(mips_isa_string): Add mips4 to comment.

(mips_isa_string): Add mips4 to comment.

(large_int): Delete code for handling 64 bit constants.
(mips_const_double_ok): For irix6, reject all floating point constants.
(mips_move_2words): Use dli not li for 64 bit constants.
Use dla not la for 64 bit addresses.
(output_block_move): Likewise.
(function_arg): Add support for 64bit ABI.
(override_options): Add support for mips4 and R8000.
(print_operand): Handle new modifiers 'B', 'b', 'T', 't'.
Make 'X' case work for 64 bit host.
(mips_output_filename): Use ASM_OUTPUT_FILENAME.
(mips_asm_file_start): Go to text section for 64bit ABI.
(compure_frame_size, save_restore_insns, function_prologue,
mips_expand_prologue, function_epilogue): Add support for 64 bit ABI.
(type_dependent_reg, mips_function_value): New functions.

From-SVN: r8863