, block.size);
+}
+
+/* Helper interface of per_cu_dwarf_call for dwarf2_evaluate_loc_desc.  */
+
+static void
+dwarf_expr_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+  struct dwarf_expr_baton *debaton = ctx->baton;
+
+  return per_cu_dwarf_call (ctx, die_offset, debaton->per_cu);
+}
+
 struct piece_closure
 {
   /* Reference count.  */
@@ -815,6 +842,7 @@ dwarf2_evaluate_loc_desc (struct type *type, struct frame_info *frame,
   ctx->get_frame_base = dwarf_expr_frame_base;
   ctx->get_frame_cfa = dwarf_expr_frame_cfa;
   ctx->get_tls_address = dwarf_expr_tls_address;
+  ctx->dwarf_call = dwarf_expr_dwarf_call;
 
   dwarf_expr_eval (ctx, data, size);
   if (ctx->num_pieces > 0)
@@ -962,6 +990,16 @@ needs_frame_tls_address (void *baton, CORE_ADDR offset)
   return 1;
 }
 
+/* Helper interface of per_cu_dwarf_call for dwarf2_loc_desc_needs_frame.  */
+
+static void
+needs_frame_dwarf_call (struct dwarf_expr_context *ctx, size_t die_offset)
+{
+  struct needs_frame_baton *nf_baton = ctx->baton;
+
+  return per_cu_dwarf_call (ctx, die_offset, nf_baton->per_cu);
+}
+
 /* Return non-zero iff the location expression at DATA (length SIZE)
    requires a frame to evaluate.  */
 
@@ -988,6 +1026,7 @@ dwarf2_loc_desc_needs_frame (const gdb_byte *data, unsigned short size,
   ctx->get_frame_base = needs_frame_frame_base;
   ctx->get_frame_cfa = needs_frame_frame_cfa;
   ctx->get_tls_address = needs_frame_tls_address;
+  ctx->dwarf_call = needs_frame_dwarf_call;
 
   dwarf_expr_eval (ctx, data, size);
 
diff --git a/gdb/dwarf2loc.h b/gdb/dwarf2loc.h
index 4938241..3ff595e 100644
--- a/gdb/dwarf2loc.h
+++ b/gdb/dwarf2loc.h
@@ -37,6 +37,9 @@ CORE_ADDR dwarf2_per_cu_addr_size (struct dwarf2_per_cu_data *cu);
 /* Return the offset size given in the compilation unit header for CU.  */
 int dwarf2_per_cu_offset_size (struct dwarf2_per_cu_data *cu);
 
+struct dwarf2_locexpr_baton dwarf2_fetch_die_location_block
+  (unsigned int offset, struct dwarf2_per_cu_data *per_cu);
+
 /* The symbol location baton types used by the DWARF-2 reader (i.e.
    SYMBOL_LOCATION_BATON for a LOC_COMPUTED symbol).  "struct
    dwarf2_locexpr_baton" is for a symbol with a single location
diff --git a/gdb/dwarf2read.c b/gdb/dwarf2read.c
index 6a6f1cb..05fbd09 100644
--- a/gdb/dwarf2read.c
+++ b/gdb/dwarf2read.c
@@ -10736,30 +10736,25 @@ follow_die_ref_or_sig (struct die_info *src_die, struct attribute *attr,
   return die;
 }
 
-/* Follow reference attribute ATTR of SRC_DIE.
-   On entry *REF_CU is the CU of SRC_DIE.
+/* Follow reference OFFSET.
+   On entry *REF_CU is the CU of source DIE referencing OFFSET.
    On exit *REF_CU is the CU of the result.  */
 
 static struct die_info *
-follow_die_ref (struct die_info *src_die, struct attribute *attr,
-		struct dwarf2_cu **ref_cu)
+follow_die_offset (unsigned int offset, struct dwarf2_cu **ref_cu)
 {
-  struct die_info *die;
-  unsigned int offset;
   struct die_info temp_die;
   struct dwarf2_cu *target_cu, *cu = *ref_cu;
 
   gdb_assert (cu->per_cu != NULL);
 
-  offset = dwarf2_get_ref_die_offset (attr);
-
   if (cu->per_cu->from_debug_types)
     {
       /* .debug_types CUs cannot reference anything outside their CU.
 	 If they need to, they have to reference a signatured type via
 	 DW_FORM_sig8.  */
       if (! offset_in_cu_p (&cu->header, offset))
-	goto not_found;
+	return NULL;
       target_cu = cu;
     }
   else if (! offset_in_cu_p (&cu->header, offset))
@@ -10779,15 +10774,67 @@ follow_die_ref (struct die_info *src_die, struct attribute *attr,
 
   *ref_cu = target_cu;
   temp_die.offset = offset;
-  die = htab_find_with_hash (target_cu->die_hash, &temp_die, offset);
-  if (die)
-    return die;
+  return htab_find_with_hash (target_cu->die_hash, &temp_die, offset);
+}
 
