hooks.c (hook_rtx_rtx_identity): Generic hook function that takes a single rtx and...

hooks.c (hook_rtx_rtx_identity): Generic hook function that takes a single rtx and returns it unmodified.

	* hooks.c (hook_rtx_rtx_identity): Generic hook function that
	takes a single rtx and returns it unmodified.
	* hooks.h (hook_rtx_rtx_identity): Prototype here.
	* target.h (struct gcc_target): Add "delegitimize_address"
	field to target structure.
	* target-def.h (TARGET_DELEGITIMIZE_ADDRESS):  Provide default
	for delegitimize_address target using hook_rtx_rtx_identity.
	(TARGET_INITIALIZER): Initialize delegitimize_address field
	using TARGET_DELEGITIMIZE_ADDRESS macro.
	* simplify-rtx.c (avoid_constant_pool_reference): Handle float
	extensions of constant pool references.  Use delegitimize_address
	to undo the obfuscation of "-fpic".
	* Makefile.in (simplify-rtx.o): Add dependency on target.h.

	* config/i386/i386.c (TARGET_DELEGITIMIZE_ADDRESS): Define as
	i386_simplify_dwarf_addr.
	(ix86_find_base_term): Simplify using i386_simplify_dwarf_addr.
  	(maybe_get_pool_constant): Likewise.

From-SVN: r62336