Target FP: Add string routines to target-float.{c,h}

This adds target_float_to_string and target_float_from_string,
which dispatch to the corresponding floatformat_ or decimal_ routines.

Existing users of those routines are changed to use the new
target-float routines instead (most of those places already handle
both binary and decimal FP).

In addition, two other places are changes to use target_float_from_string:

- define_symbol in stabsread.c, when parsing a floating-point literal
  from stabs debug info

- gdbarch-selftest.c when initializing a target format values (to
  eliminate use of DOUBLEST there).

gdb/ChangeLog:
2017-11-06  Ulrich Weigand  <uweigand@de.ibm.com>

	* target-float.c (target_float_to_string): New function.
	(target_float_from_string): New function.
	* target-float.h (target_float_to_string): Add prototype.
	(target_float_from_string): Add prototype.

	* valprint.c: Include "target-float.h".  Do not include
	"doublest.h" and "dfp.h".
	(print_floating): Use target_float_to_string.
	* printcmd.c: Include "target-float.h".  Do not include "dfp.h".
	(printf_floating): Use target_float_to_string.
	* i387-tdep.c: Include "target-float.h".  Do not include "doublest.h".
	(print_i387_value): Use target_float_to_string.
	* mips-tdep.c: Include "target-float.h".
	(mips_print_fp_register): Use target_float_to_string.
	* sh64-tdep.c: Include "target-float.h".
	(sh64_do_fp_register): Use target_float_to_string.

	* parse.c: Include "target-float.h".  Do not include
	"doublest.h" and "dfp.h".
	(parse_float): Use target_float_from_string.
	* stabsread.c: Include "target-float.h".  Do not include "doublest.h".
	(define_symbol): Use target_float_from_string.
	* gdbarch-selftests.c: Include "target-float.h".
	(register_to_value_test): Use target_float_from_string.

1 files changed, 37 insertions, 0 deletions

diff --git a/gdb/target-float.c b/gdb/target-float.c
index a082b9c..e90cf03 100644
--- a/gdb/target-float.c
+++ b/gdb/target-float.c
@@ -60,3 +60,40 @@ target_float_is_zero (const gdb_byte *addr, const struct type *type)
   gdb_assert_not_reached ("unexpected type code");
 }
 
+/* Convert the byte-stream ADDR, interpreted as floating-point type TYPE,
+   to a string, optionally using the print format FORMAT.  */
+std::string
+target_float_to_string (const gdb_byte *addr, const struct type *type,
+			const char *format)
+{
+  if (TYPE_CODE (type) == TYPE_CODE_FLT)
+    return floatformat_to_string (floatformat_from_type (type), addr, format);
+
+  if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT)
+    return decimal_to_string (addr, TYPE_LENGTH (type),
+			      gdbarch_byte_order (get_type_arch (type)),
+			      format);
+
+  gdb_assert_not_reached ("unexpected type code");
+}
+
+/* Parse string STRING into a target floating-number of type TYPE and
+   store it as byte-stream ADDR.  Return whether parsing succeeded.  */
+bool
+target_float_from_string (gdb_byte *addr, const struct type *type,
+			  const std::string &string)
+{
+  /* Ensure possible padding bytes in the target buffer are zeroed out.  */
+  memset (addr, 0, TYPE_LENGTH (type));
+
+  if (TYPE_CODE (type) == TYPE_CODE_FLT)
+    return floatformat_from_string (floatformat_from_type (type), addr,
+				    string);
+
+  if (TYPE_CODE (type) == TYPE_CODE_DECFLOAT)
+    return decimal_from_string (addr, TYPE_LENGTH (type),
+				gdbarch_byte_order (get_type_arch (type)),
+				string);
+
+  gdb_assert_not_reached ("unexpected type code");
+}