Move dwarf_call to dwarf_expr_context

Following the idea of merging the evaluators, the dwarf_call and
get_frame_pc method can be moved from dwarf_expr_executor and
dwarf_evaluate_loc_desc classes to their base class dwarf_expr_context.
Once this is done, the get_frame_pc can be replace with lambda
function.

gdb/ChangeLog:

	* dwarf2/expr.c (dwarf_expr_context::dwarf_call): Move from
	dwarf_evaluate_loc_desc.
	(dwarf_expr_context::get_frame_pc): Replace with lambda.
	* dwarf2/expr.h (dwarf_expr_context::get_frame_pc): Remove
	method.
	* dwarf2/frame.c (dwarf_expr_executor::dwarf_call): Remove
	method.
	(dwarf_expr_executor::get_frame_pc): Remove method.
	* dwarf2/loc.c (dwarf_evaluate_loc_desc::get_frame_pc): Remove
	method.
	(dwarf_evaluate_loc_desc::dwarf_call): Move to
	dwarf_expr_context.
	(per_cu_dwarf_call): Inline function.

Change-Id: Ib0b6048e9b264e54cfdbd8dd76f91cd3f76af673

4 files changed, 33 insertions, 70 deletions

diff --git a/gdb/dwarf2/expr.c b/gdb/dwarf2/expr.c
index 29f5f977ace..a5144b692df 100644
--- a/gdb/dwarf2/expr.c
+++ b/gdb/dwarf2/expr.c
@@ -237,6 +237,31 @@ dwarf_expr_context::get_base_type (cu_offset die_cu_off, int size)
   return result;
 }
 
+/* See expr.h.  */
+
+void
+dwarf_expr_context::dwarf_call (cu_offset die_cu_off)
+{
+  ensure_have_per_cu (per_cu, "DW_OP_call");
+
+  struct frame_info *frame = this->frame;
+
+  auto get_pc_from_frame = [frame] ()
+    {
+      ensure_have_frame (frame, "DW_OP_call");
+      return get_frame_address_in_block (frame);
+    };
+
+  struct dwarf2_locexpr_baton block
+    = dwarf2_fetch_die_loc_cu_off (die_cu_off, per_cu, per_objfile,
+				   get_pc_from_frame);
+
+  /* DW_OP_call_ref is currently not supported.  */
+  gdb_assert (block.per_cu == per_cu);
+
+  this->eval (block.data, block.size);
+}
+
 /* Require that TYPE be an integral type; throw an exception if not.  */
 
 static void
@@ -1279,7 +1304,8 @@ dwarf_expr_context::execute_stack_op (const gdb_byte *op_ptr,
 	  returned.  */
 	  result = value_as_long (fetch (0));
 	  pop ();
-	  result = this->get_tls_address (result);
+	  result = target_translate_tls_address (this->per_objfile->objfile,
+						 result);
 	  result_val = value_from_ulongest (address_type, result);
 	  break;
 
diff --git a/gdb/dwarf2/expr.h b/gdb/dwarf2/expr.h
index e17cd99c256..eb765a28a26 100644
--- a/gdb/dwarf2/expr.h
+++ b/gdb/dwarf2/expr.h
@@ -195,22 +195,6 @@ struct dwarf_expr_context
   /* Read LENGTH bytes at ADDR into BUF.  */
   virtual void read_mem (gdb_byte *buf, CORE_ADDR addr, size_t length) = 0;
 
