Add accessors for members of complex numbers

This introduces two new functions that make it simpler to access the
components of a complex number.

gdb/ChangeLog
2020-04-01  Tom Tromey  <tom@tromey.com>

	* valprint.c (generic_value_print_complex): Use accessors.
	* value.h (value_real_part, value_imaginary_part): Declare.
	* valops.c (value_real_part, value_imaginary_part): New
	functions.
	* value.c (creal_internal_fn, cimag_internal_fn): Use accessors.

5 files changed, 45 insertions, 10 deletions

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index 7a883e8..d1f408f 100644
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,5 +1,13 @@
 2020-04-01  Tom Tromey  <tom@tromey.com>
 
+	* valprint.c (generic_value_print_complex): Use accessors.
+	* value.h (value_real_part, value_imaginary_part): Declare.
+	* valops.c (value_real_part, value_imaginary_part): New
+	functions.
+	* value.c (creal_internal_fn, cimag_internal_fn): Use accessors.
+
+2020-04-01  Tom Tromey  <tom@tromey.com>
+
 	* stabsread.c (rs6000_builtin_type, read_sun_floating_type)
 	(read_range_type): Update.
 	* mdebugread.c (basic_type): Update.
diff --git a/gdb/valops.c b/gdb/valops.c
index d484746..83fd258 100644
--- a/gdb/valops.c
+++ b/gdb/valops.c
@@ -3877,6 +3877,31 @@ value_literal_complex (struct value *arg1,
   return val;
 }
 
+/* See value.h.  */
+
+struct value *
+value_real_part (struct value *value)
+{
+  struct type *type = check_typedef (value_type (value));
+  struct type *ttype = TYPE_TARGET_TYPE (type);
+
+  gdb_assert (TYPE_CODE (type) == TYPE_CODE_COMPLEX);
+  return value_from_component (value, ttype, 0);
+}
+
+/* See value.h.  */
+
+struct value *
+value_imaginary_part (struct value *value)
+{
+  struct type *type = check_typedef (value_type (value));
+  struct type *ttype = TYPE_TARGET_TYPE (type);
+
+  gdb_assert (TYPE_CODE (type) == TYPE_CODE_COMPLEX);
+  return value_from_component (value, ttype,
+			       TYPE_LENGTH (check_typedef (ttype)));
+}
+
 /* Cast a value into the appropriate complex data type.  */
 
 static struct value *
diff --git a/gdb/valprint.c b/gdb/valprint.c
index 108a21b..80b7514 100644
--- a/gdb/valprint.c
+++ b/gdb/valprint.c
@@ -811,16 +811,11 @@ generic_value_print_complex (struct value *val, struct ui_file *stream,
 {
   fprintf_filtered (stream, "%s", decorations->complex_prefix);
 
-  struct type *type = check_typedef (value_type (val));
-  struct value *real_part
-    = value_from_component (val, TYPE_TARGET_TYPE (type), 0);
+  struct value *real_part = value_real_part (val);
   value_print_scalar_formatted (real_part, options, 0, stream);
   fprintf_filtered (stream, "%s", decorations->complex_infix);
 
-  struct value *imag_part
-    = value_from_component (val, TYPE_TARGET_TYPE (type),
-			    TYPE_LENGTH (TYPE_TARGET_TYPE (type)));
-
+  struct value *imag_part = value_imaginary_part (val);
   value_print_scalar_formatted (imag_part, options, 0, stream);
   fprintf_filtered (stream, "%s", decorations->complex_suffix);
 }
diff --git a/gdb/value.c b/gdb/value.c
index ceaeb83..f722c27 100644
--- a/gdb/value.c
+++ b/gdb/value.c
@@ -3962,7 +3962,7 @@ creal_internal_fn (struct gdbarch *gdbarch,
   type *ctype = check_typedef (value_type (cval));
   if (TYPE_CODE (ctype) != TYPE_CODE_COMPLEX)
     error (_("expected a complex number"));
-  return value_from_component (cval, TYPE_TARGET_TYPE (ctype), 0);
+  return value_real_part (cval);
 }
 
 /* Implementation of the convenience function $_cimag.  Extracts the
@@ -3981,8 +3981,7 @@ cimag_internal_fn (struct gdbarch *gdbarch,
   type *ctype = check_typedef (value_type (cval));
   if (TYPE_CODE (ctype) != TYPE_CODE_COMPLEX)
     error (_("expected a complex number"));
-  return value_from_component (cval, TYPE_TARGET_TYPE (ctype),
-			       TYPE_LENGTH (TYPE_TARGET_TYPE (ctype)));
+  return value_imaginary_part (cval);
 }
 
 #if GDB_SELF_TEST
diff --git a/gdb/value.h b/gdb/value.h
index e4fd258..85fe6c2 100644
--- a/gdb/value.h
+++ b/gdb/value.h
@@ -1141,6 +1141,14 @@ extern struct value *value_slice (struct value *, int, int);
 extern struct value *value_literal_complex (struct value *, struct value *,
 					    struct type *);
 
+/* Return the real part of a complex value.  */
+
+extern struct value *value_real_part (struct value *value);
+
+/* Return the imaginary part of a complex value.  */
+
+extern struct value *value_imaginary_part (struct value *value);
+
 extern struct value *find_function_in_inferior (const char *,
 						struct objfile **);