- not_found:
+/* Follow reference attribute ATTR of SRC_DIE.
+   On entry *REF_CU is the CU of SRC_DIE.
+   On exit *REF_CU is the CU of the result.  */
 
-  error (_("Dwarf Error: Cannot find DIE at 0x%x referenced from DIE "
-	 "at 0x%x [in module %s]"),
-	 offset, src_die->offset, cu->objfile->name);
+static struct die_info *
+follow_die_ref (struct die_info *src_die, struct attribute *attr,
+		struct dwarf2_cu **ref_cu)
+{
+  unsigned int offset = dwarf2_get_ref_die_offset (attr);
+  struct dwarf2_cu *cu = *ref_cu;
+  struct die_info *die;
+
+  die = follow_die_offset (offset, ref_cu);
+  if (!die)
+    error (_("Dwarf Error: Cannot find DIE at 0x%x referenced from DIE "
+	   "at 0x%x [in module %s]"),
+	   offset, src_die->offset, cu->objfile->name);
+
+  return die;
+}
+
+/* Return DWARF block and its CU referenced by OFFSET at PER_CU.  Returned
+   value is intended for DW_OP_call*.  */
+
+struct dwarf2_locexpr_baton
+dwarf2_fetch_die_location_block (unsigned int offset,
+				 struct dwarf2_per_cu_data *per_cu)
+{
+  struct dwarf2_cu *cu = per_cu->cu;
+  struct die_info *die;
+  struct attribute *attr;
+  struct dwarf2_locexpr_baton retval;
+
+  die = follow_die_offset (offset, &cu);
+  if (!die)
+    error (_("Dwarf Error: Cannot find DIE at 0x%x referenced in module %s"),
+	   offset, per_cu->cu->objfile->name);
+
+  attr = dwarf2_attr (die, DW_AT_location, cu);
+  if (!attr)
+    {
+      /* DWARF: "If there is no such attribute, then there is no effect.".  */
+
+      retval.data = NULL;
+      retval.size = 0;
+    }
+  else
+    {
+      if (!attr_form_is_block (attr))
+	error (_("Dwarf Error: DIE at 0x%x referenced in module %s "
+		 "is neither DW_FORM_block* nor DW_FORM_exprloc"),
+	       offset, per_cu->cu->objfile->name);
+
+      retval.data = DW_BLOCK (attr)->data;
+      retval.size = DW_BLOCK (attr)->size;
+    }
+  retval.per_cu = cu->per_cu;
+  return retval;
 }
 
 /* Follow the signature attribute ATTR in SRC_DIE.
diff --git a/gdb/testsuite/ChangeLog b/gdb/testsuite/ChangeLog
index 291175b..5ec9006 100644
--- a/gdb/testsuite/ChangeLog
+++ b/gdb/testsuite/ChangeLog
@@ -1,3 +1,8 @@
+2010-06-07  Jan Kratochvil  <jan.kratochvil@redhat.com>
+
+	Test PR 10640.
+	* gdb.dwarf2/dw2-op-call.exp, gdb.dwarf2/dw2-op-call.S: New.
+
 2010-06-07  Sami Wagiaalla  <swagiaal@redhat.com>
 
