Support 64-bit double and 64-bit long double configurations.

gcc/
	Support 64-bit double and 64-bit long double configurations.

	PR target/92055
	* config.gcc (tm_defines) [avr]: Set from --with-double=,
	--with-long-double=.
	* config/avr/t-multilib: Remove.
	* config/avr/t-avr: Output of genmultilib.awk is now fully
	dynamically generated and no more part of the repo.
	(HAVE_DOUBLE_MULTILIB, HAVE_LONG_DOUBLE_MULTILIB): New variables.
	Pass them down to...
	* config/avr/genmultilib.awk: ...here and handle them.
	* gcc/config/avr/avr.opt (-mdouble=, avr_double). New option and var.
	(-mlong-double=, avr_long_double). New option and var.
	* common/config/avr/avr-common.c (opts.h, diagnostic.h): Include.
	(TARGET_OPTION_OPTIMIZATION_TABLE) <-mdouble=, -mlong-double=>:
	Set default as requested by --with-double=
	(TARGET_HANDLE_OPTION): Define to this...
	(avr_handle_option): ...new hook worker.
	* config/avr/avr.h (DOUBLE_TYPE_SIZE): Define to avr_double.
	(LONG_DOUBLE_TYPE_SIZE): Define to avr_long_double.
	(avr_double_lib): New proto for spec function.
	(EXTRA_SPEC_FUNCTIONS) <double-lib>: Add.
	(DRIVER_SELF_SPECS): Call %:double-lib.
	* config/avr/avr.c (avr_option_override): Assert
	sizeof(long double) >= sizeof(double) for the target.
	* config/avr/avr-c.c (avr_cpu_cpp_builtins)
	[__HAVE_DOUBLE_MULTILIB__, __HAVE_LONG_DOUBLE_MULTILIB__]
	[__HAVE_DOUBLE64__, __HAVE_DOUBLE32__, __DEFAULT_DOUBLE__=]
	[__HAVE_LONG_DOUBLE64__, __HAVE_LONG_DOUBLE32__]
	[__HAVE_LONG_DOUBLE_IS_DOUBLE__, __DEFAULT_LONG_DOUBLE__=]:
	New built-in define depending on --with-double=, --with-long-double=.
	* config/avr/driver-avr.c (avr_double_lib): New spec function.
	* doc/invoke.tex (AVR Options) <-mdouble=,-mlong-double=>: Doc.
	* doc/install.texi (Cross-Compiler-Specific Options)
	<--with-double=, --with-long-double=>: Doc.

libgcc/
	Support 64-bit double and 64-bit long double configurations.

	PR target/92055
	* config/avr/t-avr (HOST_LIBGCC2_CFLAGS): Only add -DF=SF if
	long double is a 32-bit type.
	* config/avr/t-avrlibc: Copy double64 and long-double64
	multilib(s) from the vanilla one.
	* config/avr/t-copy-libgcc: New Makefile snip.

From-SVN: r277908

1 files changed, 36 insertions, 3 deletions

diff --git a/gcc/doc/install.texi b/gcc/doc/install.texi
index 55ef4ca7f24..2cb8a342a2c 100644
--- a/gcc/doc/install.texi
+++ b/gcc/doc/install.texi
@@ -2276,16 +2276,49 @@ being used as the target C library.  This causes @code{__eprintf} to be
 omitted from @file{libgcc.a} on the assumption that it will be provided by
 @samp{newlib}.
 
+@html
+<a name="avr"></a>
+@end html
 @item --with-avrlibc
-Specifies that @samp{AVR-Libc} is
-being used as the target C library.  This causes float support
+Only supported for the AVR target. Specifies that @samp{AVR-Libc} is
+being used as the target C@tie{} library.  This causes float support
 functions like @code{__addsf3} to be omitted from @file{libgcc.a} on
 the assumption that it will be provided by @file{libm.a}.  For more
 technical details, cf. @uref{http://gcc.gnu.org/PR54461,,PR54461}.
-This option is only supported for the AVR target.  It is not supported for
+It is not supported for
 RTEMS configurations, which currently use newlib.  The option is
 supported since version 4.7.2 and is the default in 4.8.0 and newer.
 
+@item --with-double=@{32|64|32,64|64,32@}
+@itemx --with-long-double=@{32|64|32,64|64,32|double@}
+Only supported for the AVR target since version@tie{}10.
+Specify the default layout available for the C/C++ @samp{double}
+and @samp{long double} type, respectively. The following rules apply:
+@itemize
+@item
+The first value after the @samp{=} specifies the default layout (in bits)
+of the type and also the default for the @option{-mdouble=} resp.
+@option{-mlong-double=} compiler option.
+@item
+If more than one value is specified, respective multilib variants are
+available, and  @option{-mdouble=} resp. @option{-mlong-double=} acts
+as a multilib option.
+@item
+If @option{--with-long-double=double} is specified, @samp{double} and
+@samp{long double} will have the same layout.
+@item
+If the configure option is not set, it defaults to @samp{32} which
+is compatible with older versions of the compiler that use non-standard
+32-bit types for @samp{double} and @samp{long double}.
+@end itemize
+Not all combinations of @option{--with-double=} and
+@option{--with-long-double=} are valid.  For example, the combination
+@option{--with-double=32,64} @option{--with-long-double=32} will be
+rejected because the first option specifies the availability of
+multilibs for @samp{double}, whereas the second option implies
+that @samp{long double} --- and hence also @samp{double} --- is always
+32@tie{}bits wide.
+
 @item --with-nds32-lib=@var{library}
 Specifies that @var{library} setting is used for building @file{libgcc.a}.
 Currently, the valid @var{library} is @samp{newlib} or @samp{mculib}.