Consider addressable memory unit size in various value functions

This patch updates various value handling functions to make them
consider the addressable memory unit size of the current architecture.
This allows to correctly extract and print values on architectures whose
addressable memory unit is not 8 bits.

The patch doesn't cover all the code that would ideally need to be
adjusted, only the code paths that we happen to use, plus a few obvious
ones.  Specifically, those areas are not covered by this patch:

 - Management of unavailable bits
 - Bitfields
 - C++ stuff

Regression-tested on x86-64 Ubuntu 14.04.  I saw no related test result
change.

gdb/ChangeLog:

	* c-valprint.c (c_val_print_array): Consider addressable memory
	unit size.
	(c_val_print_ptr): Likewise.
	(c_val_print_int): Likewise.
	* findvar.c (read_frame_register_value): Likewise.
	* valarith.c (find_size_for_pointer_math): Likewise.
	(value_ptrdiff): Likewise.
	(value_subscripted_rvalue): Likewise.
	* valops.c (read_value_memory): Likewise (and rename variables).
	(value_assign): Likewise.
	(value_repeat): Likewise.
	(value_array): Likewise.
	(value_slice): Likewise.
	* valprint.c (generic_val_print_ptr): Likewise.
	(generic_val_print_enum): Likewise.
	(generic_val_print_bool): Likewise.
	(generic_val_print_int): Likewise.
	(generic_val_print_char): Likewise.
	(generic_val_print_float): Likewise.
	(generic_val_print_decfloat): Likewise.
	(generic_val_print_complex): Likewise.
	(val_print_scalar_formatted): Likewise.
	(val_print_array_elements): Likewise.
	* value.c (set_value_parent): Likewise.
	(value_contents_copy_raw): Likewise.
	(set_internalvar_component): Likewise.
	(value_primitive_field): Likewise.
	(value_fetch_lazy): Likewise.
	* value.h (read_value_memory): Update comment.

1 files changed, 40 insertions, 13 deletions

diff --git a/gdb/valprint.c b/gdb/valprint.c
index 8893830..713998c 100644
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -433,6 +433,9 @@ generic_val_print_ptr (struct type *type, const gdb_byte *valaddr,
 		       const struct value *original_value,
 		       const struct value_print_options *options)
 {
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
+
   if (options->format && options->format != 's')
     {
       val_print_scalar_formatted (type, valaddr, embedded_offset,
@@ -442,7 +445,8 @@ generic_val_print_ptr (struct type *type, const gdb_byte *valaddr,
     {
       struct type *unresolved_elttype = TYPE_TARGET_TYPE(type);
       struct type *elttype = check_typedef (unresolved_elttype);
-      CORE_ADDR addr = unpack_pointer (type, valaddr + embedded_offset);
+      CORE_ADDR addr = unpack_pointer (type,
+				       valaddr + embedded_offset * unit_size);
 
       print_unpacked_pointer (type, elttype, addr, stream, options);
     }
@@ -520,6 +524,8 @@ generic_val_print_enum (struct type *type, const gdb_byte *valaddr,
   unsigned int i;
   unsigned int len;
   LONGEST val;
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
 
   if (options->format)
     {
@@ -528,7 +534,7 @@ generic_val_print_enum (struct type *type, const gdb_byte *valaddr,
       return;
     }
   len = TYPE_NFIELDS (type);
-  val = unpack_long (type, valaddr + embedded_offset);
+  val = unpack_long (type, valaddr + embedded_offset * unit_size);
   for (i = 0; i < len; i++)
     {
       QUIT;
@@ -633,6 +639,8 @@ generic_val_print_bool (struct type *type, const gdb_byte *valaddr,
 			const struct generic_val_print_decorations *decorations)
 {
   LONGEST val;
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
 
   if (options->format || options->output_format)
     {
@@ -644,7 +652,7 @@ generic_val_print_bool (struct type *type, const gdb_byte *valaddr,
     }
   else
     {
-      val = unpack_long (type, valaddr + embedded_offset);
+      val = unpack_long (type, valaddr + embedded_offset * unit_size);
       if (val == 0)
 	fputs_filtered (decorations->false_name, stream);
       else if (val == 1)
@@ -662,6 +670,9 @@ generic_val_print_int (struct type *type, const gdb_byte *valaddr,
 		       const struct value *original_value,
 		       const struct value_print_options *options)
 {
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
+
   if (options->format || options->output_format)
     {
       struct value_print_options opts = *options;
@@ -672,7 +683,8 @@ generic_val_print_int (struct type *type, const gdb_byte *valaddr,
 				  original_value, &opts, 0, stream);
     }
   else
-    val_print_type_code_int (type, valaddr + embedded_offset, stream);
+    val_print_type_code_int (type, valaddr + embedded_offset * unit_size,
+			     stream);
 }
 
