re PR target/90991 (_mm_loadu_ps instrinsic translates to vmovaps in combination...

re PR target/90991 (_mm_loadu_ps instrinsic translates to vmovaps in combination with _mm512_insertf32x4)

	PR target/90991
	* config/i386/sse.md (avx_vec_concat<mode>): Use nonimmediate_operand
	instead of register_operand for operands[1], add m to its constraints
	if operands[2] uses "C" constraint.  Ensure in condition that if
	operands[2] is not 0, then operands[1] is not a MEM.  For last two
	alternatives, use unaligned loads instead of aligned if operands[1] is
	misaligned_operand.

	* gcc.target/i386/avx2-pr90991-1.c: New test.
	* gcc.target/i386/avx512dq-pr90991-2.c: New test.

From-SVN: r272745