libgcc: Enable XF mode conversions to/from DFP modes only if supported

Some targets do not support XF mode (eg AArch64), so don't build the
corresponding to/from DFP modes convertion routines if
__LIBGCC_HAS_XF_MODE__ is not defined.

2022-03-31  Christophe Lyon  <christophe.lyon@arm.com>

	libgcc/config/libbid/
	* _dd_to_xf.c: Check __LIBGCC_HAS_XF_MODE__.
	* _sd_to_xf.c: Likewise.
	* _td_to_xf.c: Likewise.
	* _xf_to_dd.c: Likewise.
	* _xf_to_sd.c: Likewise.
	* _xf_to_td.c: Likewise.

libgcc/config/libbid/_dd_to_xf.c

@@ -25,6 +25,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 XFtype
 __bid_extendddxf (_Decimal64 x) {
   XFtype res;
@@ -34,3 +35,4 @@ __bid_extendddxf (_Decimal64 x) {
   res = __bid64_to_binary80 (ux.i);
   return (res);
 }
+#endif

libgcc/config/libbid/_sd_to_xf.c

@@ -25,6 +25,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 XFtype
 __bid_extendsdxf (_Decimal32 x) {
   XFtype res;
@@ -34,3 +35,4 @@ __bid_extendsdxf (_Decimal32 x) {
   res = __bid32_to_binary80 (ux.i);
   return (res);
 }
+#endif

libgcc/config/libbid/_td_to_xf.c

@@ -25,6 +25,7 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 XFtype
 __bid_trunctdxf (_Decimal128 x) {
   XFtype res;
@@ -34,3 +35,4 @@ __bid_trunctdxf (_Decimal128 x) {
   res = __bid128_to_binary80 (ux.i);
   return (res);
 }
+#endif

libgcc/config/libbid/_xf_to_dd.c

@@ -25,9 +25,11 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 _Decimal64
 __bid_truncxfdd (XFtype x) {
   union decimal64 res;
   res.i = __binary80_to_bid64 (x);
   return (res.d);
 }
+#endif

libgcc/config/libbid/_xf_to_sd.c

@@ -25,9 +25,11 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 _Decimal32
 __bid_truncxfsd (XFtype x) {
   union decimal32 res;
   res.i = __binary80_to_bid32 (x);
   return (res.d);
 }
+#endif

libgcc/config/libbid/_xf_to_td.c

@@ -25,9 +25,11 @@ see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
 #include "bid_functions.h"
 #include "bid_gcc_intrinsics.h"
 
+#ifdef __LIBGCC_HAS_XF_MODE__
 _Decimal128
 __bid_extendxftd (XFtype x) {
   union decimal128 res;
   res.i = __binary80_to_bid128 (x);
   return (res.d);
 }
+#endif