re PR rtl-optimization/66838 (Calling multiple SYSV AMD64 ABI functions from MS x64 ABI one results in clobbered parameters)

	PR rtl-optimization/66838
	* postreload.c (reload_cse_move2add): Also process
	CALL_INSN_FUNCTION_USAGE when resetting information of
	call-clobbered registers.

testsuite/ChangeLog:

	PR rtl-optimization/66838
	* gcc.target/i386/pr66838.c: New test.

From-SVN: r225806