[09/19] agent expression routines

["Ulrich Weigand" <uweigand at de dot ibm dot com>]

Hello,

this patch removes the last remaining instances of current_gdbarch
in the agent expression code: one instance in ax-gdb.c itself and
one in the DWARF-2 implementation of the tracepoint_var_ref callback
(this is at the same time the last remaining instance in any of the
symbol readers).

In both cases, the expression architecture of the GDB expression for
which the agent expression is being constructed is passed through.

Bye,
Ulrich


ChangeLog:

	* ax-gdb.c (gen_bitfield_ref): Add EXP argument, use expression
	architecture instead of current_gdbarch.
	(gen_struct_ref): Add EXP argument, pass to get_bitfield_ref.
	(gen_expr): Pass expression to get_struct_ref.

	* symtab.h (struct symbol_ops): Add GDBARCH parameter to
	tracepoint_var_ref callback.
	* ax-gdb.c (gen_var_ref): Pass architecture to tracepoint_var_ref
	symbol operation callback.
	* dwarf2loc.c (dwarf2_tracepoint_var_ref): Add GDBARCH parameter.
	Use it instead of current_gdbarch.
	(locexpr_tracepoint_var_ref): Add GDBARCH parameter.  Pass it to
	dwarf2_tracepoint_var_ref.
	(loclist_tracepoint_var_ref): Likewise.


Index: gdb-head/gdb/ax-gdb.c
===================================================================
--- gdb-head.orig/gdb/ax-gdb.c
+++ gdb-head/gdb/ax-gdb.c
@@ -124,10 +124,10 @@ static void gen_complement (struct agent
 static void gen_deref (struct agent_expr *, struct axs_value *);
 static void gen_address_of (struct agent_expr *, struct axs_value *);
 static int find_field (struct type *type, char *name);
-static void gen_bitfield_ref (struct agent_expr *ax,
+static void gen_bitfield_ref (struct expression *exp, struct agent_expr *ax,
 			      struct axs_value *value,
 			      struct type *type, int start, int end);
-static void gen_struct_ref (struct agent_expr *ax,
+static void gen_struct_ref (struct expression *exp, struct agent_expr *ax,
 			    struct axs_value *value,
 			    char *field,
 			    char *operator_name, char *operand_name);
@@ -623,7 +623,7 @@ gen_var_ref (struct gdbarch *gdbarch, st
 	 Unfortunately DWARF 2 stores the frame-base (instead of the
 	 function) location in a function's symbol.  Oops!  For the
 	 moment enable this when/where applicable.  */
-      SYMBOL_COMPUTED_OPS (var)->tracepoint_var_ref (var, ax, value);
+      SYMBOL_COMPUTED_OPS (var)->tracepoint_var_ref (var, gdbarch, ax, value);
       break;
 
     case LOC_OPTIMIZED_OUT:
@@ -1147,8 +1147,9 @@ find_field (struct type *type, char *nam
    starting and one-past-ending *bit* numbers of the field within the
    structure.  */
 static void
-gen_bitfield_ref (struct agent_expr *ax, struct axs_value *value,
-		  struct type *type, int start, int end)
+gen_bitfield_ref (struct expression *exp, struct agent_expr *ax,
+		  struct axs_value *value, struct type *type,
+		  int start, int end)
 {
   /* Note that ops[i] fetches 8 << i bits.  */
   static enum agent_op ops[]
@@ -1274,7 +1275,7 @@ gen_bitfield_ref (struct agent_expr *ax,
 	     the sign/zero extension will wipe them out.
 	     - If we're in the interior of the word, then there is no garbage
 	     on either end, because the ref operators zero-extend.  */
-	  if (gdbarch_byte_order (current_gdbarch) == BFD_ENDIAN_BIG)
+	  if (gdbarch_byte_order (exp->gdbarch) == BFD_ENDIAN_BIG)
 	    gen_left_shift (ax, end - (offset + op_size));
 	  else
 	    gen_left_shift (ax, offset - start);
@@ -1308,7 +1309,8 @@ gen_bitfield_ref (struct agent_expr *ax,
    the operator being compiled, and OPERAND_NAME is the kind of thing
    it operates on; we use them in error messages.  */
 static void
-gen_struct_ref (struct agent_expr *ax, struct axs_value *value, char *field,
+gen_struct_ref (struct expression *exp, struct agent_expr *ax,
+		struct axs_value *value, char *field,
 		char *operator_name, char *operand_name)
 {
   struct type *type;
@@ -1339,7 +1341,7 @@ gen_struct_ref (struct agent_expr *ax, s
 