-  /* Return the PC for the frame.  */
-  virtual CORE_ADDR get_frame_pc ()
-  {
-    error (_("%s is invalid in this context"), "DW_OP_implicit_pointer");
-  }
-
-  /* Return the thread-local storage address for
-     DW_OP_GNU_push_tls_address or DW_OP_form_tls_address.  */
-  virtual CORE_ADDR get_tls_address (CORE_ADDR offset) = 0;
-
-  /* Execute DW_AT_location expression for the DWARF expression
-     subroutine in the DIE at DIE_CU_OFF in the CU.  Do not touch
-     STACK while it being passed to and returned from the called DWARF
-     subroutine.  */
-  virtual void dwarf_call (cu_offset die_cu_off) = 0;
-
   /* Push on DWARF stack an entry evaluated for DW_TAG_call_site's
      parameter matching KIND and KIND_U at the caller of specified BATON.
      If DEREF_SIZE is not -1 then use DW_AT_call_data_value instead of
@@ -247,6 +231,12 @@ private:
      represent a base type.  SIZE is non-zero if this function should
      verify that the resulting type has the correct size.  */
   struct type *get_base_type (cu_offset die_cu_off, int size);
+
+  /* Execute DW_AT_location expression for the DWARF expression
+     subroutine in the DIE at DIE_CU_OFF in the CU.  Do not touch
+     STACK while it being passed to and returned from the called DWARF
+     subroutine.  */
+  void dwarf_call (cu_offset die_cu_off);
 };
 
 /* Return the value of register number REG (a DWARF register number),
diff --git a/gdb/dwarf2/frame.c b/gdb/dwarf2/frame.c
index c93ec5d5a60..af5302bd980 100644
--- a/gdb/dwarf2/frame.c
+++ b/gdb/dwarf2/frame.c
@@ -248,16 +248,6 @@ public:
     invalid ("DW_OP_push_object_address");
   }
 
-  CORE_ADDR get_tls_address (CORE_ADDR offset) override
-  {
-    invalid ("DW_OP_form_tls_address");
-  }
-
-  void dwarf_call (cu_offset die_offset) override
-  {
-    invalid ("DW_OP_call*");
-  }
-
  private:
 
   void invalid (const char *op) ATTRIBUTE_NORETURN
diff --git a/gdb/dwarf2/loc.c b/gdb/dwarf2/loc.c
index 21e43e399c1..5a2b1b2851c 100644
--- a/gdb/dwarf2/loc.c
+++ b/gdb/dwarf2/loc.c
@@ -600,26 +600,6 @@ func_get_frame_base_dwarf_block (struct symbol *framefunc, CORE_ADDR pc,
 	   framefunc->natural_name ());
 }
 
-static void
-per_cu_dwarf_call (struct dwarf_expr_context *ctx, cu_offset die_offset,
-		   dwarf2_per_cu_data *per_cu, dwarf2_per_objfile *per_objfile)
-{
-  struct dwarf2_locexpr_baton block;
-
-  auto get_frame_pc_from_ctx = [ctx] ()
-    {
-      return ctx->get_frame_pc ();
-    };
-
-  block = dwarf2_fetch_die_loc_cu_off (die_offset, per_cu, per_objfile,
-				       get_frame_pc_from_ctx);
-
-  /* DW_OP_call_ref is currently not supported.  */
-  gdb_assert (block.per_cu == per_cu);
-
-  ctx->eval (block.data, block.size);
-}
-
 /* See loc.h.  */
 
 struct value *
@@ -654,29 +634,6 @@ public:
 
   CORE_ADDR obj_address;
 
-  /* Helper function for dwarf2_evaluate_loc_desc.  Computes the PC for
-     the frame in BATON.  */
-
-  CORE_ADDR get_frame_pc () override
-  {
-    return get_frame_address_in_block (frame);
-  }
-
-  /* Using the objfile specified in BATON, find the address for the
-     current thread's thread-local storage with offset OFFSET.  */
-  CORE_ADDR get_tls_address (CORE_ADDR offset) override
-  {
-    return target_translate_tls_address (per_objfile->objfile, offset);
-  }
-
-  /* Helper interface of per_cu_dwarf_call for
-     dwarf2_evaluate_loc_desc.  */
-
-  void dwarf_call (cu_offset die_offset) override
-  {
-    per_cu_dwarf_call (this, die_offset, per_cu, per_objfile);
-  }
-
   /* Callback function for get_object_address. Return the address of the VLA
      object.  */