 /* generic_val_print helper for TYPE_CODE_CHAR.  */
@@ -685,6 +697,8 @@ generic_val_print_char (struct type *type, struct type *unresolved_type,
 			const struct value_print_options *options)
 {
   LONGEST val;
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
 
   if (options->format || options->output_format)
     {
@@ -697,7 +711,7 @@ generic_val_print_char (struct type *type, struct type *unresolved_type,
     }
   else
     {
-      val = unpack_long (type, valaddr + embedded_offset);
+      val = unpack_long (type, valaddr + embedded_offset * unit_size);
       if (TYPE_UNSIGNED (type))
 	fprintf_filtered (stream, "%u", (unsigned int) val);
       else
@@ -715,6 +729,9 @@ generic_val_print_float (struct type *type, const gdb_byte *valaddr,
 			 const struct value *original_value,
 			 const struct value_print_options *options)
 {
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
+
   if (options->format)
     {
       val_print_scalar_formatted (type, valaddr, embedded_offset,
@@ -722,7 +739,7 @@ generic_val_print_float (struct type *type, const gdb_byte *valaddr,
     }
   else
     {
-      print_floating (valaddr + embedded_offset, type, stream);
+      print_floating (valaddr + embedded_offset * unit_size, type, stream);
     }
 }
 
@@ -734,11 +751,15 @@ generic_val_print_decfloat (struct type *type, const gdb_byte *valaddr,
 			    const struct value *original_value,
 			    const struct value_print_options *options)
 {
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
+
   if (options->format)
     val_print_scalar_formatted (type, valaddr, embedded_offset, original_value,
 				options, 0, stream);
   else
-    print_decimal_floating (valaddr + embedded_offset, type, stream);
+    print_decimal_floating (valaddr + embedded_offset * unit_size, type,
+			    stream);
 }
 
 /* generic_val_print helper for TYPE_CODE_COMPLEX.  */
@@ -751,22 +772,25 @@ generic_val_print_complex (struct type *type, const gdb_byte *valaddr,
 			   const struct generic_val_print_decorations
 			     *decorations)
 {
+  struct gdbarch *gdbarch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (gdbarch);
+
   fprintf_filtered (stream, "%s", decorations->complex_prefix);
   if (options->format)
     val_print_scalar_formatted (TYPE_TARGET_TYPE (type), valaddr,
 				embedded_offset, original_value, options, 0,
 				stream);
   else
-    print_floating (valaddr + embedded_offset, TYPE_TARGET_TYPE (type),
-		    stream);
+    print_floating (valaddr + embedded_offset * unit_size,
+		    TYPE_TARGET_TYPE (type), stream);
   fprintf_filtered (stream, "%s", decorations->complex_infix);
   if (options->format)
     val_print_scalar_formatted (TYPE_TARGET_TYPE (type), valaddr,
 				embedded_offset
-				+ TYPE_LENGTH (TYPE_TARGET_TYPE (type)),
+				+ type_length_units (TYPE_TARGET_TYPE (type)),
 				original_value, options, 0, stream);
   else
-    print_floating (valaddr + embedded_offset
+    print_floating (valaddr + embedded_offset * unit_size
 		    + TYPE_LENGTH (TYPE_TARGET_TYPE (type)),
 		    TYPE_TARGET_TYPE (type), stream);
   fprintf_filtered (stream, "%s", decorations->complex_suffix);
@@ -1150,6 +1174,9 @@ val_print_scalar_formatted (struct type *type,
 			    int size,
 			    struct ui_file *stream)
 {
+  struct gdbarch *arch = get_type_arch (type);
+  int unit_size = gdbarch_addressable_memory_unit_size (arch);
+
   gdb_assert (val != NULL);
   gdb_assert (valaddr == value_contents_for_printing_const (val));
 
@@ -1175,7 +1202,7 @@ val_print_scalar_formatted (struct type *type,
   else if (!value_bytes_available (val, embedded_offset, TYPE_LENGTH (type)))
     val_print_unavailable (stream);
   else
-    print_scalar_formatted (valaddr + embedded_offset, type,
+    print_scalar_formatted (valaddr + embedded_offset * unit_size, type,
 			    options, size, stream);
 }
 
@@ -1823,7 +1850,7 @@ val_print_array_elements (struct type *type,
   LONGEST low_pos, high_pos;
 
   elttype = TYPE_TARGET_TYPE (type);
-  eltlen = TYPE_LENGTH (check_typedef (elttype));
+  eltlen = type_length_units (check_typedef (elttype));
   index_type = TYPE_INDEX_TYPE (type);
 
   if (get_array_bounds (type, &low_bound, &high_bound))