invoke.texi (ARM Options): Document -mtls-dialect option.

invoke.texi (ARM Options): Document -mtls-dialect option.

	* doc/invoke.texi (ARM Options): Document -mtls-dialect option.
	* doc/install.texi (Configuration): Document --with-tls.
	* config.gcc (arm*-*-linux*): Default to gnu tls.
	(arm*-*-*): Add --with-tls option.
	(all_defaults): Add 'tls'.
	* config/arm/arm.c (enum tls_reloc): Add TLS_DESCSEQ.
	(arm_call_tls_get_addr): Clean up. Assert not tls descriptor.
	(arm_tls_descseq_addr): New.
	(legitimize_tls_address): Add tlsdesc support.
	(arm_cannot_copy_insn_p): Check for tlscall.
	(arm_emit_tls_decoration): Likewise.
	* config/arm/arm.h (TARGET_GNU2_TLS): New.
	(OPTION_DEFAULT_SPECS): Add with-tls support.
	* config/arm/arm.md (R1_REGNUM): Define.
	(tlscall): New.
	* config/arm/arm.opt (tls_type): New enumeration type and values.
	(mtls-dialect): New switch.
	* config/arm/arm-opts.h (enum tls_type): New.

	testsuite/
	* gcc.target/arm/tlscall.c: New.

From-SVN: r175287