2011-03-18 Phil Muldoon <pmuldoon@redhat.com>

[deliverable/binutils-gdb.git] / gdb / dwarf2expr.c

diff --git a/gdb/dwarf2expr.c b/gdb/dwarf2expr.c
index b9ae108c5ffecd3a943711d5a52d1de66363e433..8d1810e0a9598e1ccd855824fa9adb07165b6ba1 100644 (file)
--- a/gdb/dwarf2expr.c
+++ b/gdb/dwarf2expr.c
@@ -1,6 +1,6 @@
 /* DWARF 2 Expression Evaluator.
 
-   Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010
+   Copyright (C) 2001, 2002, 2003, 2005, 2007, 2008, 2009, 2010, 2011
    Free Software Foundation, Inc.
 
    Contributed by Daniel Berlin (dan@dberlin.org)
@@ -129,7 +129,8 @@ ULONGEST
 dwarf_expr_fetch (struct dwarf_expr_context *ctx, int n)
 {
   if (ctx->stack_len <= n)
-     error (_("Asked for position %d of stack, stack only has %d elements on it."),
+     error (_("Asked for position %d of stack, "
+             "stack only has %d elements on it."),
            n, ctx->stack_len);
   return ctx->stack[ctx->stack_len - (1 + n)].value;
 
@@ -183,7 +184,8 @@ int
 dwarf_expr_fetch_in_stack_memory (struct dwarf_expr_context *ctx, int n)
 {
   if (ctx->stack_len <= n)
-     error (_("Asked for position %d of stack, stack only has %d elements on it."),
+     error (_("Asked for position %d of stack, "
+             "stack only has %d elements on it."),
            n, ctx->stack_len);
   return ctx->stack[ctx->stack_len - (1 + n)].in_stack_memory;
 
@@ -233,6 +235,11 @@ add_piece (struct dwarf_expr_context *ctx, ULONGEST size, ULONGEST offset)
       p->v.mem.addr = dwarf_expr_fetch_address (ctx, 0);
       p->v.mem.in_stack_memory = dwarf_expr_fetch_in_stack_memory (ctx, 0);
     }
+  else if (p->location == DWARF_VALUE_IMPLICIT_POINTER)
+    {
+      p->v.ptr.die = ctx->len;
+      p->v.ptr.offset = (LONGEST) dwarf_expr_fetch (ctx, 0);
+    }
   else
     {
       p->v.value = dwarf_expr_fetch (ctx, 0);
@@ -527,6 +534,26 @@ execute_stack_op (struct dwarf_expr_context *ctx,
          dwarf_expr_require_composition (op_ptr, op_end, "DW_OP_stack_value");
          goto no_push;
 
+       case DW_OP_GNU_implicit_pointer:
+         {
+           ULONGEST die;
+           LONGEST len;
+
+           /* The referred-to DIE.  */
+           ctx->len = extract_unsigned_integer (op_ptr, ctx->addr_size,
+                                                byte_order);
+           op_ptr += ctx->addr_size;
+
+           /* The byte offset into the data.  */
+           op_ptr = read_sleb128 (op_ptr, op_end, &len);
+           result = (ULONGEST) len;
+
+           ctx->location = DWARF_VALUE_IMPLICIT_POINTER;
+           dwarf_expr_require_composition (op_ptr, op_end,
+                                           "DW_OP_GNU_implicit_pointer");
+         }
+         break;
+
        case DW_OP_breg0:
        case DW_OP_breg1:
        case DW_OP_breg2:
@@ -595,7 +622,8 @@ execute_stack_op (struct dwarf_expr_context *ctx,
            else if (ctx->location == DWARF_VALUE_REGISTER)
              result = (ctx->read_reg) (ctx->baton, dwarf_expr_fetch (ctx, 0));
            else
-             error (_("Not implemented: computing frame base using explicit value operator"));
+             error (_("Not implemented: computing frame "
+                      "base using explicit value operator"));
            result = result + offset;
            in_stack_memory = 1;
            ctx->stack_len = before_stack_len;
@@ -623,7 +651,8 @@ execute_stack_op (struct dwarf_expr_context *ctx,
            struct dwarf_stack_value t1, t2;
 
            if (ctx->stack_len < 2)
-              error (_("Not enough elements for DW_OP_swap. Need 2, have %d."),
+              error (_("Not enough elements for "
+                       "DW_OP_swap.  Need 2, have %d."),
                      ctx->stack_len);
            t1 = ctx->stack[ctx->stack_len - 1];
            t2 = ctx->stack[ctx->stack_len - 2];
@@ -642,7 +671,8 @@ execute_stack_op (struct dwarf_expr_context *ctx,
            struct dwarf_stack_value t1, t2, t3;
 
            if (ctx->stack_len < 3)
-              error (_("Not enough elements for DW_OP_rot. Need 3, have %d."),
+              error (_("Not enough elements for "
+                       "DW_OP_rot.  Need 3, have %d."),
                      ctx->stack_len);
            t1 = ctx->stack[ctx->stack_len - 1];
            t2 = ctx->stack[ctx->stack_len - 2];
@@ -792,7 +822,7 @@ execute_stack_op (struct dwarf_expr_context *ctx,
        case DW_OP_GNU_push_tls_address:
          /* Variable is at a constant offset in the thread-local
          storage block into the objfile for the current thread and
-         the dynamic linker module containing this expression. Here
+         the dynamic linker module containing this expression.  Here
          we return returns the offset from that base.  The top of the
          stack has the offset from the beginning of the thread
          control block at which the variable is located.  Nothing
@@ -881,9 +911,16 @@ execute_stack_op (struct dwarf_expr_context *ctx,
 
       /* Most things push a result value.  */
       dwarf_expr_push (ctx, result, in_stack_memory);
-    no_push:;
+    no_push:
+      ;
     }
 
+  /* To simplify our main caller, if the result is an implicit
+     pointer, then make a pieced value.  This is ok because we can't
+     have implicit pointers in contexts where pieces are invalid.  */
+  if (ctx->location == DWARF_VALUE_IMPLICIT_POINTER)
+    add_piece (ctx, 8 * ctx->addr_size, 0);
+
   ctx->recursion_depth--;
   gdb_assert (ctx->recursion_depth >= 0);
 #undef sign_ext