(tune_flags): New variable.

(tune_flags): New variable.
(target_{cpu,fpe}_name): Delete.
(arm_fpu_arch): New variable.
(arm_select): Also allow -march=... to configure just the
architecture.
(all_procs): Allow armv{2,2a,3,3m,4,4t} for use with -march=.
(arm_override_options): Handle -march=, but don't let -mcpu=
and -mtune= match the architecture names, since we can only
tune for an implementation.  Rework selection of tuning options
for floating point.
(use_return_insn): Support interworking with Thumb code.
(arm_rtx_costs): Rework multiply costs so that cost is based on
the tune, not the architecture.
(f_register_operand): New function.
(output_return_instruction): Support interworking with Thumb code.
(output_func_epilogue): Support interworking with Thumb code.
Remove redundant calculation of code_size. Use floating-point
load-multiples if permitted.
(emit_sfm): New function.
(arm_expand_prologue): Use floating-point store-multiples if
permitted.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@14457 138bc75d-0d04-0410-961f-82ee72b054a4