i386.h (ix86_tune_indices): Add X86_TUNE_INTER_UNIT_CONVERSIONS.

	* i386.h (ix86_tune_indices): Add X86_TUNE_INTER_UNIT_CONVERSIONS.
	(TARGET_INTER_UNIT_CONVERSIONS): New.
	* i386.md (floatsi expanders): Remove redundant check for SImode
	source; offload to memory when asked for.
	(floatsisf2_mixed, floatsisf2_sse, floatsidf2_mixed, floatsidf2_sse
	floatdisf2_mixed, floatsisf2_sse, floatsidf2_mixed, floatsidf2_sse):
	Update conditions;
	(floatsisf2_mixed_memory, floatsisf2_sse_memory,
	floatsidf2_mixed_memory, floatsidf2_sse_memory
	floatdisf2_mixed_memory, floatsisf2_sse_memory,
	floatsidf2_mixed_memory, floatsidf2_sse_memory): New.

From-SVN: r128369