 	* gdb.cp/koenig.exp: Test for ADL operators.
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-op-call.S b/gdb/testsuite/gdb.dwarf2/dw2-op-call.S
new file mode 100644
index 0000000..068e224
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-op-call.S
@@ -0,0 +1,119 @@
+/* This testcase is part of GDB, the GNU debugger.
+
+   Copyright 2009 Free Software Foundation, Inc.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Test DW_OP_call2 and DW_OP_call4, PR gdb/10640.  */
+
+	.section .data
+array1:	.2byte	1
+array2:	.2byte	2
+array3:	.2byte	3
+
+	.section .debug_info
+.Lcu1_begin:
+	/* CU header */
+	.4byte	.Lcu1_end - .Lcu1_start		/* Length of Compilation Unit */
+.Lcu1_start:
+	.2byte	2				/* DWARF Version */
+	.4byte	.Labbrev1_begin			/* Offset into abbrev section */
+	.byte	4				/* Pointer size */
+
+	/* CU die */
+	.uleb128 1				/* Abbrev: DW_TAG_compile_unit */
+	.ascii	"file1.txt\0"			/* DW_AT_name */
+	.ascii	"GNU C 3.3.3\0"			/* DW_AT_producer */
+	.byte	2				/* DW_LANG_C (C) */
+
+.L2byte_type:
+	.uleb128	2			/* Abbrev: DW_TAG_base_type */
+	.ascii		"2byte\0"		/* DW_AT_name */
+	.byte		2			/* DW_AT_byte_size */
+	.byte		7			/* DW_AT_encoding: DW_ATE_unsigned */
+
+.Larray1:
+	.uleb128	3			/* Abbrev: DW_TAG_variable */
+	.ascii		"array1\0"		/* DW_AT_name */
+	.4byte		.L2byte_type-.Lcu1_begin	/* DW_AT_type */
+	.byte		2f - 1f			/* DW_AT_location */
+1:	.byte		3			/*   DW_OP_addr */
+	.4byte		array			/*     <addr> */
+2:
+
+	.uleb128	3			/* Abbrev: DW_TAG_variable */
+	.ascii		"array2\0"		/* DW_AT_name */
+	.4byte		.L2byte_type-.Lcu1_begin	/* DW_AT_type */
+	.byte		2f - 1f			/* DW_AT_location */
+1:	.byte		0x98			/*   DW_OP_call2 */
+	.2byte		.Larray1-.Lcu1_begin	/*     <current CU offset> */
+	.byte		0x23			/*   DW_OP_plus_uconst */
+	.uleb128	array2-array1		/*     <uconst> */
+2:
+
+	.uleb128	3			/* Abbrev: DW_TAG_variable */
+	.ascii		"array3\0"		/* DW_AT_name */
+	.4byte		.L2byte_type-.Lcu1_begin	/* DW_AT_type */
+	.byte		2f - 1f			/* DW_AT_location */
+1:	.byte		0x99			/*   DW_OP_call4 */
+	.4byte		.Larray1-.Lcu1_begin	/*     <current CU offset> */
+	.byte		0x23			/*   DW_OP_plus_uconst */
+	.uleb128	array3-array1		/*     <uconst> */
+2:
+
+	.byte		0			/* End of children of CU */
+
+.Lcu1_end:
+
+/* Abbrev table */
+	.section .debug_abbrev
+.Labbrev1_begin:
+	.uleb128	1			/* Abbrev code */
+	.uleb128	0x11			/* DW_TAG_compile_unit */
+	.byte		1			/* has_children */
+	.uleb128	0x3			/* DW_AT_name */
+	.uleb128	0x8			/* DW_FORM_string */
+	.uleb128	0x25			/* DW_AT_producer */
+	.uleb128	0x8			/* DW_FORM_string */
+	.uleb128	0x13			/* DW_AT_language */
+	.uleb128	0xb			/* DW_FORM_data1 */
+	.byte		0x0			/* Terminator */
+	.byte		0x0			/* Terminator */
+
+	.uleb128	2			/* Abbrev code */
+	.uleb128	0x24			/* DW_TAG_base_type */
+	.byte		0			/* has_children */
+	.uleb128	0x3			/* DW_AT_name */
+	.uleb128	0x8			/* DW_FORM_string */
+	.uleb128	0xb			/* DW_AT_byte_size */
+	.uleb128	0xb			/* DW_FORM_data1 */
+	.uleb128	0x3e			/* DW_AT_encoding */
+	.uleb128	0xb			/* DW_FORM_data1 */
+	.byte		0x0			/* Terminator */
+	.byte		0x0			/* Terminator */
+
+	.uleb128	3			/* Abbrev code */
+	.uleb128	0x34			/* DW_TAG_variable */
+	.byte		0			/* has_children */
+	.uleb128	0x3			/* DW_AT_name */
+	.uleb128	0x8			/* DW_FORM_string */
+	.uleb128	0x49			/* DW_AT_type */
+	.uleb128	0x13			/* DW_FORM_ref4 */
+	.uleb128	0x2			/* DW_AT_location */
+	.uleb128	0xa			/* DW_FORM_block1 */
+	.byte		0x0			/* Terminator */
+	.byte		0x0			/* Terminator */
+
+	.byte		0x0			/* Terminator */
+	.byte		0x0			/* Terminator */
diff --git a/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp b/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp
new file mode 100644
index 0000000..5b5fefd
--- /dev/null
+++ b/gdb/testsuite/gdb.dwarf2/dw2-op-call.exp
@@ -0,0 +1,41 @@
+# Copyright 2009 Free Software Foundation, Inc.
+
+# This program is free software; you can redistribute it and/or modify
+# it under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# This program is distributed in the hope that it will be useful,
+# but WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with this program.  If not, see <http://www.gnu.org/licenses/>.
+
+# Test DW_OP_call2 and DW_OP_call4, PR gdb/10640.
+
+# This test can only be run on targets which support DWARF-2 and use gas.
+# For now pick a sampling of likely targets.
+if {![istarget *-*-linux*]
+    && ![istarget *-*-gnu*]
+    && ![istarget *-*-elf*]
+    && ![istarget *-*-openbsd*]
+    && ![istarget arm-*-eabi*]
+    && ![istarget powerpc-*-eabi*]} {
+    return 0  
+}
+
+set testfile "dw2-op-call"
+set srcfile ${testfile}.S
+set executable ${testfile}.x
+
+if  { [gdb_compile "${srcdir}/${subdir}/${srcfile}" "${objdir}/${subdir}/${executable}" object {nodebug}] != "" } {
+    return -1
+}
+
+clean_restart $executable
+
+gdb_test "p array1" " = 1"
+gdb_test "p array2" " = 2" "array2 using DW_OP_call2"
+gdb_test "p array3" " = 3" "array3 using DW_OP_call4"