Fix alpha-x-m32r-elf bugs.

Fix alpha-x-m32r-elf bugs.

	* cse.c (simplify_unary_operation): Sign-extend constants when
	they have the most significant bit set for the target.
	* real.c (endian): Sign-extend 32 bit output values on a 64 bit
	host.
	* m32r/m32r.c (m32r_expand_prologue): Store pretend_size in
	HOST_WIDE_INT temporary before negating it.
	* m32r/m32r.md (movsi_insn+1): Use ~0xffff instead of 0xffff0000.

From-SVN: r24254