   /* Is this a bitfield?  */
   if (TYPE_FIELD_PACKED (type, i))
-    gen_bitfield_ref (ax, value, TYPE_FIELD_TYPE (type, i),
+    gen_bitfield_ref (exp, ax, value, TYPE_FIELD_TYPE (type, i),
 		      TYPE_FIELD_BITPOS (type, i),
 		      (TYPE_FIELD_BITPOS (type, i)
 		       + TYPE_FIELD_BITSIZE (type, i)));
@@ -1698,9 +1700,9 @@ gen_expr (struct expression *exp, union 
 	(*pc) += 4 + BYTES_TO_EXP_ELEM (length + 1);
 	gen_expr (exp, pc, ax, value);
 	if (op == STRUCTOP_STRUCT)
-	  gen_struct_ref (ax, value, name, ".", "structure or union");
+	  gen_struct_ref (exp, ax, value, name, ".", "structure or union");
 	else if (op == STRUCTOP_PTR)
-	  gen_struct_ref (ax, value, name, "->",
+	  gen_struct_ref (exp, ax, value, name, "->",
 			  "pointer to a structure or union");
 	else
 	  /* If this `if' chain doesn't handle it, then the case list
Index: gdb-head/gdb/dwarf2loc.c
===================================================================
--- gdb-head.orig/gdb/dwarf2loc.c
+++ gdb-head/gdb/dwarf2loc.c
@@ -366,9 +366,9 @@ dwarf2_loc_desc_needs_frame (gdb_byte *d
 }
 
 static void
-dwarf2_tracepoint_var_ref (struct symbol *symbol, struct agent_expr *ax,
-			   struct axs_value *value, gdb_byte *data,
-			   int size)
+dwarf2_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch,
+			   struct agent_expr *ax, struct axs_value *value,
+			   gdb_byte *data, int size)
 {
   if (size == 0)
     error (_("Symbol \"%s\" has been optimized out."),
@@ -401,7 +401,7 @@ dwarf2_tracepoint_var_ref (struct symbol
 	error (_("Unexpected opcode after DW_OP_fbreg for symbol \"%s\"."),
 	       SYMBOL_PRINT_NAME (symbol));
 
-      gdbarch_virtual_frame_pointer (current_gdbarch, 
+      gdbarch_virtual_frame_pointer (gdbarch,
 				     ax->scope, &frame_reg, &frame_offset);
       ax_reg (ax, frame_reg);
       ax_const_l (ax, frame_offset);
@@ -522,12 +522,13 @@ locexpr_describe_location (struct symbol
    against.  When there is one this function should be revisited.  */
 
 static void
-locexpr_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax,
-			    struct axs_value * value)
+locexpr_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch,
+			    struct agent_expr *ax, struct axs_value *value)
 {
   struct dwarf2_locexpr_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
 
-  dwarf2_tracepoint_var_ref (symbol, ax, value, dlbaton->data, dlbaton->size);
+  dwarf2_tracepoint_var_ref (symbol, gdbarch, ax, value,
+			     dlbaton->data, dlbaton->size);
 }
 
 /* The set of location functions used with the DWARF-2 expression
@@ -594,8 +595,8 @@ loclist_describe_location (struct symbol
 /* Describe the location of SYMBOL as an agent value in VALUE, generating
    any necessary bytecode in AX.  */
 static void
-loclist_tracepoint_var_ref (struct symbol * symbol, struct agent_expr * ax,
-			    struct axs_value * value)
+loclist_tracepoint_var_ref (struct symbol *symbol, struct gdbarch *gdbarch,
+			    struct agent_expr *ax, struct axs_value *value)
 {
   struct dwarf2_loclist_baton *dlbaton = SYMBOL_LOCATION_BATON (symbol);
   gdb_byte *data;
@@ -605,7 +606,7 @@ loclist_tracepoint_var_ref (struct symbo
   if (data == NULL)
     error (_("Variable \"%s\" is not available."), SYMBOL_NATURAL_NAME (symbol));
 
-  dwarf2_tracepoint_var_ref (symbol, ax, value, data, size);
+  dwarf2_tracepoint_var_ref (symbol, gdbarch, ax, value, data, size);
 }
 
 /* The set of location functions used with the DWARF-2 expression
Index: gdb-head/gdb/symtab.h
===================================================================
--- gdb-head.orig/gdb/symtab.h
+++ gdb-head/gdb/symtab.h
@@ -527,8 +527,8 @@ struct symbol_computed_ops
      the caller will generate the right code in the process of
      treating this as an lvalue or rvalue.  */
 
-  void (*tracepoint_var_ref) (struct symbol * symbol, struct agent_expr * ax,
-			      struct axs_value * value);
+  void (*tracepoint_var_ref) (struct symbol *symbol, struct gdbarch *gdbarch,
+			      struct agent_expr *ax, struct axs_value *value);
 };
 
 /* Functions used with LOC_REGISTER and LOC_REGPARM_ADDR.  */
-- 
  Dr. Ulrich Weigand
  GNU Toolchain for Linux on System z and Cell BE
  Ulrich.Weigand@de.ibm.com